diff --git a/contrib/bc/Makefile.in b/contrib/bc/Makefile.in index 3d6780d6ac95..b9136a57aa92 100644 --- a/contrib/bc/Makefile.in +++ b/contrib/bc/Makefile.in @@ -1,615 +1,643 @@ # # SPDX-License-Identifier: BSD-2-Clause # # Copyright (c) 2018-2021 Gavin D. Howard and contributors. # # Redistribution and use in source and binary forms, with or without # modification, are permitted provided that the following conditions are met: # # * Redistributions of source code must retain the above copyright notice, this # list of conditions and the following disclaimer. # # * Redistributions in binary form must reproduce the above copyright notice, # this list of conditions and the following disclaimer in the documentation # and/or other materials provided with the distribution. # # THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" # AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE # IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE # ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE # LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR # CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF # SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS # INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN # CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) # ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE # POSSIBILITY OF SUCH DAMAGE. # # %%WARNING%% # .POSIX: +ROOTDIR = %%ROOTDIR%% +INCDIR = $(ROOTDIR)/include +SRCDIR = $(ROOTDIR)/src +TESTSDIR = $(ROOTDIR)/tests +SCRIPTSDIR = $(ROOTDIR)/scripts +GENDIR = $(ROOTDIR)/gen + +BUILDDIR = %%BUILDDIR%% + SRC = %%SRC%% OBJ = %%OBJ%% GCDA = %%GCDA%% GCNO = %%GCNO%% BC_ENABLED_NAME = BC_ENABLED BC_ENABLED = %%BC_ENABLED%% DC_ENABLED_NAME = DC_ENABLED DC_ENABLED = %%DC_ENABLED%% -HEADERS = include/args.h include/file.h include/lang.h include/lex.h include/num.h include/opt.h include/parse.h include/program.h include/read.h include/status.h include/vector.h include/vm.h -BC_HEADERS = include/bc.h -DC_HEADERS = include/dc.h -HISTORY_HEADERS = include/history.h -EXTRA_MATH_HEADERS = include/rand.h -LIBRARY_HEADERS = include/bcl.h include/library.h +HEADERS = $(INCDIR)/args.h $(INCDIR)/file.h $(INCDIR)/lang.h $(INCDIR)/lex.h $(INCDIR)/num.h $(INCDIR)/opt.h $(INCDIR)/parse.h $(INCDIR)/program.h $(INCDIR)/read.h $(INCDIR)/status.h $(INCDIR)/vector.h $(INCDIR)/vm.h +BC_HEADERS = $(INCDIR)/bc.h +DC_HEADERS = $(INCDIR)/dc.h +HISTORY_HEADERS = $(INCDIR)/history.h +EXTRA_MATH_HEADERS = $(INCDIR)/rand.h +LIBRARY_HEADERS = $(INCDIR)/bcl.h $(INCDIR)/library.h GEN_DIR = gen GEN = %%GEN%% GEN_EXEC = $(GEN_DIR)/$(GEN) -GEN_C = $(GEN_DIR)/$(GEN).c +GEN_C = $(GENDIR)/$(GEN).c GEN_EMU = %%GEN_EMU%% -BC_LIB = $(GEN_DIR)/lib.bc +BC_LIB = $(GENDIR)/lib.bc BC_LIB_C = $(GEN_DIR)/lib.c BC_LIB_O = %%BC_LIB_O%% BC_LIB_GCDA = $(GEN_DIR)/lib.gcda BC_LIB_GCNO = $(GEN_DIR)/lib.gcno -BC_LIB2 = $(GEN_DIR)/lib2.bc +BC_LIB2 = $(GENDIR)/lib2.bc BC_LIB2_C = $(GEN_DIR)/lib2.c BC_LIB2_O = %%BC_LIB2_O%% BC_LIB2_GCDA = $(GEN_DIR)/lib2.gcda BC_LIB2_GCNO = $(GEN_DIR)/lib2.gcno -BC_HELP = $(GEN_DIR)/bc_help.txt +BC_HELP = $(GENDIR)/bc_help.txt BC_HELP_C = $(GEN_DIR)/bc_help.c BC_HELP_O = %%BC_HELP_O%% BC_HELP_GCDA = $(GEN_DIR)/bc_help.gcda BC_HELP_GCNO = $(GEN_DIR)/bc_help.gcno -DC_HELP = $(GEN_DIR)/dc_help.txt +DC_HELP = $(GENDIR)/dc_help.txt DC_HELP_C = $(GEN_DIR)/dc_help.c DC_HELP_O = %%DC_HELP_O%% DC_HELP_GCDA = $(GEN_DIR)/dc_help.gcda DC_HELP_GCNO = $(GEN_DIR)/dc_help.gcno BIN = bin -LOCALES = locales EXEC_SUFFIX = %%EXECSUFFIX%% EXEC_PREFIX = %%EXECPREFIX%% BC = bc DC = dc BC_EXEC = $(BIN)/$(EXEC_PREFIX)$(BC) DC_EXEC = $(BIN)/$(EXEC_PREFIX)$(DC) BC_TEST_OUTPUTS = tests/bc_outputs BC_FUZZ_OUTPUTS = tests/fuzzing/bc_outputs1 tests/fuzzing/bc_outputs2 tests/fuzzing/bc_outputs3 DC_TEST_OUTPUTS = tests/dc_outputs DC_FUZZ_OUTPUTS = tests/fuzzing/dc_outputs LIB = libbcl LIB_NAME = $(LIB).a LIBBC = $(BIN)/$(LIB_NAME) BCL = bcl BCL_TEST = $(BIN)/$(BCL) -BCL_TEST_C = tests/$(BCL).c +BCL_TEST_C = $(TESTSDIR)/$(BCL).c MANUALS = manuals BC_MANPAGE_NAME = $(EXEC_PREFIX)$(BC)$(EXEC_SUFFIX).1 BC_MANPAGE = $(MANUALS)/$(BC).1 BC_MD = $(BC_MANPAGE).md DC_MANPAGE_NAME = $(EXEC_PREFIX)$(DC)$(EXEC_SUFFIX).1 DC_MANPAGE = $(MANUALS)/$(DC).1 DC_MD = $(DC_MANPAGE).md BCL_MANPAGE_NAME = bcl.3 BCL_MANPAGE = $(MANUALS)/$(BCL_MANPAGE_NAME) BCL_MD = $(BCL_MANPAGE).md MANPAGE_INSTALL_ARGS = -Dm644 BINARY_INSTALL_ARGS = -Dm755 +PC_INSTALL_ARGS = $(MANPAGE_INSTALL_ARGS) + +BCL_PC = $(BCL).pc +PC_PATH = %%PC_PATH%% BCL_HEADER_NAME = bcl.h -BCL_HEADER = include/$(BCL_HEADER_NAME) +BCL_HEADER = $(INCDIR)/$(BCL_HEADER_NAME) %%DESTDIR%% BINDIR = %%BINDIR%% INCLUDEDIR = %%INCLUDEDIR%% LIBDIR = %%LIBDIR%% MAN1DIR = %%MAN1DIR%% MAN3DIR = %%MAN3DIR%% MAIN_EXEC = $(EXEC_PREFIX)$(%%MAIN_EXEC%%)$(EXEC_SUFFIX) EXEC = $(%%EXEC%%) NLSPATH = %%NLSPATH%% BC_BUILD_TYPE = %%BUILD_TYPE%% BC_ENABLE_LIBRARY = %%LIBRARY%% BC_ENABLE_HISTORY = %%HISTORY%% BC_ENABLE_EXTRA_MATH_NAME = BC_ENABLE_EXTRA_MATH BC_ENABLE_EXTRA_MATH = %%EXTRA_MATH%% BC_ENABLE_NLS = %%NLS%% BC_LONG_BIT = %%LONG_BIT%% BC_ENABLE_AFL = %%FUZZ%% BC_ENABLE_MEMCHECK = %%MEMCHECK%% BC_DEFAULT_BANNER = %%BC_DEFAULT_BANNER%% BC_DEFAULT_SIGINT_RESET = %%BC_DEFAULT_SIGINT_RESET%% DC_DEFAULT_SIGINT_RESET = %%DC_DEFAULT_SIGINT_RESET%% BC_DEFAULT_TTY_MODE = %%BC_DEFAULT_TTY_MODE%% DC_DEFAULT_TTY_MODE = %%DC_DEFAULT_TTY_MODE%% BC_DEFAULT_PROMPT = %%BC_DEFAULT_PROMPT%% DC_DEFAULT_PROMPT = %%DC_DEFAULT_PROMPT%% +BC_DEFAULT_EXPR_EXIT = %%BC_DEFAULT_EXPR_EXIT%% +DC_DEFAULT_EXPR_EXIT = %%DC_DEFAULT_EXPR_EXIT%% RM = rm MKDIR = mkdir SCRIPTS = ./scripts MINISTAT = ministat MINISTAT_EXEC = $(SCRIPTS)/$(MINISTAT) BITFUNCGEN = bitfuncgen BITFUNCGEN_EXEC = $(SCRIPTS)/$(BITFUNCGEN) -INSTALL = $(SCRIPTS)/exec-install.sh -SAFE_INSTALL = $(SCRIPTS)/safe-install.sh -LINK = $(SCRIPTS)/link.sh -MANPAGE = $(SCRIPTS)/manpage.sh -KARATSUBA = $(SCRIPTS)/karatsuba.py -LOCALE_INSTALL = $(SCRIPTS)/locale_install.sh -LOCALE_UNINSTALL = $(SCRIPTS)/locale_uninstall.sh +INSTALL = $(SCRIPTSDIR)/exec-install.sh +SAFE_INSTALL = $(SCRIPTSDIR)/safe-install.sh +LINK = $(SCRIPTSDIR)/link.sh +MANPAGE = $(SCRIPTSDIR)/manpage.sh +KARATSUBA = $(SCRIPTSDIR)/karatsuba.py +LOCALE_INSTALL = $(SCRIPTSDIR)/locale_install.sh +LOCALE_UNINSTALL = $(SCRIPTSDIR)/locale_uninstall.sh VALGRIND_ARGS = --error-exitcode=100 --leak-check=full --show-leak-kinds=all --errors-for-leak-kinds=all TEST_STARS = *********************************************************************** BC_NUM_KARATSUBA_LEN = %%KARATSUBA_LEN%% BC_DEFS0 = -DBC_DEFAULT_BANNER=$(BC_DEFAULT_BANNER) BC_DEFS1 = -DBC_DEFAULT_SIGINT_RESET=$(BC_DEFAULT_SIGINT_RESET) BC_DEFS2 = -DBC_DEFAULT_TTY_MODE=$(BC_DEFAULT_TTY_MODE) BC_DEFS3 = -DBC_DEFAULT_PROMPT=$(BC_DEFAULT_PROMPT) -BC_DEFS = $(BC_DEFS0) $(BC_DEFS1) $(BC_DEFS2) $(BC_DEFS3) +BC_DEFS4 = -DBC_DEFAULT_EXPR_EXIT=$(BC_DEFAULT_EXPR_EXIT) +BC_DEFS = $(BC_DEFS0) $(BC_DEFS1) $(BC_DEFS2) $(BC_DEFS3) $(BC_DEFS4) DC_DEFS1 = -DDC_DEFAULT_SIGINT_RESET=$(DC_DEFAULT_SIGINT_RESET) DC_DEFS2 = -DDC_DEFAULT_TTY_MODE=$(DC_DEFAULT_TTY_MODE) DC_DEFS3 = -DDC_DEFAULT_PROMPT=$(DC_DEFAULT_PROMPT) -DC_DEFS = $(DC_DEFS1) $(DC_DEFS2) $(DC_DEFS3) +DC_DEFS4 = -DDC_DEFAULT_EXPR_EXIT=$(DC_DEFAULT_EXPR_EXIT) +DC_DEFS = $(DC_DEFS1) $(DC_DEFS2) $(DC_DEFS3) $(DC_DEFS4) CPPFLAGS1 = -D$(BC_ENABLED_NAME)=$(BC_ENABLED) -D$(DC_ENABLED_NAME)=$(DC_ENABLED) -CPPFLAGS2 = $(CPPFLAGS1) -I./include/ -DBUILD_TYPE=$(BC_BUILD_TYPE) %%LONG_BIT_DEFINE%% +CPPFLAGS2 = $(CPPFLAGS1) -I$(INCDIR)/ -DBUILD_TYPE=$(BC_BUILD_TYPE) %%LONG_BIT_DEFINE%% CPPFLAGS3 = $(CPPFLAGS2) -DEXECPREFIX=$(EXEC_PREFIX) -DMAINEXEC=$(MAIN_EXEC) CPPFLAGS4 = $(CPPFLAGS3) -D_POSIX_C_SOURCE=200809L -D_XOPEN_SOURCE=700 %%BSD%% CPPFLAGS5 = $(CPPFLAGS4) -DBC_NUM_KARATSUBA_LEN=$(BC_NUM_KARATSUBA_LEN) CPPFLAGS6 = $(CPPFLAGS5) -DBC_ENABLE_NLS=$(BC_ENABLE_NLS) CPPFLAGS7 = $(CPPFLAGS6) -D$(BC_ENABLE_EXTRA_MATH_NAME)=$(BC_ENABLE_EXTRA_MATH) CPPFLAGS8 = $(CPPFLAGS7) -DBC_ENABLE_HISTORY=$(BC_ENABLE_HISTORY) -DBC_ENABLE_LIBRARY=$(BC_ENABLE_LIBRARY) CPPFLAGS = $(CPPFLAGS8) -DBC_ENABLE_MEMCHECK=$(BC_ENABLE_MEMCHECK) -DBC_ENABLE_AFL=$(BC_ENABLE_AFL) CFLAGS = $(CPPFLAGS) $(BC_DEFS) $(DC_DEFS) %%CPPFLAGS%% %%CFLAGS%% LDFLAGS = %%LDFLAGS%% HOSTCFLAGS = %%HOSTCFLAGS%% CC = %%CC%% HOSTCC = %%HOSTCC%% BC_LIB_C_ARGS = bc_lib bc_lib_name $(BC_ENABLED_NAME) 1 BC_LIB2_C_ARGS = bc_lib2 bc_lib2_name "$(BC_ENABLED_NAME) && $(BC_ENABLE_EXTRA_MATH_NAME)" 1 OBJS = $(DC_HELP_O) $(BC_HELP_O) $(BC_LIB_O) $(BC_LIB2_O) $(OBJ) all: %%DEFAULT_TARGET%% %%DEFAULT_TARGET%%: %%DEFAULT_TARGET_PREREQS%% %%DEFAULT_TARGET_CMD%% %%SECOND_TARGET%%: %%SECOND_TARGET_PREREQS%% %%SECOND_TARGET_CMD%% -$(GEN_EXEC): +$(GEN_DIR): + mkdir -p $(GEN_DIR) + +$(GEN_EXEC): $(GEN_DIR) %%GEN_EXEC_TARGET%% $(BC_LIB_C): $(GEN_EXEC) $(BC_LIB) $(GEN_EMU) $(GEN_EXEC) $(BC_LIB) $(BC_LIB_C) $(BC_LIB_C_ARGS) $(BC_LIB_O): $(BC_LIB_C) $(CC) $(CFLAGS) -o $@ -c $< $(BC_LIB2_C): $(GEN_EXEC) $(BC_LIB2) $(GEN_EMU) $(GEN_EXEC) $(BC_LIB2) $(BC_LIB2_C) $(BC_LIB2_C_ARGS) $(BC_LIB2_O): $(BC_LIB2_C) $(CC) $(CFLAGS) -o $@ -c $< $(BC_HELP_C): $(GEN_EXEC) $(BC_HELP) $(GEN_EMU) $(GEN_EXEC) $(BC_HELP) $(BC_HELP_C) bc_help "" $(BC_ENABLED_NAME) $(BC_HELP_O): $(BC_HELP_C) $(CC) $(CFLAGS) -o $@ -c $< $(DC_HELP_C): $(GEN_EXEC) $(DC_HELP) $(GEN_EMU) $(GEN_EXEC) $(DC_HELP) $(DC_HELP_C) dc_help "" $(DC_ENABLED_NAME) $(DC_HELP_O): $(DC_HELP_C) $(CC) $(CFLAGS) -o $@ -c $< $(BIN): $(MKDIR) -p $(BIN) +src: + $(MKDIR) -p src + headers: %%HEADERS%% $(MINISTAT): - $(HOSTCC) $(HOSTCFLAGS) -lm -o $(MINISTAT_EXEC) scripts/ministat.c + mkdir -p $(SCRIPTS) + $(HOSTCC) $(HOSTCFLAGS) -lm -o $(MINISTAT_EXEC) $(ROOTDIR)/scripts/ministat.c $(BITFUNCGEN): - $(HOSTCC) $(HOSTCFLAGS) -lm -o $(BITFUNCGEN_EXEC) scripts/bitfuncgen.c + mkdir -p $(SCRIPTS) + $(HOSTCC) $(HOSTCFLAGS) -lm -o $(BITFUNCGEN_EXEC) $(ROOTDIR)/scripts/bitfuncgen.c help: @printf 'available targets:\n' @printf '\n' @printf ' all (default) builds %%EXECUTABLES%%\n' @printf ' check alias for `make test`\n' @printf ' clean removes all build files\n' @printf ' clean_config removes all build files as well as the generated Makefile\n' @printf ' clean_tests removes all build files, the generated Makefile,\n' @printf ' and generated tests\n' @printf ' install installs binaries to "%s%s"\n' "$(DESTDIR)" "$(BINDIR)" @printf ' and (if enabled) manpages to "%s%s"\n' "$(DESTDIR)" "$(MAN1DIR)" @printf ' karatsuba runs the karatsuba script (requires Python 3)\n' @printf ' karatsuba_test runs the karatsuba script while running tests\n' @printf ' (requires Python 3)\n' @printf ' uninstall uninstalls binaries from "%s%s"\n' "$(DESTDIR)" "$(BINDIR)" @printf ' and (if enabled) manpages from "%s%s"\n' "$(DESTDIR)" "$(MAN1DIR)" @printf ' test runs the test suite\n' @printf ' test_bc runs the bc test suite, if bc has been built\n' @printf ' test_dc runs the dc test suite, if dc has been built\n' @printf ' time_test runs the test suite, displaying times for some things\n' @printf ' time_test_bc runs the bc test suite, displaying times for some things\n' @printf ' time_test_dc runs the dc test suite, displaying times for some things\n' @printf ' timeconst runs the test on the Linux timeconst.bc script,\n' @printf ' if it exists and bc has been built\n' @printf ' valgrind runs the test suite through valgrind\n' @printf ' valgrind_bc runs the bc test suite, if bc has been built,\n' @printf ' through valgrind\n' @printf ' valgrind_dc runs the dc test suite, if dc has been built,\n' @printf ' through valgrind\n' run_all_tests: bc_all_tests timeconst_all_tests dc_all_tests run_all_tests_np: bc_all_tests_np timeconst_all_tests dc_all_tests_np bc_all_tests: %%BC_ALL_TESTS%% bc_all_tests_np: %%BC_ALL_TESTS_NP%% timeconst_all_tests: %%TIMECONST_ALL_TESTS%% dc_all_tests: %%DC_ALL_TESTS%% dc_all_tests_np: %%DC_ALL_TESTS_NP%% history_all_tests: %%HISTORY_TESTS%% check: test test: %%TESTS%% test_bc: test_bc_header test_bc_tests test_bc_scripts test_bc_errors test_bc_stdin test_bc_read test_bc_other @printf '\nAll bc tests passed.\n\n$(TEST_STARS)\n' test_bc_tests:%%BC_TESTS%% test_bc_scripts:%%BC_SCRIPT_TESTS%% test_bc_stdin: - @sh tests/stdin.sh bc %%BC_TEST_EXEC%% + @export BC_TEST_OUTPUT_DIR="$(BUILDDIR)/tests"; sh $(TESTSDIR)/stdin.sh bc %%BC_TEST_EXEC%% test_bc_read: - @sh tests/read.sh bc %%BC_TEST_EXEC%% + @export BC_TEST_OUTPUT_DIR="$(BUILDDIR)/tests"; sh $(TESTSDIR)/read.sh bc %%BC_TEST_EXEC%% test_bc_errors: test_bc_error_lines%%BC_ERROR_TESTS%% test_bc_error_lines: - @sh tests/errors.sh bc %%BC_TEST_EXEC%% + @export BC_TEST_OUTPUT_DIR="$(BUILDDIR)/tests"; sh $(TESTSDIR)/errors.sh bc %%BC_TEST_EXEC%% test_bc_other: - @sh tests/other.sh bc $(BC_ENABLE_EXTRA_MATH) %%BC_TEST_EXEC%% + @export BC_TEST_OUTPUT_DIR="$(BUILDDIR)/tests"; sh $(TESTSDIR)/other.sh bc $(BC_ENABLE_EXTRA_MATH) %%BC_TEST_EXEC%% test_bc_header: @printf '$(TEST_STARS)\n\nRunning bc tests...\n\n' test_dc: test_dc_header test_dc_tests test_dc_scripts test_dc_errors test_dc_stdin test_dc_read test_dc_other @printf '\nAll dc tests passed.\n\n$(TEST_STARS)\n' test_dc_tests:%%DC_TESTS%% test_dc_scripts:%%DC_SCRIPT_TESTS%% test_dc_stdin: - @sh tests/stdin.sh dc %%DC_TEST_EXEC%% + @export BC_TEST_OUTPUT_DIR="$(BUILDDIR)/tests"; sh $(TESTSDIR)/stdin.sh dc %%DC_TEST_EXEC%% test_dc_read: - @sh tests/read.sh dc %%DC_TEST_EXEC%% + @export BC_TEST_OUTPUT_DIR="$(BUILDDIR)/tests"; sh $(TESTSDIR)/read.sh dc %%DC_TEST_EXEC%% test_dc_errors: test_dc_error_lines%%DC_ERROR_TESTS%% test_dc_error_lines: - @sh tests/errors.sh dc %%DC_TEST_EXEC%% + @export BC_TEST_OUTPUT_DIR="$(BUILDDIR)/tests"; sh $(TESTSDIR)/errors.sh dc %%DC_TEST_EXEC%% test_dc_other: - @sh tests/other.sh dc $(BC_ENABLE_EXTRA_MATH) %%DC_TEST_EXEC%% + @export BC_TEST_OUTPUT_DIR="$(BUILDDIR)/tests"; sh $(TESTSDIR)/other.sh dc $(BC_ENABLE_EXTRA_MATH) %%DC_TEST_EXEC%% test_dc_header: @printf '$(TEST_STARS)\n\nRunning dc tests...\n\n' timeconst: %%TIMECONST%% test_history: test_history_header test_bc_history test_dc_history @printf '\nAll history tests passed.\n\n$(TEST_STARS)\n' test_bc_history:%%BC_HISTORY_TEST_PREREQS%% test_bc_history_all: test_bc_history0 test_bc_history1 test_bc_history2 test_bc_history3 test_bc_history4 test_bc_history5 test_bc_history6 test_bc_history7 test_bc_history8 test_bc_history9 test_bc_history10 test_bc_history11 test_bc_history12 test_bc_history13 test_bc_history14 test_bc_history15 test_bc_history16 test_bc_history17 test_bc_history18 test_bc_history19 test_bc_history20 test_bc_history21 test_bc_history_skip: @printf 'No bc history tests to run\n' test_bc_history0: - @sh tests/history.sh bc 0 %%BC_TEST_EXEC%% + @sh $(TESTSDIR)/history.sh bc 0 %%BC_TEST_EXEC%% test_bc_history1: - @sh tests/history.sh bc 1 %%BC_TEST_EXEC%% + @sh $(TESTSDIR)/history.sh bc 1 %%BC_TEST_EXEC%% test_bc_history2: - @sh tests/history.sh bc 2 %%BC_TEST_EXEC%% + @sh $(TESTSDIR)/history.sh bc 2 %%BC_TEST_EXEC%% test_bc_history3: - @sh tests/history.sh bc 3 %%BC_TEST_EXEC%% + @sh $(TESTSDIR)/history.sh bc 3 %%BC_TEST_EXEC%% test_bc_history4: - @sh tests/history.sh bc 4 %%BC_TEST_EXEC%% + @sh $(TESTSDIR)/history.sh bc 4 %%BC_TEST_EXEC%% test_bc_history5: - @sh tests/history.sh bc 5 %%BC_TEST_EXEC%% + @sh $(TESTSDIR)/history.sh bc 5 %%BC_TEST_EXEC%% test_bc_history6: - @sh tests/history.sh bc 6 %%BC_TEST_EXEC%% + @sh $(TESTSDIR)/history.sh bc 6 %%BC_TEST_EXEC%% test_bc_history7: - @sh tests/history.sh bc 7 %%BC_TEST_EXEC%% + @sh $(TESTSDIR)/history.sh bc 7 %%BC_TEST_EXEC%% test_bc_history8: - @sh tests/history.sh bc 8 %%BC_TEST_EXEC%% + @sh $(TESTSDIR)/history.sh bc 8 %%BC_TEST_EXEC%% test_bc_history9: - @sh tests/history.sh bc 9 %%BC_TEST_EXEC%% + @sh $(TESTSDIR)/history.sh bc 9 %%BC_TEST_EXEC%% test_bc_history10: - @sh tests/history.sh bc 10 %%BC_TEST_EXEC%% + @sh $(TESTSDIR)/history.sh bc 10 %%BC_TEST_EXEC%% test_bc_history11: - @sh tests/history.sh bc 11 %%BC_TEST_EXEC%% + @sh $(TESTSDIR)/history.sh bc 11 %%BC_TEST_EXEC%% test_bc_history12: - @sh tests/history.sh bc 12 %%BC_TEST_EXEC%% + @sh $(TESTSDIR)/history.sh bc 12 %%BC_TEST_EXEC%% test_bc_history13: - @sh tests/history.sh bc 13 %%BC_TEST_EXEC%% + @sh $(TESTSDIR)/history.sh bc 13 %%BC_TEST_EXEC%% test_bc_history14: - @sh tests/history.sh bc 14 %%BC_TEST_EXEC%% + @sh $(TESTSDIR)/history.sh bc 14 %%BC_TEST_EXEC%% test_bc_history15: - @sh tests/history.sh bc 15 %%BC_TEST_EXEC%% + @sh $(TESTSDIR)/history.sh bc 15 %%BC_TEST_EXEC%% test_bc_history16: - @sh tests/history.sh bc 16 %%BC_TEST_EXEC%% + @sh $(TESTSDIR)/history.sh bc 16 %%BC_TEST_EXEC%% test_bc_history17: - @sh tests/history.sh bc 17 %%BC_TEST_EXEC%% + @sh $(TESTSDIR)/history.sh bc 17 %%BC_TEST_EXEC%% test_bc_history18: - @sh tests/history.sh bc 18 %%BC_TEST_EXEC%% + @sh $(TESTSDIR)/history.sh bc 18 %%BC_TEST_EXEC%% test_bc_history19: - @sh tests/history.sh bc 19 %%BC_TEST_EXEC%% + @sh $(TESTSDIR)/history.sh bc 19 %%BC_TEST_EXEC%% test_bc_history20: - @sh tests/history.sh bc 20 %%BC_TEST_EXEC%% + @sh $(TESTSDIR)/history.sh bc 20 %%BC_TEST_EXEC%% test_bc_history21: - @sh tests/history.sh bc 21 %%BC_TEST_EXEC%% + @sh $(TESTSDIR)/history.sh bc 21 %%BC_TEST_EXEC%% test_dc_history:%%DC_HISTORY_TEST_PREREQS%% -test_dc_history_all: test_dc_history0 test_dc_history1 test_dc_history2 test_dc_history3 test_dc_history4 test_dc_history5 test_dc_history6 test_dc_history7 test_dc_history8 test_dc_history9 +test_dc_history_all: test_dc_history0 test_dc_history1 test_dc_history2 test_dc_history3 test_dc_history4 test_dc_history5 test_dc_history6 test_dc_history7 test_dc_history8 test_dc_history9 test_dc_history10 test_dc_history_skip: @printf 'No dc history tests to run\n' test_dc_history0: - @sh tests/history.sh dc 0 %%DC_TEST_EXEC%% + @sh $(TESTSDIR)/history.sh dc 0 %%DC_TEST_EXEC%% test_dc_history1: - @sh tests/history.sh dc 1 %%DC_TEST_EXEC%% + @sh $(TESTSDIR)/history.sh dc 1 %%DC_TEST_EXEC%% test_dc_history2: - @sh tests/history.sh dc 2 %%DC_TEST_EXEC%% + @sh $(TESTSDIR)/history.sh dc 2 %%DC_TEST_EXEC%% test_dc_history3: - @sh tests/history.sh dc 3 %%DC_TEST_EXEC%% + @sh $(TESTSDIR)/history.sh dc 3 %%DC_TEST_EXEC%% test_dc_history4: - @sh tests/history.sh dc 4 %%DC_TEST_EXEC%% + @sh $(TESTSDIR)/history.sh dc 4 %%DC_TEST_EXEC%% test_dc_history5: - @sh tests/history.sh dc 5 %%DC_TEST_EXEC%% + @sh $(TESTSDIR)/history.sh dc 5 %%DC_TEST_EXEC%% test_dc_history6: - @sh tests/history.sh dc 6 %%DC_TEST_EXEC%% + @sh $(TESTSDIR)/history.sh dc 6 %%DC_TEST_EXEC%% test_dc_history7: - @sh tests/history.sh dc 7 %%DC_TEST_EXEC%% + @sh $(TESTSDIR)/history.sh dc 7 %%DC_TEST_EXEC%% test_dc_history8: - @sh tests/history.sh dc 8 %%DC_TEST_EXEC%% + @sh $(TESTSDIR)/history.sh dc 8 %%DC_TEST_EXEC%% test_dc_history9: - @sh tests/history.sh dc 9 %%DC_TEST_EXEC%% + @sh $(TESTSDIR)/history.sh dc 9 %%DC_TEST_EXEC%% + +test_dc_history10: + @sh $(TESTSDIR)/history.sh dc 10 %%DC_TEST_EXEC%% test_history_header: @printf '$(TEST_STARS)\n\nRunning history tests...\n\n' library_test: $(LIBBC) $(CC) $(CFLAGS) $(BCL_TEST_C) $(LIBBC) -o $(BCL_TEST) test_library: library_test $(BCL_TEST) karatsuba: %%KARATSUBA%% karatsuba_test: %%KARATSUBA_TEST%% coverage_output: %%COVERAGE_OUTPUT%% coverage:%%COVERAGE_PREREQS%% manpages: $(MANPAGE) bc $(MANPAGE) dc $(MANPAGE) bcl clean_gen: @$(RM) -f $(GEN_EXEC) clean:%%CLEAN_PREREQS%% @printf 'Cleaning files...\n' @$(RM) -f src/*.tmp gen/*.tmp @$(RM) -f $(OBJ) @$(RM) -f $(BC_EXEC) @$(RM) -f $(DC_EXEC) @$(RM) -fr $(BIN) - @$(RM) -f $(LOCALES)/*.cat @$(RM) -f $(BC_LIB_C) $(BC_LIB_O) @$(RM) -f $(BC_LIB2_C) $(BC_LIB2_O) @$(RM) -f $(BC_HELP_C) $(BC_HELP_O) @$(RM) -f $(DC_HELP_C) $(DC_HELP_O) - @$(RM) -fr Debug/ Release/ + @$(RM) -fr vs/bin/ vs/lib/ clean_benchmarks: @printf 'Cleaning benchmarks...\n' @$(RM) -f $(MINISTAT_EXEC) - @$(RM) -f benchmarks/bc/*.txt - @$(RM) -f benchmarks/dc/*.txt + @$(RM) -f $(ROOTDIR)/benchmarks/bc/*.txt + @$(RM) -f $(ROOTDIR)/benchmarks/dc/*.txt clean_config: clean clean_benchmarks @printf 'Cleaning config...\n' @$(RM) -f Makefile @$(RM) -f $(BC_MD) $(BC_MANPAGE) @$(RM) -f $(DC_MD) $(DC_MANPAGE) clean_coverage: @printf 'Cleaning coverage files...\n' @$(RM) -f *.gcov @$(RM) -f *.html @$(RM) -f *.gcda *.gcno @$(RM) -f *.profraw @$(RM) -f $(GCDA) $(GCNO) @$(RM) -f $(BC_GCDA) $(BC_GCNO) @$(RM) -f $(DC_GCDA) $(DC_GCNO) @$(RM) -f $(HISTORY_GCDA) $(HISTORY_GCNO) @$(RM) -f $(RAND_GCDA) $(RAND_GCNO) @$(RM) -f $(BC_LIB_GCDA) $(BC_LIB_GCNO) @$(RM) -f $(BC_LIB2_GCDA) $(BC_LIB2_GCNO) @$(RM) -f $(BC_HELP_GCDA) $(BC_HELP_GCNO) @$(RM) -f $(DC_HELP_GCDA) $(DC_HELP_GCNO) clean_tests: clean clean_config clean_coverage @printf 'Cleaning test files...\n' @$(RM) -fr $(BC_TEST_OUTPUTS) $(DC_TEST_OUTPUTS) @$(RM) -fr $(BC_FUZZ_OUTPUTS) $(DC_FUZZ_OUTPUTS) - @$(RM) -f tests/bc/parse.txt tests/bc/parse_results.txt - @$(RM) -f tests/bc/print.txt tests/bc/print_results.txt - @$(RM) -f tests/bc/bessel.txt tests/bc/bessel_results.txt - @$(RM) -f tests/bc/strings2.txt tests/bc/strings2_results.txt - @$(RM) -f tests/bc/scripts/bessel.txt - @$(RM) -f tests/bc/scripts/parse.txt - @$(RM) -f tests/bc/scripts/print.txt - @$(RM) -f tests/bc/scripts/add.txt - @$(RM) -f tests/bc/scripts/divide.txt - @$(RM) -f tests/bc/scripts/multiply.txt - @$(RM) -f tests/bc/scripts/subtract.txt - @$(RM) -f tests/bc/scripts/strings2.txt - @$(RM) -f tests/dc/scripts/prime.txt + @$(RM) -f $(TESTSDIR)/bc/parse.txt $(TESTSDIR)/bc/parse_results.txt + @$(RM) -f $(TESTSDIR)/bc/print.txt $(TESTSDIR)/bc/print_results.txt + @$(RM) -f $(TESTSDIR)/bc/bessel.txt $(TESTSDIR)/bc/bessel_results.txt + @$(RM) -f $(TESTSDIR)/bc/strings2.txt $(TESTSDIR)/bc/strings2_results.txt + @$(RM) -f $(TESTSDIR)/bc/scripts/bessel.txt + @$(RM) -f $(TESTSDIR)/bc/scripts/parse.txt + @$(RM) -f $(TESTSDIR)/bc/scripts/print.txt + @$(RM) -f $(TESTSDIR)/bc/scripts/add.txt + @$(RM) -f $(TESTSDIR)/bc/scripts/divide.txt + @$(RM) -f $(TESTSDIR)/bc/scripts/multiply.txt + @$(RM) -f $(TESTSDIR)/bc/scripts/subtract.txt + @$(RM) -f $(TESTSDIR)/bc/scripts/strings2.txt + @$(RM) -f $(TESTSDIR)/dc/scripts/prime.txt @$(RM) -f .log_*.txt @$(RM) -f .math.txt .results.txt .ops.txt @$(RM) -f .test.txt @$(RM) -f tags .gdbbreakpoints .gdb_history .gdbsetup @$(RM) -f cscope.* @$(RM) -f bc.old @$(RM) -f $(BITFUNCGEN_EXEC) install_locales: %%INSTALL_LOCALES%% install_bc_manpage: $(SAFE_INSTALL) $(MANPAGE_INSTALL_ARGS) $(BC_MANPAGE) $(DESTDIR)$(MAN1DIR)/$(BC_MANPAGE_NAME) install_dc_manpage: $(SAFE_INSTALL) $(MANPAGE_INSTALL_ARGS) $(DC_MANPAGE) $(DESTDIR)$(MAN1DIR)/$(DC_MANPAGE_NAME) install_bcl_manpage: $(SAFE_INSTALL) $(MANPAGE_INSTALL_ARGS) $(BCL_MANPAGE) $(DESTDIR)$(MAN3DIR)/$(BCL_MANPAGE_NAME) install_bcl_header: $(SAFE_INSTALL) $(MANPAGE_INSTALL_ARGS) $(BCL_HEADER) $(DESTDIR)$(INCLUDEDIR)/$(BCL_HEADER_NAME) install_execs: - $(INSTALL) $(DESTDIR)$(BINDIR) "$(EXEC_SUFFIX)" + $(INSTALL) $(DESTDIR)$(BINDIR) "$(EXEC_SUFFIX)" "$(BUILDDIR)/bin" -install_library: +install_library: install_bcl_header $(SAFE_INSTALL) $(BINARY_INSTALL_ARGS) $(LIBBC) $(DESTDIR)$(LIBDIR)/$(LIB_NAME) + %%PKG_CONFIG_INSTALL%% install:%%INSTALL_LOCALES_PREREQS%%%%INSTALL_MAN_PREREQS%%%%INSTALL_PREREQS%% uninstall_locales: $(LOCALE_UNINSTALL) $(NLSPATH) $(MAIN_EXEC) $(DESTDIR) uninstall_bc_manpage: $(RM) -f $(DESTDIR)$(MAN1DIR)/$(BC_MANPAGE_NAME) uninstall_bc: $(RM) -f $(DESTDIR)$(BINDIR)/$(EXEC_PREFIX)$(BC)$(EXEC_SUFFIX) uninstall_dc_manpage: $(RM) -f $(DESTDIR)$(MAN1DIR)/$(DC_MANPAGE_NAME) uninstall_dc: $(RM) -f $(DESTDIR)$(BINDIR)/$(EXEC_PREFIX)$(DC)$(EXEC_SUFFIX) -uninstall_library: +uninstall_library: uninstall_bcl_header $(RM) -f $(DESTDIR)$(LIBDIR)/$(LIB_NAME) + %%PKG_CONFIG_UNINSTALL%% uninstall_bcl_header: $(RM) -f $(DESTDIR)$(INCLUDEDIR)/$(BCL_HEADER_NAME) uninstall_bcl_manpage: $(RM) -f $(DESTDIR)$(MAN3DIR)/$(BCL_MANPAGE_NAME) uninstall:%%UNINSTALL_LOCALES_PREREQS%%%%UNINSTALL_MAN_PREREQS%%%%UNINSTALL_PREREQS%% diff --git a/contrib/bc/NEWS.md b/contrib/bc/NEWS.md index 5251096d9f2a..5d0126b821a8 100644 --- a/contrib/bc/NEWS.md +++ b/contrib/bc/NEWS.md @@ -1,1211 +1,1231 @@ # News +## 5.2.1 + +This is a production release that fixes two parse bugs when in POSIX standard +mode. One of these bugs was due to a quirk of the POSIX grammar, and the other +was because `bc` was too strict. + +## 5.2.0 + +This is a production release that adds a new feature, fixes some bugs, and adds +out-of-source builds and a `pkg-config` file for `bcl`. + +The new feature is the ability to turn off exiting on expressions. It is also +possible to set the default using `configure.sh`. This behavior used to exist +with the `BC_EXPR_EXIT` environment variable, which is now used again. + +Bugs fixed include: + +* Some possible race conditions with error handling. +* Install and uninstall targets for `bcl` did not work. + ## 5.1.1 This is a production release that completes a bug fix from `5.1.0`. The bug exists in all versions of `bc`. The bug was that `if` statements without `else` statements would not be handled correctly at the end of files or right before a function definition. ## 5.1.0 This is a production release with some fixes and new features. * Fixed a bug where an `if` statement without an `else` before defining a function caused an error. * Fixed a bug with the `bc` banner and `-q`. * Fixed a bug on Windows where files were not read correctly. * Added a command-line flag (`-z`) to make `bc` and `dc` print leading zeroes on numbers `-1 < x < 1`. * Added four functions to `lib2.bc` (`plz()`, `plznl()`, `pnlz()`, and `pnlznl()`) to allow printing numbers with or without leading zeros, despite the use of `-z` or not. * Added builtin functions to query global state like line length, global stacks, and leading zeroes. * Added a command-line flag (`-L`) to disable wrapping when printing numbers. * Improved builds on Windows. ## 5.0.2 This is a production release with one fix for a flaky test. If you have not experienced problems with the test suite, you do ***NOT*** need to upgrade. The test was one that tested whether `bc` fails gracefully when it can't allocate memory. Unfortunately, there are cases when Linux and FreeBSD lie and pretend to allocate the memory. The reason they do this is because a lot of programs don't use all of the memory they allocate, so those OS's usually get away with it. However, this `bc` uses all of the memory it allocates (at least at page granularity), so when it tries to use the memory, FreeBSD and Linux kill it. This only happens sometimes, however. Other times (on my machine), they do, in fact, refuse the request. So I changed the test to not test for that because I think the graceful failure code won't really change much. ## 5.0.1 This is a production release with two fixes: * Fix for the build on Mac OSX. * Fix for the build on Android. Users that do not use those platforms do ***NOT*** need to update. ## 5.0.0 This is a major production release with several changes: * Added support for OpenBSD's `pledge()` and `unveil()`. * Fixed print bug where a backslash newline combo was printed even if only one digit was left, something I blindly copied from GNU `bc`, like a fool. * Fixed bugs in the manuals. * Fixed a possible multiplication overflow in power. * Temporary numbers are garbage collected if allocation fails, and the allocation is retried. This is to make `bc` and `dc` more resilient to running out of memory. * Limited the number of temporary numbers and made the space for them static so that allocating more space for them cannot fail. * Allowed integers with non-zero `scale` to be used with power, places, and shift operators. * Added greatest common divisor and least common multiple to `lib2.bc`. * Added `SIGQUIT` handling to history. * Added a command to `dc` (`y`) to get the length of register stacks. * Fixed multi-digit bugs in `lib2.bc`. * Removed the no prompt build option. * Created settings that builders can set defaults for and users can set their preferences for. This includes the `bc` banner, resetting on `SIGINT`, TTY mode, and prompt. * Added history support to Windows. * Fixed bugs with the handling of register names in `dc`. * Fixed bugs with multi-line comments and strings in both calculators. * Added a new error type and message for `dc` when register stacks don't have enough items. * Optimized string allocation. * Made `bc` and `dc` UTF-8 capable. * Fixed a bug with `void` functions. * Fixed a misspelled symbol in `bcl`. This is technically a breaking change, which requires this to be `5.0.0`. * Added the ability for users to get the copyright banner back. * Added the ability for users to have `bc` and `dc` quit on `SIGINT`. * Added the ability for users to disable prompt and TTY mode by environment variables. * Added the ability for users to redefine keywords. This is another reason this is `5.0.0`. * Added `dc`'s modular exponentiation and divmod to `bc`. * Added the ability to assign strings to variables and array elements and pass them to functions in `bc`. * Added `dc`'s asciify command and stream printing to `bc`. * Added a command to `dc` (`Y`) to get the length of an array. * Added a command to `dc` (`,`) to get the depth of the execution stack. * Added bitwise and, or, xor, left shift, right shift, reverse, left rotate, right rotate, and mod functions to `lib2.bc`. * Added the functions `s2u(x)` and `s2un(x,n)`, to `lib2.bc`. ## 4.0.2 This is a production release that fixes two bugs: 1. If no files are used and the first statement on `stdin` is invalid, `scale` would not be set to `20` even if `-l` was used. 2. When using history, `bc` failed to respond properly to `SIGSTOP` and `SIGTSTP`. ## 4.0.1 This is a production release that only adds one thing: flushing output when it is printed with a print statement. ## 4.0.0 This is a production release with many fixes, a new command-line option, and a big surprise: * A bug was fixed in `dc`'s `P` command where the item on the stack was *not* popped. * Various bugs in the manuals have been fixed. * A known bug was fixed where history did not interact well with prompts printed by user code without newlines. * A new command-line option, `-R` and `--no-read-prompt` was added to disable just the prompt when using `read()` (`bc`) or `?` (`dc`). * And finally, **official support for Windows was added**. The last item is why this is a major version bump. Currently, only one set of build options (extra math and prompt enabled, history and NLS/locale support disabled, both calculators enabled) is supported on Windows. However, both debug and release builds are supported. In addition, Windows builds are supported for the the library (`bcl`). For more details about how to build on Windows, see the [README][5] or the [build manual][13]. ## 3.3.4 This is a production release that fixes a small bug. The bug was that output was not flushed before a `read()` call, so prompts without a newline on the end were not flushed before the `read()` call. This is such a tiny bug that users only need to upgrade if they are affected. ## 3.3.3 This is a production release with one tweak and fixes for manuals. The tweak is that `length(0)` returns `1` instead of `0`. In `3.3.1`, I changed it so `length(0.x)`, where `x` could be any number of digits, returned the `scale`, but `length(0)` still returned `0` because I believe that `0` has `0` significant digits. After request of FreeBSD and considering the arguments of a mathematician, compatibility with other `bc`'s, and the expectations of users, I decided to make the change. The fixes for manuals fixed a bug where `--` was rendered as `-`. ## 3.3.2 This is a production release that fixes a divide-by-zero bug in `root()` in the [extended math library][16]. All previous versions with `root()` have the bug. ## 3.3.1 This is a production release that fixes a bug. The bug was in the reporting of number length when the value was 0. ## 3.3.0 This is a production release that changes one behavior and fixes documentation bugs. The changed behavior is the treatment of `-e` and `-f` when given through `BC_ENV_ARGS` or `DC_ENV_ARGS`. Now `bc` and `dc` do not exit when those options (or their equivalents) are given through those environment variables. However, `bc` and `dc` still exit when they or their equivalents are given on the command-line. ## 3.2.7 This is a production release that removes a small non-portable shell operation in `configure.sh`. This problem was only noticed on OpenBSD, not FreeBSD or Linux. Non-OpenBSD users do ***NOT*** need to upgrade, although NetBSD users may also need to upgrade. ## 3.2.6 This is a production release that fixes the build on FreeBSD. There was a syntax error in `configure.sh` that the Linux shell did not catch, and FreeBSD depends on the existence of `tests/all.sh`. All users that already upgraded to `3.2.5` should update to this release, with my apologies for the poor release of `3.2.5`. Other users should skip `3.2.5` in favor of this version. ## 3.2.5 This is a production release that fixes several bugs and adds a couple small things. The two most important bugs were bugs that causes `dc` to access memory out-of-bounds (crash in debug builds). This was found by upgrading to `afl++` from `afl`. Both were caused by a failure to distinguish between the same two cases. Another bug was the failure to put all of the licenses in the `LICENSE.md` file. Third, some warnings by `scan-build` were found and eliminated. This needed one big change: `bc` and `dc` now bail out as fast as possible on fatal errors instead of unwinding the stack. Fourth, the pseudo-random number now attempts to seed itself with `/dev/random` if `/dev/urandom` fails. Finally, this release has a few quality-of-life changes to the build system. The usage should not change at all; the only thing that changed was making sure the `Makefile.in` was written to rebuild properly when headers changed and to not rebuild when not necessary. ## 3.2.4 This is a production release that fixes a warning on `gcc` 6 or older, which does not have an attribute that is used. Users do ***NOT*** need to upgrade if they don't use `gcc` 6 or older. ## 3.2.3 This is a production release that fixes a bug in `gen/strgen.sh`. I recently changed `gen/strgen.c`, but I did not change `gen/strgen.sh`. Users that do not use `gen/strgen.sh` do not need to upgrade. ## 3.2.2 This is a production release that fixes a portability bug in `configure.sh`. The bug was using the GNU `find` extension `-wholename`. ## 3.2.1 This is a production release that has one fix for `bcl(3)`. It is technically not a bug fix since the behavior is undefined, but the `BclNumber`s that `bcl_divmod()` returns will be set to `BCL_ERROR_INVALID_NUM` if there is an error. Previously, they were not set. ## 3.2.0 This is a production release that has one bug fix and a major addition. The bug fix was a missing `auto` variable in the bessel `j()` function in the math library. The major addition is a way to build a version of `bc`'s math code as a library. This is done with the `-a` option to `configure.sh`. The API for the library can be read in `./manuals/bcl.3.md` or `man bcl` once the library is installed with `make install`. This library was requested by developers before I even finished version 1.0, but I could not figure out how to do it until now. If the library has API breaking changes, the major version of `bc` will be incremented. ## 3.1.6 This is a production release that fixes a new warning from Clang 12 for FreeBSD and also removes some possible undefined behavior found by UBSan that compilers did not seem to take advantage of. Users do ***NOT*** need to upgrade, if they do not want to. ## 3.1.5 This is a production release that fixes the Chinese locales (which caused `bc` to crash) and a crash caused by `bc` executing code when it should not have been able to. ***ALL USERS SHOULD UPGRADE.*** ## 3.1.4 This is a production release that fixes one bug, changes two behaviors, and removes one environment variable. The bug is like the one in the last release except it applies if files are being executed. I also made the fix more general. The behavior that was changed is that `bc` now exits when given `-e`, `-f`, `--expression` or `--file`. However, if the last one of those is `-f-` (using `stdin` as the file), `bc` does not exit. If `-f-` exists and is not the last of the `-e` and `-f` options (and equivalents), `bc` gives a fatal error and exits. Next, I removed the `BC_EXPR_EXIT` and `DC_EXPR_EXIT` environment variables since their use is not needed with the behavior change. Finally, I made it so `bc` does not print the header, though the `-q` and `--quiet` options were kept for compatibility with GNU `bc`. ## 3.1.3 This is a production release that fixes one minor bug: if `bc` was invoked like the following, it would error: ``` echo "if (1 < 3) 1" | bc ``` Unless users run into this bug, they do not need to upgrade, but it is suggested that they do. ## 3.1.2 This is a production release that adds a way to install *all* locales. Users do ***NOT*** need to upgrade. For package maintainers wishing to make use of the change, just pass `-l` to `configure.sh`. ## 3.1.1 This is a production release that adds two Spanish locales. Users do ***NOT*** need to upgrade, unless they want those locales. ## 3.1.0 This is a production release that adjusts one behavior, fixes eight bugs, and improves manpages for FreeBSD. Because this release fixes bugs, **users and package maintainers should update to this version as soon as possible**. The behavior that was adjusted was how code from the `-e` and `-f` arguments (and equivalents) were executed. They used to be executed as one big chunk, but in this release, they are now executed line-by-line. The first bug fix in how output to `stdout` was handled in `SIGINT`. If a `SIGINT` came in, the `stdout` buffer was not correctly flushed. In fact, a clean-up function was not getting called. This release fixes that bug. The second bug is in how `dc` handled input from `stdin`. This affected `bc` as well since it was a mishandling of the `stdin` buffer. The third fixed bug was that `bc` and `dc` could `abort()` (in debug mode) when receiving a `SIGTERM`. This one was a race condition with pushing and popping items onto and out of vectors. The fourth bug fixed was that `bc` could leave extra items on the stack and thus, not properly clean up some memory. (The memory would still get `free()`'ed, but it would not be `free()`'ed when it could have been.) The next two bugs were bugs in `bc`'s parser that caused crashes when executing the resulting code. The last two bugs were crashes in `dc` that resulted from mishandling of strings. The manpage improvement was done by switching from [ronn][20] to [Pandoc][21] to generate manpages. Pandoc generates much cleaner manpages and doesn't leave blank lines where they shouldn't be. ## 3.0.3 This is a production release that adds one new feature: specific manpages. Before this release, `bc` and `dc` only used one manpage each that referred to various build options. This release changes it so there is one manpage set per relevant build type. Each manual only has information about its particular build, and `configure.sh` selects the correct set for install. ## 3.0.2 This is a production release that adds `utf8` locale symlinks and removes an unused `auto` variable from the `ceil()` function in the [extended math library][16]. Users do ***NOT*** need to update unless they want the locales. ## 3.0.1 This is a production release with two small changes. Users do ***NOT*** need to upgrade to this release; however, if they haven't upgraded to `3.0.0` yet, it may be worthwhile to upgrade to this release. The first change is fixing a compiler warning on FreeBSD with strict warnings on. The second change is to make the new implementation of `ceil()` in `lib2.bc` much more efficient. ## 3.0.0 *Notes for package maintainers:* *First, the `2.7.0` release series saw a change in the option parsing. This made me change one error message and add a few others. The error message that was changed removed one format specifier. This means that `printf()` will seqfault on old locale files. Unfortunately, `bc` cannot use any locale files except the global ones that are already installed, so it will use the previous ones while running tests during install. **If `bc` segfaults while running arg tests when updating, it is because the global locale files have not been replaced. Make sure to either prevent the test suite from running on update or remove the old locale files before updating.** (Removing the locale files can be done with `make uninstall` or by running the [`locale_uninstall.sh`][22] script.) Once this is done, `bc` should install without problems.* *Second, **the option to build without signal support has been removed**. See below for the reasons why.* This is a production release with some small bug fixes, a few improvements, three major bug fixes, and a complete redesign of `bc`'s error and signal handling. **Users and package maintainers should update to this version as soon as possible.** The first major bug fix was in how `bc` executed files. Previously, a whole file was parsed before it was executed, but if a function is defined *after* code, especially if the function definition was actually a redefinition, and the code before the definition referred to the previous function, this `bc` would replace the function before executing any code. The fix was to make sure that all code that existed before a function definition was executed. The second major bug fix was in `bc`'s `lib2.bc`. The `ceil()` function had a bug where a `0` in the decimal place after the truncation position, caused it to output the wrong numbers if there was any non-zero digit after. The third major bug is that when passing parameters to functions, if an expression included an array (not an array element) as a parameter, it was accepted, when it should have been rejected. It is now correctly rejected. Beyond that, this `bc` got several improvements that both sped it up, improved the handling of signals, and improved the error handling. First, the requirements for `bc` were pushed back to POSIX 2008. `bc` uses one function, `strdup()`, which is not in POSIX 2001, and it is in the X/Open System Interfaces group 2001. It is, however, in POSIX 2008, and since POSIX 2008 is old enough to be supported anywhere that I care, that should be the requirement. Second, the BcVm global variable was put into `bss`. This actually slightly reduces the size of the executable from a massive code shrink, and it will stop `bc` from allocating a large set of memory when `bc` starts. Third, the default Karatsuba length was updated from 64 to 32 after making the optimization changes below, since 32 is going to be better than 64 after the changes. Fourth, Spanish translations were added. Fifth, the interpreter received a speedup to make performance on non-math-heavy scripts more competitive with GNU `bc`. While improvements did, in fact, get it much closer (see the [benchmarks][19]), it isn't quite there. There were several things done to speed up the interpreter: First, several small inefficiencies were removed. These inefficiencies included calling the function `bc_vec_pop(v)` twice instead of calling `bc_vec_npop(v, 2)`. They also included an extra function call for checking the size of the stack and checking the size of the stack more than once on several operations. Second, since the current `bc` function is the one that stores constants and strings, the program caches pointers to the current function's vectors of constants and strings to prevent needing to grab the current function in order to grab a constant or a string. Third, `bc` tries to reuse `BcNum`'s (the internal representation of arbitary-precision numbers). If a `BcNum` has the default capacity of `BC_NUM_DEF_SIZE` (32 on 64-bit and 16 on 32-bit) when it is freed, it is added to a list of available `BcNum`'s. And then, when a `BcNum` is allocated with a capacity of `BC_NUM_DEF_SIZE` and any `BcNum`'s exist on the list of reusable ones, one of those ones is grabbed instead. In order to support these changes, the `BC_NUM_DEF_SIZE` was changed. It used to be 16 bytes on all systems, but it was changed to more closely align with the minimum allocation size on Linux, which is either 32 bytes (64-bit musl), 24 bytes (64-bit glibc), 16 bytes (32-bit musl), or 12 bytes (32-bit glibc). Since these are the minimum allocation sizes, these are the sizes that would be allocated anyway, making it worth it to just use the whole space, so the value of `BC_NUM_DEF_SIZE` on 64-bit systems was changed to 32 bytes. On top of that, at least on 64-bit, `BC_NUM_DEF_SIZE` supports numbers with either 72 integer digits or 45 integer digits and 27 fractional digits. This should be more than enough for most cases since `bc`'s default `scale` values are 0 or 20, meaning that, by default, it has at most 20 fractional digits. And 45 integer digits are *a lot*; it's enough to calculate the amount of mass in the Milky Way galaxy in kilograms. Also, 72 digits is enough to calculate the diameter of the universe in Planck lengths. (For 32-bit, these numbers are either 32 integer digits or 12 integer digits and 20 fractional digits. These are also quite big, and going much bigger on a 32-bit system seems a little pointless since 12 digits is just under a trillion and 20 fractional digits is still enough for about any use since `10^-20` light years is just under a millimeter.) All of this together means that for ordinary uses, and even uses in scientific work, the default number size will be all that is needed, which means that nearly all, if not all, numbers will be reused, relieving pressure on the system allocator. I did several experiments to find the changes that had the most impact, especially with regard to reusing `BcNum`'s. One was putting `BcNum`'s into buckets according to their capacity in powers of 2 up to 512. That performed worse than `bc` did in `2.7.2`. Another was putting any `BcNum` on the reuse list that had a capacity of `BC_NUM_DEF_SIZE * 2` and reusing them for `BcNum`'s that requested `BC_NUM_DEF_SIZE`. This did reduce the amount of time spent, but it also spent a lot of time in the system allocator for an unknown reason. (When using `strace`, a bunch more `brk` calls showed up.) Just reusing `BcNum`'s that had exactly `BC_NUM_DEF_SIZE` capacity spent the smallest amount of time in both user and system time. This makes sense, especially with the changes to make `BC_NUM_DEF_SIZE` bigger on 64-bit systems, since the vast majority of numbers will only ever use numbers with a size less than or equal to `BC_NUM_DEF_SIZE`. Last of all, `bc`'s signal handling underwent a complete redesign. (This is the reason that this version is `3.0.0` and not `2.8.0`.) The change was to move from a polling approach to signal handling to an interrupt-based approach. Previously, every single loop condition had a check for signals. I suspect that this could be expensive when in tight loops. Now, the signal handler just uses `longjmp()` (actually `siglongjmp()`) to start an unwinding of the stack until it is stopped or the stack is unwound to `main()`, which just returns. If `bc` is currently executing code that cannot be safely interrupted (according to POSIX), then signals are "locked." The signal handler checks if the lock is taken, and if it is, it just sets the status to indicate that a signal arrived. Later, when the signal lock is released, the status is checked to see if a signal came in. If so, the stack unwinding starts. This design eliminates polling in favor of maintaining a stack of `jmp_buf`'s. This has its own performance implications, but it gives better interaction. And the cost of pushing and popping a `jmp_buf` in a function is paid at most twice. Most functions do not pay that price, and most of the rest only pay it once. (There are only some 3 functions in `bc` that push and pop a `jmp_buf` twice.) As a side effect of this change, I had to eliminate the use of `stdio.h` in `bc` because `stdio` does not play nice with signals and `longjmp()`. I implemented custom I/O buffer code that takes a fraction of the size. This means that static builds will be smaller, but non-static builds will be bigger, though they will have less linking time. This change is also good because my history implementation was already bypassing `stdio` for good reasons, and unifying the architecture was a win. Another reason for this change is that my `bc` should *always* behave correctly in the presence of signals like `SIGINT`, `SIGTERM`, and `SIGQUIT`. With the addition of my own I/O buffering, I needed to also make sure that the buffers were correctly flushed even when such signals happened. For this reason, I **removed the option to build without signal support**. As a nice side effect of this change, the error handling code could be changed to take advantage of the stack unwinding that signals used. This means that signals and error handling use the same code paths, which means that the stack unwinding is well-tested. (Errors are tested heavily in the test suite.) It also means that functions do not need to return a status code that ***every*** caller needs to check. This eliminated over 100 branches that simply checked return codes and then passed that return code up the stack if necessary. The code bloat savings from this is at least 1700 bytes on `x86_64`, *before* taking into account the extra code from removing `stdio.h`. ## 2.7.2 This is a production release with one major bug fix. The `length()` built-in function can take either a number or an array. If it takes an array, it returns the length of the array. Arrays can be passed by reference. The bug is that the `length()` function would not properly dereference arrays that were references. This is a bug that affects all users. **ALL USERS SHOULD UPDATE `bc`**. ## 2.7.1 This is a production release with fixes for new locales and fixes for compiler warnings on FreeBSD. ## 2.7.0 This is a production release with a bug fix for Linux, new translations, and new features. Bug fixes: * Option parsing in `BC_ENV_ARGS` was broken on Linux in 2.6.1 because `glibc`'s `getopt_long()` is broken. To get around that, and to support long options on every platform, an adapted version of [`optparse`][17] was added. Now, `bc` does not even use `getopt()`. * Parsing `BC_ENV_ARGS` with quotes now works. It isn't the smartest, but it does the job if there are spaces in file names. The following new languages are supported: * Dutch * Polish * Russian * Japanes * Simplified Chinese All of these translations were generated using [DeepL][18], so improvements are welcome. There is only one new feature: **`bc` now has a built-in pseudo-random number generator** (PRNG). The PRNG is seeded, making it useful for applications where `/dev/urandom` does not work because output needs to be reproducible. However, it also uses `/dev/urandom` to seed itself by default, so it will start with a good seed by default. It also outputs 32 bits on 32-bit platforms and 64 bits on 64-bit platforms, far better than the 15 bits of C's `rand()` and `bash`'s `$RANDOM`. In addition, the PRNG can take a bound, and when it gets a bound, it automatically adjusts to remove bias. It can also generate numbers of arbitrary size. (As of the time of release, the largest pseudo-random number generated by this `bc` was generated with a bound of `2^(2^20)`.) ***IMPORTANT: read the [`bc` manual][9] and the [`dc` manual][10] to find out exactly what guarantees the PRNG provides. The underlying implementation is not guaranteed to stay the same, but the guarantees that it provides are guaranteed to stay the same regardless of the implementation.*** On top of that, four functions were added to `bc`'s [extended math library][16] to make using the PRNG easier: * `frand(p)`: Generates a number between `[0,1)` to `p` decimal places. * `ifrand(i, p)`: Generates an integer with bound `i` and adds it to `frand(p)`. * `srand(x)`: Randomizes the sign of `x`. In other words, it flips the sign of `x` with probability `0.5`. * `brand()`: Returns a random boolean value (either `0` or `1`). ## 2.6.1 This is a production release with a bug fix for FreeBSD. The bug was that when `bc` was built without long options, it would give a fatal error on every run. This was caused by a mishandling of `optind`. ## 2.6.0 This release is a production release ***with no bugfixes***. If you do not want to upgrade, you don't have to. No source code changed; the only thing that changed was `lib2.bc`. This release adds one function to the [extended math library][16]: `p(x, y)`, which calculates `x` to the power of `y`, whether or not `y` is an integer. (The `^` operator can only accept integer powers.) This release also includes a couple of small tweaks to the [extended math library][16], mostly to fix returning numbers with too high of `scale`. ## 2.5.3 This release is a production release which addresses inconsistencies in the Portuguese locales. No `bc` code was changed. The issues were that the ISO files used different naming, and also that the files that should have been symlinks were not. I did not catch that because GitHub rendered them the exact same way. ## 2.5.2 This release is a production release. No code was changed, but the build system was changed to allow `CFLAGS` to be given to `CC`, like this: ``` CC="gcc -O3 -march=native" ./configure.sh ``` If this happens, the flags are automatically put into `CFLAGS`, and the compiler is set appropriately. In the example above this means that `CC` will be "gcc" and `CFLAGS` will be "-O3 -march=native". This behavior was added to conform to GNU autotools practices. ## 2.5.1 This is a production release which addresses portability concerns discovered in the `bc` build system. No `bc` code was changed. * Support for Solaris SPARC and AIX were added. * Minor documentations edits were performed. * An option for `configure.sh` was added to disable long options if `getopt_long()` is missing. ## 2.5.0 This is a production release with new translations. No code changed. The translations were contributed by [bugcrazy][15], and they are for Portuguese, both Portugal and Brazil locales. ## 2.4.0 This is a production release primarily aimed at improving `dc`. * A couple of copy and paste errors in the [`dc` manual][10] were fixed. * `dc` startup was optimized by making sure it didn't have to set up `bc`-only things. * The `bc` `&&` and `||` operators were made available to `dc` through the `M` and `m` commands, respectively. * `dc` macros were changed to be tail call-optimized. The last item, tail call optimization, means that if the last thing in a macro is a call to another macro, then the old macro is popped before executing the new macro. This change was made to stop `dc` from consuming more and more memory as macros are executed in a loop. The `q` and `Q` commands still respect the "hidden" macros by way of recording how many macros were removed by tail call optimization. ## 2.3.2 This is a production release meant to fix warnings in the Gentoo `ebuild` by making it possible to disable binary stripping. Other users do *not* need to upgrade. ## 2.3.1 This is a production release. It fixes a bug that caused `-1000000000 < -1` to return `0`. This only happened with negative numbers and only if the value on the left was more negative by a certain amount. That said, this bug *is* a bad bug, and needs to be fixed. **ALL USERS SHOULD UPDATE `bc`**. ## 2.3.0 This is a production release with changes to the build system. ## 2.2.0 This release is a production release. It only has new features and performance improvements. 1. The performance of `sqrt(x)` was improved. 2. The new function `root(x, n)` was added to the extended math library to calculate `n`th roots. 3. The new function `cbrt(x)` was added to the extended math library to calculate cube roots. ## 2.1.3 This is a non-critical release; it just changes the build system, and in non-breaking ways: 1. Linked locale files were changed to link to their sources with a relative link. 2. A bug in `configure.sh` that caused long option parsing to fail under `bash` was fixed. ## 2.1.2 This release is not a critical release. 1. A few codes were added to history. 2. Multiplication was optimized a bit more. 3. Addition and subtraction were both optimized a bit more. ## 2.1.1 This release contains a fix for the test suite made for Linux from Scratch: now the test suite prints `pass` when a test is passed. Other than that, there is no change in this release, so distros and other users do not need to upgrade. ## 2.1.0 This release is a production release. The following bugs were fixed: 1. A `dc` bug that caused stack mishandling was fixed. 2. A warning on OpenBSD was fixed. 3. Bugs in `ctrl+arrow` operations in history were fixed. 4. The ability to paste multiple lines in history was added. 5. A `bc` bug, mishandling of array arguments to functions, was fixed. 6. A crash caused by freeing the wrong pointer was fixed. 7. A `dc` bug where strings, in a rare case, were mishandled in parsing was fixed. In addition, the following changes were made: 1. Division was slightly optimized. 2. An option was added to the build to disable printing of prompts. 3. The special case of empty arguments is now handled. This is to prevent errors in scripts that end up passing empty arguments. 4. A harmless bug was fixed. This bug was that, with the pop instructions (mostly) removed (see below), `bc` would leave extra values on its stack for `void` functions and in a few other cases. These extra items would not affect anything put on the stack and would not cause any sort of crash or even buggy behavior, but they would cause `bc` to take more memory than it needed. On top of the above changes, the following optimizations were added: 1. The need for pop instructions in `bc` was removed. 2. Extra tests on every iteration of the interpreter loop were removed. 3. Updating function and code pointers on every iteration of the interpreter loop was changed to only updating them when necessary. 4. Extra assignments to pointers were removed. Altogether, these changes sped up the interpreter by around 2x. ***NOTE***: This is the last release with new features because this `bc` is now considered complete. From now on, only bug fixes and new translations will be added to this `bc`. ## 2.0.3 This is a production, bug-fix release. Two bugs were fixed in this release: 1. A rare and subtle signal handling bug was fixed. 2. A misbehavior on `0` to a negative power was fixed. The last bug bears some mentioning. When I originally wrote power, I did not thoroughly check its error cases; instead, I had it check if the first number was `0` and then if so, just return `0`. However, `0` to a negative power means that `1` will be divided by `0`, which is an error. I caught this, but only after I stopped being cocky. You see, sometime later, I had noticed that GNU `bc` returned an error, correctly, but I thought it was wrong simply because that's not what my `bc` did. I saw it again later and had a double take. I checked for real, finally, and found out that my `bc` was wrong all along. That was bad on me. But the bug was easy to fix, so it is fixed now. There are two other things in this release: 1. Subtraction was optimized by [Stefan Eßer][14]. 2. Division was also optimized, also by Stefan Eßer. ## 2.0.2 This release contains a fix for a possible overflow in the signal handling. I would be surprised if any users ran into it because it would only happen after 2 billion (`2^31-1`) `SIGINT`'s, but I saw it and had to fix it. ## 2.0.1 This release contains very few things that will apply to any users. 1. A slight bug in `dc`'s interactive mode was fixed. 2. A bug in the test suite that was only triggered on NetBSD was fixed. 3. **The `-P`/`--no-prompt` option** was added for users that do not want a prompt. 4. A `make check` target was added as an alias for `make test`. 5. `dc` got its own read prompt: `?> `. ## 2.0.0 This release is a production release. This release is also a little different from previous releases. From here on out, I do not plan on adding any more features to this `bc`; I believe that it is complete. However, there may be bug fix releases in the future, if I or any others manage to find bugs. This release has only a few new features: 1. `atan2(y, x)` was added to the extended math library as both `a2(y, x)` and `atan2(y, x)`. 2. Locales were fixed. 3. A **POSIX shell-compatible script was added as an alternative to compiling `gen/strgen.c`** on a host machine. More details about making the choice between the two can be found by running `./configure.sh --help` or reading the [build manual][13]. 4. Multiplication was optimized by using **diagonal multiplication**, rather than straight brute force. 5. The `locale_install.sh` script was fixed. 6. `dc` was given the ability to **use the environment variable `DC_ENV_ARGS`**. 7. `dc` was also given the ability to **use the `-i` or `--interactive`** options. 8. Printing the prompt was fixed so that it did not print when it shouldn't. 9. Signal handling was fixed. 10. **Handling of `SIGTERM` and `SIGQUIT`** was fixed. 11. The **built-in functions `maxibase()`, `maxobase()`, and `maxscale()`** (the commands `T`, `U`, `V` in `dc`, respectively) were added to allow scripts to query for the max allowable values of those globals. 12. Some incompatibilities with POSIX were fixed. In addition, this release is `2.0.0` for a big reason: the internal format for numbers changed. They used to be a `char` array. Now, they are an array of larger integers, packing more decimal digits into each integer. This has delivered ***HUGE*** performance improvements, especially for multiplication, division, and power. This `bc` should now be the fastest `bc` available, but I may be wrong. ## 1.2.8 This release contains a fix for a harmless bug (it is harmless in that it still works, but it just copies extra data) in the [`locale_install.sh`][12] script. ## 1.2.7 This version contains fixes for the build on Arch Linux. ## 1.2.6 This release removes the use of `local` in shell scripts because it's not POSIX shell-compatible, and also updates a man page that should have been updated a long time ago but was missed. ## 1.2.5 This release contains some missing locale `*.msg` files. ## 1.2.4 This release contains a few bug fixes and new French translations. ## 1.2.3 This release contains a fix for a bug: use of uninitialized data. Such data was only used when outputting an error message, but I am striving for perfection. As Michelangelo said, "Trifles make perfection, and perfection is no trifle." ## 1.2.2 This release contains fixes for OpenBSD. ## 1.2.1 This release contains bug fixes for some rare bugs. ## 1.2.0 This is a production release. There have been several changes since `1.1.0`: 1. The build system had some changes. 2. Locale support has been added. (Patches welcome for translations.) 3. **The ability to turn `ibase`, `obase`, and `scale` into stacks** was added with the `-g` command-line option. (See the [`bc` manual][9] for more details.) 4. Support for compiling on Mac OSX out of the box was added. 5. The extended math library got `t(x)`, `ceil(x)`, and some aliases. 6. The extended math library also got `r2d(x)` (for converting from radians to degrees) and `d2r(x)` (for converting from degrees to radians). This is to allow using degrees with the standard library. 7. Both calculators now accept numbers in **scientific notation**. See the [`bc` manual][9] and the [`dc` manual][10] for details. 8. Both calculators can **output in either scientific or engineering notation**. See the [`bc` manual][9] and the [`dc` manual][10] for details. 9. Some inefficiencies were removed. 10. Some bugs were fixed. 11. Some bugs in the extended library were fixed. 12. Some defects from [Coverity Scan][11] were fixed. ## 1.1.4 This release contains a fix to the build system that allows it to build on older versions of `glibc`. ## 1.1.3 This release contains a fix for a bug in the test suite where `bc` tests and `dc` tests could not be run in parallel. ## 1.1.2 This release has a fix for a history bug; the down arrow did not work. ## 1.1.1 This release fixes a bug in the `1.1.0` build system. The source is exactly the same. The bug that was fixed was a failure to install if no `EXECSUFFIX` was used. ## 1.1.0 This is a production release. However, many new features were added since `1.0`. 1. **The build system has been changed** to use a custom, POSIX shell-compatible configure script ([`configure.sh`][6]) to generate a POSIX make-compatible `Makefile`, which means that `bc` and `dc` now build out of the box on any POSIX-compatible system. 2. Out-of-memory and output errors now cause the `bc` to report the error, clean up, and die, rather than just reporting and trying to continue. 3. **Strings and constants are now garbage collected** when possible. 4. Signal handling and checking has been made more simple and more thorough. 5. `BcGlobals` was refactored into `BcVm` and `BcVm` was made global. Some procedure names were changed to reflect its difference to everything else. 6. Addition got a speed improvement. 7. Some common code for addition and multiplication was refactored into its own procedure. 8. A bug was removed where `dc` could have been selected, but the internal `#define` that returned `true` for a query about `dc` would not have returned `true`. 9. Useless calls to `bc_num_zero()` were removed. 10. **History support was added.** The history support is based off of a [UTF-8 aware fork][7] of [`linenoise`][8], which has been customized with `bc`'s own data structures and signal handling. 11. Generating C source from the math library now removes tabs from the library, shrinking the size of the executable. 12. The math library was shrunk. 13. Error handling and reporting was improved. 14. Reallocations were reduced by giving access to the request size for each operation. 15. **`abs()` (`b` command for `dc`) was added as a builtin.** 16. Both calculators were tested on FreeBSD. 17. Many obscure parse bugs were fixed. 18. Markdown and man page manuals were added, and the man pages are installed by `make install`. 19. Executable size was reduced, though the added features probably made the executable end up bigger. 20. **GNU-style array references were added as a supported feature.** 21. Allocations were reduced. 22. **New operators were added**: `$` (`$` for `dc`), `@` (`@` for `dc`), `@=`, `<<` (`H` for `dc`), `<<=`, `>>` (`h` for `dc`), and `>>=`. See the [`bc` manual][9] and the [`dc` manual][10] for more details. 23. **An extended math library was added.** This library contains code that makes it so I can replace my desktop calculator with this `bc`. See the [`bc` manual][3] for more details. 24. Support for all capital letters as numbers was added. 25. **Support for GNU-style void functions was added.** 26. A bug fix for improper handling of function parameters was added. 27. Precedence for the or (`||`) operator was changed to match GNU `bc`. 28. `dc` was given an explicit negation command. 29. `dc` was changed to be able to handle strings in arrays. ## 1.1 Release Candidate 3 This release is the eighth release candidate for 1.1, though it is the third release candidate meant as a general release candidate. The new code has not been tested as thoroughly as it should for release. ## 1.1 Release Candidate 2 This release is the seventh release candidate for 1.1, though it is the second release candidate meant as a general release candidate. The new code has not been tested as thoroughly as it should for release. ## 1.1 FreeBSD Beta 5 This release is the sixth release candidate for 1.1, though it is the fifth release candidate meant specifically to test if `bc` works on FreeBSD. The new code has not been tested as thoroughly as it should for release. ## 1.1 FreeBSD Beta 4 This release is the fifth release candidate for 1.1, though it is the fourth release candidate meant specifically to test if `bc` works on FreeBSD. The new code has not been tested as thoroughly as it should for release. ## 1.1 FreeBSD Beta 3 This release is the fourth release candidate for 1.1, though it is the third release candidate meant specifically to test if `bc` works on FreeBSD. The new code has not been tested as thoroughly as it should for release. ## 1.1 FreeBSD Beta 2 This release is the third release candidate for 1.1, though it is the second release candidate meant specifically to test if `bc` works on FreeBSD. The new code has not been tested as thoroughly as it should for release. ## 1.1 FreeBSD Beta 1 This release is the second release candidate for 1.1, though it is meant specifically to test if `bc` works on FreeBSD. The new code has not been tested as thoroughly as it should for release. ## 1.1 Release Candidate 1 This is the first release candidate for 1.1. The new code has not been tested as thoroughly as it should for release. ## 1.0 This is the first non-beta release. `bc` is ready for production use. As such, a lot has changed since 0.5. 1. `dc` has been added. It has been tested even more thoroughly than `bc` was for `0.5`. It does not have the `!` command, and for security reasons, it never will, so it is complete. 2. `bc` has been more thoroughly tested. An entire section of the test suite (for both programs) has been added to test for errors. 3. A prompt (`>>> `) has been added for interactive mode, making it easier to see inputs and outputs. 4. Interrupt handling has been improved, including elimination of race conditions (as much as possible). 5. MinGW and [Windows Subsystem for Linux][1] support has been added (see [xstatic][2] for binaries). 6. Memory leaks and errors have been eliminated (as far as ASan and Valgrind can tell). 7. Crashes have been eliminated (as far as [afl][3] can tell). 8. Karatsuba multiplication was added (and thoroughly) tested, speeding up multiplication and power by orders of magnitude. 9. Performance was further enhanced by using a "divmod" function to reduce redundant divisions and by removing superfluous `memset()` calls. 10. To switch between Karatsuba and `O(n^2)` multiplication, the config variable `BC_NUM_KARATSUBA_LEN` was added. It is set to a sane default, but the optimal number can be found with [`karatsuba.py`][4] (requires Python 3) and then configured through `make`. 11. The random math test generator script was changed to Python 3 and improved. `bc` and `dc` have together been run through 30+ million random tests. 12. All known math bugs have been fixed, including out of control memory allocations in `sine` and `cosine` (that was actually a parse bug), certain cases of infinite loop on square root, and slight inaccuracies (as much as possible; see the [README][5]) in transcendental functions. 13. Parsing has been fixed as much as possible. 14. Test coverage was improved to 94.8%. The only paths not covered are ones that happen when `malloc()` or `realloc()` fails. 15. An extension to get the length of an array was added. 16. The boolean not (`!`) had its precedence change to match negation. 17. Data input was hardened. 18. `bc` was made fully compliant with POSIX when the `-s` flag is used or `POSIXLY_CORRECT` is defined. 19. Error handling was improved. 20. `bc` now checks that files it is given are not directories. ## 1.0 Release Candidate 7 This is the seventh release candidate for 1.0. It fixes a few bugs in 1.0 Release Candidate 6. ## 1.0 Release Candidate 6 This is the sixth release candidate for 1.0. It fixes a few bugs in 1.0 Release Candidate 5. ## 1.0 Release Candidate 5 This is the fifth release candidate for 1.0. It fixes a few bugs in 1.0 Release Candidate 4. ## 1.0 Release Candidate 4 This is the fourth release candidate for 1.0. It fixes a few bugs in 1.0 Release Candidate 3. ## 1.0 Release Candidate 3 This is the third release candidate for 1.0. It fixes a few bugs in 1.0 Release Candidate 2. ## 1.0 Release Candidate 2 This is the second release candidate for 1.0. It fixes a few bugs in 1.0 Release Candidate 1. ## 1.0 Release Candidate 1 This is the first Release Candidate for 1.0. `bc` is complete, with `dc`, but it is not tested. ## 0.5 This beta release completes more features, but it is still not complete nor tested as thoroughly as necessary. ## 0.4.1 This beta release fixes a few bugs in 0.4. ## 0.4 This is a beta release. It does not have the complete set of features, and it is not thoroughly tested. [1]: https://docs.microsoft.com/en-us/windows/wsl/install-win10 [2]: https://pkg.musl.cc/bc/ [3]: http://lcamtuf.coredump.cx/afl/ [4]: ./scripts/karatsuba.py [5]: ./README.md [6]: ./configure.sh [7]: https://github.com/rain-1/linenoise-mob [8]: https://github.com/antirez/linenoise [9]: ./manuals/bc/A.1.md [10]: ./manuals/dc/A.1.md [11]: https://scan.coverity.com/projects/gavinhoward-bc [12]: ./scripts/locale_install.sh [13]: ./manuals/build.md [14]: https://github.com/stesser [15]: https://github.com/bugcrazy [16]: ./manuals/bc/A.1.md#extended-library [17]: https://github.com/skeeto/optparse [18]: https://www.deepl.com/translator [19]: ./manuals/benchmarks.md [20]: https://github.com/apjanke/ronn-ng [21]: https://pandoc.org/ [22]: ./scripts/locale_uninstall.sh diff --git a/contrib/bc/README.md b/contrib/bc/README.md index c46d66b7e3ea..259ab923bfc4 100644 --- a/contrib/bc/README.md +++ b/contrib/bc/README.md @@ -1,419 +1,441 @@ # `bc` ***WARNING: This project has moved to [https://git.yzena.com/][20] for [these reasons][21], though GitHub will remain a mirror.*** This is an implementation of the [POSIX `bc` calculator][12] that implements [GNU `bc`][1] extensions, as well as the period (`.`) extension for the BSD flavor of `bc`. For more information, see this `bc`'s full manual. This `bc` also includes an implementation of `dc` in the same binary, accessible via a symbolic link, which implements all FreeBSD and GNU extensions. (If a standalone `dc` binary is desired, `bc` can be copied and renamed to `dc`.) The `!` command is omitted; I believe this poses security concerns and that such functionality is unnecessary. For more information, see the `dc`'s full manual. This `bc` also provides `bc`'s math as a library with C bindings, called `bcl`. For more information, see the full manual for `bcl`. ## License This `bc` is Free and Open Source Software (FOSS). It is offered under the BSD 2-clause License. Full license text may be found in the [`LICENSE.md`][4] file. ## Prerequisites This `bc` only requires either: 1. Windows 10 or later, or 2. A C99-compatible compiler and a (mostly) POSIX 2008-compatible system with the XSI (X/Open System Interfaces) option group. Since POSIX 2008 with XSI requires the existence of a C99 compiler as `c99`, any POSIX and XSI-compatible system will have everything needed. POSIX-compatible systems that are known to work: * Linux * FreeBSD * OpenBSD * NetBSD * Mac OSX * Solaris* (as long as the Solaris version supports POSIX 2008) * AIX * HP-UX* (except for history) In addition, there is compatibility code to make this `bc` work on Windows. Please submit bug reports if this `bc` does not build out of the box on any system. ## Build This `bc` should build unmodified on any POSIX-compliant system or on Windows starting with Windows 10 (though earlier versions may work). -For more complex build requirements than the ones below, see the -[build manual][5]. +For more complex build requirements than the ones below, see the [build +manual][5]. ### Windows There is no guarantee that this `bc` will work on any version of Windows earlier than Windows 10 (I cannot test on earlier versions), but it is guaranteed to work on Windows 10 at least. Also, if building with MSBuild, the MSBuild bundled with Visual Studio is required. **Note**: Unlike the POSIX-compatible platforms, only one build configuration is supported on Windows: extra math and prompt enabled, history and NLS (locale support) disabled, with both calculators built. #### `bc` -To build `bc`, you can open the `bc.sln` file in Visual Studio, select the +To build `bc`, you can open the `vs/bc.sln` file in Visual Studio, select the configuration, and build. You can also build using MSBuild with the following from the root directory: ``` -msbuild -property:Configuration= bc.sln +msbuild -property:Configuration= vs/bc.sln ``` where `` is either one of `Debug` or `Release`. +On Windows, the calculators are built as `vs/bin///bc.exe` and +`vs/bin///dc.exe`, where `` can be either `Win32` or +`x64`, and `` can be `Debug` or `Release`. + +**Note**: On Windows, `dc.exe` is just copied from `bc.exe`; it is not linked. +Patches are welcome for a way to do that. + #### `bcl` (Library) -To build the library, you can open the `bcl.sln` file in Visual Studio, select -the configuration, and build. +To build the library, you can open the `vs/bcl.sln` file in Visual Studio, +select the configuration, and build. You can also build using MSBuild with the following from the root directory: ``` -msbuild -property:Configuration= bcl.sln +msbuild -property:Configuration= vs/bcl.sln ``` -where `` is either one of `Debug` or `Release`. +where `` is either one of `Debug`, `ReleaseMD`, or `ReleaseMT`. + +On Windows, the library is built as `vs/lib///bcl.lib`, where +`` can be either `Win32` or `x64`, and `` can be `Debug`, +`ReleaseMD`, or `ReleaseMT`. ### POSIX-Compatible Systems On POSIX-compatible systems, `bc` is built as `bin/bc` and `dc` is built as -`bin/dc` by default. On Windows, they are built as `Release/bc/bc.exe` and -`Release/bc/dc.exe`. - -**Note**: On Windows, `dc.exe` is just copied from `bc.exe`; it is not linked. -Patches are welcome for a way to do that. +`bin/dc` by default. #### Default For the default build with optimization, use the following commands in the root directory: ``` ./configure.sh -O3 make ``` #### One Calculator To only build `bc`, use the following commands: ``` ./configure.sh --disable-dc make ``` To only build `dc`, use the following commands: ``` ./configure.sh --disable-bc make ``` #### Debug For debug builds, use the following commands in the root directory: ``` ./configure.sh -g make ``` #### Install To install, use the following command: ``` make install ``` By default, `bc` and `dc` will be installed in `/usr/local`. For installing in other locations, use the `PREFIX` environment variable when running `configure.sh` or pass the `--prefix=` option to `configure.sh`. See the [build manual][5], or run `./configure.sh --help`, for more details. #### Library This `bc` does provide a way to build a math library with C bindings. This is done by the `-a` or `--library` options to `configure.sh`: ``` ./configure.sh -a ``` When building the library, the executables are not built. For more information, see the [build manual][5]. The library API can be found in [`manuals/bcl.3.md`][26] or `man bcl` once the library is installed. The library is built as `bin/libbcl.a` on POSIX-compatible systems or as `Release/bcl/bcl.lib` on Windows. #### Package and Distro Maintainers +This section is for package and distro maintainers. + +##### Out-of-Source Builds + +Out-of-source builds are supported; just call `configure.sh` from the directory +where the actual build will happen. + +For example, if the source is in `bc`, the build should happen in `build`, then +call `configure.sh` and `make` like so: + +``` +../bc/configure.sh +make +``` + +***WARNING***: The path to `configure.sh` from the build directory must not have +spaces because `make` does not support target names with spaces. + ##### Recommended Compiler When I ran benchmarks with my `bc` compiled under `clang`, it performed much better than when compiled under `gcc`. I recommend compiling this `bc` with `clang`. I also recommend building this `bc` with C11 if you can because `bc` will detect a C11 compiler and add `_Noreturn` to any relevant function(s). ##### Recommended Optimizations I wrote this `bc` with Separation of Concerns, which means that there are many small functions that could be inlined. However, they are often called across file boundaries, and the default optimizer can only look at the current file, which means that they are not inlined. Thus, because of the way this `bc` is built, it will automatically be slower than other `bc` implementations when running scripts with no math. (My `bc`'s math is *much* faster, so any non-trivial script should run faster in my `bc`.) Some, or all, of the difference can be made up with the right optimizations. The optimizations I recommend are: 1. `-O3` 2. `-flto` (link-time optimization) in that order. Link-time optimization, in particular, speeds up the `bc` a lot. This is because when link-time optimization is turned on, the optimizer can look across files and inline *much* more heavily. However, I recommend ***NOT*** using `-march=native`. Doing so will reduce this `bc`'s performance, at least when building with link-time optimization. See the [benchmarks][19] for more details. ##### Stripping Binaries By default, non-debug binaries are stripped, but stripping can be disabled with the `-T` option to `configure.sh`. ##### Using This `bc` as an Alternative If this `bc` is packaged as an alternative to an already existing `bc` package, it is possible to rename it in the build to prevent name collision. To prepend to the name, just run the following: ``` EXECPREFIX= ./configure.sh ``` To append to the name, just run the following: ``` EXECSUFFIX= ./configure.sh ``` If a package maintainer wishes to add both a prefix and a suffix, that is allowed. **Note**: The suggested name (and package name) when `bc` is not available is `bc-gh`. ##### Karatsuba Number Package and distro maintainers have one tool at their disposal to build this `bc` in the optimal configuration: `scripts/karatsuba.py`. This script is not a compile-time or runtime prerequisite; it is for package and distro maintainers to run once when a package is being created. It finds the optimal Karatsuba number (see the [algorithms manual][7] for more information) for the machine that it is running on. The easiest way to run this script is with `make karatsuba`. If desired, maintainers can also skip running this script because there is a sane default for the Karatsuba number. ## Status This `bc` is robust. It is well-tested, fuzzed, and fully standards-compliant (though not certified) with POSIX `bc`. The math has been tested with 40+ million random problems, so it is as correct as I can make it. This `bc` can be used as a drop-in replacement for any existing `bc`. This `bc` is also compatible with MinGW toolchains, though history is not supported on Windows. In addition, this `bc` is considered complete; i.e., there will be no more releases with additional features. However, it *is* actively maintained, so if any bugs are found, they will be fixed in new releases. Also, additional translations will also be added as they are provided. ### Development If I (Gavin D. Howard) get [hit by a bus][27] and future programmers need to handle work themselves, the best place to start is the [Development manual][28]. ## Vim Syntax I have developed (using other people's code to start) [`vim` syntax files][17] for this `bc` and `dc`, including the extensions. ## `bc` Libs I have gathered some excellent [`bc` and `dc` libraries][18]. These libraries may prove useful to any serious users. ## Comparison to GNU `bc` This `bc` compares favorably to GNU `bc`. * This `bc` builds natively on Windows. * It has more extensions, which make this `bc` more useful for scripting. * This `bc` is a bit more POSIX compliant. * It has a much less buggy parser. The GNU `bc` will give parse errors for what is actually valid `bc` code, or should be. For example, putting an `else` on a new line after a brace can cause GNU `bc` to give a parse error. * This `bc` has fewer crashes. * GNU `bc` calculates the wrong number of significant digits for `length(x)`. * GNU `bc` will sometimes print numbers incorrectly. For example, when running it on the file `tests/bc/power.txt` in this repo, GNU `bc` gets all the right answers, but it fails to wrap the numbers at the proper place when outputting to a file. * This `bc` is faster. (See [Performance](#performance).) ### Performance Because this `bc` packs more than `1` decimal digit per hardware integer, this `bc` is faster than GNU `bc` and can be *much* faster. Full benchmarks can be found at [manuals/benchmarks.md][19]. There is one instance where this `bc` is slower: if scripts are light on math. This is because this `bc`'s intepreter is slightly slower than GNU `bc`, but that is because it is more robust. See the [benchmarks][19]. ## Algorithms To see what algorithms this `bc` uses, see the [algorithms manual][7]. ## Locales Currently, there is no locale support on Windows. Additionally, this `bc` only has support for English (and US English), French, German, Portuguese, Dutch, Polish, Russian, Japanese, and Chinese locales. Patches are welcome for translations; use the existing `*.msg` files in `locales/` as a starting point. In addition, patches for improvements are welcome; the last two messages in Portuguese were made with Google Translate, and the Dutch, Polish, Russian, Japanese, and Chinese locales were all generated with [DeepL][22]. The message files provided assume that locales apply to all regions where a language is used, but this might not be true for, e.g., `fr_CA` and `fr_CH`. Any corrections or a confirmation that the current texts are acceptable for those regions would be appreciated, too. ## Other Projects Other projects based on this bc are: * [busybox `bc`][8]. The busybox maintainers have made their own changes, so any bugs in the busybox `bc` should be reported to them. * [toybox `bc`][9]. The maintainer has also made his own changes, so bugs in the toybox `bc` should be reported there. * [FreeBSD `bc`][23]. While the `bc` in FreeBSD is kept up-to-date, it is better to [report bugs there][24], as well as [submit patches][25], and the maintainers of the package will contact me if necessary. ## Language This `bc` is written in pure ISO C99, using POSIX 2008 APIs with custom Windows compatibility code. ## Commit Messages This `bc` uses the commit message guidelines laid out in [this blog post][10]. ## Semantic Versioning This `bc` uses [semantic versioning][11]. ## Contents Items labeled with `(maintainer use only)` are not included in release source tarballs. Files: .gitignore The git ignore file (maintainer use only). .gitattributes The git attributes file (maintainer use only). - bc.sln The Visual Studio solution file for bc. - bc.vcxproj The Visual Studio project file for bc. - bc.vcxproj.filters The Visual Studio filters file for bc. - bcl.sln The Visual Studio solution file for bcl. - bcl.vcxproj The Visual Studio project file for bcl. - bcl.vcxproj.filters The Visual Studio filters file for bcl. + bcl.pc.in A template pkg-config file for bcl. configure A symlink to configure.sh to make packaging easier. configure.sh The configure script. LICENSE.md A Markdown form of the BSD 2-clause License. Makefile.in The Makefile template. + NEWS.md The changelog. NOTICE.md List of contributors and copyright owners. RELEASE.md A checklist for making a release (maintainer use only). Folders: gen The bc math library, help texts, and code to generate C source. include All header files. locales Locale files, in .msg format. Patches welcome for translations. manuals Manuals for both programs. src All source code. scripts A bunch of shell scripts to help with development and building. tests All tests. + vs Files needed for the build on Windows. [1]: https://www.gnu.org/software/bc/ [4]: ./LICENSE.md [5]: ./manuals/build.md [7]: ./manuals/algorithms.md [8]: https://git.busybox.net/busybox/tree/miscutils/bc.c [9]: https://github.com/landley/toybox/blob/master/toys/pending/bc.c [10]: http://tbaggery.com/2008/04/19/a-note-about-git-commit-messages.html [11]: http://semver.org/ [12]: https://pubs.opengroup.org/onlinepubs/9699919799/utilities/bc.html [17]: https://git.yzena.com/gavin/vim-bc [18]: https://git.yzena.com/gavin/bc_libs [19]: ./manuals/benchmarks.md [20]: https://git.yzena.com/gavin/bc [21]: https://gavinhoward.com/2020/04/i-am-moving-away-from-github/ [22]: https://www.deepl.com/translator [23]: https://cgit.freebsd.org/src/tree/contrib/bc [24]: https://bugs.freebsd.org/ [25]: https://reviews.freebsd.org/ [26]: ./manuals/bcl.3.md [27]: https://en.wikipedia.org/wiki/Bus_factor [28]: ./manuals/development.md diff --git a/contrib/bc/bcl.pc.in b/contrib/bc/bcl.pc.in new file mode 100644 index 000000000000..f440eeca950f --- /dev/null +++ b/contrib/bc/bcl.pc.in @@ -0,0 +1,8 @@ +includedir=%%INCLUDEDIR%% +libdir=%%LIBDIR%% + +Name: bcl +Description: Implemention of arbitrary-precision math from the bc calculator. +Version: %%VERSION%% +Cflags: -I${includedir} +Libs: -L${libdir} -lbcl diff --git a/contrib/bc/configure.sh b/contrib/bc/configure.sh index de1339780073..76ffb2b9a18e 100755 --- a/contrib/bc/configure.sh +++ b/contrib/bc/configure.sh @@ -1,1658 +1,1764 @@ #! /bin/sh # # SPDX-License-Identifier: BSD-2-Clause # # Copyright (c) 2018-2021 Gavin D. Howard and contributors. # # Redistribution and use in source and binary forms, with or without # modification, are permitted provided that the following conditions are met: # # * Redistributions of source code must retain the above copyright notice, this # list of conditions and the following disclaimer. # # * Redistributions in binary form must reproduce the above copyright notice, # this list of conditions and the following disclaimer in the documentation # and/or other materials provided with the distribution. # # THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" # AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE # IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE # ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE # LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR # CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF # SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS # INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN # CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) # ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE # POSSIBILITY OF SUCH DAMAGE. # script="$0" scriptdir=$(dirname "$script") script=$(basename "$script") -. "$scriptdir/scripts/functions.sh" +builddir=$(pwd) -cd "$scriptdir" +. "$scriptdir/scripts/functions.sh" # Simply prints the help message and quits based on the argument. # @param val The value to pass to exit. Must be an integer. usage() { if [ $# -gt 0 ]; then _usage_val=1 printf "%s\n\n" "$1" else _usage_val=0 fi printf 'usage:\n' printf ' %s -h\n' "$script" printf ' %s --help\n' "$script" - printf ' %s [-a|-bD|-dB|-c] [-CEfgGHlmMNPtTvz] [-O OPT_LEVEL] [-k KARATSUBA_LEN]\n' "$script" + printf ' %s [-a|-bD|-dB|-c] [-CEfgGHlmMNtTvz] [-O OPT_LEVEL] [-k KARATSUBA_LEN]\\\n' "$script" + printf ' [-s SETTING] [-S SETTING]\n' printf ' %s \\\n' "$script" printf ' [--library|--bc-only --disable-dc|--dc-only --disable-bc|--coverage] \\\n' printf ' [--force --debug --disable-extra-math --disable-generated-tests] \\\n' printf ' [--disable-history --disable-man-pages --disable-nls --disable-strip] \\\n' printf ' [--install-all-locales] [--opt=OPT_LEVEL] \\\n' printf ' [--karatsuba-len=KARATSUBA_LEN] \\\n' + printf ' [--set-default-on=SETTING] [--set-default-off=SETTING] \\\n' printf ' [--prefix=PREFIX] [--bindir=BINDIR] [--datarootdir=DATAROOTDIR] \\\n' printf ' [--datadir=DATADIR] [--mandir=MANDIR] [--man1dir=MAN1DIR] \\\n' printf '\n' printf ' -a, --library\n' printf ' Build the libbcl instead of the programs. This is meant to be used with\n' printf ' Other software like programming languages that want to make use of the\n' printf ' parsing and math capabilities. This option will install headers using\n' printf ' `make install`.\n' printf ' -b, --bc-only\n' printf ' Build bc only. It is an error if "-d", "--dc-only", "-B", or\n' printf ' "--disable-bc" are specified too.\n' printf ' -B, --disable-bc\n' printf ' Disable bc. It is an error if "-b", "--bc-only", "-D", or "--disable-dc"\n' printf ' are specified too.\n' printf ' -c, --coverage\n' printf ' Generate test coverage code. Requires gcov and gcovr.\n' printf ' It is an error if either "-b" ("-D") or "-d" ("-B") is specified.\n' printf ' Requires a compiler that use gcc-compatible coverage options\n' printf ' -C, --disable-clean\n' printf ' Disable the clean that configure.sh does before configure.\n' printf ' -d, --dc-only\n' printf ' Build dc only. It is an error if "-b", "--bc-only", "-D", or\n' printf ' "--disable-dc" are specified too.\n' printf ' -D, --disable-dc\n' printf ' Disable dc. It is an error if "-d", "--dc-only", "-B", or "--disable-bc"\n' printf ' are specified too.\n' printf ' -E, --disable-extra-math\n' printf ' Disable extra math. This includes: "$" operator (truncate to integer),\n' printf ' "@" operator (set number of decimal places), and r(x, p) (rounding\n' printf ' function). Additionally, this option disables the extra printing\n' printf ' functions in the math library.\n' printf ' -f, --force\n' printf ' Force use of all enabled options, even if they do not work. This\n' printf ' option is to allow the maintainer a way to test that certain options\n' printf ' are not failing invisibly. (Development only.)' printf ' -g, --debug\n' printf ' Build in debug mode. Adds the "-g" flag, and if there are no\n' printf ' other CFLAGS, and "-O" was not given, this also adds the "-O0"\n' printf ' flag. If this flag is *not* given, "-DNDEBUG" is added to CPPFLAGS\n' printf ' and a strip flag is added to the link stage.\n' printf ' -G, --disable-generated-tests\n' printf ' Disable generating tests. This is for platforms that do not have a\n' printf ' GNU bc-compatible bc to generate tests.\n' printf ' -h, --help\n' printf ' Print this help message and exit.\n' printf ' -H, --disable-history\n' printf ' Disable history.\n' printf ' -k KARATSUBA_LEN, --karatsuba-len KARATSUBA_LEN\n' printf ' Set the karatsuba length to KARATSUBA_LEN (default is 64).\n' printf ' It is an error if KARATSUBA_LEN is not a number or is less than 16.\n' printf ' -l, --install-all-locales\n' printf ' Installs all locales, regardless of how many are on the system. This\n' printf ' option is useful for package maintainers who want to make sure that\n' printf ' a package contains all of the locales that end users might need.\n' printf ' -m, --enable-memcheck\n' printf ' Enable memcheck mode, to ensure no memory leaks. For development only.\n' printf ' -M, --disable-man-pages\n' printf ' Disable installing manpages.\n' printf ' -N, --disable-nls\n' printf ' Disable POSIX locale (NLS) support.\n' printf ' -O OPT_LEVEL, --opt OPT_LEVEL\n' printf ' Set the optimization level. This can also be included in the CFLAGS,\n' printf ' but it is provided, so maintainers can build optimized debug builds.\n' printf ' This is passed through to the compiler, so it must be supported.\n' printf ' -s SETTING, --set-default-on SETTING\n' printf ' Set the default named by SETTING to on. See below for possible values\n' printf ' for SETTING. For multiple instances of the -s or -S for the the same\n' printf ' setting, the last one is used.\n' printf ' -S SETTING, --set-default-off SETTING\n' printf ' Set the default named by SETTING to off. See below for possible values\n' printf ' for SETTING. For multiple instances of the -s or -S for the the same\n' printf ' setting, the last one is used.\n' printf ' -t, --enable-test-timing\n' printf ' Enable the timing of tests. This is for development only.\n' printf ' -T, --disable-strip\n' printf ' Disable stripping symbols from the compiled binary or binaries.\n' printf ' Stripping symbols only happens when debug mode is off.\n' printf ' -v, --enable-valgrind\n' printf ' Enable a build appropriate for valgrind. For development only.\n' printf ' -z, --enable-fuzz-mode\n' printf ' Enable fuzzing mode. THIS IS FOR DEVELOPMENT ONLY.\n' printf ' --prefix PREFIX\n' printf ' The prefix to install to. Overrides "$PREFIX" if it exists.\n' printf ' If PREFIX is "/usr", install path will be "/usr/bin".\n' printf ' Default is "/usr/local".\n' printf ' --bindir BINDIR\n' printf ' The directory to install binaries in. Overrides "$BINDIR" if it exists.\n' printf ' Default is "$PREFIX/bin".\n' printf ' --includedir INCLUDEDIR\n' printf ' The directory to install headers in. Overrides "$INCLUDEDIR" if it\n' printf ' exists. Default is "$PREFIX/include".\n' printf ' --libdir LIBDIR\n' printf ' The directory to install libraries in. Overrides "$LIBDIR" if it exists.\n' printf ' Default is "$PREFIX/lib".\n' printf ' --datarootdir DATAROOTDIR\n' printf ' The root location for data files. Overrides "$DATAROOTDIR" if it exists.\n' printf ' Default is "$PREFIX/share".\n' printf ' --datadir DATADIR\n' printf ' The location for data files. Overrides "$DATADIR" if it exists.\n' printf ' Default is "$DATAROOTDIR".\n' printf ' --mandir MANDIR\n' printf ' The location to install manpages to. Overrides "$MANDIR" if it exists.\n' printf ' Default is "$DATADIR/man".\n' printf ' --man1dir MAN1DIR\n' printf ' The location to install Section 1 manpages to. Overrides "$MAN1DIR" if\n' printf ' it exists. Default is "$MANDIR/man1".\n' printf ' --man3dir MAN3DIR\n' printf ' The location to install Section 3 manpages to. Overrides "$MAN3DIR" if\n' printf ' it exists. Default is "$MANDIR/man3".\n' printf '\n' printf 'In addition, the following environment variables are used:\n' printf '\n' printf ' CC C compiler. Must be compatible with POSIX c99. If there is a\n' printf ' space in the basename of the compiler, the items after the\n' printf ' first space are assumed to be compiler flags, and in that case,\n' printf ' the flags are automatically moved into CFLAGS. Default is\n' printf ' "c99".\n' printf ' HOSTCC Host C compiler. Must be compatible with POSIX c99. If there is\n' printf ' a space in the basename of the compiler, the items after the\n' printf ' first space are assumed to be compiler flags, and in the case,\n' printf ' the flags are automatically moved into HOSTCFLAGS. Default is\n' printf ' "$CC".\n' printf ' HOST_CC Same as HOSTCC. If HOSTCC also exists, it is used.\n' printf ' CFLAGS C compiler flags.\n' printf ' HOSTCFLAGS CFLAGS for HOSTCC. Default is "$CFLAGS".\n' printf ' HOST_CFLAGS Same as HOST_CFLAGS. If HOST_CFLAGS also exists, it is used.\n' printf ' CPPFLAGS C preprocessor flags. Default is "".\n' printf ' LDFLAGS Linker flags. Default is "".\n' printf ' PREFIX The prefix to install to. Default is "/usr/local".\n' printf ' If PREFIX is "/usr", install path will be "/usr/bin".\n' printf ' BINDIR The directory to install binaries in. Default is "$PREFIX/bin".\n' printf ' INCLUDEDIR The directory to install header files in. Default is\n' printf ' "$PREFIX/include".\n' printf ' LIBDIR The directory to install libraries in. Default is\n' printf ' "$PREFIX/lib".\n' printf ' DATAROOTDIR The root location for data files. Default is "$PREFIX/share".\n' printf ' DATADIR The location for data files. Default is "$DATAROOTDIR".\n' printf ' MANDIR The location to install manpages to. Default is "$DATADIR/man".\n' printf ' MAN1DIR The location to install Section 1 manpages to. Default is\n' printf ' "$MANDIR/man1".\n' printf ' MAN3DIR The location to install Section 3 manpages to. Default is\n' printf ' "$MANDIR/man3".\n' printf ' NLSPATH The location to install locale catalogs to. Must be an absolute\n' printf ' path (or contain one). This is treated the same as the POSIX\n' printf ' definition of $NLSPATH (see POSIX environment variables for\n' printf ' more information). Default is "/usr/share/locale/%%L/%%N".\n' + printf ' PC_PATH The location to install pkg-config files to. Must be an\n' + printf ' path or contain one. Default is the first path given by the\n' + printf ' output of `pkg-config --variable=pc_path pkg-config`.\n' printf ' EXECSUFFIX The suffix to append to the executable names, used to not\n' printf ' interfere with other installed bc executables. Default is "".\n' printf ' EXECPREFIX The prefix to append to the executable names, used to not\n' printf ' interfere with other installed bc executables. Default is "".\n' printf ' DESTDIR For package creation. Default is "". If it is empty when\n' printf ' `%s` is run, it can also be passed to `make install`\n' "$script" printf ' later as an environment variable. If both are specified,\n' printf ' the one given to `%s` takes precedence.\n' "$script" printf ' LONG_BIT The number of bits in a C `long` type. This is mostly for the\n' printf ' embedded space since this `bc` uses `long`s internally for\n' printf ' overflow checking. In C99, a `long` is required to be 32 bits.\n' printf ' For most normal desktop systems, setting this is unnecessary,\n' printf ' except that 32-bit platforms with 64-bit longs may want to set\n' printf ' it to `32`. Default is the default of `LONG_BIT` for the target\n' printf ' platform. Minimum allowed is `32`. It is a build time error if\n' printf ' the specified value of `LONG_BIT` is greater than the default\n' printf ' value of `LONG_BIT` for the target platform.\n' printf ' GEN_HOST Whether to use `gen/strgen.c`, instead of `gen/strgen.sh`, to\n' printf ' produce the C files that contain the help texts as well as the\n' printf ' math libraries. By default, `gen/strgen.c` is used, compiled by\n' printf ' "$HOSTCC" and run on the host machine. Using `gen/strgen.sh`\n' printf ' removes the need to compile and run an executable on the host\n' printf ' machine since `gen/strgen.sh` is a POSIX shell script. However,\n' printf ' `gen/lib2.bc` is perilously close to 4095 characters, the max\n' printf ' supported length of a string literal in C99 (and it could be\n' printf ' added to in the future), and `gen/strgen.sh` generates a string\n' printf ' literal instead of an array, as `gen/strgen.c` does. For most\n' printf ' production-ready compilers, this limit probably is not\n' printf ' enforced, but it could be. Both options are still available for\n' printf ' this reason. If you are sure your compiler does not have the\n' printf ' limit and do not want to compile and run a binary on the host\n' printf ' machine, set this variable to "0". Any other value, or a\n' printf ' non-existent value, will cause the build system to compile and\n' printf ' run `gen/strgen.c`. Default is "".\n' printf ' GEN_EMU Emulator to run string generator code under (leave empty if not\n' printf ' necessary). This is not necessary when using `gen/strgen.sh`.\n' printf ' Default is "".\n' printf '\n' printf 'WARNING: even though `configure.sh` supports both option types, short and\n' printf 'long, it does not support handling both at the same time. Use only one type.\n' printf '\n' printf 'Settings\n' printf '========\n' printf '\n' printf 'bc and dc have some settings that, while they cannot be removed by build time\n' printf 'options, can have their defaults changed at build time by packagers. Users are\n' printf 'also able to change each setting with environment variables.\n' printf '\n' printf 'The following is a table of settings, along with their default values and the\n' printf 'environment variables users can use to change them. (For the defaults, non-zero\n' printf 'means on, and zero means off.)\n' printf '\n' printf '| Setting | Description | Default | Env Variable |\n' printf '| =============== | ==================== | ============ | ==================== |\n' printf '| bc.banner | Whether to display | 0 | BC_BANNER |\n' printf '| | the bc version | | |\n' printf '| | banner when in | | |\n' printf '| | interactive mode. | | |\n' printf '| --------------- | -------------------- | ------------ | -------------------- |\n' printf '| bc.sigint_reset | Whether SIGINT will | 1 | BC_SIGINT_RESET |\n' printf '| | reset bc, instead of | | |\n' printf '| | exiting, when in | | |\n' printf '| | interactive mode. | | |\n' printf '| --------------- | -------------------- | ------------ | -------------------- |\n' printf '| dc.sigint_reset | Whether SIGINT will | 1 | DC_SIGINT_RESET |\n' printf '| | reset dc, instead of | | |\n' printf '| | exiting, when in | | |\n' printf '| | interactive mode. | | |\n' printf '| --------------- | -------------------- | ------------ | -------------------- |\n' printf '| bc.tty_mode | Whether TTY mode for | 1 | BC_TTY_MODE |\n' printf '| | bc should be on when | | |\n' printf '| | available. | | |\n' printf '| --------------- | -------------------- | ------------ | -------------------- |\n' printf '| dc.tty_mode | Whether TTY mode for | 0 | BC_TTY_MODE |\n' printf '| | dc should be on when | | |\n' printf '| | available. | | |\n' printf '| --------------- | -------------------- | ------------ | -------------------- |\n' printf '| bc.prompt | Whether the prompt | $BC_TTY_MODE | BC_PROMPT |\n' printf '| | for bc should be on | | |\n' printf '| | in tty mode. | | |\n' printf '| --------------- | -------------------- | ------------ | -------------------- |\n' printf '| dc.prompt | Whether the prompt | $DC_TTY_MODE | DC_PROMPT |\n' printf '| | for dc should be on | | |\n' printf '| | in tty mode. | | |\n' printf '| --------------- | -------------------- | ------------ | -------------------- |\n' + printf '| bc.expr_exit | Whether to exit bc | 1 | BC_EXPR_EXIT |\n' + printf '| | if an expression or | | |\n' + printf '| | expression file is | | |\n' + printf '| | given with the -e or | | |\n' + printf '| | -f options. | | |\n' + printf '| --------------- | -------------------- | ------------ | -------------------- |\n' + printf '| dc.expr_exit | Whether to exit dc | 1 | DC_EXPR_EXIT |\n' + printf '| | if an expression or | | |\n' + printf '| | expression file is | | |\n' + printf '| | given with the -e or | | |\n' + printf '| | -f options. | | |\n' + printf '| --------------- | -------------------- | ------------ | -------------------- |\n' printf '\n' printf 'These settings are not meant to be changed on a whim. They are meant to ensure\n' printf 'that this bc and dc will conform to the expectations of the user on each\n' printf 'platform.\n' exit "$_usage_val" } # Replaces a file extension in a filename. This is used mostly to turn filenames # like `src/num.c` into `src/num.o`. In other words, it helps to link targets to # the files they depend on. # # @param file The filename. # @param ext1 The extension to replace. # @param ext2 The new extension. replace_ext() { if [ "$#" -ne 3 ]; then err_exit "Invalid number of args to $0" fi _replace_ext_file="$1" _replace_ext_ext1="$2" _replace_ext_ext2="$3" _replace_ext_result="${_replace_ext_file%.$_replace_ext_ext1}.$_replace_ext_ext2" printf '%s\n' "$_replace_ext_result" } # Replaces a file extension in every filename given in a list. The list is just # a space-separated list of words, so filenames are expected to *not* have # spaces in them. See the documentation for `replace_ext()`. # # @param files The list of space-separated filenames to replace extensions for. # @param ext1 The extension to replace. # @param ext2 The new extension. replace_exts() { if [ "$#" -ne 3 ]; then err_exit "Invalid number of args to $0" fi _replace_exts_files="$1" _replace_exts_ext1="$2" _replace_exts_ext2="$3" for _replace_exts_file in $_replace_exts_files; do _replace_exts_new_name=$(replace_ext "$_replace_exts_file" "$_replace_exts_ext1" "$_replace_exts_ext2") _replace_exts_result="$_replace_exts_result $_replace_exts_new_name" done printf '%s\n' "$_replace_exts_result" } # Finds a placeholder in @a str and replaces it. This is the workhorse of # configure.sh. It's what replaces placeholders in Makefile.in with the data # needed for the chosen build. Below, you will see a lot of calls to this # function. # # Note that needle can never contain an exclamation point. For more information, # see substring_replace() in scripts/functions.sh. # # @param str The string to find and replace placeholders in. # @param needle The placeholder name. # @param replacement The string to use to replace the placeholder. replace() { if [ "$#" -ne 3 ]; then err_exit "Invalid number of args to $0" fi _replace_str="$1" _replace_needle="$2" _replace_replacement="$3" substring_replace "$_replace_str" "%%$_replace_needle%%" "$_replace_replacement" } # This function finds all the source files that need to be built. If there is # only one argument and it is empty, then all source files are built. Otherwise, # the arguments are all assumed to be source files that should *not* be built. find_src_files() { + _find_src_files_args="" + if [ "$#" -ge 1 ] && [ "$1" != "" ]; then while [ "$#" -ge 1 ]; do _find_src_files_a="${1## }" shift - _find_src_files_args="$_find_src_files_args ! -path src/${_find_src_files_a}" + _find_src_files_args=$(printf '%s\n%s/src/%s\n' "$_find_src_files_args" "$scriptdir" "${_find_src_files_a}") done - else - _find_src_files_args="-print" fi - printf '%s\n' $(find src/ -depth -name "*.c" $_find_src_files_args) + _find_src_files_files=$(find "$scriptdir/src/" -depth -name "*.c" -print) + + _find_src_files_result="" + + for _find_src_files_f in $_find_src_files_files; do + + # If this is true, the file is part of args, and therefore, unneeded. + if [ "${_find_src_files_args##*$_find_src_files_f}" != "${_find_src_files_args}" ]; then + continue + fi + + _find_src_files_result=$(printf '%s\n%s\n' "$_find_src_files_result" "$_find_src_files_f") + + done + + printf '%s\n' "$_find_src_files_result" } # This function generates a list of files to go into the Makefile. It generates # the list of object files, as well as the list of test coverage files. # # @param contents The contents of the Makefile template to put the list of # files into. gen_file_list() { if [ "$#" -lt 1 ]; then err_exit "Invalid number of args to $0" fi _gen_file_list_contents="$1" shift - p=$(pwd) - - cd "$scriptdir" - if [ "$#" -ge 1 ]; then _gen_file_list_unneeded="$@" else _gen_file_list_unneeded="" fi _gen_file_list_needle_src="SRC" _gen_file_list_needle_obj="OBJ" _gen_file_list_needle_gcda="GCDA" _gen_file_list_needle_gcno="GCNO" _gen_file_list_replacement=$(find_src_files $_gen_file_list_unneeded | tr '\n' ' ') _gen_file_list_contents=$(replace "$_gen_file_list_contents" \ "$_gen_file_list_needle_src" "$_gen_file_list_replacement") - _gen_file_list_replacement=$(replace_exts "$_gen_file_list_replacement" "c" "o") + _gen_file_list_cbases="" + + for _gen_file_list_f in $_gen_file_list_replacement; do + _gen_file_list_b=$(basename "$_gen_file_list_f") + _gen_file_list_cbases="$_gen_file_list_cbases src/$_gen_file_list_b" + done + + _gen_file_list_replacement=$(replace_exts "$_gen_file_list_cbases" "c" "o") _gen_file_list_contents=$(replace "$_gen_file_list_contents" \ "$_gen_file_list_needle_obj" "$_gen_file_list_replacement") _gen_file_list_replacement=$(replace_exts "$_gen_file_list_replacement" "o" "gcda") _gen_file_list_contents=$(replace "$_gen_file_list_contents" \ "$_gen_file_list_needle_gcda" "$_gen_file_list_replacement") _gen_file_list_replacement=$(replace_exts "$_gen_file_list_replacement" "gcda" "gcno") _gen_file_list_contents=$(replace "$_gen_file_list_contents" \ "$_gen_file_list_needle_gcno" "$_gen_file_list_replacement") - cd "$p" - printf '%s\n' "$_gen_file_list_contents" } # Generates the proper test targets for each test to have its own target. This # allows `make test` to run in parallel. # # @param name Which calculator to generate tests for. # @param extra_math An integer that, if non-zero, activates extra math tests. # @param time_tests An integer that, if non-zero, tells the test suite to time # the execution of each test. gen_std_tests() { _gen_std_tests_name="$1" shift _gen_std_tests_extra_math="$1" shift _gen_std_tests_time_tests="$1" shift _gen_std_tests_extra_required=$(cat "$scriptdir/tests/extra_required.txt") for _gen_std_tests_t in $(cat "$scriptdir/tests/$_gen_std_tests_name/all.txt"); do if [ "$_gen_std_tests_extra_math" -eq 0 ]; then if [ -z "${_gen_std_tests_extra_required##*$_gen_std_tests_t*}" ]; then printf 'test_%s_%s:\n\t@printf "Skipping %s %s\\n"\n\n' \ "$_gen_std_tests_name" "$_gen_std_tests_t" "$_gen_std_tests_name" \ - "$_gen_std_tests_t" >> "$scriptdir/Makefile" + "$_gen_std_tests_t" >> "Makefile" continue fi fi - printf 'test_%s_%s:\n\t@sh tests/test.sh %s %s %s %s %s\n\n' \ - "$_gen_std_tests_name" "$_gen_std_tests_t" "$_gen_std_tests_name" \ + printf 'test_%s_%s:\n\t@export BC_TEST_OUTPUT_DIR="%s/tests"; sh \$(TESTSDIR)/test.sh %s %s %s %s %s\n\n' \ + "$_gen_std_tests_name" "$_gen_std_tests_t" "$builddir" "$_gen_std_tests_name" \ "$_gen_std_tests_t" "$generate_tests" "$time_tests" \ - "$*" >> "$scriptdir/Makefile" + "$*" >> "Makefile" done } # Generates a list of test targets that will be used as prerequisites for other # targets. # # @param name The name of the calculator to generate test targets for. gen_std_test_targets() { _gen_std_test_targets_name="$1" shift _gen_std_test_targets_tests=$(cat "$scriptdir/tests/${_gen_std_test_targets_name}/all.txt") for _gen_std_test_targets_t in $_gen_std_test_targets_tests; do printf ' test_%s_%s' "$_gen_std_test_targets_name" "$_gen_std_test_targets_t" done printf '\n' } # Generates the proper test targets for each error test to have its own target. # This allows `make test_bc_errors` and `make test_dc_errors` to run in # parallel. # # @param name Which calculator to generate tests for. gen_err_tests() { _gen_err_tests_name="$1" shift _gen_err_tests_fs=$(ls "$scriptdir/tests/$_gen_err_tests_name/errors/") for _gen_err_tests_t in $_gen_err_tests_fs; do - printf 'test_%s_error_%s:\n\t@sh tests/error.sh %s %s %s\n\n' \ - "$_gen_err_tests_name" "$_gen_err_tests_t" "$_gen_err_tests_name" \ - "$_gen_err_tests_t" "$*" >> "$scriptdir/Makefile" + printf 'test_%s_error_%s:\n\t@export BC_TEST_OUTPUT_DIR="%s/tests"; sh \$(TESTSDIR)/error.sh %s %s %s\n\n' \ + "$_gen_err_tests_name" "$_gen_err_tests_t" "$builddir" "$_gen_err_tests_name" \ + "$_gen_err_tests_t" "$*" >> "Makefile" done } # Generates a list of error test targets that will be used as prerequisites for # other targets. # # @param name The name of the calculator to generate test targets for. gen_err_test_targets() { _gen_err_test_targets_name="$1" shift _gen_err_test_targets_tests=$(ls "$scriptdir/tests/$_gen_err_test_targets_name/errors/") for _gen_err_test_targets_t in $_gen_err_test_targets_tests; do printf ' test_%s_error_%s' "$_gen_err_test_targets_name" "$_gen_err_test_targets_t" done printf '\n' } # Generates the proper script test targets for each script test to have its own # target. This allows `make test` to run in parallel. # # @param name Which calculator to generate tests for. # @param extra_math An integer that, if non-zero, activates extra math tests. # @param generate An integer that, if non-zero, activates generated tests. # @param time_tests An integer that, if non-zero, tells the test suite to time # the execution of each test. gen_script_tests() { _gen_script_tests_name="$1" shift _gen_script_tests_extra_math="$1" shift _gen_script_tests_generate="$1" shift _gen_script_tests_time="$1" shift _gen_script_tests_tests=$(cat "$scriptdir/tests/$_gen_script_tests_name/scripts/all.txt") for _gen_script_tests_f in $_gen_script_tests_tests; do _gen_script_tests_b=$(basename "$_gen_script_tests_f" ".${_gen_script_tests_name}") - printf 'test_%s_script_%s:\n\t@sh tests/script.sh %s %s %s 1 %s %s %s\n\n' \ - "$_gen_script_tests_name" "$_gen_script_tests_b" "$_gen_script_tests_name" \ + printf 'test_%s_script_%s:\n\t@export BC_TEST_OUTPUT_DIR="%s/tests"; sh \$(TESTSDIR)/script.sh %s %s %s 1 %s %s %s\n\n' \ + "$_gen_script_tests_name" "$_gen_script_tests_b" "$builddir" "$_gen_script_tests_name" \ "$_gen_script_tests_f" "$_gen_script_tests_extra_math" "$_gen_script_tests_generate" \ - "$_gen_script_tests_time" "$*" >> "$scriptdir/Makefile" + "$_gen_script_tests_time" "$*" >> "Makefile" done } set_default() { _set_default_on="$1" shift _set_default_name="$1" shift # The reason that the variables that are being set do not have the same # non-collision avoidance that the other variables do is that we *do* want # the settings of these variables to leak out of the function. They adjust # the settings outside of the function. case "$_set_default_name" in bc.banner) bc_default_banner="$_set_default_on" ;; bc.sigint_reset) bc_default_sigint_reset="$_set_default_on" ;; dc.sigint_reset) dc_default_sigint_reset="$_set_default_on" ;; bc.tty_mode) bc_default_tty_mode="$_set_default_on" ;; dc.tty_mode) dc_default_tty_mode="$_set_default_on" ;; bc.prompt) bc_default_prompt="$_set_default_on" ;; dc.prompt) dc_default_prompt="$_set_default_on" ;; + bc.expr_exit) bc_default_expr_exit="$_set_default_on";; + dc.expr_exit) dc_default_expr_exit="$_set_default_on";; ?) usage "Invalid setting: $_set_default_name" ;; esac } # Generates a list of script test targets that will be used as prerequisites for # other targets. # # @param name The name of the calculator to generate script test targets for. gen_script_test_targets() { _gen_script_test_targets_name="$1" shift _gen_script_test_targets_tests=$(cat "$scriptdir/tests/$_gen_script_test_targets_name/scripts/all.txt") for _gen_script_test_targets_f in $_gen_script_test_targets_tests; do _gen_script_test_targets_b=$(basename "$_gen_script_test_targets_f" \ ".$_gen_script_test_targets_name") printf ' test_%s_script_%s' "$_gen_script_test_targets_name" \ "$_gen_script_test_targets_b" done printf '\n' } # This is a list of defaults, but it is also the list of possible options for # users to change. # # The development options are: force (force options even if they fail), valgrind # (build in a way suitable for valgrind testing), memcheck (same as valgrind), # and fuzzing (build in a way suitable for fuzzing). bc_only=0 dc_only=0 coverage=0 karatsuba_len=32 debug=0 hist=1 extra_math=1 optimization="" generate_tests=1 install_manpages=1 nls=1 force=0 strip_bin=1 all_locales=0 library=0 fuzz=0 time_tests=0 vg=0 memcheck=0 clean=1 # The empty strings are because they depend on TTY mode. If they are directly # set, though, they will be integers. We test for empty strings later. bc_default_banner=0 bc_default_sigint_reset=1 dc_default_sigint_reset=1 bc_default_tty_mode=1 dc_default_tty_mode=0 bc_default_prompt="" dc_default_prompt="" +bc_default_expr_exit=1 +dc_default_expr_exit=1 # getopts is a POSIX utility, but it cannot handle long options. Thus, the # handling of long options is done by hand, and that's the reason that short and # long options cannot be mixed. while getopts "abBcdDEfgGhHk:lMmNO:S:s:tTvz-" opt; do case "$opt" in a) library=1 ;; b) bc_only=1 ;; B) dc_only=1 ;; c) coverage=1 ;; C) clean=0 ;; d) dc_only=1 ;; D) bc_only=1 ;; E) extra_math=0 ;; f) force=1 ;; g) debug=1 ;; G) generate_tests=0 ;; h) usage ;; H) hist=0 ;; k) karatsuba_len="$OPTARG" ;; l) all_locales=1 ;; m) memcheck=1 ;; M) install_manpages=0 ;; N) nls=0 ;; O) optimization="$OPTARG" ;; S) set_default 0 "$OPTARG" ;; s) set_default 1 "$OPTARG" ;; t) time_tests=1 ;; T) strip_bin=0 ;; v) vg=1 ;; z) fuzz=1 ;; -) arg="$1" arg="${arg#--}" LONG_OPTARG="${arg#*=}" case $arg in help) usage ;; library) library=1 ;; bc-only) bc_only=1 ;; dc-only) dc_only=1 ;; coverage) coverage=1 ;; debug) debug=1 ;; force) force=1 ;; prefix=?*) PREFIX="$LONG_OPTARG" ;; prefix) if [ "$#" -lt 2 ]; then usage "No argument given for '--$arg' option" fi PREFIX="$2" shift ;; bindir=?*) BINDIR="$LONG_OPTARG" ;; bindir) if [ "$#" -lt 2 ]; then usage "No argument given for '--$arg' option" fi BINDIR="$2" shift ;; includedir=?*) INCLUDEDIR="$LONG_OPTARG" ;; includedir) if [ "$#" -lt 2 ]; then usage "No argument given for '--$arg' option" fi INCLUDEDIR="$2" shift ;; libdir=?*) LIBDIR="$LONG_OPTARG" ;; libdir) if [ "$#" -lt 2 ]; then usage "No argument given for '--$arg' option" fi LIBDIR="$2" shift ;; datarootdir=?*) DATAROOTDIR="$LONG_OPTARG" ;; datarootdir) if [ "$#" -lt 2 ]; then usage "No argument given for '--$arg' option" fi DATAROOTDIR="$2" shift ;; datadir=?*) DATADIR="$LONG_OPTARG" ;; datadir) if [ "$#" -lt 2 ]; then usage "No argument given for '--$arg' option" fi DATADIR="$2" shift ;; mandir=?*) MANDIR="$LONG_OPTARG" ;; mandir) if [ "$#" -lt 2 ]; then usage "No argument given for '--$arg' option" fi MANDIR="$2" shift ;; man1dir=?*) MAN1DIR="$LONG_OPTARG" ;; man1dir) if [ "$#" -lt 2 ]; then usage "No argument given for '--$arg' option" fi MAN1DIR="$2" shift ;; man3dir=?*) MAN3DIR="$LONG_OPTARG" ;; man3dir) if [ "$#" -lt 2 ]; then usage "No argument given for '--$arg' option" fi MAN3DIR="$2" shift ;; localedir=?*) LOCALEDIR="$LONG_OPTARG" ;; localedir) if [ "$#" -lt 2 ]; then usage "No argument given for '--$arg' option" fi LOCALEDIR="$2" shift ;; karatsuba-len=?*) karatsuba_len="$LONG_OPTARG" ;; karatsuba-len) if [ "$#" -lt 2 ]; then usage "No argument given for '--$arg' option" fi karatsuba_len="$1" shift ;; opt=?*) optimization="$LONG_OPTARG" ;; opt) if [ "$#" -lt 2 ]; then usage "No argument given for '--$arg' option" fi optimization="$1" shift ;; set-default-on=?*) set_default 1 "$LONG_OPTARG" ;; set-default-on) if [ "$#" -lt 2 ]; then usage "No argument given for '--$arg' option" fi set_default 1 "$1" shift ;; set-default-off=?*) set_default 0 "$LONG_OPTARG" ;; set-default-off) if [ "$#" -lt 2 ]; then usage "No argument given for '--$arg' option" fi set_default 0 "$1" shift ;; disable-bc) dc_only=1 ;; disable-dc) bc_only=1 ;; disable-clean) clean=0 ;; disable-extra-math) extra_math=0 ;; disable-generated-tests) generate_tests=0 ;; disable-history) hist=0 ;; disable-man-pages) install_manpages=0 ;; disable-nls) nls=0 ;; disable-strip) strip_bin=0 ;; enable-test-timing) time_tests=1 ;; enable-valgrind) vg=1 ;; enable-fuzz-mode) fuzz=1 ;; enable-memcheck) memcheck=1 ;; install-all-locales) all_locales=1 ;; help* | bc-only* | dc-only* | coverage* | debug*) usage "No arg allowed for --$arg option" ;; disable-bc* | disable-dc* | disable-clean*) usage "No arg allowed for --$arg option" ;; disable-extra-math*) usage "No arg allowed for --$arg option" ;; disable-generated-tests* | disable-history*) usage "No arg allowed for --$arg option" ;; disable-man-pages* | disable-nls* | disable-strip*) usage "No arg allowed for --$arg option" ;; enable-fuzz-mode* | enable-test-timing* | enable-valgrind*) usage "No arg allowed for --$arg option" ;; enable-memcheck* | install-all-locales*) usage "No arg allowed for --$arg option" ;; '') break ;; # "--" terminates argument processing * ) usage "Invalid option $LONG_OPTARG" ;; esac shift OPTIND=1 ;; ?) usage "Invalid option: $opt" ;; esac done # Sometimes, developers don't want configure.sh to do a config clean. But # sometimes they do. if [ "$clean" -ne 0 ]; then if [ -f ./Makefile ]; then make clean_config > /dev/null fi fi # It is an error to say that bc only should be built and likewise for dc. if [ "$bc_only" -eq 1 ] && [ "$dc_only" -eq 1 ]; then usage "Can only specify one of -b(-D) or -d(-B)" fi # The library is mutually exclusive to the calculators, so it's an error to # give an option for either of them. if [ "$library" -ne 0 ]; then if [ "$bc_only" -eq 1 ] || [ "$dc_only" -eq 1 ]; then usage "Must not specify -b(-D) or -d(-B) when building the library" fi fi # KARATSUBA_LEN must be an integer and must be 16 or greater. case $karatsuba_len in (*[!0-9]*|'') usage "KARATSUBA_LEN is not a number" ;; (*) ;; esac if [ "$karatsuba_len" -lt 16 ]; then usage "KARATSUBA_LEN is less than 16" fi set -e if [ -z "${LONG_BIT+set}" ]; then LONG_BIT_DEFINE="" elif [ "$LONG_BIT" -lt 32 ]; then usage "LONG_BIT is less than 32" else LONG_BIT_DEFINE="-DBC_LONG_BIT=\$(BC_LONG_BIT)" fi if [ -z "$CC" ]; then CC="c99" else # I had users complain that, if they gave CFLAGS as part of CC, which # autotools allows in its braindead way, the build would fail with an error. # I don't like adjusting for autotools, but oh well. These lines puts the # stuff after the first space into CFLAGS. ccbase=$(basename "$CC") suffix=" *" prefix="* " if [ "${ccbase%%$suffix}" != "$ccbase" ]; then ccflags="${ccbase#$prefix}" cc="${ccbase%%$suffix}" ccdir=$(dirname "$CC") if [ "$ccdir" = "." ] && [ "${CC#.}" = "$CC" ]; then ccdir="" else ccdir="$ccdir/" fi CC="${ccdir}${cc}" CFLAGS="$CFLAGS $ccflags" fi fi if [ -z "$HOSTCC" ] && [ -z "$HOST_CC" ]; then HOSTCC="$CC" elif [ -z "$HOSTCC" ]; then HOSTCC="$HOST_CC" fi if [ "$HOSTCC" != "$CC" ]; then # Like above, this splits HOSTCC and HOSTCFLAGS. ccbase=$(basename "$HOSTCC") suffix=" *" prefix="* " if [ "${ccbase%%$suffix}" != "$ccbase" ]; then ccflags="${ccbase#$prefix}" cc="${ccbase%%$suffix}" ccdir=$(dirname "$HOSTCC") if [ "$ccdir" = "." ] && [ "${HOSTCC#.}" = "$HOSTCC" ]; then ccdir="" else ccdir="$ccdir/" fi HOSTCC="${ccdir}${cc}" HOSTCFLAGS="$HOSTCFLAGS $ccflags" fi fi if [ -z "${HOSTCFLAGS+set}" ] && [ -z "${HOST_CFLAGS+set}" ]; then HOSTCFLAGS="$CFLAGS" elif [ -z "${HOSTCFLAGS+set}" ]; then HOSTCFLAGS="$HOST_CFLAGS" fi # Store these for the cross compilation detection later. OLDCFLAGS="$CFLAGS" OLDHOSTCFLAGS="$HOSTCFLAGS" link="@printf 'No link necessary\\\\n'" main_exec="BC" executable="BC_EXEC" tests="test_bc timeconst test_dc" -bc_test="@tests/all.sh bc $extra_math 1 $generate_tests $time_tests \$(BC_EXEC)" -bc_test_np="@tests/all.sh -n bc $extra_math 1 $generate_tests $time_tests \$(BC_EXEC)" -dc_test="@tests/all.sh dc $extra_math 1 $generate_tests $time_tests \$(DC_EXEC)" -dc_test_np="@tests/all.sh -n dc $extra_math 1 $generate_tests $time_tests \$(DC_EXEC)" +bc_test="@export BC_TEST_OUTPUT_DIR=\"$builddir/tests\"; \$(TESTSDIR)/all.sh bc $extra_math 1 $generate_tests $time_tests \$(BC_EXEC)" +bc_test_np="@export BC_TEST_OUTPUT_DIR=\"$builddir/tests\"; \$(TESTSDIR)/all.sh -n bc $extra_math 1 $generate_tests $time_tests \$(BC_EXEC)" +dc_test="@export BC_TEST_OUTPUT_DIR=\"$builddir/tests\"; \$(TESTSDIR)/all.sh dc $extra_math 1 $generate_tests $time_tests \$(DC_EXEC)" +dc_test_np="@export BC_TEST_OUTPUT_DIR=\"$builddir/tests\"; \$(TESTSDIR)/all.sh -n dc $extra_math 1 $generate_tests $time_tests \$(DC_EXEC)" -timeconst="@tests/bc/timeconst.sh tests/bc/scripts/timeconst.bc \$(BC_EXEC)" +timeconst="@export BC_TEST_OUTPUT_DIR=\"$builddir/tests\"; \$(TESTSDIR)/bc/timeconst.sh \$(TESTSDIR)/bc/scripts/timeconst.bc \$(BC_EXEC)" # In order to have cleanup at exit, we need to be in # debug mode, so don't run valgrind without that. if [ "$vg" -ne 0 ]; then debug=1 bc_test_exec='valgrind $(VALGRIND_ARGS) $(BC_EXEC)' dc_test_exec='valgrind $(VALGRIND_ARGS) $(DC_EXEC)' else bc_test_exec='$(BC_EXEC)' dc_test_exec='$(DC_EXEC)' fi test_bc_history_prereqs="test_bc_history_all" test_dc_history_prereqs="test_dc_history_all" karatsuba="@printf 'karatsuba cannot be run because one of bc or dc is not built\\\\n'" karatsuba_test="@printf 'karatsuba cannot be run because one of bc or dc is not built\\\\n'" bc_lib="\$(GEN_DIR)/lib.o" bc_help="\$(GEN_DIR)/bc_help.o" dc_help="\$(GEN_DIR)/dc_help.o" default_target_prereqs="\$(BIN) \$(OBJS)" default_target_cmd="\$(CC) \$(CFLAGS) \$(OBJS) \$(LDFLAGS) -o \$(EXEC)" default_target="\$(DC_EXEC)" second_target_prereqs="" second_target_cmd="$default_target_cmd" second_target="\$(BC_EXEC)" # This if/else if chain is for setting the defaults that change based on whether # the library is being built, bc only, dc only, or both calculators. if [ "$library" -ne 0 ]; then extra_math=1 nls=0 hist=0 bc=1 dc=1 default_target_prereqs="\$(BIN) \$(OBJ)" default_target_cmd="ar -r -cu \$(LIBBC) \$(OBJ)" default_target="\$(LIBBC)" tests="test_library" test_bc_history_prereqs=" test_bc_history_skip" test_dc_history_prereqs=" test_dc_history_skip" + install_prereqs=" install_library" + uninstall_prereqs=" uninstall_library" + install_man_prereqs=" install_bcl_manpage" + uninstall_man_prereqs=" uninstall_bcl_manpage" + elif [ "$bc_only" -eq 1 ]; then bc=1 dc=0 dc_help="" executables="bc" dc_test="@printf 'No dc tests to run\\\\n'" dc_test_np="@printf 'No dc tests to run\\\\n'" test_dc_history_prereqs=" test_dc_history_skip" install_prereqs=" install_execs" install_man_prereqs=" install_bc_manpage" uninstall_prereqs=" uninstall_bc" uninstall_man_prereqs=" uninstall_bc_manpage" default_target="\$(BC_EXEC)" second_target="\$(DC_EXEC)" tests="test_bc timeconst" elif [ "$dc_only" -eq 1 ]; then bc=0 dc=1 bc_lib="" bc_help="" executables="dc" main_exec="DC" executable="DC_EXEC" bc_test="@printf 'No bc tests to run\\\\n'" bc_test_np="@printf 'No bc tests to run\\\\n'" test_bc_history_prereqs=" test_bc_history_skip" timeconst="@printf 'timeconst cannot be run because bc is not built\\\\n'" install_prereqs=" install_execs" install_man_prereqs=" install_dc_manpage" uninstall_prereqs=" uninstall_dc" uninstall_man_prereqs=" uninstall_dc_manpage" tests="test_dc" else bc=1 dc=1 executables="bc and dc" karatsuba="@\$(KARATSUBA) 30 0 \$(BC_EXEC)" karatsuba_test="@\$(KARATSUBA) 1 100 \$(BC_EXEC)" if [ "$library" -eq 0 ]; then install_prereqs=" install_execs" install_man_prereqs=" install_bc_manpage install_dc_manpage" uninstall_prereqs=" uninstall_bc uninstall_dc" uninstall_man_prereqs=" uninstall_bc_manpage uninstall_dc_manpage" else install_prereqs=" install_library install_bcl_header" install_man_prereqs=" install_bcl_manpage" uninstall_prereqs=" uninstall_library uninstall_bcl_header" uninstall_man_prereqs=" uninstall_bcl_manpage" tests="test_library" fi second_target_prereqs="$default_target_prereqs" default_target_prereqs="$second_target" default_target_cmd="\$(LINK) \$(BIN) \$(EXEC_PREFIX)\$(DC)" fi # We need specific stuff for fuzzing. if [ "$fuzz" -ne 0 ]; then debug=1 hist=0 nls=0 optimization="3" fi # This sets some necessary things for debug mode. if [ "$debug" -eq 1 ]; then if [ -z "$CFLAGS" ] && [ -z "$optimization" ]; then CFLAGS="-O0" fi CFLAGS="-g $CFLAGS" else CPPFLAGS="-DNDEBUG $CPPFLAGS" if [ "$strip_bin" -ne 0 ]; then LDFLAGS="-s $LDFLAGS" fi fi # Set optimization CFLAGS. if [ -n "$optimization" ]; then CFLAGS="-O$optimization $CFLAGS" fi # Set test coverage defaults. if [ "$coverage" -eq 1 ]; then if [ "$bc_only" -eq 1 ] || [ "$dc_only" -eq 1 ]; then usage "Can only specify -c without -b or -d" fi CFLAGS="-fprofile-arcs -ftest-coverage -g -O0 $CFLAGS" CPPFLAGS="-DNDEBUG $CPPFLAGS" COVERAGE_OUTPUT="@gcov -pabcdf \$(GCDA) \$(BC_GCDA) \$(DC_GCDA) \$(HISTORY_GCDA) \$(RAND_GCDA)" COVERAGE_OUTPUT="$COVERAGE_OUTPUT;\$(RM) -f \$(GEN)*.gc*" COVERAGE_OUTPUT="$COVERAGE_OUTPUT;gcovr --exclude-unreachable-branches --exclude-throw-branches --html-details --output index.html" COVERAGE_PREREQS=" test coverage_output" else COVERAGE_OUTPUT="@printf 'Coverage not generated\\\\n'" COVERAGE_PREREQS="" fi # Set some defaults. if [ -z "${DESTDIR+set}" ]; then destdir="" else destdir="DESTDIR = $DESTDIR" fi if [ -z "${PREFIX+set}" ]; then PREFIX="/usr/local" fi if [ -z "${BINDIR+set}" ]; then BINDIR="$PREFIX/bin" fi if [ -z "${INCLUDEDIR+set}" ]; then INCLUDEDIR="$PREFIX/include" fi if [ -z "${LIBDIR+set}" ]; then LIBDIR="$PREFIX/lib" fi +if [ -z "${PC_PATH+set}" ]; then + + set +e + + command -v pkg-config > /dev/null + err=$? + + set -e + + if [ "$err" -eq 0 ]; then + PC_PATH=$(pkg-config --variable=pc_path pkg-config) + PC_PATH="${PC_PATH%%:*}" + else + PC_PATH="" + fi + +fi + # Set a default for the DATAROOTDIR. This is done if either manpages will be # installed, or locales are enabled because that's probably where NLS_PATH # points. if [ "$install_manpages" -ne 0 ] || [ "$nls" -ne 0 ]; then if [ -z "${DATAROOTDIR+set}" ]; then DATAROOTDIR="$PREFIX/share" fi fi # Set defaults for manpage environment variables. if [ "$install_manpages" -ne 0 ]; then if [ -z "${DATADIR+set}" ]; then DATADIR="$DATAROOTDIR" fi if [ -z "${MANDIR+set}" ]; then MANDIR="$DATADIR/man" fi if [ -z "${MAN1DIR+set}" ]; then MAN1DIR="$MANDIR/man1" fi if [ -z "${MAN3DIR+set}" ]; then MAN3DIR="$MANDIR/man3" fi else install_man_prereqs="" uninstall_man_prereqs="" fi # Here is where we test NLS (the locale system). This is done by trying to # compile src/vm.c, which has the relevant code. If it fails, then it is # disabled. if [ "$nls" -ne 0 ]; then set +e printf 'Testing NLS...\n' flags="-DBC_ENABLE_NLS=1 -DBC_ENABLED=$bc -DDC_ENABLED=$dc" flags="$flags -DBC_ENABLE_HISTORY=$hist -DBC_ENABLE_LIBRARY=0 -DBC_ENABLE_AFL=0" - flags="$flags -DBC_ENABLE_EXTRA_MATH=$extra_math -I./include/" + flags="$flags -DBC_ENABLE_EXTRA_MATH=$extra_math -I$scriptdir/include/" flags="$flags -D_POSIX_C_SOURCE=200809L -D_XOPEN_SOURCE=700" - "$CC" $CPPFLAGS $CFLAGS $flags -c "src/vm.c" -o "$scriptdir/vm.o" > /dev/null 2>&1 + "$CC" $CPPFLAGS $CFLAGS $flags -c "$scriptdir/src/vm.c" -o "./vm.o" > /dev/null 2>&1 err="$?" - rm -rf "$scriptdir/vm.o" + rm -rf "./vm.o" # If this errors, it is probably because of building on Windows, # and NLS is not supported on Windows, so disable it. if [ "$err" -ne 0 ]; then printf 'NLS does not work.\n' if [ $force -eq 0 ]; then printf 'Disabling NLS...\n\n' nls=0 else printf 'Forcing NLS...\n\n' fi else printf 'NLS works.\n\n' printf 'Testing gencat...\n' - gencat "$scriptdir/en_US.cat" "$scriptdir/locales/en_US.msg" > /dev/null 2>&1 + gencat "./en_US.cat" "$scriptdir/locales/en_US.msg" > /dev/null 2>&1 err="$?" - rm -rf "$scriptdir/en_US.cat" + rm -rf "./en_US.cat" if [ "$err" -ne 0 ]; then printf 'gencat does not work.\n' if [ $force -eq 0 ]; then printf 'Disabling NLS...\n\n' nls=0 else printf 'Forcing NLS...\n\n' fi else printf 'gencat works.\n\n' # It turns out that POSIX locales are really terrible, and running # gencat on one machine is not guaranteed to make those cat files # portable to another machine, so we had better warn the user here. if [ "$HOSTCC" != "$CC" ] || [ "$OLDHOSTCFLAGS" != "$OLDCFLAGS" ]; then printf 'Cross-compile detected.\n\n' printf 'WARNING: Catalog files generated with gencat may not be portable\n' printf ' across different architectures.\n\n' fi if [ -z "$NLSPATH" ]; then NLSPATH="/usr/share/locale/%L/%N" fi install_locales_prereqs=" install_locales" uninstall_locales_prereqs=" uninstall_locales" fi fi set -e else install_locales_prereqs="" uninstall_locales_prereqs="" all_locales=0 fi if [ "$nls" -ne 0 ] && [ "$all_locales" -ne 0 ]; then install_locales="\$(LOCALE_INSTALL) -l \$(NLSPATH) \$(MAIN_EXEC) \$(DESTDIR)" else install_locales="\$(LOCALE_INSTALL) \$(NLSPATH) \$(MAIN_EXEC) \$(DESTDIR)" fi # Like the above tested locale support, this tests history. if [ "$hist" -eq 1 ]; then set +e printf 'Testing history...\n' flags="-DBC_ENABLE_HISTORY=1 -DBC_ENABLED=$bc -DDC_ENABLED=$dc" flags="$flags -DBC_ENABLE_NLS=$nls -DBC_ENABLE_LIBRARY=0 -DBC_ENABLE_AFL=0" - flags="$flags -DBC_ENABLE_EXTRA_MATH=$extra_math -I./include/" + flags="$flags -DBC_ENABLE_EXTRA_MATH=$extra_math -I$scriptdir/include/" flags="$flags -D_POSIX_C_SOURCE=200809L -D_XOPEN_SOURCE=700" - "$CC" $CPPFLAGS $CFLAGS $flags -c "src/history.c" -o "$scriptdir/history.o" > /dev/null 2>&1 + "$CC" $CPPFLAGS $CFLAGS $flags -c "$scriptdir/src/history.c" -o "./history.o" > /dev/null 2>&1 err="$?" - rm -rf "$scriptdir/history.o" + rm -rf "./history.o" # If this errors, it is probably because of building on Windows, # and history is not supported on Windows, so disable it. if [ "$err" -ne 0 ]; then printf 'History does not work.\n' if [ $force -eq 0 ]; then printf 'Disabling history...\n\n' hist=0 else printf 'Forcing history...\n\n' fi else printf 'History works.\n\n' fi set -e fi # We have to disable the history tests if it is disabled or valgrind is on. if [ "$hist" -eq 0 ] || [ "$vg" -ne 0 ]; then test_bc_history_prereqs=" test_bc_history_skip" test_dc_history_prereqs=" test_dc_history_skip" history_tests="@printf 'Skipping history tests...\\\\n'" else - history_tests="@printf '\$(TEST_STARS)\\\\n\\\\nRunning history tests...\\\\n\\\\n' \&\& tests/history.sh bc -a \&\& tests/history.sh dc -a \&\& printf '\\\\nAll history tests passed.\\\\n\\\\n\$(TEST_STARS)\\\\n'" + history_tests="@printf '\$(TEST_STARS)\\\\n\\\\nRunning history tests...\\\\n\\\\n' \&\& \$(TESTSDIR)/history.sh bc -a \&\& \$(TESTSDIR)/history.sh dc -a \&\& printf '\\\\nAll history tests passed.\\\\n\\\\n\$(TEST_STARS)\\\\n'" fi # Test OpenBSD. This is not in an if statement because regardless of whatever # the user says, we need to know if we are on OpenBSD to activate _BSD_SOURCE. # No, I cannot `#define _BSD_SOURCE` in a header because OpenBSD's patched GCC # and Clang complain that that is only allowed for system headers. Sigh....So we # have to check at configure time and set it on the compiler command-line. And # we have to set it because we also set _POSIX_C_SOURCE, which OpenBSD headers # detect, and when they detect it, they turn off _BSD_SOURCE unless it is # specifically requested. set +e printf 'Testing for OpenBSD...\n' flags="-DBC_TEST_OPENBSD -DBC_ENABLE_AFL=0" -"$CC" $CPPFLAGS $CFLAGS $flags -I./include -E "include/status.h" > /dev/null 2>&1 +"$CC" $CPPFLAGS $CFLAGS $flags "-I$scriptdir/include" -E "$scriptdir/include/status.h" > /dev/null 2>&1 err="$?" if [ "$err" -ne 0 ]; then printf 'On OpenBSD. Using _BSD_SOURCE.\n\n' bsd="-D_BSD_SOURCE" else printf 'Not on OpenBSD.\n\n' bsd="" fi if [ "$library" -eq 1 ]; then bc_lib="" fi if [ "$extra_math" -eq 1 ] && [ "$bc" -ne 0 ] && [ "$library" -eq 0 ]; then BC_LIB2_O="\$(GEN_DIR)/lib2.o" else BC_LIB2_O="" fi # These lines set the appropriate targets based on whether `gen/strgen.c` or # `gen/strgen.sh` is used. GEN="strgen" GEN_EXEC_TARGET="\$(HOSTCC) \$(HOSTCFLAGS) -o \$(GEN_EXEC) \$(GEN_C)" CLEAN_PREREQS=" clean_gen clean_coverage" if [ -z "${GEN_HOST+set}" ]; then GEN_HOST=1 else if [ "$GEN_HOST" -eq 0 ]; then GEN="strgen.sh" GEN_EXEC_TARGET="@printf 'Do not need to build gen/strgen.c\\\\n'" CLEAN_PREREQS=" clean_coverage" fi fi manpage_args="" unneeded="" headers="\$(HEADERS)" # This series of if statements figure out what source files are *not* needed. if [ "$extra_math" -eq 0 ]; then manpage_args="E" unneeded="$unneeded rand.c" else headers="$headers \$(EXTRA_MATH_HEADERS)" fi # All of these next if statements set the build type and mark certain source # files as unneeded so that they won't have targets generated for them. if [ "$hist" -eq 0 ]; then manpage_args="${manpage_args}H" unneeded="$unneeded history.c" else headers="$headers \$(HISTORY_HEADERS)" fi if [ "$nls" -eq 0 ]; then manpage_args="${manpage_args}N" fi if [ "$bc" -eq 0 ]; then unneeded="$unneeded bc.c bc_lex.c bc_parse.c" else headers="$headers \$(BC_HEADERS)" fi if [ "$dc" -eq 0 ]; then unneeded="$unneeded dc.c dc_lex.c dc_parse.c" else headers="$headers \$(DC_HEADERS)" fi +# This convoluted mess does pull the version out. If you change the format of +# include/version.h, you may have to change this line. +version=$(cat "$scriptdir/include/version.h" | grep "VERSION " - | awk '{ print $3 }' -) + if [ "$library" -ne 0 ]; then + unneeded="$unneeded args.c opt.c read.c file.c main.c" unneeded="$unneeded lang.c lex.c parse.c program.c" unneeded="$unneeded bc.c bc_lex.c bc_parse.c" unneeded="$unneeded dc.c dc_lex.c dc_parse.c" headers="$headers \$(LIBRARY_HEADERS)" + + if [ "$PC_PATH" != "" ]; then + + contents=$(cat "$scriptdir/bcl.pc.in") + + contents=$(replace "$contents" "INCLUDEDIR" "$INCLUDEDIR") + contents=$(replace "$contents" "LIBDIR" "$LIBDIR") + contents=$(replace "$contents" "VERSION" "$version") + + printf '%s\n' "$contents" > "./bcl.pc" + + pkg_config_install="\$(SAFE_INSTALL) \$(PC_INSTALL_ARGS) \"\$(BCL_PC)\" \"\$(DESTDIR)\$(PC_PATH)/\$(BCL_PC)\"" + pkg_config_uninstall="\$(RM) -f \"\$(DESTDIR)\$(PC_PATH)/\$(BCL_PC)\"" + + else + + pkg_config_install="" + pkg_config_uninstall="" + + fi + else + unneeded="$unneeded library.c" + + PC_PATH="" + pkg_config_install="" + pkg_config_uninstall="" + fi # library.c is not needed under normal circumstances. if [ "$unneeded" = "" ]; then unneeded="library.c" fi # This sets the appropriate manpage for a full build. if [ "$manpage_args" = "" ]; then manpage_args="A" fi if [ "$vg" -ne 0 ]; then memcheck=1 fi if [ "$bc_default_prompt" = "" ]; then bc_default_prompt="$bc_default_tty_mode" fi if [ "$dc_default_prompt" = "" ]; then dc_default_prompt="$dc_default_tty_mode" fi # Generate the test targets and prerequisites. bc_tests=$(gen_std_test_targets bc) bc_script_tests=$(gen_script_test_targets bc) bc_err_tests=$(gen_err_test_targets bc) dc_tests=$(gen_std_test_targets dc) dc_script_tests=$(gen_script_test_targets dc) dc_err_tests=$(gen_err_test_targets dc) # Print out the values; this is for debugging. +printf 'Version: %s\n' "$version" + if [ "$bc" -ne 0 ]; then printf 'Building bc\n' else printf 'Not building bc\n' fi if [ "$dc" -ne 0 ]; then printf 'Building dc\n' else printf 'Not building dc\n' fi printf '\n' printf 'BC_ENABLE_LIBRARY=%s\n\n' "$library" printf 'BC_ENABLE_HISTORY=%s\n' "$hist" printf 'BC_ENABLE_EXTRA_MATH=%s\n' "$extra_math" printf 'BC_ENABLE_NLS=%s\n' "$nls" printf 'BC_ENABLE_AFL=%s\n' "$fuzz" printf '\n' printf 'BC_NUM_KARATSUBA_LEN=%s\n' "$karatsuba_len" printf '\n' printf 'CC=%s\n' "$CC" printf 'CFLAGS=%s\n' "$CFLAGS" printf 'HOSTCC=%s\n' "$HOSTCC" printf 'HOSTCFLAGS=%s\n' "$HOSTCFLAGS" printf 'CPPFLAGS=%s\n' "$CPPFLAGS" printf 'LDFLAGS=%s\n' "$LDFLAGS" printf 'PREFIX=%s\n' "$PREFIX" printf 'BINDIR=%s\n' "$BINDIR" printf 'INCLUDEDIR=%s\n' "$INCLUDEDIR" printf 'LIBDIR=%s\n' "$LIBDIR" printf 'DATAROOTDIR=%s\n' "$DATAROOTDIR" printf 'DATADIR=%s\n' "$DATADIR" printf 'MANDIR=%s\n' "$MANDIR" printf 'MAN1DIR=%s\n' "$MAN1DIR" printf 'MAN3DIR=%s\n' "$MAN3DIR" printf 'NLSPATH=%s\n' "$NLSPATH" +printf 'PC_PATH=%s\n' "$PC_PATH" printf 'EXECSUFFIX=%s\n' "$EXECSUFFIX" printf 'EXECPREFIX=%s\n' "$EXECPREFIX" printf 'DESTDIR=%s\n' "$DESTDIR" printf 'LONG_BIT=%s\n' "$LONG_BIT" printf 'GEN_HOST=%s\n' "$GEN_HOST" printf 'GEN_EMU=%s\n' "$GEN_EMU" printf '\n' printf 'Setting Defaults\n' printf '================\n' printf 'bc.banner=%s\n' "$bc_default_banner" printf 'bc.sigint_reset=%s\n' "$bc_default_sigint_reset" printf 'dc.sigint_reset=%s\n' "$dc_default_sigint_reset" printf 'bc.tty_mode=%s\n' "$bc_default_tty_mode" printf 'dc.tty_mode=%s\n' "$dc_default_tty_mode" printf 'bc.prompt=%s\n' "$bc_default_prompt" printf 'dc.prompt=%s\n' "$dc_default_prompt" +printf 'bc.expr_exit=%s\n' "$bc_default_expr_exit" +printf 'dc.expr_exit=%s\n' "$dc_default_expr_exit" # This is where the real work begins. This is the point at which the Makefile.in # template is edited and output to the Makefile. contents=$(cat "$scriptdir/Makefile.in") needle="WARNING" replacement='*** WARNING: Autogenerated from Makefile.in. DO NOT MODIFY ***' contents=$(replace "$contents" "$needle" "$replacement") # The contents are edited to have the list of files to build. contents=$(gen_file_list "$contents" $unneeded) SRC_TARGETS="" # This line and loop generates the individual targets for source files. I used # to just use an implicit target, but that was found to be inadequate when I # added the library. src_files=$(find_src_files $unneeded) for f in $src_files; do o=$(replace_ext "$f" "c" "o") - SRC_TARGETS=$(printf '%s\n\n%s: %s %s\n\t$(CC) $(CFLAGS) -o %s -c %s\n' \ + o=$(basename "$o") + SRC_TARGETS=$(printf '%s\n\nsrc/%s: src %s %s\n\t$(CC) $(CFLAGS) -o src/%s -c %s\n' \ "$SRC_TARGETS" "$o" "$headers" "$f" "$o" "$f") done # Replace all the placeholders. +contents=$(replace "$contents" "ROOTDIR" "$scriptdir") +contents=$(replace "$contents" "BUILDDIR" "$builddir") + contents=$(replace "$contents" "HEADERS" "$headers") contents=$(replace "$contents" "BC_ENABLED" "$bc") contents=$(replace "$contents" "DC_ENABLED" "$dc") contents=$(replace "$contents" "BC_ALL_TESTS" "$bc_test") contents=$(replace "$contents" "BC_ALL_TESTS_NP" "$bc_test_np") contents=$(replace "$contents" "BC_TESTS" "$bc_tests") contents=$(replace "$contents" "BC_SCRIPT_TESTS" "$bc_script_tests") contents=$(replace "$contents" "BC_ERROR_TESTS" "$bc_err_tests") contents=$(replace "$contents" "BC_TEST_EXEC" "$bc_test_exec") contents=$(replace "$contents" "TIMECONST_ALL_TESTS" "$timeconst") contents=$(replace "$contents" "DC_ALL_TESTS" "$dc_test") contents=$(replace "$contents" "DC_ALL_TESTS_NP" "$dc_test_np") contents=$(replace "$contents" "DC_TESTS" "$dc_tests") contents=$(replace "$contents" "DC_SCRIPT_TESTS" "$dc_script_tests") contents=$(replace "$contents" "DC_ERROR_TESTS" "$dc_err_tests") contents=$(replace "$contents" "DC_TEST_EXEC" "$dc_test_exec") contents=$(replace "$contents" "BUILD_TYPE" "$manpage_args") contents=$(replace "$contents" "LIBRARY" "$library") contents=$(replace "$contents" "HISTORY" "$hist") contents=$(replace "$contents" "EXTRA_MATH" "$extra_math") contents=$(replace "$contents" "NLS" "$nls") contents=$(replace "$contents" "FUZZ" "$fuzz") contents=$(replace "$contents" "MEMCHECK" "$memcheck") contents=$(replace "$contents" "BC_LIB_O" "$bc_lib") contents=$(replace "$contents" "BC_HELP_O" "$bc_help") contents=$(replace "$contents" "DC_HELP_O" "$dc_help") contents=$(replace "$contents" "BC_LIB2_O" "$BC_LIB2_O") contents=$(replace "$contents" "KARATSUBA_LEN" "$karatsuba_len") contents=$(replace "$contents" "NLSPATH" "$NLSPATH") contents=$(replace "$contents" "DESTDIR" "$destdir") contents=$(replace "$contents" "EXECSUFFIX" "$EXECSUFFIX") contents=$(replace "$contents" "EXECPREFIX" "$EXECPREFIX") contents=$(replace "$contents" "BINDIR" "$BINDIR") contents=$(replace "$contents" "INCLUDEDIR" "$INCLUDEDIR") contents=$(replace "$contents" "LIBDIR" "$LIBDIR") contents=$(replace "$contents" "MAN1DIR" "$MAN1DIR") contents=$(replace "$contents" "MAN3DIR" "$MAN3DIR") contents=$(replace "$contents" "CFLAGS" "$CFLAGS") contents=$(replace "$contents" "HOSTCFLAGS" "$HOSTCFLAGS") contents=$(replace "$contents" "CPPFLAGS" "$CPPFLAGS") contents=$(replace "$contents" "LDFLAGS" "$LDFLAGS") contents=$(replace "$contents" "CC" "$CC") contents=$(replace "$contents" "HOSTCC" "$HOSTCC") contents=$(replace "$contents" "COVERAGE_OUTPUT" "$COVERAGE_OUTPUT") contents=$(replace "$contents" "COVERAGE_PREREQS" "$COVERAGE_PREREQS") contents=$(replace "$contents" "INSTALL_PREREQS" "$install_prereqs") contents=$(replace "$contents" "INSTALL_MAN_PREREQS" "$install_man_prereqs") contents=$(replace "$contents" "INSTALL_LOCALES" "$install_locales") contents=$(replace "$contents" "INSTALL_LOCALES_PREREQS" "$install_locales_prereqs") contents=$(replace "$contents" "UNINSTALL_MAN_PREREQS" "$uninstall_man_prereqs") contents=$(replace "$contents" "UNINSTALL_PREREQS" "$uninstall_prereqs") contents=$(replace "$contents" "UNINSTALL_LOCALES_PREREQS" "$uninstall_locales_prereqs") +contents=$(replace "$contents" "PC_PATH" "$PC_PATH") +contents=$(replace "$contents" "PKG_CONFIG_INSTALL" "$pkg_config_install") +contents=$(replace "$contents" "PKG_CONFIG_UNINSTALL" "$pkg_config_uninstall") + contents=$(replace "$contents" "DEFAULT_TARGET" "$default_target") contents=$(replace "$contents" "DEFAULT_TARGET_PREREQS" "$default_target_prereqs") contents=$(replace "$contents" "DEFAULT_TARGET_CMD" "$default_target_cmd") contents=$(replace "$contents" "SECOND_TARGET" "$second_target") contents=$(replace "$contents" "SECOND_TARGET_PREREQS" "$second_target_prereqs") contents=$(replace "$contents" "SECOND_TARGET_CMD" "$second_target_cmd") contents=$(replace "$contents" "ALL_PREREQ" "$ALL_PREREQ") contents=$(replace "$contents" "BC_EXEC_PREREQ" "$bc_exec_prereq") contents=$(replace "$contents" "BC_EXEC_CMD" "$bc_exec_cmd") contents=$(replace "$contents" "DC_EXEC_PREREQ" "$dc_exec_prereq") contents=$(replace "$contents" "DC_EXEC_CMD" "$dc_exec_cmd") contents=$(replace "$contents" "EXECUTABLES" "$executables") contents=$(replace "$contents" "MAIN_EXEC" "$main_exec") contents=$(replace "$contents" "EXEC" "$executable") contents=$(replace "$contents" "TESTS" "$tests") contents=$(replace "$contents" "BC_HISTORY_TEST_PREREQS" "$test_bc_history_prereqs") contents=$(replace "$contents" "DC_HISTORY_TEST_PREREQS" "$test_dc_history_prereqs") contents=$(replace "$contents" "HISTORY_TESTS" "$history_tests") contents=$(replace "$contents" "VG_BC_TEST" "$vg_bc_test") contents=$(replace "$contents" "VG_DC_TEST" "$vg_dc_test") contents=$(replace "$contents" "TIMECONST" "$timeconst") contents=$(replace "$contents" "KARATSUBA" "$karatsuba") contents=$(replace "$contents" "KARATSUBA_TEST" "$karatsuba_test") contents=$(replace "$contents" "LONG_BIT" "$LONG_BIT") contents=$(replace "$contents" "LONG_BIT_DEFINE" "$LONG_BIT_DEFINE") contents=$(replace "$contents" "GEN" "$GEN") contents=$(replace "$contents" "GEN_EXEC_TARGET" "$GEN_EXEC_TARGET") contents=$(replace "$contents" "CLEAN_PREREQS" "$CLEAN_PREREQS") contents=$(replace "$contents" "GEN_EMU" "$GEN_EMU") contents=$(replace "$contents" "BSD" "$bsd") contents=$(replace "$contents" "BC_DEFAULT_BANNER" "$bc_default_banner") contents=$(replace "$contents" "BC_DEFAULT_SIGINT_RESET" "$bc_default_sigint_reset") contents=$(replace "$contents" "DC_DEFAULT_SIGINT_RESET" "$dc_default_sigint_reset") contents=$(replace "$contents" "BC_DEFAULT_TTY_MODE" "$bc_default_tty_mode") contents=$(replace "$contents" "DC_DEFAULT_TTY_MODE" "$dc_default_tty_mode") contents=$(replace "$contents" "BC_DEFAULT_PROMPT" "$bc_default_prompt") contents=$(replace "$contents" "DC_DEFAULT_PROMPT" "$dc_default_prompt") +contents=$(replace "$contents" "BC_DEFAULT_EXPR_EXIT" "$bc_default_expr_exit") +contents=$(replace "$contents" "DC_DEFAULT_EXPR_EXIT" "$dc_default_expr_exit") # Do the first print to the Makefile. -printf '%s\n%s\n\n' "$contents" "$SRC_TARGETS" > "$scriptdir/Makefile" +printf '%s\n%s\n\n' "$contents" "$SRC_TARGETS" > "Makefile" # Generate the individual test targets. if [ "$bc" -ne 0 ]; then gen_std_tests bc "$extra_math" "$time_tests" $bc_test_exec gen_script_tests bc "$extra_math" "$generate_tests" "$time_tests" $bc_test_exec gen_err_tests bc $bc_test_exec fi if [ "$dc" -ne 0 ]; then gen_std_tests dc "$extra_math" "$time_tests" $dc_test_exec gen_script_tests dc "$extra_math" "$generate_tests" "$time_tests" $dc_test_exec gen_err_tests dc $dc_test_exec fi -cd "$scriptdir" - # Copy the correct manuals to the expected places. -cp -f manuals/bc/$manpage_args.1.md manuals/bc.1.md -cp -f manuals/bc/$manpage_args.1 manuals/bc.1 -cp -f manuals/dc/$manpage_args.1.md manuals/dc.1.md -cp -f manuals/dc/$manpage_args.1 manuals/dc.1 +mkdir -p manuals +cp -f "$scriptdir/manuals/bc/$manpage_args.1.md" manuals/bc.1.md +cp -f "$scriptdir/manuals/bc/$manpage_args.1" manuals/bc.1 +cp -f "$scriptdir/manuals/dc/$manpage_args.1.md" manuals/dc.1.md +cp -f "$scriptdir/manuals/dc/$manpage_args.1" manuals/dc.1 make clean > /dev/null diff --git a/contrib/bc/gen/bc_help.txt b/contrib/bc/gen/bc_help.txt index 9ba34c606481..36329b1d7aaf 100644 --- a/contrib/bc/gen/bc_help.txt +++ b/contrib/bc/gen/bc_help.txt @@ -1,185 +1,192 @@ /* * ***************************************************************************** * * SPDX-License-Identifier: BSD-2-Clause * * Copyright (c) 2018-2021 Gavin D. Howard and contributors. * * Redistribution and use in source and binary forms, with or without * modification, are permitted provided that the following conditions are met: * * * Redistributions of source code must retain the above copyright notice, this * list of conditions and the following disclaimer. * * * Redistributions in binary form must reproduce the above copyright notice, * this list of conditions and the following disclaimer in the documentation * and/or other materials provided with the distribution. * * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE * POSSIBILITY OF SUCH DAMAGE. * * ***************************************************************************** * * The bc help text. * */ usage: %s [options] [file...] bc is a command-line, arbitrary-precision calculator with a Turing-complete language. For details, use `man %s` or see the online documentation at https://git.yzena.com/gavin/bc/src/tag/%s/manuals/bc/%s.1.md. This bc is compatible with both the GNU bc and the POSIX bc spec. See the GNU bc manual (https://www.gnu.org/software/bc/manual/bc.html) and bc spec (http://pubs.opengroup.org/onlinepubs/9699919799/utilities/bc.html) for details. This bc has three differences to the GNU bc: 1) Arrays can be passed to the builtin "length" function to get the number of elements currently in the array. The following example prints "1": a[0] = 0 length(a[]) 2) The precedence of the boolean "not" operator (!) is equal to that of the unary minus (-), or negation, operator. This still allows POSIX-compliant scripts to work while somewhat preserving expected behavior (versus C) and making parsing easier. 3) This bc has many more extensions than the GNU bc does. For details, see the man page or online documentation. This bc also implements the dot (.) extension of the BSD bc. Options: -e expr --expression=expr Run "expr" and quit. If multiple expressions or files (see below) are given, they are all run before executing from stdin. -f file --file=file Run the bc code in "file" and exit. See above as well. -g --global-stacks Turn scale, ibase, and obase into stacks. This makes the value of each be be restored on returning from functions. See the man page or online documentation for more details. -h --help Print this usage message and exit. -i --interactive Force interactive mode. -L --no-line-length Disable line length checking. -l --mathlib Use predefined math routines: s(expr) = sine of expr in radians c(expr) = cosine of expr in radians a(expr) = arctangent of expr, returning radians l(expr) = natural log of expr e(expr) = raises e to the power of expr j(n, x) = Bessel function of integer order n of x This bc may load more functions with these options. See the manpage or online documentation for details. -P --no-prompt Disable the prompts in interactive mode. -R --no-read-prompt Disable the read prompt in interactive mode. -r keyword --redefine=keyword Redefines "keyword" and allows it to be used as a function, variable, and array name. This is useful when this bc gives parse errors on scripts meant for other bc implementations. Only keywords that are not in the POSIX bc spec may be redefined. It is a fatal error to attempt to redefine a keyword that cannot be redefined or does not exist. -q --quiet Don't print version and copyright. -s --standard Error if any non-POSIX extensions are used. -w --warn Warn if any non-POSIX extensions are used. -v --version Print version information and copyright and exit. -z --leading-zeroes Enable leading zeroes on numbers greater than -1 and less than 1. Environment variables: POSIXLY_CORRECT Error if any non-POSIX extensions are used. BC_ENV_ARGS Command-line arguments to use on every run. BC_LINE_LENGTH If an integer, the number of characters to print on a line before wrapping. Using 0 will disable line length checking. BC_BANNER If an integer and non-zero, display the copyright banner in interactive mode. Overrides the default, which is %s print the banner. BC_SIGINT_RESET If an integer and non-zero, reset on SIGINT, rather than exit, when in interactive mode. Overrides the default, which is %s. BC_TTY_MODE If an integer and non-zero, enable TTY mode when it is available. Overrides the default, which is TTY mode %s. BC_PROMPT If an integer and non-zero, enable prompt when TTY mode is possible. Overrides the default, which is prompt %s. + + BC_EXPR_EXIT + + If an integer and non-zero, exit when expressions or expression files are + given on the command-line, and does not exit when an integer and zero. + + Overrides the default, which is %s. diff --git a/contrib/bc/gen/dc_help.txt b/contrib/bc/gen/dc_help.txt index 4cf10826cd7f..a0f275b60b64 100644 --- a/contrib/bc/gen/dc_help.txt +++ b/contrib/bc/gen/dc_help.txt @@ -1,144 +1,151 @@ /* * ***************************************************************************** * * SPDX-License-Identifier: BSD-2-Clause * * Copyright (c) 2018-2021 Gavin D. Howard and contributors. * * Redistribution and use in source and binary forms, with or without * modification, are permitted provided that the following conditions are met: * * * Redistributions of source code must retain the above copyright notice, this * list of conditions and the following disclaimer. * * * Redistributions in binary form must reproduce the above copyright notice, * this list of conditions and the following disclaimer in the documentation * and/or other materials provided with the distribution. * * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE * POSSIBILITY OF SUCH DAMAGE. * * ***************************************************************************** * * The dc help text. * */ usage: %s [options] [file...] dc is a reverse-polish notation command-line calculator which supports unlimited precision arithmetic. For details, use `man %s` or see the online documentation at https://git.yzena.com/gavin/bc/src/tag/%s/manuals/bc/%s.1.md. This dc is (mostly) compatible with the OpenBSD dc and the GNU dc. See the OpenBSD man page (http://man.openbsd.org/OpenBSD-current/man1/dc.1) and the GNU dc manual (https://www.gnu.org/software/bc/manual/dc-1.05/html_mono/dc.html) for details. This dc has a few differences from the two above: 1) When printing a byte stream (command "P"), this bc follows what the FreeBSD dc does. 2) This dc implements the GNU extensions for divmod ("~") and modular exponentiation ("|"). 3) This dc implements all FreeBSD extensions, except for "J" and "M". 4) This dc does not implement the run command ("!"), for security reasons. 5) Like the FreeBSD dc, this dc supports extended registers. However, they are implemented differently. When it encounters whitespace where a register should be, it skips the whitespace. If the character following is not a lowercase letter, an error is issued. Otherwise, the register name is parsed by the following regex: [a-z][a-z0-9_]* This generally means that register names will be surrounded by whitespace. Examples: l idx s temp L index S temp2 < do_thing Also note that, unlike the FreeBSD dc, extended registers are not even parsed unless the "-x" option is given. Instead, the space after a command that requires a register name is taken as the register name. Options: -e expr --expression=expr Run "expr" and quit. If multiple expressions or files (see below) are given, they are all run. After running, dc will exit. -f file --file=file Run the dc code in "file" and exit. See above. -h --help Print this usage message and exit. -i --interactive Put dc into interactive mode. See the man page for more details. -L --no-line-length Disable line length checking. -P --no-prompt Disable the prompts in interactive mode. -R --no-read-prompt Disable the read prompt in interactive mode. -V --version Print version and copyright and exit. -x --extended-register Enable extended register mode. -z --leading-zeroes Enable leading zeroes on numbers greater than -1 and less than 1. Environment variables: DC_ENV_ARGS Command-line arguments to use on every run. DC_LINE_LENGTH If an integer, the number of characters to print on a line before wrapping. Using 0 will disable line length checking. DC_SIGINT_RESET If an integer and non-zero, reset on SIGINT, rather than exit, when in interactive mode. Overrides the default, which is %s. DC_TTY_MODE If an integer and non-zero, enable TTY mode when it is available. Overrides the default, which is TTY mode %s. DC_PROMPT If an integer and non-zero, enable prompt when TTY mode is possible. Overrides the default, which is prompt %s. + + DC_EXPR_EXIT + + If an integer and non-zero, exit when expressions or expression files are + given on the command-line, and does not exit when an integer and zero. + + Overrides the default, which is %s. diff --git a/contrib/bc/include/status.h b/contrib/bc/include/status.h index 662f2b89c04d..993b5e698fb3 100644 --- a/contrib/bc/include/status.h +++ b/contrib/bc/include/status.h @@ -1,793 +1,805 @@ /* * ***************************************************************************** * * SPDX-License-Identifier: BSD-2-Clause * * Copyright (c) 2018-2021 Gavin D. Howard and contributors. * * Redistribution and use in source and binary forms, with or without * modification, are permitted provided that the following conditions are met: * * * Redistributions of source code must retain the above copyright notice, this * list of conditions and the following disclaimer. * * * Redistributions in binary form must reproduce the above copyright notice, * this list of conditions and the following disclaimer in the documentation * and/or other materials provided with the distribution. * * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE * POSSIBILITY OF SUCH DAMAGE. * * ***************************************************************************** * * All bc status codes and cross-platform portability. * */ #ifndef BC_STATUS_H #define BC_STATUS_H #include // This is used by configure.sh to test for OpenBSD. #ifdef BC_TEST_OPENBSD #ifdef __OpenBSD__ #error On OpenBSD without _BSD_SOURCE #endif // __OpenBSD__ #endif // BC_TEST_OPENBSD #ifndef BC_ENABLED #define BC_ENABLED (1) #endif // BC_ENABLED #ifndef DC_ENABLED #define DC_ENABLED (1) #endif // DC_ENABLED #ifndef BC_ENABLE_LIBRARY #define BC_ENABLE_LIBRARY (0) #endif // BC_ENABLE_LIBRARY // This is error checking for fuzz builds. #if BC_ENABLE_AFL #ifndef __AFL_HAVE_MANUAL_CONTROL #error Must compile with afl-clang-fast or afl-clang-lto for fuzzing #endif // __AFL_HAVE_MANUAL_CONTROL #endif // BC_ENABLE_AFL #ifndef BC_ENABLE_MEMCHECK #define BC_ENABLE_MEMCHECK (0) #endif // BC_ENABLE_MEMCHECK /** * Mark a variable as unused. * @param e The variable to mark as unused. */ #define BC_UNUSED(e) ((void) (e)) // If users want, they can define this to something like __builtin_expect(e, 1). // It might give a performance improvement. #ifndef BC_LIKELY /** * Mark a branch expression as likely. * @param e The expression to mark as likely. */ #define BC_LIKELY(e) (e) #endif // BC_LIKELY // If users want, they can define this to something like __builtin_expect(e, 0). // It might give a performance improvement. #ifndef BC_UNLIKELY /** * Mark a branch expression as unlikely. * @param e The expression to mark as unlikely. */ #define BC_UNLIKELY(e) (e) #endif // BC_UNLIKELY /** * Mark a branch expression as an error, if true. * @param e The expression to mark as an error, if true. */ #define BC_ERR(e) BC_UNLIKELY(e) /** * Mark a branch expression as not an error, if true. * @param e The expression to mark as not an error, if true. */ #define BC_NO_ERR(s) BC_LIKELY(s) // Disable extra debug code by default. #ifndef BC_DEBUG_CODE #define BC_DEBUG_CODE (0) #endif // BC_DEBUG_CODE // We want to be able to use _Noreturn on C11 compilers. #if __STDC_VERSION__ >= 201100L #include #define BC_NORETURN _Noreturn #define BC_C11 (1) #else // __STDC_VERSION__ #define BC_NORETURN #define BC_MUST_RETURN #define BC_C11 (0) #endif // __STDC_VERSION__ #define BC_HAS_UNREACHABLE (0) #define BC_HAS_COMPUTED_GOTO (0) // GCC and Clang complain if fallthroughs are not marked with their special // attribute. Jerks. This creates a define for marking the fallthroughs that is // nothing on other compilers. #if defined(__clang__) || defined(__GNUC__) #if defined(__has_attribute) #if __has_attribute(fallthrough) #define BC_FALLTHROUGH __attribute__((fallthrough)); #else // __has_attribute(fallthrough) #define BC_FALLTHROUGH #endif // __has_attribute(fallthrough) #ifdef __GNUC__ #if __GNUC__ > 4 || (__GNUC__ == 4 && __GNUC_MINOR__ >= 5) #undef BC_HAS_UNREACHABLE #define BC_HAS_UNREACHABLE (1) #endif // __GNUC__ > 4 || (__GNUC__ == 4 && __GNUC_MINOR__ >= 5) #else // __GNUC__ #if __clang_major__ >= 4 #undef BC_HAS_UNREACHABLE #define BC_HAS_UNREACHABLE (1) #endif // __clang_major__ >= 4 #endif // __GNUC__ #else // defined(__has_attribute) #define BC_FALLTHROUGH #endif // defined(__has_attribute) #else // defined(__clang__) || defined(__GNUC__) #define BC_FALLTHROUGH #endif // defined(__clang__) || defined(__GNUC__) #if BC_HAS_UNREACHABLE #define BC_UNREACHABLE __builtin_unreachable(); #else // BC_HAS_UNREACHABLE #ifdef _WIN32 #define BC_UNREACHABLE __assume(0); #else // _WIN32 #define BC_UNREACHABLE #endif // _WIN32 #endif // BC_HAS_UNREACHABLE #ifdef __GNUC__ #if __GNUC__ > 4 || (__GNUC__ == 4 && __GNUC_MINOR__ >= 5) #undef BC_HAS_COMPUTED_GOTO #define BC_HAS_COMPUTED_GOTO (1) #endif // __GNUC__ > 4 || (__GNUC__ == 4 && __GNUC_MINOR__ >= 5) #endif // __GNUC__ #ifdef __clang__ #if __clang_major__ >= 4 #undef BC_HAS_COMPUTED_GOTO #define BC_HAS_COMPUTED_GOTO (1) #endif // __clang_major__ >= 4 #endif // __GNUC__ #ifdef BC_NO_COMPUTED_GOTO #undef BC_HAS_COMPUTED_GOTO #define BC_HAS_COMPUTED_GOTO (0) #endif // BC_NO_COMPUTED_GOTO #ifdef __GNUC__ #ifdef __OpenBSD__ // The OpenBSD GCC doesn't like inline. #define inline #endif // __OpenBSD__ #endif // __GNUC__ // Workarounds for AIX's POSIX incompatibility. #ifndef SIZE_MAX #define SIZE_MAX __SIZE_MAX__ #endif // SIZE_MAX #ifndef UINTMAX_C #define UINTMAX_C __UINTMAX_C #endif // UINTMAX_C #ifndef UINT32_C #define UINT32_C __UINT32_C #endif // UINT32_C #ifndef UINT_FAST32_MAX #define UINT_FAST32_MAX __UINT_FAST32_MAX__ #endif // UINT_FAST32_MAX #ifndef UINT16_MAX #define UINT16_MAX __UINT16_MAX__ #endif // UINT16_MAX #ifndef SIG_ATOMIC_MAX #define SIG_ATOMIC_MAX __SIG_ATOMIC_MAX__ #endif // SIG_ATOMIC_MAX // Yes, this has to be here. #include // All of these set defaults for settings. #if BC_ENABLED #ifndef BC_DEFAULT_BANNER #define BC_DEFAULT_BANNER (0) #endif // BC_DEFAULT_BANNER #endif // BC_ENABLED #ifndef BC_DEFAULT_SIGINT_RESET #define BC_DEFAULT_SIGINT_RESET (1) #endif // BC_DEFAULT_SIGINT_RESET #ifndef BC_DEFAULT_TTY_MODE #define BC_DEFAULT_TTY_MODE (1) #endif // BC_DEFAULT_TTY_MODE #ifndef BC_DEFAULT_PROMPT #define BC_DEFAULT_PROMPT BC_DEFAULT_TTY_MODE #endif // BC_DEFAULT_PROMPT +#ifndef BC_DEFAULT_EXPR_EXIT +#define BC_DEFAULT_EXPR_EXIT (1) +#endif // BC_DEFAULT_EXPR_EXIT + // All of these set defaults for settings. #ifndef DC_DEFAULT_SIGINT_RESET #define DC_DEFAULT_SIGINT_RESET (1) #endif // DC_DEFAULT_SIGINT_RESET #ifndef DC_DEFAULT_TTY_MODE #define DC_DEFAULT_TTY_MODE (0) #endif // DC_DEFAULT_TTY_MODE #ifndef DC_DEFAULT_HISTORY #define DC_DEFAULT_HISTORY DC_DEFAULT_TTY_MODE #endif // DC_DEFAULT_HISTORY #ifndef DC_DEFAULT_PROMPT #define DC_DEFAULT_PROMPT DC_DEFAULT_TTY_MODE #endif // DC_DEFAULT_PROMPT +#ifndef DC_DEFAULT_EXPR_EXIT +#define DC_DEFAULT_EXPR_EXIT (1) +#endif // DC_DEFAULT_EXPR_EXIT + /// Statuses, which mark either which category of error happened, or some other /// status that matters. typedef enum BcStatus { /// Normal status. BC_STATUS_SUCCESS = 0, /// Math error. BC_STATUS_ERROR_MATH, /// Parse (and lex) error. BC_STATUS_ERROR_PARSE, /// Runtime error. BC_STATUS_ERROR_EXEC, /// Fatal error. BC_STATUS_ERROR_FATAL, /// EOF status. BC_STATUS_EOF, /// Quit status. This means that bc/dc is in the process of quitting. BC_STATUS_QUIT, } BcStatus; /// Errors, which are more specific errors. typedef enum BcErr { // Math errors. /// Negative number used when not allowed. BC_ERR_MATH_NEGATIVE, /// Non-integer used when not allowed. BC_ERR_MATH_NON_INTEGER, /// Conversion to a hardware integer would overflow. BC_ERR_MATH_OVERFLOW, /// Divide by zero. BC_ERR_MATH_DIVIDE_BY_ZERO, // Fatal errors. /// An allocation or reallocation failed. BC_ERR_FATAL_ALLOC_ERR, /// I/O failure. BC_ERR_FATAL_IO_ERR, /// File error, such as permissions or file does not exist. BC_ERR_FATAL_FILE_ERR, /// File is binary, not text, error. BC_ERR_FATAL_BIN_FILE, /// Attempted to read a directory as a file error. BC_ERR_FATAL_PATH_DIR, /// Invalid option error. BC_ERR_FATAL_OPTION, /// Option with required argument not given an argument. BC_ERR_FATAL_OPTION_NO_ARG, /// Option with no argument given an argument. BC_ERR_FATAL_OPTION_ARG, /// Option argument is invalid. BC_ERR_FATAL_ARG, // Runtime errors. /// Invalid ibase value. BC_ERR_EXEC_IBASE, /// Invalid obase value. BC_ERR_EXEC_OBASE, /// Invalid scale value. BC_ERR_EXEC_SCALE, /// Invalid expression parsed by read(). BC_ERR_EXEC_READ_EXPR, /// read() used within an expression given to a read() call. BC_ERR_EXEC_REC_READ, /// Type error. BC_ERR_EXEC_TYPE, /// Stack has too few elements error. BC_ERR_EXEC_STACK, /// Register stack has too few elements error. BC_ERR_EXEC_STACK_REGISTER, /// Wrong number of arguments error. BC_ERR_EXEC_PARAMS, /// Undefined function error. BC_ERR_EXEC_UNDEF_FUNC, /// Void value used in an expression error. BC_ERR_EXEC_VOID_VAL, // Parse (and lex errors). /// EOF encountered when not expected error. BC_ERR_PARSE_EOF, /// Invalid character error. BC_ERR_PARSE_CHAR, /// Invalid string (no ending quote) error. BC_ERR_PARSE_STRING, /// Invalid comment (no end found) error. BC_ERR_PARSE_COMMENT, /// Invalid token encountered error. BC_ERR_PARSE_TOKEN, #if BC_ENABLED /// Invalid expression error. BC_ERR_PARSE_EXPR, /// Expression is empty error. BC_ERR_PARSE_EMPTY_EXPR, /// Print statement is invalid error. BC_ERR_PARSE_PRINT, /// Function definition is invalid error. BC_ERR_PARSE_FUNC, /// Assignment is invalid error. BC_ERR_PARSE_ASSIGN, /// No auto identifiers given for an auto statement error. BC_ERR_PARSE_NO_AUTO, /// Duplicate local (parameter or auto) error. BC_ERR_PARSE_DUP_LOCAL, /// Invalid block (within braces) error. BC_ERR_PARSE_BLOCK, /// Invalid return statement for void functions. BC_ERR_PARSE_RET_VOID, /// Reference attached to a variable, not an array, error. BC_ERR_PARSE_REF_VAR, // POSIX-only errors. /// Name length greater than 1 error. BC_ERR_POSIX_NAME_LEN, /// Non-POSIX comment used error. BC_ERR_POSIX_COMMENT, /// Non-POSIX keyword error. BC_ERR_POSIX_KW, /// Non-POSIX . (last) error. BC_ERR_POSIX_DOT, /// Non-POSIX return error. BC_ERR_POSIX_RET, /// Non-POSIX boolean operator used error. BC_ERR_POSIX_BOOL, /// POSIX relation operator used outside if, while, or for statements error. BC_ERR_POSIX_REL_POS, /// Multiple POSIX relation operators used in an if, while, or for statement /// error. BC_ERR_POSIX_MULTIREL, /// Empty statements in POSIX for loop error. BC_ERR_POSIX_FOR, + /// POSIX's grammar does not allow a function definition right after a + /// semicolon. + BC_ERR_POSIX_FUNC_AFTER_SEMICOLON, + /// Non-POSIX exponential (scientific or engineering) number used error. BC_ERR_POSIX_EXP_NUM, /// Non-POSIX array reference error. BC_ERR_POSIX_REF, /// Non-POSIX void error. BC_ERR_POSIX_VOID, /// Non-POSIX brace position used error. BC_ERR_POSIX_BRACE, /// String used in expression. BC_ERR_POSIX_EXPR_STRING, #endif // BC_ENABLED // Number of elements. BC_ERR_NELEMS, #if BC_ENABLED /// A marker for the start of POSIX errors. BC_ERR_POSIX_START = BC_ERR_POSIX_NAME_LEN, /// A marker for the end of POSIX errors. BC_ERR_POSIX_END = BC_ERR_POSIX_EXPR_STRING, #endif // BC_ENABLED } BcErr; // The indices of each category of error in bc_errs[], and used in bc_err_ids[] // to associate actual errors with their categories. /// Math error category. #define BC_ERR_IDX_MATH (0) /// Parse (and lex) error category. #define BC_ERR_IDX_PARSE (1) /// Runtime error category. #define BC_ERR_IDX_EXEC (2) /// Fatal error category. #define BC_ERR_IDX_FATAL (3) /// Number of categories. #define BC_ERR_IDX_NELEMS (4) // If bc is enabled, we add an extra category for POSIX warnings. #if BC_ENABLED /// POSIX warning category. #define BC_ERR_IDX_WARN (BC_ERR_IDX_NELEMS) #endif // BC_ENABLED /// Do a longjmp(). This is what to use when activating an "exception", i.e., a /// longjmp(). With debug code, it will print the name of the function it jumped /// from. #if BC_DEBUG_CODE #define BC_JMP bc_vm_jmp(__func__) #else // BC_DEBUG_CODE #define BC_JMP bc_vm_jmp() #endif // BC_DEBUG_CODE /// Returns true if an exception is in flight, false otherwise. #define BC_SIG_EXC \ BC_UNLIKELY(vm.status != (sig_atomic_t) BC_STATUS_SUCCESS || vm.sig) /// Returns true if there is *no* exception in flight, false otherwise. #define BC_NO_SIG_EXC \ BC_LIKELY(vm.status == (sig_atomic_t) BC_STATUS_SUCCESS && !vm.sig) #ifndef NDEBUG /// Assert that signals are locked. There are non-async-signal-safe functions in /// bc, and they *must* have signals locked. Other functions are expected to /// *not* have signals locked, for reasons. So this is a pre-built assert /// (no-op in non-debug mode) that check that signals are locked. #define BC_SIG_ASSERT_LOCKED do { assert(vm.sig_lock); } while (0) /// Assert that signals are unlocked. There are non-async-signal-safe functions /// in bc, and they *must* have signals locked. Other functions are expected to /// *not* have signals locked, for reasons. So this is a pre-built assert /// (no-op in non-debug mode) that check that signals are unlocked. #define BC_SIG_ASSERT_NOT_LOCKED do { assert(vm.sig_lock == 0); } while (0) #else // NDEBUG /// Assert that signals are locked. There are non-async-signal-safe functions in /// bc, and they *must* have signals locked. Other functions are expected to /// *not* have signals locked, for reasons. So this is a pre-built assert /// (no-op in non-debug mode) that check that signals are locked. #define BC_SIG_ASSERT_LOCKED /// Assert that signals are unlocked. There are non-async-signal-safe functions /// in bc, and they *must* have signals locked. Other functions are expected to /// *not* have signals locked, for reasons. So this is a pre-built assert /// (no-op in non-debug mode) that check that signals are unlocked. #define BC_SIG_ASSERT_NOT_LOCKED #endif // NDEBUG /// Locks signals. #define BC_SIG_LOCK \ do { \ BC_SIG_ASSERT_NOT_LOCKED; \ vm.sig_lock = 1; \ } while (0) /// Unlocks signals. If a signal happened, then this will cause a jump. #define BC_SIG_UNLOCK \ do { \ BC_SIG_ASSERT_LOCKED; \ vm.sig_lock = 0; \ if (vm.sig) BC_JMP; \ } while (0) /// Locks signals, regardless of if they are already locked. This is really only /// used after labels that longjmp() goes to after the jump because the cleanup /// code must have signals locked, and BC_LONGJMP_CONT will unlock signals if it /// doesn't jump. #define BC_SIG_MAYLOCK \ do { \ vm.sig_lock = 1; \ } while (0) /// Unlocks signals, regardless of if they were already unlocked. If a signal /// happened, then this will cause a jump. #define BC_SIG_MAYUNLOCK \ do { \ vm.sig_lock = 0; \ if (vm.sig) BC_JMP; \ } while (0) /* * Locks signals, but stores the old lock state, to be restored later by * BC_SIG_TRYUNLOCK. * @param v The variable to store the old lock state to. */ #define BC_SIG_TRYLOCK(v) \ do { \ v = vm.sig_lock; \ vm.sig_lock = 1; \ } while (0) /* Restores the previous state of a signal lock, and if it is now unlocked, * initiates an exception/jump. * @param v The old lock state. */ #define BC_SIG_TRYUNLOCK(v) \ do { \ vm.sig_lock = (v); \ if (!(v) && vm.sig) BC_JMP; \ } while (0) /** * Sets a jump, and sets it up as well so that if a longjmp() happens, bc will * immediately goto a label where some cleanup code is. This one assumes that * signals are not locked and will lock them, set the jump, and unlock them. * Setting the jump also includes pushing the jmp_buf onto the jmp_buf stack. * This grows the jmp_bufs vector first to prevent a fatal error from happening * after the setjmp(). This is done because BC_SETJMP(l) is assumed to be used * *before* the actual initialization calls that need the setjmp(). * param l The label to jump to on a longjmp(). */ #define BC_SETJMP(l) \ do { \ sigjmp_buf sjb; \ BC_SIG_LOCK; \ bc_vec_grow(&vm.jmp_bufs, 1); \ if (sigsetjmp(sjb, 0)) { \ assert(BC_SIG_EXC); \ goto l; \ } \ bc_vec_push(&vm.jmp_bufs, &sjb); \ BC_SIG_UNLOCK; \ } while (0) /** * Sets a jump like BC_SETJMP, but unlike BC_SETJMP, it assumes signals are * locked and will just set the jump. This does *not* have a call to * bc_vec_grow() because it is assumed that BC_SETJMP_LOCKED(l) is used *after* * the initializations that need the setjmp(). * param l The label to jump to on a longjmp(). */ #define BC_SETJMP_LOCKED(l) \ do { \ sigjmp_buf sjb; \ BC_SIG_ASSERT_LOCKED; \ if (sigsetjmp(sjb, 0)) { \ assert(BC_SIG_EXC); \ goto l; \ } \ bc_vec_push(&vm.jmp_bufs, &sjb); \ } while (0) /// Used after cleanup labels set by BC_SETJMP and BC_SETJMP_LOCKED to jump to /// the next place. This is what continues the stack unwinding. This basically /// copies BC_SIG_UNLOCK into itself, but that is because its condition for /// jumping is BC_SIG_EXC, not just that a signal happened. #define BC_LONGJMP_CONT \ do { \ BC_SIG_ASSERT_LOCKED; \ if (!vm.sig_pop) bc_vec_pop(&vm.jmp_bufs); \ vm.sig_lock = 0; \ if (BC_SIG_EXC) BC_JMP; \ } while (0) /// Unsets a jump. It always assumes signals are locked. This basically just /// pops a jmp_buf off of the stack of jmp_bufs, and since the jump mechanism /// always jumps to the location at the top of the stack, this effectively /// undoes a setjmp(). #define BC_UNSETJMP \ do { \ BC_SIG_ASSERT_LOCKED; \ bc_vec_pop(&vm.jmp_bufs); \ } while (0) /// Stops a stack unwinding. Technically, a stack unwinding needs to be done /// manually, but it will always be done unless certain flags are cleared. This /// clears the flags. #define BC_LONGJMP_STOP \ do { \ vm.sig_pop = 0; \ vm.sig = 0; \ } while (0) // Various convenience macros for calling the bc's error handling routine. #if BC_ENABLE_LIBRARY /** * Call bc's error handling routine. * @param e The error. * @param l The line of the script that the error happened. * @param ... Extra arguments for error messages as necessary. */ #define bc_error(e, l, ...) (bc_vm_handleError((e))) /** * Call bc's error handling routine. * @param e The error. */ #define bc_err(e) (bc_vm_handleError((e))) /** * Call bc's error handling routine. * @param e The error. */ #define bc_verr(e, ...) (bc_vm_handleError((e))) #else // BC_ENABLE_LIBRARY /** * Call bc's error handling routine. * @param e The error. * @param l The line of the script that the error happened. * @param ... Extra arguments for error messages as necessary. */ #define bc_error(e, l, ...) (bc_vm_handleError((e), (l), __VA_ARGS__)) /** * Call bc's error handling routine. * @param e The error. */ #define bc_err(e) (bc_vm_handleError((e), 0)) /** * Call bc's error handling routine. * @param e The error. */ #define bc_verr(e, ...) (bc_vm_handleError((e), 0, __VA_ARGS__)) #endif // BC_ENABLE_LIBRARY /** * Returns true if status @a s is an error, false otherwise. * @param s The status to test. * @return True if @a s is an error, false otherwise. */ #define BC_STATUS_IS_ERROR(s) \ ((s) >= BC_STATUS_ERROR_MATH && (s) <= BC_STATUS_ERROR_FATAL) // Convenience macros that can be placed at the beginning and exits of functions // for easy marking of where functions are entered and exited. #if BC_DEBUG_CODE #define BC_FUNC_ENTER \ do { \ size_t bc_func_enter_i; \ for (bc_func_enter_i = 0; bc_func_enter_i < vm.func_depth; \ ++bc_func_enter_i) \ { \ bc_file_puts(&vm.ferr, bc_flush_none, " "); \ } \ vm.func_depth += 1; \ bc_file_printf(&vm.ferr, "Entering %s\n", __func__); \ bc_file_flush(&vm.ferr, bc_flush_none); \ } while (0); #define BC_FUNC_EXIT \ do { \ size_t bc_func_enter_i; \ vm.func_depth -= 1; \ for (bc_func_enter_i = 0; bc_func_enter_i < vm.func_depth; \ ++bc_func_enter_i) \ { \ bc_file_puts(&vm.ferr, bc_flush_none, " "); \ } \ bc_file_printf(&vm.ferr, "Leaving %s\n", __func__); \ bc_file_flush(&vm.ferr, bc_flush_none); \ } while (0); #else // BC_DEBUG_CODE #define BC_FUNC_ENTER #define BC_FUNC_EXIT #endif // BC_DEBUG_CODE #endif // BC_STATUS_H diff --git a/contrib/bc/include/version.h b/contrib/bc/include/version.h index 72500c8e3f28..eca73baf508f 100644 --- a/contrib/bc/include/version.h +++ b/contrib/bc/include/version.h @@ -1,42 +1,42 @@ /* * ***************************************************************************** * * SPDX-License-Identifier: BSD-2-Clause * * Copyright (c) 2018-2021 Gavin D. Howard and contributors. * * Redistribution and use in source and binary forms, with or without * modification, are permitted provided that the following conditions are met: * * * Redistributions of source code must retain the above copyright notice, this * list of conditions and the following disclaimer. * * * Redistributions in binary form must reproduce the above copyright notice, * this list of conditions and the following disclaimer in the documentation * and/or other materials provided with the distribution. * * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE * POSSIBILITY OF SUCH DAMAGE. * * ***************************************************************************** * * The version of bc. * */ #ifndef BC_VERSION_H #define BC_VERSION_H /// The current version. -#define VERSION 5.1.1 +#define VERSION 5.2.1 #endif // BC_VERSION_H diff --git a/contrib/bc/include/vm.h b/contrib/bc/include/vm.h index bbc5e57e2ac8..d6f698fb1e6d 100644 --- a/contrib/bc/include/vm.h +++ b/contrib/bc/include/vm.h @@ -1,876 +1,882 @@ /* * ***************************************************************************** * * SPDX-License-Identifier: BSD-2-Clause * * Copyright (c) 2018-2021 Gavin D. Howard and contributors. * * Redistribution and use in source and binary forms, with or without * modification, are permitted provided that the following conditions are met: * * * Redistributions of source code must retain the above copyright notice, this * list of conditions and the following disclaimer. * * * Redistributions in binary form must reproduce the above copyright notice, * this list of conditions and the following disclaimer in the documentation * and/or other materials provided with the distribution. * * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE * POSSIBILITY OF SUCH DAMAGE. * * ***************************************************************************** * * Definitions for bc's VM. * */ #ifndef BC_VM_H #define BC_VM_H #include #include #include #include #if BC_ENABLE_NLS #ifdef _WIN32 #error NLS is not supported on Windows. #endif // _WIN32 #include #endif // BC_ENABLE_NLS #include #include #include #include #include #include #include #include // We don't want to include this file for the library because it's unused. #if !BC_ENABLE_LIBRARY #include #endif // !BC_ENABLE_LIBRARY // This should be obvious. If neither calculator is enabled, barf. #if !BC_ENABLED && !DC_ENABLED #error Must define BC_ENABLED, DC_ENABLED, or both #endif // CHAR_BIT must be at least 6, for various reasons. I might want to bump this // to 8 in the future. #if CHAR_BIT < 6 #error CHAR_BIT must be at least 6. #endif // Set defaults. // #ifndef BC_ENABLE_NLS #define BC_ENABLE_NLS (0) #endif // BC_ENABLE_NLS #ifndef MAINEXEC #define MAINEXEC bc #endif // MAINEXEC #ifndef _WIN32 #ifndef EXECPREFIX #define EXECPREFIX #endif // EXECPREFIX #else // _WIN32 #undef EXECPREFIX #endif // _WIN32 /** * Generate a string from text. * @parm V The text to generate a string for. */ #define GEN_STR(V) #V /** * Help generate a string from text. The preprocessor requires this two-step * process. Trust me. * @parm V The text to generate a string for. */ #define GEN_STR2(V) GEN_STR(V) /// The version as a string. VERSION must be defined previously, usually by the /// build system. #define BC_VERSION GEN_STR2(VERSION) /// The main executable name as a string. MAINEXEC must be defined previously, /// usually by the build system. #define BC_MAINEXEC GEN_STR2(MAINEXEC) /// The build type as a string. BUILD_TYPE must be defined previously, usually /// by the build system. #define BC_BUILD_TYPE GEN_STR2(BUILD_TYPE) // We only allow an empty executable prefix on Windows. #ifndef _WIN32 #define BC_EXECPREFIX GEN_STR2(EXECPREFIX) #else // _WIN32 #define BC_EXECPREFIX "" #endif // _WIN32 #if !BC_ENABLE_LIBRARY #if DC_ENABLED /// The flag for the extended register option. #define DC_FLAG_X (UINTMAX_C(1)<<0) #endif // DC_ENABLED #if BC_ENABLED /// The flag for the POSIX warning option. #define BC_FLAG_W (UINTMAX_C(1)<<1) /// The flag for the POSIX error option. #define BC_FLAG_S (UINTMAX_C(1)<<2) /// The flag for the math library option. #define BC_FLAG_L (UINTMAX_C(1)<<3) /// The flag for the global stacks option. #define BC_FLAG_G (UINTMAX_C(1)<<4) #endif // BC_ENABLED /// The flag for quiet, though this one is reversed; the option clears the flag. #define BC_FLAG_Q (UINTMAX_C(1)<<5) /// The flag for interactive. #define BC_FLAG_I (UINTMAX_C(1)<<6) /// The flag for prompt. This is also reversed; the option clears the flag. #define BC_FLAG_P (UINTMAX_C(1)<<7) /// The flag for read prompt. This is also reversed; the option clears the flag. #define BC_FLAG_R (UINTMAX_C(1)<<8) /// The flag for a leading zero. #define BC_FLAG_Z (UINTMAX_C(1)<<9) /// The flag for stdin being a TTY. #define BC_FLAG_TTYIN (UINTMAX_C(1)<<10) /// The flag for TTY mode. #define BC_FLAG_TTY (UINTMAX_C(1)<<11) /// The flag for reset on SIGINT. #define BC_FLAG_SIGINT (UINTMAX_C(1)<<12) +/// The flag for exiting with expressions. +#define BC_FLAG_EXPR_EXIT (UINTMAX_C(1)<<13) + /// A convenience macro for getting the TTYIN flag. #define BC_TTYIN (vm.flags & BC_FLAG_TTYIN) /// A convenience macro for getting the TTY flag. #define BC_TTY (vm.flags & BC_FLAG_TTY) /// A convenience macro for getting the SIGINT flag. #define BC_SIGINT (vm.flags & BC_FLAG_SIGINT) #if BC_ENABLED /// A convenience macro for getting the POSIX error flag. #define BC_S (vm.flags & BC_FLAG_S) /// A convenience macro for getting the POSIX warning flag. #define BC_W (vm.flags & BC_FLAG_W) /// A convenience macro for getting the math library flag. #define BC_L (vm.flags & BC_FLAG_L) /// A convenience macro for getting the global stacks flag. #define BC_G (vm.flags & BC_FLAG_G) #endif // BC_ENABLED #if DC_ENABLED /// A convenience macro for getting the extended register flag. #define DC_X (vm.flags & DC_FLAG_X) #endif // DC_ENABLED /// A convenience macro for getting the interactive flag. #define BC_I (vm.flags & BC_FLAG_I) /// A convenience macro for getting the prompt flag. #define BC_P (vm.flags & BC_FLAG_P) /// A convenience macro for getting the read prompt flag. #define BC_R (vm.flags & BC_FLAG_R) /// A convenience macro for getting the leading zero flag. #define BC_Z (vm.flags & BC_FLAG_Z) +/// A convenience macro for getting the expression exit flag. +#define BC_EXPR_EXIT (vm.flags & BC_FLAG_EXPR_EXIT) + #if BC_ENABLED /// A convenience macro for checking if bc is in POSIX mode. #define BC_IS_POSIX (BC_S || BC_W) #if DC_ENABLED /// Returns true if bc is running. #define BC_IS_BC (vm.name[0] != 'd') /// Returns true if dc is running. #define BC_IS_DC (vm.name[0] == 'd') #else // DC_ENABLED /// Returns true if bc is running. #define BC_IS_BC (1) /// Returns true if dc is running. #define BC_IS_DC (0) #endif // DC_ENABLED #else // BC_ENABLED /// A convenience macro for checking if bc is in POSIX mode. #define BC_IS_POSIX (0) /// Returns true if bc is running. #define BC_IS_BC (0) /// Returns true if dc is running. #define BC_IS_DC (1) #endif // BC_ENABLED /// A convenience macro for checking if the prompt is enabled. #define BC_PROMPT (BC_P) #else // !BC_ENABLE_LIBRARY #define BC_Z (vm.leading_zeroes) #endif // !BC_ENABLE_LIBRARY /** * Returns the max of its two arguments. This evaluates arguments twice, so be * careful what args you give it. * @param a The first argument. * @param b The second argument. * @return The max of the two arguments. */ #define BC_MAX(a, b) ((a) > (b) ? (a) : (b)) /** * Returns the min of its two arguments. This evaluates arguments twice, so be * careful what args you give it. * @param a The first argument. * @param b The second argument. * @return The min of the two arguments. */ #define BC_MIN(a, b) ((a) < (b) ? (a) : (b)) /// Returns the max obase that is allowed. #define BC_MAX_OBASE ((BcBigDig) (BC_BASE_POW)) /// Returns the max array size that is allowed. #define BC_MAX_DIM ((BcBigDig) (SIZE_MAX - 1)) /// Returns the max scale that is allowed. #define BC_MAX_SCALE ((BcBigDig) (BC_NUM_BIGDIG_MAX - 1)) /// Returns the max string length that is allowed. #define BC_MAX_STRING ((BcBigDig) (BC_NUM_BIGDIG_MAX - 1)) /// Returns the max identifier length that is allowed. #define BC_MAX_NAME BC_MAX_STRING /// Returns the max number size that is allowed. #define BC_MAX_NUM BC_MAX_SCALE #if BC_ENABLE_EXTRA_MATH /// Returns the max random integer that can be returned. #define BC_MAX_RAND ((BcBigDig) (((BcRand) 0) - 1)) #endif // BC_ENABLE_EXTRA_MATH /// Returns the max exponent that is allowed. #define BC_MAX_EXP ((ulong) (BC_NUM_BIGDIG_MAX)) /// Returns the max number of variables that is allowed. #define BC_MAX_VARS ((ulong) (SIZE_MAX - 1)) /// The size of the global buffer. #define BC_VM_BUF_SIZE (1<<12) /// The amount of the global buffer allocated to stdout. #define BC_VM_STDOUT_BUF_SIZE (1<<11) /// The amount of the global buffer allocated to stderr. #define BC_VM_STDERR_BUF_SIZE (1<<10) /// The amount of the global buffer allocated to stdin. #define BC_VM_STDIN_BUF_SIZE (BC_VM_STDERR_BUF_SIZE - 1) /// The max number of temporary BcNums that can be kept. #define BC_VM_MAX_TEMPS (1 << 9) /// The capacity of the one BcNum, which is a constant. #define BC_VM_ONE_CAP (1) /** * Returns true if a BcResult is safe for garbage collection. * @param r The BcResult to test. * @return True if @a r is safe to garbage collect. */ #define BC_VM_SAFE_RESULT(r) ((r)->t >= BC_RESULT_TEMP) /// The invalid locale catalog return value. #define BC_VM_INVALID_CATALOG ((nl_catd) -1) /** * Returns true if the *unsigned* multiplication overflows. * @param a The first operand. * @param b The second operand. * @param r The product. * @return True if the multiplication of @a a and @a b overflows. */ #define BC_VM_MUL_OVERFLOW(a, b, r) \ ((r) >= SIZE_MAX || ((a) != 0 && (r) / (a) != (b))) /// The global vm struct. This holds all of the global data besides the file /// buffers. typedef struct BcVm { /// The current status. This is volatile sig_atomic_t because it is also /// used in the signal handler. See the development manual /// (manuals/development.md#async-signal-safe-signal-handling) for more /// information. volatile sig_atomic_t status; /// Non-zero if a jump series is in progress and items should be popped off /// the jmp_bufs vector. This is volatile sig_atomic_t because it is also /// used in the signal handler. See the development manual /// (manuals/development.md#async-signal-safe-signal-handling) for more /// information. volatile sig_atomic_t sig_pop; #if !BC_ENABLE_LIBRARY /// The parser. BcParse prs; /// The program. BcProgram prog; /// A buffer for lines for stdin. BcVec line_buf; /// A buffer to hold a series of lines from stdin. Sometimes, multiple lines /// are necessary for parsing, such as a comment that spans multiple lines. BcVec buffer; /// A parser to parse read expressions. BcParse read_prs; /// A buffer for read expressions. BcVec read_buf; #endif // !BC_ENABLE_LIBRARY /// A vector of jmp_bufs for doing a jump series. This allows exception-type /// error handling, while allowing me to do cleanup on the way. BcVec jmp_bufs; /// The number of temps in the temps array. size_t temps_len; #if BC_ENABLE_LIBRARY /// The vector of contexts for the library. BcVec ctxts; /// The vector for creating strings to pass to the client. BcVec out; /// The PRNG. BcRNG rng; /// The current error. BclError err; /// Whether or not bcl should abort on fatal errors. bool abrt; /// Whether or not to print leading zeros. bool leading_zeroes; /// The number of "references," or times that the library was initialized. unsigned int refs; /// Non-zero if bcl is running. This is volatile sig_atomic_t because it is /// also used in the signal handler. See the development manual /// (manuals/development.md#async-signal-safe-signal-handling) for more /// information. volatile sig_atomic_t running; #endif // BC_ENABLE_LIBRARY #if !BC_ENABLE_LIBRARY /// A pointer to the filename of the current file. This is not owned by the /// BcVm struct. const char* file; /// The message printed when SIGINT happens. const char *sigmsg; #endif // !BC_ENABLE_LIBRARY /// Non-zero when signals are "locked." This is volatile sig_atomic_t /// because it is also used in the signal handler. See the development /// manual (manuals/development.md#async-signal-safe-signal-handling) for /// more information. volatile sig_atomic_t sig_lock; /// Non-zero when a signal has been received, but not acted on. This is /// volatile sig_atomic_t because it is also used in the signal handler. See /// the development manual /// (manuals/development.md#async-signal-safe-signal-handling) for more /// information. volatile sig_atomic_t sig; #if !BC_ENABLE_LIBRARY /// The length of sigmsg. uchar siglen; /// The instruction used for returning from a read() call. uchar read_ret; /// The flags field used by most macros above. uint16_t flags; /// The number of characters printed in the current line. This is used /// because bc has a limit of the number of characters it can print per /// line. uint16_t nchars; /// The length of the line we can print. The user can set this if they wish. uint16_t line_len; /// True if bc should error if expressions are encountered during option /// parsing, false otherwise. bool no_exprs; /// True if bc should exit if expresions are encountered. bool exit_exprs; /// True if EOF was encountered. bool eof; /// True if bc is currently reading from stdin. bool is_stdin; #if BC_ENABLED /// True if keywords should not be redefined. This is only true for the /// builtin math libraries for bc. bool no_redefine; #endif // BC_ENABLED #endif // !BC_ENABLE_LIBRARY /// An array of maxes for the globals. BcBigDig maxes[BC_PROG_GLOBALS_LEN + BC_ENABLE_EXTRA_MATH]; #if !BC_ENABLE_LIBRARY /// A vector of filenames to process. BcVec files; /// A vector of expressions to process. BcVec exprs; /// The name of the calculator under use. This is used by BC_IS_BC and /// BC_IS_DC. const char *name; /// The help text for the calculator. const char *help; #if BC_ENABLE_HISTORY /// The history data. BcHistory history; #endif // BC_ENABLE_HISTORY /// The function to call to get the next lex token. BcLexNext next; /// The function to call to parse. BcParseParse parse; /// The function to call to parse expressions. BcParseExpr expr; /// The text to display to label functions in error messages. const char *func_header; /// The names of the categories of errors. const char *err_ids[BC_ERR_IDX_NELEMS + BC_ENABLED]; /// The messages for each error. const char *err_msgs[BC_ERR_NELEMS]; /// The locale. const char *locale; #endif // !BC_ENABLE_LIBRARY /// The last base used to parse. BcBigDig last_base; /// The last power of last_base used to parse. BcBigDig last_pow; /// The last exponent of base that equals last_pow. BcBigDig last_exp; /// BC_BASE_POW - last_pow. BcBigDig last_rem; #if !BC_ENABLE_LIBRARY /// A buffer of environment arguments. This is the actual value of the /// environment variable. char *env_args_buffer; /// A vector for environment arguments after parsing. BcVec env_args; /// A BcNum set to constant 0. BcNum zero; #endif // !BC_ENABLE_LIBRARY /// A BcNum set to constant 1. BcNum one; /// A BcNum holding the max number held by a BcBigDig plus 1. BcNum max; /// A BcNum holding the max number held by a BcBigDig times 2 plus 1. BcNum max2; /// The BcDig array for max. BcDig max_num[BC_NUM_BIGDIG_LOG10]; /// The BcDig array for max2. BcDig max2_num[BC_NUM_BIGDIG_LOG10]; // The BcDig array for the one BcNum. BcDig one_num[BC_VM_ONE_CAP]; #if !BC_ENABLE_LIBRARY // The BcDig array for the zero BcNum. BcDig zero_num[BC_VM_ONE_CAP]; /// The stdout file. BcFile fout; /// The stderr file. BcFile ferr; #if BC_ENABLE_NLS /// The locale catalog. nl_catd catalog; #endif // BC_ENABLE_NLS /// A pointer to the stdin buffer. char *buf; /// The number of items in the input buffer. size_t buf_len; /// The slab for constants in the main function. This is separate for /// garbage collection reasons. BcVec main_const_slab; //// The slab for all other strings for the main function. BcVec main_slabs; /// The slab for function names, strings in other functions, and constants /// in other functions. BcVec other_slabs; #if BC_ENABLED /// An array of booleans for which bc keywords have been redefined if /// BC_REDEFINE_KEYWORDS is non-zero. bool redefined_kws[BC_LEX_NKWS]; #endif // BC_ENABLED #endif // !BC_ENABLE_LIBRARY #if BC_DEBUG_CODE /// The depth for BC_FUNC_ENTER and BC_FUNC_EXIT. size_t func_depth; #endif // BC_DEBUG_CODE } BcVm; /** * Print the copyright banner and help if it's non-NULL. * @param help The help message to print if it's non-NULL. */ void bc_vm_info(const char* const help); /** * The entrance point for bc/dc together. * @param argc The count of arguments. * @param argv The argument array. */ void bc_vm_boot(int argc, char *argv[]); /** * Initializes some of the BcVm global. This is separate to make things easier * on the library code. */ void bc_vm_init(void); /** * Frees the BcVm global. */ void bc_vm_shutdown(void); /** * Add a temp to the temp array. * @param num The BcDig array to add to the temp array. */ void bc_vm_addTemp(BcDig *num); /** * Dish out a temp, or NULL if there are none. * @return A temp, or NULL if none exist. */ BcDig* bc_vm_takeTemp(void); /** * Frees all temporaries. */ void bc_vm_freeTemps(void); #if !BC_ENABLE_HISTORY /** * Erases the flush argument if history does not exist because it does not * matter if history does not exist. */ #define bc_vm_putchar(c, t) bc_vm_putchar(c) #endif // !BC_ENABLE_HISTORY /** * Print to stdout with limited formating. * @param fmt The format string. */ void bc_vm_printf(const char *fmt, ...); /** * Puts a char into the stdout buffer. * @param c The character to put on the stdout buffer. * @param type The flush type. */ void bc_vm_putchar(int c, BcFlushType type); /** * Multiplies @a n and @a size and throws an allocation error if overflow * occurs. * @param n The number of elements. * @param size The size of each element. * @return The product of @a n and @a size. */ size_t bc_vm_arraySize(size_t n, size_t size); /** * Adds @a a and @a b and throws an error if overflow occurs. * @param a The first operand. * @param b The second operand. * @return The sum of @a a and @a b. */ size_t bc_vm_growSize(size_t a, size_t b); /** * Allocate @a n bytes and throw an allocation error if allocation fails. * @param n The bytes to allocate. * @return A pointer to the allocated memory. */ void* bc_vm_malloc(size_t n); /** * Reallocate @a ptr to be @a n bytes and throw an allocation error if * reallocation fails. * @param ptr The pointer to a memory allocation to reallocate. * @param n The bytes to allocate. * @return A pointer to the reallocated memory. */ void* bc_vm_realloc(void *ptr, size_t n); /** * Allocates space for, and duplicates, @a str. * @param str The string to allocate. * @return The allocated string. */ char* bc_vm_strdup(const char *str); /** * Reads a line into BcVm's buffer field. * @param clear True if the buffer should be cleared first, false otherwise. * @return True if a line was read, false otherwise. */ bool bc_vm_readLine(bool clear); /** * A convenience and portability function for OpenBSD's pledge(). * @param promises The promises to pledge(). * @param execpromises The exec promises to pledge(). */ void bc_pledge(const char *promises, const char *execpromises); /** * Returns the value of an environment variable. * @param var The environment variable. * @return The value of the environment variable. */ char* bc_vm_getenv(const char* var); /** * Frees an environment variable value. * @param val The value to free. */ void bc_vm_getenvFree(char* val); #if BC_DEBUG_CODE /** * Start executing a jump series. * @param f The name of the function that started the jump series. */ void bc_vm_jmp(const char *f); #else // BC_DEBUG_CODE /** * Start executing a jump series. */ void bc_vm_jmp(void); #endif // BC_DEBUG_CODE #if BC_ENABLE_LIBRARY /** * Handle an error. This is the true error handler. It will start a jump series * if an error occurred. POSIX errors will not cause jumps when warnings are on * or no POSIX errors are enabled. * @param e The error. */ void bc_vm_handleError(BcErr e); /** * Handle a fatal error. * @param e The error. */ void bc_vm_fatalError(BcErr e); /** * A function to call at exit. */ void bc_vm_atexit(void); #else // BC_ENABLE_LIBRARY /** * Handle an error. This is the true error handler. It will start a jump series * if an error occurred. POSIX errors will not cause jumps when warnings are on * or no POSIX errors are enabled. * @param e The error. * @param line The source line where the error occurred. */ void bc_vm_handleError(BcErr e, size_t line, ...); /** * Handle a fatal error. * @param e The error. */ #if !BC_ENABLE_MEMCHECK BC_NORETURN #endif // !BC_ENABLE_MEMCHECK void bc_vm_fatalError(BcErr e); /** * A function to call at exit. * @param status The exit status. */ int bc_vm_atexit(int status); #endif // BC_ENABLE_LIBRARY /// A reference to the copyright header. extern const char bc_copyright[]; /// A reference to the format string for source code line printing. extern const char* const bc_err_line; /// A reference to the format string for source code function printing. extern const char* const bc_err_func_header; /// A reference to the array of default error category names. extern const char *bc_errs[]; /// A reference to the array of error category indices for each error. extern const uchar bc_err_ids[]; /// A reference to the array of default error messages. extern const char* const bc_err_msgs[]; /// A reference to the pledge() promises at start. extern const char bc_pledge_start[]; #if BC_ENABLE_HISTORY /// A reference to the end pledge() promises when using history. extern const char bc_pledge_end_history[]; #endif // BC_ENABLE_HISTORY /// A reference to the end pledge() promises when *not* using history. extern const char bc_pledge_end[]; /// A reference to the global data. extern BcVm vm; /// A reference to the global output buffers. extern char output_bufs[BC_VM_BUF_SIZE]; #endif // BC_VM_H diff --git a/contrib/bc/locales/de_DE.ISO8859-1.msg b/contrib/bc/locales/de_DE.ISO8859-1.msg index 76f2ac4190f6..dc7545e3ed72 100644 --- a/contrib/bc/locales/de_DE.ISO8859-1.msg +++ b/contrib/bc/locales/de_DE.ISO8859-1.msg @@ -1,111 +1,113 @@ $ $ $ SPDX-License-Identifier: BSD-2-Clause $ $ $ Copyright (c) 2018-2021 Gavin D. Howard and contributors. $ $ $ Redistribution and use in source and binary forms, with or without $ modification, are permitted provided that the following conditions are met: $ $ $ * Redistributions of source code must retain the above copyright notice, this $ list of conditions and the following disclaimer. $ $ $ * Redistributions in binary form must reproduce the above copyright notice, $ this list of conditions and the following disclaimer in the documentation $ and/or other materials provided with the distribution. $ $ $ THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" $ AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE $ IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE $ ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE $ LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR $ CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF $ SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS $ INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN $ CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) $ ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE $ POSSIBILITY OF SUCH DAMAGE. $ $ $quote " $ Headers for printing errors/warnings. $set 1 1 "Funktion:" $ Error types. $set 2 1 "Rechenfehler:" 2 "Analysefehler:" 3 "Laufzeitfehler:" 4 "Fataler Fehler:" 5 "Warnung:" $ Math errors. $set 3 1 "negative Zahl" 2 "Nicht-Ganzzahl-Wert" 3 "berlauf: Zahl passt nicht in Register" 4 "Division durch 0" $ Parse errors. $set 4 1 "Ende der Datei" 2 "ungltiges Zeichen: '%c'" 3 "Zeichenketten-Ende konnte nicht gefunden werden" 4 "Kommentar-Ende konnte nicht gefunden werden" 5 "ungltiges Token" 6 "ungltiger Ausdruck" 7 "leerer Ausdruck" 8 "Ungltige Druck- oder Stream-Anweisung" 9 "Ungltige Funktionsdefinition" 10 "Ungltige Zuweisung: Die linke Seite muss \"scale\", \"ibase\", \"obase\", \"seed\", \"last\", \"var\" oder \"array element\" sein" 11 "keine automatische Variable gefunden" 12 "Funktionsparameter oder Variable \"%s%s\" existiert bereits" 13 "Blockende konnte nicht gefunden werden" 14 "eine \"void-Funktion\" kann keinen Wert zurckgeben: %s()" 15 "Variable kann keine Referenz sein: %s" 16 "POSIX erlaubt keine Namen mit mehr als 1 Zeichen Lnge: %s" 17 "POSIX erlaubt keine '#'-Skriptkommentare" 18 "POSIX erlaubt das Schlsselwort \"%s\" nicht" 19 "POSIX erlaubt keinen Punkt ('.') als Abkrzung fr das letzte Ergebnis" 20 "POSIX bentigt Klammern um Rckgabeausdrcke" 21 "POSIX erlaubt den Operator \"%s\" nicht" 22 "POSIX erlaubt keine Vergleichsoperatoren auerhalb von if-Anweisungen oder Schleifen" 23 "POSIX bentigt 0 oder 1 Vergleichsoperatoren pro Bedingung" 24 "POSIX erlaubt keinen leeren Ausdruck in einer for-Schleife" -25 "POSIX erlaubt keine exponentielle Notation" -26 "POSIX erlaubt keine Feld-Referenzen als Funktionsparameter" -27 "POSIX erfordert, dass die linke Klammer auf der gleichen Linie wie der Funktionskopf steht" -28 "POSIX erlaubt keine Zuweisung von Strings an Variablen oder Arrays" +25 "POSIX verlangt einen Zeilenumbruch zwischen einem Semikolon und einer Funktionsdefinition" +26 "POSIX erlaubt keine exponentielle Notation" +27 "POSIX erlaubt keine Feld-Referenzen als Funktionsparameter" +28 "POSIX erlaubt keine ungltigen Funktionen" +29 "POSIX erfordert, dass die linke Klammer auf der gleichen Linie wie der Funktionskopf steht" +30 "POSIX erlaubt keine Zuweisung von Strings an Variablen oder Arrays" $ Runtime errors. $set 5 1 "ungltige \"ibase\": muss im Intervall [%lu, %lu] liegen" 2 "ungltige \"obase\": muss im Intervall [%lu, %lu] liegen" 3 "ungltige \"scale\": muss im Intervall [%lu, %lu] liegen" 4 "ungltiger read()-Ausdruck" 5 "rekursiver read()-Aufruf" 6 "Variable oder Feld-Element hat den falschen Typ" 7 "Stapel hat zu wenig Elemente" 8 "Stapel fr Register \"%s\" hat zu wenig Elemente" 9 "falsche Anzahl der Parameter: bentigt %zu, hat %zu" 10 "undefinierte Funktion: %s()" 11 "kann keinen ungltigen Wert in einem Ausdruck verwenden" $ Fatal errors. $set 6 1 "Speicherzuweisung fehlgeschlagen" 2 "Ein-Ausgabe-Fehler" 3 "konnte die Datei nicht ffnen: %s" 4 "Datei ist nicht Text: %s" 5 "Pfad ist ein Verzeichnis: %s" 6 "ungltige Befehlszeilenoption: \"%s\"" 7 "Option erfordert ein Argument: '%c' (\"%s\")" 8 "Option benutzt keine Argumente: '%c' (\"%s\")" 9 "ungltiges Argument der Befehlszeilenoption: \"%s\"" diff --git a/contrib/bc/locales/de_DE.UTF-8.msg b/contrib/bc/locales/de_DE.UTF-8.msg index c4dad4cd3a60..7956615e849f 100644 --- a/contrib/bc/locales/de_DE.UTF-8.msg +++ b/contrib/bc/locales/de_DE.UTF-8.msg @@ -1,111 +1,113 @@ $ $ $ SPDX-License-Identifier: BSD-2-Clause $ $ $ Copyright (c) 2018-2021 Gavin D. Howard and contributors. $ $ $ Redistribution and use in source and binary forms, with or without $ modification, are permitted provided that the following conditions are met: $ $ $ * Redistributions of source code must retain the above copyright notice, this $ list of conditions and the following disclaimer. $ $ $ * Redistributions in binary form must reproduce the above copyright notice, $ this list of conditions and the following disclaimer in the documentation $ and/or other materials provided with the distribution. $ $ $ THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" $ AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE $ IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE $ ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE $ LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR $ CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF $ SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS $ INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN $ CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) $ ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE $ POSSIBILITY OF SUCH DAMAGE. $ $ $quote " $ Headers for printing errors/warnings. $set 1 1 "Funktion:" $ Error types. $set 2 1 "Rechenfehler:" 2 "Analysefehler:" 3 "Laufzeitfehler:" 4 "Fataler Fehler:" 5 "Warnung:" $ Math errors. $set 3 1 "negative Zahl" 2 "Nicht-Ganzzahl-Wert" 3 "Überlauf: Zahl passt nicht in Register" 4 "Division durch 0" $ Parse errors. $set 4 1 "Ende der Datei" 2 "ungültiges Zeichen: '%c'" 3 "Zeichenketten-Ende konnte nicht gefunden werden" 4 "Kommentar-Ende konnte nicht gefunden werden" 5 "ungültiges Token" 6 "ungültiger Ausdruck" 7 "leerer Ausdruck" 8 "Ungültige Druck- oder Stream-Anweisung" 9 "Ungültige Funktionsdefinition" 10 "Ungültige Zuweisung: Die linke Seite muss \"scale\", \"ibase\", \"obase\", \"seed\", \"last\", \"var\" oder \"array element\" sein" 11 "keine automatische Variable gefunden" 12 "Funktionsparameter oder Variable \"%s%s\" existiert bereits" 13 "Blockende konnte nicht gefunden werden" 14 "eine \"void-Funktion\" kann keinen Wert zurückgeben: %s()" 15 "Variable kann keine Referenz sein: %s" 16 "POSIX erlaubt keine Namen mit mehr als 1 Zeichen Länge: %s" 17 "POSIX erlaubt keine '#'-Skriptkommentare" 18 "POSIX erlaubt das Schlüsselwort \"%s\" nicht" 19 "POSIX erlaubt keinen Punkt ('.') als Abkürzung für das letzte Ergebnis" 20 "POSIX benötigt Klammern um Rückgabeausdrücke" 21 "POSIX erlaubt den Operator \"%s\" nicht" 22 "POSIX erlaubt keine Vergleichsoperatoren außerhalb von if-Anweisungen oder Schleifen" 23 "POSIX benötigt 0 oder 1 Vergleichsoperatoren pro Bedingung" 24 "POSIX erlaubt keinen leeren Ausdruck in einer for-Schleife" -25 "POSIX erlaubt keine exponentielle Notation" -26 "POSIX erlaubt keine Feld-Referenzen als Funktionsparameter" -27 "POSIX erfordert, dass die linke Klammer auf der gleichen Linie wie der Funktionskopf steht" -28 "POSIX erlaubt keine Zuweisung von Strings an Variablen oder Arrays" +25 "POSIX verlangt einen Zeilenumbruch zwischen einem Semikolon und einer Funktionsdefinition" +26 "POSIX erlaubt keine exponentielle Notation" +27 "POSIX erlaubt keine Feld-Referenzen als Funktionsparameter" +28 "POSIX erlaubt keine ungültigen Funktionen" +29 "POSIX erfordert, dass die linke Klammer auf der gleichen Linie wie der Funktionskopf steht" +30 "POSIX erlaubt keine Zuweisung von Strings an Variablen oder Arrays" $ Runtime errors. $set 5 1 "ungültige \"ibase\": muss im Intervall [%lu, %lu] liegen" 2 "ungültige \"obase\": muss im Intervall [%lu, %lu] liegen" 3 "ungültige \"scale\"; muss im Intervall [%lu, %lu] liegen" 4 "ungültiger read()-Ausdruck" 5 "rekursiver read()-Aufruf" 6 "Variable oder Feld-Element hat den falschen Typ" 7 "Stapel hat zu wenig Elemente" 8 "Stapel für Register \"%s\" hat zu wenig Elemente" 9 "falsche Anzahl der Parameter: benötigt %zu, hat %zu" 10 "undefinierte Funktion: %s()" 11 "kann keinen ungültigen Wert in einem Ausdruck verwenden" $ Fatal errors. $set 6 1 "Speicherzuweisung fehlgeschlagen" 2 "Ein-Ausgabe-Fehler" 3 "konnte die Datei nicht öffnen: %s" 4 "Datei ist nicht Text: %s" 5 "Pfad ist ein Verzeichnis: %s" 6 "ungültige Befehlszeilenoption: \"%s\"" 7 "Option erfordert ein Argument: '%c' (\"%s\")" 8 "Option benutzt keine Argumente: '%c' (\"%s\")" 9 "ungültiges Argument der Befehlszeilenoption: \"%s\"" diff --git a/contrib/bc/locales/en_US.msg b/contrib/bc/locales/en_US.msg index 707950a5767d..adc1cc4537b9 100644 --- a/contrib/bc/locales/en_US.msg +++ b/contrib/bc/locales/en_US.msg @@ -1,111 +1,113 @@ $ $ $ SPDX-License-Identifier: BSD-2-Clause $ $ $ Copyright (c) 2018-2021 Gavin D. Howard and contributors. $ $ $ Redistribution and use in source and binary forms, with or without $ modification, are permitted provided that the following conditions are met: $ $ $ * Redistributions of source code must retain the above copyright notice, this $ list of conditions and the following disclaimer. $ $ $ * Redistributions in binary form must reproduce the above copyright notice, $ this list of conditions and the following disclaimer in the documentation $ and/or other materials provided with the distribution. $ $ $ THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" $ AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE $ IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE $ ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE $ LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR $ CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF $ SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS $ INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN $ CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) $ ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE $ POSSIBILITY OF SUCH DAMAGE. $ $ $quote " $ Miscellaneous messages. $set 1 1 "Function:" $ Error types. $set 2 1 "Math error:" 2 "Parse error:" 3 "Runtime error:" 4 "Fatal error:" 5 "Warning:" $ Math errors. $set 3 1 "negative number" 2 "non-integer number" 3 "overflow: number does not fit into a hardware number" 4 "divide by 0" $ Parse errors. $set 4 1 "end of file" 2 "invalid character '%c'" 3 "string end cannot be found" 4 "comment end cannot be found" 5 "invalid token" 6 "invalid expression" 7 "empty expression" 8 "invalid print or stream statement" 9 "invalid function definition" 10 "invalid assignment: left side must be scale, ibase, obase, seed, last, var, or array element" 11 "no auto variable found" 12 "function parameter or auto \"%s%s\" already exists" 13 "block end cannot be found" 14 "cannot return a value from void function: %s()" 15 "var cannot be a reference: %s" 16 "POSIX does not allow names longer than 1 character: %s" 17 "POSIX does not allow '#' script comments" 18 "POSIX does not allow the following keyword: %s" 19 "POSIX does not allow a period ('.') as a shortcut for the last result" 20 "POSIX requires parentheses around return expressions" 21 "POSIX does not allow the following operator: %s" 22 "POSIX does not allow comparison operators outside if statements or loops" 23 "POSIX requires 0 or 1 comparison operators per condition" 24 "POSIX requires all 3 parts of a for loop to be non-empty" -25 "POSIX does not allow exponential notation" -26 "POSIX does not allow array references as function parameters" -27 "POSIX requires the left brace be on the same line as the function header" -28 "POSIX does not allow strings to be assigned to variables or arrays" +25 "POSIX requires a newline between a semicolon and a function definition", +26 "POSIX does not allow exponential notation" +27 "POSIX does not allow array references as function parameters" +28 "POSIX does not allow void functions", +29 "POSIX requires the left brace be on the same line as the function header" +30 "POSIX does not allow strings to be assigned to variables or arrays" $ Runtime errors. $set 5 1 "invalid ibase: must be [%lu, %lu]" 2 "invalid obase: must be [%lu, %lu]" 3 "invalid scale: must be [%lu, %lu]" 4 "invalid read() expression" 5 "recursive read() call" 6 "variable or array element is the wrong type" 7 "stack has too few elements" 8 "stack for register \"%s\" has too few elements" 9 "wrong number of parameters; need %zu, have %zu" 10 "undefined function: %s()" 11 "cannot use a void value in an expression" $ Fatal errors. $set 6 1 "memory allocation failed" 2 "I/O error" 3 "cannot open file: %s" 4 "file is not text: %s" 5 "path is a directory: %s" 6 "invalid command-line option: \"%s\"" 7 "option requires an argument: '%c' (\"%s\")" 8 "option takes no arguments: '%c' (\"%s\")" 9 "invalid command-line option argument: \"%s\"" diff --git a/contrib/bc/locales/es_ES.ISO8859-1.msg b/contrib/bc/locales/es_ES.ISO8859-1.msg index 8d74f884f811..30c965111de6 100644 --- a/contrib/bc/locales/es_ES.ISO8859-1.msg +++ b/contrib/bc/locales/es_ES.ISO8859-1.msg @@ -1,111 +1,113 @@ $ $ $ SPDX-License-Identifier: BSD-2-Clause $ $ $ Copyright (c) 2018-2021 Gavin D. Howard and contributors. $ $ $ Redistribution and use in source and binary forms, with or without $ modification, are permitted provided that the following conditions are met: $ $ $ * Redistributions of source code must retain the above copyright notice, this $ list of conditions and the following disclaimer. $ $ $ * Redistributions in binary form must reproduce the above copyright notice, $ this list of conditions and the following disclaimer in the documentation $ and/or other materials provided with the distribution. $ $ $ THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" $ AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE $ IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE $ ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE $ LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR $ CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF $ SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS $ INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN $ CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) $ ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE $ POSSIBILITY OF SUCH DAMAGE. $ $ $quote " $ Miscellaneous messages. $set 1 1 "Funcin:" $ Error types. $set 2 1 "Error de matemtica:" 2 "Error de syntaxis:" 3 "Error de ejecucin:" 4 "Error fatal:" 5 "Advertencia:" $ Math errors. $set 3 1 "nmero negativo" 2 "nmero no es entero" 3 "desbordamiento de enteros: no se puede encajar el el hardware" 4 "divisin por cero" $ Parse errors. $set 4 1 "fin de archivo" 2 "no vlido '%c'" 3 "no puede encontrar el fine de la cadena" 4 "no puede encontrar el fine del comentario" 5 "el token no es vlido" 6 "la expresin no es vlida" 7 "la expresin es vaca" 8 "la expresin de print o de stream no es vlida" 9 "la definicin de funcin no es vlida" 10 "la asignacin no es valida: en la izquierda debe ser scale, ibase, obase, last, var, o un elemento de matriz" 11 "no se encontr ninguna variable automtica" 12 "ya hay un parmetro de funcin o variable automatica que se llama \"%s%s\"" 13 "no se puede encontrar el final de del bloque de cdigo" 14 "no puede haber un valor de retorno de una funcin \"void\": %s()" 15 "var no puede ser una referencia: %s" 16 "POSIX no permite nombres de ms de 1 carcter: %s" 17 "POSIX no permite '#' script comentarios" 18 "POSIX no permite este palabra clave %s" 19 "POSIX no permite un punto ('.') como un atajo del resultado previoso" 20 "POSIX requieres parntesis en el expresin del \"return\"" 21 "POSIX no permite este operador: %s" 22 "POSIX no permite operadores de comparacin aparte de \"if\" expresin o bucles" 23 "POSIX requiere 0 o 1 operadores de comparisn para cada condicin" 24 "POSIX requiere todos 3 partes de una bucla que no esta vaco" -25 "POSIX no permite una notacin exponencial" -26 "POSIX no permite una referencia a una matriz como un parmetro de funcin" -27 "POSIX requiere el llave de la izquierda que sea en la misma lnea que los parmetros de la funcin" -28 "POSIX no permite asignar cadenas a variables o matrices" +25 "POSIX requiere una nueva lnea entre un punto y coma y una definicin de funcin" +26 "POSIX no permite una notacin exponencial" +27 "POSIX no permite una referencia a una matriz como un parmetro de funcin" +28 "POSIX no permite funciones void" +29 "POSIX requiere el llave de la izquierda que sea en la misma lnea que los parmetros de la funcin" +30 "POSIX no permite asignar cadenas a variables o matrices" $ Runtime errors. $set 5 1 "\"ibase\" no es vlido: debe ser [%lu, %lu]" 2 "\"obase\" no es vlido: debe ser [%lu, %lu]" 3 "\"scale\" no es vlido: debe ser [%lu, %lu]" 4 "read() expresin no es vlido" 5 "recursion en la invocacin de read()" 6 "variable o elemento del matriz de tipo equivocado" 7 "la pila no ha demaciado elementos" 8 "la pila del registro \"%s\" no ha demaciado elementos" 9 "la funcin no tiene un nmero de argumentos correcto; necessita %zu, tiene %zu" 10 "la funcin no esta definida: %s()" 11 "no puede utilizar un valor vaco en una expresin" $ Fatal errors. $set 6 1 "error en la asignacin de memoria" 2 "error de I/O" 3 "no puede abrir el archivo: %s" 4 "el archivo no es texto: %s" 5 "el ruta es un directorio: %s" 6 "una opcin de lnea de comandos no es vlida: \"%s\"" 7 "una opcin requiere un argumento: '%c' (\"%s\")" 8 "una opcin no tiene argumento: '%c' (\"%s\")" 9 "uno argumento de opcin de lnea de comandos no es vlido: \"%s\"" diff --git a/contrib/bc/locales/es_ES.UTF-8.msg b/contrib/bc/locales/es_ES.UTF-8.msg index 26559e6e9b88..1721dd3d8f2a 100644 --- a/contrib/bc/locales/es_ES.UTF-8.msg +++ b/contrib/bc/locales/es_ES.UTF-8.msg @@ -1,111 +1,113 @@ $ $ $ SPDX-License-Identifier: BSD-2-Clause $ $ $ Copyright (c) 2018-2021 Gavin D. Howard and contributors. $ $ $ Redistribution and use in source and binary forms, with or without $ modification, are permitted provided that the following conditions are met: $ $ $ * Redistributions of source code must retain the above copyright notice, this $ list of conditions and the following disclaimer. $ $ $ * Redistributions in binary form must reproduce the above copyright notice, $ this list of conditions and the following disclaimer in the documentation $ and/or other materials provided with the distribution. $ $ $ THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" $ AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE $ IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE $ ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE $ LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR $ CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF $ SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS $ INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN $ CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) $ ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE $ POSSIBILITY OF SUCH DAMAGE. $ $ $quote " $ Miscellaneous messages. $set 1 1 "Función:" $ Error types. $set 2 1 "Error de matemática:" 2 "Error de syntaxis:" 3 "Error de ejecución:" 4 "Error fatal:" 5 "Advertencia:" $ Math errors. $set 3 1 "número negativo" 2 "número no es entero" 3 "desbordamiento de enteros: no se puede encajar el el hardware" 4 "división por cero" $ Parse errors. $set 4 1 "fin de archivo" 2 "no válido '%c'" 3 "no puede encontrar el fine de la cadena" 4 "no puede encontrar el fine del comentario" 5 "el token no es válido" 6 "la expresión no es válida" 7 "la expresión es vacía" 8 "la expresión de print o de stream no es válida" 9 "la definición de función no es válida" 10 "la asignación no es valida: en la izquierda debe ser scale, ibase, obase, last, var, o un elemento de matriz" 11 "no se encontró ninguna variable automática" 12 "ya hay un parámetro de función o variable automatica que se llama \"%s%s\"" 13 "no se puede encontrar el final de del bloque de código" 14 "no puede haber un valor de retorno de una función \"void\": %s()" 15 "var no puede ser una referencia: %s" 16 "POSIX no permite nombres de más de 1 carácter: %s" 17 "POSIX no permite '#' script comentarios" 18 "POSIX no permite este palabra clave %s" 19 "POSIX no permite un punto ('.') como un atajo del resultado previoso" 20 "POSIX requieres paréntesis en el expresión del \"return\"" 21 "POSIX no permite este operador: %s" 22 "POSIX no permite operadores de comparación aparte de \"if\" expresión o bucles" 23 "POSIX requiere 0 o 1 operadores de comparisón para cada condición" 24 "POSIX requiere todos 3 partes de una bucla que no esta vacío" -25 "POSIX no permite una notación exponencial" -26 "POSIX no permite una referencia a una matriz como un parámetro de función" -27 "POSIX requiere el llave de la izquierda que sea en la misma línea que los parámetros de la función" -28 "POSIX no permite asignar cadenas a variables o matrices" +25 "POSIX requiere una nueva línea entre un punto y coma y una definición de función" +26 "POSIX no permite una notación exponencial" +27 "POSIX no permite una referencia a una matriz como un parámetro de función" +28 "POSIX no permite funciones void" +29 "POSIX requiere el llave de la izquierda que sea en la misma línea que los parámetros de la función" +30 "POSIX no permite asignar cadenas a variables o matrices" $ Runtime errors. $set 5 1 "\"ibase\" no es válido: debe ser [%lu, %lu]" 2 "\"obase\" no es válido: debe ser [%lu, %lu]" 3 "\"scale\" no es válido: debe ser [%lu, %lu]" 4 "read() expresión no es válido" 5 "recursion en la invocación de read()" 6 "variable o elemento del matriz de tipo equivocado" 7 "la pila no ha demaciado elementos" 8 "la pila del registro \"%s\" no ha demaciado elementos" 9 "la función no tiene un número de argumentos correcto; necessita %zu, tiene %zu" 10 "la función no esta definida: %s()" 11 "no puede utilizar un valor vacío en una expresión" $ Fatal errors. $set 6 1 "error en la asignación de memoria" 2 "error de I/O" 3 "no puede abrir el archivo: %s" 4 "el archivo no es texto: %s" 5 "el ruta es un directorio: %s" 6 "una opción de línea de comandos no es válida: \"%s\"" 7 "una opción requiere un argumento: '%c' (\"%s\")" 8 "una opción no tiene argumento: '%c' (\"%s\")" 9 "uno argumento de opción de línea de comandos no es válido: \"%s\"" diff --git a/contrib/bc/locales/fr_FR.ISO8859-1.msg b/contrib/bc/locales/fr_FR.ISO8859-1.msg index 8e894e043bbc..5d772abcc4ef 100644 --- a/contrib/bc/locales/fr_FR.ISO8859-1.msg +++ b/contrib/bc/locales/fr_FR.ISO8859-1.msg @@ -1,111 +1,113 @@ $ $ $ SPDX-License-Identifier: BSD-2-Clause $ $ $ Copyright (c) 2018-2021 Gavin D. Howard and contributors. $ $ $ Redistribution and use in source and binary forms, with or without $ modification, are permitted provided that the following conditions are met: $ $ $ * Redistributions of source code must retain the above copyright notice, this $ list of conditions and the following disclaimer. $ $ $ * Redistributions in binary form must reproduce the above copyright notice, $ this list of conditions and the following disclaimer in the documentation $ and/or other materials provided with the distribution. $ $ $ THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" $ AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE $ IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE $ ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE $ LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR $ CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF $ SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS $ INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN $ CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) $ ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE $ POSSIBILITY OF SUCH DAMAGE. $ $ $quote " $ Miscellaneous messages. $set 1 1 "Fonction :" $ Error types. $set 2 1 "Erreur de calcul :" 2 "Erreur d'analyse syntaxique :" 3 "Erreur d'exécution :" 4 "Erreur fatale :" 5 "Avertissement :" $ Math errors. $set 3 1 "nombre strictement négatif" 2 "nombre non entier" 3 "dépassement : le nombre ne tient pas dans un type traité par le processeur" 4 "division par 0" $ Parse errors. $set 4 1 "fin de fichier" 2 "caractère invalide '%c'" 3 "fin de chaîne non trouvée" 4 "fin de commentaire non trouvée" 5 "symbole invalide" 6 "expression invalide" 7 "expression vide" 8 "instruction d'écriture ou de flux invalide" 9 "définition de fonction invalide" 10 "affectation invalide : la partie gauche doit être 'scale', 'ibase', 'obase', 'seed', 'last', une variable ou une case de tableau" 11 "aucune variable auto trouvée" 12 "Le paramètre de fonction ou variable auto \"%s%s\" existe déjà" 13 "fin de bloc non trouvée" 14 "une fonction 'void' ne peut pas retourner de valeur : %s()" 15 "Une variable ne peut pas être une référence : %s" 16 "POSIX interdit les noms de plus d'un caractère : %s" 17 "POSIX interdit les commentaires dans les scripts (pas de '#')" 18 "POSIX interdit le mot-clé '%s'" 19 "POSIX interdit l'utilisation du point ('.') comme raccourci pour le dernier résultat" 20 "POSIX impose des parenthèses autour des expressions de retour" 21 "POSIX interdit l'opérateur '%s'" 22 "POSIX interdit les opérateurs de comparaison en dehors des expressions 'if' ou des boucles" 23 "POSIX impose 0 ou 1 opérateur de comparaison par condition" 24 "POSIX interdit une expression vide dans une boucle 'for'" -25 "POSIX interdit la notation exponentielle" -26 "POSIX interdit les références à un tableau dans les paramètres d'une fonction" -27 "POSIX impose que l'en-tête de la fonction et le '{' soient sur la même ligne" -28 "POSIX interdit pas d'assigner des chaînes de caractères à des variables ou à des tableaux" +25 "POSIX exige une nouvelle ligne entre un point-virgule et une définition de fonction" +26 "POSIX interdit la notation exponentielle" +27 "POSIX interdit les références à un tableau dans les paramètres d'une fonction" +28 "POSIX n'autorise pas les fonctions void" +29 "POSIX impose que l'en-tête de la fonction et le '{' soient sur la même ligne" +30 "POSIX interdit pas d'assigner des chaînes de caractères à des variables ou à des tableaux" $ Runtime errors. $set 5 1 "ibase invalide : doit être [%lu, %lu]" 2 "obase invalide : doit être [%lu, %lu]" 3 "scale invalide : doit être [%lu, %lu]" 4 "expression read() invalide" 5 "appel read() récursif" 6 "mauvais type de variable ou d'élément de tableau" 7 "pile sous-remplie" 8 "pile pour le registre \"%s\" sous-remplie" 9 "nombre incorrect de paramètres - attendus : %zu, obtenus : %zu" 10 "fonction non définie : %s()" 11 "une valeur 'void' est inutilisable dans une expression" $ Fatal errors. $set 6 1 "échec d'allocation mémoire" 2 "erreur d'entrée-sortie" 3 "impossible d'ouvrir le fichier : %s" 4 "fichier non texte: %s" 5 "le chemin est un répertoire : %s" 6 "option de ligne de commande invalide : \"%s\"" 7 "l'option '%c' (\"%s\") requiert un argument" 8 "l'option '%c' (\"%s\") ne prend pas d'argument" 9 "argument d'option de ligne de commande invalide : \"%s\"" diff --git a/contrib/bc/locales/fr_FR.UTF-8.msg b/contrib/bc/locales/fr_FR.UTF-8.msg index 8e894e043bbc..6393ab0e5f70 100644 --- a/contrib/bc/locales/fr_FR.UTF-8.msg +++ b/contrib/bc/locales/fr_FR.UTF-8.msg @@ -1,111 +1,113 @@ $ $ $ SPDX-License-Identifier: BSD-2-Clause $ $ $ Copyright (c) 2018-2021 Gavin D. Howard and contributors. $ $ $ Redistribution and use in source and binary forms, with or without $ modification, are permitted provided that the following conditions are met: $ $ $ * Redistributions of source code must retain the above copyright notice, this $ list of conditions and the following disclaimer. $ $ $ * Redistributions in binary form must reproduce the above copyright notice, $ this list of conditions and the following disclaimer in the documentation $ and/or other materials provided with the distribution. $ $ $ THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" $ AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE $ IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE $ ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE $ LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR $ CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF $ SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS $ INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN $ CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) $ ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE $ POSSIBILITY OF SUCH DAMAGE. $ $ $quote " $ Miscellaneous messages. $set 1 1 "Fonction :" $ Error types. $set 2 1 "Erreur de calcul :" 2 "Erreur d'analyse syntaxique :" 3 "Erreur d'exécution :" 4 "Erreur fatale :" 5 "Avertissement :" $ Math errors. $set 3 1 "nombre strictement négatif" 2 "nombre non entier" 3 "dépassement : le nombre ne tient pas dans un type traité par le processeur" 4 "division par 0" $ Parse errors. $set 4 1 "fin de fichier" 2 "caractère invalide '%c'" 3 "fin de chaîne non trouvée" 4 "fin de commentaire non trouvée" 5 "symbole invalide" 6 "expression invalide" 7 "expression vide" 8 "instruction d'écriture ou de flux invalide" 9 "définition de fonction invalide" 10 "affectation invalide : la partie gauche doit être 'scale', 'ibase', 'obase', 'seed', 'last', une variable ou une case de tableau" 11 "aucune variable auto trouvée" 12 "Le paramètre de fonction ou variable auto \"%s%s\" existe déjà" 13 "fin de bloc non trouvée" 14 "une fonction 'void' ne peut pas retourner de valeur : %s()" 15 "Une variable ne peut pas être une référence : %s" 16 "POSIX interdit les noms de plus d'un caractère : %s" 17 "POSIX interdit les commentaires dans les scripts (pas de '#')" 18 "POSIX interdit le mot-clé '%s'" 19 "POSIX interdit l'utilisation du point ('.') comme raccourci pour le dernier résultat" 20 "POSIX impose des parenthèses autour des expressions de retour" 21 "POSIX interdit l'opérateur '%s'" 22 "POSIX interdit les opérateurs de comparaison en dehors des expressions 'if' ou des boucles" 23 "POSIX impose 0 ou 1 opérateur de comparaison par condition" 24 "POSIX interdit une expression vide dans une boucle 'for'" -25 "POSIX interdit la notation exponentielle" -26 "POSIX interdit les références à un tableau dans les paramètres d'une fonction" -27 "POSIX impose que l'en-tête de la fonction et le '{' soient sur la même ligne" -28 "POSIX interdit pas d'assigner des chaînes de caractères à des variables ou à des tableaux" +25 "POSIX exige une nouvelle ligne entre un point-virgule et une définition de fonction." +26 "POSIX interdit la notation exponentielle" +27 "POSIX interdit les références à un tableau dans les paramètres d'une fonction" +28 "POSIX n'autorise pas les fonctions void" +29 "POSIX impose que l'en-tête de la fonction et le '{' soient sur la même ligne" +30 "POSIX interdit pas d'assigner des chaînes de caractères à des variables ou à des tableaux" $ Runtime errors. $set 5 1 "ibase invalide : doit être [%lu, %lu]" 2 "obase invalide : doit être [%lu, %lu]" 3 "scale invalide : doit être [%lu, %lu]" 4 "expression read() invalide" 5 "appel read() récursif" 6 "mauvais type de variable ou d'élément de tableau" 7 "pile sous-remplie" 8 "pile pour le registre \"%s\" sous-remplie" 9 "nombre incorrect de paramètres - attendus : %zu, obtenus : %zu" 10 "fonction non définie : %s()" 11 "une valeur 'void' est inutilisable dans une expression" $ Fatal errors. $set 6 1 "échec d'allocation mémoire" 2 "erreur d'entrée-sortie" 3 "impossible d'ouvrir le fichier : %s" 4 "fichier non texte: %s" 5 "le chemin est un répertoire : %s" 6 "option de ligne de commande invalide : \"%s\"" 7 "l'option '%c' (\"%s\") requiert un argument" 8 "l'option '%c' (\"%s\") ne prend pas d'argument" 9 "argument d'option de ligne de commande invalide : \"%s\"" diff --git a/contrib/bc/locales/ja_JP.UTF-8.msg b/contrib/bc/locales/ja_JP.UTF-8.msg index 4477f2bc548b..3c51aca8194f 100644 --- a/contrib/bc/locales/ja_JP.UTF-8.msg +++ b/contrib/bc/locales/ja_JP.UTF-8.msg @@ -1,111 +1,113 @@ $ $ $ SPDX-License-Identifier: BSD-2-Clause $ $ $ Copyright (c) 2018-2021 Gavin D. Howard and contributors. $ $ $ Redistribution and use in source and binary forms, with or without $ modification, are permitted provided that the following conditions are met: $ $ $ * Redistributions of source code must retain the above copyright notice, this $ list of conditions and the following disclaimer. $ $ $ * Redistributions in binary form must reproduce the above copyright notice, $ this list of conditions and the following disclaimer in the documentation $ and/or other materials provided with the distribution. $ $ $ THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" $ AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE $ IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE $ ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE $ LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR $ CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF $ SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS $ INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN $ CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) $ ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE $ POSSIBILITY OF SUCH DAMAGE. $ $ $quote " $ その他のメッセージ。 $set 1 1 "関数：" $ エラーの種類。 $set 2 1 "数学のエラー：" 2 "パースエラー：" 3 "ランタイムエラー：" 4 "致命的なエラー：" 5 "警告：" $ 数学のエラーです。 $set 3 1 "負の数" 2 "非整数" 3 "オーバーフロー：数字がハードウェア番号に収まらない" 4 "0で割る" $ 構文解析のエラー。 $set 4 1 "ファイルの終了" 2 "無効な文字 '%c'" 3 "文字列の終端が見つかりませんでした" 4 "コメントエンドが見つかりませんでした" 5 "無効なトークン" 6 "無効な式" 7 "空の式" 8 "無効なprintまたはstream文" 9 "無効な関数定義" 10 "無効な代入：左側は scale, ibase, obase, last, var, または配列要素でなければなりません" 11 "自動変数が見つかりませんでした" 12 "関数パラメータまたは自動\"%s%s\"はすでに存在します" 13 "ブロックエンドが見つかりませんでした" 14 "void 関数から値を返すことはできません：%s()" 15 "varは参照にできません：%s" 16 "POSIX は 1 文字より長い名前を許可しません：%s" 17 "POSIX は '#' スクリプトのコメントを許可しません。" 18 "POSIX は以下のキーワードを許可しません：%s" 19 "POSIX は最後の結果のショートカットとしてピリオド ('.') を許可しません。" 20 "POSIX は戻り値式の周りに括弧を必要とします。" 21 "POSIX は次の演算子を許可しません：%s" 22 "POSIX は if 文やループの外の比較演算子を許可しません。" 23 "POSIXは条件ごとに0または1の比較演算子を必要とします。" 24 "POSIXはforループの3つの部分がすべて空でないことを要求します。" -25 "POSIXは指数表記を許可しません。" -26 "POSIX は関数パラメータとして配列参照を許可しません。" -27 "POSIXでは、関数ヘッダと同じ行に左中括弧があることが必要です。" -28 "POSIXでは、変数や配列に文字列を割り当てることはできません。" +25 "POSIXでは、セミコロンと関数定義の間に改行を入れる必要があります。" +26 "POSIXは指数表記を許可しません。" +27 "POSIX は関数パラメータとして配列参照を許可しません。" +28 "POSIXではvoid関数を認めていません。" +29 "POSIXでは、関数ヘッダと同じ行に左中括弧があることが必要です。" +30 "POSIXでは、変数や配列に文字列を割り当てることはできません。" $ ランタイムエラー。 $set 5 1 "無効なibase：は[%lu、%lu]でなければなりません" 2 "無効なobase：は[%lu、%lu]でなければなりません" 3 "無効なscale：は[%lu、%lu]でなければなりません" 4 "式が無効read()" 5 "再帰的読み込み()呼び出し" 6 "変数または配列要素の型が間違っている" 7 "スタックの要素が少なすぎる" 8 "レジスタ\"%s\"のスタックの要素が少なすぎる" 9 "パラメータの数が間違っています。" 10 "定義されていない関数：%s()" 11 "式では void 値を使用できません" $ 致命的なエラーが発生しました。 $set 6 1 "メモリの割り当てに失敗しました" 2 "I/Oエラー" 3 "ファイルを開けませんでした。%s" 4 "ファイルがテキストではない：%s" 5 "パスはディレクトリです：%s" 6 "無効なコマンドラインオプション：\"%s\"" 7 "オプションには引数が必要です：'%c' (\"%s\")" 8 "オプションは引数を取りません：'%c' (\"%s\")" 9 "無効なコマンドラインオプション引数： \"%s\" diff --git a/contrib/bc/locales/ja_JP.eucJP.msg b/contrib/bc/locales/ja_JP.eucJP.msg index a907cd7cf0e3..74bd09c27fd5 100644 --- a/contrib/bc/locales/ja_JP.eucJP.msg +++ b/contrib/bc/locales/ja_JP.eucJP.msg @@ -1,111 +1,113 @@ $ $ $ SPDX-License-Identifier: BSD-2-Clause $ $ $ Copyright (c) 2018-2021 Gavin D. Howard and contributors. $ $ $ Redistribution and use in source and binary forms, with or without $ modification, are permitted provided that the following conditions are met: $ $ $ * Redistributions of source code must retain the above copyright notice, this $ list of conditions and the following disclaimer. $ $ $ * Redistributions in binary form must reproduce the above copyright notice, $ this list of conditions and the following disclaimer in the documentation $ and/or other materials provided with the distribution. $ $ $ THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" $ AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE $ IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE $ ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE $ LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR $ CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF $ SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS $ INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN $ CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) $ ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE $ POSSIBILITY OF SUCH DAMAGE. $ $ $quote " $ ¾Υå $set 1 1 "ؿ" $ 顼μࡣ $set 2 1 "ؤΥ顼" 2 "ѡ顼" 3 "󥿥२顼" 4 "̿Ūʥ顼" 5 "ٹ" $ ؤΥ顼Ǥ $set 3 1 "ο" 2 "" 3 "Сեϡɥֹ˼ޤʤ" 4 "0dz" $ ʸϤΥ顼 $set 4 1 "եνλ" 2 "̵ʸ '%c'" 3 "ʸνüĤޤǤ" 4 "ȥɤĤޤǤ" 5 "̵ʥȡ" 6 "̵ʼ" 7 "μ" 8 "̵printޤstreamʸ" 9 "̵ʴؿ" 10 "̵¦ scale, ibase, obase, last, var, ޤǤǤʤФʤޤ" 11 "ưѿĤޤǤ" 12 "ؿѥ᡼ޤϼư\"%s%s\"ϤǤ¸ߤޤ" 13 "֥åɤĤޤǤ" 14 "void ؿ֤ͤȤϤǤޤ%s()" 15 "varϻȤˤǤޤ%s" 16 "POSIX 1 ʸĹ̾Ĥޤ%s" 17 "POSIX '#' ץȤΥȤĤޤ" 18 "POSIX ϰʲΥɤĤޤ%s" 19 "POSIX ϺǸη̤Υ硼ȥåȤȤƥԥꥪ ('.') Ĥޤ" 20 "POSIX ͼμ˳̤ɬפȤޤ" 21 "POSIX ϼα黻ҤĤޤ%s" 22 "POSIX if ʸ롼פγӱ黻ҤĤޤ" 23 "POSIXϾ老Ȥ0ޤ1ӱ黻ҤɬפȤޤ" 24 "POSIXfor롼פ3Ĥʬ٤ƶǤʤȤ׵ᤷޤ" -25 "POSIXϻؿɽĤޤ" -26 "POSIX ϴؿѥ᡼Ȥ󻲾ȤĤޤ" -27 "POSIXǤϡؿإåƱԤ˺̤뤳ȤɬפǤ" -28 "POSIXǤϡѿʸƤ뤳ȤϤǤޤ" +25 "POSIXǤϡߥȴؿδ֤˲Ԥɬפޤ" +26 "POSIXϻؿɽĤޤ" +27 "POSIX ϴؿѥ᡼Ȥ󻲾ȤĤޤ" +28 "POSIXǤvoidؿǧƤޤ" +29 "POSIXǤϡؿإåƱԤ˺̤뤳ȤɬפǤ" +30 "POSIXǤϡѿʸƤ뤳ȤϤǤޤ" $ 󥿥२顼 $set 5 1 "̵ibase[%lu%lu]ǤʤФʤޤ" 2 "̵obase[%lu%lu]ǤʤФʤޤ" 3 "̵scale[%lu%lu]ǤʤФʤޤ" 4 "̵read()" 5 "ƵŪɤ߹()ƤӽФ" 6 "ѿޤǤηְäƤ" 7 "åǤʤ" 8 "쥸\"%s\"ΥåǤʤ" 9 "ѥ᡼οְäƤޤ" 10 "Ƥʤؿ%s()" 11 "Ǥ void ͤѤǤޤ" $ ̿Ūʥ顼ȯޤ $set 6 1 "γƤ˼Ԥޤ" 2 "I/O顼" 3 "ե򳫤ޤǤ%s" 4 "ե뤬ƥȤǤϤʤ%s" 5 "ѥϥǥ쥯ȥǤ%s" 6 "̵ʥޥɥ饤󥪥ץ\"%s\"" 7 "ץˤϰɬפǤ'%c' (\"%s\")" 8 "ץϰޤ'%c' (\"%s\")" 9 "̵ʥޥɥ饤󥪥ץ \"%s\" diff --git a/contrib/bc/locales/nl_NL.ISO8859-1.msg b/contrib/bc/locales/nl_NL.ISO8859-1.msg index 76b8577108e8..2f60de23cca1 100644 --- a/contrib/bc/locales/nl_NL.ISO8859-1.msg +++ b/contrib/bc/locales/nl_NL.ISO8859-1.msg @@ -1,111 +1,113 @@ $ $ $ SPDX-License-Identifier: BSD-2-Clause $ $ $ Copyright (c) 2018-2021 Gavin D. Howard and contributors. $ $ $ Redistribution and use in source and binary forms, with or without $ modification, are permitted provided that the following conditions are met: $ $ $ * Redistributions of source code must retain the above copyright notice, this $ list of conditions and the following disclaimer. $ $ $ * Redistributions in binary form must reproduce the above copyright notice, $ this list of conditions and the following disclaimer in the documentation $ and/or other materials provided with the distribution. $ $ $ THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" $ AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE $ IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE $ ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE $ LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR $ CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF $ SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS $ INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN $ CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) $ ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE $ POSSIBILITY OF SUCH DAMAGE. $ $ $quote " $ Diversen berichten. $set 1 1 "Functie:" $ Fouttypes. $set 2 1 "Rekenfout:" 2 "Parse error:" 3 "Runtime error:" 4 "Fatale fout:" 5 "Waarschuwing:" $ Math error. $set 3 1 "negatief getal" 2 "niet-integraal getal" 3 "overloop: nummer past niet in een hardware-nummer" 4 "delen door 0" $ Parsefouten. $set 4 1 "einde van het file" 2 "ongeldig teken '%c'" 3 "string einde kon niet worden gevonden" 4 "commentaar einde kon niet worden gevonden" 5 "ongeldige token" 6 "ongeldige uitdrukking" 7 "lege uitdrukking" 8 "ongeldige print- of stream-instructie" 9 "ongeldige functiedefinitie" 10 "ongeldige toewijzing: linkerzijde moet scale, ibase, obase, last, var of array element zijn" 11 "geen autovariabele gevonden" 12 "Functieparameter of automatisch bestaat al" 13 "blokuiteinde kon niet worden gevonden" 14 "kan geen waarde uit de nietige functie teruggeven: %s()" 15 "var kan geen referentie zijn: %s" 16 "POSIX staat geen namen toe die langer zijn dan 1 teken: %s" 17 "POSIX staat geen '#'-scriptcommentaar toe" 18 "POSIX laat het volgende sleutelwoord niet toe: %s" 19 "POSIX staat geen periode ('.') toe als een kortere weg voor het laatste resultaat" 20 "POSIX vereist haakjes rond de terugkeeruitdrukkingen" 21 "POSIX laat de volgende operator niet toe: %s" 22 "POSIX laat geen vergelijking toe tussen operatoren buiten als verklaringen of lussen" 23 "POSIX vereist 0 of 1 vergelijkingsoperator per conditie" 24 "POSIX vereist dat alle 3 de delen van een lus niet leeg zijn" -25 "POSIX laat geen exponentile notatie toe" -26 "POSIX staat geen arrayreferenties toe als functieparameters" -27 "POSIX vereist dat de linkse beugel op dezelfde regel staat als de functiehoofding" -28 "POSIX staat niet toe dat strings worden toegewezen aan variabelen of arrays" +25 "POSIX vereist een nieuwe regel tussen een puntkomma en een functiedefinitie" +26 "POSIX laat geen exponentile notatie toe" +27 "POSIX staat geen arrayreferenties toe als functieparameters" +28 "POSIX staat geen lege functies toe" +29 "POSIX vereist dat de linkse beugel op dezelfde regel staat als de functiehoofding" +30 "POSIX staat niet toe dat strings worden toegewezen aan variabelen of arrays" $ Runtime fouten. $set 5 1 "ongeldige ibase: moet [%lu, %lu] zijn" 2 "ongeldige obase: moet [%lu, %lu] zijn" 3 "ongeldige schaal: moet [%lu, %lu] zijn" 4 "ongeldige read() expressie" 5 "recursieve read() call" 6 "Variabele of matrix-element is het verkeerde type" 7 "Stapel heeft te weinig elementen" 8 "Stapel voor register %s heeft te weinig elementen" 9 "Verkeerd aantal parameters; hebben %zu nodig, hebben %zu" 10 "ongedefinieerde functie: %s()" 11 "kan geen nietige waarde in een uitdrukking gebruiken" $ Fatale fouten. $set 6 1 "geheugentoewijzing mislukt" 2 "I/O-fout" 3 "kon geen file openen: %s" 4 "bestand is geen tekst: %s" 5 "pad is een directory: %s" 6 "ongeldige opdrachtregeloptie: %s" 7 "optie vereist een argument: '%c' (\"%s\")" 8 "optie neemt geen argumenten aan: '%c' (\"%s\")" 9 "ongeldige opdrachtregeloptie argument: %s" diff --git a/contrib/bc/locales/nl_NL.UTF-8.msg b/contrib/bc/locales/nl_NL.UTF-8.msg index 51acb9867e22..599628a6cc51 100644 --- a/contrib/bc/locales/nl_NL.UTF-8.msg +++ b/contrib/bc/locales/nl_NL.UTF-8.msg @@ -1,111 +1,113 @@ $ $ $ SPDX-License-Identifier: BSD-2-Clause $ $ $ Copyright (c) 2018-2021 Gavin D. Howard and contributors. $ $ $ Redistribution and use in source and binary forms, with or without $ modification, are permitted provided that the following conditions are met: $ $ $ * Redistributions of source code must retain the above copyright notice, this $ list of conditions and the following disclaimer. $ $ $ * Redistributions in binary form must reproduce the above copyright notice, $ this list of conditions and the following disclaimer in the documentation $ and/or other materials provided with the distribution. $ $ $ THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" $ AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE $ IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE $ ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE $ LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR $ CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF $ SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS $ INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN $ CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) $ ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE $ POSSIBILITY OF SUCH DAMAGE. $ $ $quote " $ Diversen berichten. $set 1 1 "Functie:" $ Fouttypes. $set 2 1 "Rekenfout:" 2 "Parse error:" 3 "Runtime error:" 4 "Fatale fout:" 5 "Waarschuwing:" $ Math error. $set 3 1 "negatief getal" 2 "niet-integraal getal" 3 "overloop: nummer past niet in een hardware-nummer" 4 "delen door 0" $ Parsefouten. $set 4 1 "einde van het file" 2 "ongeldig teken '%c'" 3 "string einde kon niet worden gevonden" 4 "commentaar einde kon niet worden gevonden" 5 "ongeldige token" 6 "ongeldige uitdrukking" 7 "lege uitdrukking" 8 "ongeldige print- of stream-instructie" 9 "ongeldige functiedefinitie" 10 "ongeldige toewijzing: linkerzijde moet scale, ibase, obase, last, var of array element zijn" 11 "geen autovariabele gevonden" 12 "Functieparameter of automatisch bestaat al" 13 "blokuiteinde kon niet worden gevonden" 14 "kan geen waarde uit de nietige functie teruggeven: %s()" 15 "var kan geen referentie zijn: %s" 16 "POSIX staat geen namen toe die langer zijn dan 1 teken: %s" 17 "POSIX staat geen '#'-scriptcommentaar toe" 18 "POSIX laat het volgende sleutelwoord niet toe: %s" 19 "POSIX staat geen periode ('.') toe als een kortere weg voor het laatste resultaat" 20 "POSIX vereist haakjes rond de terugkeeruitdrukkingen" 21 "POSIX laat de volgende operator niet toe: %s" 22 "POSIX laat geen vergelijking toe tussen operatoren buiten als verklaringen of lussen" 23 "POSIX vereist 0 of 1 vergelijkingsoperator per conditie" 24 "POSIX vereist dat alle 3 de delen van een lus niet leeg zijn" -25 "POSIX laat geen exponentiële notatie toe" -26 "POSIX staat geen arrayreferenties toe als functieparameters" -27 "POSIX vereist dat de linkse beugel op dezelfde regel staat als de functiehoofding" -28 "POSIX staat niet toe dat strings worden toegewezen aan variabelen of arrays" +25 "POSIX vereist een nieuwe regel tussen een puntkomma en een functiedefinitie" +26 "POSIX laat geen exponentiële notatie toe" +27 "POSIX staat geen arrayreferenties toe als functieparameters" +28 "POSIX staat geen lege functies toe" +29 "POSIX vereist dat de linkse beugel op dezelfde regel staat als de functiehoofding" +30 "POSIX staat niet toe dat strings worden toegewezen aan variabelen of arrays" $ Runtime fouten. $set 5 1 "ongeldige ibase: moet [%lu, %lu] zijn" 2 "ongeldige obase: moet [%lu, %lu] zijn" 3 "ongeldige schaal: moet [%lu, %lu] zijn" 4 "ongeldige read() expressie" 5 "recursieve read() call" 6 "Variabele of matrix-element is het verkeerde type" 7 "Stapel heeft te weinig elementen" 8 "Stapel voor register %s heeft te weinig elementen" 9 "Verkeerd aantal parameters; hebben %zu nodig, hebben %zu" 10 "ongedefinieerde functie: %s()" 11 "kan geen nietige waarde in een uitdrukking gebruiken" $ Fatale fouten. $set 6 1 "geheugentoewijzing mislukt" 2 "I/O-fout" 3 "kon geen file openen: %s" 4 "bestand is geen tekst: %s" 5 "pad is een directory: %s" 6 "ongeldige opdrachtregeloptie: %s" 7 "optie vereist een argument: '%c' (\"%s\")" 8 "optie neemt geen argumenten aan: '%c' (\"%s\")" 9 "ongeldige opdrachtregeloptie argument: %s" diff --git a/contrib/bc/locales/pl_PL.ISO8859-2.msg b/contrib/bc/locales/pl_PL.ISO8859-2.msg index d1d77d7e0b57..a36d5fe8beb5 100644 --- a/contrib/bc/locales/pl_PL.ISO8859-2.msg +++ b/contrib/bc/locales/pl_PL.ISO8859-2.msg @@ -1,111 +1,113 @@ $ $ $ SPDX-License-Identifier: BSD-2-Clause $ $ $ Copyright (c) 2018-2021 Gavin D. Howard and contributors. $ $ $ Redistribution and use in source and binary forms, with or without $ modification, are permitted provided that the following conditions are met: $ $ $ * Redistributions of source code must retain the above copyright notice, this $ list of conditions and the following disclaimer. $ $ $ * Redistributions in binary form must reproduce the above copyright notice, $ this list of conditions and the following disclaimer in the documentation $ and/or other materials provided with the distribution. $ $ $ THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" $ AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE $ IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE $ ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE $ LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR $ CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF $ SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS $ INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN $ CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) $ ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE $ POSSIBILITY OF SUCH DAMAGE. $ $ $quote " $ Rne wiadomoci. $set 1 1 "Funkcja:" $ Typy bdw. $set 2 1 "Bd matematyczny:" 2 "Bd parse'a:" 3 "Bd biegu:" 4 "Bd miertelny:" 5 "Ostrzeenie:" $ Bdy matematyczne. $set 3 1 "liczba ujemna" 2 "numer nieintegracyjny" 3 "przelewanie: liczba nie mieci si w numerze sprztowym" 4 "dzielenie przez 0" $ Bdy Parse'a. $set 4 1 "koniec akt" 2 "niewany znak '%c'" 3 "koniec sznurka nie mg by znaleziony" 4 "koniec komentarza nie mg by znaleziony" 5 "niewany token" 6 "niewane wyraenie" 7 "puste wyraenie" 8 "nieprawidowe polecenie drukowania lub przesyania strumienia" 9 "nieprawidowa definicja funkcji" 10 "nieprawidowe przyporzdkowanie: lewa strona musi by elementem scale, ibase, obase, last, var lub element array" 11 "nie znaleziono zmiennej automatycznej" 12 "parametr funkcji lub auto \"%s%s\" ju istnieje" 13 "koca bloku nie mona byo znale" 14 "nie moe zwrci wartoci z funkcji void: %s()" 15 "var nie moe by odniesieniem: %s" 16 "POSIX nie zezwala na nazwy dusze ni 1 znak: %s" 17 "POSIX nie pozwala na komentarze skryptu '#'" 18 "POSIX nie pozwala na uycie nastpujcego sowa kluczowego: %s" 19 "POSIX nie dopuszcza kropki ('.') jako skrtu do ostatniego wyniku" 20 "POSIX wymaga nawiasw wok wyrae zwrotnych" 21 "POSIX nie pozwala nastpujcemu operatorowi: %s" 22 "POSIX nie pozwala na porwnywanie operatorw na zewntrz, jeli deklaracje lub ptle" 23 "POSIX wymaga 0 lub 1 operatora porwnawczego na jeden warunek" 24 "POSIX wymaga, aby wszystkie 3 czci ptli nie byy puste" -25 "POSIX nie pozwala na notacj wykadnicz" -26 "POSIX nie zezwala na odniesienia do tablicy jako parametrw funkcji" -27 "POSIX wymaga, aby lewe usztywnienie znajdowao si na tej samej linii co nagwek funkcji" -28 "POSIX nie pozwala na przypisywanie cigw znakw do zmiennych lub tablic" +25 "POSIX wymaga nowej linii pomidzy rednikiem a definicj funkcji" +26 "POSIX nie pozwala na notacj wykadnicz" +27 "POSIX nie zezwala na odniesienia do tablicy jako parametrw funkcji" +28 "POSIX nie dopuszcza funkcji void" +29 "POSIX wymaga, aby lewe usztywnienie znajdowao si na tej samej linii co nagwek funkcji" +30 "POSIX nie pozwala na przypisywanie cigw znakw do zmiennych lub tablic" $ Bdy Runtime'u. $set 5 1 "nieprawidowa ibase: musi by [%lu, %lu]" 2 "nieprawidowa obase: musi by [%lu, %lu]" 3 "nieprawidowa scale: musi by [%lu, %lu]" 4 "nieprawidowe wyraenie read()" 5 "powtarzalne wywoanie read()" 6 "element zmienny lub tablicowy jest niewaciwym typem" 7 "stos ma zbyt mao elementw" 8 "stos dla rejestru \"%s\" ma zbyt mao elementw" 9 "niewaciwa liczba parametrw; potrzeba %zu, maj %zu" 10 "niezdefiniowana funkcja: %s()" 11 "nie moe uy wartoci pustej w wyraeniu" $ Fatalne bdy. $set 6 1 "Alokacja pamici nie powioda si" 2 "Bd we/wy" 3 "nie mg otworzy pliku: %s" 4 "plik nie jest tekstem: %s" 5 "cieka to katalog: %s" 6 "nieprawidowa opcja wiersza polece: \"%s\"" 7 "opcja wymaga argumentu: '%c' (\"%s\")" 8 "opcja nie wymaga adnych argumentw: '%c' (\"%s\")" 9 "nieprawidowa argument opcja wiersza polece: \"%s\"" diff --git a/contrib/bc/locales/pl_PL.UTF-8.msg b/contrib/bc/locales/pl_PL.UTF-8.msg index a23a98edd1d2..ee297161a895 100644 --- a/contrib/bc/locales/pl_PL.UTF-8.msg +++ b/contrib/bc/locales/pl_PL.UTF-8.msg @@ -1,111 +1,113 @@ $ $ $ SPDX-License-Identifier: BSD-2-Clause $ $ $ Copyright (c) 2018-2021 Gavin D. Howard and contributors. $ $ $ Redistribution and use in source and binary forms, with or without $ modification, are permitted provided that the following conditions are met: $ $ $ * Redistributions of source code must retain the above copyright notice, this $ list of conditions and the following disclaimer. $ $ $ * Redistributions in binary form must reproduce the above copyright notice, $ this list of conditions and the following disclaimer in the documentation $ and/or other materials provided with the distribution. $ $ $ THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" $ AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE $ IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE $ ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE $ LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR $ CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF $ SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS $ INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN $ CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) $ ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE $ POSSIBILITY OF SUCH DAMAGE. $ $ $quote " $ Różne wiadomości. $set 1 1 "Funkcja:" $ Typy błędów. $set 2 1 "Błąd matematyczny:" 2 "Błąd parse'a:" 3 "Błąd biegu:" 4 "Błąd śmiertelny:" 5 "Ostrzeżenie:" $ Błędy matematyczne. $set 3 1 "liczba ujemna" 2 "numer nieintegracyjny" 3 "przelewanie: liczba nie mieści się w numerze sprzętowym" 4 "dzielenie przez 0" $ Błędy Parse'a. $set 4 1 "koniec akt" 2 "nieważny znak '%c'" 3 "koniec sznurka nie mógł być znaleziony" 4 "koniec komentarza nie mógł być znaleziony" 5 "nieważny token" 6 "nieważne wyrażenie" 7 "puste wyrażenie" 8 "nieprawidłowe polecenie drukowania lub przesyłania strumienia" 9 "nieprawidłowa definicja funkcji" 10 "nieprawidłowe przyporządkowanie: lewa strona musi być elementem scale, ibase, obase, last, var lub element array" 11 "nie znaleziono zmiennej automatycznej" 12 "parametr funkcji lub auto \"%s%s\" już istnieje" 13 "końca bloku nie można było znaleźć" 14 "nie może zwrócić wartości z funkcji void: %s()" 15 "var nie może być odniesieniem: %s" 16 "POSIX nie zezwala na nazwy dłuższe niż 1 znak: %s" 17 "POSIX nie pozwala na komentarze skryptu '#'" 18 "POSIX nie pozwala na użycie następującego słowa kluczowego: %s" 19 "POSIX nie dopuszcza kropki ('.') jako skrótu do ostatniego wyniku" 20 "POSIX wymaga nawiasów wokół wyrażeń zwrotnych" 21 "POSIX nie pozwala następującemu operatorowi: %s" 22 "POSIX nie pozwala na porównywanie operatorów na zewnątrz, jeśli deklaracje lub pętle" 23 "POSIX wymaga 0 lub 1 operatora porównawczego na jeden warunek" 24 "POSIX wymaga, aby wszystkie 3 części pętli nie były puste" -25 "POSIX nie pozwala na notację wykładniczą" -26 "POSIX nie zezwala na odniesienia do tablicy jako parametrów funkcji" -27 "POSIX wymaga, aby lewe usztywnienie znajdowało się na tej samej linii co nagłówek funkcji" -28 "POSIX nie pozwala na przypisywanie ciągów znaków do zmiennych lub tablic" +25 "POSIX wymaga nowej linii pomiędzy średnikiem a definicją funkcji" +26 "POSIX nie pozwala na notację wykładniczą" +27 "POSIX nie zezwala na odniesienia do tablicy jako parametrów funkcji" +28 "POSIX nie dopuszcza funkcji void" +29 "POSIX wymaga, aby lewe usztywnienie znajdowało się na tej samej linii co nagłówek funkcji" +30 "POSIX nie pozwala na przypisywanie ciągów znaków do zmiennych lub tablic" $ Błędy Runtime'u. $set 5 1 "nieprawidłowa ibase: musi być [%lu, %lu]" 2 "nieprawidłowa obase: musi być [%lu, %lu]" 3 "nieprawidłowa scale: musi być [%lu, %lu]" 4 "nieprawidłowe wyrażenie read()" 5 "powtarzalne wywołanie read()" 6 "element zmienny lub tablicowy jest niewłaściwym typem" 7 "stos ma zbyt mało elementów" 8 "stos dla rejestru \"%s\" ma zbyt mało elementów" 9 "niewłaściwa liczba parametrów; potrzeba %zu, mają %zu" 10 "niezdefiniowana funkcja: %s()" 11 "nie może użyć wartości pustej w wyrażeniu" $ Fatalne błędy. $set 6 1 "Alokacja pamięci nie powiodła się" 2 "Błąd we/wy" 3 "nie mógł otworzyć pliku: %s" 4 "plik nie jest tekstem: %s" 5 "ścieżka to katalog: %s" 6 "nieprawidłowa opcja wiersza poleceń: \"%s\"" 7 "opcja wymaga argumentu: '%c' (\"%s\")" 8 "opcja nie wymaga żadnych argumentów: '%c' (\"%s\")" 9 "nieprawidłowa argument opcja wiersza poleceń: \"%s\"" diff --git a/contrib/bc/locales/pt_PT.ISO8859-1.msg b/contrib/bc/locales/pt_PT.ISO8859-1.msg index 7a17f0642cc9..6197a73d0fe2 100644 --- a/contrib/bc/locales/pt_PT.ISO8859-1.msg +++ b/contrib/bc/locales/pt_PT.ISO8859-1.msg @@ -1,111 +1,113 @@ $ $ $ SPDX-License-Identifier: BSD-2-Clause $ $ $ Copyright (c) 2018-2021 Gavin D. Howard and contributors. $ $ $ Redistribution and use in source and binary forms, with or without $ modification, are permitted provided that the following conditions are met: $ $ $ * Redistributions of source code must retain the above copyright notice, this $ list of conditions and the following disclaimer. $ $ $ * Redistributions in binary form must reproduce the above copyright notice, $ this list of conditions and the following disclaimer in the documentation $ and/or other materials provided with the distribution. $ $ $ THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" $ AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE $ IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE $ ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE $ LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR $ CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF $ SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS $ INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN $ CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) $ ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE $ POSSIBILITY OF SUCH DAMAGE. $ $ $quote " $ Miscellaneous messages. $set 1 1 "Funo:" $ Error types. $set 2 1 "Erro de clculo:" 2 "Erro de anlise de sintaxe:" 3 "Erro de execuo:" 4 "Erro fatal:" 5 "Aviso:" $ Math errors. $set 3 1 "nmero negativo" 2 "nmero no inteiro" 3 "Estouro: nmero no cabe no registro" 4 "dividir por 0" $ Parse errors. $set 4 1 "fim do arquivo" 2 "caractere invlido '%c'" 3 "No foi possvel encontrar o final da string" 4 "No foi possvel encontrar o final do comentrio" 5 "token invlido" 6 "expresso invlida" 7 "expresso vazia" 8 "instruo de gravao ou de fluxo invlida" 9 "definio de funo invlida" 10 "atribuio invlida: a parte esquerda deve ser 'scale', 'ibase', 'obase', 'last', uma varivel ou um elemento da matriz" 11 "nenhuma varivel automtica encontrada" 12 "parmetro de funo ou varivel automtica \"%s%s\" j existe" 13 "fim do bloco no encontrado" 14 "uma funo 'void' no pode retornar um valor: %s()" 15 "Uma varivel no pode ser uma referncia: %s" 16 "POSIX no permite nomes com mais de 1 caractere: %s" 17 "POSIX no permite comentrios de script '#'" 18 "POSIX no permite a seguinte palavra-chave: %s" 19 "POSIX no permite um ponto ('.') como um atalho para o ltimo resultado" 20 "POSIX requer parnteses em torno de expresses de retorno" 21 "POSIX no permite o seguinte operador: %s" 22 "POSIX no permite operadores de comparao fora das expresses 'if' ou loops" 23 "POSIX requer operadores 0 ou 1 de comparao por condio" 24 "POSIX no permite uma expresso vazia em um loop 'for'" -25 "POSIX no permite notao exponencial" -26 "POSIX no permite referncias de matriz como parmetros de funo" -27 "POSIX requer que o cabealho da funo '{' estejam na mesma linha" -28 "POSIX no permite a atribuio de cadeias de caracteres a variveis ou matrizes" +25 "POSIX requer uma nova linha entre um ponto-e-vrgula e uma definio de funo" +26 "POSIX no permite notao exponencial" +27 "POSIX no permite referncias de matriz como parmetros de funo" +28 "POSIX no permite funes nulas" +29 "POSIX requer que o cabealho da funo '{' estejam na mesma linha" +30 "POSIX no permite a atribuio de cadeias de caracteres a variveis ou matrizes" $ Runtime errors. $set 5 1 "ibase invlido: deve ser [%lu, %lu]" 2 "obase invlido: deve ser [%lu, %lu]" 3 "scale invlida: deve ser [%lu, %lu]" 4 "expresso read() invlida" 5 "chamada read() recursiva" 6 "tipo errado de varivel ou elemento de matriz" 7 "pilha tem poucos elementos" 8 "pilha para registo \"%s\" tem poucos elementos" 9 "nmero incorreto de parmetros - esperado: %zu, obtido: %zu" 10 "funo indefinida: %s()" 11 "um valor 'void' no pode ser usado em uma expresso" $ Fatal errors. $set 6 1 "falha na alocao de memria" 2 "erro de entrada-sada" 3 "impossvel abrir o arquivo: %s" 4 "arquivo no texto: %s" 5 "caminho um diretrio: %s" 6 "opo de linha de comando invlida: \"%s\"" 7 "opo requer um argumento: '%c' (\"%s\")" 8 "a opo no aceita argumentos: '%c' (\"%s\")" 9 "argumento de opo de linha de comando invlido: \"%s\"" diff --git a/contrib/bc/locales/pt_PT.UTF-8.msg b/contrib/bc/locales/pt_PT.UTF-8.msg index 2f6a4683a376..768f8807ebfc 100644 --- a/contrib/bc/locales/pt_PT.UTF-8.msg +++ b/contrib/bc/locales/pt_PT.UTF-8.msg @@ -1,111 +1,113 @@ $ $ $ SPDX-License-Identifier: BSD-2-Clause $ $ $ Copyright (c) 2018-2021 Gavin D. Howard and contributors. $ $ $ Redistribution and use in source and binary forms, with or without $ modification, are permitted provided that the following conditions are met: $ $ $ * Redistributions of source code must retain the above copyright notice, this $ list of conditions and the following disclaimer. $ $ $ * Redistributions in binary form must reproduce the above copyright notice, $ this list of conditions and the following disclaimer in the documentation $ and/or other materials provided with the distribution. $ $ $ THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" $ AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE $ IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE $ ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE $ LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR $ CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF $ SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS $ INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN $ CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) $ ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE $ POSSIBILITY OF SUCH DAMAGE. $ $ $quote " $ Miscellaneous messages. $set 1 1 "Função:" $ Error types. $set 2 1 "Erro de cálculo:" 2 "Erro de análise de sintaxe:" 3 "Erro de execução:" 4 "Erro fatal:" 5 "Aviso:" $ Math errors. $set 3 1 "número negativo" 2 "número não inteiro" 3 "Estouro: número não cabe no registro" 4 "dividir por 0" $ Parse errors. $set 4 1 "fim do arquivo" 2 "caractere inválido '%c'" 3 "Não foi possível encontrar o final da string" 4 "Não foi possível encontrar o final do comentário" 5 "token inválido" 6 "expressão inválida" 7 "expressão vazia" 8 "instrução de gravação ou de fluxo inválida" 9 "definição de função inválida" 10 "atribuição inválida: a parte esquerda deve ser 'scale', 'ibase', 'obase', 'last', uma variável ou um elemento da matriz" 11 "nenhuma variável automática encontrada" 12 "parâmetro de função ou variável automática \"%s%s\" já existe" 13 "fim do bloco não encontrado" 14 "uma função 'void' não pode retornar um valor: %s()" 15 "Uma variável não pode ser uma referência: %s" 16 "POSIX não permite nomes com mais de 1 caractere: %s" 17 "POSIX não permite comentários de script '#'" 18 "POSIX não permite a seguinte palavra-chave: %s" 19 "POSIX não permite um ponto ('.') como um atalho para o último resultado" 20 "POSIX requer parênteses em torno de expressões de retorno" 21 "POSIX não permite o seguinte operador: %s" 22 "POSIX não permite operadores de comparação fora das expressões 'if' ou loops" 23 "POSIX requer operadores 0 ou 1 de comparação por condição" 24 "POSIX não permite uma expressão vazia em um loop 'for'" -25 "POSIX não permite notação exponencial" -26 "POSIX não permite referências de matriz como parâmetros de função" -27 "POSIX requer que o cabeçalho da função '{' estejam na mesma linha" -28 "POSIX não permite a atribuição de cadeias de caracteres a variáveis ou matrizes" +25 "POSIX requer uma nova linha entre um ponto-e-vírgula e uma definição de função" +26 "POSIX não permite notação exponencial" +27 "POSIX não permite referências de matriz como parâmetros de função" +28 "POSIX não permite funções nulas" +29 "POSIX requer que o cabeçalho da função '{' estejam na mesma linha" +30 "POSIX não permite a atribuição de cadeias de caracteres a variáveis ou matrizes" $ Runtime errors. $set 5 1 "ibase inválido: deve ser [%lu, %lu]" 2 "obase inválido: deve ser [%lu, %lu]" 3 "scale inválida: deve ser [%lu, %lu]" 4 "expressão read() inválida" 5 "chamada read() recursiva" 6 "tipo errado de variável ou elemento de matriz" 7 "pilha tem poucos elementos" 8 "pilha para registo \"%s\" tem poucos elementos" 9 "número incorreto de parâmetros - esperado: %zu, obtido: %zu" 10 "função indefinida: %s()" 11 "um valor 'void' não pode ser usado em uma expressão" $ Fatal errors. $set 6 1 "falha na alocação de memória" 2 "erro de entrada-saída" 3 "impossível abrir o arquivo: %s" 4 "arquivo não é texto: %s" 5 "caminho é um diretório: %s" 6 "opção de linha de comando inválida: \"%s\"" 7 "opção requer um argumento: '%c' (\"%s\")" 8 "a opção não aceita argumentos: '%c' (\"%s\")" 9 "argumento de opção de linha de comando inválido: \"%s\"" diff --git a/contrib/bc/locales/ru_RU.CP1251.msg b/contrib/bc/locales/ru_RU.CP1251.msg index 6b1d93aa2110..a094e08e4afb 100644 --- a/contrib/bc/locales/ru_RU.CP1251.msg +++ b/contrib/bc/locales/ru_RU.CP1251.msg @@ -1,111 +1,113 @@ $ $ $ SPDX-License-Identifier: BSD-2-Clause $ $ $ Copyright (c) 2018-2021 Gavin D. Howard and contributors. $ $ $ Redistribution and use in source and binary forms, with or without $ modification, are permitted provided that the following conditions are met: $ $ $ * Redistributions of source code must retain the above copyright notice, this $ list of conditions and the following disclaimer. $ $ $ * Redistributions in binary form must reproduce the above copyright notice, $ this list of conditions and the following disclaimer in the documentation $ and/or other materials provided with the distribution. $ $ $ THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" $ AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE $ IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE $ ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE $ LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR $ CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF $ SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS $ INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN $ CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) $ ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE $ POSSIBILITY OF SUCH DAMAGE. $ $ $quote " $ . $set 1 1 ":" $ . $set 2 1 " :" 2 " :" 3 " :" 4 " :" 5 ":" $ . $set 3 1 " " 2 " " 3 ": " 4 " 0" $ . $set 4 1 " " 2 " '%c'" 3 " " 4 " " 5 " " 6 " " 7 " " 8 " " 9 " " 10 " : scale, ibase, obase, last, " 11 " " 12 " auto \"%s%s\" " 13 " " 14 " void: %s()" 15 "var : %s" 16 "POSIX 1 : %s" 17 "POSIX '#'" 18 "POSIX : %s" 19 "POSIX ('.') " 20 "POSIX " 21 "POSIX : %s" 22 "POSIX , " 23 "POSIX 0 1 " 24 "POSIX , 3 " -25 "POSIX " -26 "POSIX " -27 "POSIX , , " -28 "POSIX " +25 "POSIX " +26 "POSIX " +27 "POSIX " +28 "POSIX " +29 "POSIX , , " +30 "POSIX " $ . $set 5 1 " ibase: [%lu, %lu]" 2 " obase: [%lu, %lu]" 3 " scale: [%lu, %lu]" 4 " read()" 5 " read()" 6 " " 7 " " 8 " \"%s\" " 9 " ; %zu, %zu" 10 " : %s()" 11 " " $ . $set 6 1 " " 2 " /" 3 " : %s" 4 " : %s" 5 " - : %s" 6 " : \"%s\"" 7 " : '%c' (\"%s\")" 8 " : '%c' (\"%s\")" 9 " : \"%s\"" diff --git a/contrib/bc/locales/ru_RU.CP866.msg b/contrib/bc/locales/ru_RU.CP866.msg index b693428b9a3c..79070cda2e0c 100644 --- a/contrib/bc/locales/ru_RU.CP866.msg +++ b/contrib/bc/locales/ru_RU.CP866.msg @@ -1,111 +1,113 @@ $ $ $ SPDX-License-Identifier: BSD-2-Clause $ $ $ Copyright (c) 2018-2021 Gavin D. Howard and contributors. $ $ $ Redistribution and use in source and binary forms, with or without $ modification, are permitted provided that the following conditions are met: $ $ $ * Redistributions of source code must retain the above copyright notice, this $ list of conditions and the following disclaimer. $ $ $ * Redistributions in binary form must reproduce the above copyright notice, $ this list of conditions and the following disclaimer in the documentation $ and/or other materials provided with the distribution. $ $ $ THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" $ AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE $ IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE $ ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE $ LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR $ CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF $ SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS $ INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN $ CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) $ ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE $ POSSIBILITY OF SUCH DAMAGE. $ $ $quote " $ ᮮ饭. $set 1 1 "㭪:" $ 訡. $set 2 1 "⥬᪠ 訡:" 2 "訡 ࠧ:" 3 "訡 믮:" 4 "⠫쭠 訡:" 5 "।०:" $ ⥬᪨ 訡. $set 3 1 "⥫쭮 ᫮" 2 "⥣஢ ᫮" 3 "९: 頥 " 4 " 0" $ 訡 ࠧ. $set 4 1 " 䠩" 2 "⨬ ᨬ '%c'" 3 " ப " 4 " " 5 "⢨⥫ ⮭" 6 "ࠢ쭮 ࠦ" 7 "⮥ ࠦ" 8 " ⢨⥫쭮 ⮪" 9 "। ⢨⥫쭮 㭪樨" 10 "୮ ᢮: ஭ scale, ibase, obase, last, ஬ ⮬ ᨢ" 11 "⮬᪠ ६ " 12 "ࠬ 㭪樨 auto \"%s%s\" 㦥 " 13 " " 14 " 祭 㭪樨 void: %s()" 15 "var 뫪: %s" 16 "POSIX ᪠ 1 ᨬ: %s" 17 "POSIX ᪠ ਥ 業 '#'" 18 "POSIX ᪠ ᫥饥 祢 ᫮: %s" 19 "POSIX ᪠ ('.') ⢥ 몠 ᫥ १" 20 "POSIX ॡ ᪮ ࠦ " 21 "POSIX ࠧ蠥 ᯮ짮 ᫥騩 : %s" 22 "POSIX ࠧ蠥 ࠬ ࠢ 室 ।, ᫨ ⢥ত 横" 23 "POSIX ॡ 0 1 ࠢ ᫮" 24 "POSIX ॡ, ⮡ 3 ⫨ 뫨 묨" -25 "POSIX ᪠ ᯮ樠쭮 樨" -26 "POSIX ᪠ 뫪 ᨢ ⢥ ࠬ஢ 㭪樨" -27 "POSIX ॡ, ⮡ ᪮ 뫠 ⮩ , 㭪樨" -28 "POSIX ᢠ ப ६ ᨢ" +25 "POSIX ॡ ப 窮 ⮩ । 㭪樨" +26 "POSIX ᪠ ᯮ樠쭮 樨" +27 "POSIX ᪠ 뫪 ᨢ ⢥ ࠬ஢ 㭪樨" +28 "POSIX ࠧ蠥 㭪樨 " +29 "POSIX ॡ, ⮡ ᪮ 뫠 ⮩ , 㭪樨" +30 "POSIX ᢠ ப ६ ᨢ" $ 訡 믮. $set 5 1 "⢨⥫ ibase: [%lu, %lu]" 2 "⢨⥫ obase: [%lu, %lu]" 3 "⢨⥫쭠 scale: [%lu, %lu]" 4 "⢨⥫쭮 ࠦ read()" 5 "४ᨢ 맮 read()" 6 "६ ᨢ  ࠢ ⨯" 7 "⮯ ᫨誮 ⮢" 8 "⮯ ॣ \"%s\" ᫨誮 ⮢" 9 "ࠢ쭮 ⢮ ࠬ஢; 㦭 %zu, 㦭 %zu" 10 "। 㭪: %s()" 11 " ᯮ짮 ⮥ 祭 ࠦ" $ ⠫ 訡. $set 6 1 " 㤠 뤥 " 2 "訡 /뢮" 3 " ᬮ 䠩: %s" 4 "䠩  ⥪⮢: %s" 5 " - ⠫: %s" 6 "ୠ ப: \"%s\"" 7 " ॡ 㬥: '%c' (\"%s\")" 8 " ਭ 㬥⮢: '%c' (\"%s\")" 9 " 㬥 樨 ப: \"%s\"" diff --git a/contrib/bc/locales/ru_RU.ISO8859-5.msg b/contrib/bc/locales/ru_RU.ISO8859-5.msg index 35af400c5831..4c544e94f846 100644 --- a/contrib/bc/locales/ru_RU.ISO8859-5.msg +++ b/contrib/bc/locales/ru_RU.ISO8859-5.msg @@ -1,111 +1,113 @@ $ $ $ SPDX-License-Identifier: BSD-2-Clause $ $ $ Copyright (c) 2018-2021 Gavin D. Howard and contributors. $ $ $ Redistribution and use in source and binary forms, with or without $ modification, are permitted provided that the following conditions are met: $ $ $ * Redistributions of source code must retain the above copyright notice, this $ list of conditions and the following disclaimer. $ $ $ * Redistributions in binary form must reproduce the above copyright notice, $ this list of conditions and the following disclaimer in the documentation $ and/or other materials provided with the distribution. $ $ $ THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" $ AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE $ IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE $ ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE $ LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR $ CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF $ SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS $ INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN $ CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) $ ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE $ POSSIBILITY OF SUCH DAMAGE. $ $ $quote " $ . $set 1 1 ":" $ . $set 2 1 " :" 2 " :" 3 " :" 4 " :" 5 ":" $ . $set 3 1 " " 2 " " 3 ": " 4 " 0" $ . $set 4 1 " " 2 " '%c'" 3 " " 4 " " 5 " " 6 " " 7 " " 8 " " 9 " " 10 " : scale, ibase, obase, last, " 11 " " 12 " auto \"%s%s\" " 13 " " 14 " void: %s()" 15 "var : %s" 16 "POSIX 1 : %s" 17 "POSIX '#'" 18 "POSIX : %s" 19 "POSIX ('.') " 20 "POSIX " 21 "POSIX : %s" 22 "POSIX , " 23 "POSIX 0 1 " 24 "POSIX , 3 " -25 "POSIX " -26 "POSIX " -27 "POSIX , , " -28 "POSIX " +25 "POSIX " +26 "POSIX " +27 "POSIX " +28 "POSIX " +29 "POSIX , , " +30 "POSIX " $ . $set 5 1 " ibase: [%lu, %lu]" 2 " obase: [%lu, %lu]" 3 " scale: [%lu, %lu]" 4 " read()" 5 " read()" 6 " " 7 " " 8 " \"%s\" " 9 " ; %zu, %zu" 10 " : %s()" 11 " " $ . $set 6 1 " " 2 " /" 3 " : %s" 4 " : %s" 5 " - : %s" 6 " : \"%s\"" 7 " : '%c' (\"%s\")" 8 " : '%c' (\"%s\")" 9 " : \"%s\"" diff --git a/contrib/bc/locales/ru_RU.KOI8-R.msg b/contrib/bc/locales/ru_RU.KOI8-R.msg index 98c667095852..50c716b5ca2e 100644 --- a/contrib/bc/locales/ru_RU.KOI8-R.msg +++ b/contrib/bc/locales/ru_RU.KOI8-R.msg @@ -1,110 +1,112 @@ $ $ $ SPDX-License-Identifier: BSD-2-Clause $ $ $ Copyright (c) 2018-2021 Gavin D. Howard and contributors. $ $ $ Redistribution and use in source and binary forms, with or without $ modification, are permitted provided that the following conditions are met: $ $ $ * Redistributions of source code must retain the above copyright notice, this $ list of conditions and the following disclaimer. $ $ $ * Redistributions in binary form must reproduce the above copyright notice, $ this list of conditions and the following disclaimer in the documentation $ and/or other materials provided with the distribution. $ $ $ THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" $ AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE $ IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE $ ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE $ LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR $ CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF $ SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS $ INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN $ CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) $ ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE $ POSSIBILITY OF SUCH DAMAGE. $ $ $quote " $ . $set 1 1 ":" $ . $set 2 1 " :" 2 " :" 3 " :" 4 " :" 5 ":" $ . $set 3 1 " " 2 " " 3 ": " 4 " 0" $ . $set 4 1 " " 2 " '%c'" 3 " " 4 " " 5 " " 6 " " 7 " " 8 " " 9 " " 10 " : scale, ibase, obase, last, " 11 " " 12 " auto \"%s%s\" " 13 " " 14 " void: %s()" 15 "var : %s" 16 "POSIX 1 : %s" 17 "POSIX '#'" 18 "POSIX : %s" 19 "POSIX ('.') " 20 "POSIX " 21 "POSIX : %s" 22 "POSIX , " 23 "POSIX 0 1 " 24 "POSIX , 3 " -25 "POSIX " -26 "POSIX " -27 "POSIX , , " -28 "POSIX " +25 "POSIX " +26 "POSIX " +27 "POSIX " +28 "POSIX " +29 "POSIX , , " +30 "POSIX " $ . $set 5 1 " ibase: [%lu, %lu]" 2 " obase: [%lu, %lu]" 3 " scale: [%lu, %lu]" 4 " read()" 5 " read()" 6 " " 7 " " 8 " ; %zu, %zu" 9 " : %s()" 10 " " $ . $set 6 1 " " 2 " /" 3 " : %s" 4 " : %s" 5 " - : %s" 6 " : \"%s\"" 7 " : '%c' (\"%s\")" 8 " : '%c' (\"%s\")" 9 " : \"%s\"" diff --git a/contrib/bc/locales/ru_RU.UTF-8.msg b/contrib/bc/locales/ru_RU.UTF-8.msg index f7c1dc58c4db..e37bb2182caf 100644 --- a/contrib/bc/locales/ru_RU.UTF-8.msg +++ b/contrib/bc/locales/ru_RU.UTF-8.msg @@ -1,111 +1,113 @@ $ $ $ SPDX-License-Identifier: BSD-2-Clause $ $ $ Copyright (c) 2018-2021 Gavin D. Howard and contributors. $ $ $ Redistribution and use in source and binary forms, with or without $ modification, are permitted provided that the following conditions are met: $ $ $ * Redistributions of source code must retain the above copyright notice, this $ list of conditions and the following disclaimer. $ $ $ * Redistributions in binary form must reproduce the above copyright notice, $ this list of conditions and the following disclaimer in the documentation $ and/or other materials provided with the distribution. $ $ $ THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" $ AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE $ IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE $ ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE $ LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR $ CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF $ SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS $ INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN $ CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) $ ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE $ POSSIBILITY OF SUCH DAMAGE. $ $ $quote " $ Разные сообщения. $set 1 1 "Функция:" $ Типы ошибок. $set 2 1 "Математическая ошибка:" 2 "Ошибка при разборе:" 3 "Ошибка выполнения:" 4 "Фатальная ошибка:" 5 "Предупреждение:" $ Математические ошибки. $set 3 1 "отрицательное число" 2 "неинтегрированное число" 3 "переполнение: номер не помещается в аппаратный номер" 4 "делить на 0" $ Ошибки при разборе. $set 4 1 "конец файла" 2 "недопустимый символ '%c'" 3 "конец строки не найден" 4 "конец комментария не найден" 5 "недействительный жетон" 6 "неправильное выражение" 7 "пустое выражение" 8 "заявление о недействительности печати или потока" 9 "определение недействительной функции" 10 "неверное присвоение: левая сторона должна быть scale, ibase, obase, last, варом или элементом массива" 11 "автоматическая переменная не найдена" 12 "параметр функции или auto \"%s%s\" уже существует" 13 "конец блока не найден" 14 "не может вернуть значение из функции void: %s()" 15 "var не может быть ссылкой: %s" 16 "POSIX не допускает имен длиннее 1 символа: %s" 17 "POSIX не допускает комментариев к сценарию '#'" 18 "POSIX не допускает следующее ключевое слово: %s" 19 "POSIX не допускает точку ('.') в качестве ярлыка для последнего результата" 20 "POSIX требует скобок вокруг выражений возврата" 21 "POSIX не разрешает использовать следующий оператор: %s" 22 "POSIX не разрешает операторам сравнения выходить за пределы, если утверждения или циклы" 23 "POSIX требует 0 или 1 оператора сравнения на условие" 24 "POSIX требует, чтобы все 3 части петли были непустыми" -25 "POSIX не допускает экспоненциальной нотации" -26 "POSIX не допускает ссылки на массив в качестве параметров функции" -27 "POSIX требует, чтобы левая скобка была на той же линии, что и заголовок функции" -28 "POSIX не позволяет присваивать строки переменным или массивам" +25 "POSIX требует наличия новой строки между точкой с запятой и определением функции" +26 "POSIX не допускает экспоненциальной нотации" +27 "POSIX не допускает ссылки на массив в качестве параметров функции" +28 "POSIX не разрешает функции пустоты" +29 "POSIX требует, чтобы левая скобка была на той же линии, что и заголовок функции" +30 "POSIX не позволяет присваивать строки переменным или массивам" $ Ошибки выполнения. $set 5 1 "Недействительный ibase: должен быть [%lu, %lu]" 2 "Недействительный obase: должен быть [%lu, %lu]" 3 "недействительная scale: должна быть [%lu, %lu]" 4 "недействительное выражение read()" 5 "рекурсивный вызов read()" 6 "переменная или элемент массива является неправильным типом" 7 "стопка имеет слишком мало элементов" 8 "стопка имеет для регистра \"%s\" слишком мало элементов" 9 "неправильное количество параметров; нужно %zu, нужно %zu" 10 "неопределенная функция: %s()" 11 "не может использовать пустое значение в выражении" $ Фатальные ошибки. $set 6 1 "Не удалось выделить память" 2 "Ошибка ввода/вывода" 3 "не смог открыть файл: %s" 4 "файл не является текстовым: %s" 5 "путь - это каталог: %s" 6 "неверная опция командной строки: \"%s\"" 7 "опция требует аргумента: '%c' (\"%s\")" 8 "опция не принимает аргументов: '%c' (\"%s\")" 9 "неверный аргумент опции командной строки: \"%s\"" diff --git a/contrib/bc/locales/zh_CN.GB18030.msg b/contrib/bc/locales/zh_CN.GB18030.msg index fb80db7de55d..a2210b19ed29 100644 --- a/contrib/bc/locales/zh_CN.GB18030.msg +++ b/contrib/bc/locales/zh_CN.GB18030.msg @@ -1,111 +1,113 @@ $ $ $ SPDX-License-Identifier: BSD-2-Clause $ $ $ Copyright (c) 2018-2021 Gavin D. Howard and contributors. $ $ $ Redistribution and use in source and binary forms, with or without $ modification, are permitted provided that the following conditions are met: $ $ $ * Redistributions of source code must retain the above copyright notice, this $ list of conditions and the following disclaimer. $ $ $ * Redistributions in binary form must reproduce the above copyright notice, $ this list of conditions and the following disclaimer in the documentation $ and/or other materials provided with the distribution. $ $ $ THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" $ AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE $ IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE $ ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE $ LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR $ CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF $ SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS $ INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN $ CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) $ ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE $ POSSIBILITY OF SUCH DAMAGE. $ $ $quote " $ Ϣ $set 1 1 "" $ ͡ $set 2 1 "ѧ" 2 "" 3 "ʱ" 4 "" 5 "棺" $ ѧ $set 3 1 "" 2 "" 3 "ֲӲ" 4 "0" $ $set 4 1 "ļ" 2 "Чַ'%c'" 3 "Ҳַβ" 4 "޷ҵ۵Ľβ" 5 "Ч" 6 "Ч" 7 ձ 8 "ЧĴӡ" 9 "ЧĹܶ" 10 "Ч䣺scaleibaseobaselastvarԪ" 11 "ûҵԶ" 12 "Զ \"%s%s\" Ѿ" 13 "Ҳĩ" 14 "ܴvoidзһֵ%s()" 15 "varΪο%s" 16 "POSIXֳ1ַ%s" 17 "POSIX'#'űע" 18 "POSIXʹ¹ؼ֣%s" 19 "POSIXþ('.')ΪĿݷʽ" 20 "POSIXҪڷرʽΧ" 21 "POSIX²%s" 22 "POSIXifѭ֮ıȽ" 23 "POSIXҪÿıȽΪ01" 24 "POSIXҪforѭ3ֱǷǿյ" -25 "POSIXʹָ" -26 "POSIXΪ" -27 "POSIXҪߵźͺͷͬһ" -28 "POSIXַ" +25 "POSIXҪڷֺźͺ֮ʹûз" +26 "POSIXʹָ" +27 "POSIXΪ" +28 "POSIXЧ" +29 "POSIXҪߵźͺͷͬһ" +30 "POSIXַ" $ ʱ $set 5 1 "Чibase: [%lu, %lu]" 2 "Чobase[%lu%lu]" 3 "Чscale[%lu%lu]" 4 "Чread()ʽ" 5 "ݹȡ()" 6 "ԪǴ" 7 "ջԪ̫" 8 "Ĵ \"%s\" ĶջԪ̫" 9 "Ҫ%zu%zu" 10 "δĺ%s()" 11 ڱʽʹÿֵ $ $set 6 1 "ڴʧ" 2 "I/O" 3 "޷ļ%s" 4 "ļı%s" 5 "·һĿ¼%s" 6 "Чѡ\"%s\"" 7 "ѡҪһ'%c'(\"%s\")" 8 "ѡҪ'%c'(\"%s\")" 9 "Чѡ\"%s\"" diff --git a/contrib/bc/locales/zh_CN.GB2312.msg b/contrib/bc/locales/zh_CN.GB2312.msg index fb80db7de55d..a2210b19ed29 100644 --- a/contrib/bc/locales/zh_CN.GB2312.msg +++ b/contrib/bc/locales/zh_CN.GB2312.msg @@ -1,111 +1,113 @@ $ $ $ SPDX-License-Identifier: BSD-2-Clause $ $ $ Copyright (c) 2018-2021 Gavin D. Howard and contributors. $ $ $ Redistribution and use in source and binary forms, with or without $ modification, are permitted provided that the following conditions are met: $ $ $ * Redistributions of source code must retain the above copyright notice, this $ list of conditions and the following disclaimer. $ $ $ * Redistributions in binary form must reproduce the above copyright notice, $ this list of conditions and the following disclaimer in the documentation $ and/or other materials provided with the distribution. $ $ $ THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" $ AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE $ IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE $ ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE $ LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR $ CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF $ SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS $ INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN $ CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) $ ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE $ POSSIBILITY OF SUCH DAMAGE. $ $ $quote " $ Ϣ $set 1 1 "" $ ͡ $set 2 1 "ѧ" 2 "" 3 "ʱ" 4 "" 5 "棺" $ ѧ $set 3 1 "" 2 "" 3 "ֲӲ" 4 "0" $ $set 4 1 "ļ" 2 "Чַ'%c'" 3 "Ҳַβ" 4 "޷ҵ۵Ľβ" 5 "Ч" 6 "Ч" 7 ձ 8 "ЧĴӡ" 9 "ЧĹܶ" 10 "Ч䣺scaleibaseobaselastvarԪ" 11 "ûҵԶ" 12 "Զ \"%s%s\" Ѿ" 13 "Ҳĩ" 14 "ܴvoidзһֵ%s()" 15 "varΪο%s" 16 "POSIXֳ1ַ%s" 17 "POSIX'#'űע" 18 "POSIXʹ¹ؼ֣%s" 19 "POSIXþ('.')ΪĿݷʽ" 20 "POSIXҪڷرʽΧ" 21 "POSIX²%s" 22 "POSIXifѭ֮ıȽ" 23 "POSIXҪÿıȽΪ01" 24 "POSIXҪforѭ3ֱǷǿյ" -25 "POSIXʹָ" -26 "POSIXΪ" -27 "POSIXҪߵźͺͷͬһ" -28 "POSIXַ" +25 "POSIXҪڷֺźͺ֮ʹûз" +26 "POSIXʹָ" +27 "POSIXΪ" +28 "POSIXЧ" +29 "POSIXҪߵźͺͷͬһ" +30 "POSIXַ" $ ʱ $set 5 1 "Чibase: [%lu, %lu]" 2 "Чobase[%lu%lu]" 3 "Чscale[%lu%lu]" 4 "Чread()ʽ" 5 "ݹȡ()" 6 "ԪǴ" 7 "ջԪ̫" 8 "Ĵ \"%s\" ĶջԪ̫" 9 "Ҫ%zu%zu" 10 "δĺ%s()" 11 ڱʽʹÿֵ $ $set 6 1 "ڴʧ" 2 "I/O" 3 "޷ļ%s" 4 "ļı%s" 5 "·һĿ¼%s" 6 "Чѡ\"%s\"" 7 "ѡҪһ'%c'(\"%s\")" 8 "ѡҪ'%c'(\"%s\")" 9 "Чѡ\"%s\"" diff --git a/contrib/bc/locales/zh_CN.GBK.msg b/contrib/bc/locales/zh_CN.GBK.msg index fb80db7de55d..a2210b19ed29 100644 --- a/contrib/bc/locales/zh_CN.GBK.msg +++ b/contrib/bc/locales/zh_CN.GBK.msg @@ -1,111 +1,113 @@ $ $ $ SPDX-License-Identifier: BSD-2-Clause $ $ $ Copyright (c) 2018-2021 Gavin D. Howard and contributors. $ $ $ Redistribution and use in source and binary forms, with or without $ modification, are permitted provided that the following conditions are met: $ $ $ * Redistributions of source code must retain the above copyright notice, this $ list of conditions and the following disclaimer. $ $ $ * Redistributions in binary form must reproduce the above copyright notice, $ this list of conditions and the following disclaimer in the documentation $ and/or other materials provided with the distribution. $ $ $ THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" $ AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE $ IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE $ ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE $ LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR $ CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF $ SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS $ INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN $ CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) $ ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE $ POSSIBILITY OF SUCH DAMAGE. $ $ $quote " $ Ϣ $set 1 1 "" $ ͡ $set 2 1 "ѧ" 2 "" 3 "ʱ" 4 "" 5 "棺" $ ѧ $set 3 1 "" 2 "" 3 "ֲӲ" 4 "0" $ $set 4 1 "ļ" 2 "Чַ'%c'" 3 "Ҳַβ" 4 "޷ҵ۵Ľβ" 5 "Ч" 6 "Ч" 7 ձ 8 "ЧĴӡ" 9 "ЧĹܶ" 10 "Ч䣺scaleibaseobaselastvarԪ" 11 "ûҵԶ" 12 "Զ \"%s%s\" Ѿ" 13 "Ҳĩ" 14 "ܴvoidзһֵ%s()" 15 "varΪο%s" 16 "POSIXֳ1ַ%s" 17 "POSIX'#'űע" 18 "POSIXʹ¹ؼ֣%s" 19 "POSIXþ('.')ΪĿݷʽ" 20 "POSIXҪڷرʽΧ" 21 "POSIX²%s" 22 "POSIXifѭ֮ıȽ" 23 "POSIXҪÿıȽΪ01" 24 "POSIXҪforѭ3ֱǷǿյ" -25 "POSIXʹָ" -26 "POSIXΪ" -27 "POSIXҪߵźͺͷͬһ" -28 "POSIXַ" +25 "POSIXҪڷֺźͺ֮ʹûз" +26 "POSIXʹָ" +27 "POSIXΪ" +28 "POSIXЧ" +29 "POSIXҪߵźͺͷͬһ" +30 "POSIXַ" $ ʱ $set 5 1 "Чibase: [%lu, %lu]" 2 "Чobase[%lu%lu]" 3 "Чscale[%lu%lu]" 4 "Чread()ʽ" 5 "ݹȡ()" 6 "ԪǴ" 7 "ջԪ̫" 8 "Ĵ \"%s\" ĶջԪ̫" 9 "Ҫ%zu%zu" 10 "δĺ%s()" 11 ڱʽʹÿֵ $ $set 6 1 "ڴʧ" 2 "I/O" 3 "޷ļ%s" 4 "ļı%s" 5 "·һĿ¼%s" 6 "Чѡ\"%s\"" 7 "ѡҪһ'%c'(\"%s\")" 8 "ѡҪ'%c'(\"%s\")" 9 "Чѡ\"%s\"" diff --git a/contrib/bc/locales/zh_CN.UTF-8.msg b/contrib/bc/locales/zh_CN.UTF-8.msg index c327c0b1b98c..92d1bb767cb0 100644 --- a/contrib/bc/locales/zh_CN.UTF-8.msg +++ b/contrib/bc/locales/zh_CN.UTF-8.msg @@ -1,111 +1,113 @@ $ $ $ SPDX-License-Identifier: BSD-2-Clause $ $ $ Copyright (c) 2018-2021 Gavin D. Howard and contributors. $ $ $ Redistribution and use in source and binary forms, with or without $ modification, are permitted provided that the following conditions are met: $ $ $ * Redistributions of source code must retain the above copyright notice, this $ list of conditions and the following disclaimer. $ $ $ * Redistributions in binary form must reproduce the above copyright notice, $ this list of conditions and the following disclaimer in the documentation $ and/or other materials provided with the distribution. $ $ $ THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" $ AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE $ IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE $ ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE $ LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR $ CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF $ SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS $ INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN $ CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) $ ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE $ POSSIBILITY OF SUCH DAMAGE. $ $ $quote " $ 杂项信息。 $set 1 1 "函数：" $ 错误类型。 $set 2 1 "数学错误：" 2 "解析错误：" 3 "运行时错误：" 4 "致命错误：" 5 "警告：" $ 数学错误。 $set 3 1 "负数" 2 "非整数" 3 "溢出：数字不符合硬件号码" 4 "除以0" $ 解析错误。 $set 4 1 "文件结束" 2 "无效字符'%c'" 3 "找不到字符串尾部" 4 "无法找到评论的结尾" 5 "无效令牌" 6 "无效表达" 7 “空表达” 8 "无效的打印或流语句" 9 "无效的功能定义" 10 "无效分配：左侧必须是scale、ibase、obase、last、var或数组元素" 11 "没有找到自动变量" 12 "函数参数或自动参数 \"%s%s\" 已经存在" 13 "找不到区块末端" 14 "不能从void函数中返回一个值：%s()" 15 "var不能作为参考：%s" 16 "POSIX不允许名字超过1个字符：%s" 17 "POSIX不允许'#'脚本注释" 18 "POSIX不允许使用以下关键字：%s" 19 "POSIX不允许用句号('.')作为最后结果的快捷方式" 20 "POSIX要求在返回表达式周围加括号" 21 "POSIX不允许以下操作符：%s" 22 "POSIX不允许在if语句或循环之外的比较运算符" 23 "POSIX要求每个条件的比较运算符为0或1个" 24 "POSIX要求for循环的所有3个部分必须是非空的" -25 "POSIX不允许使用指数符号" -26 "POSIX不允许数组引用作为函数参数" -27 "POSIX要求左边的括号和函数头在同一行上" -28 "POSIX不允许将字符串分配给变量或数组" +25 "POSIX要求在分号和函数定义之间使用换行符" +26 "POSIX不允许使用指数符号" +27 "POSIX不允许数组引用作为函数参数" +28 "POSIX不允许无效函数" +29 "POSIX要求左边的括号和函数头在同一行上" +30 "POSIX不允许将字符串分配给变量或数组" $ 运行时错误。 $set 5 1 "无效的ibase: 必须是[%lu, %lu]" 2 "无效的obase：必须是[%lu，%lu]" 3 "无效的scale：必须是[%lu，%lu]" 4 "无效的read()表达式" 5 "递归读取()调用" 6 "变量或数组元素是错误的类型" 7 "堆栈的元素太少" 8 "寄存器 \"%s\" 的堆栈的元素太少" 9 "参数数量错误：需要%zu，有%zu" 10 "未定义的函数：%s()" 11 “不能在表达式中使用空值” $ 致命错误。 $set 6 1 "内存分配失败" 2 "I/O错误" 3 "无法打开文件：%s" 4 "文件不是文本：%s" 5 "路径是一个目录：%s" 6 "无效的命令行选项：\"%s\"" 7 "选项需要一个参数：'%c'(\"%s\")" 8 "选项不需要参数：'%c'(\"%s\")" 9 "无效的命令行选项参数：\"%s\"" diff --git a/contrib/bc/locales/zh_CN.eucCN.msg b/contrib/bc/locales/zh_CN.eucCN.msg index fb80db7de55d..a2210b19ed29 100644 --- a/contrib/bc/locales/zh_CN.eucCN.msg +++ b/contrib/bc/locales/zh_CN.eucCN.msg @@ -1,111 +1,113 @@ $ $ $ SPDX-License-Identifier: BSD-2-Clause $ $ $ Copyright (c) 2018-2021 Gavin D. Howard and contributors. $ $ $ Redistribution and use in source and binary forms, with or without $ modification, are permitted provided that the following conditions are met: $ $ $ * Redistributions of source code must retain the above copyright notice, this $ list of conditions and the following disclaimer. $ $ $ * Redistributions in binary form must reproduce the above copyright notice, $ this list of conditions and the following disclaimer in the documentation $ and/or other materials provided with the distribution. $ $ $ THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" $ AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE $ IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE $ ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE $ LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR $ CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF $ SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS $ INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN $ CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) $ ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE $ POSSIBILITY OF SUCH DAMAGE. $ $ $quote " $ Ϣ $set 1 1 "" $ ͡ $set 2 1 "ѧ" 2 "" 3 "ʱ" 4 "" 5 "棺" $ ѧ $set 3 1 "" 2 "" 3 "ֲӲ" 4 "0" $ $set 4 1 "ļ" 2 "Чַ'%c'" 3 "Ҳַβ" 4 "޷ҵ۵Ľβ" 5 "Ч" 6 "Ч" 7 ձ 8 "ЧĴӡ" 9 "ЧĹܶ" 10 "Ч䣺scaleibaseobaselastvarԪ" 11 "ûҵԶ" 12 "Զ \"%s%s\" Ѿ" 13 "Ҳĩ" 14 "ܴvoidзһֵ%s()" 15 "varΪο%s" 16 "POSIXֳ1ַ%s" 17 "POSIX'#'űע" 18 "POSIXʹ¹ؼ֣%s" 19 "POSIXþ('.')ΪĿݷʽ" 20 "POSIXҪڷرʽΧ" 21 "POSIX²%s" 22 "POSIXifѭ֮ıȽ" 23 "POSIXҪÿıȽΪ01" 24 "POSIXҪforѭ3ֱǷǿյ" -25 "POSIXʹָ" -26 "POSIXΪ" -27 "POSIXҪߵźͺͷͬһ" -28 "POSIXַ" +25 "POSIXҪڷֺźͺ֮ʹûз" +26 "POSIXʹָ" +27 "POSIXΪ" +28 "POSIXЧ" +29 "POSIXҪߵźͺͷͬһ" +30 "POSIXַ" $ ʱ $set 5 1 "Чibase: [%lu, %lu]" 2 "Чobase[%lu%lu]" 3 "Чscale[%lu%lu]" 4 "Чread()ʽ" 5 "ݹȡ()" 6 "ԪǴ" 7 "ջԪ̫" 8 "Ĵ \"%s\" ĶջԪ̫" 9 "Ҫ%zu%zu" 10 "δĺ%s()" 11 ڱʽʹÿֵ $ $set 6 1 "ڴʧ" 2 "I/O" 3 "޷ļ%s" 4 "ļı%s" 5 "·һĿ¼%s" 6 "Чѡ\"%s\"" 7 "ѡҪһ'%c'(\"%s\")" 8 "ѡҪ'%c'(\"%s\")" 9 "Чѡ\"%s\"" diff --git a/contrib/bc/manuals/bc/A.1 b/contrib/bc/manuals/bc/A.1 index bf6c9108456b..038932d52ada 100644 --- a/contrib/bc/manuals/bc/A.1 +++ b/contrib/bc/manuals/bc/A.1 @@ -1,2784 +1,2797 @@ .\" .\" SPDX-License-Identifier: BSD-2-Clause .\" .\" Copyright (c) 2018-2021 Gavin D. Howard and contributors. .\" .\" Redistribution and use in source and binary forms, with or without .\" modification, are permitted provided that the following conditions are met: .\" .\" * Redistributions of source code must retain the above copyright notice, .\" this list of conditions and the following disclaimer. .\" .\" * Redistributions in binary form must reproduce the above copyright notice, .\" this list of conditions and the following disclaimer in the documentation .\" and/or other materials provided with the distribution. .\" .\" THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" .\" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE .\" IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE .\" ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE .\" LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR .\" CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF .\" SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS .\" INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN .\" CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) .\" ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE .\" POSSIBILITY OF SUCH DAMAGE. .\" .TH "BC" "1" "June 2021" "Gavin D. Howard" "General Commands Manual" .SH NAME .PP bc - arbitrary-precision decimal arithmetic language and calculator .SH SYNOPSIS .PP \f[B]bc\f[R] [\f[B]-ghilPqRsvVw\f[R]] [\f[B]--global-stacks\f[R]] [\f[B]--help\f[R]] [\f[B]--interactive\f[R]] [\f[B]--mathlib\f[R]] [\f[B]--no-prompt\f[R]] [\f[B]--no-read-prompt\f[R]] [\f[B]--quiet\f[R]] [\f[B]--standard\f[R]] [\f[B]--warn\f[R]] [\f[B]--version\f[R]] [\f[B]-e\f[R] \f[I]expr\f[R]] [\f[B]--expression\f[R]=\f[I]expr\f[R]\&...] [\f[B]-f\f[R] \f[I]file\f[R]\&...] [\f[B]--file\f[R]=\f[I]file\f[R]\&...] [\f[I]file\f[R]\&...] .SH DESCRIPTION .PP bc(1) is an interactive processor for a language first standardized in 1991 by POSIX. (The current standard is here (https://pubs.opengroup.org/onlinepubs/9699919799/utilities/bc.html).) The language provides unlimited precision decimal arithmetic and is somewhat C-like, but there are differences. Such differences will be noted in this document. .PP After parsing and handling options, this bc(1) reads any files given on the command line and executes them before reading from \f[B]stdin\f[R]. .PP This bc(1) is a drop-in replacement for \f[I]any\f[R] bc(1), including (and especially) the GNU bc(1). It also has many extensions and extra features beyond other implementations. .PP \f[B]Note\f[R]: If running this bc(1) on \f[I]any\f[R] script meant for another bc(1) gives a parse error, it is probably because a word this bc(1) reserves as a keyword is used as the name of a function, variable, or array. To fix that, use the command-line option \f[B]-r\f[R] \f[I]keyword\f[R], where \f[I]keyword\f[R] is the keyword that is used as a name in the script. For more information, see the \f[B]OPTIONS\f[R] section. .PP If parsing scripts meant for other bc(1) implementations still does not work, that is a bug and should be reported. See the \f[B]BUGS\f[R] section. .SH OPTIONS .PP The following are the options that bc(1) accepts. .TP \f[B]-g\f[R], \f[B]--global-stacks\f[R] Turns the globals \f[B]ibase\f[R], \f[B]obase\f[R], \f[B]scale\f[R], and \f[B]seed\f[R] into stacks. .RS .PP This has the effect that a copy of the current value of all four are pushed onto a stack for every function call, as well as popped when every function returns. This means that functions can assign to any and all of those globals without worrying that the change will affect other functions. Thus, a hypothetical function named \f[B]output(x,b)\f[R] that simply printed \f[B]x\f[R] in base \f[B]b\f[R] could be written like this: .IP .nf \f[C] define void output(x, b) { obase=b x } \f[R] .fi .PP instead of like this: .IP .nf \f[C] define void output(x, b) { auto c c=obase obase=b x obase=c } \f[R] .fi .PP This makes writing functions much easier. .PP (\f[B]Note\f[R]: the function \f[B]output(x,b)\f[R] exists in the extended math library. See the \f[B]LIBRARY\f[R] section.) .PP However, since using this flag means that functions cannot set \f[B]ibase\f[R], \f[B]obase\f[R], \f[B]scale\f[R], or \f[B]seed\f[R] globally, functions that are made to do so cannot work anymore. There are two possible use cases for that, and each has a solution. .PP First, if a function is called on startup to turn bc(1) into a number converter, it is possible to replace that capability with various shell aliases. Examples: .IP .nf \f[C] alias d2o=\[dq]bc -e ibase=A -e obase=8\[dq] alias h2b=\[dq]bc -e ibase=G -e obase=2\[dq] \f[R] .fi .PP Second, if the purpose of a function is to set \f[B]ibase\f[R], \f[B]obase\f[R], \f[B]scale\f[R], or \f[B]seed\f[R] globally for any other purpose, it could be split into one to four functions (based on how many globals it sets) and each of those functions could return the desired value for a global. .PP For functions that set \f[B]seed\f[R], the value assigned to \f[B]seed\f[R] is not propagated to parent functions. This means that the sequence of pseudo-random numbers that they see will not be the same sequence of pseudo-random numbers that any parent sees. This is only the case once \f[B]seed\f[R] has been set. .PP If a function desires to not affect the sequence of pseudo-random numbers of its parents, but wants to use the same \f[B]seed\f[R], it can use the following line: .IP .nf \f[C] seed = seed \f[R] .fi .PP If the behavior of this option is desired for every run of bc(1), then users could make sure to define \f[B]BC_ENV_ARGS\f[R] and include this option (see the \f[B]ENVIRONMENT VARIABLES\f[R] section for more details). .PP If \f[B]-s\f[R], \f[B]-w\f[R], or any equivalents are used, this option is ignored. .PP This is a \f[B]non-portable extension\f[R]. .RE .TP \f[B]-h\f[R], \f[B]--help\f[R] Prints a usage message and quits. .TP \f[B]-i\f[R], \f[B]--interactive\f[R] Forces interactive mode. (See the \f[B]INTERACTIVE MODE\f[R] section.) .RS .PP This is a \f[B]non-portable extension\f[R]. .RE .TP \f[B]-L\f[R], \f[B]--no-line-length\f[R] Disables line length checking and prints numbers without backslashes and newlines. In other words, this option sets \f[B]BC_LINE_LENGTH\f[R] to \f[B]0\f[R] (see the \f[B]ENVIRONMENT VARIABLES\f[R] section). .RS .PP This is a \f[B]non-portable extension\f[R]. .RE .TP \f[B]-l\f[R], \f[B]--mathlib\f[R] Sets \f[B]scale\f[R] (see the \f[B]SYNTAX\f[R] section) to \f[B]20\f[R] and loads the included math library and the extended math library before running any code, including any expressions or files specified on the command line. .RS .PP To learn what is in the libraries, see the \f[B]LIBRARY\f[R] section. .RE .TP \f[B]-P\f[R], \f[B]--no-prompt\f[R] Disables the prompt in TTY mode. (The prompt is only enabled in TTY mode. See the \f[B]TTY MODE\f[R] section.) This is mostly for those users that do not want a prompt or are not used to having them in bc(1). Most of those users would want to put this option in \f[B]BC_ENV_ARGS\f[R] (see the \f[B]ENVIRONMENT VARIABLES\f[R] section). .RS .PP These options override the \f[B]BC_PROMPT\f[R] and \f[B]BC_TTY_MODE\f[R] environment variables (see the \f[B]ENVIRONMENT VARIABLES\f[R] section). .PP This is a \f[B]non-portable extension\f[R]. .RE .TP \f[B]-R\f[R], \f[B]--no-read-prompt\f[R] Disables the read prompt in TTY mode. (The read prompt is only enabled in TTY mode. See the \f[B]TTY MODE\f[R] section.) This is mostly for those users that do not want a read prompt or are not used to having them in bc(1). Most of those users would want to put this option in \f[B]BC_ENV_ARGS\f[R] (see the \f[B]ENVIRONMENT VARIABLES\f[R] section). This option is also useful in hash bang lines of bc(1) scripts that prompt for user input. .RS .PP This option does not disable the regular prompt because the read prompt is only used when the \f[B]read()\f[R] built-in function is called. .PP These options \f[I]do\f[R] override the \f[B]BC_PROMPT\f[R] and \f[B]BC_TTY_MODE\f[R] environment variables (see the \f[B]ENVIRONMENT VARIABLES\f[R] section), but only for the read prompt. .PP This is a \f[B]non-portable extension\f[R]. .RE .TP \f[B]-r\f[R] \f[I]keyword\f[R], \f[B]--redefine\f[R]=\f[I]keyword\f[R] Redefines \f[I]keyword\f[R] in order to allow it to be used as a function, variable, or array name. This is useful when this bc(1) gives parse errors when parsing scripts meant for other bc(1) implementations. .RS .PP The keywords this bc(1) allows to be redefined are: .IP \[bu] 2 \f[B]abs\f[R] .IP \[bu] 2 \f[B]asciify\f[R] .IP \[bu] 2 \f[B]continue\f[R] .IP \[bu] 2 \f[B]divmod\f[R] .IP \[bu] 2 \f[B]else\f[R] .IP \[bu] 2 \f[B]halt\f[R] .IP \[bu] 2 \f[B]irand\f[R] .IP \[bu] 2 \f[B]last\f[R] .IP \[bu] 2 \f[B]limits\f[R] .IP \[bu] 2 \f[B]maxibase\f[R] .IP \[bu] 2 \f[B]maxobase\f[R] .IP \[bu] 2 \f[B]maxrand\f[R] .IP \[bu] 2 \f[B]maxscale\f[R] .IP \[bu] 2 \f[B]modexp\f[R] .IP \[bu] 2 \f[B]print\f[R] .IP \[bu] 2 \f[B]rand\f[R] .IP \[bu] 2 \f[B]read\f[R] .IP \[bu] 2 \f[B]seed\f[R] .IP \[bu] 2 \f[B]stream\f[R] .PP If any of those keywords are used as a function, variable, or array name in a script, use this option with the keyword as the argument. If multiple are used, use this option for all of them; it can be used multiple times. .PP Keywords are \f[I]not\f[R] redefined when parsing the builtin math library (see the \f[B]LIBRARY\f[R] section). .PP It is a fatal error to redefine keywords mandated by the POSIX standard. It is a fatal error to attempt to redefine words that this bc(1) does not reserve as keywords. .RE .TP \f[B]-q\f[R], \f[B]--quiet\f[R] This option is for compatibility with the GNU bc(1) (https://www.gnu.org/software/bc/); it is a no-op. Without this option, GNU bc(1) prints a copyright header. This bc(1) only prints the copyright header if one or more of the \f[B]-v\f[R], \f[B]-V\f[R], or \f[B]--version\f[R] options are given. .RS .PP This is a \f[B]non-portable extension\f[R]. .RE .TP \f[B]-s\f[R], \f[B]--standard\f[R] Process exactly the language defined by the standard (https://pubs.opengroup.org/onlinepubs/9699919799/utilities/bc.html) and error if any extensions are used. .RS .PP This is a \f[B]non-portable extension\f[R]. .RE .TP \f[B]-v\f[R], \f[B]-V\f[R], \f[B]--version\f[R] Print the version information (copyright header) and exit. .RS .PP This is a \f[B]non-portable extension\f[R]. .RE .TP \f[B]-w\f[R], \f[B]--warn\f[R] Like \f[B]-s\f[R] and \f[B]--standard\f[R], except that warnings (and not errors) are printed for non-standard extensions and execution continues normally. .RS .PP This is a \f[B]non-portable extension\f[R]. .RE .TP \f[B]-z\f[R], \f[B]--leading-zeroes\f[R] Makes bc(1) print all numbers greater than \f[B]-1\f[R] and less than \f[B]1\f[R], and not equal to \f[B]0\f[R], with a leading zero. .RS .PP This can be set for individual numbers with the \f[B]plz(x)\f[R], plznl(x)**, \f[B]pnlz(x)\f[R], and \f[B]pnlznl(x)\f[R] functions in the extended math library (see the \f[B]LIBRARY\f[R] section). .PP This is a \f[B]non-portable extension\f[R]. .RE .TP \f[B]-e\f[R] \f[I]expr\f[R], \f[B]--expression\f[R]=\f[I]expr\f[R] Evaluates \f[I]expr\f[R]. If multiple expressions are given, they are evaluated in order. If files are given as well (see below), the expressions and files are evaluated in the order given. This means that if a file is given before an expression, the file is read in and evaluated first. .RS .PP If this option is given on the command-line (i.e., not in \f[B]BC_ENV_ARGS\f[R], see the \f[B]ENVIRONMENT VARIABLES\f[R] section), then after processing all expressions and files, bc(1) will exit, unless \f[B]-\f[R] (\f[B]stdin\f[R]) was given as an argument at least once to \f[B]-f\f[R] or \f[B]--file\f[R], whether on the command-line or in \f[B]BC_ENV_ARGS\f[R]. However, if any other \f[B]-e\f[R], \f[B]--expression\f[R], \f[B]-f\f[R], or \f[B]--file\f[R] arguments are given after \f[B]-f-\f[R] or equivalent is given, bc(1) will give a fatal error and exit. .PP This is a \f[B]non-portable extension\f[R]. .RE .TP \f[B]-f\f[R] \f[I]file\f[R], \f[B]--file\f[R]=\f[I]file\f[R] Reads in \f[I]file\f[R] and evaluates it, line by line, as though it were read through \f[B]stdin\f[R]. If expressions are also given (see above), the expressions are evaluated in the order given. .RS .PP If this option is given on the command-line (i.e., not in \f[B]BC_ENV_ARGS\f[R], see the \f[B]ENVIRONMENT VARIABLES\f[R] section), then after processing all expressions and files, bc(1) will exit, unless \f[B]-\f[R] (\f[B]stdin\f[R]) was given as an argument at least once to \f[B]-f\f[R] or \f[B]--file\f[R]. However, if any other \f[B]-e\f[R], \f[B]--expression\f[R], \f[B]-f\f[R], or \f[B]--file\f[R] arguments are given after \f[B]-f-\f[R] or equivalent is given, bc(1) will give a fatal error and exit. .PP This is a \f[B]non-portable extension\f[R]. .RE .PP All long options are \f[B]non-portable extensions\f[R]. .SH STDIN .PP If no files or expressions are given by the \f[B]-f\f[R], \f[B]--file\f[R], \f[B]-e\f[R], or \f[B]--expression\f[R] options, then bc(1) read from \f[B]stdin\f[R]. .PP However, there are a few caveats to this. .PP First, \f[B]stdin\f[R] is evaluated a line at a time. The only exception to this is if the parse cannot complete. That means that starting a string without ending it or starting a function, \f[B]if\f[R] statement, or loop without ending it will also cause bc(1) to not execute. .PP Second, after an \f[B]if\f[R] statement, bc(1) doesn\[cq]t know if an \f[B]else\f[R] statement will follow, so it will not execute until it knows there will not be an \f[B]else\f[R] statement. .SH STDOUT .PP Any non-error output is written to \f[B]stdout\f[R]. In addition, if history (see the \f[B]HISTORY\f[R] section) and the prompt (see the \f[B]TTY MODE\f[R] section) are enabled, both are output to \f[B]stdout\f[R]. .PP \f[B]Note\f[R]: Unlike other bc(1) implementations, this bc(1) will issue a fatal error (see the \f[B]EXIT STATUS\f[R] section) if it cannot write to \f[B]stdout\f[R], so if \f[B]stdout\f[R] is closed, as in \f[B]bc >&-\f[R], it will quit with an error. This is done so that bc(1) can report problems when \f[B]stdout\f[R] is redirected to a file. .PP If there are scripts that depend on the behavior of other bc(1) implementations, it is recommended that those scripts be changed to redirect \f[B]stdout\f[R] to \f[B]/dev/null\f[R]. .SH STDERR .PP Any error output is written to \f[B]stderr\f[R]. .PP \f[B]Note\f[R]: Unlike other bc(1) implementations, this bc(1) will issue a fatal error (see the \f[B]EXIT STATUS\f[R] section) if it cannot write to \f[B]stderr\f[R], so if \f[B]stderr\f[R] is closed, as in \f[B]bc 2>&-\f[R], it will quit with an error. This is done so that bc(1) can exit with an error code when \f[B]stderr\f[R] is redirected to a file. .PP If there are scripts that depend on the behavior of other bc(1) implementations, it is recommended that those scripts be changed to redirect \f[B]stderr\f[R] to \f[B]/dev/null\f[R]. .SH SYNTAX .PP The syntax for bc(1) programs is mostly C-like, with some differences. This bc(1) follows the POSIX standard (https://pubs.opengroup.org/onlinepubs/9699919799/utilities/bc.html), which is a much more thorough resource for the language this bc(1) accepts. This section is meant to be a summary and a listing of all the extensions to the standard. .PP In the sections below, \f[B]E\f[R] means expression, \f[B]S\f[R] means statement, and \f[B]I\f[R] means identifier. .PP Identifiers (\f[B]I\f[R]) start with a lowercase letter and can be followed by any number (up to \f[B]BC_NAME_MAX-1\f[R]) of lowercase letters (\f[B]a-z\f[R]), digits (\f[B]0-9\f[R]), and underscores (\f[B]_\f[R]). The regex is \f[B][a-z][a-z0-9_]*\f[R]. Identifiers with more than one character (letter) are a \f[B]non-portable extension\f[R]. .PP \f[B]ibase\f[R] is a global variable determining how to interpret constant numbers. It is the \[lq]input\[rq] base, or the number base used for interpreting input numbers. \f[B]ibase\f[R] is initially \f[B]10\f[R]. If the \f[B]-s\f[R] (\f[B]--standard\f[R]) and \f[B]-w\f[R] (\f[B]--warn\f[R]) flags were not given on the command line, the max allowable value for \f[B]ibase\f[R] is \f[B]36\f[R]. Otherwise, it is \f[B]16\f[R]. The min allowable value for \f[B]ibase\f[R] is \f[B]2\f[R]. The max allowable value for \f[B]ibase\f[R] can be queried in bc(1) programs with the \f[B]maxibase()\f[R] built-in function. .PP \f[B]obase\f[R] is a global variable determining how to output results. It is the \[lq]output\[rq] base, or the number base used for outputting numbers. \f[B]obase\f[R] is initially \f[B]10\f[R]. The max allowable value for \f[B]obase\f[R] is \f[B]BC_BASE_MAX\f[R] and can be queried in bc(1) programs with the \f[B]maxobase()\f[R] built-in function. The min allowable value for \f[B]obase\f[R] is \f[B]0\f[R]. If \f[B]obase\f[R] is \f[B]0\f[R], values are output in scientific notation, and if \f[B]obase\f[R] is \f[B]1\f[R], values are output in engineering notation. Otherwise, values are output in the specified base. .PP Outputting in scientific and engineering notations are \f[B]non-portable extensions\f[R]. .PP The \f[I]scale\f[R] of an expression is the number of digits in the result of the expression right of the decimal point, and \f[B]scale\f[R] is a global variable that sets the precision of any operations, with exceptions. \f[B]scale\f[R] is initially \f[B]0\f[R]. \f[B]scale\f[R] cannot be negative. The max allowable value for \f[B]scale\f[R] is \f[B]BC_SCALE_MAX\f[R] and can be queried in bc(1) programs with the \f[B]maxscale()\f[R] built-in function. .PP bc(1) has both \f[I]global\f[R] variables and \f[I]local\f[R] variables. All \f[I]local\f[R] variables are local to the function; they are parameters or are introduced in the \f[B]auto\f[R] list of a function (see the \f[B]FUNCTIONS\f[R] section). If a variable is accessed which is not a parameter or in the \f[B]auto\f[R] list, it is assumed to be \f[I]global\f[R]. If a parent function has a \f[I]local\f[R] variable version of a variable that a child function considers \f[I]global\f[R], the value of that \f[I]global\f[R] variable in the child function is the value of the variable in the parent function, not the value of the actual \f[I]global\f[R] variable. .PP All of the above applies to arrays as well. .PP The value of a statement that is an expression (i.e., any of the named expressions or operands) is printed unless the lowest precedence operator is an assignment operator \f[I]and\f[R] the expression is notsurrounded by parentheses. .PP The value that is printed is also assigned to the special variable \f[B]last\f[R]. A single dot (\f[B].\f[R]) may also be used as a synonym for \f[B]last\f[R]. These are \f[B]non-portable extensions\f[R]. .PP Either semicolons or newlines may separate statements. .SS Comments .PP There are two kinds of comments: .IP "1." 3 Block comments are enclosed in \f[B]/*\f[R] and \f[B]*/\f[R]. .IP "2." 3 Line comments go from \f[B]#\f[R] until, and not including, the next newline. This is a \f[B]non-portable extension\f[R]. .SS Named Expressions .PP The following are named expressions in bc(1): .IP "1." 3 Variables: \f[B]I\f[R] .IP "2." 3 Array Elements: \f[B]I[E]\f[R] .IP "3." 3 \f[B]ibase\f[R] .IP "4." 3 \f[B]obase\f[R] .IP "5." 3 \f[B]scale\f[R] .IP "6." 3 \f[B]seed\f[R] .IP "7." 3 \f[B]last\f[R] or a single dot (\f[B].\f[R]) .PP Numbers 6 and 7 are \f[B]non-portable extensions\f[R]. .PP The meaning of \f[B]seed\f[R] is dependent on the current pseudo-random number generator but is guaranteed to not change except for new major versions. .PP The \f[I]scale\f[R] and sign of the value may be significant. .PP If a previously used \f[B]seed\f[R] value is assigned to \f[B]seed\f[R] and used again, the pseudo-random number generator is guaranteed to produce the same sequence of pseudo-random numbers as it did when the \f[B]seed\f[R] value was previously used. .PP The exact value assigned to \f[B]seed\f[R] is not guaranteed to be returned if \f[B]seed\f[R] is queried again immediately. However, if \f[B]seed\f[R] \f[I]does\f[R] return a different value, both values, when assigned to \f[B]seed\f[R], are guaranteed to produce the same sequence of pseudo-random numbers. This means that certain values assigned to \f[B]seed\f[R] will \f[I]not\f[R] produce unique sequences of pseudo-random numbers. The value of \f[B]seed\f[R] will change after any use of the \f[B]rand()\f[R] and \f[B]irand(E)\f[R] operands (see the \f[I]Operands\f[R] subsection below), except if the parameter passed to \f[B]irand(E)\f[R] is \f[B]0\f[R], \f[B]1\f[R], or negative. .PP There is no limit to the length (number of significant decimal digits) or \f[I]scale\f[R] of the value that can be assigned to \f[B]seed\f[R]. .PP Variables and arrays do not interfere; users can have arrays named the same as variables. This also applies to functions (see the \f[B]FUNCTIONS\f[R] section), so a user can have a variable, array, and function that all have the same name, and they will not shadow each other, whether inside of functions or not. .PP Named expressions are required as the operand of \f[B]increment\f[R]/\f[B]decrement\f[R] operators and as the left side of \f[B]assignment\f[R] operators (see the \f[I]Operators\f[R] subsection). .SS Operands .PP The following are valid operands in bc(1): .IP " 1." 4 Numbers (see the \f[I]Numbers\f[R] subsection below). .IP " 2." 4 Array indices (\f[B]I[E]\f[R]). .IP " 3." 4 \f[B](E)\f[R]: The value of \f[B]E\f[R] (used to change precedence). .IP " 4." 4 \f[B]sqrt(E)\f[R]: The square root of \f[B]E\f[R]. \f[B]E\f[R] must be non-negative. .IP " 5." 4 \f[B]length(E)\f[R]: The number of significant decimal digits in \f[B]E\f[R]. Returns \f[B]1\f[R] for \f[B]0\f[R] with no decimal places. If given a string, the length of the string is returned. Passing a string to \f[B]length(E)\f[R] is a \f[B]non-portable extension\f[R]. .IP " 6." 4 \f[B]length(I[])\f[R]: The number of elements in the array \f[B]I\f[R]. This is a \f[B]non-portable extension\f[R]. .IP " 7." 4 \f[B]scale(E)\f[R]: The \f[I]scale\f[R] of \f[B]E\f[R]. .IP " 8." 4 \f[B]abs(E)\f[R]: The absolute value of \f[B]E\f[R]. This is a \f[B]non-portable extension\f[R]. .IP " 9." 4 \f[B]modexp(E, E, E)\f[R]: Modular exponentiation, where the first expression is the base, the second is the exponent, and the third is the modulus. All three values must be integers. The second argument must be non-negative. The third argument must be non-zero. This is a \f[B]non-portable extension\f[R]. .IP "10." 4 \f[B]divmod(E, E, I[])\f[R]: Division and modulus in one operation. This is for optimization. The first expression is the dividend, and the second is the divisor, which must be non-zero. The return value is the quotient, and the modulus is stored in index \f[B]0\f[R] of the provided array (the last argument). This is a \f[B]non-portable extension\f[R]. .IP "11." 4 \f[B]asciify(E)\f[R]: If \f[B]E\f[R] is a string, returns a string that is the first letter of its argument. If it is a number, calculates the number mod \f[B]256\f[R] and returns that number as a one-character string. This is a \f[B]non-portable extension\f[R]. .IP "12." 4 \f[B]I()\f[R], \f[B]I(E)\f[R], \f[B]I(E, E)\f[R], and so on, where \f[B]I\f[R] is an identifier for a non-\f[B]void\f[R] function (see the \f[I]Void Functions\f[R] subsection of the \f[B]FUNCTIONS\f[R] section). The \f[B]E\f[R] argument(s) may also be arrays of the form \f[B]I[]\f[R], which will automatically be turned into array references (see the \f[I]Array References\f[R] subsection of the \f[B]FUNCTIONS\f[R] section) if the corresponding parameter in the function definition is an array reference. .IP "13." 4 \f[B]read()\f[R]: Reads a line from \f[B]stdin\f[R] and uses that as an expression. The result of that expression is the result of the \f[B]read()\f[R] operand. This is a \f[B]non-portable extension\f[R]. .IP "14." 4 \f[B]maxibase()\f[R]: The max allowable \f[B]ibase\f[R]. This is a \f[B]non-portable extension\f[R]. .IP "15." 4 \f[B]maxobase()\f[R]: The max allowable \f[B]obase\f[R]. This is a \f[B]non-portable extension\f[R]. .IP "16." 4 \f[B]maxscale()\f[R]: The max allowable \f[B]scale\f[R]. This is a \f[B]non-portable extension\f[R]. .IP "17." 4 \f[B]line_length()\f[R]: The line length set with \f[B]BC_LINE_LENGTH\f[R] (see the \f[B]ENVIRONMENT VARIABLES\f[R] section). This is a \f[B]non-portable extension\f[R]. .IP "18." 4 \f[B]global_stacks()\f[R]: \f[B]0\f[R] if global stacks are not enabled with the \f[B]-g\f[R] or \f[B]--global-stacks\f[R] options, non-zero otherwise. See the \f[B]OPTIONS\f[R] section. This is a \f[B]non-portable extension\f[R]. .IP "19." 4 \f[B]leading_zero()\f[R]: \f[B]0\f[R] if leading zeroes are not enabled with the \f[B]-z\f[R] or \f[B]\[en]leading-zeroes\f[R] options, non-zero otherwise. See the \f[B]OPTIONS\f[R] section. This is a \f[B]non-portable extension\f[R]. .IP "20." 4 \f[B]rand()\f[R]: A pseudo-random integer between \f[B]0\f[R] (inclusive) and \f[B]BC_RAND_MAX\f[R] (inclusive). Using this operand will change the value of \f[B]seed\f[R]. This is a \f[B]non-portable extension\f[R]. .IP "21." 4 \f[B]irand(E)\f[R]: A pseudo-random integer between \f[B]0\f[R] (inclusive) and the value of \f[B]E\f[R] (exclusive). If \f[B]E\f[R] is negative or is a non-integer (\f[B]E\f[R]\[cq]s \f[I]scale\f[R] is not \f[B]0\f[R]), an error is raised, and bc(1) resets (see the \f[B]RESET\f[R] section) while \f[B]seed\f[R] remains unchanged. If \f[B]E\f[R] is larger than \f[B]BC_RAND_MAX\f[R], the higher bound is honored by generating several pseudo-random integers, multiplying them by appropriate powers of \f[B]BC_RAND_MAX+1\f[R], and adding them together. Thus, the size of integer that can be generated with this operand is unbounded. Using this operand will change the value of \f[B]seed\f[R], unless the value of \f[B]E\f[R] is \f[B]0\f[R] or \f[B]1\f[R]. In that case, \f[B]0\f[R] is returned, and \f[B]seed\f[R] is \f[I]not\f[R] changed. This is a \f[B]non-portable extension\f[R]. .IP "22." 4 \f[B]maxrand()\f[R]: The max integer returned by \f[B]rand()\f[R]. This is a \f[B]non-portable extension\f[R]. .PP The integers generated by \f[B]rand()\f[R] and \f[B]irand(E)\f[R] are guaranteed to be as unbiased as possible, subject to the limitations of the pseudo-random number generator. .PP \f[B]Note\f[R]: The values returned by the pseudo-random number generator with \f[B]rand()\f[R] and \f[B]irand(E)\f[R] are guaranteed to \f[I]NOT\f[R] be cryptographically secure. This is a consequence of using a seeded pseudo-random number generator. However, they \f[I]are\f[R] guaranteed to be reproducible with identical \f[B]seed\f[R] values. This means that the pseudo-random values from bc(1) should only be used where a reproducible stream of pseudo-random numbers is \f[I]ESSENTIAL\f[R]. In any other case, use a non-seeded pseudo-random number generator. .SS Numbers .PP Numbers are strings made up of digits, uppercase letters, and at most \f[B]1\f[R] period for a radix. Numbers can have up to \f[B]BC_NUM_MAX\f[R] digits. Uppercase letters are equal to \f[B]9\f[R] + their position in the alphabet (i.e., \f[B]A\f[R] equals \f[B]10\f[R], or \f[B]9+1\f[R]). If a digit or letter makes no sense with the current value of \f[B]ibase\f[R], they are set to the value of the highest valid digit in \f[B]ibase\f[R]. .PP Single-character numbers (i.e., \f[B]A\f[R] alone) take the value that they would have if they were valid digits, regardless of the value of \f[B]ibase\f[R]. This means that \f[B]A\f[R] alone always equals decimal \f[B]10\f[R] and \f[B]Z\f[R] alone always equals decimal \f[B]35\f[R]. .PP In addition, bc(1) accepts numbers in scientific notation. These have the form \f[B]e\f[R]. The exponent (the portion after the \f[B]e\f[R]) must be an integer. An example is \f[B]1.89237e9\f[R], which is equal to \f[B]1892370000\f[R]. Negative exponents are also allowed, so \f[B]4.2890e-3\f[R] is equal to \f[B]0.0042890\f[R]. .PP Using scientific notation is an error or warning if the \f[B]-s\f[R] or \f[B]-w\f[R], respectively, command-line options (or equivalents) are given. .PP \f[B]WARNING\f[R]: Both the number and the exponent in scientific notation are interpreted according to the current \f[B]ibase\f[R], but the number is still multiplied by \f[B]10\[ha]exponent\f[R] regardless of the current \f[B]ibase\f[R]. For example, if \f[B]ibase\f[R] is \f[B]16\f[R] and bc(1) is given the number string \f[B]FFeA\f[R], the resulting decimal number will be \f[B]2550000000000\f[R], and if bc(1) is given the number string \f[B]10e-4\f[R], the resulting decimal number will be \f[B]0.0016\f[R]. .PP Accepting input as scientific notation is a \f[B]non-portable extension\f[R]. .SS Operators .PP The following arithmetic and logical operators can be used. They are listed in order of decreasing precedence. Operators in the same group have the same precedence. .TP \f[B]++\f[R] \f[B]--\f[R] Type: Prefix and Postfix .RS .PP Associativity: None .PP Description: \f[B]increment\f[R], \f[B]decrement\f[R] .RE .TP \f[B]-\f[R] \f[B]!\f[R] Type: Prefix .RS .PP Associativity: None .PP Description: \f[B]negation\f[R], \f[B]boolean not\f[R] .RE .TP \f[B]$\f[R] Type: Postfix .RS .PP Associativity: None .PP Description: \f[B]truncation\f[R] .RE .TP \f[B]\[at]\f[R] Type: Binary .RS .PP Associativity: Right .PP Description: \f[B]set precision\f[R] .RE .TP \f[B]\[ha]\f[R] Type: Binary .RS .PP Associativity: Right .PP Description: \f[B]power\f[R] .RE .TP \f[B]*\f[R] \f[B]/\f[R] \f[B]%\f[R] Type: Binary .RS .PP Associativity: Left .PP Description: \f[B]multiply\f[R], \f[B]divide\f[R], \f[B]modulus\f[R] .RE .TP \f[B]+\f[R] \f[B]-\f[R] Type: Binary .RS .PP Associativity: Left .PP Description: \f[B]add\f[R], \f[B]subtract\f[R] .RE .TP \f[B]<<\f[R] \f[B]>>\f[R] Type: Binary .RS .PP Associativity: Left .PP Description: \f[B]shift left\f[R], \f[B]shift right\f[R] .RE .TP \f[B]=\f[R] \f[B]<<=\f[R] \f[B]>>=\f[R] \f[B]+=\f[R] \f[B]-=\f[R] \f[B]*=\f[R] \f[B]/=\f[R] \f[B]%=\f[R] \f[B]\[ha]=\f[R] \f[B]\[at]=\f[R] Type: Binary .RS .PP Associativity: Right .PP Description: \f[B]assignment\f[R] .RE .TP \f[B]==\f[R] \f[B]<=\f[R] \f[B]>=\f[R] \f[B]!=\f[R] \f[B]<\f[R] \f[B]>\f[R] Type: Binary .RS .PP Associativity: Left .PP Description: \f[B]relational\f[R] .RE .TP \f[B]&&\f[R] Type: Binary .RS .PP Associativity: Left .PP Description: \f[B]boolean and\f[R] .RE .TP \f[B]||\f[R] Type: Binary .RS .PP Associativity: Left .PP Description: \f[B]boolean or\f[R] .RE .PP The operators will be described in more detail below. .TP \f[B]++\f[R] \f[B]--\f[R] The prefix and postfix \f[B]increment\f[R] and \f[B]decrement\f[R] operators behave exactly like they would in C. They require a named expression (see the \f[I]Named Expressions\f[R] subsection) as an operand. .RS .PP The prefix versions of these operators are more efficient; use them where possible. .RE .TP \f[B]-\f[R] The \f[B]negation\f[R] operator returns \f[B]0\f[R] if a user attempts to negate any expression with the value \f[B]0\f[R]. Otherwise, a copy of the expression with its sign flipped is returned. .TP \f[B]!\f[R] The \f[B]boolean not\f[R] operator returns \f[B]1\f[R] if the expression is \f[B]0\f[R], or \f[B]0\f[R] otherwise. .RS .PP This is a \f[B]non-portable extension\f[R]. .RE .TP \f[B]$\f[R] The \f[B]truncation\f[R] operator returns a copy of the given expression with all of its \f[I]scale\f[R] removed. .RS .PP This is a \f[B]non-portable extension\f[R]. .RE .TP \f[B]\[at]\f[R] The \f[B]set precision\f[R] operator takes two expressions and returns a copy of the first with its \f[I]scale\f[R] equal to the value of the second expression. That could either mean that the number is returned without change (if the \f[I]scale\f[R] of the first expression matches the value of the second expression), extended (if it is less), or truncated (if it is more). .RS .PP The second expression must be an integer (no \f[I]scale\f[R]) and non-negative. .PP This is a \f[B]non-portable extension\f[R]. .RE .TP \f[B]\[ha]\f[R] The \f[B]power\f[R] operator (not the \f[B]exclusive or\f[R] operator, as it would be in C) takes two expressions and raises the first to the power of the value of the second. The \f[I]scale\f[R] of the result is equal to \f[B]scale\f[R]. .RS .PP The second expression must be an integer (no \f[I]scale\f[R]), and if it is negative, the first value must be non-zero. .RE .TP \f[B]*\f[R] The \f[B]multiply\f[R] operator takes two expressions, multiplies them, and returns the product. If \f[B]a\f[R] is the \f[I]scale\f[R] of the first expression and \f[B]b\f[R] is the \f[I]scale\f[R] of the second expression, the \f[I]scale\f[R] of the result is equal to \f[B]min(a+b,max(scale,a,b))\f[R] where \f[B]min()\f[R] and \f[B]max()\f[R] return the obvious values. .TP \f[B]/\f[R] The \f[B]divide\f[R] operator takes two expressions, divides them, and returns the quotient. The \f[I]scale\f[R] of the result shall be the value of \f[B]scale\f[R]. .RS .PP The second expression must be non-zero. .RE .TP \f[B]%\f[R] The \f[B]modulus\f[R] operator takes two expressions, \f[B]a\f[R] and \f[B]b\f[R], and evaluates them by 1) Computing \f[B]a/b\f[R] to current \f[B]scale\f[R] and 2) Using the result of step 1 to calculate \f[B]a-(a/b)*b\f[R] to \f[I]scale\f[R] \f[B]max(scale+scale(b),scale(a))\f[R]. .RS .PP The second expression must be non-zero. .RE .TP \f[B]+\f[R] The \f[B]add\f[R] operator takes two expressions, \f[B]a\f[R] and \f[B]b\f[R], and returns the sum, with a \f[I]scale\f[R] equal to the max of the \f[I]scale\f[R]s of \f[B]a\f[R] and \f[B]b\f[R]. .TP \f[B]-\f[R] The \f[B]subtract\f[R] operator takes two expressions, \f[B]a\f[R] and \f[B]b\f[R], and returns the difference, with a \f[I]scale\f[R] equal to the max of the \f[I]scale\f[R]s of \f[B]a\f[R] and \f[B]b\f[R]. .TP \f[B]<<\f[R] The \f[B]left shift\f[R] operator takes two expressions, \f[B]a\f[R] and \f[B]b\f[R], and returns a copy of the value of \f[B]a\f[R] with its decimal point moved \f[B]b\f[R] places to the right. .RS .PP The second expression must be an integer (no \f[I]scale\f[R]) and non-negative. .PP This is a \f[B]non-portable extension\f[R]. .RE .TP \f[B]>>\f[R] The \f[B]right shift\f[R] operator takes two expressions, \f[B]a\f[R] and \f[B]b\f[R], and returns a copy of the value of \f[B]a\f[R] with its decimal point moved \f[B]b\f[R] places to the left. .RS .PP The second expression must be an integer (no \f[I]scale\f[R]) and non-negative. .PP This is a \f[B]non-portable extension\f[R]. .RE .TP \f[B]=\f[R] \f[B]<<=\f[R] \f[B]>>=\f[R] \f[B]+=\f[R] \f[B]-=\f[R] \f[B]*=\f[R] \f[B]/=\f[R] \f[B]%=\f[R] \f[B]\[ha]=\f[R] \f[B]\[at]=\f[R] The \f[B]assignment\f[R] operators take two expressions, \f[B]a\f[R] and \f[B]b\f[R] where \f[B]a\f[R] is a named expression (see the \f[I]Named Expressions\f[R] subsection). .RS .PP For \f[B]=\f[R], \f[B]b\f[R] is copied and the result is assigned to \f[B]a\f[R]. For all others, \f[B]a\f[R] and \f[B]b\f[R] are applied as operands to the corresponding arithmetic operator and the result is assigned to \f[B]a\f[R]. .PP The \f[B]assignment\f[R] operators that correspond to operators that are extensions are themselves \f[B]non-portable extensions\f[R]. .RE .TP \f[B]==\f[R] \f[B]<=\f[R] \f[B]>=\f[R] \f[B]!=\f[R] \f[B]<\f[R] \f[B]>\f[R] The \f[B]relational\f[R] operators compare two expressions, \f[B]a\f[R] and \f[B]b\f[R], and if the relation holds, according to C language semantics, the result is \f[B]1\f[R]. Otherwise, it is \f[B]0\f[R]. .RS .PP Note that unlike in C, these operators have a lower precedence than the \f[B]assignment\f[R] operators, which means that \f[B]a=b>c\f[R] is interpreted as \f[B](a=b)>c\f[R]. .PP Also, unlike the standard (https://pubs.opengroup.org/onlinepubs/9699919799/utilities/bc.html) requires, these operators can appear anywhere any other expressions can be used. This allowance is a \f[B]non-portable extension\f[R]. .RE .TP \f[B]&&\f[R] The \f[B]boolean and\f[R] operator takes two expressions and returns \f[B]1\f[R] if both expressions are non-zero, \f[B]0\f[R] otherwise. .RS .PP This is \f[I]not\f[R] a short-circuit operator. .PP This is a \f[B]non-portable extension\f[R]. .RE .TP \f[B]||\f[R] The \f[B]boolean or\f[R] operator takes two expressions and returns \f[B]1\f[R] if one of the expressions is non-zero, \f[B]0\f[R] otherwise. .RS .PP This is \f[I]not\f[R] a short-circuit operator. .PP This is a \f[B]non-portable extension\f[R]. .RE .SS Statements .PP The following items are statements: .IP " 1." 4 \f[B]E\f[R] .IP " 2." 4 \f[B]{\f[R] \f[B]S\f[R] \f[B];\f[R] \&... \f[B];\f[R] \f[B]S\f[R] \f[B]}\f[R] .IP " 3." 4 \f[B]if\f[R] \f[B](\f[R] \f[B]E\f[R] \f[B])\f[R] \f[B]S\f[R] .IP " 4." 4 \f[B]if\f[R] \f[B](\f[R] \f[B]E\f[R] \f[B])\f[R] \f[B]S\f[R] \f[B]else\f[R] \f[B]S\f[R] .IP " 5." 4 \f[B]while\f[R] \f[B](\f[R] \f[B]E\f[R] \f[B])\f[R] \f[B]S\f[R] .IP " 6." 4 \f[B]for\f[R] \f[B](\f[R] \f[B]E\f[R] \f[B];\f[R] \f[B]E\f[R] \f[B];\f[R] \f[B]E\f[R] \f[B])\f[R] \f[B]S\f[R] .IP " 7." 4 An empty statement .IP " 8." 4 \f[B]break\f[R] .IP " 9." 4 \f[B]continue\f[R] .IP "10." 4 \f[B]quit\f[R] .IP "11." 4 \f[B]halt\f[R] .IP "12." 4 \f[B]limits\f[R] .IP "13." 4 A string of characters, enclosed in double quotes .IP "14." 4 \f[B]print\f[R] \f[B]E\f[R] \f[B],\f[R] \&... \f[B],\f[R] \f[B]E\f[R] .IP "15." 4 \f[B]stream\f[R] \f[B]E\f[R] \f[B],\f[R] \&... \f[B],\f[R] \f[B]E\f[R] .IP "16." 4 \f[B]I()\f[R], \f[B]I(E)\f[R], \f[B]I(E, E)\f[R], and so on, where \f[B]I\f[R] is an identifier for a \f[B]void\f[R] function (see the \f[I]Void Functions\f[R] subsection of the \f[B]FUNCTIONS\f[R] section). The \f[B]E\f[R] argument(s) may also be arrays of the form \f[B]I[]\f[R], which will automatically be turned into array references (see the \f[I]Array References\f[R] subsection of the \f[B]FUNCTIONS\f[R] section) if the corresponding parameter in the function definition is an array reference. .PP Numbers 4, 9, 11, 12, 14, 15, and 16 are \f[B]non-portable extensions\f[R]. .PP Also, as a \f[B]non-portable extension\f[R], any or all of the expressions in the header of a for loop may be omitted. If the condition (second expression) is omitted, it is assumed to be a constant \f[B]1\f[R]. .PP The \f[B]break\f[R] statement causes a loop to stop iterating and resume execution immediately following a loop. This is only allowed in loops. .PP The \f[B]continue\f[R] statement causes a loop iteration to stop early and returns to the start of the loop, including testing the loop condition. This is only allowed in loops. .PP The \f[B]if\f[R] \f[B]else\f[R] statement does the same thing as in C. .PP The \f[B]quit\f[R] statement causes bc(1) to quit, even if it is on a branch that will not be executed (it is a compile-time command). .PP The \f[B]halt\f[R] statement causes bc(1) to quit, if it is executed. (Unlike \f[B]quit\f[R] if it is on a branch of an \f[B]if\f[R] statement that is not executed, bc(1) does not quit.) .PP The \f[B]limits\f[R] statement prints the limits that this bc(1) is subject to. This is like the \f[B]quit\f[R] statement in that it is a compile-time command. .PP An expression by itself is evaluated and printed, followed by a newline. .PP Both scientific notation and engineering notation are available for printing the results of expressions. Scientific notation is activated by assigning \f[B]0\f[R] to \f[B]obase\f[R], and engineering notation is activated by assigning \f[B]1\f[R] to \f[B]obase\f[R]. To deactivate them, just assign a different value to \f[B]obase\f[R]. .PP Scientific notation and engineering notation are disabled if bc(1) is run with either the \f[B]-s\f[R] or \f[B]-w\f[R] command-line options (or equivalents). .PP Printing numbers in scientific notation and/or engineering notation is a \f[B]non-portable extension\f[R]. .SS Strings .PP If strings appear as a statement by themselves, they are printed without a trailing newline. .PP In addition to appearing as a lone statement by themselves, strings can be assigned to variables and array elements. They can also be passed to functions in variable parameters. .PP If any statement that expects a string is given a variable that had a string assigned to it, the statement acts as though it had received a string. .PP If any math operation is attempted on a string or a variable or array element that has been assigned a string, an error is raised, and bc(1) resets (see the \f[B]RESET\f[R] section). .PP Assigning strings to variables and array elements and passing them to functions are \f[B]non-portable extensions\f[R]. .SS Print Statement .PP The \[lq]expressions\[rq] in a \f[B]print\f[R] statement may also be strings. If they are, there are backslash escape sequences that are interpreted specially. What those sequences are, and what they cause to be printed, are shown below: .PP \f[B]\[rs]a\f[R]: \f[B]\[rs]a\f[R] .PP \f[B]\[rs]b\f[R]: \f[B]\[rs]b\f[R] .PP \f[B]\[rs]\[rs]\f[R]: \f[B]\[rs]\f[R] .PP \f[B]\[rs]e\f[R]: \f[B]\[rs]\f[R] .PP \f[B]\[rs]f\f[R]: \f[B]\[rs]f\f[R] .PP \f[B]\[rs]n\f[R]: \f[B]\[rs]n\f[R] .PP \f[B]\[rs]q\f[R]: \f[B]\[lq]\f[R] .PP \f[B]\[rs]r\f[R]: \f[B]\[rs]r\f[R] .PP \f[B]\[rs]t\f[R]: \f[B]\[rs]t\f[R] .PP Any other character following a backslash causes the backslash and character to be printed as-is. .PP Any non-string expression in a print statement shall be assigned to \f[B]last\f[R], like any other expression that is printed. .SS Stream Statement .PP The \[lq]expressions in a \f[B]stream\f[R] statement may also be strings. .PP If a \f[B]stream\f[R] statement is given a string, it prints the string as though the string had appeared as its own statement. In other words, the \f[B]stream\f[R] statement prints strings normally, without a newline. .PP If a \f[B]stream\f[R] statement is given a number, a copy of it is truncated and its absolute value is calculated. The result is then printed as though \f[B]obase\f[R] is \f[B]256\f[R] and each digit is interpreted as an 8-bit ASCII character, making it a byte stream. .SS Order of Evaluation .PP All expressions in a statment are evaluated left to right, except as necessary to maintain order of operations. This means, for example, assuming that \f[B]i\f[R] is equal to \f[B]0\f[R], in the expression .IP .nf \f[C] a[i++] = i++ \f[R] .fi .PP the first (or 0th) element of \f[B]a\f[R] is set to \f[B]1\f[R], and \f[B]i\f[R] is equal to \f[B]2\f[R] at the end of the expression. .PP This includes function arguments. Thus, assuming \f[B]i\f[R] is equal to \f[B]0\f[R], this means that in the expression .IP .nf \f[C] x(i++, i++) \f[R] .fi .PP the first argument passed to \f[B]x()\f[R] is \f[B]0\f[R], and the second argument is \f[B]1\f[R], while \f[B]i\f[R] is equal to \f[B]2\f[R] before the function starts executing. .SH FUNCTIONS .PP Function definitions are as follows: .IP .nf \f[C] define I(I,...,I){ auto I,...,I S;...;S return(E) } \f[R] .fi .PP Any \f[B]I\f[R] in the parameter list or \f[B]auto\f[R] list may be replaced with \f[B]I[]\f[R] to make a parameter or \f[B]auto\f[R] var an array, and any \f[B]I\f[R] in the parameter list may be replaced with \f[B]*I[]\f[R] to make a parameter an array reference. Callers of functions that take array references should not put an asterisk in the call; they must be called with just \f[B]I[]\f[R] like normal array parameters and will be automatically converted into references. .PP As a \f[B]non-portable extension\f[R], the opening brace of a \f[B]define\f[R] statement may appear on the next line. .PP As a \f[B]non-portable extension\f[R], the return statement may also be in one of the following forms: .IP "1." 3 \f[B]return\f[R] .IP "2." 3 \f[B]return\f[R] \f[B](\f[R] \f[B])\f[R] .IP "3." 3 \f[B]return\f[R] \f[B]E\f[R] .PP The first two, or not specifying a \f[B]return\f[R] statement, is equivalent to \f[B]return (0)\f[R], unless the function is a \f[B]void\f[R] function (see the \f[I]Void Functions\f[R] subsection below). .SS Void Functions .PP Functions can also be \f[B]void\f[R] functions, defined as follows: .IP .nf \f[C] define void I(I,...,I){ auto I,...,I S;...;S return } \f[R] .fi .PP They can only be used as standalone expressions, where such an expression would be printed alone, except in a print statement. .PP Void functions can only use the first two \f[B]return\f[R] statements listed above. They can also omit the return statement entirely. .PP The word \[lq]void\[rq] is not treated as a keyword; it is still possible to have variables, arrays, and functions named \f[B]void\f[R]. The word \[lq]void\[rq] is only treated specially right after the \f[B]define\f[R] keyword. .PP This is a \f[B]non-portable extension\f[R]. .SS Array References .PP For any array in the parameter list, if the array is declared in the form .IP .nf \f[C] *I[] \f[R] .fi .PP it is a \f[B]reference\f[R]. Any changes to the array in the function are reflected, when the function returns, to the array that was passed in. .PP Other than this, all function arguments are passed by value. .PP This is a \f[B]non-portable extension\f[R]. .SH LIBRARY .PP All of the functions below, including the functions in the extended math library (see the \f[I]Extended Library\f[R] subsection below), are available when the \f[B]-l\f[R] or \f[B]--mathlib\f[R] command-line flags are given, except that the extended math library is not available when the \f[B]-s\f[R] option, the \f[B]-w\f[R] option, or equivalents are given. .SS Standard Library .PP The standard (https://pubs.opengroup.org/onlinepubs/9699919799/utilities/bc.html) defines the following functions for the math library: .TP \f[B]s(x)\f[R] Returns the sine of \f[B]x\f[R], which is assumed to be in radians. .RS .PP This is a transcendental function (see the \f[I]Transcendental Functions\f[R] subsection below). .RE .TP \f[B]c(x)\f[R] Returns the cosine of \f[B]x\f[R], which is assumed to be in radians. .RS .PP This is a transcendental function (see the \f[I]Transcendental Functions\f[R] subsection below). .RE .TP \f[B]a(x)\f[R] Returns the arctangent of \f[B]x\f[R], in radians. .RS .PP This is a transcendental function (see the \f[I]Transcendental Functions\f[R] subsection below). .RE .TP \f[B]l(x)\f[R] Returns the natural logarithm of \f[B]x\f[R]. .RS .PP This is a transcendental function (see the \f[I]Transcendental Functions\f[R] subsection below). .RE .TP \f[B]e(x)\f[R] Returns the mathematical constant \f[B]e\f[R] raised to the power of \f[B]x\f[R]. .RS .PP This is a transcendental function (see the \f[I]Transcendental Functions\f[R] subsection below). .RE .TP \f[B]j(x, n)\f[R] Returns the bessel integer order \f[B]n\f[R] (truncated) of \f[B]x\f[R]. .RS .PP This is a transcendental function (see the \f[I]Transcendental Functions\f[R] subsection below). .RE .SS Extended Library .PP The extended library is \f[I]not\f[R] loaded when the \f[B]-s\f[R]/\f[B]--standard\f[R] or \f[B]-w\f[R]/\f[B]--warn\f[R] options are given since they are not part of the library defined by the standard (https://pubs.opengroup.org/onlinepubs/9699919799/utilities/bc.html). .PP The extended library is a \f[B]non-portable extension\f[R]. .TP \f[B]p(x, y)\f[R] Calculates \f[B]x\f[R] to the power of \f[B]y\f[R], even if \f[B]y\f[R] is not an integer, and returns the result to the current \f[B]scale\f[R]. .RS .PP It is an error if \f[B]y\f[R] is negative and \f[B]x\f[R] is \f[B]0\f[R]. .PP This is a transcendental function (see the \f[I]Transcendental Functions\f[R] subsection below). .RE .TP \f[B]r(x, p)\f[R] Returns \f[B]x\f[R] rounded to \f[B]p\f[R] decimal places according to the rounding mode round half away from \f[B]0\f[R] (https://en.wikipedia.org/wiki/Rounding#Round_half_away_from_zero). .TP \f[B]ceil(x, p)\f[R] Returns \f[B]x\f[R] rounded to \f[B]p\f[R] decimal places according to the rounding mode round away from \f[B]0\f[R] (https://en.wikipedia.org/wiki/Rounding#Rounding_away_from_zero). .TP \f[B]f(x)\f[R] Returns the factorial of the truncated absolute value of \f[B]x\f[R]. .TP \f[B]perm(n, k)\f[R] Returns the permutation of the truncated absolute value of \f[B]n\f[R] of the truncated absolute value of \f[B]k\f[R], if \f[B]k <= n\f[R]. If not, it returns \f[B]0\f[R]. .TP \f[B]comb(n, k)\f[R] Returns the combination of the truncated absolute value of \f[B]n\f[R] of the truncated absolute value of \f[B]k\f[R], if \f[B]k <= n\f[R]. If not, it returns \f[B]0\f[R]. .TP \f[B]l2(x)\f[R] Returns the logarithm base \f[B]2\f[R] of \f[B]x\f[R]. .RS .PP This is a transcendental function (see the \f[I]Transcendental Functions\f[R] subsection below). .RE .TP \f[B]l10(x)\f[R] Returns the logarithm base \f[B]10\f[R] of \f[B]x\f[R]. .RS .PP This is a transcendental function (see the \f[I]Transcendental Functions\f[R] subsection below). .RE .TP \f[B]log(x, b)\f[R] Returns the logarithm base \f[B]b\f[R] of \f[B]x\f[R]. .RS .PP This is a transcendental function (see the \f[I]Transcendental Functions\f[R] subsection below). .RE .TP \f[B]cbrt(x)\f[R] Returns the cube root of \f[B]x\f[R]. .TP \f[B]root(x, n)\f[R] Calculates the truncated value of \f[B]n\f[R], \f[B]r\f[R], and returns the \f[B]r\f[R]th root of \f[B]x\f[R] to the current \f[B]scale\f[R]. .RS .PP If \f[B]r\f[R] is \f[B]0\f[R] or negative, this raises an error and causes bc(1) to reset (see the \f[B]RESET\f[R] section). It also raises an error and causes bc(1) to reset if \f[B]r\f[R] is even and \f[B]x\f[R] is negative. .RE .TP \f[B]gcd(a, b)\f[R] Returns the greatest common divisor (factor) of the truncated absolute value of \f[B]a\f[R] and the truncated absolute value of \f[B]b\f[R]. .TP \f[B]lcm(a, b)\f[R] Returns the least common multiple of the truncated absolute value of \f[B]a\f[R] and the truncated absolute value of \f[B]b\f[R]. .TP \f[B]pi(p)\f[R] Returns \f[B]pi\f[R] to \f[B]p\f[R] decimal places. .RS .PP This is a transcendental function (see the \f[I]Transcendental Functions\f[R] subsection below). .RE .TP \f[B]t(x)\f[R] Returns the tangent of \f[B]x\f[R], which is assumed to be in radians. .RS .PP This is a transcendental function (see the \f[I]Transcendental Functions\f[R] subsection below). .RE .TP \f[B]a2(y, x)\f[R] Returns the arctangent of \f[B]y/x\f[R], in radians. If both \f[B]y\f[R] and \f[B]x\f[R] are equal to \f[B]0\f[R], it raises an error and causes bc(1) to reset (see the \f[B]RESET\f[R] section). Otherwise, if \f[B]x\f[R] is greater than \f[B]0\f[R], it returns \f[B]a(y/x)\f[R]. If \f[B]x\f[R] is less than \f[B]0\f[R], and \f[B]y\f[R] is greater than or equal to \f[B]0\f[R], it returns \f[B]a(y/x)+pi\f[R]. If \f[B]x\f[R] is less than \f[B]0\f[R], and \f[B]y\f[R] is less than \f[B]0\f[R], it returns \f[B]a(y/x)-pi\f[R]. If \f[B]x\f[R] is equal to \f[B]0\f[R], and \f[B]y\f[R] is greater than \f[B]0\f[R], it returns \f[B]pi/2\f[R]. If \f[B]x\f[R] is equal to \f[B]0\f[R], and \f[B]y\f[R] is less than \f[B]0\f[R], it returns \f[B]-pi/2\f[R]. .RS .PP This function is the same as the \f[B]atan2()\f[R] function in many programming languages. .PP This is a transcendental function (see the \f[I]Transcendental Functions\f[R] subsection below). .RE .TP \f[B]sin(x)\f[R] Returns the sine of \f[B]x\f[R], which is assumed to be in radians. .RS .PP This is an alias of \f[B]s(x)\f[R]. .PP This is a transcendental function (see the \f[I]Transcendental Functions\f[R] subsection below). .RE .TP \f[B]cos(x)\f[R] Returns the cosine of \f[B]x\f[R], which is assumed to be in radians. .RS .PP This is an alias of \f[B]c(x)\f[R]. .PP This is a transcendental function (see the \f[I]Transcendental Functions\f[R] subsection below). .RE .TP \f[B]tan(x)\f[R] Returns the tangent of \f[B]x\f[R], which is assumed to be in radians. .RS .PP If \f[B]x\f[R] is equal to \f[B]1\f[R] or \f[B]-1\f[R], this raises an error and causes bc(1) to reset (see the \f[B]RESET\f[R] section). .PP This is an alias of \f[B]t(x)\f[R]. .PP This is a transcendental function (see the \f[I]Transcendental Functions\f[R] subsection below). .RE .TP \f[B]atan(x)\f[R] Returns the arctangent of \f[B]x\f[R], in radians. .RS .PP This is an alias of \f[B]a(x)\f[R]. .PP This is a transcendental function (see the \f[I]Transcendental Functions\f[R] subsection below). .RE .TP \f[B]atan2(y, x)\f[R] Returns the arctangent of \f[B]y/x\f[R], in radians. If both \f[B]y\f[R] and \f[B]x\f[R] are equal to \f[B]0\f[R], it raises an error and causes bc(1) to reset (see the \f[B]RESET\f[R] section). Otherwise, if \f[B]x\f[R] is greater than \f[B]0\f[R], it returns \f[B]a(y/x)\f[R]. If \f[B]x\f[R] is less than \f[B]0\f[R], and \f[B]y\f[R] is greater than or equal to \f[B]0\f[R], it returns \f[B]a(y/x)+pi\f[R]. If \f[B]x\f[R] is less than \f[B]0\f[R], and \f[B]y\f[R] is less than \f[B]0\f[R], it returns \f[B]a(y/x)-pi\f[R]. If \f[B]x\f[R] is equal to \f[B]0\f[R], and \f[B]y\f[R] is greater than \f[B]0\f[R], it returns \f[B]pi/2\f[R]. If \f[B]x\f[R] is equal to \f[B]0\f[R], and \f[B]y\f[R] is less than \f[B]0\f[R], it returns \f[B]-pi/2\f[R]. .RS .PP This function is the same as the \f[B]atan2()\f[R] function in many programming languages. .PP This is an alias of \f[B]a2(y, x)\f[R]. .PP This is a transcendental function (see the \f[I]Transcendental Functions\f[R] subsection below). .RE .TP \f[B]r2d(x)\f[R] Converts \f[B]x\f[R] from radians to degrees and returns the result. .RS .PP This is a transcendental function (see the \f[I]Transcendental Functions\f[R] subsection below). .RE .TP \f[B]d2r(x)\f[R] Converts \f[B]x\f[R] from degrees to radians and returns the result. .RS .PP This is a transcendental function (see the \f[I]Transcendental Functions\f[R] subsection below). .RE .TP \f[B]frand(p)\f[R] Generates a pseudo-random number between \f[B]0\f[R] (inclusive) and \f[B]1\f[R] (exclusive) with the number of decimal digits after the decimal point equal to the truncated absolute value of \f[B]p\f[R]. If \f[B]p\f[R] is not \f[B]0\f[R], then calling this function will change the value of \f[B]seed\f[R]. If \f[B]p\f[R] is \f[B]0\f[R], then \f[B]0\f[R] is returned, and \f[B]seed\f[R] is \f[I]not\f[R] changed. .TP \f[B]ifrand(i, p)\f[R] Generates a pseudo-random number that is between \f[B]0\f[R] (inclusive) and the truncated absolute value of \f[B]i\f[R] (exclusive) with the number of decimal digits after the decimal point equal to the truncated absolute value of \f[B]p\f[R]. If the absolute value of \f[B]i\f[R] is greater than or equal to \f[B]2\f[R], and \f[B]p\f[R] is not \f[B]0\f[R], then calling this function will change the value of \f[B]seed\f[R]; otherwise, \f[B]0\f[R] is returned and \f[B]seed\f[R] is not changed. .TP \f[B]srand(x)\f[R] Returns \f[B]x\f[R] with its sign flipped with probability \f[B]0.5\f[R]. In other words, it randomizes the sign of \f[B]x\f[R]. .TP \f[B]brand()\f[R] Returns a random boolean value (either \f[B]0\f[R] or \f[B]1\f[R]). .TP \f[B]band(a, b)\f[R] Takes the truncated absolute value of both \f[B]a\f[R] and \f[B]b\f[R] and calculates and returns the result of the bitwise \f[B]and\f[R] operation between them. .RS .PP If you want to use signed two\[cq]s complement arguments, use \f[B]s2u(x)\f[R] to convert. .RE .TP \f[B]bor(a, b)\f[R] Takes the truncated absolute value of both \f[B]a\f[R] and \f[B]b\f[R] and calculates and returns the result of the bitwise \f[B]or\f[R] operation between them. .RS .PP If you want to use signed two\[cq]s complement arguments, use \f[B]s2u(x)\f[R] to convert. .RE .TP \f[B]bxor(a, b)\f[R] Takes the truncated absolute value of both \f[B]a\f[R] and \f[B]b\f[R] and calculates and returns the result of the bitwise \f[B]xor\f[R] operation between them. .RS .PP If you want to use signed two\[cq]s complement arguments, use \f[B]s2u(x)\f[R] to convert. .RE .TP \f[B]bshl(a, b)\f[R] Takes the truncated absolute value of both \f[B]a\f[R] and \f[B]b\f[R] and calculates and returns the result of \f[B]a\f[R] bit-shifted left by \f[B]b\f[R] places. .RS .PP If you want to use signed two\[cq]s complement arguments, use \f[B]s2u(x)\f[R] to convert. .RE .TP \f[B]bshr(a, b)\f[R] Takes the truncated absolute value of both \f[B]a\f[R] and \f[B]b\f[R] and calculates and returns the truncated result of \f[B]a\f[R] bit-shifted right by \f[B]b\f[R] places. .RS .PP If you want to use signed two\[cq]s complement arguments, use \f[B]s2u(x)\f[R] to convert. .RE .TP \f[B]bnotn(x, n)\f[R] Takes the truncated absolute value of \f[B]x\f[R] and does a bitwise not as though it has the same number of bytes as the truncated absolute value of \f[B]n\f[R]. .RS .PP If you want to a use signed two\[cq]s complement argument, use \f[B]s2u(x)\f[R] to convert. .RE .TP \f[B]bnot8(x)\f[R] Does a bitwise not of the truncated absolute value of \f[B]x\f[R] as though it has \f[B]8\f[R] binary digits (1 unsigned byte). .RS .PP If you want to a use signed two\[cq]s complement argument, use \f[B]s2u(x)\f[R] to convert. .RE .TP \f[B]bnot16(x)\f[R] Does a bitwise not of the truncated absolute value of \f[B]x\f[R] as though it has \f[B]16\f[R] binary digits (2 unsigned bytes). .RS .PP If you want to a use signed two\[cq]s complement argument, use \f[B]s2u(x)\f[R] to convert. .RE .TP \f[B]bnot32(x)\f[R] Does a bitwise not of the truncated absolute value of \f[B]x\f[R] as though it has \f[B]32\f[R] binary digits (4 unsigned bytes). .RS .PP If you want to a use signed two\[cq]s complement argument, use \f[B]s2u(x)\f[R] to convert. .RE .TP \f[B]bnot64(x)\f[R] Does a bitwise not of the truncated absolute value of \f[B]x\f[R] as though it has \f[B]64\f[R] binary digits (8 unsigned bytes). .RS .PP If you want to a use signed two\[cq]s complement argument, use \f[B]s2u(x)\f[R] to convert. .RE .TP \f[B]bnot(x)\f[R] Does a bitwise not of the truncated absolute value of \f[B]x\f[R] as though it has the minimum number of power of two unsigned bytes. .RS .PP If you want to a use signed two\[cq]s complement argument, use \f[B]s2u(x)\f[R] to convert. .RE .TP \f[B]brevn(x, n)\f[R] Runs a bit reversal on the truncated absolute value of \f[B]x\f[R] as though it has the same number of 8-bit bytes as the truncated absolute value of \f[B]n\f[R]. .RS .PP If you want to a use signed two\[cq]s complement argument, use \f[B]s2u(x)\f[R] to convert. .RE .TP \f[B]brev8(x)\f[R] Runs a bit reversal on the truncated absolute value of \f[B]x\f[R] as though it has 8 binary digits (1 unsigned byte). .RS .PP If you want to a use signed two\[cq]s complement argument, use \f[B]s2u(x)\f[R] to convert. .RE .TP \f[B]brev16(x)\f[R] Runs a bit reversal on the truncated absolute value of \f[B]x\f[R] as though it has 16 binary digits (2 unsigned bytes). .RS .PP If you want to a use signed two\[cq]s complement argument, use \f[B]s2u(x)\f[R] to convert. .RE .TP \f[B]brev32(x)\f[R] Runs a bit reversal on the truncated absolute value of \f[B]x\f[R] as though it has 32 binary digits (4 unsigned bytes). .RS .PP If you want to a use signed two\[cq]s complement argument, use \f[B]s2u(x)\f[R] to convert. .RE .TP \f[B]brev64(x)\f[R] Runs a bit reversal on the truncated absolute value of \f[B]x\f[R] as though it has 64 binary digits (8 unsigned bytes). .RS .PP If you want to a use signed two\[cq]s complement argument, use \f[B]s2u(x)\f[R] to convert. .RE .TP \f[B]brev(x)\f[R] Runs a bit reversal on the truncated absolute value of \f[B]x\f[R] as though it has the minimum number of power of two unsigned bytes. .RS .PP If you want to a use signed two\[cq]s complement argument, use \f[B]s2u(x)\f[R] to convert. .RE .TP \f[B]broln(x, p, n)\f[R] Does a left bitwise rotatation of the truncated absolute value of \f[B]x\f[R], as though it has the same number of unsigned 8-bit bytes as the truncated absolute value of \f[B]n\f[R], by the number of places equal to the truncated absolute value of \f[B]p\f[R] modded by the \f[B]2\f[R] to the power of the number of binary digits in \f[B]n\f[R] 8-bit bytes. .RS .PP If you want to a use signed two\[cq]s complement argument, use \f[B]s2u(x)\f[R] to convert. .RE .TP \f[B]brol8(x, p)\f[R] Does a left bitwise rotatation of the truncated absolute value of \f[B]x\f[R], as though it has \f[B]8\f[R] binary digits (\f[B]1\f[R] unsigned byte), by the number of places equal to the truncated absolute value of \f[B]p\f[R] modded by \f[B]2\f[R] to the power of \f[B]8\f[R]. .RS .PP If you want to a use signed two\[cq]s complement argument, use \f[B]s2u(x)\f[R] to convert. .RE .TP \f[B]brol16(x, p)\f[R] Does a left bitwise rotatation of the truncated absolute value of \f[B]x\f[R], as though it has \f[B]16\f[R] binary digits (\f[B]2\f[R] unsigned bytes), by the number of places equal to the truncated absolute value of \f[B]p\f[R] modded by \f[B]2\f[R] to the power of \f[B]16\f[R]. .RS .PP If you want to a use signed two\[cq]s complement argument, use \f[B]s2u(x)\f[R] to convert. .RE .TP \f[B]brol32(x, p)\f[R] Does a left bitwise rotatation of the truncated absolute value of \f[B]x\f[R], as though it has \f[B]32\f[R] binary digits (\f[B]2\f[R] unsigned bytes), by the number of places equal to the truncated absolute value of \f[B]p\f[R] modded by \f[B]2\f[R] to the power of \f[B]32\f[R]. .RS .PP If you want to a use signed two\[cq]s complement argument, use \f[B]s2u(x)\f[R] to convert. .RE .TP \f[B]brol64(x, p)\f[R] Does a left bitwise rotatation of the truncated absolute value of \f[B]x\f[R], as though it has \f[B]64\f[R] binary digits (\f[B]2\f[R] unsigned bytes), by the number of places equal to the truncated absolute value of \f[B]p\f[R] modded by \f[B]2\f[R] to the power of \f[B]64\f[R]. .RS .PP If you want to a use signed two\[cq]s complement argument, use \f[B]s2u(x)\f[R] to convert. .RE .TP \f[B]brol(x, p)\f[R] Does a left bitwise rotatation of the truncated absolute value of \f[B]x\f[R], as though it has the minimum number of power of two unsigned 8-bit bytes, by the number of places equal to the truncated absolute value of \f[B]p\f[R] modded by 2 to the power of the number of binary digits in the minimum number of 8-bit bytes. .RS .PP If you want to a use signed two\[cq]s complement argument, use \f[B]s2u(x)\f[R] to convert. .RE .TP \f[B]brorn(x, p, n)\f[R] Does a right bitwise rotatation of the truncated absolute value of \f[B]x\f[R], as though it has the same number of unsigned 8-bit bytes as the truncated absolute value of \f[B]n\f[R], by the number of places equal to the truncated absolute value of \f[B]p\f[R] modded by the \f[B]2\f[R] to the power of the number of binary digits in \f[B]n\f[R] 8-bit bytes. .RS .PP If you want to a use signed two\[cq]s complement argument, use \f[B]s2u(x)\f[R] to convert. .RE .TP \f[B]bror8(x, p)\f[R] Does a right bitwise rotatation of the truncated absolute value of \f[B]x\f[R], as though it has \f[B]8\f[R] binary digits (\f[B]1\f[R] unsigned byte), by the number of places equal to the truncated absolute value of \f[B]p\f[R] modded by \f[B]2\f[R] to the power of \f[B]8\f[R]. .RS .PP If you want to a use signed two\[cq]s complement argument, use \f[B]s2u(x)\f[R] to convert. .RE .TP \f[B]bror16(x, p)\f[R] Does a right bitwise rotatation of the truncated absolute value of \f[B]x\f[R], as though it has \f[B]16\f[R] binary digits (\f[B]2\f[R] unsigned bytes), by the number of places equal to the truncated absolute value of \f[B]p\f[R] modded by \f[B]2\f[R] to the power of \f[B]16\f[R]. .RS .PP If you want to a use signed two\[cq]s complement argument, use \f[B]s2u(x)\f[R] to convert. .RE .TP \f[B]bror32(x, p)\f[R] Does a right bitwise rotatation of the truncated absolute value of \f[B]x\f[R], as though it has \f[B]32\f[R] binary digits (\f[B]2\f[R] unsigned bytes), by the number of places equal to the truncated absolute value of \f[B]p\f[R] modded by \f[B]2\f[R] to the power of \f[B]32\f[R]. .RS .PP If you want to a use signed two\[cq]s complement argument, use \f[B]s2u(x)\f[R] to convert. .RE .TP \f[B]bror64(x, p)\f[R] Does a right bitwise rotatation of the truncated absolute value of \f[B]x\f[R], as though it has \f[B]64\f[R] binary digits (\f[B]2\f[R] unsigned bytes), by the number of places equal to the truncated absolute value of \f[B]p\f[R] modded by \f[B]2\f[R] to the power of \f[B]64\f[R]. .RS .PP If you want to a use signed two\[cq]s complement argument, use \f[B]s2u(x)\f[R] to convert. .RE .TP \f[B]bror(x, p)\f[R] Does a right bitwise rotatation of the truncated absolute value of \f[B]x\f[R], as though it has the minimum number of power of two unsigned 8-bit bytes, by the number of places equal to the truncated absolute value of \f[B]p\f[R] modded by 2 to the power of the number of binary digits in the minimum number of 8-bit bytes. .RS .PP If you want to a use signed two\[cq]s complement argument, use \f[B]s2u(x)\f[R] to convert. .RE .TP \f[B]bmodn(x, n)\f[R] Returns the modulus of the truncated absolute value of \f[B]x\f[R] by \f[B]2\f[R] to the power of the multiplication of the truncated absolute value of \f[B]n\f[R] and \f[B]8\f[R]. .RS .PP If you want to a use signed two\[cq]s complement argument, use \f[B]s2u(x)\f[R] to convert. .RE .TP \f[B]bmod8(x, n)\f[R] Returns the modulus of the truncated absolute value of \f[B]x\f[R] by \f[B]2\f[R] to the power of \f[B]8\f[R]. .RS .PP If you want to a use signed two\[cq]s complement argument, use \f[B]s2u(x)\f[R] to convert. .RE .TP \f[B]bmod16(x, n)\f[R] Returns the modulus of the truncated absolute value of \f[B]x\f[R] by \f[B]2\f[R] to the power of \f[B]16\f[R]. .RS .PP If you want to a use signed two\[cq]s complement argument, use \f[B]s2u(x)\f[R] to convert. .RE .TP \f[B]bmod32(x, n)\f[R] Returns the modulus of the truncated absolute value of \f[B]x\f[R] by \f[B]2\f[R] to the power of \f[B]32\f[R]. .RS .PP If you want to a use signed two\[cq]s complement argument, use \f[B]s2u(x)\f[R] to convert. .RE .TP \f[B]bmod64(x, n)\f[R] Returns the modulus of the truncated absolute value of \f[B]x\f[R] by \f[B]2\f[R] to the power of \f[B]64\f[R]. .RS .PP If you want to a use signed two\[cq]s complement argument, use \f[B]s2u(x)\f[R] to convert. .RE .TP \f[B]bunrev(t)\f[R] Assumes \f[B]t\f[R] is a bitwise-reversed number with an extra set bit one place more significant than the real most significant bit (which was the least significant bit in the original number). This number is reversed and returned without the extra set bit. .RS .PP This function is used to implement other bitwise functions; it is not meant to be used by users, but it can be. .RE .TP \f[B]plz(x)\f[R] If \f[B]x\f[R] is not equal to \f[B]0\f[R] and greater that \f[B]-1\f[R] and less than \f[B]1\f[R], it is printed with a leading zero, regardless of the use of the \f[B]-z\f[R] option (see the \f[B]OPTIONS\f[R] section) and without a trailing newline. .RS .PP Otherwise, \f[B]x\f[R] is printed normally, without a trailing newline. .RE .TP \f[B]plznl(x)\f[R] If \f[B]x\f[R] is not equal to \f[B]0\f[R] and greater that \f[B]-1\f[R] and less than \f[B]1\f[R], it is printed with a leading zero, regardless of the use of the \f[B]-z\f[R] option (see the \f[B]OPTIONS\f[R] section) and with a trailing newline. .RS .PP Otherwise, \f[B]x\f[R] is printed normally, with a trailing newline. .RE .TP \f[B]pnlz(x)\f[R] If \f[B]x\f[R] is not equal to \f[B]0\f[R] and greater that \f[B]-1\f[R] and less than \f[B]1\f[R], it is printed without a leading zero, regardless of the use of the \f[B]-z\f[R] option (see the \f[B]OPTIONS\f[R] section) and without a trailing newline. .RS .PP Otherwise, \f[B]x\f[R] is printed normally, without a trailing newline. .RE .TP \f[B]pnlznl(x)\f[R] If \f[B]x\f[R] is not equal to \f[B]0\f[R] and greater that \f[B]-1\f[R] and less than \f[B]1\f[R], it is printed without a leading zero, regardless of the use of the \f[B]-z\f[R] option (see the \f[B]OPTIONS\f[R] section) and with a trailing newline. .RS .PP Otherwise, \f[B]x\f[R] is printed normally, with a trailing newline. .RE .TP \f[B]ubytes(x)\f[R] Returns the numbers of unsigned integer bytes required to hold the truncated absolute value of \f[B]x\f[R]. .TP \f[B]sbytes(x)\f[R] Returns the numbers of signed, two\[cq]s-complement integer bytes required to hold the truncated value of \f[B]x\f[R]. .TP \f[B]s2u(x)\f[R] Returns \f[B]x\f[R] if it is non-negative. If it \f[I]is\f[R] negative, then it calculates what \f[B]x\f[R] would be as a 2\[cq]s-complement signed integer and returns the non-negative integer that would have the same representation in binary. .TP \f[B]s2un(x,n)\f[R] Returns \f[B]x\f[R] if it is non-negative. If it \f[I]is\f[R] negative, then it calculates what \f[B]x\f[R] would be as a 2\[cq]s-complement signed integer with \f[B]n\f[R] bytes and returns the non-negative integer that would have the same representation in binary. If \f[B]x\f[R] cannot fit into \f[B]n\f[R] 2\[cq]s-complement signed bytes, it is truncated to fit. .TP \f[B]hex(x)\f[R] Outputs the hexadecimal (base \f[B]16\f[R]) representation of \f[B]x\f[R]. .RS .PP This is a \f[B]void\f[R] function (see the \f[I]Void Functions\f[R] subsection of the \f[B]FUNCTIONS\f[R] section). .RE .TP \f[B]binary(x)\f[R] Outputs the binary (base \f[B]2\f[R]) representation of \f[B]x\f[R]. .RS .PP This is a \f[B]void\f[R] function (see the \f[I]Void Functions\f[R] subsection of the \f[B]FUNCTIONS\f[R] section). .RE .TP \f[B]output(x, b)\f[R] Outputs the base \f[B]b\f[R] representation of \f[B]x\f[R]. .RS .PP This is a \f[B]void\f[R] function (see the \f[I]Void Functions\f[R] subsection of the \f[B]FUNCTIONS\f[R] section). .RE .TP \f[B]uint(x)\f[R] Outputs the representation, in binary and hexadecimal, of \f[B]x\f[R] as an unsigned integer in as few power of two bytes as possible. Both outputs are split into bytes separated by spaces. .RS .PP If \f[B]x\f[R] is not an integer or is negative, an error message is printed instead, but bc(1) is not reset (see the \f[B]RESET\f[R] section). .PP This is a \f[B]void\f[R] function (see the \f[I]Void Functions\f[R] subsection of the \f[B]FUNCTIONS\f[R] section). .RE .TP \f[B]int(x)\f[R] Outputs the representation, in binary and hexadecimal, of \f[B]x\f[R] as a signed, two\[cq]s-complement integer in as few power of two bytes as possible. Both outputs are split into bytes separated by spaces. .RS .PP If \f[B]x\f[R] is not an integer, an error message is printed instead, but bc(1) is not reset (see the \f[B]RESET\f[R] section). .PP This is a \f[B]void\f[R] function (see the \f[I]Void Functions\f[R] subsection of the \f[B]FUNCTIONS\f[R] section). .RE .TP \f[B]uintn(x, n)\f[R] Outputs the representation, in binary and hexadecimal, of \f[B]x\f[R] as an unsigned integer in \f[B]n\f[R] bytes. Both outputs are split into bytes separated by spaces. .RS .PP If \f[B]x\f[R] is not an integer, is negative, or cannot fit into \f[B]n\f[R] bytes, an error message is printed instead, but bc(1) is not reset (see the \f[B]RESET\f[R] section). .PP This is a \f[B]void\f[R] function (see the \f[I]Void Functions\f[R] subsection of the \f[B]FUNCTIONS\f[R] section). .RE .TP \f[B]intn(x, n)\f[R] Outputs the representation, in binary and hexadecimal, of \f[B]x\f[R] as a signed, two\[cq]s-complement integer in \f[B]n\f[R] bytes. Both outputs are split into bytes separated by spaces. .RS .PP If \f[B]x\f[R] is not an integer or cannot fit into \f[B]n\f[R] bytes, an error message is printed instead, but bc(1) is not reset (see the \f[B]RESET\f[R] section). .PP This is a \f[B]void\f[R] function (see the \f[I]Void Functions\f[R] subsection of the \f[B]FUNCTIONS\f[R] section). .RE .TP \f[B]uint8(x)\f[R] Outputs the representation, in binary and hexadecimal, of \f[B]x\f[R] as an unsigned integer in \f[B]1\f[R] byte. Both outputs are split into bytes separated by spaces. .RS .PP If \f[B]x\f[R] is not an integer, is negative, or cannot fit into \f[B]1\f[R] byte, an error message is printed instead, but bc(1) is not reset (see the \f[B]RESET\f[R] section). .PP This is a \f[B]void\f[R] function (see the \f[I]Void Functions\f[R] subsection of the \f[B]FUNCTIONS\f[R] section). .RE .TP \f[B]int8(x)\f[R] Outputs the representation, in binary and hexadecimal, of \f[B]x\f[R] as a signed, two\[cq]s-complement integer in \f[B]1\f[R] byte. Both outputs are split into bytes separated by spaces. .RS .PP If \f[B]x\f[R] is not an integer or cannot fit into \f[B]1\f[R] byte, an error message is printed instead, but bc(1) is not reset (see the \f[B]RESET\f[R] section). .PP This is a \f[B]void\f[R] function (see the \f[I]Void Functions\f[R] subsection of the \f[B]FUNCTIONS\f[R] section). .RE .TP \f[B]uint16(x)\f[R] Outputs the representation, in binary and hexadecimal, of \f[B]x\f[R] as an unsigned integer in \f[B]2\f[R] bytes. Both outputs are split into bytes separated by spaces. .RS .PP If \f[B]x\f[R] is not an integer, is negative, or cannot fit into \f[B]2\f[R] bytes, an error message is printed instead, but bc(1) is not reset (see the \f[B]RESET\f[R] section). .PP This is a \f[B]void\f[R] function (see the \f[I]Void Functions\f[R] subsection of the \f[B]FUNCTIONS\f[R] section). .RE .TP \f[B]int16(x)\f[R] Outputs the representation, in binary and hexadecimal, of \f[B]x\f[R] as a signed, two\[cq]s-complement integer in \f[B]2\f[R] bytes. Both outputs are split into bytes separated by spaces. .RS .PP If \f[B]x\f[R] is not an integer or cannot fit into \f[B]2\f[R] bytes, an error message is printed instead, but bc(1) is not reset (see the \f[B]RESET\f[R] section). .PP This is a \f[B]void\f[R] function (see the \f[I]Void Functions\f[R] subsection of the \f[B]FUNCTIONS\f[R] section). .RE .TP \f[B]uint32(x)\f[R] Outputs the representation, in binary and hexadecimal, of \f[B]x\f[R] as an unsigned integer in \f[B]4\f[R] bytes. Both outputs are split into bytes separated by spaces. .RS .PP If \f[B]x\f[R] is not an integer, is negative, or cannot fit into \f[B]4\f[R] bytes, an error message is printed instead, but bc(1) is not reset (see the \f[B]RESET\f[R] section). .PP This is a \f[B]void\f[R] function (see the \f[I]Void Functions\f[R] subsection of the \f[B]FUNCTIONS\f[R] section). .RE .TP \f[B]int32(x)\f[R] Outputs the representation, in binary and hexadecimal, of \f[B]x\f[R] as a signed, two\[cq]s-complement integer in \f[B]4\f[R] bytes. Both outputs are split into bytes separated by spaces. .RS .PP If \f[B]x\f[R] is not an integer or cannot fit into \f[B]4\f[R] bytes, an error message is printed instead, but bc(1) is not reset (see the \f[B]RESET\f[R] section). .PP This is a \f[B]void\f[R] function (see the \f[I]Void Functions\f[R] subsection of the \f[B]FUNCTIONS\f[R] section). .RE .TP \f[B]uint64(x)\f[R] Outputs the representation, in binary and hexadecimal, of \f[B]x\f[R] as an unsigned integer in \f[B]8\f[R] bytes. Both outputs are split into bytes separated by spaces. .RS .PP If \f[B]x\f[R] is not an integer, is negative, or cannot fit into \f[B]8\f[R] bytes, an error message is printed instead, but bc(1) is not reset (see the \f[B]RESET\f[R] section). .PP This is a \f[B]void\f[R] function (see the \f[I]Void Functions\f[R] subsection of the \f[B]FUNCTIONS\f[R] section). .RE .TP \f[B]int64(x)\f[R] Outputs the representation, in binary and hexadecimal, of \f[B]x\f[R] as a signed, two\[cq]s-complement integer in \f[B]8\f[R] bytes. Both outputs are split into bytes separated by spaces. .RS .PP If \f[B]x\f[R] is not an integer or cannot fit into \f[B]8\f[R] bytes, an error message is printed instead, but bc(1) is not reset (see the \f[B]RESET\f[R] section). .PP This is a \f[B]void\f[R] function (see the \f[I]Void Functions\f[R] subsection of the \f[B]FUNCTIONS\f[R] section). .RE .TP \f[B]hex_uint(x, n)\f[R] Outputs the representation of the truncated absolute value of \f[B]x\f[R] as an unsigned integer in hexadecimal using \f[B]n\f[R] bytes. Not all of the value will be output if \f[B]n\f[R] is too small. .RS .PP This is a \f[B]void\f[R] function (see the \f[I]Void Functions\f[R] subsection of the \f[B]FUNCTIONS\f[R] section). .RE .TP \f[B]binary_uint(x, n)\f[R] Outputs the representation of the truncated absolute value of \f[B]x\f[R] as an unsigned integer in binary using \f[B]n\f[R] bytes. Not all of the value will be output if \f[B]n\f[R] is too small. .RS .PP This is a \f[B]void\f[R] function (see the \f[I]Void Functions\f[R] subsection of the \f[B]FUNCTIONS\f[R] section). .RE .TP \f[B]output_uint(x, n)\f[R] Outputs the representation of the truncated absolute value of \f[B]x\f[R] as an unsigned integer in the current \f[B]obase\f[R] (see the \f[B]SYNTAX\f[R] section) using \f[B]n\f[R] bytes. Not all of the value will be output if \f[B]n\f[R] is too small. .RS .PP This is a \f[B]void\f[R] function (see the \f[I]Void Functions\f[R] subsection of the \f[B]FUNCTIONS\f[R] section). .RE .TP \f[B]output_byte(x, i)\f[R] Outputs byte \f[B]i\f[R] of the truncated absolute value of \f[B]x\f[R], where \f[B]0\f[R] is the least significant byte and \f[B]number_of_bytes - 1\f[R] is the most significant byte. .RS .PP This is a \f[B]void\f[R] function (see the \f[I]Void Functions\f[R] subsection of the \f[B]FUNCTIONS\f[R] section). .RE .SS Transcendental Functions .PP All transcendental functions can return slightly inaccurate results (up to 1 ULP (https://en.wikipedia.org/wiki/Unit_in_the_last_place)). This is unavoidable, and this article (https://people.eecs.berkeley.edu/~wkahan/LOG10HAF.TXT) explains why it is impossible and unnecessary to calculate exact results for the transcendental functions. .PP Because of the possible inaccuracy, I recommend that users call those functions with the precision (\f[B]scale\f[R]) set to at least 1 higher than is necessary. If exact results are \f[I]absolutely\f[R] required, users can double the precision (\f[B]scale\f[R]) and then truncate. .PP The transcendental functions in the standard math library are: .IP \[bu] 2 \f[B]s(x)\f[R] .IP \[bu] 2 \f[B]c(x)\f[R] .IP \[bu] 2 \f[B]a(x)\f[R] .IP \[bu] 2 \f[B]l(x)\f[R] .IP \[bu] 2 \f[B]e(x)\f[R] .IP \[bu] 2 \f[B]j(x, n)\f[R] .PP The transcendental functions in the extended math library are: .IP \[bu] 2 \f[B]l2(x)\f[R] .IP \[bu] 2 \f[B]l10(x)\f[R] .IP \[bu] 2 \f[B]log(x, b)\f[R] .IP \[bu] 2 \f[B]pi(p)\f[R] .IP \[bu] 2 \f[B]t(x)\f[R] .IP \[bu] 2 \f[B]a2(y, x)\f[R] .IP \[bu] 2 \f[B]sin(x)\f[R] .IP \[bu] 2 \f[B]cos(x)\f[R] .IP \[bu] 2 \f[B]tan(x)\f[R] .IP \[bu] 2 \f[B]atan(x)\f[R] .IP \[bu] 2 \f[B]atan2(y, x)\f[R] .IP \[bu] 2 \f[B]r2d(x)\f[R] .IP \[bu] 2 \f[B]d2r(x)\f[R] .SH RESET .PP When bc(1) encounters an error or a signal that it has a non-default handler for, it resets. This means that several things happen. .PP First, any functions that are executing are stopped and popped off the stack. The behavior is not unlike that of exceptions in programming languages. Then the execution point is set so that any code waiting to execute (after all functions returned) is skipped. .PP Thus, when bc(1) resets, it skips any remaining code waiting to be executed. Then, if it is interactive mode, and the error was not a fatal error (see the \f[B]EXIT STATUS\f[R] section), it asks for more input; otherwise, it exits with the appropriate return code. .PP Note that this reset behavior is different from the GNU bc(1), which attempts to start executing the statement right after the one that caused an error. .SH PERFORMANCE .PP Most bc(1) implementations use \f[B]char\f[R] types to calculate the value of \f[B]1\f[R] decimal digit at a time, but that can be slow. This bc(1) does something different. .PP It uses large integers to calculate more than \f[B]1\f[R] decimal digit at a time. If built in a environment where \f[B]BC_LONG_BIT\f[R] (see the \f[B]LIMITS\f[R] section) is \f[B]64\f[R], then each integer has \f[B]9\f[R] decimal digits. If built in an environment where \f[B]BC_LONG_BIT\f[R] is \f[B]32\f[R] then each integer has \f[B]4\f[R] decimal digits. This value (the number of decimal digits per large integer) is called \f[B]BC_BASE_DIGS\f[R]. .PP The actual values of \f[B]BC_LONG_BIT\f[R] and \f[B]BC_BASE_DIGS\f[R] can be queried with the \f[B]limits\f[R] statement. .PP In addition, this bc(1) uses an even larger integer for overflow checking. This integer type depends on the value of \f[B]BC_LONG_BIT\f[R], but is always at least twice as large as the integer type used to store digits. .SH LIMITS .PP The following are the limits on bc(1): .TP \f[B]BC_LONG_BIT\f[R] The number of bits in the \f[B]long\f[R] type in the environment where bc(1) was built. This determines how many decimal digits can be stored in a single large integer (see the \f[B]PERFORMANCE\f[R] section). .TP \f[B]BC_BASE_DIGS\f[R] The number of decimal digits per large integer (see the \f[B]PERFORMANCE\f[R] section). Depends on \f[B]BC_LONG_BIT\f[R]. .TP \f[B]BC_BASE_POW\f[R] The max decimal number that each large integer can store (see \f[B]BC_BASE_DIGS\f[R]) plus \f[B]1\f[R]. Depends on \f[B]BC_BASE_DIGS\f[R]. .TP \f[B]BC_OVERFLOW_MAX\f[R] The max number that the overflow type (see the \f[B]PERFORMANCE\f[R] section) can hold. Depends on \f[B]BC_LONG_BIT\f[R]. .TP \f[B]BC_BASE_MAX\f[R] The maximum output base. Set at \f[B]BC_BASE_POW\f[R]. .TP \f[B]BC_DIM_MAX\f[R] The maximum size of arrays. Set at \f[B]SIZE_MAX-1\f[R]. .TP \f[B]BC_SCALE_MAX\f[R] The maximum \f[B]scale\f[R]. Set at \f[B]BC_OVERFLOW_MAX-1\f[R]. .TP \f[B]BC_STRING_MAX\f[R] The maximum length of strings. Set at \f[B]BC_OVERFLOW_MAX-1\f[R]. .TP \f[B]BC_NAME_MAX\f[R] The maximum length of identifiers. Set at \f[B]BC_OVERFLOW_MAX-1\f[R]. .TP \f[B]BC_NUM_MAX\f[R] The maximum length of a number (in decimal digits), which includes digits after the decimal point. Set at \f[B]BC_OVERFLOW_MAX-1\f[R]. .TP \f[B]BC_RAND_MAX\f[R] The maximum integer (inclusive) returned by the \f[B]rand()\f[R] operand. Set at \f[B]2\[ha]BC_LONG_BIT-1\f[R]. .TP Exponent The maximum allowable exponent (positive or negative). Set at \f[B]BC_OVERFLOW_MAX\f[R]. .TP Number of vars The maximum number of vars/arrays. Set at \f[B]SIZE_MAX-1\f[R]. .PP The actual values can be queried with the \f[B]limits\f[R] statement. .PP These limits are meant to be effectively non-existent; the limits are so large (at least on 64-bit machines) that there should not be any point at which they become a problem. In fact, memory should be exhausted before these limits should be hit. .SH ENVIRONMENT VARIABLES .PP bc(1) recognizes the following environment variables: .TP \f[B]POSIXLY_CORRECT\f[R] If this variable exists (no matter the contents), bc(1) behaves as if the \f[B]-s\f[R] option was given. .TP \f[B]BC_ENV_ARGS\f[R] This is another way to give command-line arguments to bc(1). They should be in the same format as all other command-line arguments. These are always processed first, so any files given in \f[B]BC_ENV_ARGS\f[R] will be processed before arguments and files given on the command-line. This gives the user the ability to set up \[lq]standard\[rq] options and files to be used at every invocation. The most useful thing for such files to contain would be useful functions that the user might want every time bc(1) runs. .RS .PP The code that parses \f[B]BC_ENV_ARGS\f[R] will correctly handle quoted arguments, but it does not understand escape sequences. For example, the string \f[B]\[lq]/home/gavin/some bc file.bc\[rq]\f[R] will be correctly parsed, but the string \f[B]\[lq]/home/gavin/some \[dq]bc\[dq] file.bc\[rq]\f[R] will include the backslashes. .PP The quote parsing will handle either kind of quotes, \f[B]\[cq]\f[R] or \f[B]\[lq]\f[R]. Thus, if you have a file with any number of single quotes in the name, you can use double quotes as the outside quotes, as in \f[B]\[lq]some `bc' file.bc\[rq]\f[R], and vice versa if you have a file with double quotes. However, handling a file with both kinds of quotes in \f[B]BC_ENV_ARGS\f[R] is not supported due to the complexity of the parsing, though such files are still supported on the command-line where the parsing is done by the shell. .RE .TP \f[B]BC_LINE_LENGTH\f[R] If this environment variable exists and contains an integer that is greater than \f[B]1\f[R] and is less than \f[B]UINT16_MAX\f[R] (\f[B]2\[ha]16-1\f[R]), bc(1) will output lines to that length, including the backslash (\f[B]\[rs]\f[R]). The default line length is \f[B]70\f[R]. .RS .PP The special value of \f[B]0\f[R] will disable line length checking and print numbers without regard to line length and without backslashes and newlines. .RE .TP \f[B]BC_BANNER\f[R] If this environment variable exists and contains an integer, then a non-zero value activates the copyright banner when bc(1) is in interactive mode, while zero deactivates it. .RS .PP If bc(1) is not in interactive mode (see the \f[B]INTERACTIVE MODE\f[R] section), then this environment variable has no effect because bc(1) does not print the banner when not in interactive mode. .PP This environment variable overrides the default, which can be queried with the \f[B]-h\f[R] or \f[B]--help\f[R] options. .RE .TP \f[B]BC_SIGINT_RESET\f[R] If bc(1) is not in interactive mode (see the \f[B]INTERACTIVE MODE\f[R] section), then this environment variable has no effect because bc(1) exits on \f[B]SIGINT\f[R] when not in interactive mode. .RS .PP However, when bc(1) is in interactive mode, then if this environment variable exists and contains an integer, a non-zero value makes bc(1) reset on \f[B]SIGINT\f[R], rather than exit, and zero makes bc(1) exit. If this environment variable exists and is \f[I]not\f[R] an integer, then bc(1) will exit on \f[B]SIGINT\f[R]. .PP This environment variable overrides the default, which can be queried with the \f[B]-h\f[R] or \f[B]--help\f[R] options. .RE .TP \f[B]BC_TTY_MODE\f[R] If TTY mode is \f[I]not\f[R] available (see the \f[B]TTY MODE\f[R] section), then this environment variable has no effect. .RS .PP However, when TTY mode is available, then if this environment variable exists and contains an integer, then a non-zero value makes bc(1) use TTY mode, and zero makes bc(1) not use TTY mode. .PP This environment variable overrides the default, which can be queried with the \f[B]-h\f[R] or \f[B]--help\f[R] options. .RE .TP \f[B]BC_PROMPT\f[R] If TTY mode is \f[I]not\f[R] available (see the \f[B]TTY MODE\f[R] section), then this environment variable has no effect. .RS .PP However, when TTY mode is available, then if this environment variable exists and contains an integer, a non-zero value makes bc(1) use a prompt, and zero or a non-integer makes bc(1) not use a prompt. If this environment variable does not exist and \f[B]BC_TTY_MODE\f[R] does, then the value of the \f[B]BC_TTY_MODE\f[R] environment variable is used. .PP This environment variable and the \f[B]BC_TTY_MODE\f[R] environment variable override the default, which can be queried with the \f[B]-h\f[R] or \f[B]--help\f[R] options. .RE +.TP +\f[B]BC_EXPR_EXIT\f[R] +If any expressions or expression files are given on the command-line +with \f[B]-e\f[R], \f[B]--expression\f[R], \f[B]-f\f[R], or +\f[B]--file\f[R], then if this environment variable exists and contains +an integer, a non-zero value makes bc(1) exit after executing the +expressions and expression files, and a non-zero value makes bc(1) not +exit. +.RS +.PP +This environment variable overrides the default, which can be queried +with the \f[B]-h\f[R] or \f[B]--help\f[R] options. +.RE .SH EXIT STATUS .PP bc(1) returns the following exit statuses: .TP \f[B]0\f[R] No error. .TP \f[B]1\f[R] A math error occurred. This follows standard practice of using \f[B]1\f[R] for expected errors, since math errors will happen in the process of normal execution. .RS .PP Math errors include divide by \f[B]0\f[R], taking the square root of a negative number, using a negative number as a bound for the pseudo-random number generator, attempting to convert a negative number to a hardware integer, overflow when converting a number to a hardware integer, overflow when calculating the size of a number, and attempting to use a non-integer where an integer is required. .PP Converting to a hardware integer happens for the second operand of the power (\f[B]\[ha]\f[R]), places (\f[B]\[at]\f[R]), left shift (\f[B]<<\f[R]), and right shift (\f[B]>>\f[R]) operators and their corresponding assignment operators. .RE .TP \f[B]2\f[R] A parse error occurred. .RS .PP Parse errors include unexpected \f[B]EOF\f[R], using an invalid character, failing to find the end of a string or comment, using a token where it is invalid, giving an invalid expression, giving an invalid print statement, giving an invalid function definition, attempting to assign to an expression that is not a named expression (see the \f[I]Named Expressions\f[R] subsection of the \f[B]SYNTAX\f[R] section), giving an invalid \f[B]auto\f[R] list, having a duplicate \f[B]auto\f[R]/function parameter, failing to find the end of a code block, attempting to return a value from a \f[B]void\f[R] function, attempting to use a variable as a reference, and using any extensions when the option \f[B]-s\f[R] or any equivalents were given. .RE .TP \f[B]3\f[R] A runtime error occurred. .RS .PP Runtime errors include assigning an invalid number to any global (\f[B]ibase\f[R], \f[B]obase\f[R], or \f[B]scale\f[R]), giving a bad expression to a \f[B]read()\f[R] call, calling \f[B]read()\f[R] inside of a \f[B]read()\f[R] call, type errors, passing the wrong number of arguments to functions, attempting to call an undefined function, and attempting to use a \f[B]void\f[R] function call as a value in an expression. .RE .TP \f[B]4\f[R] A fatal error occurred. .RS .PP Fatal errors include memory allocation errors, I/O errors, failing to open files, attempting to use files that do not have only ASCII characters (bc(1) only accepts ASCII characters), attempting to open a directory as a file, and giving invalid command-line options. .RE .PP The exit status \f[B]4\f[R] is special; when a fatal error occurs, bc(1) always exits and returns \f[B]4\f[R], no matter what mode bc(1) is in. .PP The other statuses will only be returned when bc(1) is not in interactive mode (see the \f[B]INTERACTIVE MODE\f[R] section), since bc(1) resets its state (see the \f[B]RESET\f[R] section) and accepts more input when one of those errors occurs in interactive mode. This is also the case when interactive mode is forced by the \f[B]-i\f[R] flag or \f[B]--interactive\f[R] option. .PP These exit statuses allow bc(1) to be used in shell scripting with error checking, and its normal behavior can be forced by using the \f[B]-i\f[R] flag or \f[B]--interactive\f[R] option. .SH INTERACTIVE MODE .PP Per the standard (https://pubs.opengroup.org/onlinepubs/9699919799/utilities/bc.html), bc(1) has an interactive mode and a non-interactive mode. Interactive mode is turned on automatically when both \f[B]stdin\f[R] and \f[B]stdout\f[R] are hooked to a terminal, but the \f[B]-i\f[R] flag and \f[B]--interactive\f[R] option can turn it on in other situations. .PP In interactive mode, bc(1) attempts to recover from errors (see the \f[B]RESET\f[R] section), and in normal execution, flushes \f[B]stdout\f[R] as soon as execution is done for the current input. bc(1) may also reset on \f[B]SIGINT\f[R] instead of exit, depending on the contents of, or default for, the \f[B]BC_SIGINT_RESET\f[R] environment variable (see the \f[B]ENVIRONMENT VARIABLES\f[R] section). .SH TTY MODE .PP If \f[B]stdin\f[R], \f[B]stdout\f[R], and \f[B]stderr\f[R] are all connected to a TTY, then \[lq]TTY mode\[rq] is considered to be available, and thus, bc(1) can turn on TTY mode, subject to some settings. .PP If there is the environment variable \f[B]BC_TTY_MODE\f[R] in the environment (see the \f[B]ENVIRONMENT VARIABLES\f[R] section), then if that environment variable contains a non-zero integer, bc(1) will turn on TTY mode when \f[B]stdin\f[R], \f[B]stdout\f[R], and \f[B]stderr\f[R] are all connected to a TTY. If the \f[B]BC_TTY_MODE\f[R] environment variable exists but is \f[I]not\f[R] a non-zero integer, then bc(1) will not turn TTY mode on. .PP If the environment variable \f[B]BC_TTY_MODE\f[R] does \f[I]not\f[R] exist, the default setting is used. The default setting can be queried with the \f[B]-h\f[R] or \f[B]--help\f[R] options. .PP TTY mode is different from interactive mode because interactive mode is required in the bc(1) specification (https://pubs.opengroup.org/onlinepubs/9699919799/utilities/bc.html), and interactive mode requires only \f[B]stdin\f[R] and \f[B]stdout\f[R] to be connected to a terminal. .SS Command-Line History .PP Command-line history is only enabled if TTY mode is, i.e., that \f[B]stdin\f[R], \f[B]stdout\f[R], and \f[B]stderr\f[R] are connected to a TTY and the \f[B]BC_TTY_MODE\f[R] environment variable (see the \f[B]ENVIRONMENT VARIABLES\f[R] section) and its default do not disable TTY mode. See the \f[B]COMMAND LINE HISTORY\f[R] section for more information. .SS Prompt .PP If TTY mode is available, then a prompt can be enabled. Like TTY mode itself, it can be turned on or off with an environment variable: \f[B]BC_PROMPT\f[R] (see the \f[B]ENVIRONMENT VARIABLES\f[R] section). .PP If the environment variable \f[B]BC_PROMPT\f[R] exists and is a non-zero integer, then the prompt is turned on when \f[B]stdin\f[R], \f[B]stdout\f[R], and \f[B]stderr\f[R] are connected to a TTY and the \f[B]-P\f[R] and \f[B]--no-prompt\f[R] options were not used. The read prompt will be turned on under the same conditions, except that the \f[B]-R\f[R] and \f[B]--no-read-prompt\f[R] options must also not be used. .PP However, if \f[B]BC_PROMPT\f[R] does not exist, the prompt can be enabled or disabled with the \f[B]BC_TTY_MODE\f[R] environment variable, the \f[B]-P\f[R] and \f[B]--no-prompt\f[R] options, and the \f[B]-R\f[R] and \f[B]--no-read-prompt\f[R] options. See the \f[B]ENVIRONMENT VARIABLES\f[R] and \f[B]OPTIONS\f[R] sections for more details. .SH SIGNAL HANDLING .PP Sending a \f[B]SIGINT\f[R] will cause bc(1) to do one of two things. .PP If bc(1) is not in interactive mode (see the \f[B]INTERACTIVE MODE\f[R] section), or the \f[B]BC_SIGINT_RESET\f[R] environment variable (see the \f[B]ENVIRONMENT VARIABLES\f[R] section), or its default, is either not an integer or it is zero, bc(1) will exit. .PP However, if bc(1) is in interactive mode, and the \f[B]BC_SIGINT_RESET\f[R] or its default is an integer and non-zero, then bc(1) will stop executing the current input and reset (see the \f[B]RESET\f[R] section) upon receiving a \f[B]SIGINT\f[R]. .PP Note that \[lq]current input\[rq] can mean one of two things. If bc(1) is processing input from \f[B]stdin\f[R] in interactive mode, it will ask for more input. If bc(1) is processing input from a file in interactive mode, it will stop processing the file and start processing the next file, if one exists, or ask for input from \f[B]stdin\f[R] if no other file exists. .PP This means that if a \f[B]SIGINT\f[R] is sent to bc(1) as it is executing a file, it can seem as though bc(1) did not respond to the signal since it will immediately start executing the next file. This is by design; most files that users execute when interacting with bc(1) have function definitions, which are quick to parse. If a file takes a long time to execute, there may be a bug in that file. The rest of the files could still be executed without problem, allowing the user to continue. .PP \f[B]SIGTERM\f[R] and \f[B]SIGQUIT\f[R] cause bc(1) to clean up and exit, and it uses the default handler for all other signals. The one exception is \f[B]SIGHUP\f[R]; in that case, and only when bc(1) is in TTY mode (see the \f[B]TTY MODE\f[R] section), a \f[B]SIGHUP\f[R] will cause bc(1) to clean up and exit. .SH COMMAND LINE HISTORY .PP bc(1) supports interactive command-line editing. .PP If bc(1) can be in TTY mode (see the \f[B]TTY MODE\f[R] section), history can be enabled. This means that command-line history can only be enabled when \f[B]stdin\f[R], \f[B]stdout\f[R], and \f[B]stderr\f[R] are all connected to a TTY. .PP Like TTY mode itself, it can be turned on or off with the environment variable \f[B]BC_TTY_MODE\f[R] (see the \f[B]ENVIRONMENT VARIABLES\f[R] section). .PP If history is enabled, previous lines can be recalled and edited with the arrow keys. .PP \f[B]Note\f[R]: tabs are converted to 8 spaces. .SH LOCALES .PP This bc(1) ships with support for adding error messages for different locales and thus, supports \f[B]LC_MESSAGES\f[R]. .SH SEE ALSO .PP dc(1) .SH STANDARDS .PP bc(1) is compliant with the IEEE Std 1003.1-2017 (\[lq]POSIX.1-2017\[rq]) (https://pubs.opengroup.org/onlinepubs/9699919799/utilities/bc.html) specification. The flags \f[B]-efghiqsvVw\f[R], all long options, and the extensions noted above are extensions to that specification. .PP Note that the specification explicitly says that bc(1) only accepts numbers that use a period (\f[B].\f[R]) as a radix point, regardless of the value of \f[B]LC_NUMERIC\f[R]. .PP This bc(1) supports error messages for different locales, and thus, it supports \f[B]LC_MESSAGES\f[R]. .SH BUGS .PP None are known. Report bugs at https://git.yzena.com/gavin/bc. .SH AUTHORS .PP Gavin D. Howard and contributors. diff --git a/contrib/bc/manuals/bc/A.1.md b/contrib/bc/manuals/bc/A.1.md index e773d967284c..112e98078cf0 100644 --- a/contrib/bc/manuals/bc/A.1.md +++ b/contrib/bc/manuals/bc/A.1.md @@ -1,2347 +1,2358 @@ # NAME bc - arbitrary-precision decimal arithmetic language and calculator # SYNOPSIS **bc** [**-ghilPqRsvVw**] [**-\-global-stacks**] [**-\-help**] [**-\-interactive**] [**-\-mathlib**] [**-\-no-prompt**] [**-\-no-read-prompt**] [**-\-quiet**] [**-\-standard**] [**-\-warn**] [**-\-version**] [**-e** *expr*] [**-\-expression**=*expr*...] [**-f** *file*...] [**-\-file**=*file*...] [*file*...] # DESCRIPTION bc(1) is an interactive processor for a language first standardized in 1991 by POSIX. (The current standard is [here][1].) The language provides unlimited precision decimal arithmetic and is somewhat C-like, but there are differences. Such differences will be noted in this document. After parsing and handling options, this bc(1) reads any files given on the command line and executes them before reading from **stdin**. This bc(1) is a drop-in replacement for *any* bc(1), including (and especially) the GNU bc(1). It also has many extensions and extra features beyond other implementations. **Note**: If running this bc(1) on *any* script meant for another bc(1) gives a parse error, it is probably because a word this bc(1) reserves as a keyword is used as the name of a function, variable, or array. To fix that, use the command-line option **-r** *keyword*, where *keyword* is the keyword that is used as a name in the script. For more information, see the **OPTIONS** section. If parsing scripts meant for other bc(1) implementations still does not work, that is a bug and should be reported. See the **BUGS** section. # OPTIONS The following are the options that bc(1) accepts. **-g**, **-\-global-stacks** : Turns the globals **ibase**, **obase**, **scale**, and **seed** into stacks. This has the effect that a copy of the current value of all four are pushed onto a stack for every function call, as well as popped when every function returns. This means that functions can assign to any and all of those globals without worrying that the change will affect other functions. Thus, a hypothetical function named **output(x,b)** that simply printed **x** in base **b** could be written like this: define void output(x, b) { obase=b x } instead of like this: define void output(x, b) { auto c c=obase obase=b x obase=c } This makes writing functions much easier. (**Note**: the function **output(x,b)** exists in the extended math library. See the **LIBRARY** section.) However, since using this flag means that functions cannot set **ibase**, **obase**, **scale**, or **seed** globally, functions that are made to do so cannot work anymore. There are two possible use cases for that, and each has a solution. First, if a function is called on startup to turn bc(1) into a number converter, it is possible to replace that capability with various shell aliases. Examples: alias d2o="bc -e ibase=A -e obase=8" alias h2b="bc -e ibase=G -e obase=2" Second, if the purpose of a function is to set **ibase**, **obase**, **scale**, or **seed** globally for any other purpose, it could be split into one to four functions (based on how many globals it sets) and each of those functions could return the desired value for a global. For functions that set **seed**, the value assigned to **seed** is not propagated to parent functions. This means that the sequence of pseudo-random numbers that they see will not be the same sequence of pseudo-random numbers that any parent sees. This is only the case once **seed** has been set. If a function desires to not affect the sequence of pseudo-random numbers of its parents, but wants to use the same **seed**, it can use the following line: seed = seed If the behavior of this option is desired for every run of bc(1), then users could make sure to define **BC_ENV_ARGS** and include this option (see the **ENVIRONMENT VARIABLES** section for more details). If **-s**, **-w**, or any equivalents are used, this option is ignored. This is a **non-portable extension**. **-h**, **-\-help** : Prints a usage message and quits. **-i**, **-\-interactive** : Forces interactive mode. (See the **INTERACTIVE MODE** section.) This is a **non-portable extension**. **-L**, **-\-no-line-length** : Disables line length checking and prints numbers without backslashes and newlines. In other words, this option sets **BC_LINE_LENGTH** to **0** (see the **ENVIRONMENT VARIABLES** section). This is a **non-portable extension**. **-l**, **-\-mathlib** : Sets **scale** (see the **SYNTAX** section) to **20** and loads the included math library and the extended math library before running any code, including any expressions or files specified on the command line. To learn what is in the libraries, see the **LIBRARY** section. **-P**, **-\-no-prompt** : Disables the prompt in TTY mode. (The prompt is only enabled in TTY mode. See the **TTY MODE** section.) This is mostly for those users that do not want a prompt or are not used to having them in bc(1). Most of those users would want to put this option in **BC_ENV_ARGS** (see the **ENVIRONMENT VARIABLES** section). These options override the **BC_PROMPT** and **BC_TTY_MODE** environment variables (see the **ENVIRONMENT VARIABLES** section). This is a **non-portable extension**. **-R**, **-\-no-read-prompt** : Disables the read prompt in TTY mode. (The read prompt is only enabled in TTY mode. See the **TTY MODE** section.) This is mostly for those users that do not want a read prompt or are not used to having them in bc(1). Most of those users would want to put this option in **BC_ENV_ARGS** (see the **ENVIRONMENT VARIABLES** section). This option is also useful in hash bang lines of bc(1) scripts that prompt for user input. This option does not disable the regular prompt because the read prompt is only used when the **read()** built-in function is called. These options *do* override the **BC_PROMPT** and **BC_TTY_MODE** environment variables (see the **ENVIRONMENT VARIABLES** section), but only for the read prompt. This is a **non-portable extension**. **-r** *keyword*, **-\-redefine**=*keyword* : Redefines *keyword* in order to allow it to be used as a function, variable, or array name. This is useful when this bc(1) gives parse errors when parsing scripts meant for other bc(1) implementations. The keywords this bc(1) allows to be redefined are: * **abs** * **asciify** * **continue** * **divmod** * **else** * **halt** * **irand** * **last** * **limits** * **maxibase** * **maxobase** * **maxrand** * **maxscale** * **modexp** * **print** * **rand** * **read** * **seed** * **stream** If any of those keywords are used as a function, variable, or array name in a script, use this option with the keyword as the argument. If multiple are used, use this option for all of them; it can be used multiple times. Keywords are *not* redefined when parsing the builtin math library (see the **LIBRARY** section). It is a fatal error to redefine keywords mandated by the POSIX standard. It is a fatal error to attempt to redefine words that this bc(1) does not reserve as keywords. **-q**, **-\-quiet** : This option is for compatibility with the [GNU bc(1)][2]; it is a no-op. Without this option, GNU bc(1) prints a copyright header. This bc(1) only prints the copyright header if one or more of the **-v**, **-V**, or **-\-version** options are given. This is a **non-portable extension**. **-s**, **-\-standard** : Process exactly the language defined by the [standard][1] and error if any extensions are used. This is a **non-portable extension**. **-v**, **-V**, **-\-version** : Print the version information (copyright header) and exit. This is a **non-portable extension**. **-w**, **-\-warn** : Like **-s** and **-\-standard**, except that warnings (and not errors) are printed for non-standard extensions and execution continues normally. This is a **non-portable extension**. **-z**, **-\-leading-zeroes** : Makes bc(1) print all numbers greater than **-1** and less than **1**, and not equal to **0**, with a leading zero. This can be set for individual numbers with the **plz(x)**, plznl(x)**, **pnlz(x)**, and **pnlznl(x)** functions in the extended math library (see the **LIBRARY** section). This is a **non-portable extension**. **-e** *expr*, **-\-expression**=*expr* : Evaluates *expr*. If multiple expressions are given, they are evaluated in order. If files are given as well (see below), the expressions and files are evaluated in the order given. This means that if a file is given before an expression, the file is read in and evaluated first. If this option is given on the command-line (i.e., not in **BC_ENV_ARGS**, see the **ENVIRONMENT VARIABLES** section), then after processing all expressions and files, bc(1) will exit, unless **-** (**stdin**) was given as an argument at least once to **-f** or **-\-file**, whether on the command-line or in **BC_ENV_ARGS**. However, if any other **-e**, **-\-expression**, **-f**, or **-\-file** arguments are given after **-f-** or equivalent is given, bc(1) will give a fatal error and exit. This is a **non-portable extension**. **-f** *file*, **-\-file**=*file* : Reads in *file* and evaluates it, line by line, as though it were read through **stdin**. If expressions are also given (see above), the expressions are evaluated in the order given. If this option is given on the command-line (i.e., not in **BC_ENV_ARGS**, see the **ENVIRONMENT VARIABLES** section), then after processing all expressions and files, bc(1) will exit, unless **-** (**stdin**) was given as an argument at least once to **-f** or **-\-file**. However, if any other **-e**, **-\-expression**, **-f**, or **-\-file** arguments are given after **-f-** or equivalent is given, bc(1) will give a fatal error and exit. This is a **non-portable extension**. All long options are **non-portable extensions**. # STDIN If no files or expressions are given by the **-f**, **-\-file**, **-e**, or **-\-expression** options, then bc(1) read from **stdin**. However, there are a few caveats to this. First, **stdin** is evaluated a line at a time. The only exception to this is if the parse cannot complete. That means that starting a string without ending it or starting a function, **if** statement, or loop without ending it will also cause bc(1) to not execute. Second, after an **if** statement, bc(1) doesn't know if an **else** statement will follow, so it will not execute until it knows there will not be an **else** statement. # STDOUT Any non-error output is written to **stdout**. In addition, if history (see the **HISTORY** section) and the prompt (see the **TTY MODE** section) are enabled, both are output to **stdout**. **Note**: Unlike other bc(1) implementations, this bc(1) will issue a fatal error (see the **EXIT STATUS** section) if it cannot write to **stdout**, so if **stdout** is closed, as in **bc >&-**, it will quit with an error. This is done so that bc(1) can report problems when **stdout** is redirected to a file. If there are scripts that depend on the behavior of other bc(1) implementations, it is recommended that those scripts be changed to redirect **stdout** to **/dev/null**. # STDERR Any error output is written to **stderr**. **Note**: Unlike other bc(1) implementations, this bc(1) will issue a fatal error (see the **EXIT STATUS** section) if it cannot write to **stderr**, so if **stderr** is closed, as in **bc 2>&-**, it will quit with an error. This is done so that bc(1) can exit with an error code when **stderr** is redirected to a file. If there are scripts that depend on the behavior of other bc(1) implementations, it is recommended that those scripts be changed to redirect **stderr** to **/dev/null**. # SYNTAX The syntax for bc(1) programs is mostly C-like, with some differences. This bc(1) follows the [POSIX standard][1], which is a much more thorough resource for the language this bc(1) accepts. This section is meant to be a summary and a listing of all the extensions to the standard. In the sections below, **E** means expression, **S** means statement, and **I** means identifier. Identifiers (**I**) start with a lowercase letter and can be followed by any number (up to **BC_NAME_MAX-1**) of lowercase letters (**a-z**), digits (**0-9**), and underscores (**\_**). The regex is **\[a-z\]\[a-z0-9\_\]\***. Identifiers with more than one character (letter) are a **non-portable extension**. **ibase** is a global variable determining how to interpret constant numbers. It is the "input" base, or the number base used for interpreting input numbers. **ibase** is initially **10**. If the **-s** (**-\-standard**) and **-w** (**-\-warn**) flags were not given on the command line, the max allowable value for **ibase** is **36**. Otherwise, it is **16**. The min allowable value for **ibase** is **2**. The max allowable value for **ibase** can be queried in bc(1) programs with the **maxibase()** built-in function. **obase** is a global variable determining how to output results. It is the "output" base, or the number base used for outputting numbers. **obase** is initially **10**. The max allowable value for **obase** is **BC_BASE_MAX** and can be queried in bc(1) programs with the **maxobase()** built-in function. The min allowable value for **obase** is **0**. If **obase** is **0**, values are output in scientific notation, and if **obase** is **1**, values are output in engineering notation. Otherwise, values are output in the specified base. Outputting in scientific and engineering notations are **non-portable extensions**. The *scale* of an expression is the number of digits in the result of the expression right of the decimal point, and **scale** is a global variable that sets the precision of any operations, with exceptions. **scale** is initially **0**. **scale** cannot be negative. The max allowable value for **scale** is **BC_SCALE_MAX** and can be queried in bc(1) programs with the **maxscale()** built-in function. bc(1) has both *global* variables and *local* variables. All *local* variables are local to the function; they are parameters or are introduced in the **auto** list of a function (see the **FUNCTIONS** section). If a variable is accessed which is not a parameter or in the **auto** list, it is assumed to be *global*. If a parent function has a *local* variable version of a variable that a child function considers *global*, the value of that *global* variable in the child function is the value of the variable in the parent function, not the value of the actual *global* variable. All of the above applies to arrays as well. The value of a statement that is an expression (i.e., any of the named expressions or operands) is printed unless the lowest precedence operator is an assignment operator *and* the expression is notsurrounded by parentheses. The value that is printed is also assigned to the special variable **last**. A single dot (**.**) may also be used as a synonym for **last**. These are **non-portable extensions**. Either semicolons or newlines may separate statements. ## Comments There are two kinds of comments: 1. Block comments are enclosed in **/\*** and **\*/**. 2. Line comments go from **#** until, and not including, the next newline. This is a **non-portable extension**. ## Named Expressions The following are named expressions in bc(1): 1. Variables: **I** 2. Array Elements: **I[E]** 3. **ibase** 4. **obase** 5. **scale** 6. **seed** 7. **last** or a single dot (**.**) Numbers 6 and 7 are **non-portable extensions**. The meaning of **seed** is dependent on the current pseudo-random number generator but is guaranteed to not change except for new major versions. The *scale* and sign of the value may be significant. If a previously used **seed** value is assigned to **seed** and used again, the pseudo-random number generator is guaranteed to produce the same sequence of pseudo-random numbers as it did when the **seed** value was previously used. The exact value assigned to **seed** is not guaranteed to be returned if **seed** is queried again immediately. However, if **seed** *does* return a different value, both values, when assigned to **seed**, are guaranteed to produce the same sequence of pseudo-random numbers. This means that certain values assigned to **seed** will *not* produce unique sequences of pseudo-random numbers. The value of **seed** will change after any use of the **rand()** and **irand(E)** operands (see the *Operands* subsection below), except if the parameter passed to **irand(E)** is **0**, **1**, or negative. There is no limit to the length (number of significant decimal digits) or *scale* of the value that can be assigned to **seed**. Variables and arrays do not interfere; users can have arrays named the same as variables. This also applies to functions (see the **FUNCTIONS** section), so a user can have a variable, array, and function that all have the same name, and they will not shadow each other, whether inside of functions or not. Named expressions are required as the operand of **increment**/**decrement** operators and as the left side of **assignment** operators (see the *Operators* subsection). ## Operands The following are valid operands in bc(1): 1. Numbers (see the *Numbers* subsection below). 2. Array indices (**I[E]**). 3. **(E)**: The value of **E** (used to change precedence). 4. **sqrt(E)**: The square root of **E**. **E** must be non-negative. 5. **length(E)**: The number of significant decimal digits in **E**. Returns **1** for **0** with no decimal places. If given a string, the length of the string is returned. Passing a string to **length(E)** is a **non-portable extension**. 6. **length(I[])**: The number of elements in the array **I**. This is a **non-portable extension**. 7. **scale(E)**: The *scale* of **E**. 8. **abs(E)**: The absolute value of **E**. This is a **non-portable extension**. 9. **modexp(E, E, E)**: Modular exponentiation, where the first expression is the base, the second is the exponent, and the third is the modulus. All three values must be integers. The second argument must be non-negative. The third argument must be non-zero. This is a **non-portable extension**. 10. **divmod(E, E, I[])**: Division and modulus in one operation. This is for optimization. The first expression is the dividend, and the second is the divisor, which must be non-zero. The return value is the quotient, and the modulus is stored in index **0** of the provided array (the last argument). This is a **non-portable extension**. 11. **asciify(E)**: If **E** is a string, returns a string that is the first letter of its argument. If it is a number, calculates the number mod **256** and returns that number as a one-character string. This is a **non-portable extension**. 12. **I()**, **I(E)**, **I(E, E)**, and so on, where **I** is an identifier for a non-**void** function (see the *Void Functions* subsection of the **FUNCTIONS** section). The **E** argument(s) may also be arrays of the form **I[]**, which will automatically be turned into array references (see the *Array References* subsection of the **FUNCTIONS** section) if the corresponding parameter in the function definition is an array reference. 13. **read()**: Reads a line from **stdin** and uses that as an expression. The result of that expression is the result of the **read()** operand. This is a **non-portable extension**. 14. **maxibase()**: The max allowable **ibase**. This is a **non-portable extension**. 15. **maxobase()**: The max allowable **obase**. This is a **non-portable extension**. 16. **maxscale()**: The max allowable **scale**. This is a **non-portable extension**. 17. **line_length()**: The line length set with **BC_LINE_LENGTH** (see the **ENVIRONMENT VARIABLES** section). This is a **non-portable extension**. 18. **global_stacks()**: **0** if global stacks are not enabled with the **-g** or **-\-global-stacks** options, non-zero otherwise. See the **OPTIONS** section. This is a **non-portable extension**. 19. **leading_zero()**: **0** if leading zeroes are not enabled with the **-z** or **--leading-zeroes** options, non-zero otherwise. See the **OPTIONS** section. This is a **non-portable extension**. 20. **rand()**: A pseudo-random integer between **0** (inclusive) and **BC_RAND_MAX** (inclusive). Using this operand will change the value of **seed**. This is a **non-portable extension**. 21. **irand(E)**: A pseudo-random integer between **0** (inclusive) and the value of **E** (exclusive). If **E** is negative or is a non-integer (**E**'s *scale* is not **0**), an error is raised, and bc(1) resets (see the **RESET** section) while **seed** remains unchanged. If **E** is larger than **BC_RAND_MAX**, the higher bound is honored by generating several pseudo-random integers, multiplying them by appropriate powers of **BC_RAND_MAX+1**, and adding them together. Thus, the size of integer that can be generated with this operand is unbounded. Using this operand will change the value of **seed**, unless the value of **E** is **0** or **1**. In that case, **0** is returned, and **seed** is *not* changed. This is a **non-portable extension**. 22. **maxrand()**: The max integer returned by **rand()**. This is a **non-portable extension**. The integers generated by **rand()** and **irand(E)** are guaranteed to be as unbiased as possible, subject to the limitations of the pseudo-random number generator. **Note**: The values returned by the pseudo-random number generator with **rand()** and **irand(E)** are guaranteed to *NOT* be cryptographically secure. This is a consequence of using a seeded pseudo-random number generator. However, they *are* guaranteed to be reproducible with identical **seed** values. This means that the pseudo-random values from bc(1) should only be used where a reproducible stream of pseudo-random numbers is *ESSENTIAL*. In any other case, use a non-seeded pseudo-random number generator. ## Numbers Numbers are strings made up of digits, uppercase letters, and at most **1** period for a radix. Numbers can have up to **BC_NUM_MAX** digits. Uppercase letters are equal to **9** + their position in the alphabet (i.e., **A** equals **10**, or **9+1**). If a digit or letter makes no sense with the current value of **ibase**, they are set to the value of the highest valid digit in **ibase**. Single-character numbers (i.e., **A** alone) take the value that they would have if they were valid digits, regardless of the value of **ibase**. This means that **A** alone always equals decimal **10** and **Z** alone always equals decimal **35**. In addition, bc(1) accepts numbers in scientific notation. These have the form **\e\**. The exponent (the portion after the **e**) must be an integer. An example is **1.89237e9**, which is equal to **1892370000**. Negative exponents are also allowed, so **4.2890e-3** is equal to **0.0042890**. Using scientific notation is an error or warning if the **-s** or **-w**, respectively, command-line options (or equivalents) are given. **WARNING**: Both the number and the exponent in scientific notation are interpreted according to the current **ibase**, but the number is still multiplied by **10\^exponent** regardless of the current **ibase**. For example, if **ibase** is **16** and bc(1) is given the number string **FFeA**, the resulting decimal number will be **2550000000000**, and if bc(1) is given the number string **10e-4**, the resulting decimal number will be **0.0016**. Accepting input as scientific notation is a **non-portable extension**. ## Operators The following arithmetic and logical operators can be used. They are listed in order of decreasing precedence. Operators in the same group have the same precedence. **++** **-\-** : Type: Prefix and Postfix Associativity: None Description: **increment**, **decrement** **-** **!** : Type: Prefix Associativity: None Description: **negation**, **boolean not** **\$** : Type: Postfix Associativity: None Description: **truncation** **\@** : Type: Binary Associativity: Right Description: **set precision** **\^** : Type: Binary Associativity: Right Description: **power** **\*** **/** **%** : Type: Binary Associativity: Left Description: **multiply**, **divide**, **modulus** **+** **-** : Type: Binary Associativity: Left Description: **add**, **subtract** **\<\<** **\>\>** : Type: Binary Associativity: Left Description: **shift left**, **shift right** **=** **\<\<=** **\>\>=** **+=** **-=** **\*=** **/=** **%=** **\^=** **\@=** : Type: Binary Associativity: Right Description: **assignment** **==** **\<=** **\>=** **!=** **\<** **\>** : Type: Binary Associativity: Left Description: **relational** **&&** : Type: Binary Associativity: Left Description: **boolean and** **||** : Type: Binary Associativity: Left Description: **boolean or** The operators will be described in more detail below. **++** **-\-** : The prefix and postfix **increment** and **decrement** operators behave exactly like they would in C. They require a named expression (see the *Named Expressions* subsection) as an operand. The prefix versions of these operators are more efficient; use them where possible. **-** : The **negation** operator returns **0** if a user attempts to negate any expression with the value **0**. Otherwise, a copy of the expression with its sign flipped is returned. **!** : The **boolean not** operator returns **1** if the expression is **0**, or **0** otherwise. This is a **non-portable extension**. **\$** : The **truncation** operator returns a copy of the given expression with all of its *scale* removed. This is a **non-portable extension**. **\@** : The **set precision** operator takes two expressions and returns a copy of the first with its *scale* equal to the value of the second expression. That could either mean that the number is returned without change (if the *scale* of the first expression matches the value of the second expression), extended (if it is less), or truncated (if it is more). The second expression must be an integer (no *scale*) and non-negative. This is a **non-portable extension**. **\^** : The **power** operator (not the **exclusive or** operator, as it would be in C) takes two expressions and raises the first to the power of the value of the second. The *scale* of the result is equal to **scale**. The second expression must be an integer (no *scale*), and if it is negative, the first value must be non-zero. **\*** : The **multiply** operator takes two expressions, multiplies them, and returns the product. If **a** is the *scale* of the first expression and **b** is the *scale* of the second expression, the *scale* of the result is equal to **min(a+b,max(scale,a,b))** where **min()** and **max()** return the obvious values. **/** : The **divide** operator takes two expressions, divides them, and returns the quotient. The *scale* of the result shall be the value of **scale**. The second expression must be non-zero. **%** : The **modulus** operator takes two expressions, **a** and **b**, and evaluates them by 1) Computing **a/b** to current **scale** and 2) Using the result of step 1 to calculate **a-(a/b)\*b** to *scale* **max(scale+scale(b),scale(a))**. The second expression must be non-zero. **+** : The **add** operator takes two expressions, **a** and **b**, and returns the sum, with a *scale* equal to the max of the *scale*s of **a** and **b**. **-** : The **subtract** operator takes two expressions, **a** and **b**, and returns the difference, with a *scale* equal to the max of the *scale*s of **a** and **b**. **\<\<** : The **left shift** operator takes two expressions, **a** and **b**, and returns a copy of the value of **a** with its decimal point moved **b** places to the right. The second expression must be an integer (no *scale*) and non-negative. This is a **non-portable extension**. **\>\>** : The **right shift** operator takes two expressions, **a** and **b**, and returns a copy of the value of **a** with its decimal point moved **b** places to the left. The second expression must be an integer (no *scale*) and non-negative. This is a **non-portable extension**. **=** **\<\<=** **\>\>=** **+=** **-=** **\*=** **/=** **%=** **\^=** **\@=** : The **assignment** operators take two expressions, **a** and **b** where **a** is a named expression (see the *Named Expressions* subsection). For **=**, **b** is copied and the result is assigned to **a**. For all others, **a** and **b** are applied as operands to the corresponding arithmetic operator and the result is assigned to **a**. The **assignment** operators that correspond to operators that are extensions are themselves **non-portable extensions**. **==** **\<=** **\>=** **!=** **\<** **\>** : The **relational** operators compare two expressions, **a** and **b**, and if the relation holds, according to C language semantics, the result is **1**. Otherwise, it is **0**. Note that unlike in C, these operators have a lower precedence than the **assignment** operators, which means that **a=b\>c** is interpreted as **(a=b)\>c**. Also, unlike the [standard][1] requires, these operators can appear anywhere any other expressions can be used. This allowance is a **non-portable extension**. **&&** : The **boolean and** operator takes two expressions and returns **1** if both expressions are non-zero, **0** otherwise. This is *not* a short-circuit operator. This is a **non-portable extension**. **||** : The **boolean or** operator takes two expressions and returns **1** if one of the expressions is non-zero, **0** otherwise. This is *not* a short-circuit operator. This is a **non-portable extension**. ## Statements The following items are statements: 1. **E** 2. **{** **S** **;** ... **;** **S** **}** 3. **if** **(** **E** **)** **S** 4. **if** **(** **E** **)** **S** **else** **S** 5. **while** **(** **E** **)** **S** 6. **for** **(** **E** **;** **E** **;** **E** **)** **S** 7. An empty statement 8. **break** 9. **continue** 10. **quit** 11. **halt** 12. **limits** 13. A string of characters, enclosed in double quotes 14. **print** **E** **,** ... **,** **E** 15. **stream** **E** **,** ... **,** **E** 16. **I()**, **I(E)**, **I(E, E)**, and so on, where **I** is an identifier for a **void** function (see the *Void Functions* subsection of the **FUNCTIONS** section). The **E** argument(s) may also be arrays of the form **I[]**, which will automatically be turned into array references (see the *Array References* subsection of the **FUNCTIONS** section) if the corresponding parameter in the function definition is an array reference. Numbers 4, 9, 11, 12, 14, 15, and 16 are **non-portable extensions**. Also, as a **non-portable extension**, any or all of the expressions in the header of a for loop may be omitted. If the condition (second expression) is omitted, it is assumed to be a constant **1**. The **break** statement causes a loop to stop iterating and resume execution immediately following a loop. This is only allowed in loops. The **continue** statement causes a loop iteration to stop early and returns to the start of the loop, including testing the loop condition. This is only allowed in loops. The **if** **else** statement does the same thing as in C. The **quit** statement causes bc(1) to quit, even if it is on a branch that will not be executed (it is a compile-time command). The **halt** statement causes bc(1) to quit, if it is executed. (Unlike **quit** if it is on a branch of an **if** statement that is not executed, bc(1) does not quit.) The **limits** statement prints the limits that this bc(1) is subject to. This is like the **quit** statement in that it is a compile-time command. An expression by itself is evaluated and printed, followed by a newline. Both scientific notation and engineering notation are available for printing the results of expressions. Scientific notation is activated by assigning **0** to **obase**, and engineering notation is activated by assigning **1** to **obase**. To deactivate them, just assign a different value to **obase**. Scientific notation and engineering notation are disabled if bc(1) is run with either the **-s** or **-w** command-line options (or equivalents). Printing numbers in scientific notation and/or engineering notation is a **non-portable extension**. ## Strings If strings appear as a statement by themselves, they are printed without a trailing newline. In addition to appearing as a lone statement by themselves, strings can be assigned to variables and array elements. They can also be passed to functions in variable parameters. If any statement that expects a string is given a variable that had a string assigned to it, the statement acts as though it had received a string. If any math operation is attempted on a string or a variable or array element that has been assigned a string, an error is raised, and bc(1) resets (see the **RESET** section). Assigning strings to variables and array elements and passing them to functions are **non-portable extensions**. ## Print Statement The "expressions" in a **print** statement may also be strings. If they are, there are backslash escape sequences that are interpreted specially. What those sequences are, and what they cause to be printed, are shown below: **\\a**: **\\a** **\\b**: **\\b** **\\\\**: **\\** **\\e**: **\\** **\\f**: **\\f** **\\n**: **\\n** **\\q**: **"** **\\r**: **\\r** **\\t**: **\\t** Any other character following a backslash causes the backslash and character to be printed as-is. Any non-string expression in a print statement shall be assigned to **last**, like any other expression that is printed. ## Stream Statement The "expressions in a **stream** statement may also be strings. If a **stream** statement is given a string, it prints the string as though the string had appeared as its own statement. In other words, the **stream** statement prints strings normally, without a newline. If a **stream** statement is given a number, a copy of it is truncated and its absolute value is calculated. The result is then printed as though **obase** is **256** and each digit is interpreted as an 8-bit ASCII character, making it a byte stream. ## Order of Evaluation All expressions in a statment are evaluated left to right, except as necessary to maintain order of operations. This means, for example, assuming that **i** is equal to **0**, in the expression a[i++] = i++ the first (or 0th) element of **a** is set to **1**, and **i** is equal to **2** at the end of the expression. This includes function arguments. Thus, assuming **i** is equal to **0**, this means that in the expression x(i++, i++) the first argument passed to **x()** is **0**, and the second argument is **1**, while **i** is equal to **2** before the function starts executing. # FUNCTIONS Function definitions are as follows: ``` define I(I,...,I){ auto I,...,I S;...;S return(E) } ``` Any **I** in the parameter list or **auto** list may be replaced with **I[]** to make a parameter or **auto** var an array, and any **I** in the parameter list may be replaced with **\*I[]** to make a parameter an array reference. Callers of functions that take array references should not put an asterisk in the call; they must be called with just **I[]** like normal array parameters and will be automatically converted into references. As a **non-portable extension**, the opening brace of a **define** statement may appear on the next line. As a **non-portable extension**, the return statement may also be in one of the following forms: 1. **return** 2. **return** **(** **)** 3. **return** **E** The first two, or not specifying a **return** statement, is equivalent to **return (0)**, unless the function is a **void** function (see the *Void Functions* subsection below). ## Void Functions Functions can also be **void** functions, defined as follows: ``` define void I(I,...,I){ auto I,...,I S;...;S return } ``` They can only be used as standalone expressions, where such an expression would be printed alone, except in a print statement. Void functions can only use the first two **return** statements listed above. They can also omit the return statement entirely. The word "void" is not treated as a keyword; it is still possible to have variables, arrays, and functions named **void**. The word "void" is only treated specially right after the **define** keyword. This is a **non-portable extension**. ## Array References For any array in the parameter list, if the array is declared in the form ``` *I[] ``` it is a **reference**. Any changes to the array in the function are reflected, when the function returns, to the array that was passed in. Other than this, all function arguments are passed by value. This is a **non-portable extension**. # LIBRARY All of the functions below, including the functions in the extended math library (see the *Extended Library* subsection below), are available when the **-l** or **-\-mathlib** command-line flags are given, except that the extended math library is not available when the **-s** option, the **-w** option, or equivalents are given. ## Standard Library The [standard][1] defines the following functions for the math library: **s(x)** : Returns the sine of **x**, which is assumed to be in radians. This is a transcendental function (see the *Transcendental Functions* subsection below). **c(x)** : Returns the cosine of **x**, which is assumed to be in radians. This is a transcendental function (see the *Transcendental Functions* subsection below). **a(x)** : Returns the arctangent of **x**, in radians. This is a transcendental function (see the *Transcendental Functions* subsection below). **l(x)** : Returns the natural logarithm of **x**. This is a transcendental function (see the *Transcendental Functions* subsection below). **e(x)** : Returns the mathematical constant **e** raised to the power of **x**. This is a transcendental function (see the *Transcendental Functions* subsection below). **j(x, n)** : Returns the bessel integer order **n** (truncated) of **x**. This is a transcendental function (see the *Transcendental Functions* subsection below). ## Extended Library The extended library is *not* loaded when the **-s**/**-\-standard** or **-w**/**-\-warn** options are given since they are not part of the library defined by the [standard][1]. The extended library is a **non-portable extension**. **p(x, y)** : Calculates **x** to the power of **y**, even if **y** is not an integer, and returns the result to the current **scale**. It is an error if **y** is negative and **x** is **0**. This is a transcendental function (see the *Transcendental Functions* subsection below). **r(x, p)** : Returns **x** rounded to **p** decimal places according to the rounding mode [round half away from **0**][3]. **ceil(x, p)** : Returns **x** rounded to **p** decimal places according to the rounding mode [round away from **0**][6]. **f(x)** : Returns the factorial of the truncated absolute value of **x**. **perm(n, k)** : Returns the permutation of the truncated absolute value of **n** of the truncated absolute value of **k**, if **k \<= n**. If not, it returns **0**. **comb(n, k)** : Returns the combination of the truncated absolute value of **n** of the truncated absolute value of **k**, if **k \<= n**. If not, it returns **0**. **l2(x)** : Returns the logarithm base **2** of **x**. This is a transcendental function (see the *Transcendental Functions* subsection below). **l10(x)** : Returns the logarithm base **10** of **x**. This is a transcendental function (see the *Transcendental Functions* subsection below). **log(x, b)** : Returns the logarithm base **b** of **x**. This is a transcendental function (see the *Transcendental Functions* subsection below). **cbrt(x)** : Returns the cube root of **x**. **root(x, n)** : Calculates the truncated value of **n**, **r**, and returns the **r**th root of **x** to the current **scale**. If **r** is **0** or negative, this raises an error and causes bc(1) to reset (see the **RESET** section). It also raises an error and causes bc(1) to reset if **r** is even and **x** is negative. **gcd(a, b)** : Returns the greatest common divisor (factor) of the truncated absolute value of **a** and the truncated absolute value of **b**. **lcm(a, b)** : Returns the least common multiple of the truncated absolute value of **a** and the truncated absolute value of **b**. **pi(p)** : Returns **pi** to **p** decimal places. This is a transcendental function (see the *Transcendental Functions* subsection below). **t(x)** : Returns the tangent of **x**, which is assumed to be in radians. This is a transcendental function (see the *Transcendental Functions* subsection below). **a2(y, x)** : Returns the arctangent of **y/x**, in radians. If both **y** and **x** are equal to **0**, it raises an error and causes bc(1) to reset (see the **RESET** section). Otherwise, if **x** is greater than **0**, it returns **a(y/x)**. If **x** is less than **0**, and **y** is greater than or equal to **0**, it returns **a(y/x)+pi**. If **x** is less than **0**, and **y** is less than **0**, it returns **a(y/x)-pi**. If **x** is equal to **0**, and **y** is greater than **0**, it returns **pi/2**. If **x** is equal to **0**, and **y** is less than **0**, it returns **-pi/2**. This function is the same as the **atan2()** function in many programming languages. This is a transcendental function (see the *Transcendental Functions* subsection below). **sin(x)** : Returns the sine of **x**, which is assumed to be in radians. This is an alias of **s(x)**. This is a transcendental function (see the *Transcendental Functions* subsection below). **cos(x)** : Returns the cosine of **x**, which is assumed to be in radians. This is an alias of **c(x)**. This is a transcendental function (see the *Transcendental Functions* subsection below). **tan(x)** : Returns the tangent of **x**, which is assumed to be in radians. If **x** is equal to **1** or **-1**, this raises an error and causes bc(1) to reset (see the **RESET** section). This is an alias of **t(x)**. This is a transcendental function (see the *Transcendental Functions* subsection below). **atan(x)** : Returns the arctangent of **x**, in radians. This is an alias of **a(x)**. This is a transcendental function (see the *Transcendental Functions* subsection below). **atan2(y, x)** : Returns the arctangent of **y/x**, in radians. If both **y** and **x** are equal to **0**, it raises an error and causes bc(1) to reset (see the **RESET** section). Otherwise, if **x** is greater than **0**, it returns **a(y/x)**. If **x** is less than **0**, and **y** is greater than or equal to **0**, it returns **a(y/x)+pi**. If **x** is less than **0**, and **y** is less than **0**, it returns **a(y/x)-pi**. If **x** is equal to **0**, and **y** is greater than **0**, it returns **pi/2**. If **x** is equal to **0**, and **y** is less than **0**, it returns **-pi/2**. This function is the same as the **atan2()** function in many programming languages. This is an alias of **a2(y, x)**. This is a transcendental function (see the *Transcendental Functions* subsection below). **r2d(x)** : Converts **x** from radians to degrees and returns the result. This is a transcendental function (see the *Transcendental Functions* subsection below). **d2r(x)** : Converts **x** from degrees to radians and returns the result. This is a transcendental function (see the *Transcendental Functions* subsection below). **frand(p)** : Generates a pseudo-random number between **0** (inclusive) and **1** (exclusive) with the number of decimal digits after the decimal point equal to the truncated absolute value of **p**. If **p** is not **0**, then calling this function will change the value of **seed**. If **p** is **0**, then **0** is returned, and **seed** is *not* changed. **ifrand(i, p)** : Generates a pseudo-random number that is between **0** (inclusive) and the truncated absolute value of **i** (exclusive) with the number of decimal digits after the decimal point equal to the truncated absolute value of **p**. If the absolute value of **i** is greater than or equal to **2**, and **p** is not **0**, then calling this function will change the value of **seed**; otherwise, **0** is returned and **seed** is not changed. **srand(x)** : Returns **x** with its sign flipped with probability **0.5**. In other words, it randomizes the sign of **x**. **brand()** : Returns a random boolean value (either **0** or **1**). **band(a, b)** : Takes the truncated absolute value of both **a** and **b** and calculates and returns the result of the bitwise **and** operation between them. If you want to use signed two's complement arguments, use **s2u(x)** to convert. **bor(a, b)** : Takes the truncated absolute value of both **a** and **b** and calculates and returns the result of the bitwise **or** operation between them. If you want to use signed two's complement arguments, use **s2u(x)** to convert. **bxor(a, b)** : Takes the truncated absolute value of both **a** and **b** and calculates and returns the result of the bitwise **xor** operation between them. If you want to use signed two's complement arguments, use **s2u(x)** to convert. **bshl(a, b)** : Takes the truncated absolute value of both **a** and **b** and calculates and returns the result of **a** bit-shifted left by **b** places. If you want to use signed two's complement arguments, use **s2u(x)** to convert. **bshr(a, b)** : Takes the truncated absolute value of both **a** and **b** and calculates and returns the truncated result of **a** bit-shifted right by **b** places. If you want to use signed two's complement arguments, use **s2u(x)** to convert. **bnotn(x, n)** : Takes the truncated absolute value of **x** and does a bitwise not as though it has the same number of bytes as the truncated absolute value of **n**. If you want to a use signed two's complement argument, use **s2u(x)** to convert. **bnot8(x)** : Does a bitwise not of the truncated absolute value of **x** as though it has **8** binary digits (1 unsigned byte). If you want to a use signed two's complement argument, use **s2u(x)** to convert. **bnot16(x)** : Does a bitwise not of the truncated absolute value of **x** as though it has **16** binary digits (2 unsigned bytes). If you want to a use signed two's complement argument, use **s2u(x)** to convert. **bnot32(x)** : Does a bitwise not of the truncated absolute value of **x** as though it has **32** binary digits (4 unsigned bytes). If you want to a use signed two's complement argument, use **s2u(x)** to convert. **bnot64(x)** : Does a bitwise not of the truncated absolute value of **x** as though it has **64** binary digits (8 unsigned bytes). If you want to a use signed two's complement argument, use **s2u(x)** to convert. **bnot(x)** : Does a bitwise not of the truncated absolute value of **x** as though it has the minimum number of power of two unsigned bytes. If you want to a use signed two's complement argument, use **s2u(x)** to convert. **brevn(x, n)** : Runs a bit reversal on the truncated absolute value of **x** as though it has the same number of 8-bit bytes as the truncated absolute value of **n**. If you want to a use signed two's complement argument, use **s2u(x)** to convert. **brev8(x)** : Runs a bit reversal on the truncated absolute value of **x** as though it has 8 binary digits (1 unsigned byte). If you want to a use signed two's complement argument, use **s2u(x)** to convert. **brev16(x)** : Runs a bit reversal on the truncated absolute value of **x** as though it has 16 binary digits (2 unsigned bytes). If you want to a use signed two's complement argument, use **s2u(x)** to convert. **brev32(x)** : Runs a bit reversal on the truncated absolute value of **x** as though it has 32 binary digits (4 unsigned bytes). If you want to a use signed two's complement argument, use **s2u(x)** to convert. **brev64(x)** : Runs a bit reversal on the truncated absolute value of **x** as though it has 64 binary digits (8 unsigned bytes). If you want to a use signed two's complement argument, use **s2u(x)** to convert. **brev(x)** : Runs a bit reversal on the truncated absolute value of **x** as though it has the minimum number of power of two unsigned bytes. If you want to a use signed two's complement argument, use **s2u(x)** to convert. **broln(x, p, n)** : Does a left bitwise rotatation of the truncated absolute value of **x**, as though it has the same number of unsigned 8-bit bytes as the truncated absolute value of **n**, by the number of places equal to the truncated absolute value of **p** modded by the **2** to the power of the number of binary digits in **n** 8-bit bytes. If you want to a use signed two's complement argument, use **s2u(x)** to convert. **brol8(x, p)** : Does a left bitwise rotatation of the truncated absolute value of **x**, as though it has **8** binary digits (**1** unsigned byte), by the number of places equal to the truncated absolute value of **p** modded by **2** to the power of **8**. If you want to a use signed two's complement argument, use **s2u(x)** to convert. **brol16(x, p)** : Does a left bitwise rotatation of the truncated absolute value of **x**, as though it has **16** binary digits (**2** unsigned bytes), by the number of places equal to the truncated absolute value of **p** modded by **2** to the power of **16**. If you want to a use signed two's complement argument, use **s2u(x)** to convert. **brol32(x, p)** : Does a left bitwise rotatation of the truncated absolute value of **x**, as though it has **32** binary digits (**2** unsigned bytes), by the number of places equal to the truncated absolute value of **p** modded by **2** to the power of **32**. If you want to a use signed two's complement argument, use **s2u(x)** to convert. **brol64(x, p)** : Does a left bitwise rotatation of the truncated absolute value of **x**, as though it has **64** binary digits (**2** unsigned bytes), by the number of places equal to the truncated absolute value of **p** modded by **2** to the power of **64**. If you want to a use signed two's complement argument, use **s2u(x)** to convert. **brol(x, p)** : Does a left bitwise rotatation of the truncated absolute value of **x**, as though it has the minimum number of power of two unsigned 8-bit bytes, by the number of places equal to the truncated absolute value of **p** modded by 2 to the power of the number of binary digits in the minimum number of 8-bit bytes. If you want to a use signed two's complement argument, use **s2u(x)** to convert. **brorn(x, p, n)** : Does a right bitwise rotatation of the truncated absolute value of **x**, as though it has the same number of unsigned 8-bit bytes as the truncated absolute value of **n**, by the number of places equal to the truncated absolute value of **p** modded by the **2** to the power of the number of binary digits in **n** 8-bit bytes. If you want to a use signed two's complement argument, use **s2u(x)** to convert. **bror8(x, p)** : Does a right bitwise rotatation of the truncated absolute value of **x**, as though it has **8** binary digits (**1** unsigned byte), by the number of places equal to the truncated absolute value of **p** modded by **2** to the power of **8**. If you want to a use signed two's complement argument, use **s2u(x)** to convert. **bror16(x, p)** : Does a right bitwise rotatation of the truncated absolute value of **x**, as though it has **16** binary digits (**2** unsigned bytes), by the number of places equal to the truncated absolute value of **p** modded by **2** to the power of **16**. If you want to a use signed two's complement argument, use **s2u(x)** to convert. **bror32(x, p)** : Does a right bitwise rotatation of the truncated absolute value of **x**, as though it has **32** binary digits (**2** unsigned bytes), by the number of places equal to the truncated absolute value of **p** modded by **2** to the power of **32**. If you want to a use signed two's complement argument, use **s2u(x)** to convert. **bror64(x, p)** : Does a right bitwise rotatation of the truncated absolute value of **x**, as though it has **64** binary digits (**2** unsigned bytes), by the number of places equal to the truncated absolute value of **p** modded by **2** to the power of **64**. If you want to a use signed two's complement argument, use **s2u(x)** to convert. **bror(x, p)** : Does a right bitwise rotatation of the truncated absolute value of **x**, as though it has the minimum number of power of two unsigned 8-bit bytes, by the number of places equal to the truncated absolute value of **p** modded by 2 to the power of the number of binary digits in the minimum number of 8-bit bytes. If you want to a use signed two's complement argument, use **s2u(x)** to convert. **bmodn(x, n)** : Returns the modulus of the truncated absolute value of **x** by **2** to the power of the multiplication of the truncated absolute value of **n** and **8**. If you want to a use signed two's complement argument, use **s2u(x)** to convert. **bmod8(x, n)** : Returns the modulus of the truncated absolute value of **x** by **2** to the power of **8**. If you want to a use signed two's complement argument, use **s2u(x)** to convert. **bmod16(x, n)** : Returns the modulus of the truncated absolute value of **x** by **2** to the power of **16**. If you want to a use signed two's complement argument, use **s2u(x)** to convert. **bmod32(x, n)** : Returns the modulus of the truncated absolute value of **x** by **2** to the power of **32**. If you want to a use signed two's complement argument, use **s2u(x)** to convert. **bmod64(x, n)** : Returns the modulus of the truncated absolute value of **x** by **2** to the power of **64**. If you want to a use signed two's complement argument, use **s2u(x)** to convert. **bunrev(t)** : Assumes **t** is a bitwise-reversed number with an extra set bit one place more significant than the real most significant bit (which was the least significant bit in the original number). This number is reversed and returned without the extra set bit. This function is used to implement other bitwise functions; it is not meant to be used by users, but it can be. **plz(x)** : If **x** is not equal to **0** and greater that **-1** and less than **1**, it is printed with a leading zero, regardless of the use of the **-z** option (see the **OPTIONS** section) and without a trailing newline. Otherwise, **x** is printed normally, without a trailing newline. **plznl(x)** : If **x** is not equal to **0** and greater that **-1** and less than **1**, it is printed with a leading zero, regardless of the use of the **-z** option (see the **OPTIONS** section) and with a trailing newline. Otherwise, **x** is printed normally, with a trailing newline. **pnlz(x)** : If **x** is not equal to **0** and greater that **-1** and less than **1**, it is printed without a leading zero, regardless of the use of the **-z** option (see the **OPTIONS** section) and without a trailing newline. Otherwise, **x** is printed normally, without a trailing newline. **pnlznl(x)** : If **x** is not equal to **0** and greater that **-1** and less than **1**, it is printed without a leading zero, regardless of the use of the **-z** option (see the **OPTIONS** section) and with a trailing newline. Otherwise, **x** is printed normally, with a trailing newline. **ubytes(x)** : Returns the numbers of unsigned integer bytes required to hold the truncated absolute value of **x**. **sbytes(x)** : Returns the numbers of signed, two's-complement integer bytes required to hold the truncated value of **x**. **s2u(x)** : Returns **x** if it is non-negative. If it *is* negative, then it calculates what **x** would be as a 2's-complement signed integer and returns the non-negative integer that would have the same representation in binary. **s2un(x,n)** : Returns **x** if it is non-negative. If it *is* negative, then it calculates what **x** would be as a 2's-complement signed integer with **n** bytes and returns the non-negative integer that would have the same representation in binary. If **x** cannot fit into **n** 2's-complement signed bytes, it is truncated to fit. **hex(x)** : Outputs the hexadecimal (base **16**) representation of **x**. This is a **void** function (see the *Void Functions* subsection of the **FUNCTIONS** section). **binary(x)** : Outputs the binary (base **2**) representation of **x**. This is a **void** function (see the *Void Functions* subsection of the **FUNCTIONS** section). **output(x, b)** : Outputs the base **b** representation of **x**. This is a **void** function (see the *Void Functions* subsection of the **FUNCTIONS** section). **uint(x)** : Outputs the representation, in binary and hexadecimal, of **x** as an unsigned integer in as few power of two bytes as possible. Both outputs are split into bytes separated by spaces. If **x** is not an integer or is negative, an error message is printed instead, but bc(1) is not reset (see the **RESET** section). This is a **void** function (see the *Void Functions* subsection of the **FUNCTIONS** section). **int(x)** : Outputs the representation, in binary and hexadecimal, of **x** as a signed, two's-complement integer in as few power of two bytes as possible. Both outputs are split into bytes separated by spaces. If **x** is not an integer, an error message is printed instead, but bc(1) is not reset (see the **RESET** section). This is a **void** function (see the *Void Functions* subsection of the **FUNCTIONS** section). **uintn(x, n)** : Outputs the representation, in binary and hexadecimal, of **x** as an unsigned integer in **n** bytes. Both outputs are split into bytes separated by spaces. If **x** is not an integer, is negative, or cannot fit into **n** bytes, an error message is printed instead, but bc(1) is not reset (see the **RESET** section). This is a **void** function (see the *Void Functions* subsection of the **FUNCTIONS** section). **intn(x, n)** : Outputs the representation, in binary and hexadecimal, of **x** as a signed, two's-complement integer in **n** bytes. Both outputs are split into bytes separated by spaces. If **x** is not an integer or cannot fit into **n** bytes, an error message is printed instead, but bc(1) is not reset (see the **RESET** section). This is a **void** function (see the *Void Functions* subsection of the **FUNCTIONS** section). **uint8(x)** : Outputs the representation, in binary and hexadecimal, of **x** as an unsigned integer in **1** byte. Both outputs are split into bytes separated by spaces. If **x** is not an integer, is negative, or cannot fit into **1** byte, an error message is printed instead, but bc(1) is not reset (see the **RESET** section). This is a **void** function (see the *Void Functions* subsection of the **FUNCTIONS** section). **int8(x)** : Outputs the representation, in binary and hexadecimal, of **x** as a signed, two's-complement integer in **1** byte. Both outputs are split into bytes separated by spaces. If **x** is not an integer or cannot fit into **1** byte, an error message is printed instead, but bc(1) is not reset (see the **RESET** section). This is a **void** function (see the *Void Functions* subsection of the **FUNCTIONS** section). **uint16(x)** : Outputs the representation, in binary and hexadecimal, of **x** as an unsigned integer in **2** bytes. Both outputs are split into bytes separated by spaces. If **x** is not an integer, is negative, or cannot fit into **2** bytes, an error message is printed instead, but bc(1) is not reset (see the **RESET** section). This is a **void** function (see the *Void Functions* subsection of the **FUNCTIONS** section). **int16(x)** : Outputs the representation, in binary and hexadecimal, of **x** as a signed, two's-complement integer in **2** bytes. Both outputs are split into bytes separated by spaces. If **x** is not an integer or cannot fit into **2** bytes, an error message is printed instead, but bc(1) is not reset (see the **RESET** section). This is a **void** function (see the *Void Functions* subsection of the **FUNCTIONS** section). **uint32(x)** : Outputs the representation, in binary and hexadecimal, of **x** as an unsigned integer in **4** bytes. Both outputs are split into bytes separated by spaces. If **x** is not an integer, is negative, or cannot fit into **4** bytes, an error message is printed instead, but bc(1) is not reset (see the **RESET** section). This is a **void** function (see the *Void Functions* subsection of the **FUNCTIONS** section). **int32(x)** : Outputs the representation, in binary and hexadecimal, of **x** as a signed, two's-complement integer in **4** bytes. Both outputs are split into bytes separated by spaces. If **x** is not an integer or cannot fit into **4** bytes, an error message is printed instead, but bc(1) is not reset (see the **RESET** section). This is a **void** function (see the *Void Functions* subsection of the **FUNCTIONS** section). **uint64(x)** : Outputs the representation, in binary and hexadecimal, of **x** as an unsigned integer in **8** bytes. Both outputs are split into bytes separated by spaces. If **x** is not an integer, is negative, or cannot fit into **8** bytes, an error message is printed instead, but bc(1) is not reset (see the **RESET** section). This is a **void** function (see the *Void Functions* subsection of the **FUNCTIONS** section). **int64(x)** : Outputs the representation, in binary and hexadecimal, of **x** as a signed, two's-complement integer in **8** bytes. Both outputs are split into bytes separated by spaces. If **x** is not an integer or cannot fit into **8** bytes, an error message is printed instead, but bc(1) is not reset (see the **RESET** section). This is a **void** function (see the *Void Functions* subsection of the **FUNCTIONS** section). **hex_uint(x, n)** : Outputs the representation of the truncated absolute value of **x** as an unsigned integer in hexadecimal using **n** bytes. Not all of the value will be output if **n** is too small. This is a **void** function (see the *Void Functions* subsection of the **FUNCTIONS** section). **binary_uint(x, n)** : Outputs the representation of the truncated absolute value of **x** as an unsigned integer in binary using **n** bytes. Not all of the value will be output if **n** is too small. This is a **void** function (see the *Void Functions* subsection of the **FUNCTIONS** section). **output_uint(x, n)** : Outputs the representation of the truncated absolute value of **x** as an unsigned integer in the current **obase** (see the **SYNTAX** section) using **n** bytes. Not all of the value will be output if **n** is too small. This is a **void** function (see the *Void Functions* subsection of the **FUNCTIONS** section). **output_byte(x, i)** : Outputs byte **i** of the truncated absolute value of **x**, where **0** is the least significant byte and **number_of_bytes - 1** is the most significant byte. This is a **void** function (see the *Void Functions* subsection of the **FUNCTIONS** section). ## Transcendental Functions All transcendental functions can return slightly inaccurate results (up to 1 [ULP][4]). This is unavoidable, and [this article][5] explains why it is impossible and unnecessary to calculate exact results for the transcendental functions. Because of the possible inaccuracy, I recommend that users call those functions with the precision (**scale**) set to at least 1 higher than is necessary. If exact results are *absolutely* required, users can double the precision (**scale**) and then truncate. The transcendental functions in the standard math library are: * **s(x)** * **c(x)** * **a(x)** * **l(x)** * **e(x)** * **j(x, n)** The transcendental functions in the extended math library are: * **l2(x)** * **l10(x)** * **log(x, b)** * **pi(p)** * **t(x)** * **a2(y, x)** * **sin(x)** * **cos(x)** * **tan(x)** * **atan(x)** * **atan2(y, x)** * **r2d(x)** * **d2r(x)** # RESET When bc(1) encounters an error or a signal that it has a non-default handler for, it resets. This means that several things happen. First, any functions that are executing are stopped and popped off the stack. The behavior is not unlike that of exceptions in programming languages. Then the execution point is set so that any code waiting to execute (after all functions returned) is skipped. Thus, when bc(1) resets, it skips any remaining code waiting to be executed. Then, if it is interactive mode, and the error was not a fatal error (see the **EXIT STATUS** section), it asks for more input; otherwise, it exits with the appropriate return code. Note that this reset behavior is different from the GNU bc(1), which attempts to start executing the statement right after the one that caused an error. # PERFORMANCE Most bc(1) implementations use **char** types to calculate the value of **1** decimal digit at a time, but that can be slow. This bc(1) does something different. It uses large integers to calculate more than **1** decimal digit at a time. If built in a environment where **BC_LONG_BIT** (see the **LIMITS** section) is **64**, then each integer has **9** decimal digits. If built in an environment where **BC_LONG_BIT** is **32** then each integer has **4** decimal digits. This value (the number of decimal digits per large integer) is called **BC_BASE_DIGS**. The actual values of **BC_LONG_BIT** and **BC_BASE_DIGS** can be queried with the **limits** statement. In addition, this bc(1) uses an even larger integer for overflow checking. This integer type depends on the value of **BC_LONG_BIT**, but is always at least twice as large as the integer type used to store digits. # LIMITS The following are the limits on bc(1): **BC_LONG_BIT** : The number of bits in the **long** type in the environment where bc(1) was built. This determines how many decimal digits can be stored in a single large integer (see the **PERFORMANCE** section). **BC_BASE_DIGS** : The number of decimal digits per large integer (see the **PERFORMANCE** section). Depends on **BC_LONG_BIT**. **BC_BASE_POW** : The max decimal number that each large integer can store (see **BC_BASE_DIGS**) plus **1**. Depends on **BC_BASE_DIGS**. **BC_OVERFLOW_MAX** : The max number that the overflow type (see the **PERFORMANCE** section) can hold. Depends on **BC_LONG_BIT**. **BC_BASE_MAX** : The maximum output base. Set at **BC_BASE_POW**. **BC_DIM_MAX** : The maximum size of arrays. Set at **SIZE_MAX-1**. **BC_SCALE_MAX** : The maximum **scale**. Set at **BC_OVERFLOW_MAX-1**. **BC_STRING_MAX** : The maximum length of strings. Set at **BC_OVERFLOW_MAX-1**. **BC_NAME_MAX** : The maximum length of identifiers. Set at **BC_OVERFLOW_MAX-1**. **BC_NUM_MAX** : The maximum length of a number (in decimal digits), which includes digits after the decimal point. Set at **BC_OVERFLOW_MAX-1**. **BC_RAND_MAX** : The maximum integer (inclusive) returned by the **rand()** operand. Set at **2\^BC_LONG_BIT-1**. Exponent : The maximum allowable exponent (positive or negative). Set at **BC_OVERFLOW_MAX**. Number of vars : The maximum number of vars/arrays. Set at **SIZE_MAX-1**. The actual values can be queried with the **limits** statement. These limits are meant to be effectively non-existent; the limits are so large (at least on 64-bit machines) that there should not be any point at which they become a problem. In fact, memory should be exhausted before these limits should be hit. # ENVIRONMENT VARIABLES bc(1) recognizes the following environment variables: **POSIXLY_CORRECT** : If this variable exists (no matter the contents), bc(1) behaves as if the **-s** option was given. **BC_ENV_ARGS** : This is another way to give command-line arguments to bc(1). They should be in the same format as all other command-line arguments. These are always processed first, so any files given in **BC_ENV_ARGS** will be processed before arguments and files given on the command-line. This gives the user the ability to set up "standard" options and files to be used at every invocation. The most useful thing for such files to contain would be useful functions that the user might want every time bc(1) runs. The code that parses **BC_ENV_ARGS** will correctly handle quoted arguments, but it does not understand escape sequences. For example, the string **"/home/gavin/some bc file.bc"** will be correctly parsed, but the string **"/home/gavin/some \"bc\" file.bc"** will include the backslashes. The quote parsing will handle either kind of quotes, **'** or **"**. Thus, if you have a file with any number of single quotes in the name, you can use double quotes as the outside quotes, as in **"some 'bc' file.bc"**, and vice versa if you have a file with double quotes. However, handling a file with both kinds of quotes in **BC_ENV_ARGS** is not supported due to the complexity of the parsing, though such files are still supported on the command-line where the parsing is done by the shell. **BC_LINE_LENGTH** : If this environment variable exists and contains an integer that is greater than **1** and is less than **UINT16_MAX** (**2\^16-1**), bc(1) will output lines to that length, including the backslash (**\\**). The default line length is **70**. The special value of **0** will disable line length checking and print numbers without regard to line length and without backslashes and newlines. **BC_BANNER** : If this environment variable exists and contains an integer, then a non-zero value activates the copyright banner when bc(1) is in interactive mode, while zero deactivates it. If bc(1) is not in interactive mode (see the **INTERACTIVE MODE** section), then this environment variable has no effect because bc(1) does not print the banner when not in interactive mode. This environment variable overrides the default, which can be queried with the **-h** or **-\-help** options. **BC_SIGINT_RESET** : If bc(1) is not in interactive mode (see the **INTERACTIVE MODE** section), then this environment variable has no effect because bc(1) exits on **SIGINT** when not in interactive mode. However, when bc(1) is in interactive mode, then if this environment variable exists and contains an integer, a non-zero value makes bc(1) reset on **SIGINT**, rather than exit, and zero makes bc(1) exit. If this environment variable exists and is *not* an integer, then bc(1) will exit on **SIGINT**. This environment variable overrides the default, which can be queried with the **-h** or **-\-help** options. **BC_TTY_MODE** : If TTY mode is *not* available (see the **TTY MODE** section), then this environment variable has no effect. However, when TTY mode is available, then if this environment variable exists and contains an integer, then a non-zero value makes bc(1) use TTY mode, and zero makes bc(1) not use TTY mode. This environment variable overrides the default, which can be queried with the **-h** or **-\-help** options. **BC_PROMPT** : If TTY mode is *not* available (see the **TTY MODE** section), then this environment variable has no effect. However, when TTY mode is available, then if this environment variable exists and contains an integer, a non-zero value makes bc(1) use a prompt, and zero or a non-integer makes bc(1) not use a prompt. If this environment variable does not exist and **BC_TTY_MODE** does, then the value of the **BC_TTY_MODE** environment variable is used. This environment variable and the **BC_TTY_MODE** environment variable override the default, which can be queried with the **-h** or **-\-help** options. +**BC_EXPR_EXIT** + +: If any expressions or expression files are given on the command-line with + **-e**, **-\-expression**, **-f**, or **-\-file**, then if this environment + variable exists and contains an integer, a non-zero value makes bc(1) exit + after executing the expressions and expression files, and a non-zero value + makes bc(1) not exit. + + This environment variable overrides the default, which can be queried with + the **-h** or **-\-help** options. + # EXIT STATUS bc(1) returns the following exit statuses: **0** : No error. **1** : A math error occurred. This follows standard practice of using **1** for expected errors, since math errors will happen in the process of normal execution. Math errors include divide by **0**, taking the square root of a negative number, using a negative number as a bound for the pseudo-random number generator, attempting to convert a negative number to a hardware integer, overflow when converting a number to a hardware integer, overflow when calculating the size of a number, and attempting to use a non-integer where an integer is required. Converting to a hardware integer happens for the second operand of the power (**\^**), places (**\@**), left shift (**\<\<**), and right shift (**\>\>**) operators and their corresponding assignment operators. **2** : A parse error occurred. Parse errors include unexpected **EOF**, using an invalid character, failing to find the end of a string or comment, using a token where it is invalid, giving an invalid expression, giving an invalid print statement, giving an invalid function definition, attempting to assign to an expression that is not a named expression (see the *Named Expressions* subsection of the **SYNTAX** section), giving an invalid **auto** list, having a duplicate **auto**/function parameter, failing to find the end of a code block, attempting to return a value from a **void** function, attempting to use a variable as a reference, and using any extensions when the option **-s** or any equivalents were given. **3** : A runtime error occurred. Runtime errors include assigning an invalid number to any global (**ibase**, **obase**, or **scale**), giving a bad expression to a **read()** call, calling **read()** inside of a **read()** call, type errors, passing the wrong number of arguments to functions, attempting to call an undefined function, and attempting to use a **void** function call as a value in an expression. **4** : A fatal error occurred. Fatal errors include memory allocation errors, I/O errors, failing to open files, attempting to use files that do not have only ASCII characters (bc(1) only accepts ASCII characters), attempting to open a directory as a file, and giving invalid command-line options. The exit status **4** is special; when a fatal error occurs, bc(1) always exits and returns **4**, no matter what mode bc(1) is in. The other statuses will only be returned when bc(1) is not in interactive mode (see the **INTERACTIVE MODE** section), since bc(1) resets its state (see the **RESET** section) and accepts more input when one of those errors occurs in interactive mode. This is also the case when interactive mode is forced by the **-i** flag or **-\-interactive** option. These exit statuses allow bc(1) to be used in shell scripting with error checking, and its normal behavior can be forced by using the **-i** flag or **-\-interactive** option. # INTERACTIVE MODE Per the [standard][1], bc(1) has an interactive mode and a non-interactive mode. Interactive mode is turned on automatically when both **stdin** and **stdout** are hooked to a terminal, but the **-i** flag and **-\-interactive** option can turn it on in other situations. In interactive mode, bc(1) attempts to recover from errors (see the **RESET** section), and in normal execution, flushes **stdout** as soon as execution is done for the current input. bc(1) may also reset on **SIGINT** instead of exit, depending on the contents of, or default for, the **BC_SIGINT_RESET** environment variable (see the **ENVIRONMENT VARIABLES** section). # TTY MODE If **stdin**, **stdout**, and **stderr** are all connected to a TTY, then "TTY mode" is considered to be available, and thus, bc(1) can turn on TTY mode, subject to some settings. If there is the environment variable **BC_TTY_MODE** in the environment (see the **ENVIRONMENT VARIABLES** section), then if that environment variable contains a non-zero integer, bc(1) will turn on TTY mode when **stdin**, **stdout**, and **stderr** are all connected to a TTY. If the **BC_TTY_MODE** environment variable exists but is *not* a non-zero integer, then bc(1) will not turn TTY mode on. If the environment variable **BC_TTY_MODE** does *not* exist, the default setting is used. The default setting can be queried with the **-h** or **-\-help** options. TTY mode is different from interactive mode because interactive mode is required in the [bc(1) specification][1], and interactive mode requires only **stdin** and **stdout** to be connected to a terminal. ## Command-Line History Command-line history is only enabled if TTY mode is, i.e., that **stdin**, **stdout**, and **stderr** are connected to a TTY and the **BC_TTY_MODE** environment variable (see the **ENVIRONMENT VARIABLES** section) and its default do not disable TTY mode. See the **COMMAND LINE HISTORY** section for more information. ## Prompt If TTY mode is available, then a prompt can be enabled. Like TTY mode itself, it can be turned on or off with an environment variable: **BC_PROMPT** (see the **ENVIRONMENT VARIABLES** section). If the environment variable **BC_PROMPT** exists and is a non-zero integer, then the prompt is turned on when **stdin**, **stdout**, and **stderr** are connected to a TTY and the **-P** and **-\-no-prompt** options were not used. The read prompt will be turned on under the same conditions, except that the **-R** and **-\-no-read-prompt** options must also not be used. However, if **BC_PROMPT** does not exist, the prompt can be enabled or disabled with the **BC_TTY_MODE** environment variable, the **-P** and **-\-no-prompt** options, and the **-R** and **-\-no-read-prompt** options. See the **ENVIRONMENT VARIABLES** and **OPTIONS** sections for more details. # SIGNAL HANDLING Sending a **SIGINT** will cause bc(1) to do one of two things. If bc(1) is not in interactive mode (see the **INTERACTIVE MODE** section), or the **BC_SIGINT_RESET** environment variable (see the **ENVIRONMENT VARIABLES** section), or its default, is either not an integer or it is zero, bc(1) will exit. However, if bc(1) is in interactive mode, and the **BC_SIGINT_RESET** or its default is an integer and non-zero, then bc(1) will stop executing the current input and reset (see the **RESET** section) upon receiving a **SIGINT**. Note that "current input" can mean one of two things. If bc(1) is processing input from **stdin** in interactive mode, it will ask for more input. If bc(1) is processing input from a file in interactive mode, it will stop processing the file and start processing the next file, if one exists, or ask for input from **stdin** if no other file exists. This means that if a **SIGINT** is sent to bc(1) as it is executing a file, it can seem as though bc(1) did not respond to the signal since it will immediately start executing the next file. This is by design; most files that users execute when interacting with bc(1) have function definitions, which are quick to parse. If a file takes a long time to execute, there may be a bug in that file. The rest of the files could still be executed without problem, allowing the user to continue. **SIGTERM** and **SIGQUIT** cause bc(1) to clean up and exit, and it uses the default handler for all other signals. The one exception is **SIGHUP**; in that case, and only when bc(1) is in TTY mode (see the **TTY MODE** section), a **SIGHUP** will cause bc(1) to clean up and exit. # COMMAND LINE HISTORY bc(1) supports interactive command-line editing. If bc(1) can be in TTY mode (see the **TTY MODE** section), history can be enabled. This means that command-line history can only be enabled when **stdin**, **stdout**, and **stderr** are all connected to a TTY. Like TTY mode itself, it can be turned on or off with the environment variable **BC_TTY_MODE** (see the **ENVIRONMENT VARIABLES** section). If history is enabled, previous lines can be recalled and edited with the arrow keys. **Note**: tabs are converted to 8 spaces. # LOCALES This bc(1) ships with support for adding error messages for different locales and thus, supports **LC_MESSAGES**. # SEE ALSO dc(1) # STANDARDS bc(1) is compliant with the [IEEE Std 1003.1-2017 (“POSIX.1-2017”)][1] specification. The flags **-efghiqsvVw**, all long options, and the extensions noted above are extensions to that specification. Note that the specification explicitly says that bc(1) only accepts numbers that use a period (**.**) as a radix point, regardless of the value of **LC_NUMERIC**. This bc(1) supports error messages for different locales, and thus, it supports **LC_MESSAGES**. # BUGS None are known. Report bugs at https://git.yzena.com/gavin/bc. # AUTHORS Gavin D. Howard and contributors. [1]: https://pubs.opengroup.org/onlinepubs/9699919799/utilities/bc.html [2]: https://www.gnu.org/software/bc/ [3]: https://en.wikipedia.org/wiki/Rounding#Round_half_away_from_zero [4]: https://en.wikipedia.org/wiki/Unit_in_the_last_place [5]: https://people.eecs.berkeley.edu/~wkahan/LOG10HAF.TXT [6]: https://en.wikipedia.org/wiki/Rounding#Rounding_away_from_zero diff --git a/contrib/bc/manuals/bc/E.1 b/contrib/bc/manuals/bc/E.1 index bb563f5c96fc..6ee1e063ebde 100644 --- a/contrib/bc/manuals/bc/E.1 +++ b/contrib/bc/manuals/bc/E.1 @@ -1,1630 +1,1643 @@ .\" .\" SPDX-License-Identifier: BSD-2-Clause .\" .\" Copyright (c) 2018-2021 Gavin D. Howard and contributors. .\" .\" Redistribution and use in source and binary forms, with or without .\" modification, are permitted provided that the following conditions are met: .\" .\" * Redistributions of source code must retain the above copyright notice, .\" this list of conditions and the following disclaimer. .\" .\" * Redistributions in binary form must reproduce the above copyright notice, .\" this list of conditions and the following disclaimer in the documentation .\" and/or other materials provided with the distribution. .\" .\" THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" .\" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE .\" IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE .\" ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE .\" LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR .\" CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF .\" SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS .\" INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN .\" CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) .\" ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE .\" POSSIBILITY OF SUCH DAMAGE. .\" .TH "BC" "1" "June 2021" "Gavin D. Howard" "General Commands Manual" .SH NAME .PP bc - arbitrary-precision decimal arithmetic language and calculator .SH SYNOPSIS .PP \f[B]bc\f[R] [\f[B]-ghilPqRsvVw\f[R]] [\f[B]--global-stacks\f[R]] [\f[B]--help\f[R]] [\f[B]--interactive\f[R]] [\f[B]--mathlib\f[R]] [\f[B]--no-prompt\f[R]] [\f[B]--no-read-prompt\f[R]] [\f[B]--quiet\f[R]] [\f[B]--standard\f[R]] [\f[B]--warn\f[R]] [\f[B]--version\f[R]] [\f[B]-e\f[R] \f[I]expr\f[R]] [\f[B]--expression\f[R]=\f[I]expr\f[R]\&...] [\f[B]-f\f[R] \f[I]file\f[R]\&...] [\f[B]--file\f[R]=\f[I]file\f[R]\&...] [\f[I]file\f[R]\&...] .SH DESCRIPTION .PP bc(1) is an interactive processor for a language first standardized in 1991 by POSIX. (The current standard is here (https://pubs.opengroup.org/onlinepubs/9699919799/utilities/bc.html).) The language provides unlimited precision decimal arithmetic and is somewhat C-like, but there are differences. Such differences will be noted in this document. .PP After parsing and handling options, this bc(1) reads any files given on the command line and executes them before reading from \f[B]stdin\f[R]. .PP This bc(1) is a drop-in replacement for \f[I]any\f[R] bc(1), including (and especially) the GNU bc(1). .PP \f[B]Note\f[R]: If running this bc(1) on \f[I]any\f[R] script meant for another bc(1) gives a parse error, it is probably because a word this bc(1) reserves as a keyword is used as the name of a function, variable, or array. To fix that, use the command-line option \f[B]-r\f[R] \f[I]keyword\f[R], where \f[I]keyword\f[R] is the keyword that is used as a name in the script. For more information, see the \f[B]OPTIONS\f[R] section. .PP If parsing scripts meant for other bc(1) implementations still does not work, that is a bug and should be reported. See the \f[B]BUGS\f[R] section. .SH OPTIONS .PP The following are the options that bc(1) accepts. .TP \f[B]-g\f[R], \f[B]--global-stacks\f[R] Turns the globals \f[B]ibase\f[R], \f[B]obase\f[R], and \f[B]scale\f[R] into stacks. .RS .PP This has the effect that a copy of the current value of all three are pushed onto a stack for every function call, as well as popped when every function returns. This means that functions can assign to any and all of those globals without worrying that the change will affect other functions. Thus, a hypothetical function named \f[B]output(x,b)\f[R] that simply printed \f[B]x\f[R] in base \f[B]b\f[R] could be written like this: .IP .nf \f[C] define void output(x, b) { obase=b x } \f[R] .fi .PP instead of like this: .IP .nf \f[C] define void output(x, b) { auto c c=obase obase=b x obase=c } \f[R] .fi .PP This makes writing functions much easier. .PP However, since using this flag means that functions cannot set \f[B]ibase\f[R], \f[B]obase\f[R], or \f[B]scale\f[R] globally, functions that are made to do so cannot work anymore. There are two possible use cases for that, and each has a solution. .PP First, if a function is called on startup to turn bc(1) into a number converter, it is possible to replace that capability with various shell aliases. Examples: .IP .nf \f[C] alias d2o=\[dq]bc -e ibase=A -e obase=8\[dq] alias h2b=\[dq]bc -e ibase=G -e obase=2\[dq] \f[R] .fi .PP Second, if the purpose of a function is to set \f[B]ibase\f[R], \f[B]obase\f[R], or \f[B]scale\f[R] globally for any other purpose, it could be split into one to three functions (based on how many globals it sets) and each of those functions could return the desired value for a global. .PP If the behavior of this option is desired for every run of bc(1), then users could make sure to define \f[B]BC_ENV_ARGS\f[R] and include this option (see the \f[B]ENVIRONMENT VARIABLES\f[R] section for more details). .PP If \f[B]-s\f[R], \f[B]-w\f[R], or any equivalents are used, this option is ignored. .PP This is a \f[B]non-portable extension\f[R]. .RE .TP \f[B]-h\f[R], \f[B]--help\f[R] Prints a usage message and quits. .TP \f[B]-i\f[R], \f[B]--interactive\f[R] Forces interactive mode. (See the \f[B]INTERACTIVE MODE\f[R] section.) .RS .PP This is a \f[B]non-portable extension\f[R]. .RE .TP \f[B]-L\f[R], \f[B]--no-line-length\f[R] Disables line length checking and prints numbers without backslashes and newlines. In other words, this option sets \f[B]BC_LINE_LENGTH\f[R] to \f[B]0\f[R] (see the \f[B]ENVIRONMENT VARIABLES\f[R] section). .RS .PP This is a \f[B]non-portable extension\f[R]. .RE .TP \f[B]-l\f[R], \f[B]--mathlib\f[R] Sets \f[B]scale\f[R] (see the \f[B]SYNTAX\f[R] section) to \f[B]20\f[R] and loads the included math library before running any code, including any expressions or files specified on the command line. .RS .PP To learn what is in the library, see the \f[B]LIBRARY\f[R] section. .RE .TP \f[B]-P\f[R], \f[B]--no-prompt\f[R] Disables the prompt in TTY mode. (The prompt is only enabled in TTY mode. See the \f[B]TTY MODE\f[R] section.) This is mostly for those users that do not want a prompt or are not used to having them in bc(1). Most of those users would want to put this option in \f[B]BC_ENV_ARGS\f[R] (see the \f[B]ENVIRONMENT VARIABLES\f[R] section). .RS .PP These options override the \f[B]BC_PROMPT\f[R] and \f[B]BC_TTY_MODE\f[R] environment variables (see the \f[B]ENVIRONMENT VARIABLES\f[R] section). .PP This is a \f[B]non-portable extension\f[R]. .RE .TP \f[B]-R\f[R], \f[B]--no-read-prompt\f[R] Disables the read prompt in TTY mode. (The read prompt is only enabled in TTY mode. See the \f[B]TTY MODE\f[R] section.) This is mostly for those users that do not want a read prompt or are not used to having them in bc(1). Most of those users would want to put this option in \f[B]BC_ENV_ARGS\f[R] (see the \f[B]ENVIRONMENT VARIABLES\f[R] section). This option is also useful in hash bang lines of bc(1) scripts that prompt for user input. .RS .PP This option does not disable the regular prompt because the read prompt is only used when the \f[B]read()\f[R] built-in function is called. .PP These options \f[I]do\f[R] override the \f[B]BC_PROMPT\f[R] and \f[B]BC_TTY_MODE\f[R] environment variables (see the \f[B]ENVIRONMENT VARIABLES\f[R] section), but only for the read prompt. .PP This is a \f[B]non-portable extension\f[R]. .RE .TP \f[B]-r\f[R] \f[I]keyword\f[R], \f[B]--redefine\f[R]=\f[I]keyword\f[R] Redefines \f[I]keyword\f[R] in order to allow it to be used as a function, variable, or array name. This is useful when this bc(1) gives parse errors when parsing scripts meant for other bc(1) implementations. .RS .PP The keywords this bc(1) allows to be redefined are: .IP \[bu] 2 \f[B]abs\f[R] .IP \[bu] 2 \f[B]asciify\f[R] .IP \[bu] 2 \f[B]continue\f[R] .IP \[bu] 2 \f[B]divmod\f[R] .IP \[bu] 2 \f[B]else\f[R] .IP \[bu] 2 \f[B]halt\f[R] .IP \[bu] 2 \f[B]last\f[R] .IP \[bu] 2 \f[B]limits\f[R] .IP \[bu] 2 \f[B]maxibase\f[R] .IP \[bu] 2 \f[B]maxobase\f[R] .IP \[bu] 2 \f[B]maxscale\f[R] .IP \[bu] 2 \f[B]modexp\f[R] .IP \[bu] 2 \f[B]print\f[R] .IP \[bu] 2 \f[B]read\f[R] .IP \[bu] 2 \f[B]stream\f[R] .PP If any of those keywords are used as a function, variable, or array name in a script, use this option with the keyword as the argument. If multiple are used, use this option for all of them; it can be used multiple times. .PP Keywords are \f[I]not\f[R] redefined when parsing the builtin math library (see the \f[B]LIBRARY\f[R] section). .PP It is a fatal error to redefine keywords mandated by the POSIX standard. It is a fatal error to attempt to redefine words that this bc(1) does not reserve as keywords. .RE .TP \f[B]-q\f[R], \f[B]--quiet\f[R] This option is for compatibility with the GNU bc(1) (https://www.gnu.org/software/bc/); it is a no-op. Without this option, GNU bc(1) prints a copyright header. This bc(1) only prints the copyright header if one or more of the \f[B]-v\f[R], \f[B]-V\f[R], or \f[B]--version\f[R] options are given. .RS .PP This is a \f[B]non-portable extension\f[R]. .RE .TP \f[B]-s\f[R], \f[B]--standard\f[R] Process exactly the language defined by the standard (https://pubs.opengroup.org/onlinepubs/9699919799/utilities/bc.html) and error if any extensions are used. .RS .PP This is a \f[B]non-portable extension\f[R]. .RE .TP \f[B]-v\f[R], \f[B]-V\f[R], \f[B]--version\f[R] Print the version information (copyright header) and exit. .RS .PP This is a \f[B]non-portable extension\f[R]. .RE .TP \f[B]-w\f[R], \f[B]--warn\f[R] Like \f[B]-s\f[R] and \f[B]--standard\f[R], except that warnings (and not errors) are printed for non-standard extensions and execution continues normally. .RS .PP This is a \f[B]non-portable extension\f[R]. .RE .TP \f[B]-z\f[R], \f[B]--leading-zeroes\f[R] Makes bc(1) print all numbers greater than \f[B]-1\f[R] and less than \f[B]1\f[R], and not equal to \f[B]0\f[R], with a leading zero. .RS .PP This can be set for individual numbers with the \f[B]plz(x)\f[R], plznl(x)**, \f[B]pnlz(x)\f[R], and \f[B]pnlznl(x)\f[R] functions in the extended math library (see the \f[B]LIBRARY\f[R] section). .PP This is a \f[B]non-portable extension\f[R]. .RE .TP \f[B]-e\f[R] \f[I]expr\f[R], \f[B]--expression\f[R]=\f[I]expr\f[R] Evaluates \f[I]expr\f[R]. If multiple expressions are given, they are evaluated in order. If files are given as well (see below), the expressions and files are evaluated in the order given. This means that if a file is given before an expression, the file is read in and evaluated first. .RS .PP If this option is given on the command-line (i.e., not in \f[B]BC_ENV_ARGS\f[R], see the \f[B]ENVIRONMENT VARIABLES\f[R] section), then after processing all expressions and files, bc(1) will exit, unless \f[B]-\f[R] (\f[B]stdin\f[R]) was given as an argument at least once to \f[B]-f\f[R] or \f[B]--file\f[R], whether on the command-line or in \f[B]BC_ENV_ARGS\f[R]. However, if any other \f[B]-e\f[R], \f[B]--expression\f[R], \f[B]-f\f[R], or \f[B]--file\f[R] arguments are given after \f[B]-f-\f[R] or equivalent is given, bc(1) will give a fatal error and exit. .PP This is a \f[B]non-portable extension\f[R]. .RE .TP \f[B]-f\f[R] \f[I]file\f[R], \f[B]--file\f[R]=\f[I]file\f[R] Reads in \f[I]file\f[R] and evaluates it, line by line, as though it were read through \f[B]stdin\f[R]. If expressions are also given (see above), the expressions are evaluated in the order given. .RS .PP If this option is given on the command-line (i.e., not in \f[B]BC_ENV_ARGS\f[R], see the \f[B]ENVIRONMENT VARIABLES\f[R] section), then after processing all expressions and files, bc(1) will exit, unless \f[B]-\f[R] (\f[B]stdin\f[R]) was given as an argument at least once to \f[B]-f\f[R] or \f[B]--file\f[R]. However, if any other \f[B]-e\f[R], \f[B]--expression\f[R], \f[B]-f\f[R], or \f[B]--file\f[R] arguments are given after \f[B]-f-\f[R] or equivalent is given, bc(1) will give a fatal error and exit. .PP This is a \f[B]non-portable extension\f[R]. .RE .PP All long options are \f[B]non-portable extensions\f[R]. .SH STDIN .PP If no files or expressions are given by the \f[B]-f\f[R], \f[B]--file\f[R], \f[B]-e\f[R], or \f[B]--expression\f[R] options, then bc(1) read from \f[B]stdin\f[R]. .PP However, there are a few caveats to this. .PP First, \f[B]stdin\f[R] is evaluated a line at a time. The only exception to this is if the parse cannot complete. That means that starting a string without ending it or starting a function, \f[B]if\f[R] statement, or loop without ending it will also cause bc(1) to not execute. .PP Second, after an \f[B]if\f[R] statement, bc(1) doesn\[cq]t know if an \f[B]else\f[R] statement will follow, so it will not execute until it knows there will not be an \f[B]else\f[R] statement. .SH STDOUT .PP Any non-error output is written to \f[B]stdout\f[R]. In addition, if history (see the \f[B]HISTORY\f[R] section) and the prompt (see the \f[B]TTY MODE\f[R] section) are enabled, both are output to \f[B]stdout\f[R]. .PP \f[B]Note\f[R]: Unlike other bc(1) implementations, this bc(1) will issue a fatal error (see the \f[B]EXIT STATUS\f[R] section) if it cannot write to \f[B]stdout\f[R], so if \f[B]stdout\f[R] is closed, as in \f[B]bc >&-\f[R], it will quit with an error. This is done so that bc(1) can report problems when \f[B]stdout\f[R] is redirected to a file. .PP If there are scripts that depend on the behavior of other bc(1) implementations, it is recommended that those scripts be changed to redirect \f[B]stdout\f[R] to \f[B]/dev/null\f[R]. .SH STDERR .PP Any error output is written to \f[B]stderr\f[R]. .PP \f[B]Note\f[R]: Unlike other bc(1) implementations, this bc(1) will issue a fatal error (see the \f[B]EXIT STATUS\f[R] section) if it cannot write to \f[B]stderr\f[R], so if \f[B]stderr\f[R] is closed, as in \f[B]bc 2>&-\f[R], it will quit with an error. This is done so that bc(1) can exit with an error code when \f[B]stderr\f[R] is redirected to a file. .PP If there are scripts that depend on the behavior of other bc(1) implementations, it is recommended that those scripts be changed to redirect \f[B]stderr\f[R] to \f[B]/dev/null\f[R]. .SH SYNTAX .PP The syntax for bc(1) programs is mostly C-like, with some differences. This bc(1) follows the POSIX standard (https://pubs.opengroup.org/onlinepubs/9699919799/utilities/bc.html), which is a much more thorough resource for the language this bc(1) accepts. This section is meant to be a summary and a listing of all the extensions to the standard. .PP In the sections below, \f[B]E\f[R] means expression, \f[B]S\f[R] means statement, and \f[B]I\f[R] means identifier. .PP Identifiers (\f[B]I\f[R]) start with a lowercase letter and can be followed by any number (up to \f[B]BC_NAME_MAX-1\f[R]) of lowercase letters (\f[B]a-z\f[R]), digits (\f[B]0-9\f[R]), and underscores (\f[B]_\f[R]). The regex is \f[B][a-z][a-z0-9_]*\f[R]. Identifiers with more than one character (letter) are a \f[B]non-portable extension\f[R]. .PP \f[B]ibase\f[R] is a global variable determining how to interpret constant numbers. It is the \[lq]input\[rq] base, or the number base used for interpreting input numbers. \f[B]ibase\f[R] is initially \f[B]10\f[R]. If the \f[B]-s\f[R] (\f[B]--standard\f[R]) and \f[B]-w\f[R] (\f[B]--warn\f[R]) flags were not given on the command line, the max allowable value for \f[B]ibase\f[R] is \f[B]36\f[R]. Otherwise, it is \f[B]16\f[R]. The min allowable value for \f[B]ibase\f[R] is \f[B]2\f[R]. The max allowable value for \f[B]ibase\f[R] can be queried in bc(1) programs with the \f[B]maxibase()\f[R] built-in function. .PP \f[B]obase\f[R] is a global variable determining how to output results. It is the \[lq]output\[rq] base, or the number base used for outputting numbers. \f[B]obase\f[R] is initially \f[B]10\f[R]. The max allowable value for \f[B]obase\f[R] is \f[B]BC_BASE_MAX\f[R] and can be queried in bc(1) programs with the \f[B]maxobase()\f[R] built-in function. The min allowable value for \f[B]obase\f[R] is \f[B]2\f[R]. Values are output in the specified base. .PP The \f[I]scale\f[R] of an expression is the number of digits in the result of the expression right of the decimal point, and \f[B]scale\f[R] is a global variable that sets the precision of any operations, with exceptions. \f[B]scale\f[R] is initially \f[B]0\f[R]. \f[B]scale\f[R] cannot be negative. The max allowable value for \f[B]scale\f[R] is \f[B]BC_SCALE_MAX\f[R] and can be queried in bc(1) programs with the \f[B]maxscale()\f[R] built-in function. .PP bc(1) has both \f[I]global\f[R] variables and \f[I]local\f[R] variables. All \f[I]local\f[R] variables are local to the function; they are parameters or are introduced in the \f[B]auto\f[R] list of a function (see the \f[B]FUNCTIONS\f[R] section). If a variable is accessed which is not a parameter or in the \f[B]auto\f[R] list, it is assumed to be \f[I]global\f[R]. If a parent function has a \f[I]local\f[R] variable version of a variable that a child function considers \f[I]global\f[R], the value of that \f[I]global\f[R] variable in the child function is the value of the variable in the parent function, not the value of the actual \f[I]global\f[R] variable. .PP All of the above applies to arrays as well. .PP The value of a statement that is an expression (i.e., any of the named expressions or operands) is printed unless the lowest precedence operator is an assignment operator \f[I]and\f[R] the expression is notsurrounded by parentheses. .PP The value that is printed is also assigned to the special variable \f[B]last\f[R]. A single dot (\f[B].\f[R]) may also be used as a synonym for \f[B]last\f[R]. These are \f[B]non-portable extensions\f[R]. .PP Either semicolons or newlines may separate statements. .SS Comments .PP There are two kinds of comments: .IP "1." 3 Block comments are enclosed in \f[B]/*\f[R] and \f[B]*/\f[R]. .IP "2." 3 Line comments go from \f[B]#\f[R] until, and not including, the next newline. This is a \f[B]non-portable extension\f[R]. .SS Named Expressions .PP The following are named expressions in bc(1): .IP "1." 3 Variables: \f[B]I\f[R] .IP "2." 3 Array Elements: \f[B]I[E]\f[R] .IP "3." 3 \f[B]ibase\f[R] .IP "4." 3 \f[B]obase\f[R] .IP "5." 3 \f[B]scale\f[R] .IP "6." 3 \f[B]last\f[R] or a single dot (\f[B].\f[R]) .PP Number 6 is a \f[B]non-portable extension\f[R]. .PP Variables and arrays do not interfere; users can have arrays named the same as variables. This also applies to functions (see the \f[B]FUNCTIONS\f[R] section), so a user can have a variable, array, and function that all have the same name, and they will not shadow each other, whether inside of functions or not. .PP Named expressions are required as the operand of \f[B]increment\f[R]/\f[B]decrement\f[R] operators and as the left side of \f[B]assignment\f[R] operators (see the \f[I]Operators\f[R] subsection). .SS Operands .PP The following are valid operands in bc(1): .IP " 1." 4 Numbers (see the \f[I]Numbers\f[R] subsection below). .IP " 2." 4 Array indices (\f[B]I[E]\f[R]). .IP " 3." 4 \f[B](E)\f[R]: The value of \f[B]E\f[R] (used to change precedence). .IP " 4." 4 \f[B]sqrt(E)\f[R]: The square root of \f[B]E\f[R]. \f[B]E\f[R] must be non-negative. .IP " 5." 4 \f[B]length(E)\f[R]: The number of significant decimal digits in \f[B]E\f[R]. Returns \f[B]1\f[R] for \f[B]0\f[R] with no decimal places. If given a string, the length of the string is returned. Passing a string to \f[B]length(E)\f[R] is a \f[B]non-portable extension\f[R]. .IP " 6." 4 \f[B]length(I[])\f[R]: The number of elements in the array \f[B]I\f[R]. This is a \f[B]non-portable extension\f[R]. .IP " 7." 4 \f[B]scale(E)\f[R]: The \f[I]scale\f[R] of \f[B]E\f[R]. .IP " 8." 4 \f[B]abs(E)\f[R]: The absolute value of \f[B]E\f[R]. This is a \f[B]non-portable extension\f[R]. .IP " 9." 4 \f[B]modexp(E, E, E)\f[R]: Modular exponentiation, where the first expression is the base, the second is the exponent, and the third is the modulus. All three values must be integers. The second argument must be non-negative. The third argument must be non-zero. This is a \f[B]non-portable extension\f[R]. .IP "10." 4 \f[B]divmod(E, E, I[])\f[R]: Division and modulus in one operation. This is for optimization. The first expression is the dividend, and the second is the divisor, which must be non-zero. The return value is the quotient, and the modulus is stored in index \f[B]0\f[R] of the provided array (the last argument). This is a \f[B]non-portable extension\f[R]. .IP "11." 4 \f[B]asciify(E)\f[R]: If \f[B]E\f[R] is a string, returns a string that is the first letter of its argument. If it is a number, calculates the number mod \f[B]256\f[R] and returns that number as a one-character string. This is a \f[B]non-portable extension\f[R]. .IP "12." 4 \f[B]I()\f[R], \f[B]I(E)\f[R], \f[B]I(E, E)\f[R], and so on, where \f[B]I\f[R] is an identifier for a non-\f[B]void\f[R] function (see the \f[I]Void Functions\f[R] subsection of the \f[B]FUNCTIONS\f[R] section). The \f[B]E\f[R] argument(s) may also be arrays of the form \f[B]I[]\f[R], which will automatically be turned into array references (see the \f[I]Array References\f[R] subsection of the \f[B]FUNCTIONS\f[R] section) if the corresponding parameter in the function definition is an array reference. .IP "13." 4 \f[B]read()\f[R]: Reads a line from \f[B]stdin\f[R] and uses that as an expression. The result of that expression is the result of the \f[B]read()\f[R] operand. This is a \f[B]non-portable extension\f[R]. .IP "14." 4 \f[B]maxibase()\f[R]: The max allowable \f[B]ibase\f[R]. This is a \f[B]non-portable extension\f[R]. .IP "15." 4 \f[B]maxobase()\f[R]: The max allowable \f[B]obase\f[R]. This is a \f[B]non-portable extension\f[R]. .IP "16." 4 \f[B]maxscale()\f[R]: The max allowable \f[B]scale\f[R]. This is a \f[B]non-portable extension\f[R]. .IP "17." 4 \f[B]line_length()\f[R]: The line length set with \f[B]BC_LINE_LENGTH\f[R] (see the \f[B]ENVIRONMENT VARIABLES\f[R] section). This is a \f[B]non-portable extension\f[R]. .IP "18." 4 \f[B]global_stacks()\f[R]: \f[B]0\f[R] if global stacks are not enabled with the \f[B]-g\f[R] or \f[B]--global-stacks\f[R] options, non-zero otherwise. See the \f[B]OPTIONS\f[R] section. This is a \f[B]non-portable extension\f[R]. .IP "19." 4 \f[B]leading_zero()\f[R]: \f[B]0\f[R] if leading zeroes are not enabled with the \f[B]-z\f[R] or \f[B]\[en]leading-zeroes\f[R] options, non-zero otherwise. See the \f[B]OPTIONS\f[R] section. This is a \f[B]non-portable extension\f[R]. .SS Numbers .PP Numbers are strings made up of digits, uppercase letters, and at most \f[B]1\f[R] period for a radix. Numbers can have up to \f[B]BC_NUM_MAX\f[R] digits. Uppercase letters are equal to \f[B]9\f[R] + their position in the alphabet (i.e., \f[B]A\f[R] equals \f[B]10\f[R], or \f[B]9+1\f[R]). If a digit or letter makes no sense with the current value of \f[B]ibase\f[R], they are set to the value of the highest valid digit in \f[B]ibase\f[R]. .PP Single-character numbers (i.e., \f[B]A\f[R] alone) take the value that they would have if they were valid digits, regardless of the value of \f[B]ibase\f[R]. This means that \f[B]A\f[R] alone always equals decimal \f[B]10\f[R] and \f[B]Z\f[R] alone always equals decimal \f[B]35\f[R]. .SS Operators .PP The following arithmetic and logical operators can be used. They are listed in order of decreasing precedence. Operators in the same group have the same precedence. .TP \f[B]++\f[R] \f[B]--\f[R] Type: Prefix and Postfix .RS .PP Associativity: None .PP Description: \f[B]increment\f[R], \f[B]decrement\f[R] .RE .TP \f[B]-\f[R] \f[B]!\f[R] Type: Prefix .RS .PP Associativity: None .PP Description: \f[B]negation\f[R], \f[B]boolean not\f[R] .RE .TP \f[B]\[ha]\f[R] Type: Binary .RS .PP Associativity: Right .PP Description: \f[B]power\f[R] .RE .TP \f[B]*\f[R] \f[B]/\f[R] \f[B]%\f[R] Type: Binary .RS .PP Associativity: Left .PP Description: \f[B]multiply\f[R], \f[B]divide\f[R], \f[B]modulus\f[R] .RE .TP \f[B]+\f[R] \f[B]-\f[R] Type: Binary .RS .PP Associativity: Left .PP Description: \f[B]add\f[R], \f[B]subtract\f[R] .RE .TP \f[B]=\f[R] \f[B]+=\f[R] \f[B]-=\f[R] \f[B]*=\f[R] \f[B]/=\f[R] \f[B]%=\f[R] \f[B]\[ha]=\f[R] Type: Binary .RS .PP Associativity: Right .PP Description: \f[B]assignment\f[R] .RE .TP \f[B]==\f[R] \f[B]<=\f[R] \f[B]>=\f[R] \f[B]!=\f[R] \f[B]<\f[R] \f[B]>\f[R] Type: Binary .RS .PP Associativity: Left .PP Description: \f[B]relational\f[R] .RE .TP \f[B]&&\f[R] Type: Binary .RS .PP Associativity: Left .PP Description: \f[B]boolean and\f[R] .RE .TP \f[B]||\f[R] Type: Binary .RS .PP Associativity: Left .PP Description: \f[B]boolean or\f[R] .RE .PP The operators will be described in more detail below. .TP \f[B]++\f[R] \f[B]--\f[R] The prefix and postfix \f[B]increment\f[R] and \f[B]decrement\f[R] operators behave exactly like they would in C. They require a named expression (see the \f[I]Named Expressions\f[R] subsection) as an operand. .RS .PP The prefix versions of these operators are more efficient; use them where possible. .RE .TP \f[B]-\f[R] The \f[B]negation\f[R] operator returns \f[B]0\f[R] if a user attempts to negate any expression with the value \f[B]0\f[R]. Otherwise, a copy of the expression with its sign flipped is returned. .TP \f[B]!\f[R] The \f[B]boolean not\f[R] operator returns \f[B]1\f[R] if the expression is \f[B]0\f[R], or \f[B]0\f[R] otherwise. .RS .PP This is a \f[B]non-portable extension\f[R]. .RE .TP \f[B]\[ha]\f[R] The \f[B]power\f[R] operator (not the \f[B]exclusive or\f[R] operator, as it would be in C) takes two expressions and raises the first to the power of the value of the second. The \f[I]scale\f[R] of the result is equal to \f[B]scale\f[R]. .RS .PP The second expression must be an integer (no \f[I]scale\f[R]), and if it is negative, the first value must be non-zero. .RE .TP \f[B]*\f[R] The \f[B]multiply\f[R] operator takes two expressions, multiplies them, and returns the product. If \f[B]a\f[R] is the \f[I]scale\f[R] of the first expression and \f[B]b\f[R] is the \f[I]scale\f[R] of the second expression, the \f[I]scale\f[R] of the result is equal to \f[B]min(a+b,max(scale,a,b))\f[R] where \f[B]min()\f[R] and \f[B]max()\f[R] return the obvious values. .TP \f[B]/\f[R] The \f[B]divide\f[R] operator takes two expressions, divides them, and returns the quotient. The \f[I]scale\f[R] of the result shall be the value of \f[B]scale\f[R]. .RS .PP The second expression must be non-zero. .RE .TP \f[B]%\f[R] The \f[B]modulus\f[R] operator takes two expressions, \f[B]a\f[R] and \f[B]b\f[R], and evaluates them by 1) Computing \f[B]a/b\f[R] to current \f[B]scale\f[R] and 2) Using the result of step 1 to calculate \f[B]a-(a/b)*b\f[R] to \f[I]scale\f[R] \f[B]max(scale+scale(b),scale(a))\f[R]. .RS .PP The second expression must be non-zero. .RE .TP \f[B]+\f[R] The \f[B]add\f[R] operator takes two expressions, \f[B]a\f[R] and \f[B]b\f[R], and returns the sum, with a \f[I]scale\f[R] equal to the max of the \f[I]scale\f[R]s of \f[B]a\f[R] and \f[B]b\f[R]. .TP \f[B]-\f[R] The \f[B]subtract\f[R] operator takes two expressions, \f[B]a\f[R] and \f[B]b\f[R], and returns the difference, with a \f[I]scale\f[R] equal to the max of the \f[I]scale\f[R]s of \f[B]a\f[R] and \f[B]b\f[R]. .TP \f[B]=\f[R] \f[B]+=\f[R] \f[B]-=\f[R] \f[B]*=\f[R] \f[B]/=\f[R] \f[B]%=\f[R] \f[B]\[ha]=\f[R] The \f[B]assignment\f[R] operators take two expressions, \f[B]a\f[R] and \f[B]b\f[R] where \f[B]a\f[R] is a named expression (see the \f[I]Named Expressions\f[R] subsection). .RS .PP For \f[B]=\f[R], \f[B]b\f[R] is copied and the result is assigned to \f[B]a\f[R]. For all others, \f[B]a\f[R] and \f[B]b\f[R] are applied as operands to the corresponding arithmetic operator and the result is assigned to \f[B]a\f[R]. .RE .TP \f[B]==\f[R] \f[B]<=\f[R] \f[B]>=\f[R] \f[B]!=\f[R] \f[B]<\f[R] \f[B]>\f[R] The \f[B]relational\f[R] operators compare two expressions, \f[B]a\f[R] and \f[B]b\f[R], and if the relation holds, according to C language semantics, the result is \f[B]1\f[R]. Otherwise, it is \f[B]0\f[R]. .RS .PP Note that unlike in C, these operators have a lower precedence than the \f[B]assignment\f[R] operators, which means that \f[B]a=b>c\f[R] is interpreted as \f[B](a=b)>c\f[R]. .PP Also, unlike the standard (https://pubs.opengroup.org/onlinepubs/9699919799/utilities/bc.html) requires, these operators can appear anywhere any other expressions can be used. This allowance is a \f[B]non-portable extension\f[R]. .RE .TP \f[B]&&\f[R] The \f[B]boolean and\f[R] operator takes two expressions and returns \f[B]1\f[R] if both expressions are non-zero, \f[B]0\f[R] otherwise. .RS .PP This is \f[I]not\f[R] a short-circuit operator. .PP This is a \f[B]non-portable extension\f[R]. .RE .TP \f[B]||\f[R] The \f[B]boolean or\f[R] operator takes two expressions and returns \f[B]1\f[R] if one of the expressions is non-zero, \f[B]0\f[R] otherwise. .RS .PP This is \f[I]not\f[R] a short-circuit operator. .PP This is a \f[B]non-portable extension\f[R]. .RE .SS Statements .PP The following items are statements: .IP " 1." 4 \f[B]E\f[R] .IP " 2." 4 \f[B]{\f[R] \f[B]S\f[R] \f[B];\f[R] \&... \f[B];\f[R] \f[B]S\f[R] \f[B]}\f[R] .IP " 3." 4 \f[B]if\f[R] \f[B](\f[R] \f[B]E\f[R] \f[B])\f[R] \f[B]S\f[R] .IP " 4." 4 \f[B]if\f[R] \f[B](\f[R] \f[B]E\f[R] \f[B])\f[R] \f[B]S\f[R] \f[B]else\f[R] \f[B]S\f[R] .IP " 5." 4 \f[B]while\f[R] \f[B](\f[R] \f[B]E\f[R] \f[B])\f[R] \f[B]S\f[R] .IP " 6." 4 \f[B]for\f[R] \f[B](\f[R] \f[B]E\f[R] \f[B];\f[R] \f[B]E\f[R] \f[B];\f[R] \f[B]E\f[R] \f[B])\f[R] \f[B]S\f[R] .IP " 7." 4 An empty statement .IP " 8." 4 \f[B]break\f[R] .IP " 9." 4 \f[B]continue\f[R] .IP "10." 4 \f[B]quit\f[R] .IP "11." 4 \f[B]halt\f[R] .IP "12." 4 \f[B]limits\f[R] .IP "13." 4 A string of characters, enclosed in double quotes .IP "14." 4 \f[B]print\f[R] \f[B]E\f[R] \f[B],\f[R] \&... \f[B],\f[R] \f[B]E\f[R] .IP "15." 4 \f[B]stream\f[R] \f[B]E\f[R] \f[B],\f[R] \&... \f[B],\f[R] \f[B]E\f[R] .IP "16." 4 \f[B]I()\f[R], \f[B]I(E)\f[R], \f[B]I(E, E)\f[R], and so on, where \f[B]I\f[R] is an identifier for a \f[B]void\f[R] function (see the \f[I]Void Functions\f[R] subsection of the \f[B]FUNCTIONS\f[R] section). The \f[B]E\f[R] argument(s) may also be arrays of the form \f[B]I[]\f[R], which will automatically be turned into array references (see the \f[I]Array References\f[R] subsection of the \f[B]FUNCTIONS\f[R] section) if the corresponding parameter in the function definition is an array reference. .PP Numbers 4, 9, 11, 12, 14, 15, and 16 are \f[B]non-portable extensions\f[R]. .PP Also, as a \f[B]non-portable extension\f[R], any or all of the expressions in the header of a for loop may be omitted. If the condition (second expression) is omitted, it is assumed to be a constant \f[B]1\f[R]. .PP The \f[B]break\f[R] statement causes a loop to stop iterating and resume execution immediately following a loop. This is only allowed in loops. .PP The \f[B]continue\f[R] statement causes a loop iteration to stop early and returns to the start of the loop, including testing the loop condition. This is only allowed in loops. .PP The \f[B]if\f[R] \f[B]else\f[R] statement does the same thing as in C. .PP The \f[B]quit\f[R] statement causes bc(1) to quit, even if it is on a branch that will not be executed (it is a compile-time command). .PP The \f[B]halt\f[R] statement causes bc(1) to quit, if it is executed. (Unlike \f[B]quit\f[R] if it is on a branch of an \f[B]if\f[R] statement that is not executed, bc(1) does not quit.) .PP The \f[B]limits\f[R] statement prints the limits that this bc(1) is subject to. This is like the \f[B]quit\f[R] statement in that it is a compile-time command. .PP An expression by itself is evaluated and printed, followed by a newline. .SS Strings .PP If strings appear as a statement by themselves, they are printed without a trailing newline. .PP In addition to appearing as a lone statement by themselves, strings can be assigned to variables and array elements. They can also be passed to functions in variable parameters. .PP If any statement that expects a string is given a variable that had a string assigned to it, the statement acts as though it had received a string. .PP If any math operation is attempted on a string or a variable or array element that has been assigned a string, an error is raised, and bc(1) resets (see the \f[B]RESET\f[R] section). .PP Assigning strings to variables and array elements and passing them to functions are \f[B]non-portable extensions\f[R]. .SS Print Statement .PP The \[lq]expressions\[rq] in a \f[B]print\f[R] statement may also be strings. If they are, there are backslash escape sequences that are interpreted specially. What those sequences are, and what they cause to be printed, are shown below: .PP \f[B]\[rs]a\f[R]: \f[B]\[rs]a\f[R] .PP \f[B]\[rs]b\f[R]: \f[B]\[rs]b\f[R] .PP \f[B]\[rs]\[rs]\f[R]: \f[B]\[rs]\f[R] .PP \f[B]\[rs]e\f[R]: \f[B]\[rs]\f[R] .PP \f[B]\[rs]f\f[R]: \f[B]\[rs]f\f[R] .PP \f[B]\[rs]n\f[R]: \f[B]\[rs]n\f[R] .PP \f[B]\[rs]q\f[R]: \f[B]\[lq]\f[R] .PP \f[B]\[rs]r\f[R]: \f[B]\[rs]r\f[R] .PP \f[B]\[rs]t\f[R]: \f[B]\[rs]t\f[R] .PP Any other character following a backslash causes the backslash and character to be printed as-is. .PP Any non-string expression in a print statement shall be assigned to \f[B]last\f[R], like any other expression that is printed. .SS Stream Statement .PP The \[lq]expressions in a \f[B]stream\f[R] statement may also be strings. .PP If a \f[B]stream\f[R] statement is given a string, it prints the string as though the string had appeared as its own statement. In other words, the \f[B]stream\f[R] statement prints strings normally, without a newline. .PP If a \f[B]stream\f[R] statement is given a number, a copy of it is truncated and its absolute value is calculated. The result is then printed as though \f[B]obase\f[R] is \f[B]256\f[R] and each digit is interpreted as an 8-bit ASCII character, making it a byte stream. .SS Order of Evaluation .PP All expressions in a statment are evaluated left to right, except as necessary to maintain order of operations. This means, for example, assuming that \f[B]i\f[R] is equal to \f[B]0\f[R], in the expression .IP .nf \f[C] a[i++] = i++ \f[R] .fi .PP the first (or 0th) element of \f[B]a\f[R] is set to \f[B]1\f[R], and \f[B]i\f[R] is equal to \f[B]2\f[R] at the end of the expression. .PP This includes function arguments. Thus, assuming \f[B]i\f[R] is equal to \f[B]0\f[R], this means that in the expression .IP .nf \f[C] x(i++, i++) \f[R] .fi .PP the first argument passed to \f[B]x()\f[R] is \f[B]0\f[R], and the second argument is \f[B]1\f[R], while \f[B]i\f[R] is equal to \f[B]2\f[R] before the function starts executing. .SH FUNCTIONS .PP Function definitions are as follows: .IP .nf \f[C] define I(I,...,I){ auto I,...,I S;...;S return(E) } \f[R] .fi .PP Any \f[B]I\f[R] in the parameter list or \f[B]auto\f[R] list may be replaced with \f[B]I[]\f[R] to make a parameter or \f[B]auto\f[R] var an array, and any \f[B]I\f[R] in the parameter list may be replaced with \f[B]*I[]\f[R] to make a parameter an array reference. Callers of functions that take array references should not put an asterisk in the call; they must be called with just \f[B]I[]\f[R] like normal array parameters and will be automatically converted into references. .PP As a \f[B]non-portable extension\f[R], the opening brace of a \f[B]define\f[R] statement may appear on the next line. .PP As a \f[B]non-portable extension\f[R], the return statement may also be in one of the following forms: .IP "1." 3 \f[B]return\f[R] .IP "2." 3 \f[B]return\f[R] \f[B](\f[R] \f[B])\f[R] .IP "3." 3 \f[B]return\f[R] \f[B]E\f[R] .PP The first two, or not specifying a \f[B]return\f[R] statement, is equivalent to \f[B]return (0)\f[R], unless the function is a \f[B]void\f[R] function (see the \f[I]Void Functions\f[R] subsection below). .SS Void Functions .PP Functions can also be \f[B]void\f[R] functions, defined as follows: .IP .nf \f[C] define void I(I,...,I){ auto I,...,I S;...;S return } \f[R] .fi .PP They can only be used as standalone expressions, where such an expression would be printed alone, except in a print statement. .PP Void functions can only use the first two \f[B]return\f[R] statements listed above. They can also omit the return statement entirely. .PP The word \[lq]void\[rq] is not treated as a keyword; it is still possible to have variables, arrays, and functions named \f[B]void\f[R]. The word \[lq]void\[rq] is only treated specially right after the \f[B]define\f[R] keyword. .PP This is a \f[B]non-portable extension\f[R]. .SS Array References .PP For any array in the parameter list, if the array is declared in the form .IP .nf \f[C] *I[] \f[R] .fi .PP it is a \f[B]reference\f[R]. Any changes to the array in the function are reflected, when the function returns, to the array that was passed in. .PP Other than this, all function arguments are passed by value. .PP This is a \f[B]non-portable extension\f[R]. .SH LIBRARY .PP All of the functions below are available when the \f[B]-l\f[R] or \f[B]--mathlib\f[R] command-line flags are given. .SS Standard Library .PP The standard (https://pubs.opengroup.org/onlinepubs/9699919799/utilities/bc.html) defines the following functions for the math library: .TP \f[B]s(x)\f[R] Returns the sine of \f[B]x\f[R], which is assumed to be in radians. .RS .PP This is a transcendental function (see the \f[I]Transcendental Functions\f[R] subsection below). .RE .TP \f[B]c(x)\f[R] Returns the cosine of \f[B]x\f[R], which is assumed to be in radians. .RS .PP This is a transcendental function (see the \f[I]Transcendental Functions\f[R] subsection below). .RE .TP \f[B]a(x)\f[R] Returns the arctangent of \f[B]x\f[R], in radians. .RS .PP This is a transcendental function (see the \f[I]Transcendental Functions\f[R] subsection below). .RE .TP \f[B]l(x)\f[R] Returns the natural logarithm of \f[B]x\f[R]. .RS .PP This is a transcendental function (see the \f[I]Transcendental Functions\f[R] subsection below). .RE .TP \f[B]e(x)\f[R] Returns the mathematical constant \f[B]e\f[R] raised to the power of \f[B]x\f[R]. .RS .PP This is a transcendental function (see the \f[I]Transcendental Functions\f[R] subsection below). .RE .TP \f[B]j(x, n)\f[R] Returns the bessel integer order \f[B]n\f[R] (truncated) of \f[B]x\f[R]. .RS .PP This is a transcendental function (see the \f[I]Transcendental Functions\f[R] subsection below). .RE .SS Transcendental Functions .PP All transcendental functions can return slightly inaccurate results (up to 1 ULP (https://en.wikipedia.org/wiki/Unit_in_the_last_place)). This is unavoidable, and this article (https://people.eecs.berkeley.edu/~wkahan/LOG10HAF.TXT) explains why it is impossible and unnecessary to calculate exact results for the transcendental functions. .PP Because of the possible inaccuracy, I recommend that users call those functions with the precision (\f[B]scale\f[R]) set to at least 1 higher than is necessary. If exact results are \f[I]absolutely\f[R] required, users can double the precision (\f[B]scale\f[R]) and then truncate. .PP The transcendental functions in the standard math library are: .IP \[bu] 2 \f[B]s(x)\f[R] .IP \[bu] 2 \f[B]c(x)\f[R] .IP \[bu] 2 \f[B]a(x)\f[R] .IP \[bu] 2 \f[B]l(x)\f[R] .IP \[bu] 2 \f[B]e(x)\f[R] .IP \[bu] 2 \f[B]j(x, n)\f[R] .SH RESET .PP When bc(1) encounters an error or a signal that it has a non-default handler for, it resets. This means that several things happen. .PP First, any functions that are executing are stopped and popped off the stack. The behavior is not unlike that of exceptions in programming languages. Then the execution point is set so that any code waiting to execute (after all functions returned) is skipped. .PP Thus, when bc(1) resets, it skips any remaining code waiting to be executed. Then, if it is interactive mode, and the error was not a fatal error (see the \f[B]EXIT STATUS\f[R] section), it asks for more input; otherwise, it exits with the appropriate return code. .PP Note that this reset behavior is different from the GNU bc(1), which attempts to start executing the statement right after the one that caused an error. .SH PERFORMANCE .PP Most bc(1) implementations use \f[B]char\f[R] types to calculate the value of \f[B]1\f[R] decimal digit at a time, but that can be slow. This bc(1) does something different. .PP It uses large integers to calculate more than \f[B]1\f[R] decimal digit at a time. If built in a environment where \f[B]BC_LONG_BIT\f[R] (see the \f[B]LIMITS\f[R] section) is \f[B]64\f[R], then each integer has \f[B]9\f[R] decimal digits. If built in an environment where \f[B]BC_LONG_BIT\f[R] is \f[B]32\f[R] then each integer has \f[B]4\f[R] decimal digits. This value (the number of decimal digits per large integer) is called \f[B]BC_BASE_DIGS\f[R]. .PP The actual values of \f[B]BC_LONG_BIT\f[R] and \f[B]BC_BASE_DIGS\f[R] can be queried with the \f[B]limits\f[R] statement. .PP In addition, this bc(1) uses an even larger integer for overflow checking. This integer type depends on the value of \f[B]BC_LONG_BIT\f[R], but is always at least twice as large as the integer type used to store digits. .SH LIMITS .PP The following are the limits on bc(1): .TP \f[B]BC_LONG_BIT\f[R] The number of bits in the \f[B]long\f[R] type in the environment where bc(1) was built. This determines how many decimal digits can be stored in a single large integer (see the \f[B]PERFORMANCE\f[R] section). .TP \f[B]BC_BASE_DIGS\f[R] The number of decimal digits per large integer (see the \f[B]PERFORMANCE\f[R] section). Depends on \f[B]BC_LONG_BIT\f[R]. .TP \f[B]BC_BASE_POW\f[R] The max decimal number that each large integer can store (see \f[B]BC_BASE_DIGS\f[R]) plus \f[B]1\f[R]. Depends on \f[B]BC_BASE_DIGS\f[R]. .TP \f[B]BC_OVERFLOW_MAX\f[R] The max number that the overflow type (see the \f[B]PERFORMANCE\f[R] section) can hold. Depends on \f[B]BC_LONG_BIT\f[R]. .TP \f[B]BC_BASE_MAX\f[R] The maximum output base. Set at \f[B]BC_BASE_POW\f[R]. .TP \f[B]BC_DIM_MAX\f[R] The maximum size of arrays. Set at \f[B]SIZE_MAX-1\f[R]. .TP \f[B]BC_SCALE_MAX\f[R] The maximum \f[B]scale\f[R]. Set at \f[B]BC_OVERFLOW_MAX-1\f[R]. .TP \f[B]BC_STRING_MAX\f[R] The maximum length of strings. Set at \f[B]BC_OVERFLOW_MAX-1\f[R]. .TP \f[B]BC_NAME_MAX\f[R] The maximum length of identifiers. Set at \f[B]BC_OVERFLOW_MAX-1\f[R]. .TP \f[B]BC_NUM_MAX\f[R] The maximum length of a number (in decimal digits), which includes digits after the decimal point. Set at \f[B]BC_OVERFLOW_MAX-1\f[R]. .TP Exponent The maximum allowable exponent (positive or negative). Set at \f[B]BC_OVERFLOW_MAX\f[R]. .TP Number of vars The maximum number of vars/arrays. Set at \f[B]SIZE_MAX-1\f[R]. .PP The actual values can be queried with the \f[B]limits\f[R] statement. .PP These limits are meant to be effectively non-existent; the limits are so large (at least on 64-bit machines) that there should not be any point at which they become a problem. In fact, memory should be exhausted before these limits should be hit. .SH ENVIRONMENT VARIABLES .PP bc(1) recognizes the following environment variables: .TP \f[B]POSIXLY_CORRECT\f[R] If this variable exists (no matter the contents), bc(1) behaves as if the \f[B]-s\f[R] option was given. .TP \f[B]BC_ENV_ARGS\f[R] This is another way to give command-line arguments to bc(1). They should be in the same format as all other command-line arguments. These are always processed first, so any files given in \f[B]BC_ENV_ARGS\f[R] will be processed before arguments and files given on the command-line. This gives the user the ability to set up \[lq]standard\[rq] options and files to be used at every invocation. The most useful thing for such files to contain would be useful functions that the user might want every time bc(1) runs. .RS .PP The code that parses \f[B]BC_ENV_ARGS\f[R] will correctly handle quoted arguments, but it does not understand escape sequences. For example, the string \f[B]\[lq]/home/gavin/some bc file.bc\[rq]\f[R] will be correctly parsed, but the string \f[B]\[lq]/home/gavin/some \[dq]bc\[dq] file.bc\[rq]\f[R] will include the backslashes. .PP The quote parsing will handle either kind of quotes, \f[B]\[cq]\f[R] or \f[B]\[lq]\f[R]. Thus, if you have a file with any number of single quotes in the name, you can use double quotes as the outside quotes, as in \f[B]\[lq]some `bc' file.bc\[rq]\f[R], and vice versa if you have a file with double quotes. However, handling a file with both kinds of quotes in \f[B]BC_ENV_ARGS\f[R] is not supported due to the complexity of the parsing, though such files are still supported on the command-line where the parsing is done by the shell. .RE .TP \f[B]BC_LINE_LENGTH\f[R] If this environment variable exists and contains an integer that is greater than \f[B]1\f[R] and is less than \f[B]UINT16_MAX\f[R] (\f[B]2\[ha]16-1\f[R]), bc(1) will output lines to that length, including the backslash (\f[B]\[rs]\f[R]). The default line length is \f[B]70\f[R]. .RS .PP The special value of \f[B]0\f[R] will disable line length checking and print numbers without regard to line length and without backslashes and newlines. .RE .TP \f[B]BC_BANNER\f[R] If this environment variable exists and contains an integer, then a non-zero value activates the copyright banner when bc(1) is in interactive mode, while zero deactivates it. .RS .PP If bc(1) is not in interactive mode (see the \f[B]INTERACTIVE MODE\f[R] section), then this environment variable has no effect because bc(1) does not print the banner when not in interactive mode. .PP This environment variable overrides the default, which can be queried with the \f[B]-h\f[R] or \f[B]--help\f[R] options. .RE .TP \f[B]BC_SIGINT_RESET\f[R] If bc(1) is not in interactive mode (see the \f[B]INTERACTIVE MODE\f[R] section), then this environment variable has no effect because bc(1) exits on \f[B]SIGINT\f[R] when not in interactive mode. .RS .PP However, when bc(1) is in interactive mode, then if this environment variable exists and contains an integer, a non-zero value makes bc(1) reset on \f[B]SIGINT\f[R], rather than exit, and zero makes bc(1) exit. If this environment variable exists and is \f[I]not\f[R] an integer, then bc(1) will exit on \f[B]SIGINT\f[R]. .PP This environment variable overrides the default, which can be queried with the \f[B]-h\f[R] or \f[B]--help\f[R] options. .RE .TP \f[B]BC_TTY_MODE\f[R] If TTY mode is \f[I]not\f[R] available (see the \f[B]TTY MODE\f[R] section), then this environment variable has no effect. .RS .PP However, when TTY mode is available, then if this environment variable exists and contains an integer, then a non-zero value makes bc(1) use TTY mode, and zero makes bc(1) not use TTY mode. .PP This environment variable overrides the default, which can be queried with the \f[B]-h\f[R] or \f[B]--help\f[R] options. .RE .TP \f[B]BC_PROMPT\f[R] If TTY mode is \f[I]not\f[R] available (see the \f[B]TTY MODE\f[R] section), then this environment variable has no effect. .RS .PP However, when TTY mode is available, then if this environment variable exists and contains an integer, a non-zero value makes bc(1) use a prompt, and zero or a non-integer makes bc(1) not use a prompt. If this environment variable does not exist and \f[B]BC_TTY_MODE\f[R] does, then the value of the \f[B]BC_TTY_MODE\f[R] environment variable is used. .PP This environment variable and the \f[B]BC_TTY_MODE\f[R] environment variable override the default, which can be queried with the \f[B]-h\f[R] or \f[B]--help\f[R] options. .RE +.TP +\f[B]BC_EXPR_EXIT\f[R] +If any expressions or expression files are given on the command-line +with \f[B]-e\f[R], \f[B]--expression\f[R], \f[B]-f\f[R], or +\f[B]--file\f[R], then if this environment variable exists and contains +an integer, a non-zero value makes bc(1) exit after executing the +expressions and expression files, and a non-zero value makes bc(1) not +exit. +.RS +.PP +This environment variable overrides the default, which can be queried +with the \f[B]-h\f[R] or \f[B]--help\f[R] options. +.RE .SH EXIT STATUS .PP bc(1) returns the following exit statuses: .TP \f[B]0\f[R] No error. .TP \f[B]1\f[R] A math error occurred. This follows standard practice of using \f[B]1\f[R] for expected errors, since math errors will happen in the process of normal execution. .RS .PP Math errors include divide by \f[B]0\f[R], taking the square root of a negative number, attempting to convert a negative number to a hardware integer, overflow when converting a number to a hardware integer, overflow when calculating the size of a number, and attempting to use a non-integer where an integer is required. .PP Converting to a hardware integer happens for the second operand of the power (\f[B]\[ha]\f[R]) operator and the corresponding assignment operator. .RE .TP \f[B]2\f[R] A parse error occurred. .RS .PP Parse errors include unexpected \f[B]EOF\f[R], using an invalid character, failing to find the end of a string or comment, using a token where it is invalid, giving an invalid expression, giving an invalid print statement, giving an invalid function definition, attempting to assign to an expression that is not a named expression (see the \f[I]Named Expressions\f[R] subsection of the \f[B]SYNTAX\f[R] section), giving an invalid \f[B]auto\f[R] list, having a duplicate \f[B]auto\f[R]/function parameter, failing to find the end of a code block, attempting to return a value from a \f[B]void\f[R] function, attempting to use a variable as a reference, and using any extensions when the option \f[B]-s\f[R] or any equivalents were given. .RE .TP \f[B]3\f[R] A runtime error occurred. .RS .PP Runtime errors include assigning an invalid number to any global (\f[B]ibase\f[R], \f[B]obase\f[R], or \f[B]scale\f[R]), giving a bad expression to a \f[B]read()\f[R] call, calling \f[B]read()\f[R] inside of a \f[B]read()\f[R] call, type errors, passing the wrong number of arguments to functions, attempting to call an undefined function, and attempting to use a \f[B]void\f[R] function call as a value in an expression. .RE .TP \f[B]4\f[R] A fatal error occurred. .RS .PP Fatal errors include memory allocation errors, I/O errors, failing to open files, attempting to use files that do not have only ASCII characters (bc(1) only accepts ASCII characters), attempting to open a directory as a file, and giving invalid command-line options. .RE .PP The exit status \f[B]4\f[R] is special; when a fatal error occurs, bc(1) always exits and returns \f[B]4\f[R], no matter what mode bc(1) is in. .PP The other statuses will only be returned when bc(1) is not in interactive mode (see the \f[B]INTERACTIVE MODE\f[R] section), since bc(1) resets its state (see the \f[B]RESET\f[R] section) and accepts more input when one of those errors occurs in interactive mode. This is also the case when interactive mode is forced by the \f[B]-i\f[R] flag or \f[B]--interactive\f[R] option. .PP These exit statuses allow bc(1) to be used in shell scripting with error checking, and its normal behavior can be forced by using the \f[B]-i\f[R] flag or \f[B]--interactive\f[R] option. .SH INTERACTIVE MODE .PP Per the standard (https://pubs.opengroup.org/onlinepubs/9699919799/utilities/bc.html), bc(1) has an interactive mode and a non-interactive mode. Interactive mode is turned on automatically when both \f[B]stdin\f[R] and \f[B]stdout\f[R] are hooked to a terminal, but the \f[B]-i\f[R] flag and \f[B]--interactive\f[R] option can turn it on in other situations. .PP In interactive mode, bc(1) attempts to recover from errors (see the \f[B]RESET\f[R] section), and in normal execution, flushes \f[B]stdout\f[R] as soon as execution is done for the current input. bc(1) may also reset on \f[B]SIGINT\f[R] instead of exit, depending on the contents of, or default for, the \f[B]BC_SIGINT_RESET\f[R] environment variable (see the \f[B]ENVIRONMENT VARIABLES\f[R] section). .SH TTY MODE .PP If \f[B]stdin\f[R], \f[B]stdout\f[R], and \f[B]stderr\f[R] are all connected to a TTY, then \[lq]TTY mode\[rq] is considered to be available, and thus, bc(1) can turn on TTY mode, subject to some settings. .PP If there is the environment variable \f[B]BC_TTY_MODE\f[R] in the environment (see the \f[B]ENVIRONMENT VARIABLES\f[R] section), then if that environment variable contains a non-zero integer, bc(1) will turn on TTY mode when \f[B]stdin\f[R], \f[B]stdout\f[R], and \f[B]stderr\f[R] are all connected to a TTY. If the \f[B]BC_TTY_MODE\f[R] environment variable exists but is \f[I]not\f[R] a non-zero integer, then bc(1) will not turn TTY mode on. .PP If the environment variable \f[B]BC_TTY_MODE\f[R] does \f[I]not\f[R] exist, the default setting is used. The default setting can be queried with the \f[B]-h\f[R] or \f[B]--help\f[R] options. .PP TTY mode is different from interactive mode because interactive mode is required in the bc(1) specification (https://pubs.opengroup.org/onlinepubs/9699919799/utilities/bc.html), and interactive mode requires only \f[B]stdin\f[R] and \f[B]stdout\f[R] to be connected to a terminal. .SS Command-Line History .PP Command-line history is only enabled if TTY mode is, i.e., that \f[B]stdin\f[R], \f[B]stdout\f[R], and \f[B]stderr\f[R] are connected to a TTY and the \f[B]BC_TTY_MODE\f[R] environment variable (see the \f[B]ENVIRONMENT VARIABLES\f[R] section) and its default do not disable TTY mode. See the \f[B]COMMAND LINE HISTORY\f[R] section for more information. .SS Prompt .PP If TTY mode is available, then a prompt can be enabled. Like TTY mode itself, it can be turned on or off with an environment variable: \f[B]BC_PROMPT\f[R] (see the \f[B]ENVIRONMENT VARIABLES\f[R] section). .PP If the environment variable \f[B]BC_PROMPT\f[R] exists and is a non-zero integer, then the prompt is turned on when \f[B]stdin\f[R], \f[B]stdout\f[R], and \f[B]stderr\f[R] are connected to a TTY and the \f[B]-P\f[R] and \f[B]--no-prompt\f[R] options were not used. The read prompt will be turned on under the same conditions, except that the \f[B]-R\f[R] and \f[B]--no-read-prompt\f[R] options must also not be used. .PP However, if \f[B]BC_PROMPT\f[R] does not exist, the prompt can be enabled or disabled with the \f[B]BC_TTY_MODE\f[R] environment variable, the \f[B]-P\f[R] and \f[B]--no-prompt\f[R] options, and the \f[B]-R\f[R] and \f[B]--no-read-prompt\f[R] options. See the \f[B]ENVIRONMENT VARIABLES\f[R] and \f[B]OPTIONS\f[R] sections for more details. .SH SIGNAL HANDLING .PP Sending a \f[B]SIGINT\f[R] will cause bc(1) to do one of two things. .PP If bc(1) is not in interactive mode (see the \f[B]INTERACTIVE MODE\f[R] section), or the \f[B]BC_SIGINT_RESET\f[R] environment variable (see the \f[B]ENVIRONMENT VARIABLES\f[R] section), or its default, is either not an integer or it is zero, bc(1) will exit. .PP However, if bc(1) is in interactive mode, and the \f[B]BC_SIGINT_RESET\f[R] or its default is an integer and non-zero, then bc(1) will stop executing the current input and reset (see the \f[B]RESET\f[R] section) upon receiving a \f[B]SIGINT\f[R]. .PP Note that \[lq]current input\[rq] can mean one of two things. If bc(1) is processing input from \f[B]stdin\f[R] in interactive mode, it will ask for more input. If bc(1) is processing input from a file in interactive mode, it will stop processing the file and start processing the next file, if one exists, or ask for input from \f[B]stdin\f[R] if no other file exists. .PP This means that if a \f[B]SIGINT\f[R] is sent to bc(1) as it is executing a file, it can seem as though bc(1) did not respond to the signal since it will immediately start executing the next file. This is by design; most files that users execute when interacting with bc(1) have function definitions, which are quick to parse. If a file takes a long time to execute, there may be a bug in that file. The rest of the files could still be executed without problem, allowing the user to continue. .PP \f[B]SIGTERM\f[R] and \f[B]SIGQUIT\f[R] cause bc(1) to clean up and exit, and it uses the default handler for all other signals. The one exception is \f[B]SIGHUP\f[R]; in that case, and only when bc(1) is in TTY mode (see the \f[B]TTY MODE\f[R] section), a \f[B]SIGHUP\f[R] will cause bc(1) to clean up and exit. .SH COMMAND LINE HISTORY .PP bc(1) supports interactive command-line editing. .PP If bc(1) can be in TTY mode (see the \f[B]TTY MODE\f[R] section), history can be enabled. This means that command-line history can only be enabled when \f[B]stdin\f[R], \f[B]stdout\f[R], and \f[B]stderr\f[R] are all connected to a TTY. .PP Like TTY mode itself, it can be turned on or off with the environment variable \f[B]BC_TTY_MODE\f[R] (see the \f[B]ENVIRONMENT VARIABLES\f[R] section). .PP If history is enabled, previous lines can be recalled and edited with the arrow keys. .PP \f[B]Note\f[R]: tabs are converted to 8 spaces. .SH LOCALES .PP This bc(1) ships with support for adding error messages for different locales and thus, supports \f[B]LC_MESSAGES\f[R]. .SH SEE ALSO .PP dc(1) .SH STANDARDS .PP bc(1) is compliant with the IEEE Std 1003.1-2017 (\[lq]POSIX.1-2017\[rq]) (https://pubs.opengroup.org/onlinepubs/9699919799/utilities/bc.html) specification. The flags \f[B]-efghiqsvVw\f[R], all long options, and the extensions noted above are extensions to that specification. .PP Note that the specification explicitly says that bc(1) only accepts numbers that use a period (\f[B].\f[R]) as a radix point, regardless of the value of \f[B]LC_NUMERIC\f[R]. .PP This bc(1) supports error messages for different locales, and thus, it supports \f[B]LC_MESSAGES\f[R]. .SH BUGS .PP None are known. Report bugs at https://git.yzena.com/gavin/bc. .SH AUTHORS .PP Gavin D. Howard and contributors. diff --git a/contrib/bc/manuals/bc/E.1.md b/contrib/bc/manuals/bc/E.1.md index 63367e436cc8..ba6e44c248c2 100644 --- a/contrib/bc/manuals/bc/E.1.md +++ b/contrib/bc/manuals/bc/E.1.md @@ -1,1365 +1,1376 @@ # NAME bc - arbitrary-precision decimal arithmetic language and calculator # SYNOPSIS **bc** [**-ghilPqRsvVw**] [**-\-global-stacks**] [**-\-help**] [**-\-interactive**] [**-\-mathlib**] [**-\-no-prompt**] [**-\-no-read-prompt**] [**-\-quiet**] [**-\-standard**] [**-\-warn**] [**-\-version**] [**-e** *expr*] [**-\-expression**=*expr*...] [**-f** *file*...] [**-\-file**=*file*...] [*file*...] # DESCRIPTION bc(1) is an interactive processor for a language first standardized in 1991 by POSIX. (The current standard is [here][1].) The language provides unlimited precision decimal arithmetic and is somewhat C-like, but there are differences. Such differences will be noted in this document. After parsing and handling options, this bc(1) reads any files given on the command line and executes them before reading from **stdin**. This bc(1) is a drop-in replacement for *any* bc(1), including (and especially) the GNU bc(1). **Note**: If running this bc(1) on *any* script meant for another bc(1) gives a parse error, it is probably because a word this bc(1) reserves as a keyword is used as the name of a function, variable, or array. To fix that, use the command-line option **-r** *keyword*, where *keyword* is the keyword that is used as a name in the script. For more information, see the **OPTIONS** section. If parsing scripts meant for other bc(1) implementations still does not work, that is a bug and should be reported. See the **BUGS** section. # OPTIONS The following are the options that bc(1) accepts. **-g**, **-\-global-stacks** : Turns the globals **ibase**, **obase**, and **scale** into stacks. This has the effect that a copy of the current value of all three are pushed onto a stack for every function call, as well as popped when every function returns. This means that functions can assign to any and all of those globals without worrying that the change will affect other functions. Thus, a hypothetical function named **output(x,b)** that simply printed **x** in base **b** could be written like this: define void output(x, b) { obase=b x } instead of like this: define void output(x, b) { auto c c=obase obase=b x obase=c } This makes writing functions much easier. However, since using this flag means that functions cannot set **ibase**, **obase**, or **scale** globally, functions that are made to do so cannot work anymore. There are two possible use cases for that, and each has a solution. First, if a function is called on startup to turn bc(1) into a number converter, it is possible to replace that capability with various shell aliases. Examples: alias d2o="bc -e ibase=A -e obase=8" alias h2b="bc -e ibase=G -e obase=2" Second, if the purpose of a function is to set **ibase**, **obase**, or **scale** globally for any other purpose, it could be split into one to three functions (based on how many globals it sets) and each of those functions could return the desired value for a global. If the behavior of this option is desired for every run of bc(1), then users could make sure to define **BC_ENV_ARGS** and include this option (see the **ENVIRONMENT VARIABLES** section for more details). If **-s**, **-w**, or any equivalents are used, this option is ignored. This is a **non-portable extension**. **-h**, **-\-help** : Prints a usage message and quits. **-i**, **-\-interactive** : Forces interactive mode. (See the **INTERACTIVE MODE** section.) This is a **non-portable extension**. **-L**, **-\-no-line-length** : Disables line length checking and prints numbers without backslashes and newlines. In other words, this option sets **BC_LINE_LENGTH** to **0** (see the **ENVIRONMENT VARIABLES** section). This is a **non-portable extension**. **-l**, **-\-mathlib** : Sets **scale** (see the **SYNTAX** section) to **20** and loads the included math library before running any code, including any expressions or files specified on the command line. To learn what is in the library, see the **LIBRARY** section. **-P**, **-\-no-prompt** : Disables the prompt in TTY mode. (The prompt is only enabled in TTY mode. See the **TTY MODE** section.) This is mostly for those users that do not want a prompt or are not used to having them in bc(1). Most of those users would want to put this option in **BC_ENV_ARGS** (see the **ENVIRONMENT VARIABLES** section). These options override the **BC_PROMPT** and **BC_TTY_MODE** environment variables (see the **ENVIRONMENT VARIABLES** section). This is a **non-portable extension**. **-R**, **-\-no-read-prompt** : Disables the read prompt in TTY mode. (The read prompt is only enabled in TTY mode. See the **TTY MODE** section.) This is mostly for those users that do not want a read prompt or are not used to having them in bc(1). Most of those users would want to put this option in **BC_ENV_ARGS** (see the **ENVIRONMENT VARIABLES** section). This option is also useful in hash bang lines of bc(1) scripts that prompt for user input. This option does not disable the regular prompt because the read prompt is only used when the **read()** built-in function is called. These options *do* override the **BC_PROMPT** and **BC_TTY_MODE** environment variables (see the **ENVIRONMENT VARIABLES** section), but only for the read prompt. This is a **non-portable extension**. **-r** *keyword*, **-\-redefine**=*keyword* : Redefines *keyword* in order to allow it to be used as a function, variable, or array name. This is useful when this bc(1) gives parse errors when parsing scripts meant for other bc(1) implementations. The keywords this bc(1) allows to be redefined are: * **abs** * **asciify** * **continue** * **divmod** * **else** * **halt** * **last** * **limits** * **maxibase** * **maxobase** * **maxscale** * **modexp** * **print** * **read** * **stream** If any of those keywords are used as a function, variable, or array name in a script, use this option with the keyword as the argument. If multiple are used, use this option for all of them; it can be used multiple times. Keywords are *not* redefined when parsing the builtin math library (see the **LIBRARY** section). It is a fatal error to redefine keywords mandated by the POSIX standard. It is a fatal error to attempt to redefine words that this bc(1) does not reserve as keywords. **-q**, **-\-quiet** : This option is for compatibility with the [GNU bc(1)][2]; it is a no-op. Without this option, GNU bc(1) prints a copyright header. This bc(1) only prints the copyright header if one or more of the **-v**, **-V**, or **-\-version** options are given. This is a **non-portable extension**. **-s**, **-\-standard** : Process exactly the language defined by the [standard][1] and error if any extensions are used. This is a **non-portable extension**. **-v**, **-V**, **-\-version** : Print the version information (copyright header) and exit. This is a **non-portable extension**. **-w**, **-\-warn** : Like **-s** and **-\-standard**, except that warnings (and not errors) are printed for non-standard extensions and execution continues normally. This is a **non-portable extension**. **-z**, **-\-leading-zeroes** : Makes bc(1) print all numbers greater than **-1** and less than **1**, and not equal to **0**, with a leading zero. This can be set for individual numbers with the **plz(x)**, plznl(x)**, **pnlz(x)**, and **pnlznl(x)** functions in the extended math library (see the **LIBRARY** section). This is a **non-portable extension**. **-e** *expr*, **-\-expression**=*expr* : Evaluates *expr*. If multiple expressions are given, they are evaluated in order. If files are given as well (see below), the expressions and files are evaluated in the order given. This means that if a file is given before an expression, the file is read in and evaluated first. If this option is given on the command-line (i.e., not in **BC_ENV_ARGS**, see the **ENVIRONMENT VARIABLES** section), then after processing all expressions and files, bc(1) will exit, unless **-** (**stdin**) was given as an argument at least once to **-f** or **-\-file**, whether on the command-line or in **BC_ENV_ARGS**. However, if any other **-e**, **-\-expression**, **-f**, or **-\-file** arguments are given after **-f-** or equivalent is given, bc(1) will give a fatal error and exit. This is a **non-portable extension**. **-f** *file*, **-\-file**=*file* : Reads in *file* and evaluates it, line by line, as though it were read through **stdin**. If expressions are also given (see above), the expressions are evaluated in the order given. If this option is given on the command-line (i.e., not in **BC_ENV_ARGS**, see the **ENVIRONMENT VARIABLES** section), then after processing all expressions and files, bc(1) will exit, unless **-** (**stdin**) was given as an argument at least once to **-f** or **-\-file**. However, if any other **-e**, **-\-expression**, **-f**, or **-\-file** arguments are given after **-f-** or equivalent is given, bc(1) will give a fatal error and exit. This is a **non-portable extension**. All long options are **non-portable extensions**. # STDIN If no files or expressions are given by the **-f**, **-\-file**, **-e**, or **-\-expression** options, then bc(1) read from **stdin**. However, there are a few caveats to this. First, **stdin** is evaluated a line at a time. The only exception to this is if the parse cannot complete. That means that starting a string without ending it or starting a function, **if** statement, or loop without ending it will also cause bc(1) to not execute. Second, after an **if** statement, bc(1) doesn't know if an **else** statement will follow, so it will not execute until it knows there will not be an **else** statement. # STDOUT Any non-error output is written to **stdout**. In addition, if history (see the **HISTORY** section) and the prompt (see the **TTY MODE** section) are enabled, both are output to **stdout**. **Note**: Unlike other bc(1) implementations, this bc(1) will issue a fatal error (see the **EXIT STATUS** section) if it cannot write to **stdout**, so if **stdout** is closed, as in **bc >&-**, it will quit with an error. This is done so that bc(1) can report problems when **stdout** is redirected to a file. If there are scripts that depend on the behavior of other bc(1) implementations, it is recommended that those scripts be changed to redirect **stdout** to **/dev/null**. # STDERR Any error output is written to **stderr**. **Note**: Unlike other bc(1) implementations, this bc(1) will issue a fatal error (see the **EXIT STATUS** section) if it cannot write to **stderr**, so if **stderr** is closed, as in **bc 2>&-**, it will quit with an error. This is done so that bc(1) can exit with an error code when **stderr** is redirected to a file. If there are scripts that depend on the behavior of other bc(1) implementations, it is recommended that those scripts be changed to redirect **stderr** to **/dev/null**. # SYNTAX The syntax for bc(1) programs is mostly C-like, with some differences. This bc(1) follows the [POSIX standard][1], which is a much more thorough resource for the language this bc(1) accepts. This section is meant to be a summary and a listing of all the extensions to the standard. In the sections below, **E** means expression, **S** means statement, and **I** means identifier. Identifiers (**I**) start with a lowercase letter and can be followed by any number (up to **BC_NAME_MAX-1**) of lowercase letters (**a-z**), digits (**0-9**), and underscores (**\_**). The regex is **\[a-z\]\[a-z0-9\_\]\***. Identifiers with more than one character (letter) are a **non-portable extension**. **ibase** is a global variable determining how to interpret constant numbers. It is the "input" base, or the number base used for interpreting input numbers. **ibase** is initially **10**. If the **-s** (**-\-standard**) and **-w** (**-\-warn**) flags were not given on the command line, the max allowable value for **ibase** is **36**. Otherwise, it is **16**. The min allowable value for **ibase** is **2**. The max allowable value for **ibase** can be queried in bc(1) programs with the **maxibase()** built-in function. **obase** is a global variable determining how to output results. It is the "output" base, or the number base used for outputting numbers. **obase** is initially **10**. The max allowable value for **obase** is **BC_BASE_MAX** and can be queried in bc(1) programs with the **maxobase()** built-in function. The min allowable value for **obase** is **2**. Values are output in the specified base. The *scale* of an expression is the number of digits in the result of the expression right of the decimal point, and **scale** is a global variable that sets the precision of any operations, with exceptions. **scale** is initially **0**. **scale** cannot be negative. The max allowable value for **scale** is **BC_SCALE_MAX** and can be queried in bc(1) programs with the **maxscale()** built-in function. bc(1) has both *global* variables and *local* variables. All *local* variables are local to the function; they are parameters or are introduced in the **auto** list of a function (see the **FUNCTIONS** section). If a variable is accessed which is not a parameter or in the **auto** list, it is assumed to be *global*. If a parent function has a *local* variable version of a variable that a child function considers *global*, the value of that *global* variable in the child function is the value of the variable in the parent function, not the value of the actual *global* variable. All of the above applies to arrays as well. The value of a statement that is an expression (i.e., any of the named expressions or operands) is printed unless the lowest precedence operator is an assignment operator *and* the expression is notsurrounded by parentheses. The value that is printed is also assigned to the special variable **last**. A single dot (**.**) may also be used as a synonym for **last**. These are **non-portable extensions**. Either semicolons or newlines may separate statements. ## Comments There are two kinds of comments: 1. Block comments are enclosed in **/\*** and **\*/**. 2. Line comments go from **#** until, and not including, the next newline. This is a **non-portable extension**. ## Named Expressions The following are named expressions in bc(1): 1. Variables: **I** 2. Array Elements: **I[E]** 3. **ibase** 4. **obase** 5. **scale** 6. **last** or a single dot (**.**) Number 6 is a **non-portable extension**. Variables and arrays do not interfere; users can have arrays named the same as variables. This also applies to functions (see the **FUNCTIONS** section), so a user can have a variable, array, and function that all have the same name, and they will not shadow each other, whether inside of functions or not. Named expressions are required as the operand of **increment**/**decrement** operators and as the left side of **assignment** operators (see the *Operators* subsection). ## Operands The following are valid operands in bc(1): 1. Numbers (see the *Numbers* subsection below). 2. Array indices (**I[E]**). 3. **(E)**: The value of **E** (used to change precedence). 4. **sqrt(E)**: The square root of **E**. **E** must be non-negative. 5. **length(E)**: The number of significant decimal digits in **E**. Returns **1** for **0** with no decimal places. If given a string, the length of the string is returned. Passing a string to **length(E)** is a **non-portable extension**. 6. **length(I[])**: The number of elements in the array **I**. This is a **non-portable extension**. 7. **scale(E)**: The *scale* of **E**. 8. **abs(E)**: The absolute value of **E**. This is a **non-portable extension**. 9. **modexp(E, E, E)**: Modular exponentiation, where the first expression is the base, the second is the exponent, and the third is the modulus. All three values must be integers. The second argument must be non-negative. The third argument must be non-zero. This is a **non-portable extension**. 10. **divmod(E, E, I[])**: Division and modulus in one operation. This is for optimization. The first expression is the dividend, and the second is the divisor, which must be non-zero. The return value is the quotient, and the modulus is stored in index **0** of the provided array (the last argument). This is a **non-portable extension**. 11. **asciify(E)**: If **E** is a string, returns a string that is the first letter of its argument. If it is a number, calculates the number mod **256** and returns that number as a one-character string. This is a **non-portable extension**. 12. **I()**, **I(E)**, **I(E, E)**, and so on, where **I** is an identifier for a non-**void** function (see the *Void Functions* subsection of the **FUNCTIONS** section). The **E** argument(s) may also be arrays of the form **I[]**, which will automatically be turned into array references (see the *Array References* subsection of the **FUNCTIONS** section) if the corresponding parameter in the function definition is an array reference. 13. **read()**: Reads a line from **stdin** and uses that as an expression. The result of that expression is the result of the **read()** operand. This is a **non-portable extension**. 14. **maxibase()**: The max allowable **ibase**. This is a **non-portable extension**. 15. **maxobase()**: The max allowable **obase**. This is a **non-portable extension**. 16. **maxscale()**: The max allowable **scale**. This is a **non-portable extension**. 17. **line_length()**: The line length set with **BC_LINE_LENGTH** (see the **ENVIRONMENT VARIABLES** section). This is a **non-portable extension**. 18. **global_stacks()**: **0** if global stacks are not enabled with the **-g** or **-\-global-stacks** options, non-zero otherwise. See the **OPTIONS** section. This is a **non-portable extension**. 19. **leading_zero()**: **0** if leading zeroes are not enabled with the **-z** or **--leading-zeroes** options, non-zero otherwise. See the **OPTIONS** section. This is a **non-portable extension**. ## Numbers Numbers are strings made up of digits, uppercase letters, and at most **1** period for a radix. Numbers can have up to **BC_NUM_MAX** digits. Uppercase letters are equal to **9** + their position in the alphabet (i.e., **A** equals **10**, or **9+1**). If a digit or letter makes no sense with the current value of **ibase**, they are set to the value of the highest valid digit in **ibase**. Single-character numbers (i.e., **A** alone) take the value that they would have if they were valid digits, regardless of the value of **ibase**. This means that **A** alone always equals decimal **10** and **Z** alone always equals decimal **35**. ## Operators The following arithmetic and logical operators can be used. They are listed in order of decreasing precedence. Operators in the same group have the same precedence. **++** **-\-** : Type: Prefix and Postfix Associativity: None Description: **increment**, **decrement** **-** **!** : Type: Prefix Associativity: None Description: **negation**, **boolean not** **\^** : Type: Binary Associativity: Right Description: **power** **\*** **/** **%** : Type: Binary Associativity: Left Description: **multiply**, **divide**, **modulus** **+** **-** : Type: Binary Associativity: Left Description: **add**, **subtract** **=** **+=** **-=** **\*=** **/=** **%=** **\^=** : Type: Binary Associativity: Right Description: **assignment** **==** **\<=** **\>=** **!=** **\<** **\>** : Type: Binary Associativity: Left Description: **relational** **&&** : Type: Binary Associativity: Left Description: **boolean and** **||** : Type: Binary Associativity: Left Description: **boolean or** The operators will be described in more detail below. **++** **-\-** : The prefix and postfix **increment** and **decrement** operators behave exactly like they would in C. They require a named expression (see the *Named Expressions* subsection) as an operand. The prefix versions of these operators are more efficient; use them where possible. **-** : The **negation** operator returns **0** if a user attempts to negate any expression with the value **0**. Otherwise, a copy of the expression with its sign flipped is returned. **!** : The **boolean not** operator returns **1** if the expression is **0**, or **0** otherwise. This is a **non-portable extension**. **\^** : The **power** operator (not the **exclusive or** operator, as it would be in C) takes two expressions and raises the first to the power of the value of the second. The *scale* of the result is equal to **scale**. The second expression must be an integer (no *scale*), and if it is negative, the first value must be non-zero. **\*** : The **multiply** operator takes two expressions, multiplies them, and returns the product. If **a** is the *scale* of the first expression and **b** is the *scale* of the second expression, the *scale* of the result is equal to **min(a+b,max(scale,a,b))** where **min()** and **max()** return the obvious values. **/** : The **divide** operator takes two expressions, divides them, and returns the quotient. The *scale* of the result shall be the value of **scale**. The second expression must be non-zero. **%** : The **modulus** operator takes two expressions, **a** and **b**, and evaluates them by 1) Computing **a/b** to current **scale** and 2) Using the result of step 1 to calculate **a-(a/b)\*b** to *scale* **max(scale+scale(b),scale(a))**. The second expression must be non-zero. **+** : The **add** operator takes two expressions, **a** and **b**, and returns the sum, with a *scale* equal to the max of the *scale*s of **a** and **b**. **-** : The **subtract** operator takes two expressions, **a** and **b**, and returns the difference, with a *scale* equal to the max of the *scale*s of **a** and **b**. **=** **+=** **-=** **\*=** **/=** **%=** **\^=** : The **assignment** operators take two expressions, **a** and **b** where **a** is a named expression (see the *Named Expressions* subsection). For **=**, **b** is copied and the result is assigned to **a**. For all others, **a** and **b** are applied as operands to the corresponding arithmetic operator and the result is assigned to **a**. **==** **\<=** **\>=** **!=** **\<** **\>** : The **relational** operators compare two expressions, **a** and **b**, and if the relation holds, according to C language semantics, the result is **1**. Otherwise, it is **0**. Note that unlike in C, these operators have a lower precedence than the **assignment** operators, which means that **a=b\>c** is interpreted as **(a=b)\>c**. Also, unlike the [standard][1] requires, these operators can appear anywhere any other expressions can be used. This allowance is a **non-portable extension**. **&&** : The **boolean and** operator takes two expressions and returns **1** if both expressions are non-zero, **0** otherwise. This is *not* a short-circuit operator. This is a **non-portable extension**. **||** : The **boolean or** operator takes two expressions and returns **1** if one of the expressions is non-zero, **0** otherwise. This is *not* a short-circuit operator. This is a **non-portable extension**. ## Statements The following items are statements: 1. **E** 2. **{** **S** **;** ... **;** **S** **}** 3. **if** **(** **E** **)** **S** 4. **if** **(** **E** **)** **S** **else** **S** 5. **while** **(** **E** **)** **S** 6. **for** **(** **E** **;** **E** **;** **E** **)** **S** 7. An empty statement 8. **break** 9. **continue** 10. **quit** 11. **halt** 12. **limits** 13. A string of characters, enclosed in double quotes 14. **print** **E** **,** ... **,** **E** 15. **stream** **E** **,** ... **,** **E** 16. **I()**, **I(E)**, **I(E, E)**, and so on, where **I** is an identifier for a **void** function (see the *Void Functions* subsection of the **FUNCTIONS** section). The **E** argument(s) may also be arrays of the form **I[]**, which will automatically be turned into array references (see the *Array References* subsection of the **FUNCTIONS** section) if the corresponding parameter in the function definition is an array reference. Numbers 4, 9, 11, 12, 14, 15, and 16 are **non-portable extensions**. Also, as a **non-portable extension**, any or all of the expressions in the header of a for loop may be omitted. If the condition (second expression) is omitted, it is assumed to be a constant **1**. The **break** statement causes a loop to stop iterating and resume execution immediately following a loop. This is only allowed in loops. The **continue** statement causes a loop iteration to stop early and returns to the start of the loop, including testing the loop condition. This is only allowed in loops. The **if** **else** statement does the same thing as in C. The **quit** statement causes bc(1) to quit, even if it is on a branch that will not be executed (it is a compile-time command). The **halt** statement causes bc(1) to quit, if it is executed. (Unlike **quit** if it is on a branch of an **if** statement that is not executed, bc(1) does not quit.) The **limits** statement prints the limits that this bc(1) is subject to. This is like the **quit** statement in that it is a compile-time command. An expression by itself is evaluated and printed, followed by a newline. ## Strings If strings appear as a statement by themselves, they are printed without a trailing newline. In addition to appearing as a lone statement by themselves, strings can be assigned to variables and array elements. They can also be passed to functions in variable parameters. If any statement that expects a string is given a variable that had a string assigned to it, the statement acts as though it had received a string. If any math operation is attempted on a string or a variable or array element that has been assigned a string, an error is raised, and bc(1) resets (see the **RESET** section). Assigning strings to variables and array elements and passing them to functions are **non-portable extensions**. ## Print Statement The "expressions" in a **print** statement may also be strings. If they are, there are backslash escape sequences that are interpreted specially. What those sequences are, and what they cause to be printed, are shown below: **\\a**: **\\a** **\\b**: **\\b** **\\\\**: **\\** **\\e**: **\\** **\\f**: **\\f** **\\n**: **\\n** **\\q**: **"** **\\r**: **\\r** **\\t**: **\\t** Any other character following a backslash causes the backslash and character to be printed as-is. Any non-string expression in a print statement shall be assigned to **last**, like any other expression that is printed. ## Stream Statement The "expressions in a **stream** statement may also be strings. If a **stream** statement is given a string, it prints the string as though the string had appeared as its own statement. In other words, the **stream** statement prints strings normally, without a newline. If a **stream** statement is given a number, a copy of it is truncated and its absolute value is calculated. The result is then printed as though **obase** is **256** and each digit is interpreted as an 8-bit ASCII character, making it a byte stream. ## Order of Evaluation All expressions in a statment are evaluated left to right, except as necessary to maintain order of operations. This means, for example, assuming that **i** is equal to **0**, in the expression a[i++] = i++ the first (or 0th) element of **a** is set to **1**, and **i** is equal to **2** at the end of the expression. This includes function arguments. Thus, assuming **i** is equal to **0**, this means that in the expression x(i++, i++) the first argument passed to **x()** is **0**, and the second argument is **1**, while **i** is equal to **2** before the function starts executing. # FUNCTIONS Function definitions are as follows: ``` define I(I,...,I){ auto I,...,I S;...;S return(E) } ``` Any **I** in the parameter list or **auto** list may be replaced with **I[]** to make a parameter or **auto** var an array, and any **I** in the parameter list may be replaced with **\*I[]** to make a parameter an array reference. Callers of functions that take array references should not put an asterisk in the call; they must be called with just **I[]** like normal array parameters and will be automatically converted into references. As a **non-portable extension**, the opening brace of a **define** statement may appear on the next line. As a **non-portable extension**, the return statement may also be in one of the following forms: 1. **return** 2. **return** **(** **)** 3. **return** **E** The first two, or not specifying a **return** statement, is equivalent to **return (0)**, unless the function is a **void** function (see the *Void Functions* subsection below). ## Void Functions Functions can also be **void** functions, defined as follows: ``` define void I(I,...,I){ auto I,...,I S;...;S return } ``` They can only be used as standalone expressions, where such an expression would be printed alone, except in a print statement. Void functions can only use the first two **return** statements listed above. They can also omit the return statement entirely. The word "void" is not treated as a keyword; it is still possible to have variables, arrays, and functions named **void**. The word "void" is only treated specially right after the **define** keyword. This is a **non-portable extension**. ## Array References For any array in the parameter list, if the array is declared in the form ``` *I[] ``` it is a **reference**. Any changes to the array in the function are reflected, when the function returns, to the array that was passed in. Other than this, all function arguments are passed by value. This is a **non-portable extension**. # LIBRARY All of the functions below are available when the **-l** or **-\-mathlib** command-line flags are given. ## Standard Library The [standard][1] defines the following functions for the math library: **s(x)** : Returns the sine of **x**, which is assumed to be in radians. This is a transcendental function (see the *Transcendental Functions* subsection below). **c(x)** : Returns the cosine of **x**, which is assumed to be in radians. This is a transcendental function (see the *Transcendental Functions* subsection below). **a(x)** : Returns the arctangent of **x**, in radians. This is a transcendental function (see the *Transcendental Functions* subsection below). **l(x)** : Returns the natural logarithm of **x**. This is a transcendental function (see the *Transcendental Functions* subsection below). **e(x)** : Returns the mathematical constant **e** raised to the power of **x**. This is a transcendental function (see the *Transcendental Functions* subsection below). **j(x, n)** : Returns the bessel integer order **n** (truncated) of **x**. This is a transcendental function (see the *Transcendental Functions* subsection below). ## Transcendental Functions All transcendental functions can return slightly inaccurate results (up to 1 [ULP][4]). This is unavoidable, and [this article][5] explains why it is impossible and unnecessary to calculate exact results for the transcendental functions. Because of the possible inaccuracy, I recommend that users call those functions with the precision (**scale**) set to at least 1 higher than is necessary. If exact results are *absolutely* required, users can double the precision (**scale**) and then truncate. The transcendental functions in the standard math library are: * **s(x)** * **c(x)** * **a(x)** * **l(x)** * **e(x)** * **j(x, n)** # RESET When bc(1) encounters an error or a signal that it has a non-default handler for, it resets. This means that several things happen. First, any functions that are executing are stopped and popped off the stack. The behavior is not unlike that of exceptions in programming languages. Then the execution point is set so that any code waiting to execute (after all functions returned) is skipped. Thus, when bc(1) resets, it skips any remaining code waiting to be executed. Then, if it is interactive mode, and the error was not a fatal error (see the **EXIT STATUS** section), it asks for more input; otherwise, it exits with the appropriate return code. Note that this reset behavior is different from the GNU bc(1), which attempts to start executing the statement right after the one that caused an error. # PERFORMANCE Most bc(1) implementations use **char** types to calculate the value of **1** decimal digit at a time, but that can be slow. This bc(1) does something different. It uses large integers to calculate more than **1** decimal digit at a time. If built in a environment where **BC_LONG_BIT** (see the **LIMITS** section) is **64**, then each integer has **9** decimal digits. If built in an environment where **BC_LONG_BIT** is **32** then each integer has **4** decimal digits. This value (the number of decimal digits per large integer) is called **BC_BASE_DIGS**. The actual values of **BC_LONG_BIT** and **BC_BASE_DIGS** can be queried with the **limits** statement. In addition, this bc(1) uses an even larger integer for overflow checking. This integer type depends on the value of **BC_LONG_BIT**, but is always at least twice as large as the integer type used to store digits. # LIMITS The following are the limits on bc(1): **BC_LONG_BIT** : The number of bits in the **long** type in the environment where bc(1) was built. This determines how many decimal digits can be stored in a single large integer (see the **PERFORMANCE** section). **BC_BASE_DIGS** : The number of decimal digits per large integer (see the **PERFORMANCE** section). Depends on **BC_LONG_BIT**. **BC_BASE_POW** : The max decimal number that each large integer can store (see **BC_BASE_DIGS**) plus **1**. Depends on **BC_BASE_DIGS**. **BC_OVERFLOW_MAX** : The max number that the overflow type (see the **PERFORMANCE** section) can hold. Depends on **BC_LONG_BIT**. **BC_BASE_MAX** : The maximum output base. Set at **BC_BASE_POW**. **BC_DIM_MAX** : The maximum size of arrays. Set at **SIZE_MAX-1**. **BC_SCALE_MAX** : The maximum **scale**. Set at **BC_OVERFLOW_MAX-1**. **BC_STRING_MAX** : The maximum length of strings. Set at **BC_OVERFLOW_MAX-1**. **BC_NAME_MAX** : The maximum length of identifiers. Set at **BC_OVERFLOW_MAX-1**. **BC_NUM_MAX** : The maximum length of a number (in decimal digits), which includes digits after the decimal point. Set at **BC_OVERFLOW_MAX-1**. Exponent : The maximum allowable exponent (positive or negative). Set at **BC_OVERFLOW_MAX**. Number of vars : The maximum number of vars/arrays. Set at **SIZE_MAX-1**. The actual values can be queried with the **limits** statement. These limits are meant to be effectively non-existent; the limits are so large (at least on 64-bit machines) that there should not be any point at which they become a problem. In fact, memory should be exhausted before these limits should be hit. # ENVIRONMENT VARIABLES bc(1) recognizes the following environment variables: **POSIXLY_CORRECT** : If this variable exists (no matter the contents), bc(1) behaves as if the **-s** option was given. **BC_ENV_ARGS** : This is another way to give command-line arguments to bc(1). They should be in the same format as all other command-line arguments. These are always processed first, so any files given in **BC_ENV_ARGS** will be processed before arguments and files given on the command-line. This gives the user the ability to set up "standard" options and files to be used at every invocation. The most useful thing for such files to contain would be useful functions that the user might want every time bc(1) runs. The code that parses **BC_ENV_ARGS** will correctly handle quoted arguments, but it does not understand escape sequences. For example, the string **"/home/gavin/some bc file.bc"** will be correctly parsed, but the string **"/home/gavin/some \"bc\" file.bc"** will include the backslashes. The quote parsing will handle either kind of quotes, **'** or **"**. Thus, if you have a file with any number of single quotes in the name, you can use double quotes as the outside quotes, as in **"some 'bc' file.bc"**, and vice versa if you have a file with double quotes. However, handling a file with both kinds of quotes in **BC_ENV_ARGS** is not supported due to the complexity of the parsing, though such files are still supported on the command-line where the parsing is done by the shell. **BC_LINE_LENGTH** : If this environment variable exists and contains an integer that is greater than **1** and is less than **UINT16_MAX** (**2\^16-1**), bc(1) will output lines to that length, including the backslash (**\\**). The default line length is **70**. The special value of **0** will disable line length checking and print numbers without regard to line length and without backslashes and newlines. **BC_BANNER** : If this environment variable exists and contains an integer, then a non-zero value activates the copyright banner when bc(1) is in interactive mode, while zero deactivates it. If bc(1) is not in interactive mode (see the **INTERACTIVE MODE** section), then this environment variable has no effect because bc(1) does not print the banner when not in interactive mode. This environment variable overrides the default, which can be queried with the **-h** or **-\-help** options. **BC_SIGINT_RESET** : If bc(1) is not in interactive mode (see the **INTERACTIVE MODE** section), then this environment variable has no effect because bc(1) exits on **SIGINT** when not in interactive mode. However, when bc(1) is in interactive mode, then if this environment variable exists and contains an integer, a non-zero value makes bc(1) reset on **SIGINT**, rather than exit, and zero makes bc(1) exit. If this environment variable exists and is *not* an integer, then bc(1) will exit on **SIGINT**. This environment variable overrides the default, which can be queried with the **-h** or **-\-help** options. **BC_TTY_MODE** : If TTY mode is *not* available (see the **TTY MODE** section), then this environment variable has no effect. However, when TTY mode is available, then if this environment variable exists and contains an integer, then a non-zero value makes bc(1) use TTY mode, and zero makes bc(1) not use TTY mode. This environment variable overrides the default, which can be queried with the **-h** or **-\-help** options. **BC_PROMPT** : If TTY mode is *not* available (see the **TTY MODE** section), then this environment variable has no effect. However, when TTY mode is available, then if this environment variable exists and contains an integer, a non-zero value makes bc(1) use a prompt, and zero or a non-integer makes bc(1) not use a prompt. If this environment variable does not exist and **BC_TTY_MODE** does, then the value of the **BC_TTY_MODE** environment variable is used. This environment variable and the **BC_TTY_MODE** environment variable override the default, which can be queried with the **-h** or **-\-help** options. +**BC_EXPR_EXIT** + +: If any expressions or expression files are given on the command-line with + **-e**, **-\-expression**, **-f**, or **-\-file**, then if this environment + variable exists and contains an integer, a non-zero value makes bc(1) exit + after executing the expressions and expression files, and a non-zero value + makes bc(1) not exit. + + This environment variable overrides the default, which can be queried with + the **-h** or **-\-help** options. + # EXIT STATUS bc(1) returns the following exit statuses: **0** : No error. **1** : A math error occurred. This follows standard practice of using **1** for expected errors, since math errors will happen in the process of normal execution. Math errors include divide by **0**, taking the square root of a negative number, attempting to convert a negative number to a hardware integer, overflow when converting a number to a hardware integer, overflow when calculating the size of a number, and attempting to use a non-integer where an integer is required. Converting to a hardware integer happens for the second operand of the power (**\^**) operator and the corresponding assignment operator. **2** : A parse error occurred. Parse errors include unexpected **EOF**, using an invalid character, failing to find the end of a string or comment, using a token where it is invalid, giving an invalid expression, giving an invalid print statement, giving an invalid function definition, attempting to assign to an expression that is not a named expression (see the *Named Expressions* subsection of the **SYNTAX** section), giving an invalid **auto** list, having a duplicate **auto**/function parameter, failing to find the end of a code block, attempting to return a value from a **void** function, attempting to use a variable as a reference, and using any extensions when the option **-s** or any equivalents were given. **3** : A runtime error occurred. Runtime errors include assigning an invalid number to any global (**ibase**, **obase**, or **scale**), giving a bad expression to a **read()** call, calling **read()** inside of a **read()** call, type errors, passing the wrong number of arguments to functions, attempting to call an undefined function, and attempting to use a **void** function call as a value in an expression. **4** : A fatal error occurred. Fatal errors include memory allocation errors, I/O errors, failing to open files, attempting to use files that do not have only ASCII characters (bc(1) only accepts ASCII characters), attempting to open a directory as a file, and giving invalid command-line options. The exit status **4** is special; when a fatal error occurs, bc(1) always exits and returns **4**, no matter what mode bc(1) is in. The other statuses will only be returned when bc(1) is not in interactive mode (see the **INTERACTIVE MODE** section), since bc(1) resets its state (see the **RESET** section) and accepts more input when one of those errors occurs in interactive mode. This is also the case when interactive mode is forced by the **-i** flag or **-\-interactive** option. These exit statuses allow bc(1) to be used in shell scripting with error checking, and its normal behavior can be forced by using the **-i** flag or **-\-interactive** option. # INTERACTIVE MODE Per the [standard][1], bc(1) has an interactive mode and a non-interactive mode. Interactive mode is turned on automatically when both **stdin** and **stdout** are hooked to a terminal, but the **-i** flag and **-\-interactive** option can turn it on in other situations. In interactive mode, bc(1) attempts to recover from errors (see the **RESET** section), and in normal execution, flushes **stdout** as soon as execution is done for the current input. bc(1) may also reset on **SIGINT** instead of exit, depending on the contents of, or default for, the **BC_SIGINT_RESET** environment variable (see the **ENVIRONMENT VARIABLES** section). # TTY MODE If **stdin**, **stdout**, and **stderr** are all connected to a TTY, then "TTY mode" is considered to be available, and thus, bc(1) can turn on TTY mode, subject to some settings. If there is the environment variable **BC_TTY_MODE** in the environment (see the **ENVIRONMENT VARIABLES** section), then if that environment variable contains a non-zero integer, bc(1) will turn on TTY mode when **stdin**, **stdout**, and **stderr** are all connected to a TTY. If the **BC_TTY_MODE** environment variable exists but is *not* a non-zero integer, then bc(1) will not turn TTY mode on. If the environment variable **BC_TTY_MODE** does *not* exist, the default setting is used. The default setting can be queried with the **-h** or **-\-help** options. TTY mode is different from interactive mode because interactive mode is required in the [bc(1) specification][1], and interactive mode requires only **stdin** and **stdout** to be connected to a terminal. ## Command-Line History Command-line history is only enabled if TTY mode is, i.e., that **stdin**, **stdout**, and **stderr** are connected to a TTY and the **BC_TTY_MODE** environment variable (see the **ENVIRONMENT VARIABLES** section) and its default do not disable TTY mode. See the **COMMAND LINE HISTORY** section for more information. ## Prompt If TTY mode is available, then a prompt can be enabled. Like TTY mode itself, it can be turned on or off with an environment variable: **BC_PROMPT** (see the **ENVIRONMENT VARIABLES** section). If the environment variable **BC_PROMPT** exists and is a non-zero integer, then the prompt is turned on when **stdin**, **stdout**, and **stderr** are connected to a TTY and the **-P** and **-\-no-prompt** options were not used. The read prompt will be turned on under the same conditions, except that the **-R** and **-\-no-read-prompt** options must also not be used. However, if **BC_PROMPT** does not exist, the prompt can be enabled or disabled with the **BC_TTY_MODE** environment variable, the **-P** and **-\-no-prompt** options, and the **-R** and **-\-no-read-prompt** options. See the **ENVIRONMENT VARIABLES** and **OPTIONS** sections for more details. # SIGNAL HANDLING Sending a **SIGINT** will cause bc(1) to do one of two things. If bc(1) is not in interactive mode (see the **INTERACTIVE MODE** section), or the **BC_SIGINT_RESET** environment variable (see the **ENVIRONMENT VARIABLES** section), or its default, is either not an integer or it is zero, bc(1) will exit. However, if bc(1) is in interactive mode, and the **BC_SIGINT_RESET** or its default is an integer and non-zero, then bc(1) will stop executing the current input and reset (see the **RESET** section) upon receiving a **SIGINT**. Note that "current input" can mean one of two things. If bc(1) is processing input from **stdin** in interactive mode, it will ask for more input. If bc(1) is processing input from a file in interactive mode, it will stop processing the file and start processing the next file, if one exists, or ask for input from **stdin** if no other file exists. This means that if a **SIGINT** is sent to bc(1) as it is executing a file, it can seem as though bc(1) did not respond to the signal since it will immediately start executing the next file. This is by design; most files that users execute when interacting with bc(1) have function definitions, which are quick to parse. If a file takes a long time to execute, there may be a bug in that file. The rest of the files could still be executed without problem, allowing the user to continue. **SIGTERM** and **SIGQUIT** cause bc(1) to clean up and exit, and it uses the default handler for all other signals. The one exception is **SIGHUP**; in that case, and only when bc(1) is in TTY mode (see the **TTY MODE** section), a **SIGHUP** will cause bc(1) to clean up and exit. # COMMAND LINE HISTORY bc(1) supports interactive command-line editing. If bc(1) can be in TTY mode (see the **TTY MODE** section), history can be enabled. This means that command-line history can only be enabled when **stdin**, **stdout**, and **stderr** are all connected to a TTY. Like TTY mode itself, it can be turned on or off with the environment variable **BC_TTY_MODE** (see the **ENVIRONMENT VARIABLES** section). If history is enabled, previous lines can be recalled and edited with the arrow keys. **Note**: tabs are converted to 8 spaces. # LOCALES This bc(1) ships with support for adding error messages for different locales and thus, supports **LC_MESSAGES**. # SEE ALSO dc(1) # STANDARDS bc(1) is compliant with the [IEEE Std 1003.1-2017 (“POSIX.1-2017”)][1] specification. The flags **-efghiqsvVw**, all long options, and the extensions noted above are extensions to that specification. Note that the specification explicitly says that bc(1) only accepts numbers that use a period (**.**) as a radix point, regardless of the value of **LC_NUMERIC**. This bc(1) supports error messages for different locales, and thus, it supports **LC_MESSAGES**. # BUGS None are known. Report bugs at https://git.yzena.com/gavin/bc. # AUTHORS Gavin D. Howard and contributors. [1]: https://pubs.opengroup.org/onlinepubs/9699919799/utilities/bc.html [2]: https://www.gnu.org/software/bc/ [3]: https://en.wikipedia.org/wiki/Rounding#Round_half_away_from_zero [4]: https://en.wikipedia.org/wiki/Unit_in_the_last_place [5]: https://people.eecs.berkeley.edu/~wkahan/LOG10HAF.TXT [6]: https://en.wikipedia.org/wiki/Rounding#Rounding_away_from_zero diff --git a/contrib/bc/manuals/bc/EH.1 b/contrib/bc/manuals/bc/EH.1 index 0bdfaa9fe14b..4509583a0141 100644 --- a/contrib/bc/manuals/bc/EH.1 +++ b/contrib/bc/manuals/bc/EH.1 @@ -1,1601 +1,1614 @@ .\" .\" SPDX-License-Identifier: BSD-2-Clause .\" .\" Copyright (c) 2018-2021 Gavin D. Howard and contributors. .\" .\" Redistribution and use in source and binary forms, with or without .\" modification, are permitted provided that the following conditions are met: .\" .\" * Redistributions of source code must retain the above copyright notice, .\" this list of conditions and the following disclaimer. .\" .\" * Redistributions in binary form must reproduce the above copyright notice, .\" this list of conditions and the following disclaimer in the documentation .\" and/or other materials provided with the distribution. .\" .\" THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" .\" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE .\" IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE .\" ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE .\" LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR .\" CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF .\" SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS .\" INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN .\" CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) .\" ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE .\" POSSIBILITY OF SUCH DAMAGE. .\" .TH "BC" "1" "June 2021" "Gavin D. Howard" "General Commands Manual" .SH NAME .PP bc - arbitrary-precision decimal arithmetic language and calculator .SH SYNOPSIS .PP \f[B]bc\f[R] [\f[B]-ghilPqRsvVw\f[R]] [\f[B]--global-stacks\f[R]] [\f[B]--help\f[R]] [\f[B]--interactive\f[R]] [\f[B]--mathlib\f[R]] [\f[B]--no-prompt\f[R]] [\f[B]--no-read-prompt\f[R]] [\f[B]--quiet\f[R]] [\f[B]--standard\f[R]] [\f[B]--warn\f[R]] [\f[B]--version\f[R]] [\f[B]-e\f[R] \f[I]expr\f[R]] [\f[B]--expression\f[R]=\f[I]expr\f[R]\&...] [\f[B]-f\f[R] \f[I]file\f[R]\&...] [\f[B]--file\f[R]=\f[I]file\f[R]\&...] [\f[I]file\f[R]\&...] .SH DESCRIPTION .PP bc(1) is an interactive processor for a language first standardized in 1991 by POSIX. (The current standard is here (https://pubs.opengroup.org/onlinepubs/9699919799/utilities/bc.html).) The language provides unlimited precision decimal arithmetic and is somewhat C-like, but there are differences. Such differences will be noted in this document. .PP After parsing and handling options, this bc(1) reads any files given on the command line and executes them before reading from \f[B]stdin\f[R]. .PP This bc(1) is a drop-in replacement for \f[I]any\f[R] bc(1), including (and especially) the GNU bc(1). .PP \f[B]Note\f[R]: If running this bc(1) on \f[I]any\f[R] script meant for another bc(1) gives a parse error, it is probably because a word this bc(1) reserves as a keyword is used as the name of a function, variable, or array. To fix that, use the command-line option \f[B]-r\f[R] \f[I]keyword\f[R], where \f[I]keyword\f[R] is the keyword that is used as a name in the script. For more information, see the \f[B]OPTIONS\f[R] section. .PP If parsing scripts meant for other bc(1) implementations still does not work, that is a bug and should be reported. See the \f[B]BUGS\f[R] section. .SH OPTIONS .PP The following are the options that bc(1) accepts. .TP \f[B]-g\f[R], \f[B]--global-stacks\f[R] Turns the globals \f[B]ibase\f[R], \f[B]obase\f[R], and \f[B]scale\f[R] into stacks. .RS .PP This has the effect that a copy of the current value of all three are pushed onto a stack for every function call, as well as popped when every function returns. This means that functions can assign to any and all of those globals without worrying that the change will affect other functions. Thus, a hypothetical function named \f[B]output(x,b)\f[R] that simply printed \f[B]x\f[R] in base \f[B]b\f[R] could be written like this: .IP .nf \f[C] define void output(x, b) { obase=b x } \f[R] .fi .PP instead of like this: .IP .nf \f[C] define void output(x, b) { auto c c=obase obase=b x obase=c } \f[R] .fi .PP This makes writing functions much easier. .PP However, since using this flag means that functions cannot set \f[B]ibase\f[R], \f[B]obase\f[R], or \f[B]scale\f[R] globally, functions that are made to do so cannot work anymore. There are two possible use cases for that, and each has a solution. .PP First, if a function is called on startup to turn bc(1) into a number converter, it is possible to replace that capability with various shell aliases. Examples: .IP .nf \f[C] alias d2o=\[dq]bc -e ibase=A -e obase=8\[dq] alias h2b=\[dq]bc -e ibase=G -e obase=2\[dq] \f[R] .fi .PP Second, if the purpose of a function is to set \f[B]ibase\f[R], \f[B]obase\f[R], or \f[B]scale\f[R] globally for any other purpose, it could be split into one to three functions (based on how many globals it sets) and each of those functions could return the desired value for a global. .PP If the behavior of this option is desired for every run of bc(1), then users could make sure to define \f[B]BC_ENV_ARGS\f[R] and include this option (see the \f[B]ENVIRONMENT VARIABLES\f[R] section for more details). .PP If \f[B]-s\f[R], \f[B]-w\f[R], or any equivalents are used, this option is ignored. .PP This is a \f[B]non-portable extension\f[R]. .RE .TP \f[B]-h\f[R], \f[B]--help\f[R] Prints a usage message and quits. .TP \f[B]-i\f[R], \f[B]--interactive\f[R] Forces interactive mode. (See the \f[B]INTERACTIVE MODE\f[R] section.) .RS .PP This is a \f[B]non-portable extension\f[R]. .RE .TP \f[B]-L\f[R], \f[B]--no-line-length\f[R] Disables line length checking and prints numbers without backslashes and newlines. In other words, this option sets \f[B]BC_LINE_LENGTH\f[R] to \f[B]0\f[R] (see the \f[B]ENVIRONMENT VARIABLES\f[R] section). .RS .PP This is a \f[B]non-portable extension\f[R]. .RE .TP \f[B]-l\f[R], \f[B]--mathlib\f[R] Sets \f[B]scale\f[R] (see the \f[B]SYNTAX\f[R] section) to \f[B]20\f[R] and loads the included math library before running any code, including any expressions or files specified on the command line. .RS .PP To learn what is in the library, see the \f[B]LIBRARY\f[R] section. .RE .TP \f[B]-P\f[R], \f[B]--no-prompt\f[R] Disables the prompt in TTY mode. (The prompt is only enabled in TTY mode. See the \f[B]TTY MODE\f[R] section.) This is mostly for those users that do not want a prompt or are not used to having them in bc(1). Most of those users would want to put this option in \f[B]BC_ENV_ARGS\f[R] (see the \f[B]ENVIRONMENT VARIABLES\f[R] section). .RS .PP These options override the \f[B]BC_PROMPT\f[R] and \f[B]BC_TTY_MODE\f[R] environment variables (see the \f[B]ENVIRONMENT VARIABLES\f[R] section). .PP This is a \f[B]non-portable extension\f[R]. .RE .TP \f[B]-R\f[R], \f[B]--no-read-prompt\f[R] Disables the read prompt in TTY mode. (The read prompt is only enabled in TTY mode. See the \f[B]TTY MODE\f[R] section.) This is mostly for those users that do not want a read prompt or are not used to having them in bc(1). Most of those users would want to put this option in \f[B]BC_ENV_ARGS\f[R] (see the \f[B]ENVIRONMENT VARIABLES\f[R] section). This option is also useful in hash bang lines of bc(1) scripts that prompt for user input. .RS .PP This option does not disable the regular prompt because the read prompt is only used when the \f[B]read()\f[R] built-in function is called. .PP These options \f[I]do\f[R] override the \f[B]BC_PROMPT\f[R] and \f[B]BC_TTY_MODE\f[R] environment variables (see the \f[B]ENVIRONMENT VARIABLES\f[R] section), but only for the read prompt. .PP This is a \f[B]non-portable extension\f[R]. .RE .TP \f[B]-r\f[R] \f[I]keyword\f[R], \f[B]--redefine\f[R]=\f[I]keyword\f[R] Redefines \f[I]keyword\f[R] in order to allow it to be used as a function, variable, or array name. This is useful when this bc(1) gives parse errors when parsing scripts meant for other bc(1) implementations. .RS .PP The keywords this bc(1) allows to be redefined are: .IP \[bu] 2 \f[B]abs\f[R] .IP \[bu] 2 \f[B]asciify\f[R] .IP \[bu] 2 \f[B]continue\f[R] .IP \[bu] 2 \f[B]divmod\f[R] .IP \[bu] 2 \f[B]else\f[R] .IP \[bu] 2 \f[B]halt\f[R] .IP \[bu] 2 \f[B]last\f[R] .IP \[bu] 2 \f[B]limits\f[R] .IP \[bu] 2 \f[B]maxibase\f[R] .IP \[bu] 2 \f[B]maxobase\f[R] .IP \[bu] 2 \f[B]maxscale\f[R] .IP \[bu] 2 \f[B]modexp\f[R] .IP \[bu] 2 \f[B]print\f[R] .IP \[bu] 2 \f[B]read\f[R] .IP \[bu] 2 \f[B]stream\f[R] .PP If any of those keywords are used as a function, variable, or array name in a script, use this option with the keyword as the argument. If multiple are used, use this option for all of them; it can be used multiple times. .PP Keywords are \f[I]not\f[R] redefined when parsing the builtin math library (see the \f[B]LIBRARY\f[R] section). .PP It is a fatal error to redefine keywords mandated by the POSIX standard. It is a fatal error to attempt to redefine words that this bc(1) does not reserve as keywords. .RE .TP \f[B]-q\f[R], \f[B]--quiet\f[R] This option is for compatibility with the GNU bc(1) (https://www.gnu.org/software/bc/); it is a no-op. Without this option, GNU bc(1) prints a copyright header. This bc(1) only prints the copyright header if one or more of the \f[B]-v\f[R], \f[B]-V\f[R], or \f[B]--version\f[R] options are given. .RS .PP This is a \f[B]non-portable extension\f[R]. .RE .TP \f[B]-s\f[R], \f[B]--standard\f[R] Process exactly the language defined by the standard (https://pubs.opengroup.org/onlinepubs/9699919799/utilities/bc.html) and error if any extensions are used. .RS .PP This is a \f[B]non-portable extension\f[R]. .RE .TP \f[B]-v\f[R], \f[B]-V\f[R], \f[B]--version\f[R] Print the version information (copyright header) and exit. .RS .PP This is a \f[B]non-portable extension\f[R]. .RE .TP \f[B]-w\f[R], \f[B]--warn\f[R] Like \f[B]-s\f[R] and \f[B]--standard\f[R], except that warnings (and not errors) are printed for non-standard extensions and execution continues normally. .RS .PP This is a \f[B]non-portable extension\f[R]. .RE .TP \f[B]-z\f[R], \f[B]--leading-zeroes\f[R] Makes bc(1) print all numbers greater than \f[B]-1\f[R] and less than \f[B]1\f[R], and not equal to \f[B]0\f[R], with a leading zero. .RS .PP This can be set for individual numbers with the \f[B]plz(x)\f[R], plznl(x)**, \f[B]pnlz(x)\f[R], and \f[B]pnlznl(x)\f[R] functions in the extended math library (see the \f[B]LIBRARY\f[R] section). .PP This is a \f[B]non-portable extension\f[R]. .RE .TP \f[B]-e\f[R] \f[I]expr\f[R], \f[B]--expression\f[R]=\f[I]expr\f[R] Evaluates \f[I]expr\f[R]. If multiple expressions are given, they are evaluated in order. If files are given as well (see below), the expressions and files are evaluated in the order given. This means that if a file is given before an expression, the file is read in and evaluated first. .RS .PP If this option is given on the command-line (i.e., not in \f[B]BC_ENV_ARGS\f[R], see the \f[B]ENVIRONMENT VARIABLES\f[R] section), then after processing all expressions and files, bc(1) will exit, unless \f[B]-\f[R] (\f[B]stdin\f[R]) was given as an argument at least once to \f[B]-f\f[R] or \f[B]--file\f[R], whether on the command-line or in \f[B]BC_ENV_ARGS\f[R]. However, if any other \f[B]-e\f[R], \f[B]--expression\f[R], \f[B]-f\f[R], or \f[B]--file\f[R] arguments are given after \f[B]-f-\f[R] or equivalent is given, bc(1) will give a fatal error and exit. .PP This is a \f[B]non-portable extension\f[R]. .RE .TP \f[B]-f\f[R] \f[I]file\f[R], \f[B]--file\f[R]=\f[I]file\f[R] Reads in \f[I]file\f[R] and evaluates it, line by line, as though it were read through \f[B]stdin\f[R]. If expressions are also given (see above), the expressions are evaluated in the order given. .RS .PP If this option is given on the command-line (i.e., not in \f[B]BC_ENV_ARGS\f[R], see the \f[B]ENVIRONMENT VARIABLES\f[R] section), then after processing all expressions and files, bc(1) will exit, unless \f[B]-\f[R] (\f[B]stdin\f[R]) was given as an argument at least once to \f[B]-f\f[R] or \f[B]--file\f[R]. However, if any other \f[B]-e\f[R], \f[B]--expression\f[R], \f[B]-f\f[R], or \f[B]--file\f[R] arguments are given after \f[B]-f-\f[R] or equivalent is given, bc(1) will give a fatal error and exit. .PP This is a \f[B]non-portable extension\f[R]. .RE .PP All long options are \f[B]non-portable extensions\f[R]. .SH STDIN .PP If no files or expressions are given by the \f[B]-f\f[R], \f[B]--file\f[R], \f[B]-e\f[R], or \f[B]--expression\f[R] options, then bc(1) read from \f[B]stdin\f[R]. .PP However, there are a few caveats to this. .PP First, \f[B]stdin\f[R] is evaluated a line at a time. The only exception to this is if the parse cannot complete. That means that starting a string without ending it or starting a function, \f[B]if\f[R] statement, or loop without ending it will also cause bc(1) to not execute. .PP Second, after an \f[B]if\f[R] statement, bc(1) doesn\[cq]t know if an \f[B]else\f[R] statement will follow, so it will not execute until it knows there will not be an \f[B]else\f[R] statement. .SH STDOUT .PP Any non-error output is written to \f[B]stdout\f[R]. In addition, if history (see the \f[B]HISTORY\f[R] section) and the prompt (see the \f[B]TTY MODE\f[R] section) are enabled, both are output to \f[B]stdout\f[R]. .PP \f[B]Note\f[R]: Unlike other bc(1) implementations, this bc(1) will issue a fatal error (see the \f[B]EXIT STATUS\f[R] section) if it cannot write to \f[B]stdout\f[R], so if \f[B]stdout\f[R] is closed, as in \f[B]bc >&-\f[R], it will quit with an error. This is done so that bc(1) can report problems when \f[B]stdout\f[R] is redirected to a file. .PP If there are scripts that depend on the behavior of other bc(1) implementations, it is recommended that those scripts be changed to redirect \f[B]stdout\f[R] to \f[B]/dev/null\f[R]. .SH STDERR .PP Any error output is written to \f[B]stderr\f[R]. .PP \f[B]Note\f[R]: Unlike other bc(1) implementations, this bc(1) will issue a fatal error (see the \f[B]EXIT STATUS\f[R] section) if it cannot write to \f[B]stderr\f[R], so if \f[B]stderr\f[R] is closed, as in \f[B]bc 2>&-\f[R], it will quit with an error. This is done so that bc(1) can exit with an error code when \f[B]stderr\f[R] is redirected to a file. .PP If there are scripts that depend on the behavior of other bc(1) implementations, it is recommended that those scripts be changed to redirect \f[B]stderr\f[R] to \f[B]/dev/null\f[R]. .SH SYNTAX .PP The syntax for bc(1) programs is mostly C-like, with some differences. This bc(1) follows the POSIX standard (https://pubs.opengroup.org/onlinepubs/9699919799/utilities/bc.html), which is a much more thorough resource for the language this bc(1) accepts. This section is meant to be a summary and a listing of all the extensions to the standard. .PP In the sections below, \f[B]E\f[R] means expression, \f[B]S\f[R] means statement, and \f[B]I\f[R] means identifier. .PP Identifiers (\f[B]I\f[R]) start with a lowercase letter and can be followed by any number (up to \f[B]BC_NAME_MAX-1\f[R]) of lowercase letters (\f[B]a-z\f[R]), digits (\f[B]0-9\f[R]), and underscores (\f[B]_\f[R]). The regex is \f[B][a-z][a-z0-9_]*\f[R]. Identifiers with more than one character (letter) are a \f[B]non-portable extension\f[R]. .PP \f[B]ibase\f[R] is a global variable determining how to interpret constant numbers. It is the \[lq]input\[rq] base, or the number base used for interpreting input numbers. \f[B]ibase\f[R] is initially \f[B]10\f[R]. If the \f[B]-s\f[R] (\f[B]--standard\f[R]) and \f[B]-w\f[R] (\f[B]--warn\f[R]) flags were not given on the command line, the max allowable value for \f[B]ibase\f[R] is \f[B]36\f[R]. Otherwise, it is \f[B]16\f[R]. The min allowable value for \f[B]ibase\f[R] is \f[B]2\f[R]. The max allowable value for \f[B]ibase\f[R] can be queried in bc(1) programs with the \f[B]maxibase()\f[R] built-in function. .PP \f[B]obase\f[R] is a global variable determining how to output results. It is the \[lq]output\[rq] base, or the number base used for outputting numbers. \f[B]obase\f[R] is initially \f[B]10\f[R]. The max allowable value for \f[B]obase\f[R] is \f[B]BC_BASE_MAX\f[R] and can be queried in bc(1) programs with the \f[B]maxobase()\f[R] built-in function. The min allowable value for \f[B]obase\f[R] is \f[B]2\f[R]. Values are output in the specified base. .PP The \f[I]scale\f[R] of an expression is the number of digits in the result of the expression right of the decimal point, and \f[B]scale\f[R] is a global variable that sets the precision of any operations, with exceptions. \f[B]scale\f[R] is initially \f[B]0\f[R]. \f[B]scale\f[R] cannot be negative. The max allowable value for \f[B]scale\f[R] is \f[B]BC_SCALE_MAX\f[R] and can be queried in bc(1) programs with the \f[B]maxscale()\f[R] built-in function. .PP bc(1) has both \f[I]global\f[R] variables and \f[I]local\f[R] variables. All \f[I]local\f[R] variables are local to the function; they are parameters or are introduced in the \f[B]auto\f[R] list of a function (see the \f[B]FUNCTIONS\f[R] section). If a variable is accessed which is not a parameter or in the \f[B]auto\f[R] list, it is assumed to be \f[I]global\f[R]. If a parent function has a \f[I]local\f[R] variable version of a variable that a child function considers \f[I]global\f[R], the value of that \f[I]global\f[R] variable in the child function is the value of the variable in the parent function, not the value of the actual \f[I]global\f[R] variable. .PP All of the above applies to arrays as well. .PP The value of a statement that is an expression (i.e., any of the named expressions or operands) is printed unless the lowest precedence operator is an assignment operator \f[I]and\f[R] the expression is notsurrounded by parentheses. .PP The value that is printed is also assigned to the special variable \f[B]last\f[R]. A single dot (\f[B].\f[R]) may also be used as a synonym for \f[B]last\f[R]. These are \f[B]non-portable extensions\f[R]. .PP Either semicolons or newlines may separate statements. .SS Comments .PP There are two kinds of comments: .IP "1." 3 Block comments are enclosed in \f[B]/*\f[R] and \f[B]*/\f[R]. .IP "2." 3 Line comments go from \f[B]#\f[R] until, and not including, the next newline. This is a \f[B]non-portable extension\f[R]. .SS Named Expressions .PP The following are named expressions in bc(1): .IP "1." 3 Variables: \f[B]I\f[R] .IP "2." 3 Array Elements: \f[B]I[E]\f[R] .IP "3." 3 \f[B]ibase\f[R] .IP "4." 3 \f[B]obase\f[R] .IP "5." 3 \f[B]scale\f[R] .IP "6." 3 \f[B]last\f[R] or a single dot (\f[B].\f[R]) .PP Number 6 is a \f[B]non-portable extension\f[R]. .PP Variables and arrays do not interfere; users can have arrays named the same as variables. This also applies to functions (see the \f[B]FUNCTIONS\f[R] section), so a user can have a variable, array, and function that all have the same name, and they will not shadow each other, whether inside of functions or not. .PP Named expressions are required as the operand of \f[B]increment\f[R]/\f[B]decrement\f[R] operators and as the left side of \f[B]assignment\f[R] operators (see the \f[I]Operators\f[R] subsection). .SS Operands .PP The following are valid operands in bc(1): .IP " 1." 4 Numbers (see the \f[I]Numbers\f[R] subsection below). .IP " 2." 4 Array indices (\f[B]I[E]\f[R]). .IP " 3." 4 \f[B](E)\f[R]: The value of \f[B]E\f[R] (used to change precedence). .IP " 4." 4 \f[B]sqrt(E)\f[R]: The square root of \f[B]E\f[R]. \f[B]E\f[R] must be non-negative. .IP " 5." 4 \f[B]length(E)\f[R]: The number of significant decimal digits in \f[B]E\f[R]. Returns \f[B]1\f[R] for \f[B]0\f[R] with no decimal places. If given a string, the length of the string is returned. Passing a string to \f[B]length(E)\f[R] is a \f[B]non-portable extension\f[R]. .IP " 6." 4 \f[B]length(I[])\f[R]: The number of elements in the array \f[B]I\f[R]. This is a \f[B]non-portable extension\f[R]. .IP " 7." 4 \f[B]scale(E)\f[R]: The \f[I]scale\f[R] of \f[B]E\f[R]. .IP " 8." 4 \f[B]abs(E)\f[R]: The absolute value of \f[B]E\f[R]. This is a \f[B]non-portable extension\f[R]. .IP " 9." 4 \f[B]modexp(E, E, E)\f[R]: Modular exponentiation, where the first expression is the base, the second is the exponent, and the third is the modulus. All three values must be integers. The second argument must be non-negative. The third argument must be non-zero. This is a \f[B]non-portable extension\f[R]. .IP "10." 4 \f[B]divmod(E, E, I[])\f[R]: Division and modulus in one operation. This is for optimization. The first expression is the dividend, and the second is the divisor, which must be non-zero. The return value is the quotient, and the modulus is stored in index \f[B]0\f[R] of the provided array (the last argument). This is a \f[B]non-portable extension\f[R]. .IP "11." 4 \f[B]asciify(E)\f[R]: If \f[B]E\f[R] is a string, returns a string that is the first letter of its argument. If it is a number, calculates the number mod \f[B]256\f[R] and returns that number as a one-character string. This is a \f[B]non-portable extension\f[R]. .IP "12." 4 \f[B]I()\f[R], \f[B]I(E)\f[R], \f[B]I(E, E)\f[R], and so on, where \f[B]I\f[R] is an identifier for a non-\f[B]void\f[R] function (see the \f[I]Void Functions\f[R] subsection of the \f[B]FUNCTIONS\f[R] section). The \f[B]E\f[R] argument(s) may also be arrays of the form \f[B]I[]\f[R], which will automatically be turned into array references (see the \f[I]Array References\f[R] subsection of the \f[B]FUNCTIONS\f[R] section) if the corresponding parameter in the function definition is an array reference. .IP "13." 4 \f[B]read()\f[R]: Reads a line from \f[B]stdin\f[R] and uses that as an expression. The result of that expression is the result of the \f[B]read()\f[R] operand. This is a \f[B]non-portable extension\f[R]. .IP "14." 4 \f[B]maxibase()\f[R]: The max allowable \f[B]ibase\f[R]. This is a \f[B]non-portable extension\f[R]. .IP "15." 4 \f[B]maxobase()\f[R]: The max allowable \f[B]obase\f[R]. This is a \f[B]non-portable extension\f[R]. .IP "16." 4 \f[B]maxscale()\f[R]: The max allowable \f[B]scale\f[R]. This is a \f[B]non-portable extension\f[R]. .IP "17." 4 \f[B]line_length()\f[R]: The line length set with \f[B]BC_LINE_LENGTH\f[R] (see the \f[B]ENVIRONMENT VARIABLES\f[R] section). This is a \f[B]non-portable extension\f[R]. .IP "18." 4 \f[B]global_stacks()\f[R]: \f[B]0\f[R] if global stacks are not enabled with the \f[B]-g\f[R] or \f[B]--global-stacks\f[R] options, non-zero otherwise. See the \f[B]OPTIONS\f[R] section. This is a \f[B]non-portable extension\f[R]. .IP "19." 4 \f[B]leading_zero()\f[R]: \f[B]0\f[R] if leading zeroes are not enabled with the \f[B]-z\f[R] or \f[B]\[en]leading-zeroes\f[R] options, non-zero otherwise. See the \f[B]OPTIONS\f[R] section. This is a \f[B]non-portable extension\f[R]. .SS Numbers .PP Numbers are strings made up of digits, uppercase letters, and at most \f[B]1\f[R] period for a radix. Numbers can have up to \f[B]BC_NUM_MAX\f[R] digits. Uppercase letters are equal to \f[B]9\f[R] + their position in the alphabet (i.e., \f[B]A\f[R] equals \f[B]10\f[R], or \f[B]9+1\f[R]). If a digit or letter makes no sense with the current value of \f[B]ibase\f[R], they are set to the value of the highest valid digit in \f[B]ibase\f[R]. .PP Single-character numbers (i.e., \f[B]A\f[R] alone) take the value that they would have if they were valid digits, regardless of the value of \f[B]ibase\f[R]. This means that \f[B]A\f[R] alone always equals decimal \f[B]10\f[R] and \f[B]Z\f[R] alone always equals decimal \f[B]35\f[R]. .SS Operators .PP The following arithmetic and logical operators can be used. They are listed in order of decreasing precedence. Operators in the same group have the same precedence. .TP \f[B]++\f[R] \f[B]--\f[R] Type: Prefix and Postfix .RS .PP Associativity: None .PP Description: \f[B]increment\f[R], \f[B]decrement\f[R] .RE .TP \f[B]-\f[R] \f[B]!\f[R] Type: Prefix .RS .PP Associativity: None .PP Description: \f[B]negation\f[R], \f[B]boolean not\f[R] .RE .TP \f[B]\[ha]\f[R] Type: Binary .RS .PP Associativity: Right .PP Description: \f[B]power\f[R] .RE .TP \f[B]*\f[R] \f[B]/\f[R] \f[B]%\f[R] Type: Binary .RS .PP Associativity: Left .PP Description: \f[B]multiply\f[R], \f[B]divide\f[R], \f[B]modulus\f[R] .RE .TP \f[B]+\f[R] \f[B]-\f[R] Type: Binary .RS .PP Associativity: Left .PP Description: \f[B]add\f[R], \f[B]subtract\f[R] .RE .TP \f[B]=\f[R] \f[B]+=\f[R] \f[B]-=\f[R] \f[B]*=\f[R] \f[B]/=\f[R] \f[B]%=\f[R] \f[B]\[ha]=\f[R] Type: Binary .RS .PP Associativity: Right .PP Description: \f[B]assignment\f[R] .RE .TP \f[B]==\f[R] \f[B]<=\f[R] \f[B]>=\f[R] \f[B]!=\f[R] \f[B]<\f[R] \f[B]>\f[R] Type: Binary .RS .PP Associativity: Left .PP Description: \f[B]relational\f[R] .RE .TP \f[B]&&\f[R] Type: Binary .RS .PP Associativity: Left .PP Description: \f[B]boolean and\f[R] .RE .TP \f[B]||\f[R] Type: Binary .RS .PP Associativity: Left .PP Description: \f[B]boolean or\f[R] .RE .PP The operators will be described in more detail below. .TP \f[B]++\f[R] \f[B]--\f[R] The prefix and postfix \f[B]increment\f[R] and \f[B]decrement\f[R] operators behave exactly like they would in C. They require a named expression (see the \f[I]Named Expressions\f[R] subsection) as an operand. .RS .PP The prefix versions of these operators are more efficient; use them where possible. .RE .TP \f[B]-\f[R] The \f[B]negation\f[R] operator returns \f[B]0\f[R] if a user attempts to negate any expression with the value \f[B]0\f[R]. Otherwise, a copy of the expression with its sign flipped is returned. .TP \f[B]!\f[R] The \f[B]boolean not\f[R] operator returns \f[B]1\f[R] if the expression is \f[B]0\f[R], or \f[B]0\f[R] otherwise. .RS .PP This is a \f[B]non-portable extension\f[R]. .RE .TP \f[B]\[ha]\f[R] The \f[B]power\f[R] operator (not the \f[B]exclusive or\f[R] operator, as it would be in C) takes two expressions and raises the first to the power of the value of the second. The \f[I]scale\f[R] of the result is equal to \f[B]scale\f[R]. .RS .PP The second expression must be an integer (no \f[I]scale\f[R]), and if it is negative, the first value must be non-zero. .RE .TP \f[B]*\f[R] The \f[B]multiply\f[R] operator takes two expressions, multiplies them, and returns the product. If \f[B]a\f[R] is the \f[I]scale\f[R] of the first expression and \f[B]b\f[R] is the \f[I]scale\f[R] of the second expression, the \f[I]scale\f[R] of the result is equal to \f[B]min(a+b,max(scale,a,b))\f[R] where \f[B]min()\f[R] and \f[B]max()\f[R] return the obvious values. .TP \f[B]/\f[R] The \f[B]divide\f[R] operator takes two expressions, divides them, and returns the quotient. The \f[I]scale\f[R] of the result shall be the value of \f[B]scale\f[R]. .RS .PP The second expression must be non-zero. .RE .TP \f[B]%\f[R] The \f[B]modulus\f[R] operator takes two expressions, \f[B]a\f[R] and \f[B]b\f[R], and evaluates them by 1) Computing \f[B]a/b\f[R] to current \f[B]scale\f[R] and 2) Using the result of step 1 to calculate \f[B]a-(a/b)*b\f[R] to \f[I]scale\f[R] \f[B]max(scale+scale(b),scale(a))\f[R]. .RS .PP The second expression must be non-zero. .RE .TP \f[B]+\f[R] The \f[B]add\f[R] operator takes two expressions, \f[B]a\f[R] and \f[B]b\f[R], and returns the sum, with a \f[I]scale\f[R] equal to the max of the \f[I]scale\f[R]s of \f[B]a\f[R] and \f[B]b\f[R]. .TP \f[B]-\f[R] The \f[B]subtract\f[R] operator takes two expressions, \f[B]a\f[R] and \f[B]b\f[R], and returns the difference, with a \f[I]scale\f[R] equal to the max of the \f[I]scale\f[R]s of \f[B]a\f[R] and \f[B]b\f[R]. .TP \f[B]=\f[R] \f[B]+=\f[R] \f[B]-=\f[R] \f[B]*=\f[R] \f[B]/=\f[R] \f[B]%=\f[R] \f[B]\[ha]=\f[R] The \f[B]assignment\f[R] operators take two expressions, \f[B]a\f[R] and \f[B]b\f[R] where \f[B]a\f[R] is a named expression (see the \f[I]Named Expressions\f[R] subsection). .RS .PP For \f[B]=\f[R], \f[B]b\f[R] is copied and the result is assigned to \f[B]a\f[R]. For all others, \f[B]a\f[R] and \f[B]b\f[R] are applied as operands to the corresponding arithmetic operator and the result is assigned to \f[B]a\f[R]. .RE .TP \f[B]==\f[R] \f[B]<=\f[R] \f[B]>=\f[R] \f[B]!=\f[R] \f[B]<\f[R] \f[B]>\f[R] The \f[B]relational\f[R] operators compare two expressions, \f[B]a\f[R] and \f[B]b\f[R], and if the relation holds, according to C language semantics, the result is \f[B]1\f[R]. Otherwise, it is \f[B]0\f[R]. .RS .PP Note that unlike in C, these operators have a lower precedence than the \f[B]assignment\f[R] operators, which means that \f[B]a=b>c\f[R] is interpreted as \f[B](a=b)>c\f[R]. .PP Also, unlike the standard (https://pubs.opengroup.org/onlinepubs/9699919799/utilities/bc.html) requires, these operators can appear anywhere any other expressions can be used. This allowance is a \f[B]non-portable extension\f[R]. .RE .TP \f[B]&&\f[R] The \f[B]boolean and\f[R] operator takes two expressions and returns \f[B]1\f[R] if both expressions are non-zero, \f[B]0\f[R] otherwise. .RS .PP This is \f[I]not\f[R] a short-circuit operator. .PP This is a \f[B]non-portable extension\f[R]. .RE .TP \f[B]||\f[R] The \f[B]boolean or\f[R] operator takes two expressions and returns \f[B]1\f[R] if one of the expressions is non-zero, \f[B]0\f[R] otherwise. .RS .PP This is \f[I]not\f[R] a short-circuit operator. .PP This is a \f[B]non-portable extension\f[R]. .RE .SS Statements .PP The following items are statements: .IP " 1." 4 \f[B]E\f[R] .IP " 2." 4 \f[B]{\f[R] \f[B]S\f[R] \f[B];\f[R] \&... \f[B];\f[R] \f[B]S\f[R] \f[B]}\f[R] .IP " 3." 4 \f[B]if\f[R] \f[B](\f[R] \f[B]E\f[R] \f[B])\f[R] \f[B]S\f[R] .IP " 4." 4 \f[B]if\f[R] \f[B](\f[R] \f[B]E\f[R] \f[B])\f[R] \f[B]S\f[R] \f[B]else\f[R] \f[B]S\f[R] .IP " 5." 4 \f[B]while\f[R] \f[B](\f[R] \f[B]E\f[R] \f[B])\f[R] \f[B]S\f[R] .IP " 6." 4 \f[B]for\f[R] \f[B](\f[R] \f[B]E\f[R] \f[B];\f[R] \f[B]E\f[R] \f[B];\f[R] \f[B]E\f[R] \f[B])\f[R] \f[B]S\f[R] .IP " 7." 4 An empty statement .IP " 8." 4 \f[B]break\f[R] .IP " 9." 4 \f[B]continue\f[R] .IP "10." 4 \f[B]quit\f[R] .IP "11." 4 \f[B]halt\f[R] .IP "12." 4 \f[B]limits\f[R] .IP "13." 4 A string of characters, enclosed in double quotes .IP "14." 4 \f[B]print\f[R] \f[B]E\f[R] \f[B],\f[R] \&... \f[B],\f[R] \f[B]E\f[R] .IP "15." 4 \f[B]stream\f[R] \f[B]E\f[R] \f[B],\f[R] \&... \f[B],\f[R] \f[B]E\f[R] .IP "16." 4 \f[B]I()\f[R], \f[B]I(E)\f[R], \f[B]I(E, E)\f[R], and so on, where \f[B]I\f[R] is an identifier for a \f[B]void\f[R] function (see the \f[I]Void Functions\f[R] subsection of the \f[B]FUNCTIONS\f[R] section). The \f[B]E\f[R] argument(s) may also be arrays of the form \f[B]I[]\f[R], which will automatically be turned into array references (see the \f[I]Array References\f[R] subsection of the \f[B]FUNCTIONS\f[R] section) if the corresponding parameter in the function definition is an array reference. .PP Numbers 4, 9, 11, 12, 14, 15, and 16 are \f[B]non-portable extensions\f[R]. .PP Also, as a \f[B]non-portable extension\f[R], any or all of the expressions in the header of a for loop may be omitted. If the condition (second expression) is omitted, it is assumed to be a constant \f[B]1\f[R]. .PP The \f[B]break\f[R] statement causes a loop to stop iterating and resume execution immediately following a loop. This is only allowed in loops. .PP The \f[B]continue\f[R] statement causes a loop iteration to stop early and returns to the start of the loop, including testing the loop condition. This is only allowed in loops. .PP The \f[B]if\f[R] \f[B]else\f[R] statement does the same thing as in C. .PP The \f[B]quit\f[R] statement causes bc(1) to quit, even if it is on a branch that will not be executed (it is a compile-time command). .PP The \f[B]halt\f[R] statement causes bc(1) to quit, if it is executed. (Unlike \f[B]quit\f[R] if it is on a branch of an \f[B]if\f[R] statement that is not executed, bc(1) does not quit.) .PP The \f[B]limits\f[R] statement prints the limits that this bc(1) is subject to. This is like the \f[B]quit\f[R] statement in that it is a compile-time command. .PP An expression by itself is evaluated and printed, followed by a newline. .SS Strings .PP If strings appear as a statement by themselves, they are printed without a trailing newline. .PP In addition to appearing as a lone statement by themselves, strings can be assigned to variables and array elements. They can also be passed to functions in variable parameters. .PP If any statement that expects a string is given a variable that had a string assigned to it, the statement acts as though it had received a string. .PP If any math operation is attempted on a string or a variable or array element that has been assigned a string, an error is raised, and bc(1) resets (see the \f[B]RESET\f[R] section). .PP Assigning strings to variables and array elements and passing them to functions are \f[B]non-portable extensions\f[R]. .SS Print Statement .PP The \[lq]expressions\[rq] in a \f[B]print\f[R] statement may also be strings. If they are, there are backslash escape sequences that are interpreted specially. What those sequences are, and what they cause to be printed, are shown below: .PP \f[B]\[rs]a\f[R]: \f[B]\[rs]a\f[R] .PP \f[B]\[rs]b\f[R]: \f[B]\[rs]b\f[R] .PP \f[B]\[rs]\[rs]\f[R]: \f[B]\[rs]\f[R] .PP \f[B]\[rs]e\f[R]: \f[B]\[rs]\f[R] .PP \f[B]\[rs]f\f[R]: \f[B]\[rs]f\f[R] .PP \f[B]\[rs]n\f[R]: \f[B]\[rs]n\f[R] .PP \f[B]\[rs]q\f[R]: \f[B]\[lq]\f[R] .PP \f[B]\[rs]r\f[R]: \f[B]\[rs]r\f[R] .PP \f[B]\[rs]t\f[R]: \f[B]\[rs]t\f[R] .PP Any other character following a backslash causes the backslash and character to be printed as-is. .PP Any non-string expression in a print statement shall be assigned to \f[B]last\f[R], like any other expression that is printed. .SS Stream Statement .PP The \[lq]expressions in a \f[B]stream\f[R] statement may also be strings. .PP If a \f[B]stream\f[R] statement is given a string, it prints the string as though the string had appeared as its own statement. In other words, the \f[B]stream\f[R] statement prints strings normally, without a newline. .PP If a \f[B]stream\f[R] statement is given a number, a copy of it is truncated and its absolute value is calculated. The result is then printed as though \f[B]obase\f[R] is \f[B]256\f[R] and each digit is interpreted as an 8-bit ASCII character, making it a byte stream. .SS Order of Evaluation .PP All expressions in a statment are evaluated left to right, except as necessary to maintain order of operations. This means, for example, assuming that \f[B]i\f[R] is equal to \f[B]0\f[R], in the expression .IP .nf \f[C] a[i++] = i++ \f[R] .fi .PP the first (or 0th) element of \f[B]a\f[R] is set to \f[B]1\f[R], and \f[B]i\f[R] is equal to \f[B]2\f[R] at the end of the expression. .PP This includes function arguments. Thus, assuming \f[B]i\f[R] is equal to \f[B]0\f[R], this means that in the expression .IP .nf \f[C] x(i++, i++) \f[R] .fi .PP the first argument passed to \f[B]x()\f[R] is \f[B]0\f[R], and the second argument is \f[B]1\f[R], while \f[B]i\f[R] is equal to \f[B]2\f[R] before the function starts executing. .SH FUNCTIONS .PP Function definitions are as follows: .IP .nf \f[C] define I(I,...,I){ auto I,...,I S;...;S return(E) } \f[R] .fi .PP Any \f[B]I\f[R] in the parameter list or \f[B]auto\f[R] list may be replaced with \f[B]I[]\f[R] to make a parameter or \f[B]auto\f[R] var an array, and any \f[B]I\f[R] in the parameter list may be replaced with \f[B]*I[]\f[R] to make a parameter an array reference. Callers of functions that take array references should not put an asterisk in the call; they must be called with just \f[B]I[]\f[R] like normal array parameters and will be automatically converted into references. .PP As a \f[B]non-portable extension\f[R], the opening brace of a \f[B]define\f[R] statement may appear on the next line. .PP As a \f[B]non-portable extension\f[R], the return statement may also be in one of the following forms: .IP "1." 3 \f[B]return\f[R] .IP "2." 3 \f[B]return\f[R] \f[B](\f[R] \f[B])\f[R] .IP "3." 3 \f[B]return\f[R] \f[B]E\f[R] .PP The first two, or not specifying a \f[B]return\f[R] statement, is equivalent to \f[B]return (0)\f[R], unless the function is a \f[B]void\f[R] function (see the \f[I]Void Functions\f[R] subsection below). .SS Void Functions .PP Functions can also be \f[B]void\f[R] functions, defined as follows: .IP .nf \f[C] define void I(I,...,I){ auto I,...,I S;...;S return } \f[R] .fi .PP They can only be used as standalone expressions, where such an expression would be printed alone, except in a print statement. .PP Void functions can only use the first two \f[B]return\f[R] statements listed above. They can also omit the return statement entirely. .PP The word \[lq]void\[rq] is not treated as a keyword; it is still possible to have variables, arrays, and functions named \f[B]void\f[R]. The word \[lq]void\[rq] is only treated specially right after the \f[B]define\f[R] keyword. .PP This is a \f[B]non-portable extension\f[R]. .SS Array References .PP For any array in the parameter list, if the array is declared in the form .IP .nf \f[C] *I[] \f[R] .fi .PP it is a \f[B]reference\f[R]. Any changes to the array in the function are reflected, when the function returns, to the array that was passed in. .PP Other than this, all function arguments are passed by value. .PP This is a \f[B]non-portable extension\f[R]. .SH LIBRARY .PP All of the functions below are available when the \f[B]-l\f[R] or \f[B]--mathlib\f[R] command-line flags are given. .SS Standard Library .PP The standard (https://pubs.opengroup.org/onlinepubs/9699919799/utilities/bc.html) defines the following functions for the math library: .TP \f[B]s(x)\f[R] Returns the sine of \f[B]x\f[R], which is assumed to be in radians. .RS .PP This is a transcendental function (see the \f[I]Transcendental Functions\f[R] subsection below). .RE .TP \f[B]c(x)\f[R] Returns the cosine of \f[B]x\f[R], which is assumed to be in radians. .RS .PP This is a transcendental function (see the \f[I]Transcendental Functions\f[R] subsection below). .RE .TP \f[B]a(x)\f[R] Returns the arctangent of \f[B]x\f[R], in radians. .RS .PP This is a transcendental function (see the \f[I]Transcendental Functions\f[R] subsection below). .RE .TP \f[B]l(x)\f[R] Returns the natural logarithm of \f[B]x\f[R]. .RS .PP This is a transcendental function (see the \f[I]Transcendental Functions\f[R] subsection below). .RE .TP \f[B]e(x)\f[R] Returns the mathematical constant \f[B]e\f[R] raised to the power of \f[B]x\f[R]. .RS .PP This is a transcendental function (see the \f[I]Transcendental Functions\f[R] subsection below). .RE .TP \f[B]j(x, n)\f[R] Returns the bessel integer order \f[B]n\f[R] (truncated) of \f[B]x\f[R]. .RS .PP This is a transcendental function (see the \f[I]Transcendental Functions\f[R] subsection below). .RE .SS Transcendental Functions .PP All transcendental functions can return slightly inaccurate results (up to 1 ULP (https://en.wikipedia.org/wiki/Unit_in_the_last_place)). This is unavoidable, and this article (https://people.eecs.berkeley.edu/~wkahan/LOG10HAF.TXT) explains why it is impossible and unnecessary to calculate exact results for the transcendental functions. .PP Because of the possible inaccuracy, I recommend that users call those functions with the precision (\f[B]scale\f[R]) set to at least 1 higher than is necessary. If exact results are \f[I]absolutely\f[R] required, users can double the precision (\f[B]scale\f[R]) and then truncate. .PP The transcendental functions in the standard math library are: .IP \[bu] 2 \f[B]s(x)\f[R] .IP \[bu] 2 \f[B]c(x)\f[R] .IP \[bu] 2 \f[B]a(x)\f[R] .IP \[bu] 2 \f[B]l(x)\f[R] .IP \[bu] 2 \f[B]e(x)\f[R] .IP \[bu] 2 \f[B]j(x, n)\f[R] .SH RESET .PP When bc(1) encounters an error or a signal that it has a non-default handler for, it resets. This means that several things happen. .PP First, any functions that are executing are stopped and popped off the stack. The behavior is not unlike that of exceptions in programming languages. Then the execution point is set so that any code waiting to execute (after all functions returned) is skipped. .PP Thus, when bc(1) resets, it skips any remaining code waiting to be executed. Then, if it is interactive mode, and the error was not a fatal error (see the \f[B]EXIT STATUS\f[R] section), it asks for more input; otherwise, it exits with the appropriate return code. .PP Note that this reset behavior is different from the GNU bc(1), which attempts to start executing the statement right after the one that caused an error. .SH PERFORMANCE .PP Most bc(1) implementations use \f[B]char\f[R] types to calculate the value of \f[B]1\f[R] decimal digit at a time, but that can be slow. This bc(1) does something different. .PP It uses large integers to calculate more than \f[B]1\f[R] decimal digit at a time. If built in a environment where \f[B]BC_LONG_BIT\f[R] (see the \f[B]LIMITS\f[R] section) is \f[B]64\f[R], then each integer has \f[B]9\f[R] decimal digits. If built in an environment where \f[B]BC_LONG_BIT\f[R] is \f[B]32\f[R] then each integer has \f[B]4\f[R] decimal digits. This value (the number of decimal digits per large integer) is called \f[B]BC_BASE_DIGS\f[R]. .PP The actual values of \f[B]BC_LONG_BIT\f[R] and \f[B]BC_BASE_DIGS\f[R] can be queried with the \f[B]limits\f[R] statement. .PP In addition, this bc(1) uses an even larger integer for overflow checking. This integer type depends on the value of \f[B]BC_LONG_BIT\f[R], but is always at least twice as large as the integer type used to store digits. .SH LIMITS .PP The following are the limits on bc(1): .TP \f[B]BC_LONG_BIT\f[R] The number of bits in the \f[B]long\f[R] type in the environment where bc(1) was built. This determines how many decimal digits can be stored in a single large integer (see the \f[B]PERFORMANCE\f[R] section). .TP \f[B]BC_BASE_DIGS\f[R] The number of decimal digits per large integer (see the \f[B]PERFORMANCE\f[R] section). Depends on \f[B]BC_LONG_BIT\f[R]. .TP \f[B]BC_BASE_POW\f[R] The max decimal number that each large integer can store (see \f[B]BC_BASE_DIGS\f[R]) plus \f[B]1\f[R]. Depends on \f[B]BC_BASE_DIGS\f[R]. .TP \f[B]BC_OVERFLOW_MAX\f[R] The max number that the overflow type (see the \f[B]PERFORMANCE\f[R] section) can hold. Depends on \f[B]BC_LONG_BIT\f[R]. .TP \f[B]BC_BASE_MAX\f[R] The maximum output base. Set at \f[B]BC_BASE_POW\f[R]. .TP \f[B]BC_DIM_MAX\f[R] The maximum size of arrays. Set at \f[B]SIZE_MAX-1\f[R]. .TP \f[B]BC_SCALE_MAX\f[R] The maximum \f[B]scale\f[R]. Set at \f[B]BC_OVERFLOW_MAX-1\f[R]. .TP \f[B]BC_STRING_MAX\f[R] The maximum length of strings. Set at \f[B]BC_OVERFLOW_MAX-1\f[R]. .TP \f[B]BC_NAME_MAX\f[R] The maximum length of identifiers. Set at \f[B]BC_OVERFLOW_MAX-1\f[R]. .TP \f[B]BC_NUM_MAX\f[R] The maximum length of a number (in decimal digits), which includes digits after the decimal point. Set at \f[B]BC_OVERFLOW_MAX-1\f[R]. .TP Exponent The maximum allowable exponent (positive or negative). Set at \f[B]BC_OVERFLOW_MAX\f[R]. .TP Number of vars The maximum number of vars/arrays. Set at \f[B]SIZE_MAX-1\f[R]. .PP The actual values can be queried with the \f[B]limits\f[R] statement. .PP These limits are meant to be effectively non-existent; the limits are so large (at least on 64-bit machines) that there should not be any point at which they become a problem. In fact, memory should be exhausted before these limits should be hit. .SH ENVIRONMENT VARIABLES .PP bc(1) recognizes the following environment variables: .TP \f[B]POSIXLY_CORRECT\f[R] If this variable exists (no matter the contents), bc(1) behaves as if the \f[B]-s\f[R] option was given. .TP \f[B]BC_ENV_ARGS\f[R] This is another way to give command-line arguments to bc(1). They should be in the same format as all other command-line arguments. These are always processed first, so any files given in \f[B]BC_ENV_ARGS\f[R] will be processed before arguments and files given on the command-line. This gives the user the ability to set up \[lq]standard\[rq] options and files to be used at every invocation. The most useful thing for such files to contain would be useful functions that the user might want every time bc(1) runs. .RS .PP The code that parses \f[B]BC_ENV_ARGS\f[R] will correctly handle quoted arguments, but it does not understand escape sequences. For example, the string \f[B]\[lq]/home/gavin/some bc file.bc\[rq]\f[R] will be correctly parsed, but the string \f[B]\[lq]/home/gavin/some \[dq]bc\[dq] file.bc\[rq]\f[R] will include the backslashes. .PP The quote parsing will handle either kind of quotes, \f[B]\[cq]\f[R] or \f[B]\[lq]\f[R]. Thus, if you have a file with any number of single quotes in the name, you can use double quotes as the outside quotes, as in \f[B]\[lq]some `bc' file.bc\[rq]\f[R], and vice versa if you have a file with double quotes. However, handling a file with both kinds of quotes in \f[B]BC_ENV_ARGS\f[R] is not supported due to the complexity of the parsing, though such files are still supported on the command-line where the parsing is done by the shell. .RE .TP \f[B]BC_LINE_LENGTH\f[R] If this environment variable exists and contains an integer that is greater than \f[B]1\f[R] and is less than \f[B]UINT16_MAX\f[R] (\f[B]2\[ha]16-1\f[R]), bc(1) will output lines to that length, including the backslash (\f[B]\[rs]\f[R]). The default line length is \f[B]70\f[R]. .RS .PP The special value of \f[B]0\f[R] will disable line length checking and print numbers without regard to line length and without backslashes and newlines. .RE .TP \f[B]BC_BANNER\f[R] If this environment variable exists and contains an integer, then a non-zero value activates the copyright banner when bc(1) is in interactive mode, while zero deactivates it. .RS .PP If bc(1) is not in interactive mode (see the \f[B]INTERACTIVE MODE\f[R] section), then this environment variable has no effect because bc(1) does not print the banner when not in interactive mode. .PP This environment variable overrides the default, which can be queried with the \f[B]-h\f[R] or \f[B]--help\f[R] options. .RE .TP \f[B]BC_SIGINT_RESET\f[R] If bc(1) is not in interactive mode (see the \f[B]INTERACTIVE MODE\f[R] section), then this environment variable has no effect because bc(1) exits on \f[B]SIGINT\f[R] when not in interactive mode. .RS .PP However, when bc(1) is in interactive mode, then if this environment variable exists and contains an integer, a non-zero value makes bc(1) reset on \f[B]SIGINT\f[R], rather than exit, and zero makes bc(1) exit. If this environment variable exists and is \f[I]not\f[R] an integer, then bc(1) will exit on \f[B]SIGINT\f[R]. .PP This environment variable overrides the default, which can be queried with the \f[B]-h\f[R] or \f[B]--help\f[R] options. .RE .TP \f[B]BC_TTY_MODE\f[R] If TTY mode is \f[I]not\f[R] available (see the \f[B]TTY MODE\f[R] section), then this environment variable has no effect. .RS .PP However, when TTY mode is available, then if this environment variable exists and contains an integer, then a non-zero value makes bc(1) use TTY mode, and zero makes bc(1) not use TTY mode. .PP This environment variable overrides the default, which can be queried with the \f[B]-h\f[R] or \f[B]--help\f[R] options. .RE .TP \f[B]BC_PROMPT\f[R] If TTY mode is \f[I]not\f[R] available (see the \f[B]TTY MODE\f[R] section), then this environment variable has no effect. .RS .PP However, when TTY mode is available, then if this environment variable exists and contains an integer, a non-zero value makes bc(1) use a prompt, and zero or a non-integer makes bc(1) not use a prompt. If this environment variable does not exist and \f[B]BC_TTY_MODE\f[R] does, then the value of the \f[B]BC_TTY_MODE\f[R] environment variable is used. .PP This environment variable and the \f[B]BC_TTY_MODE\f[R] environment variable override the default, which can be queried with the \f[B]-h\f[R] or \f[B]--help\f[R] options. .RE +.TP +\f[B]BC_EXPR_EXIT\f[R] +If any expressions or expression files are given on the command-line +with \f[B]-e\f[R], \f[B]--expression\f[R], \f[B]-f\f[R], or +\f[B]--file\f[R], then if this environment variable exists and contains +an integer, a non-zero value makes bc(1) exit after executing the +expressions and expression files, and a non-zero value makes bc(1) not +exit. +.RS +.PP +This environment variable overrides the default, which can be queried +with the \f[B]-h\f[R] or \f[B]--help\f[R] options. +.RE .SH EXIT STATUS .PP bc(1) returns the following exit statuses: .TP \f[B]0\f[R] No error. .TP \f[B]1\f[R] A math error occurred. This follows standard practice of using \f[B]1\f[R] for expected errors, since math errors will happen in the process of normal execution. .RS .PP Math errors include divide by \f[B]0\f[R], taking the square root of a negative number, attempting to convert a negative number to a hardware integer, overflow when converting a number to a hardware integer, overflow when calculating the size of a number, and attempting to use a non-integer where an integer is required. .PP Converting to a hardware integer happens for the second operand of the power (\f[B]\[ha]\f[R]) operator and the corresponding assignment operator. .RE .TP \f[B]2\f[R] A parse error occurred. .RS .PP Parse errors include unexpected \f[B]EOF\f[R], using an invalid character, failing to find the end of a string or comment, using a token where it is invalid, giving an invalid expression, giving an invalid print statement, giving an invalid function definition, attempting to assign to an expression that is not a named expression (see the \f[I]Named Expressions\f[R] subsection of the \f[B]SYNTAX\f[R] section), giving an invalid \f[B]auto\f[R] list, having a duplicate \f[B]auto\f[R]/function parameter, failing to find the end of a code block, attempting to return a value from a \f[B]void\f[R] function, attempting to use a variable as a reference, and using any extensions when the option \f[B]-s\f[R] or any equivalents were given. .RE .TP \f[B]3\f[R] A runtime error occurred. .RS .PP Runtime errors include assigning an invalid number to any global (\f[B]ibase\f[R], \f[B]obase\f[R], or \f[B]scale\f[R]), giving a bad expression to a \f[B]read()\f[R] call, calling \f[B]read()\f[R] inside of a \f[B]read()\f[R] call, type errors, passing the wrong number of arguments to functions, attempting to call an undefined function, and attempting to use a \f[B]void\f[R] function call as a value in an expression. .RE .TP \f[B]4\f[R] A fatal error occurred. .RS .PP Fatal errors include memory allocation errors, I/O errors, failing to open files, attempting to use files that do not have only ASCII characters (bc(1) only accepts ASCII characters), attempting to open a directory as a file, and giving invalid command-line options. .RE .PP The exit status \f[B]4\f[R] is special; when a fatal error occurs, bc(1) always exits and returns \f[B]4\f[R], no matter what mode bc(1) is in. .PP The other statuses will only be returned when bc(1) is not in interactive mode (see the \f[B]INTERACTIVE MODE\f[R] section), since bc(1) resets its state (see the \f[B]RESET\f[R] section) and accepts more input when one of those errors occurs in interactive mode. This is also the case when interactive mode is forced by the \f[B]-i\f[R] flag or \f[B]--interactive\f[R] option. .PP These exit statuses allow bc(1) to be used in shell scripting with error checking, and its normal behavior can be forced by using the \f[B]-i\f[R] flag or \f[B]--interactive\f[R] option. .SH INTERACTIVE MODE .PP Per the standard (https://pubs.opengroup.org/onlinepubs/9699919799/utilities/bc.html), bc(1) has an interactive mode and a non-interactive mode. Interactive mode is turned on automatically when both \f[B]stdin\f[R] and \f[B]stdout\f[R] are hooked to a terminal, but the \f[B]-i\f[R] flag and \f[B]--interactive\f[R] option can turn it on in other situations. .PP In interactive mode, bc(1) attempts to recover from errors (see the \f[B]RESET\f[R] section), and in normal execution, flushes \f[B]stdout\f[R] as soon as execution is done for the current input. bc(1) may also reset on \f[B]SIGINT\f[R] instead of exit, depending on the contents of, or default for, the \f[B]BC_SIGINT_RESET\f[R] environment variable (see the \f[B]ENVIRONMENT VARIABLES\f[R] section). .SH TTY MODE .PP If \f[B]stdin\f[R], \f[B]stdout\f[R], and \f[B]stderr\f[R] are all connected to a TTY, then \[lq]TTY mode\[rq] is considered to be available, and thus, bc(1) can turn on TTY mode, subject to some settings. .PP If there is the environment variable \f[B]BC_TTY_MODE\f[R] in the environment (see the \f[B]ENVIRONMENT VARIABLES\f[R] section), then if that environment variable contains a non-zero integer, bc(1) will turn on TTY mode when \f[B]stdin\f[R], \f[B]stdout\f[R], and \f[B]stderr\f[R] are all connected to a TTY. If the \f[B]BC_TTY_MODE\f[R] environment variable exists but is \f[I]not\f[R] a non-zero integer, then bc(1) will not turn TTY mode on. .PP If the environment variable \f[B]BC_TTY_MODE\f[R] does \f[I]not\f[R] exist, the default setting is used. The default setting can be queried with the \f[B]-h\f[R] or \f[B]--help\f[R] options. .PP TTY mode is different from interactive mode because interactive mode is required in the bc(1) specification (https://pubs.opengroup.org/onlinepubs/9699919799/utilities/bc.html), and interactive mode requires only \f[B]stdin\f[R] and \f[B]stdout\f[R] to be connected to a terminal. .SS Prompt .PP If TTY mode is available, then a prompt can be enabled. Like TTY mode itself, it can be turned on or off with an environment variable: \f[B]BC_PROMPT\f[R] (see the \f[B]ENVIRONMENT VARIABLES\f[R] section). .PP If the environment variable \f[B]BC_PROMPT\f[R] exists and is a non-zero integer, then the prompt is turned on when \f[B]stdin\f[R], \f[B]stdout\f[R], and \f[B]stderr\f[R] are connected to a TTY and the \f[B]-P\f[R] and \f[B]--no-prompt\f[R] options were not used. The read prompt will be turned on under the same conditions, except that the \f[B]-R\f[R] and \f[B]--no-read-prompt\f[R] options must also not be used. .PP However, if \f[B]BC_PROMPT\f[R] does not exist, the prompt can be enabled or disabled with the \f[B]BC_TTY_MODE\f[R] environment variable, the \f[B]-P\f[R] and \f[B]--no-prompt\f[R] options, and the \f[B]-R\f[R] and \f[B]--no-read-prompt\f[R] options. See the \f[B]ENVIRONMENT VARIABLES\f[R] and \f[B]OPTIONS\f[R] sections for more details. .SH SIGNAL HANDLING .PP Sending a \f[B]SIGINT\f[R] will cause bc(1) to do one of two things. .PP If bc(1) is not in interactive mode (see the \f[B]INTERACTIVE MODE\f[R] section), or the \f[B]BC_SIGINT_RESET\f[R] environment variable (see the \f[B]ENVIRONMENT VARIABLES\f[R] section), or its default, is either not an integer or it is zero, bc(1) will exit. .PP However, if bc(1) is in interactive mode, and the \f[B]BC_SIGINT_RESET\f[R] or its default is an integer and non-zero, then bc(1) will stop executing the current input and reset (see the \f[B]RESET\f[R] section) upon receiving a \f[B]SIGINT\f[R]. .PP Note that \[lq]current input\[rq] can mean one of two things. If bc(1) is processing input from \f[B]stdin\f[R] in interactive mode, it will ask for more input. If bc(1) is processing input from a file in interactive mode, it will stop processing the file and start processing the next file, if one exists, or ask for input from \f[B]stdin\f[R] if no other file exists. .PP This means that if a \f[B]SIGINT\f[R] is sent to bc(1) as it is executing a file, it can seem as though bc(1) did not respond to the signal since it will immediately start executing the next file. This is by design; most files that users execute when interacting with bc(1) have function definitions, which are quick to parse. If a file takes a long time to execute, there may be a bug in that file. The rest of the files could still be executed without problem, allowing the user to continue. .PP \f[B]SIGTERM\f[R] and \f[B]SIGQUIT\f[R] cause bc(1) to clean up and exit, and it uses the default handler for all other signals. .SH LOCALES .PP This bc(1) ships with support for adding error messages for different locales and thus, supports \f[B]LC_MESSAGES\f[R]. .SH SEE ALSO .PP dc(1) .SH STANDARDS .PP bc(1) is compliant with the IEEE Std 1003.1-2017 (\[lq]POSIX.1-2017\[rq]) (https://pubs.opengroup.org/onlinepubs/9699919799/utilities/bc.html) specification. The flags \f[B]-efghiqsvVw\f[R], all long options, and the extensions noted above are extensions to that specification. .PP Note that the specification explicitly says that bc(1) only accepts numbers that use a period (\f[B].\f[R]) as a radix point, regardless of the value of \f[B]LC_NUMERIC\f[R]. .PP This bc(1) supports error messages for different locales, and thus, it supports \f[B]LC_MESSAGES\f[R]. .SH BUGS .PP None are known. Report bugs at https://git.yzena.com/gavin/bc. .SH AUTHORS .PP Gavin D. Howard and contributors. diff --git a/contrib/bc/manuals/bc/EH.1.md b/contrib/bc/manuals/bc/EH.1.md index 044330b7fe0a..2178c375cb92 100644 --- a/contrib/bc/manuals/bc/EH.1.md +++ b/contrib/bc/manuals/bc/EH.1.md @@ -1,1339 +1,1350 @@ # NAME bc - arbitrary-precision decimal arithmetic language and calculator # SYNOPSIS **bc** [**-ghilPqRsvVw**] [**-\-global-stacks**] [**-\-help**] [**-\-interactive**] [**-\-mathlib**] [**-\-no-prompt**] [**-\-no-read-prompt**] [**-\-quiet**] [**-\-standard**] [**-\-warn**] [**-\-version**] [**-e** *expr*] [**-\-expression**=*expr*...] [**-f** *file*...] [**-\-file**=*file*...] [*file*...] # DESCRIPTION bc(1) is an interactive processor for a language first standardized in 1991 by POSIX. (The current standard is [here][1].) The language provides unlimited precision decimal arithmetic and is somewhat C-like, but there are differences. Such differences will be noted in this document. After parsing and handling options, this bc(1) reads any files given on the command line and executes them before reading from **stdin**. This bc(1) is a drop-in replacement for *any* bc(1), including (and especially) the GNU bc(1). **Note**: If running this bc(1) on *any* script meant for another bc(1) gives a parse error, it is probably because a word this bc(1) reserves as a keyword is used as the name of a function, variable, or array. To fix that, use the command-line option **-r** *keyword*, where *keyword* is the keyword that is used as a name in the script. For more information, see the **OPTIONS** section. If parsing scripts meant for other bc(1) implementations still does not work, that is a bug and should be reported. See the **BUGS** section. # OPTIONS The following are the options that bc(1) accepts. **-g**, **-\-global-stacks** : Turns the globals **ibase**, **obase**, and **scale** into stacks. This has the effect that a copy of the current value of all three are pushed onto a stack for every function call, as well as popped when every function returns. This means that functions can assign to any and all of those globals without worrying that the change will affect other functions. Thus, a hypothetical function named **output(x,b)** that simply printed **x** in base **b** could be written like this: define void output(x, b) { obase=b x } instead of like this: define void output(x, b) { auto c c=obase obase=b x obase=c } This makes writing functions much easier. However, since using this flag means that functions cannot set **ibase**, **obase**, or **scale** globally, functions that are made to do so cannot work anymore. There are two possible use cases for that, and each has a solution. First, if a function is called on startup to turn bc(1) into a number converter, it is possible to replace that capability with various shell aliases. Examples: alias d2o="bc -e ibase=A -e obase=8" alias h2b="bc -e ibase=G -e obase=2" Second, if the purpose of a function is to set **ibase**, **obase**, or **scale** globally for any other purpose, it could be split into one to three functions (based on how many globals it sets) and each of those functions could return the desired value for a global. If the behavior of this option is desired for every run of bc(1), then users could make sure to define **BC_ENV_ARGS** and include this option (see the **ENVIRONMENT VARIABLES** section for more details). If **-s**, **-w**, or any equivalents are used, this option is ignored. This is a **non-portable extension**. **-h**, **-\-help** : Prints a usage message and quits. **-i**, **-\-interactive** : Forces interactive mode. (See the **INTERACTIVE MODE** section.) This is a **non-portable extension**. **-L**, **-\-no-line-length** : Disables line length checking and prints numbers without backslashes and newlines. In other words, this option sets **BC_LINE_LENGTH** to **0** (see the **ENVIRONMENT VARIABLES** section). This is a **non-portable extension**. **-l**, **-\-mathlib** : Sets **scale** (see the **SYNTAX** section) to **20** and loads the included math library before running any code, including any expressions or files specified on the command line. To learn what is in the library, see the **LIBRARY** section. **-P**, **-\-no-prompt** : Disables the prompt in TTY mode. (The prompt is only enabled in TTY mode. See the **TTY MODE** section.) This is mostly for those users that do not want a prompt or are not used to having them in bc(1). Most of those users would want to put this option in **BC_ENV_ARGS** (see the **ENVIRONMENT VARIABLES** section). These options override the **BC_PROMPT** and **BC_TTY_MODE** environment variables (see the **ENVIRONMENT VARIABLES** section). This is a **non-portable extension**. **-R**, **-\-no-read-prompt** : Disables the read prompt in TTY mode. (The read prompt is only enabled in TTY mode. See the **TTY MODE** section.) This is mostly for those users that do not want a read prompt or are not used to having them in bc(1). Most of those users would want to put this option in **BC_ENV_ARGS** (see the **ENVIRONMENT VARIABLES** section). This option is also useful in hash bang lines of bc(1) scripts that prompt for user input. This option does not disable the regular prompt because the read prompt is only used when the **read()** built-in function is called. These options *do* override the **BC_PROMPT** and **BC_TTY_MODE** environment variables (see the **ENVIRONMENT VARIABLES** section), but only for the read prompt. This is a **non-portable extension**. **-r** *keyword*, **-\-redefine**=*keyword* : Redefines *keyword* in order to allow it to be used as a function, variable, or array name. This is useful when this bc(1) gives parse errors when parsing scripts meant for other bc(1) implementations. The keywords this bc(1) allows to be redefined are: * **abs** * **asciify** * **continue** * **divmod** * **else** * **halt** * **last** * **limits** * **maxibase** * **maxobase** * **maxscale** * **modexp** * **print** * **read** * **stream** If any of those keywords are used as a function, variable, or array name in a script, use this option with the keyword as the argument. If multiple are used, use this option for all of them; it can be used multiple times. Keywords are *not* redefined when parsing the builtin math library (see the **LIBRARY** section). It is a fatal error to redefine keywords mandated by the POSIX standard. It is a fatal error to attempt to redefine words that this bc(1) does not reserve as keywords. **-q**, **-\-quiet** : This option is for compatibility with the [GNU bc(1)][2]; it is a no-op. Without this option, GNU bc(1) prints a copyright header. This bc(1) only prints the copyright header if one or more of the **-v**, **-V**, or **-\-version** options are given. This is a **non-portable extension**. **-s**, **-\-standard** : Process exactly the language defined by the [standard][1] and error if any extensions are used. This is a **non-portable extension**. **-v**, **-V**, **-\-version** : Print the version information (copyright header) and exit. This is a **non-portable extension**. **-w**, **-\-warn** : Like **-s** and **-\-standard**, except that warnings (and not errors) are printed for non-standard extensions and execution continues normally. This is a **non-portable extension**. **-z**, **-\-leading-zeroes** : Makes bc(1) print all numbers greater than **-1** and less than **1**, and not equal to **0**, with a leading zero. This can be set for individual numbers with the **plz(x)**, plznl(x)**, **pnlz(x)**, and **pnlznl(x)** functions in the extended math library (see the **LIBRARY** section). This is a **non-portable extension**. **-e** *expr*, **-\-expression**=*expr* : Evaluates *expr*. If multiple expressions are given, they are evaluated in order. If files are given as well (see below), the expressions and files are evaluated in the order given. This means that if a file is given before an expression, the file is read in and evaluated first. If this option is given on the command-line (i.e., not in **BC_ENV_ARGS**, see the **ENVIRONMENT VARIABLES** section), then after processing all expressions and files, bc(1) will exit, unless **-** (**stdin**) was given as an argument at least once to **-f** or **-\-file**, whether on the command-line or in **BC_ENV_ARGS**. However, if any other **-e**, **-\-expression**, **-f**, or **-\-file** arguments are given after **-f-** or equivalent is given, bc(1) will give a fatal error and exit. This is a **non-portable extension**. **-f** *file*, **-\-file**=*file* : Reads in *file* and evaluates it, line by line, as though it were read through **stdin**. If expressions are also given (see above), the expressions are evaluated in the order given. If this option is given on the command-line (i.e., not in **BC_ENV_ARGS**, see the **ENVIRONMENT VARIABLES** section), then after processing all expressions and files, bc(1) will exit, unless **-** (**stdin**) was given as an argument at least once to **-f** or **-\-file**. However, if any other **-e**, **-\-expression**, **-f**, or **-\-file** arguments are given after **-f-** or equivalent is given, bc(1) will give a fatal error and exit. This is a **non-portable extension**. All long options are **non-portable extensions**. # STDIN If no files or expressions are given by the **-f**, **-\-file**, **-e**, or **-\-expression** options, then bc(1) read from **stdin**. However, there are a few caveats to this. First, **stdin** is evaluated a line at a time. The only exception to this is if the parse cannot complete. That means that starting a string without ending it or starting a function, **if** statement, or loop without ending it will also cause bc(1) to not execute. Second, after an **if** statement, bc(1) doesn't know if an **else** statement will follow, so it will not execute until it knows there will not be an **else** statement. # STDOUT Any non-error output is written to **stdout**. In addition, if history (see the **HISTORY** section) and the prompt (see the **TTY MODE** section) are enabled, both are output to **stdout**. **Note**: Unlike other bc(1) implementations, this bc(1) will issue a fatal error (see the **EXIT STATUS** section) if it cannot write to **stdout**, so if **stdout** is closed, as in **bc >&-**, it will quit with an error. This is done so that bc(1) can report problems when **stdout** is redirected to a file. If there are scripts that depend on the behavior of other bc(1) implementations, it is recommended that those scripts be changed to redirect **stdout** to **/dev/null**. # STDERR Any error output is written to **stderr**. **Note**: Unlike other bc(1) implementations, this bc(1) will issue a fatal error (see the **EXIT STATUS** section) if it cannot write to **stderr**, so if **stderr** is closed, as in **bc 2>&-**, it will quit with an error. This is done so that bc(1) can exit with an error code when **stderr** is redirected to a file. If there are scripts that depend on the behavior of other bc(1) implementations, it is recommended that those scripts be changed to redirect **stderr** to **/dev/null**. # SYNTAX The syntax for bc(1) programs is mostly C-like, with some differences. This bc(1) follows the [POSIX standard][1], which is a much more thorough resource for the language this bc(1) accepts. This section is meant to be a summary and a listing of all the extensions to the standard. In the sections below, **E** means expression, **S** means statement, and **I** means identifier. Identifiers (**I**) start with a lowercase letter and can be followed by any number (up to **BC_NAME_MAX-1**) of lowercase letters (**a-z**), digits (**0-9**), and underscores (**\_**). The regex is **\[a-z\]\[a-z0-9\_\]\***. Identifiers with more than one character (letter) are a **non-portable extension**. **ibase** is a global variable determining how to interpret constant numbers. It is the "input" base, or the number base used for interpreting input numbers. **ibase** is initially **10**. If the **-s** (**-\-standard**) and **-w** (**-\-warn**) flags were not given on the command line, the max allowable value for **ibase** is **36**. Otherwise, it is **16**. The min allowable value for **ibase** is **2**. The max allowable value for **ibase** can be queried in bc(1) programs with the **maxibase()** built-in function. **obase** is a global variable determining how to output results. It is the "output" base, or the number base used for outputting numbers. **obase** is initially **10**. The max allowable value for **obase** is **BC_BASE_MAX** and can be queried in bc(1) programs with the **maxobase()** built-in function. The min allowable value for **obase** is **2**. Values are output in the specified base. The *scale* of an expression is the number of digits in the result of the expression right of the decimal point, and **scale** is a global variable that sets the precision of any operations, with exceptions. **scale** is initially **0**. **scale** cannot be negative. The max allowable value for **scale** is **BC_SCALE_MAX** and can be queried in bc(1) programs with the **maxscale()** built-in function. bc(1) has both *global* variables and *local* variables. All *local* variables are local to the function; they are parameters or are introduced in the **auto** list of a function (see the **FUNCTIONS** section). If a variable is accessed which is not a parameter or in the **auto** list, it is assumed to be *global*. If a parent function has a *local* variable version of a variable that a child function considers *global*, the value of that *global* variable in the child function is the value of the variable in the parent function, not the value of the actual *global* variable. All of the above applies to arrays as well. The value of a statement that is an expression (i.e., any of the named expressions or operands) is printed unless the lowest precedence operator is an assignment operator *and* the expression is notsurrounded by parentheses. The value that is printed is also assigned to the special variable **last**. A single dot (**.**) may also be used as a synonym for **last**. These are **non-portable extensions**. Either semicolons or newlines may separate statements. ## Comments There are two kinds of comments: 1. Block comments are enclosed in **/\*** and **\*/**. 2. Line comments go from **#** until, and not including, the next newline. This is a **non-portable extension**. ## Named Expressions The following are named expressions in bc(1): 1. Variables: **I** 2. Array Elements: **I[E]** 3. **ibase** 4. **obase** 5. **scale** 6. **last** or a single dot (**.**) Number 6 is a **non-portable extension**. Variables and arrays do not interfere; users can have arrays named the same as variables. This also applies to functions (see the **FUNCTIONS** section), so a user can have a variable, array, and function that all have the same name, and they will not shadow each other, whether inside of functions or not. Named expressions are required as the operand of **increment**/**decrement** operators and as the left side of **assignment** operators (see the *Operators* subsection). ## Operands The following are valid operands in bc(1): 1. Numbers (see the *Numbers* subsection below). 2. Array indices (**I[E]**). 3. **(E)**: The value of **E** (used to change precedence). 4. **sqrt(E)**: The square root of **E**. **E** must be non-negative. 5. **length(E)**: The number of significant decimal digits in **E**. Returns **1** for **0** with no decimal places. If given a string, the length of the string is returned. Passing a string to **length(E)** is a **non-portable extension**. 6. **length(I[])**: The number of elements in the array **I**. This is a **non-portable extension**. 7. **scale(E)**: The *scale* of **E**. 8. **abs(E)**: The absolute value of **E**. This is a **non-portable extension**. 9. **modexp(E, E, E)**: Modular exponentiation, where the first expression is the base, the second is the exponent, and the third is the modulus. All three values must be integers. The second argument must be non-negative. The third argument must be non-zero. This is a **non-portable extension**. 10. **divmod(E, E, I[])**: Division and modulus in one operation. This is for optimization. The first expression is the dividend, and the second is the divisor, which must be non-zero. The return value is the quotient, and the modulus is stored in index **0** of the provided array (the last argument). This is a **non-portable extension**. 11. **asciify(E)**: If **E** is a string, returns a string that is the first letter of its argument. If it is a number, calculates the number mod **256** and returns that number as a one-character string. This is a **non-portable extension**. 12. **I()**, **I(E)**, **I(E, E)**, and so on, where **I** is an identifier for a non-**void** function (see the *Void Functions* subsection of the **FUNCTIONS** section). The **E** argument(s) may also be arrays of the form **I[]**, which will automatically be turned into array references (see the *Array References* subsection of the **FUNCTIONS** section) if the corresponding parameter in the function definition is an array reference. 13. **read()**: Reads a line from **stdin** and uses that as an expression. The result of that expression is the result of the **read()** operand. This is a **non-portable extension**. 14. **maxibase()**: The max allowable **ibase**. This is a **non-portable extension**. 15. **maxobase()**: The max allowable **obase**. This is a **non-portable extension**. 16. **maxscale()**: The max allowable **scale**. This is a **non-portable extension**. 17. **line_length()**: The line length set with **BC_LINE_LENGTH** (see the **ENVIRONMENT VARIABLES** section). This is a **non-portable extension**. 18. **global_stacks()**: **0** if global stacks are not enabled with the **-g** or **-\-global-stacks** options, non-zero otherwise. See the **OPTIONS** section. This is a **non-portable extension**. 19. **leading_zero()**: **0** if leading zeroes are not enabled with the **-z** or **--leading-zeroes** options, non-zero otherwise. See the **OPTIONS** section. This is a **non-portable extension**. ## Numbers Numbers are strings made up of digits, uppercase letters, and at most **1** period for a radix. Numbers can have up to **BC_NUM_MAX** digits. Uppercase letters are equal to **9** + their position in the alphabet (i.e., **A** equals **10**, or **9+1**). If a digit or letter makes no sense with the current value of **ibase**, they are set to the value of the highest valid digit in **ibase**. Single-character numbers (i.e., **A** alone) take the value that they would have if they were valid digits, regardless of the value of **ibase**. This means that **A** alone always equals decimal **10** and **Z** alone always equals decimal **35**. ## Operators The following arithmetic and logical operators can be used. They are listed in order of decreasing precedence. Operators in the same group have the same precedence. **++** **-\-** : Type: Prefix and Postfix Associativity: None Description: **increment**, **decrement** **-** **!** : Type: Prefix Associativity: None Description: **negation**, **boolean not** **\^** : Type: Binary Associativity: Right Description: **power** **\*** **/** **%** : Type: Binary Associativity: Left Description: **multiply**, **divide**, **modulus** **+** **-** : Type: Binary Associativity: Left Description: **add**, **subtract** **=** **+=** **-=** **\*=** **/=** **%=** **\^=** : Type: Binary Associativity: Right Description: **assignment** **==** **\<=** **\>=** **!=** **\<** **\>** : Type: Binary Associativity: Left Description: **relational** **&&** : Type: Binary Associativity: Left Description: **boolean and** **||** : Type: Binary Associativity: Left Description: **boolean or** The operators will be described in more detail below. **++** **-\-** : The prefix and postfix **increment** and **decrement** operators behave exactly like they would in C. They require a named expression (see the *Named Expressions* subsection) as an operand. The prefix versions of these operators are more efficient; use them where possible. **-** : The **negation** operator returns **0** if a user attempts to negate any expression with the value **0**. Otherwise, a copy of the expression with its sign flipped is returned. **!** : The **boolean not** operator returns **1** if the expression is **0**, or **0** otherwise. This is a **non-portable extension**. **\^** : The **power** operator (not the **exclusive or** operator, as it would be in C) takes two expressions and raises the first to the power of the value of the second. The *scale* of the result is equal to **scale**. The second expression must be an integer (no *scale*), and if it is negative, the first value must be non-zero. **\*** : The **multiply** operator takes two expressions, multiplies them, and returns the product. If **a** is the *scale* of the first expression and **b** is the *scale* of the second expression, the *scale* of the result is equal to **min(a+b,max(scale,a,b))** where **min()** and **max()** return the obvious values. **/** : The **divide** operator takes two expressions, divides them, and returns the quotient. The *scale* of the result shall be the value of **scale**. The second expression must be non-zero. **%** : The **modulus** operator takes two expressions, **a** and **b**, and evaluates them by 1) Computing **a/b** to current **scale** and 2) Using the result of step 1 to calculate **a-(a/b)\*b** to *scale* **max(scale+scale(b),scale(a))**. The second expression must be non-zero. **+** : The **add** operator takes two expressions, **a** and **b**, and returns the sum, with a *scale* equal to the max of the *scale*s of **a** and **b**. **-** : The **subtract** operator takes two expressions, **a** and **b**, and returns the difference, with a *scale* equal to the max of the *scale*s of **a** and **b**. **=** **+=** **-=** **\*=** **/=** **%=** **\^=** : The **assignment** operators take two expressions, **a** and **b** where **a** is a named expression (see the *Named Expressions* subsection). For **=**, **b** is copied and the result is assigned to **a**. For all others, **a** and **b** are applied as operands to the corresponding arithmetic operator and the result is assigned to **a**. **==** **\<=** **\>=** **!=** **\<** **\>** : The **relational** operators compare two expressions, **a** and **b**, and if the relation holds, according to C language semantics, the result is **1**. Otherwise, it is **0**. Note that unlike in C, these operators have a lower precedence than the **assignment** operators, which means that **a=b\>c** is interpreted as **(a=b)\>c**. Also, unlike the [standard][1] requires, these operators can appear anywhere any other expressions can be used. This allowance is a **non-portable extension**. **&&** : The **boolean and** operator takes two expressions and returns **1** if both expressions are non-zero, **0** otherwise. This is *not* a short-circuit operator. This is a **non-portable extension**. **||** : The **boolean or** operator takes two expressions and returns **1** if one of the expressions is non-zero, **0** otherwise. This is *not* a short-circuit operator. This is a **non-portable extension**. ## Statements The following items are statements: 1. **E** 2. **{** **S** **;** ... **;** **S** **}** 3. **if** **(** **E** **)** **S** 4. **if** **(** **E** **)** **S** **else** **S** 5. **while** **(** **E** **)** **S** 6. **for** **(** **E** **;** **E** **;** **E** **)** **S** 7. An empty statement 8. **break** 9. **continue** 10. **quit** 11. **halt** 12. **limits** 13. A string of characters, enclosed in double quotes 14. **print** **E** **,** ... **,** **E** 15. **stream** **E** **,** ... **,** **E** 16. **I()**, **I(E)**, **I(E, E)**, and so on, where **I** is an identifier for a **void** function (see the *Void Functions* subsection of the **FUNCTIONS** section). The **E** argument(s) may also be arrays of the form **I[]**, which will automatically be turned into array references (see the *Array References* subsection of the **FUNCTIONS** section) if the corresponding parameter in the function definition is an array reference. Numbers 4, 9, 11, 12, 14, 15, and 16 are **non-portable extensions**. Also, as a **non-portable extension**, any or all of the expressions in the header of a for loop may be omitted. If the condition (second expression) is omitted, it is assumed to be a constant **1**. The **break** statement causes a loop to stop iterating and resume execution immediately following a loop. This is only allowed in loops. The **continue** statement causes a loop iteration to stop early and returns to the start of the loop, including testing the loop condition. This is only allowed in loops. The **if** **else** statement does the same thing as in C. The **quit** statement causes bc(1) to quit, even if it is on a branch that will not be executed (it is a compile-time command). The **halt** statement causes bc(1) to quit, if it is executed. (Unlike **quit** if it is on a branch of an **if** statement that is not executed, bc(1) does not quit.) The **limits** statement prints the limits that this bc(1) is subject to. This is like the **quit** statement in that it is a compile-time command. An expression by itself is evaluated and printed, followed by a newline. ## Strings If strings appear as a statement by themselves, they are printed without a trailing newline. In addition to appearing as a lone statement by themselves, strings can be assigned to variables and array elements. They can also be passed to functions in variable parameters. If any statement that expects a string is given a variable that had a string assigned to it, the statement acts as though it had received a string. If any math operation is attempted on a string or a variable or array element that has been assigned a string, an error is raised, and bc(1) resets (see the **RESET** section). Assigning strings to variables and array elements and passing them to functions are **non-portable extensions**. ## Print Statement The "expressions" in a **print** statement may also be strings. If they are, there are backslash escape sequences that are interpreted specially. What those sequences are, and what they cause to be printed, are shown below: **\\a**: **\\a** **\\b**: **\\b** **\\\\**: **\\** **\\e**: **\\** **\\f**: **\\f** **\\n**: **\\n** **\\q**: **"** **\\r**: **\\r** **\\t**: **\\t** Any other character following a backslash causes the backslash and character to be printed as-is. Any non-string expression in a print statement shall be assigned to **last**, like any other expression that is printed. ## Stream Statement The "expressions in a **stream** statement may also be strings. If a **stream** statement is given a string, it prints the string as though the string had appeared as its own statement. In other words, the **stream** statement prints strings normally, without a newline. If a **stream** statement is given a number, a copy of it is truncated and its absolute value is calculated. The result is then printed as though **obase** is **256** and each digit is interpreted as an 8-bit ASCII character, making it a byte stream. ## Order of Evaluation All expressions in a statment are evaluated left to right, except as necessary to maintain order of operations. This means, for example, assuming that **i** is equal to **0**, in the expression a[i++] = i++ the first (or 0th) element of **a** is set to **1**, and **i** is equal to **2** at the end of the expression. This includes function arguments. Thus, assuming **i** is equal to **0**, this means that in the expression x(i++, i++) the first argument passed to **x()** is **0**, and the second argument is **1**, while **i** is equal to **2** before the function starts executing. # FUNCTIONS Function definitions are as follows: ``` define I(I,...,I){ auto I,...,I S;...;S return(E) } ``` Any **I** in the parameter list or **auto** list may be replaced with **I[]** to make a parameter or **auto** var an array, and any **I** in the parameter list may be replaced with **\*I[]** to make a parameter an array reference. Callers of functions that take array references should not put an asterisk in the call; they must be called with just **I[]** like normal array parameters and will be automatically converted into references. As a **non-portable extension**, the opening brace of a **define** statement may appear on the next line. As a **non-portable extension**, the return statement may also be in one of the following forms: 1. **return** 2. **return** **(** **)** 3. **return** **E** The first two, or not specifying a **return** statement, is equivalent to **return (0)**, unless the function is a **void** function (see the *Void Functions* subsection below). ## Void Functions Functions can also be **void** functions, defined as follows: ``` define void I(I,...,I){ auto I,...,I S;...;S return } ``` They can only be used as standalone expressions, where such an expression would be printed alone, except in a print statement. Void functions can only use the first two **return** statements listed above. They can also omit the return statement entirely. The word "void" is not treated as a keyword; it is still possible to have variables, arrays, and functions named **void**. The word "void" is only treated specially right after the **define** keyword. This is a **non-portable extension**. ## Array References For any array in the parameter list, if the array is declared in the form ``` *I[] ``` it is a **reference**. Any changes to the array in the function are reflected, when the function returns, to the array that was passed in. Other than this, all function arguments are passed by value. This is a **non-portable extension**. # LIBRARY All of the functions below are available when the **-l** or **-\-mathlib** command-line flags are given. ## Standard Library The [standard][1] defines the following functions for the math library: **s(x)** : Returns the sine of **x**, which is assumed to be in radians. This is a transcendental function (see the *Transcendental Functions* subsection below). **c(x)** : Returns the cosine of **x**, which is assumed to be in radians. This is a transcendental function (see the *Transcendental Functions* subsection below). **a(x)** : Returns the arctangent of **x**, in radians. This is a transcendental function (see the *Transcendental Functions* subsection below). **l(x)** : Returns the natural logarithm of **x**. This is a transcendental function (see the *Transcendental Functions* subsection below). **e(x)** : Returns the mathematical constant **e** raised to the power of **x**. This is a transcendental function (see the *Transcendental Functions* subsection below). **j(x, n)** : Returns the bessel integer order **n** (truncated) of **x**. This is a transcendental function (see the *Transcendental Functions* subsection below). ## Transcendental Functions All transcendental functions can return slightly inaccurate results (up to 1 [ULP][4]). This is unavoidable, and [this article][5] explains why it is impossible and unnecessary to calculate exact results for the transcendental functions. Because of the possible inaccuracy, I recommend that users call those functions with the precision (**scale**) set to at least 1 higher than is necessary. If exact results are *absolutely* required, users can double the precision (**scale**) and then truncate. The transcendental functions in the standard math library are: * **s(x)** * **c(x)** * **a(x)** * **l(x)** * **e(x)** * **j(x, n)** # RESET When bc(1) encounters an error or a signal that it has a non-default handler for, it resets. This means that several things happen. First, any functions that are executing are stopped and popped off the stack. The behavior is not unlike that of exceptions in programming languages. Then the execution point is set so that any code waiting to execute (after all functions returned) is skipped. Thus, when bc(1) resets, it skips any remaining code waiting to be executed. Then, if it is interactive mode, and the error was not a fatal error (see the **EXIT STATUS** section), it asks for more input; otherwise, it exits with the appropriate return code. Note that this reset behavior is different from the GNU bc(1), which attempts to start executing the statement right after the one that caused an error. # PERFORMANCE Most bc(1) implementations use **char** types to calculate the value of **1** decimal digit at a time, but that can be slow. This bc(1) does something different. It uses large integers to calculate more than **1** decimal digit at a time. If built in a environment where **BC_LONG_BIT** (see the **LIMITS** section) is **64**, then each integer has **9** decimal digits. If built in an environment where **BC_LONG_BIT** is **32** then each integer has **4** decimal digits. This value (the number of decimal digits per large integer) is called **BC_BASE_DIGS**. The actual values of **BC_LONG_BIT** and **BC_BASE_DIGS** can be queried with the **limits** statement. In addition, this bc(1) uses an even larger integer for overflow checking. This integer type depends on the value of **BC_LONG_BIT**, but is always at least twice as large as the integer type used to store digits. # LIMITS The following are the limits on bc(1): **BC_LONG_BIT** : The number of bits in the **long** type in the environment where bc(1) was built. This determines how many decimal digits can be stored in a single large integer (see the **PERFORMANCE** section). **BC_BASE_DIGS** : The number of decimal digits per large integer (see the **PERFORMANCE** section). Depends on **BC_LONG_BIT**. **BC_BASE_POW** : The max decimal number that each large integer can store (see **BC_BASE_DIGS**) plus **1**. Depends on **BC_BASE_DIGS**. **BC_OVERFLOW_MAX** : The max number that the overflow type (see the **PERFORMANCE** section) can hold. Depends on **BC_LONG_BIT**. **BC_BASE_MAX** : The maximum output base. Set at **BC_BASE_POW**. **BC_DIM_MAX** : The maximum size of arrays. Set at **SIZE_MAX-1**. **BC_SCALE_MAX** : The maximum **scale**. Set at **BC_OVERFLOW_MAX-1**. **BC_STRING_MAX** : The maximum length of strings. Set at **BC_OVERFLOW_MAX-1**. **BC_NAME_MAX** : The maximum length of identifiers. Set at **BC_OVERFLOW_MAX-1**. **BC_NUM_MAX** : The maximum length of a number (in decimal digits), which includes digits after the decimal point. Set at **BC_OVERFLOW_MAX-1**. Exponent : The maximum allowable exponent (positive or negative). Set at **BC_OVERFLOW_MAX**. Number of vars : The maximum number of vars/arrays. Set at **SIZE_MAX-1**. The actual values can be queried with the **limits** statement. These limits are meant to be effectively non-existent; the limits are so large (at least on 64-bit machines) that there should not be any point at which they become a problem. In fact, memory should be exhausted before these limits should be hit. # ENVIRONMENT VARIABLES bc(1) recognizes the following environment variables: **POSIXLY_CORRECT** : If this variable exists (no matter the contents), bc(1) behaves as if the **-s** option was given. **BC_ENV_ARGS** : This is another way to give command-line arguments to bc(1). They should be in the same format as all other command-line arguments. These are always processed first, so any files given in **BC_ENV_ARGS** will be processed before arguments and files given on the command-line. This gives the user the ability to set up "standard" options and files to be used at every invocation. The most useful thing for such files to contain would be useful functions that the user might want every time bc(1) runs. The code that parses **BC_ENV_ARGS** will correctly handle quoted arguments, but it does not understand escape sequences. For example, the string **"/home/gavin/some bc file.bc"** will be correctly parsed, but the string **"/home/gavin/some \"bc\" file.bc"** will include the backslashes. The quote parsing will handle either kind of quotes, **'** or **"**. Thus, if you have a file with any number of single quotes in the name, you can use double quotes as the outside quotes, as in **"some 'bc' file.bc"**, and vice versa if you have a file with double quotes. However, handling a file with both kinds of quotes in **BC_ENV_ARGS** is not supported due to the complexity of the parsing, though such files are still supported on the command-line where the parsing is done by the shell. **BC_LINE_LENGTH** : If this environment variable exists and contains an integer that is greater than **1** and is less than **UINT16_MAX** (**2\^16-1**), bc(1) will output lines to that length, including the backslash (**\\**). The default line length is **70**. The special value of **0** will disable line length checking and print numbers without regard to line length and without backslashes and newlines. **BC_BANNER** : If this environment variable exists and contains an integer, then a non-zero value activates the copyright banner when bc(1) is in interactive mode, while zero deactivates it. If bc(1) is not in interactive mode (see the **INTERACTIVE MODE** section), then this environment variable has no effect because bc(1) does not print the banner when not in interactive mode. This environment variable overrides the default, which can be queried with the **-h** or **-\-help** options. **BC_SIGINT_RESET** : If bc(1) is not in interactive mode (see the **INTERACTIVE MODE** section), then this environment variable has no effect because bc(1) exits on **SIGINT** when not in interactive mode. However, when bc(1) is in interactive mode, then if this environment variable exists and contains an integer, a non-zero value makes bc(1) reset on **SIGINT**, rather than exit, and zero makes bc(1) exit. If this environment variable exists and is *not* an integer, then bc(1) will exit on **SIGINT**. This environment variable overrides the default, which can be queried with the **-h** or **-\-help** options. **BC_TTY_MODE** : If TTY mode is *not* available (see the **TTY MODE** section), then this environment variable has no effect. However, when TTY mode is available, then if this environment variable exists and contains an integer, then a non-zero value makes bc(1) use TTY mode, and zero makes bc(1) not use TTY mode. This environment variable overrides the default, which can be queried with the **-h** or **-\-help** options. **BC_PROMPT** : If TTY mode is *not* available (see the **TTY MODE** section), then this environment variable has no effect. However, when TTY mode is available, then if this environment variable exists and contains an integer, a non-zero value makes bc(1) use a prompt, and zero or a non-integer makes bc(1) not use a prompt. If this environment variable does not exist and **BC_TTY_MODE** does, then the value of the **BC_TTY_MODE** environment variable is used. This environment variable and the **BC_TTY_MODE** environment variable override the default, which can be queried with the **-h** or **-\-help** options. +**BC_EXPR_EXIT** + +: If any expressions or expression files are given on the command-line with + **-e**, **-\-expression**, **-f**, or **-\-file**, then if this environment + variable exists and contains an integer, a non-zero value makes bc(1) exit + after executing the expressions and expression files, and a non-zero value + makes bc(1) not exit. + + This environment variable overrides the default, which can be queried with + the **-h** or **-\-help** options. + # EXIT STATUS bc(1) returns the following exit statuses: **0** : No error. **1** : A math error occurred. This follows standard practice of using **1** for expected errors, since math errors will happen in the process of normal execution. Math errors include divide by **0**, taking the square root of a negative number, attempting to convert a negative number to a hardware integer, overflow when converting a number to a hardware integer, overflow when calculating the size of a number, and attempting to use a non-integer where an integer is required. Converting to a hardware integer happens for the second operand of the power (**\^**) operator and the corresponding assignment operator. **2** : A parse error occurred. Parse errors include unexpected **EOF**, using an invalid character, failing to find the end of a string or comment, using a token where it is invalid, giving an invalid expression, giving an invalid print statement, giving an invalid function definition, attempting to assign to an expression that is not a named expression (see the *Named Expressions* subsection of the **SYNTAX** section), giving an invalid **auto** list, having a duplicate **auto**/function parameter, failing to find the end of a code block, attempting to return a value from a **void** function, attempting to use a variable as a reference, and using any extensions when the option **-s** or any equivalents were given. **3** : A runtime error occurred. Runtime errors include assigning an invalid number to any global (**ibase**, **obase**, or **scale**), giving a bad expression to a **read()** call, calling **read()** inside of a **read()** call, type errors, passing the wrong number of arguments to functions, attempting to call an undefined function, and attempting to use a **void** function call as a value in an expression. **4** : A fatal error occurred. Fatal errors include memory allocation errors, I/O errors, failing to open files, attempting to use files that do not have only ASCII characters (bc(1) only accepts ASCII characters), attempting to open a directory as a file, and giving invalid command-line options. The exit status **4** is special; when a fatal error occurs, bc(1) always exits and returns **4**, no matter what mode bc(1) is in. The other statuses will only be returned when bc(1) is not in interactive mode (see the **INTERACTIVE MODE** section), since bc(1) resets its state (see the **RESET** section) and accepts more input when one of those errors occurs in interactive mode. This is also the case when interactive mode is forced by the **-i** flag or **-\-interactive** option. These exit statuses allow bc(1) to be used in shell scripting with error checking, and its normal behavior can be forced by using the **-i** flag or **-\-interactive** option. # INTERACTIVE MODE Per the [standard][1], bc(1) has an interactive mode and a non-interactive mode. Interactive mode is turned on automatically when both **stdin** and **stdout** are hooked to a terminal, but the **-i** flag and **-\-interactive** option can turn it on in other situations. In interactive mode, bc(1) attempts to recover from errors (see the **RESET** section), and in normal execution, flushes **stdout** as soon as execution is done for the current input. bc(1) may also reset on **SIGINT** instead of exit, depending on the contents of, or default for, the **BC_SIGINT_RESET** environment variable (see the **ENVIRONMENT VARIABLES** section). # TTY MODE If **stdin**, **stdout**, and **stderr** are all connected to a TTY, then "TTY mode" is considered to be available, and thus, bc(1) can turn on TTY mode, subject to some settings. If there is the environment variable **BC_TTY_MODE** in the environment (see the **ENVIRONMENT VARIABLES** section), then if that environment variable contains a non-zero integer, bc(1) will turn on TTY mode when **stdin**, **stdout**, and **stderr** are all connected to a TTY. If the **BC_TTY_MODE** environment variable exists but is *not* a non-zero integer, then bc(1) will not turn TTY mode on. If the environment variable **BC_TTY_MODE** does *not* exist, the default setting is used. The default setting can be queried with the **-h** or **-\-help** options. TTY mode is different from interactive mode because interactive mode is required in the [bc(1) specification][1], and interactive mode requires only **stdin** and **stdout** to be connected to a terminal. ## Prompt If TTY mode is available, then a prompt can be enabled. Like TTY mode itself, it can be turned on or off with an environment variable: **BC_PROMPT** (see the **ENVIRONMENT VARIABLES** section). If the environment variable **BC_PROMPT** exists and is a non-zero integer, then the prompt is turned on when **stdin**, **stdout**, and **stderr** are connected to a TTY and the **-P** and **-\-no-prompt** options were not used. The read prompt will be turned on under the same conditions, except that the **-R** and **-\-no-read-prompt** options must also not be used. However, if **BC_PROMPT** does not exist, the prompt can be enabled or disabled with the **BC_TTY_MODE** environment variable, the **-P** and **-\-no-prompt** options, and the **-R** and **-\-no-read-prompt** options. See the **ENVIRONMENT VARIABLES** and **OPTIONS** sections for more details. # SIGNAL HANDLING Sending a **SIGINT** will cause bc(1) to do one of two things. If bc(1) is not in interactive mode (see the **INTERACTIVE MODE** section), or the **BC_SIGINT_RESET** environment variable (see the **ENVIRONMENT VARIABLES** section), or its default, is either not an integer or it is zero, bc(1) will exit. However, if bc(1) is in interactive mode, and the **BC_SIGINT_RESET** or its default is an integer and non-zero, then bc(1) will stop executing the current input and reset (see the **RESET** section) upon receiving a **SIGINT**. Note that "current input" can mean one of two things. If bc(1) is processing input from **stdin** in interactive mode, it will ask for more input. If bc(1) is processing input from a file in interactive mode, it will stop processing the file and start processing the next file, if one exists, or ask for input from **stdin** if no other file exists. This means that if a **SIGINT** is sent to bc(1) as it is executing a file, it can seem as though bc(1) did not respond to the signal since it will immediately start executing the next file. This is by design; most files that users execute when interacting with bc(1) have function definitions, which are quick to parse. If a file takes a long time to execute, there may be a bug in that file. The rest of the files could still be executed without problem, allowing the user to continue. **SIGTERM** and **SIGQUIT** cause bc(1) to clean up and exit, and it uses the default handler for all other signals. # LOCALES This bc(1) ships with support for adding error messages for different locales and thus, supports **LC_MESSAGES**. # SEE ALSO dc(1) # STANDARDS bc(1) is compliant with the [IEEE Std 1003.1-2017 (“POSIX.1-2017”)][1] specification. The flags **-efghiqsvVw**, all long options, and the extensions noted above are extensions to that specification. Note that the specification explicitly says that bc(1) only accepts numbers that use a period (**.**) as a radix point, regardless of the value of **LC_NUMERIC**. This bc(1) supports error messages for different locales, and thus, it supports **LC_MESSAGES**. # BUGS None are known. Report bugs at https://git.yzena.com/gavin/bc. # AUTHORS Gavin D. Howard and contributors. [1]: https://pubs.opengroup.org/onlinepubs/9699919799/utilities/bc.html [2]: https://www.gnu.org/software/bc/ [3]: https://en.wikipedia.org/wiki/Rounding#Round_half_away_from_zero [4]: https://en.wikipedia.org/wiki/Unit_in_the_last_place [5]: https://people.eecs.berkeley.edu/~wkahan/LOG10HAF.TXT [6]: https://en.wikipedia.org/wiki/Rounding#Rounding_away_from_zero diff --git a/contrib/bc/manuals/bc/EHN.1 b/contrib/bc/manuals/bc/EHN.1 index f0519898ad7e..6b49f3651d5a 100644 --- a/contrib/bc/manuals/bc/EHN.1 +++ b/contrib/bc/manuals/bc/EHN.1 @@ -1,1594 +1,1607 @@ .\" .\" SPDX-License-Identifier: BSD-2-Clause .\" .\" Copyright (c) 2018-2021 Gavin D. Howard and contributors. .\" .\" Redistribution and use in source and binary forms, with or without .\" modification, are permitted provided that the following conditions are met: .\" .\" * Redistributions of source code must retain the above copyright notice, .\" this list of conditions and the following disclaimer. .\" .\" * Redistributions in binary form must reproduce the above copyright notice, .\" this list of conditions and the following disclaimer in the documentation .\" and/or other materials provided with the distribution. .\" .\" THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" .\" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE .\" IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE .\" ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE .\" LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR .\" CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF .\" SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS .\" INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN .\" CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) .\" ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE .\" POSSIBILITY OF SUCH DAMAGE. .\" .TH "BC" "1" "June 2021" "Gavin D. Howard" "General Commands Manual" .SH NAME .PP bc - arbitrary-precision decimal arithmetic language and calculator .SH SYNOPSIS .PP \f[B]bc\f[R] [\f[B]-ghilPqRsvVw\f[R]] [\f[B]--global-stacks\f[R]] [\f[B]--help\f[R]] [\f[B]--interactive\f[R]] [\f[B]--mathlib\f[R]] [\f[B]--no-prompt\f[R]] [\f[B]--no-read-prompt\f[R]] [\f[B]--quiet\f[R]] [\f[B]--standard\f[R]] [\f[B]--warn\f[R]] [\f[B]--version\f[R]] [\f[B]-e\f[R] \f[I]expr\f[R]] [\f[B]--expression\f[R]=\f[I]expr\f[R]\&...] [\f[B]-f\f[R] \f[I]file\f[R]\&...] [\f[B]--file\f[R]=\f[I]file\f[R]\&...] [\f[I]file\f[R]\&...] .SH DESCRIPTION .PP bc(1) is an interactive processor for a language first standardized in 1991 by POSIX. (The current standard is here (https://pubs.opengroup.org/onlinepubs/9699919799/utilities/bc.html).) The language provides unlimited precision decimal arithmetic and is somewhat C-like, but there are differences. Such differences will be noted in this document. .PP After parsing and handling options, this bc(1) reads any files given on the command line and executes them before reading from \f[B]stdin\f[R]. .PP This bc(1) is a drop-in replacement for \f[I]any\f[R] bc(1), including (and especially) the GNU bc(1). .PP \f[B]Note\f[R]: If running this bc(1) on \f[I]any\f[R] script meant for another bc(1) gives a parse error, it is probably because a word this bc(1) reserves as a keyword is used as the name of a function, variable, or array. To fix that, use the command-line option \f[B]-r\f[R] \f[I]keyword\f[R], where \f[I]keyword\f[R] is the keyword that is used as a name in the script. For more information, see the \f[B]OPTIONS\f[R] section. .PP If parsing scripts meant for other bc(1) implementations still does not work, that is a bug and should be reported. See the \f[B]BUGS\f[R] section. .SH OPTIONS .PP The following are the options that bc(1) accepts. .TP \f[B]-g\f[R], \f[B]--global-stacks\f[R] Turns the globals \f[B]ibase\f[R], \f[B]obase\f[R], and \f[B]scale\f[R] into stacks. .RS .PP This has the effect that a copy of the current value of all three are pushed onto a stack for every function call, as well as popped when every function returns. This means that functions can assign to any and all of those globals without worrying that the change will affect other functions. Thus, a hypothetical function named \f[B]output(x,b)\f[R] that simply printed \f[B]x\f[R] in base \f[B]b\f[R] could be written like this: .IP .nf \f[C] define void output(x, b) { obase=b x } \f[R] .fi .PP instead of like this: .IP .nf \f[C] define void output(x, b) { auto c c=obase obase=b x obase=c } \f[R] .fi .PP This makes writing functions much easier. .PP However, since using this flag means that functions cannot set \f[B]ibase\f[R], \f[B]obase\f[R], or \f[B]scale\f[R] globally, functions that are made to do so cannot work anymore. There are two possible use cases for that, and each has a solution. .PP First, if a function is called on startup to turn bc(1) into a number converter, it is possible to replace that capability with various shell aliases. Examples: .IP .nf \f[C] alias d2o=\[dq]bc -e ibase=A -e obase=8\[dq] alias h2b=\[dq]bc -e ibase=G -e obase=2\[dq] \f[R] .fi .PP Second, if the purpose of a function is to set \f[B]ibase\f[R], \f[B]obase\f[R], or \f[B]scale\f[R] globally for any other purpose, it could be split into one to three functions (based on how many globals it sets) and each of those functions could return the desired value for a global. .PP If the behavior of this option is desired for every run of bc(1), then users could make sure to define \f[B]BC_ENV_ARGS\f[R] and include this option (see the \f[B]ENVIRONMENT VARIABLES\f[R] section for more details). .PP If \f[B]-s\f[R], \f[B]-w\f[R], or any equivalents are used, this option is ignored. .PP This is a \f[B]non-portable extension\f[R]. .RE .TP \f[B]-h\f[R], \f[B]--help\f[R] Prints a usage message and quits. .TP \f[B]-i\f[R], \f[B]--interactive\f[R] Forces interactive mode. (See the \f[B]INTERACTIVE MODE\f[R] section.) .RS .PP This is a \f[B]non-portable extension\f[R]. .RE .TP \f[B]-L\f[R], \f[B]--no-line-length\f[R] Disables line length checking and prints numbers without backslashes and newlines. In other words, this option sets \f[B]BC_LINE_LENGTH\f[R] to \f[B]0\f[R] (see the \f[B]ENVIRONMENT VARIABLES\f[R] section). .RS .PP This is a \f[B]non-portable extension\f[R]. .RE .TP \f[B]-l\f[R], \f[B]--mathlib\f[R] Sets \f[B]scale\f[R] (see the \f[B]SYNTAX\f[R] section) to \f[B]20\f[R] and loads the included math library before running any code, including any expressions or files specified on the command line. .RS .PP To learn what is in the library, see the \f[B]LIBRARY\f[R] section. .RE .TP \f[B]-P\f[R], \f[B]--no-prompt\f[R] Disables the prompt in TTY mode. (The prompt is only enabled in TTY mode. See the \f[B]TTY MODE\f[R] section.) This is mostly for those users that do not want a prompt or are not used to having them in bc(1). Most of those users would want to put this option in \f[B]BC_ENV_ARGS\f[R] (see the \f[B]ENVIRONMENT VARIABLES\f[R] section). .RS .PP These options override the \f[B]BC_PROMPT\f[R] and \f[B]BC_TTY_MODE\f[R] environment variables (see the \f[B]ENVIRONMENT VARIABLES\f[R] section). .PP This is a \f[B]non-portable extension\f[R]. .RE .TP \f[B]-R\f[R], \f[B]--no-read-prompt\f[R] Disables the read prompt in TTY mode. (The read prompt is only enabled in TTY mode. See the \f[B]TTY MODE\f[R] section.) This is mostly for those users that do not want a read prompt or are not used to having them in bc(1). Most of those users would want to put this option in \f[B]BC_ENV_ARGS\f[R] (see the \f[B]ENVIRONMENT VARIABLES\f[R] section). This option is also useful in hash bang lines of bc(1) scripts that prompt for user input. .RS .PP This option does not disable the regular prompt because the read prompt is only used when the \f[B]read()\f[R] built-in function is called. .PP These options \f[I]do\f[R] override the \f[B]BC_PROMPT\f[R] and \f[B]BC_TTY_MODE\f[R] environment variables (see the \f[B]ENVIRONMENT VARIABLES\f[R] section), but only for the read prompt. .PP This is a \f[B]non-portable extension\f[R]. .RE .TP \f[B]-r\f[R] \f[I]keyword\f[R], \f[B]--redefine\f[R]=\f[I]keyword\f[R] Redefines \f[I]keyword\f[R] in order to allow it to be used as a function, variable, or array name. This is useful when this bc(1) gives parse errors when parsing scripts meant for other bc(1) implementations. .RS .PP The keywords this bc(1) allows to be redefined are: .IP \[bu] 2 \f[B]abs\f[R] .IP \[bu] 2 \f[B]asciify\f[R] .IP \[bu] 2 \f[B]continue\f[R] .IP \[bu] 2 \f[B]divmod\f[R] .IP \[bu] 2 \f[B]else\f[R] .IP \[bu] 2 \f[B]halt\f[R] .IP \[bu] 2 \f[B]last\f[R] .IP \[bu] 2 \f[B]limits\f[R] .IP \[bu] 2 \f[B]maxibase\f[R] .IP \[bu] 2 \f[B]maxobase\f[R] .IP \[bu] 2 \f[B]maxscale\f[R] .IP \[bu] 2 \f[B]modexp\f[R] .IP \[bu] 2 \f[B]print\f[R] .IP \[bu] 2 \f[B]read\f[R] .IP \[bu] 2 \f[B]stream\f[R] .PP If any of those keywords are used as a function, variable, or array name in a script, use this option with the keyword as the argument. If multiple are used, use this option for all of them; it can be used multiple times. .PP Keywords are \f[I]not\f[R] redefined when parsing the builtin math library (see the \f[B]LIBRARY\f[R] section). .PP It is a fatal error to redefine keywords mandated by the POSIX standard. It is a fatal error to attempt to redefine words that this bc(1) does not reserve as keywords. .RE .TP \f[B]-q\f[R], \f[B]--quiet\f[R] This option is for compatibility with the GNU bc(1) (https://www.gnu.org/software/bc/); it is a no-op. Without this option, GNU bc(1) prints a copyright header. This bc(1) only prints the copyright header if one or more of the \f[B]-v\f[R], \f[B]-V\f[R], or \f[B]--version\f[R] options are given. .RS .PP This is a \f[B]non-portable extension\f[R]. .RE .TP \f[B]-s\f[R], \f[B]--standard\f[R] Process exactly the language defined by the standard (https://pubs.opengroup.org/onlinepubs/9699919799/utilities/bc.html) and error if any extensions are used. .RS .PP This is a \f[B]non-portable extension\f[R]. .RE .TP \f[B]-v\f[R], \f[B]-V\f[R], \f[B]--version\f[R] Print the version information (copyright header) and exit. .RS .PP This is a \f[B]non-portable extension\f[R]. .RE .TP \f[B]-w\f[R], \f[B]--warn\f[R] Like \f[B]-s\f[R] and \f[B]--standard\f[R], except that warnings (and not errors) are printed for non-standard extensions and execution continues normally. .RS .PP This is a \f[B]non-portable extension\f[R]. .RE .TP \f[B]-z\f[R], \f[B]--leading-zeroes\f[R] Makes bc(1) print all numbers greater than \f[B]-1\f[R] and less than \f[B]1\f[R], and not equal to \f[B]0\f[R], with a leading zero. .RS .PP This can be set for individual numbers with the \f[B]plz(x)\f[R], plznl(x)**, \f[B]pnlz(x)\f[R], and \f[B]pnlznl(x)\f[R] functions in the extended math library (see the \f[B]LIBRARY\f[R] section). .PP This is a \f[B]non-portable extension\f[R]. .RE .TP \f[B]-e\f[R] \f[I]expr\f[R], \f[B]--expression\f[R]=\f[I]expr\f[R] Evaluates \f[I]expr\f[R]. If multiple expressions are given, they are evaluated in order. If files are given as well (see below), the expressions and files are evaluated in the order given. This means that if a file is given before an expression, the file is read in and evaluated first. .RS .PP If this option is given on the command-line (i.e., not in \f[B]BC_ENV_ARGS\f[R], see the \f[B]ENVIRONMENT VARIABLES\f[R] section), then after processing all expressions and files, bc(1) will exit, unless \f[B]-\f[R] (\f[B]stdin\f[R]) was given as an argument at least once to \f[B]-f\f[R] or \f[B]--file\f[R], whether on the command-line or in \f[B]BC_ENV_ARGS\f[R]. However, if any other \f[B]-e\f[R], \f[B]--expression\f[R], \f[B]-f\f[R], or \f[B]--file\f[R] arguments are given after \f[B]-f-\f[R] or equivalent is given, bc(1) will give a fatal error and exit. .PP This is a \f[B]non-portable extension\f[R]. .RE .TP \f[B]-f\f[R] \f[I]file\f[R], \f[B]--file\f[R]=\f[I]file\f[R] Reads in \f[I]file\f[R] and evaluates it, line by line, as though it were read through \f[B]stdin\f[R]. If expressions are also given (see above), the expressions are evaluated in the order given. .RS .PP If this option is given on the command-line (i.e., not in \f[B]BC_ENV_ARGS\f[R], see the \f[B]ENVIRONMENT VARIABLES\f[R] section), then after processing all expressions and files, bc(1) will exit, unless \f[B]-\f[R] (\f[B]stdin\f[R]) was given as an argument at least once to \f[B]-f\f[R] or \f[B]--file\f[R]. However, if any other \f[B]-e\f[R], \f[B]--expression\f[R], \f[B]-f\f[R], or \f[B]--file\f[R] arguments are given after \f[B]-f-\f[R] or equivalent is given, bc(1) will give a fatal error and exit. .PP This is a \f[B]non-portable extension\f[R]. .RE .PP All long options are \f[B]non-portable extensions\f[R]. .SH STDIN .PP If no files or expressions are given by the \f[B]-f\f[R], \f[B]--file\f[R], \f[B]-e\f[R], or \f[B]--expression\f[R] options, then bc(1) read from \f[B]stdin\f[R]. .PP However, there are a few caveats to this. .PP First, \f[B]stdin\f[R] is evaluated a line at a time. The only exception to this is if the parse cannot complete. That means that starting a string without ending it or starting a function, \f[B]if\f[R] statement, or loop without ending it will also cause bc(1) to not execute. .PP Second, after an \f[B]if\f[R] statement, bc(1) doesn\[cq]t know if an \f[B]else\f[R] statement will follow, so it will not execute until it knows there will not be an \f[B]else\f[R] statement. .SH STDOUT .PP Any non-error output is written to \f[B]stdout\f[R]. In addition, if history (see the \f[B]HISTORY\f[R] section) and the prompt (see the \f[B]TTY MODE\f[R] section) are enabled, both are output to \f[B]stdout\f[R]. .PP \f[B]Note\f[R]: Unlike other bc(1) implementations, this bc(1) will issue a fatal error (see the \f[B]EXIT STATUS\f[R] section) if it cannot write to \f[B]stdout\f[R], so if \f[B]stdout\f[R] is closed, as in \f[B]bc >&-\f[R], it will quit with an error. This is done so that bc(1) can report problems when \f[B]stdout\f[R] is redirected to a file. .PP If there are scripts that depend on the behavior of other bc(1) implementations, it is recommended that those scripts be changed to redirect \f[B]stdout\f[R] to \f[B]/dev/null\f[R]. .SH STDERR .PP Any error output is written to \f[B]stderr\f[R]. .PP \f[B]Note\f[R]: Unlike other bc(1) implementations, this bc(1) will issue a fatal error (see the \f[B]EXIT STATUS\f[R] section) if it cannot write to \f[B]stderr\f[R], so if \f[B]stderr\f[R] is closed, as in \f[B]bc 2>&-\f[R], it will quit with an error. This is done so that bc(1) can exit with an error code when \f[B]stderr\f[R] is redirected to a file. .PP If there are scripts that depend on the behavior of other bc(1) implementations, it is recommended that those scripts be changed to redirect \f[B]stderr\f[R] to \f[B]/dev/null\f[R]. .SH SYNTAX .PP The syntax for bc(1) programs is mostly C-like, with some differences. This bc(1) follows the POSIX standard (https://pubs.opengroup.org/onlinepubs/9699919799/utilities/bc.html), which is a much more thorough resource for the language this bc(1) accepts. This section is meant to be a summary and a listing of all the extensions to the standard. .PP In the sections below, \f[B]E\f[R] means expression, \f[B]S\f[R] means statement, and \f[B]I\f[R] means identifier. .PP Identifiers (\f[B]I\f[R]) start with a lowercase letter and can be followed by any number (up to \f[B]BC_NAME_MAX-1\f[R]) of lowercase letters (\f[B]a-z\f[R]), digits (\f[B]0-9\f[R]), and underscores (\f[B]_\f[R]). The regex is \f[B][a-z][a-z0-9_]*\f[R]. Identifiers with more than one character (letter) are a \f[B]non-portable extension\f[R]. .PP \f[B]ibase\f[R] is a global variable determining how to interpret constant numbers. It is the \[lq]input\[rq] base, or the number base used for interpreting input numbers. \f[B]ibase\f[R] is initially \f[B]10\f[R]. If the \f[B]-s\f[R] (\f[B]--standard\f[R]) and \f[B]-w\f[R] (\f[B]--warn\f[R]) flags were not given on the command line, the max allowable value for \f[B]ibase\f[R] is \f[B]36\f[R]. Otherwise, it is \f[B]16\f[R]. The min allowable value for \f[B]ibase\f[R] is \f[B]2\f[R]. The max allowable value for \f[B]ibase\f[R] can be queried in bc(1) programs with the \f[B]maxibase()\f[R] built-in function. .PP \f[B]obase\f[R] is a global variable determining how to output results. It is the \[lq]output\[rq] base, or the number base used for outputting numbers. \f[B]obase\f[R] is initially \f[B]10\f[R]. The max allowable value for \f[B]obase\f[R] is \f[B]BC_BASE_MAX\f[R] and can be queried in bc(1) programs with the \f[B]maxobase()\f[R] built-in function. The min allowable value for \f[B]obase\f[R] is \f[B]2\f[R]. Values are output in the specified base. .PP The \f[I]scale\f[R] of an expression is the number of digits in the result of the expression right of the decimal point, and \f[B]scale\f[R] is a global variable that sets the precision of any operations, with exceptions. \f[B]scale\f[R] is initially \f[B]0\f[R]. \f[B]scale\f[R] cannot be negative. The max allowable value for \f[B]scale\f[R] is \f[B]BC_SCALE_MAX\f[R] and can be queried in bc(1) programs with the \f[B]maxscale()\f[R] built-in function. .PP bc(1) has both \f[I]global\f[R] variables and \f[I]local\f[R] variables. All \f[I]local\f[R] variables are local to the function; they are parameters or are introduced in the \f[B]auto\f[R] list of a function (see the \f[B]FUNCTIONS\f[R] section). If a variable is accessed which is not a parameter or in the \f[B]auto\f[R] list, it is assumed to be \f[I]global\f[R]. If a parent function has a \f[I]local\f[R] variable version of a variable that a child function considers \f[I]global\f[R], the value of that \f[I]global\f[R] variable in the child function is the value of the variable in the parent function, not the value of the actual \f[I]global\f[R] variable. .PP All of the above applies to arrays as well. .PP The value of a statement that is an expression (i.e., any of the named expressions or operands) is printed unless the lowest precedence operator is an assignment operator \f[I]and\f[R] the expression is notsurrounded by parentheses. .PP The value that is printed is also assigned to the special variable \f[B]last\f[R]. A single dot (\f[B].\f[R]) may also be used as a synonym for \f[B]last\f[R]. These are \f[B]non-portable extensions\f[R]. .PP Either semicolons or newlines may separate statements. .SS Comments .PP There are two kinds of comments: .IP "1." 3 Block comments are enclosed in \f[B]/*\f[R] and \f[B]*/\f[R]. .IP "2." 3 Line comments go from \f[B]#\f[R] until, and not including, the next newline. This is a \f[B]non-portable extension\f[R]. .SS Named Expressions .PP The following are named expressions in bc(1): .IP "1." 3 Variables: \f[B]I\f[R] .IP "2." 3 Array Elements: \f[B]I[E]\f[R] .IP "3." 3 \f[B]ibase\f[R] .IP "4." 3 \f[B]obase\f[R] .IP "5." 3 \f[B]scale\f[R] .IP "6." 3 \f[B]last\f[R] or a single dot (\f[B].\f[R]) .PP Number 6 is a \f[B]non-portable extension\f[R]. .PP Variables and arrays do not interfere; users can have arrays named the same as variables. This also applies to functions (see the \f[B]FUNCTIONS\f[R] section), so a user can have a variable, array, and function that all have the same name, and they will not shadow each other, whether inside of functions or not. .PP Named expressions are required as the operand of \f[B]increment\f[R]/\f[B]decrement\f[R] operators and as the left side of \f[B]assignment\f[R] operators (see the \f[I]Operators\f[R] subsection). .SS Operands .PP The following are valid operands in bc(1): .IP " 1." 4 Numbers (see the \f[I]Numbers\f[R] subsection below). .IP " 2." 4 Array indices (\f[B]I[E]\f[R]). .IP " 3." 4 \f[B](E)\f[R]: The value of \f[B]E\f[R] (used to change precedence). .IP " 4." 4 \f[B]sqrt(E)\f[R]: The square root of \f[B]E\f[R]. \f[B]E\f[R] must be non-negative. .IP " 5." 4 \f[B]length(E)\f[R]: The number of significant decimal digits in \f[B]E\f[R]. Returns \f[B]1\f[R] for \f[B]0\f[R] with no decimal places. If given a string, the length of the string is returned. Passing a string to \f[B]length(E)\f[R] is a \f[B]non-portable extension\f[R]. .IP " 6." 4 \f[B]length(I[])\f[R]: The number of elements in the array \f[B]I\f[R]. This is a \f[B]non-portable extension\f[R]. .IP " 7." 4 \f[B]scale(E)\f[R]: The \f[I]scale\f[R] of \f[B]E\f[R]. .IP " 8." 4 \f[B]abs(E)\f[R]: The absolute value of \f[B]E\f[R]. This is a \f[B]non-portable extension\f[R]. .IP " 9." 4 \f[B]modexp(E, E, E)\f[R]: Modular exponentiation, where the first expression is the base, the second is the exponent, and the third is the modulus. All three values must be integers. The second argument must be non-negative. The third argument must be non-zero. This is a \f[B]non-portable extension\f[R]. .IP "10." 4 \f[B]divmod(E, E, I[])\f[R]: Division and modulus in one operation. This is for optimization. The first expression is the dividend, and the second is the divisor, which must be non-zero. The return value is the quotient, and the modulus is stored in index \f[B]0\f[R] of the provided array (the last argument). This is a \f[B]non-portable extension\f[R]. .IP "11." 4 \f[B]asciify(E)\f[R]: If \f[B]E\f[R] is a string, returns a string that is the first letter of its argument. If it is a number, calculates the number mod \f[B]256\f[R] and returns that number as a one-character string. This is a \f[B]non-portable extension\f[R]. .IP "12." 4 \f[B]I()\f[R], \f[B]I(E)\f[R], \f[B]I(E, E)\f[R], and so on, where \f[B]I\f[R] is an identifier for a non-\f[B]void\f[R] function (see the \f[I]Void Functions\f[R] subsection of the \f[B]FUNCTIONS\f[R] section). The \f[B]E\f[R] argument(s) may also be arrays of the form \f[B]I[]\f[R], which will automatically be turned into array references (see the \f[I]Array References\f[R] subsection of the \f[B]FUNCTIONS\f[R] section) if the corresponding parameter in the function definition is an array reference. .IP "13." 4 \f[B]read()\f[R]: Reads a line from \f[B]stdin\f[R] and uses that as an expression. The result of that expression is the result of the \f[B]read()\f[R] operand. This is a \f[B]non-portable extension\f[R]. .IP "14." 4 \f[B]maxibase()\f[R]: The max allowable \f[B]ibase\f[R]. This is a \f[B]non-portable extension\f[R]. .IP "15." 4 \f[B]maxobase()\f[R]: The max allowable \f[B]obase\f[R]. This is a \f[B]non-portable extension\f[R]. .IP "16." 4 \f[B]maxscale()\f[R]: The max allowable \f[B]scale\f[R]. This is a \f[B]non-portable extension\f[R]. .IP "17." 4 \f[B]line_length()\f[R]: The line length set with \f[B]BC_LINE_LENGTH\f[R] (see the \f[B]ENVIRONMENT VARIABLES\f[R] section). This is a \f[B]non-portable extension\f[R]. .IP "18." 4 \f[B]global_stacks()\f[R]: \f[B]0\f[R] if global stacks are not enabled with the \f[B]-g\f[R] or \f[B]--global-stacks\f[R] options, non-zero otherwise. See the \f[B]OPTIONS\f[R] section. This is a \f[B]non-portable extension\f[R]. .IP "19." 4 \f[B]leading_zero()\f[R]: \f[B]0\f[R] if leading zeroes are not enabled with the \f[B]-z\f[R] or \f[B]\[en]leading-zeroes\f[R] options, non-zero otherwise. See the \f[B]OPTIONS\f[R] section. This is a \f[B]non-portable extension\f[R]. .SS Numbers .PP Numbers are strings made up of digits, uppercase letters, and at most \f[B]1\f[R] period for a radix. Numbers can have up to \f[B]BC_NUM_MAX\f[R] digits. Uppercase letters are equal to \f[B]9\f[R] + their position in the alphabet (i.e., \f[B]A\f[R] equals \f[B]10\f[R], or \f[B]9+1\f[R]). If a digit or letter makes no sense with the current value of \f[B]ibase\f[R], they are set to the value of the highest valid digit in \f[B]ibase\f[R]. .PP Single-character numbers (i.e., \f[B]A\f[R] alone) take the value that they would have if they were valid digits, regardless of the value of \f[B]ibase\f[R]. This means that \f[B]A\f[R] alone always equals decimal \f[B]10\f[R] and \f[B]Z\f[R] alone always equals decimal \f[B]35\f[R]. .SS Operators .PP The following arithmetic and logical operators can be used. They are listed in order of decreasing precedence. Operators in the same group have the same precedence. .TP \f[B]++\f[R] \f[B]--\f[R] Type: Prefix and Postfix .RS .PP Associativity: None .PP Description: \f[B]increment\f[R], \f[B]decrement\f[R] .RE .TP \f[B]-\f[R] \f[B]!\f[R] Type: Prefix .RS .PP Associativity: None .PP Description: \f[B]negation\f[R], \f[B]boolean not\f[R] .RE .TP \f[B]\[ha]\f[R] Type: Binary .RS .PP Associativity: Right .PP Description: \f[B]power\f[R] .RE .TP \f[B]*\f[R] \f[B]/\f[R] \f[B]%\f[R] Type: Binary .RS .PP Associativity: Left .PP Description: \f[B]multiply\f[R], \f[B]divide\f[R], \f[B]modulus\f[R] .RE .TP \f[B]+\f[R] \f[B]-\f[R] Type: Binary .RS .PP Associativity: Left .PP Description: \f[B]add\f[R], \f[B]subtract\f[R] .RE .TP \f[B]=\f[R] \f[B]+=\f[R] \f[B]-=\f[R] \f[B]*=\f[R] \f[B]/=\f[R] \f[B]%=\f[R] \f[B]\[ha]=\f[R] Type: Binary .RS .PP Associativity: Right .PP Description: \f[B]assignment\f[R] .RE .TP \f[B]==\f[R] \f[B]<=\f[R] \f[B]>=\f[R] \f[B]!=\f[R] \f[B]<\f[R] \f[B]>\f[R] Type: Binary .RS .PP Associativity: Left .PP Description: \f[B]relational\f[R] .RE .TP \f[B]&&\f[R] Type: Binary .RS .PP Associativity: Left .PP Description: \f[B]boolean and\f[R] .RE .TP \f[B]||\f[R] Type: Binary .RS .PP Associativity: Left .PP Description: \f[B]boolean or\f[R] .RE .PP The operators will be described in more detail below. .TP \f[B]++\f[R] \f[B]--\f[R] The prefix and postfix \f[B]increment\f[R] and \f[B]decrement\f[R] operators behave exactly like they would in C. They require a named expression (see the \f[I]Named Expressions\f[R] subsection) as an operand. .RS .PP The prefix versions of these operators are more efficient; use them where possible. .RE .TP \f[B]-\f[R] The \f[B]negation\f[R] operator returns \f[B]0\f[R] if a user attempts to negate any expression with the value \f[B]0\f[R]. Otherwise, a copy of the expression with its sign flipped is returned. .TP \f[B]!\f[R] The \f[B]boolean not\f[R] operator returns \f[B]1\f[R] if the expression is \f[B]0\f[R], or \f[B]0\f[R] otherwise. .RS .PP This is a \f[B]non-portable extension\f[R]. .RE .TP \f[B]\[ha]\f[R] The \f[B]power\f[R] operator (not the \f[B]exclusive or\f[R] operator, as it would be in C) takes two expressions and raises the first to the power of the value of the second. The \f[I]scale\f[R] of the result is equal to \f[B]scale\f[R]. .RS .PP The second expression must be an integer (no \f[I]scale\f[R]), and if it is negative, the first value must be non-zero. .RE .TP \f[B]*\f[R] The \f[B]multiply\f[R] operator takes two expressions, multiplies them, and returns the product. If \f[B]a\f[R] is the \f[I]scale\f[R] of the first expression and \f[B]b\f[R] is the \f[I]scale\f[R] of the second expression, the \f[I]scale\f[R] of the result is equal to \f[B]min(a+b,max(scale,a,b))\f[R] where \f[B]min()\f[R] and \f[B]max()\f[R] return the obvious values. .TP \f[B]/\f[R] The \f[B]divide\f[R] operator takes two expressions, divides them, and returns the quotient. The \f[I]scale\f[R] of the result shall be the value of \f[B]scale\f[R]. .RS .PP The second expression must be non-zero. .RE .TP \f[B]%\f[R] The \f[B]modulus\f[R] operator takes two expressions, \f[B]a\f[R] and \f[B]b\f[R], and evaluates them by 1) Computing \f[B]a/b\f[R] to current \f[B]scale\f[R] and 2) Using the result of step 1 to calculate \f[B]a-(a/b)*b\f[R] to \f[I]scale\f[R] \f[B]max(scale+scale(b),scale(a))\f[R]. .RS .PP The second expression must be non-zero. .RE .TP \f[B]+\f[R] The \f[B]add\f[R] operator takes two expressions, \f[B]a\f[R] and \f[B]b\f[R], and returns the sum, with a \f[I]scale\f[R] equal to the max of the \f[I]scale\f[R]s of \f[B]a\f[R] and \f[B]b\f[R]. .TP \f[B]-\f[R] The \f[B]subtract\f[R] operator takes two expressions, \f[B]a\f[R] and \f[B]b\f[R], and returns the difference, with a \f[I]scale\f[R] equal to the max of the \f[I]scale\f[R]s of \f[B]a\f[R] and \f[B]b\f[R]. .TP \f[B]=\f[R] \f[B]+=\f[R] \f[B]-=\f[R] \f[B]*=\f[R] \f[B]/=\f[R] \f[B]%=\f[R] \f[B]\[ha]=\f[R] The \f[B]assignment\f[R] operators take two expressions, \f[B]a\f[R] and \f[B]b\f[R] where \f[B]a\f[R] is a named expression (see the \f[I]Named Expressions\f[R] subsection). .RS .PP For \f[B]=\f[R], \f[B]b\f[R] is copied and the result is assigned to \f[B]a\f[R]. For all others, \f[B]a\f[R] and \f[B]b\f[R] are applied as operands to the corresponding arithmetic operator and the result is assigned to \f[B]a\f[R]. .RE .TP \f[B]==\f[R] \f[B]<=\f[R] \f[B]>=\f[R] \f[B]!=\f[R] \f[B]<\f[R] \f[B]>\f[R] The \f[B]relational\f[R] operators compare two expressions, \f[B]a\f[R] and \f[B]b\f[R], and if the relation holds, according to C language semantics, the result is \f[B]1\f[R]. Otherwise, it is \f[B]0\f[R]. .RS .PP Note that unlike in C, these operators have a lower precedence than the \f[B]assignment\f[R] operators, which means that \f[B]a=b>c\f[R] is interpreted as \f[B](a=b)>c\f[R]. .PP Also, unlike the standard (https://pubs.opengroup.org/onlinepubs/9699919799/utilities/bc.html) requires, these operators can appear anywhere any other expressions can be used. This allowance is a \f[B]non-portable extension\f[R]. .RE .TP \f[B]&&\f[R] The \f[B]boolean and\f[R] operator takes two expressions and returns \f[B]1\f[R] if both expressions are non-zero, \f[B]0\f[R] otherwise. .RS .PP This is \f[I]not\f[R] a short-circuit operator. .PP This is a \f[B]non-portable extension\f[R]. .RE .TP \f[B]||\f[R] The \f[B]boolean or\f[R] operator takes two expressions and returns \f[B]1\f[R] if one of the expressions is non-zero, \f[B]0\f[R] otherwise. .RS .PP This is \f[I]not\f[R] a short-circuit operator. .PP This is a \f[B]non-portable extension\f[R]. .RE .SS Statements .PP The following items are statements: .IP " 1." 4 \f[B]E\f[R] .IP " 2." 4 \f[B]{\f[R] \f[B]S\f[R] \f[B];\f[R] \&... \f[B];\f[R] \f[B]S\f[R] \f[B]}\f[R] .IP " 3." 4 \f[B]if\f[R] \f[B](\f[R] \f[B]E\f[R] \f[B])\f[R] \f[B]S\f[R] .IP " 4." 4 \f[B]if\f[R] \f[B](\f[R] \f[B]E\f[R] \f[B])\f[R] \f[B]S\f[R] \f[B]else\f[R] \f[B]S\f[R] .IP " 5." 4 \f[B]while\f[R] \f[B](\f[R] \f[B]E\f[R] \f[B])\f[R] \f[B]S\f[R] .IP " 6." 4 \f[B]for\f[R] \f[B](\f[R] \f[B]E\f[R] \f[B];\f[R] \f[B]E\f[R] \f[B];\f[R] \f[B]E\f[R] \f[B])\f[R] \f[B]S\f[R] .IP " 7." 4 An empty statement .IP " 8." 4 \f[B]break\f[R] .IP " 9." 4 \f[B]continue\f[R] .IP "10." 4 \f[B]quit\f[R] .IP "11." 4 \f[B]halt\f[R] .IP "12." 4 \f[B]limits\f[R] .IP "13." 4 A string of characters, enclosed in double quotes .IP "14." 4 \f[B]print\f[R] \f[B]E\f[R] \f[B],\f[R] \&... \f[B],\f[R] \f[B]E\f[R] .IP "15." 4 \f[B]stream\f[R] \f[B]E\f[R] \f[B],\f[R] \&... \f[B],\f[R] \f[B]E\f[R] .IP "16." 4 \f[B]I()\f[R], \f[B]I(E)\f[R], \f[B]I(E, E)\f[R], and so on, where \f[B]I\f[R] is an identifier for a \f[B]void\f[R] function (see the \f[I]Void Functions\f[R] subsection of the \f[B]FUNCTIONS\f[R] section). The \f[B]E\f[R] argument(s) may also be arrays of the form \f[B]I[]\f[R], which will automatically be turned into array references (see the \f[I]Array References\f[R] subsection of the \f[B]FUNCTIONS\f[R] section) if the corresponding parameter in the function definition is an array reference. .PP Numbers 4, 9, 11, 12, 14, 15, and 16 are \f[B]non-portable extensions\f[R]. .PP Also, as a \f[B]non-portable extension\f[R], any or all of the expressions in the header of a for loop may be omitted. If the condition (second expression) is omitted, it is assumed to be a constant \f[B]1\f[R]. .PP The \f[B]break\f[R] statement causes a loop to stop iterating and resume execution immediately following a loop. This is only allowed in loops. .PP The \f[B]continue\f[R] statement causes a loop iteration to stop early and returns to the start of the loop, including testing the loop condition. This is only allowed in loops. .PP The \f[B]if\f[R] \f[B]else\f[R] statement does the same thing as in C. .PP The \f[B]quit\f[R] statement causes bc(1) to quit, even if it is on a branch that will not be executed (it is a compile-time command). .PP The \f[B]halt\f[R] statement causes bc(1) to quit, if it is executed. (Unlike \f[B]quit\f[R] if it is on a branch of an \f[B]if\f[R] statement that is not executed, bc(1) does not quit.) .PP The \f[B]limits\f[R] statement prints the limits that this bc(1) is subject to. This is like the \f[B]quit\f[R] statement in that it is a compile-time command. .PP An expression by itself is evaluated and printed, followed by a newline. .SS Strings .PP If strings appear as a statement by themselves, they are printed without a trailing newline. .PP In addition to appearing as a lone statement by themselves, strings can be assigned to variables and array elements. They can also be passed to functions in variable parameters. .PP If any statement that expects a string is given a variable that had a string assigned to it, the statement acts as though it had received a string. .PP If any math operation is attempted on a string or a variable or array element that has been assigned a string, an error is raised, and bc(1) resets (see the \f[B]RESET\f[R] section). .PP Assigning strings to variables and array elements and passing them to functions are \f[B]non-portable extensions\f[R]. .SS Print Statement .PP The \[lq]expressions\[rq] in a \f[B]print\f[R] statement may also be strings. If they are, there are backslash escape sequences that are interpreted specially. What those sequences are, and what they cause to be printed, are shown below: .PP \f[B]\[rs]a\f[R]: \f[B]\[rs]a\f[R] .PP \f[B]\[rs]b\f[R]: \f[B]\[rs]b\f[R] .PP \f[B]\[rs]\[rs]\f[R]: \f[B]\[rs]\f[R] .PP \f[B]\[rs]e\f[R]: \f[B]\[rs]\f[R] .PP \f[B]\[rs]f\f[R]: \f[B]\[rs]f\f[R] .PP \f[B]\[rs]n\f[R]: \f[B]\[rs]n\f[R] .PP \f[B]\[rs]q\f[R]: \f[B]\[lq]\f[R] .PP \f[B]\[rs]r\f[R]: \f[B]\[rs]r\f[R] .PP \f[B]\[rs]t\f[R]: \f[B]\[rs]t\f[R] .PP Any other character following a backslash causes the backslash and character to be printed as-is. .PP Any non-string expression in a print statement shall be assigned to \f[B]last\f[R], like any other expression that is printed. .SS Stream Statement .PP The \[lq]expressions in a \f[B]stream\f[R] statement may also be strings. .PP If a \f[B]stream\f[R] statement is given a string, it prints the string as though the string had appeared as its own statement. In other words, the \f[B]stream\f[R] statement prints strings normally, without a newline. .PP If a \f[B]stream\f[R] statement is given a number, a copy of it is truncated and its absolute value is calculated. The result is then printed as though \f[B]obase\f[R] is \f[B]256\f[R] and each digit is interpreted as an 8-bit ASCII character, making it a byte stream. .SS Order of Evaluation .PP All expressions in a statment are evaluated left to right, except as necessary to maintain order of operations. This means, for example, assuming that \f[B]i\f[R] is equal to \f[B]0\f[R], in the expression .IP .nf \f[C] a[i++] = i++ \f[R] .fi .PP the first (or 0th) element of \f[B]a\f[R] is set to \f[B]1\f[R], and \f[B]i\f[R] is equal to \f[B]2\f[R] at the end of the expression. .PP This includes function arguments. Thus, assuming \f[B]i\f[R] is equal to \f[B]0\f[R], this means that in the expression .IP .nf \f[C] x(i++, i++) \f[R] .fi .PP the first argument passed to \f[B]x()\f[R] is \f[B]0\f[R], and the second argument is \f[B]1\f[R], while \f[B]i\f[R] is equal to \f[B]2\f[R] before the function starts executing. .SH FUNCTIONS .PP Function definitions are as follows: .IP .nf \f[C] define I(I,...,I){ auto I,...,I S;...;S return(E) } \f[R] .fi .PP Any \f[B]I\f[R] in the parameter list or \f[B]auto\f[R] list may be replaced with \f[B]I[]\f[R] to make a parameter or \f[B]auto\f[R] var an array, and any \f[B]I\f[R] in the parameter list may be replaced with \f[B]*I[]\f[R] to make a parameter an array reference. Callers of functions that take array references should not put an asterisk in the call; they must be called with just \f[B]I[]\f[R] like normal array parameters and will be automatically converted into references. .PP As a \f[B]non-portable extension\f[R], the opening brace of a \f[B]define\f[R] statement may appear on the next line. .PP As a \f[B]non-portable extension\f[R], the return statement may also be in one of the following forms: .IP "1." 3 \f[B]return\f[R] .IP "2." 3 \f[B]return\f[R] \f[B](\f[R] \f[B])\f[R] .IP "3." 3 \f[B]return\f[R] \f[B]E\f[R] .PP The first two, or not specifying a \f[B]return\f[R] statement, is equivalent to \f[B]return (0)\f[R], unless the function is a \f[B]void\f[R] function (see the \f[I]Void Functions\f[R] subsection below). .SS Void Functions .PP Functions can also be \f[B]void\f[R] functions, defined as follows: .IP .nf \f[C] define void I(I,...,I){ auto I,...,I S;...;S return } \f[R] .fi .PP They can only be used as standalone expressions, where such an expression would be printed alone, except in a print statement. .PP Void functions can only use the first two \f[B]return\f[R] statements listed above. They can also omit the return statement entirely. .PP The word \[lq]void\[rq] is not treated as a keyword; it is still possible to have variables, arrays, and functions named \f[B]void\f[R]. The word \[lq]void\[rq] is only treated specially right after the \f[B]define\f[R] keyword. .PP This is a \f[B]non-portable extension\f[R]. .SS Array References .PP For any array in the parameter list, if the array is declared in the form .IP .nf \f[C] *I[] \f[R] .fi .PP it is a \f[B]reference\f[R]. Any changes to the array in the function are reflected, when the function returns, to the array that was passed in. .PP Other than this, all function arguments are passed by value. .PP This is a \f[B]non-portable extension\f[R]. .SH LIBRARY .PP All of the functions below are available when the \f[B]-l\f[R] or \f[B]--mathlib\f[R] command-line flags are given. .SS Standard Library .PP The standard (https://pubs.opengroup.org/onlinepubs/9699919799/utilities/bc.html) defines the following functions for the math library: .TP \f[B]s(x)\f[R] Returns the sine of \f[B]x\f[R], which is assumed to be in radians. .RS .PP This is a transcendental function (see the \f[I]Transcendental Functions\f[R] subsection below). .RE .TP \f[B]c(x)\f[R] Returns the cosine of \f[B]x\f[R], which is assumed to be in radians. .RS .PP This is a transcendental function (see the \f[I]Transcendental Functions\f[R] subsection below). .RE .TP \f[B]a(x)\f[R] Returns the arctangent of \f[B]x\f[R], in radians. .RS .PP This is a transcendental function (see the \f[I]Transcendental Functions\f[R] subsection below). .RE .TP \f[B]l(x)\f[R] Returns the natural logarithm of \f[B]x\f[R]. .RS .PP This is a transcendental function (see the \f[I]Transcendental Functions\f[R] subsection below). .RE .TP \f[B]e(x)\f[R] Returns the mathematical constant \f[B]e\f[R] raised to the power of \f[B]x\f[R]. .RS .PP This is a transcendental function (see the \f[I]Transcendental Functions\f[R] subsection below). .RE .TP \f[B]j(x, n)\f[R] Returns the bessel integer order \f[B]n\f[R] (truncated) of \f[B]x\f[R]. .RS .PP This is a transcendental function (see the \f[I]Transcendental Functions\f[R] subsection below). .RE .SS Transcendental Functions .PP All transcendental functions can return slightly inaccurate results (up to 1 ULP (https://en.wikipedia.org/wiki/Unit_in_the_last_place)). This is unavoidable, and this article (https://people.eecs.berkeley.edu/~wkahan/LOG10HAF.TXT) explains why it is impossible and unnecessary to calculate exact results for the transcendental functions. .PP Because of the possible inaccuracy, I recommend that users call those functions with the precision (\f[B]scale\f[R]) set to at least 1 higher than is necessary. If exact results are \f[I]absolutely\f[R] required, users can double the precision (\f[B]scale\f[R]) and then truncate. .PP The transcendental functions in the standard math library are: .IP \[bu] 2 \f[B]s(x)\f[R] .IP \[bu] 2 \f[B]c(x)\f[R] .IP \[bu] 2 \f[B]a(x)\f[R] .IP \[bu] 2 \f[B]l(x)\f[R] .IP \[bu] 2 \f[B]e(x)\f[R] .IP \[bu] 2 \f[B]j(x, n)\f[R] .SH RESET .PP When bc(1) encounters an error or a signal that it has a non-default handler for, it resets. This means that several things happen. .PP First, any functions that are executing are stopped and popped off the stack. The behavior is not unlike that of exceptions in programming languages. Then the execution point is set so that any code waiting to execute (after all functions returned) is skipped. .PP Thus, when bc(1) resets, it skips any remaining code waiting to be executed. Then, if it is interactive mode, and the error was not a fatal error (see the \f[B]EXIT STATUS\f[R] section), it asks for more input; otherwise, it exits with the appropriate return code. .PP Note that this reset behavior is different from the GNU bc(1), which attempts to start executing the statement right after the one that caused an error. .SH PERFORMANCE .PP Most bc(1) implementations use \f[B]char\f[R] types to calculate the value of \f[B]1\f[R] decimal digit at a time, but that can be slow. This bc(1) does something different. .PP It uses large integers to calculate more than \f[B]1\f[R] decimal digit at a time. If built in a environment where \f[B]BC_LONG_BIT\f[R] (see the \f[B]LIMITS\f[R] section) is \f[B]64\f[R], then each integer has \f[B]9\f[R] decimal digits. If built in an environment where \f[B]BC_LONG_BIT\f[R] is \f[B]32\f[R] then each integer has \f[B]4\f[R] decimal digits. This value (the number of decimal digits per large integer) is called \f[B]BC_BASE_DIGS\f[R]. .PP The actual values of \f[B]BC_LONG_BIT\f[R] and \f[B]BC_BASE_DIGS\f[R] can be queried with the \f[B]limits\f[R] statement. .PP In addition, this bc(1) uses an even larger integer for overflow checking. This integer type depends on the value of \f[B]BC_LONG_BIT\f[R], but is always at least twice as large as the integer type used to store digits. .SH LIMITS .PP The following are the limits on bc(1): .TP \f[B]BC_LONG_BIT\f[R] The number of bits in the \f[B]long\f[R] type in the environment where bc(1) was built. This determines how many decimal digits can be stored in a single large integer (see the \f[B]PERFORMANCE\f[R] section). .TP \f[B]BC_BASE_DIGS\f[R] The number of decimal digits per large integer (see the \f[B]PERFORMANCE\f[R] section). Depends on \f[B]BC_LONG_BIT\f[R]. .TP \f[B]BC_BASE_POW\f[R] The max decimal number that each large integer can store (see \f[B]BC_BASE_DIGS\f[R]) plus \f[B]1\f[R]. Depends on \f[B]BC_BASE_DIGS\f[R]. .TP \f[B]BC_OVERFLOW_MAX\f[R] The max number that the overflow type (see the \f[B]PERFORMANCE\f[R] section) can hold. Depends on \f[B]BC_LONG_BIT\f[R]. .TP \f[B]BC_BASE_MAX\f[R] The maximum output base. Set at \f[B]BC_BASE_POW\f[R]. .TP \f[B]BC_DIM_MAX\f[R] The maximum size of arrays. Set at \f[B]SIZE_MAX-1\f[R]. .TP \f[B]BC_SCALE_MAX\f[R] The maximum \f[B]scale\f[R]. Set at \f[B]BC_OVERFLOW_MAX-1\f[R]. .TP \f[B]BC_STRING_MAX\f[R] The maximum length of strings. Set at \f[B]BC_OVERFLOW_MAX-1\f[R]. .TP \f[B]BC_NAME_MAX\f[R] The maximum length of identifiers. Set at \f[B]BC_OVERFLOW_MAX-1\f[R]. .TP \f[B]BC_NUM_MAX\f[R] The maximum length of a number (in decimal digits), which includes digits after the decimal point. Set at \f[B]BC_OVERFLOW_MAX-1\f[R]. .TP Exponent The maximum allowable exponent (positive or negative). Set at \f[B]BC_OVERFLOW_MAX\f[R]. .TP Number of vars The maximum number of vars/arrays. Set at \f[B]SIZE_MAX-1\f[R]. .PP The actual values can be queried with the \f[B]limits\f[R] statement. .PP These limits are meant to be effectively non-existent; the limits are so large (at least on 64-bit machines) that there should not be any point at which they become a problem. In fact, memory should be exhausted before these limits should be hit. .SH ENVIRONMENT VARIABLES .PP bc(1) recognizes the following environment variables: .TP \f[B]POSIXLY_CORRECT\f[R] If this variable exists (no matter the contents), bc(1) behaves as if the \f[B]-s\f[R] option was given. .TP \f[B]BC_ENV_ARGS\f[R] This is another way to give command-line arguments to bc(1). They should be in the same format as all other command-line arguments. These are always processed first, so any files given in \f[B]BC_ENV_ARGS\f[R] will be processed before arguments and files given on the command-line. This gives the user the ability to set up \[lq]standard\[rq] options and files to be used at every invocation. The most useful thing for such files to contain would be useful functions that the user might want every time bc(1) runs. .RS .PP The code that parses \f[B]BC_ENV_ARGS\f[R] will correctly handle quoted arguments, but it does not understand escape sequences. For example, the string \f[B]\[lq]/home/gavin/some bc file.bc\[rq]\f[R] will be correctly parsed, but the string \f[B]\[lq]/home/gavin/some \[dq]bc\[dq] file.bc\[rq]\f[R] will include the backslashes. .PP The quote parsing will handle either kind of quotes, \f[B]\[cq]\f[R] or \f[B]\[lq]\f[R]. Thus, if you have a file with any number of single quotes in the name, you can use double quotes as the outside quotes, as in \f[B]\[lq]some `bc' file.bc\[rq]\f[R], and vice versa if you have a file with double quotes. However, handling a file with both kinds of quotes in \f[B]BC_ENV_ARGS\f[R] is not supported due to the complexity of the parsing, though such files are still supported on the command-line where the parsing is done by the shell. .RE .TP \f[B]BC_LINE_LENGTH\f[R] If this environment variable exists and contains an integer that is greater than \f[B]1\f[R] and is less than \f[B]UINT16_MAX\f[R] (\f[B]2\[ha]16-1\f[R]), bc(1) will output lines to that length, including the backslash (\f[B]\[rs]\f[R]). The default line length is \f[B]70\f[R]. .RS .PP The special value of \f[B]0\f[R] will disable line length checking and print numbers without regard to line length and without backslashes and newlines. .RE .TP \f[B]BC_BANNER\f[R] If this environment variable exists and contains an integer, then a non-zero value activates the copyright banner when bc(1) is in interactive mode, while zero deactivates it. .RS .PP If bc(1) is not in interactive mode (see the \f[B]INTERACTIVE MODE\f[R] section), then this environment variable has no effect because bc(1) does not print the banner when not in interactive mode. .PP This environment variable overrides the default, which can be queried with the \f[B]-h\f[R] or \f[B]--help\f[R] options. .RE .TP \f[B]BC_SIGINT_RESET\f[R] If bc(1) is not in interactive mode (see the \f[B]INTERACTIVE MODE\f[R] section), then this environment variable has no effect because bc(1) exits on \f[B]SIGINT\f[R] when not in interactive mode. .RS .PP However, when bc(1) is in interactive mode, then if this environment variable exists and contains an integer, a non-zero value makes bc(1) reset on \f[B]SIGINT\f[R], rather than exit, and zero makes bc(1) exit. If this environment variable exists and is \f[I]not\f[R] an integer, then bc(1) will exit on \f[B]SIGINT\f[R]. .PP This environment variable overrides the default, which can be queried with the \f[B]-h\f[R] or \f[B]--help\f[R] options. .RE .TP \f[B]BC_TTY_MODE\f[R] If TTY mode is \f[I]not\f[R] available (see the \f[B]TTY MODE\f[R] section), then this environment variable has no effect. .RS .PP However, when TTY mode is available, then if this environment variable exists and contains an integer, then a non-zero value makes bc(1) use TTY mode, and zero makes bc(1) not use TTY mode. .PP This environment variable overrides the default, which can be queried with the \f[B]-h\f[R] or \f[B]--help\f[R] options. .RE .TP \f[B]BC_PROMPT\f[R] If TTY mode is \f[I]not\f[R] available (see the \f[B]TTY MODE\f[R] section), then this environment variable has no effect. .RS .PP However, when TTY mode is available, then if this environment variable exists and contains an integer, a non-zero value makes bc(1) use a prompt, and zero or a non-integer makes bc(1) not use a prompt. If this environment variable does not exist and \f[B]BC_TTY_MODE\f[R] does, then the value of the \f[B]BC_TTY_MODE\f[R] environment variable is used. .PP This environment variable and the \f[B]BC_TTY_MODE\f[R] environment variable override the default, which can be queried with the \f[B]-h\f[R] or \f[B]--help\f[R] options. .RE +.TP +\f[B]BC_EXPR_EXIT\f[R] +If any expressions or expression files are given on the command-line +with \f[B]-e\f[R], \f[B]--expression\f[R], \f[B]-f\f[R], or +\f[B]--file\f[R], then if this environment variable exists and contains +an integer, a non-zero value makes bc(1) exit after executing the +expressions and expression files, and a non-zero value makes bc(1) not +exit. +.RS +.PP +This environment variable overrides the default, which can be queried +with the \f[B]-h\f[R] or \f[B]--help\f[R] options. +.RE .SH EXIT STATUS .PP bc(1) returns the following exit statuses: .TP \f[B]0\f[R] No error. .TP \f[B]1\f[R] A math error occurred. This follows standard practice of using \f[B]1\f[R] for expected errors, since math errors will happen in the process of normal execution. .RS .PP Math errors include divide by \f[B]0\f[R], taking the square root of a negative number, attempting to convert a negative number to a hardware integer, overflow when converting a number to a hardware integer, overflow when calculating the size of a number, and attempting to use a non-integer where an integer is required. .PP Converting to a hardware integer happens for the second operand of the power (\f[B]\[ha]\f[R]) operator and the corresponding assignment operator. .RE .TP \f[B]2\f[R] A parse error occurred. .RS .PP Parse errors include unexpected \f[B]EOF\f[R], using an invalid character, failing to find the end of a string or comment, using a token where it is invalid, giving an invalid expression, giving an invalid print statement, giving an invalid function definition, attempting to assign to an expression that is not a named expression (see the \f[I]Named Expressions\f[R] subsection of the \f[B]SYNTAX\f[R] section), giving an invalid \f[B]auto\f[R] list, having a duplicate \f[B]auto\f[R]/function parameter, failing to find the end of a code block, attempting to return a value from a \f[B]void\f[R] function, attempting to use a variable as a reference, and using any extensions when the option \f[B]-s\f[R] or any equivalents were given. .RE .TP \f[B]3\f[R] A runtime error occurred. .RS .PP Runtime errors include assigning an invalid number to any global (\f[B]ibase\f[R], \f[B]obase\f[R], or \f[B]scale\f[R]), giving a bad expression to a \f[B]read()\f[R] call, calling \f[B]read()\f[R] inside of a \f[B]read()\f[R] call, type errors, passing the wrong number of arguments to functions, attempting to call an undefined function, and attempting to use a \f[B]void\f[R] function call as a value in an expression. .RE .TP \f[B]4\f[R] A fatal error occurred. .RS .PP Fatal errors include memory allocation errors, I/O errors, failing to open files, attempting to use files that do not have only ASCII characters (bc(1) only accepts ASCII characters), attempting to open a directory as a file, and giving invalid command-line options. .RE .PP The exit status \f[B]4\f[R] is special; when a fatal error occurs, bc(1) always exits and returns \f[B]4\f[R], no matter what mode bc(1) is in. .PP The other statuses will only be returned when bc(1) is not in interactive mode (see the \f[B]INTERACTIVE MODE\f[R] section), since bc(1) resets its state (see the \f[B]RESET\f[R] section) and accepts more input when one of those errors occurs in interactive mode. This is also the case when interactive mode is forced by the \f[B]-i\f[R] flag or \f[B]--interactive\f[R] option. .PP These exit statuses allow bc(1) to be used in shell scripting with error checking, and its normal behavior can be forced by using the \f[B]-i\f[R] flag or \f[B]--interactive\f[R] option. .SH INTERACTIVE MODE .PP Per the standard (https://pubs.opengroup.org/onlinepubs/9699919799/utilities/bc.html), bc(1) has an interactive mode and a non-interactive mode. Interactive mode is turned on automatically when both \f[B]stdin\f[R] and \f[B]stdout\f[R] are hooked to a terminal, but the \f[B]-i\f[R] flag and \f[B]--interactive\f[R] option can turn it on in other situations. .PP In interactive mode, bc(1) attempts to recover from errors (see the \f[B]RESET\f[R] section), and in normal execution, flushes \f[B]stdout\f[R] as soon as execution is done for the current input. bc(1) may also reset on \f[B]SIGINT\f[R] instead of exit, depending on the contents of, or default for, the \f[B]BC_SIGINT_RESET\f[R] environment variable (see the \f[B]ENVIRONMENT VARIABLES\f[R] section). .SH TTY MODE .PP If \f[B]stdin\f[R], \f[B]stdout\f[R], and \f[B]stderr\f[R] are all connected to a TTY, then \[lq]TTY mode\[rq] is considered to be available, and thus, bc(1) can turn on TTY mode, subject to some settings. .PP If there is the environment variable \f[B]BC_TTY_MODE\f[R] in the environment (see the \f[B]ENVIRONMENT VARIABLES\f[R] section), then if that environment variable contains a non-zero integer, bc(1) will turn on TTY mode when \f[B]stdin\f[R], \f[B]stdout\f[R], and \f[B]stderr\f[R] are all connected to a TTY. If the \f[B]BC_TTY_MODE\f[R] environment variable exists but is \f[I]not\f[R] a non-zero integer, then bc(1) will not turn TTY mode on. .PP If the environment variable \f[B]BC_TTY_MODE\f[R] does \f[I]not\f[R] exist, the default setting is used. The default setting can be queried with the \f[B]-h\f[R] or \f[B]--help\f[R] options. .PP TTY mode is different from interactive mode because interactive mode is required in the bc(1) specification (https://pubs.opengroup.org/onlinepubs/9699919799/utilities/bc.html), and interactive mode requires only \f[B]stdin\f[R] and \f[B]stdout\f[R] to be connected to a terminal. .SS Prompt .PP If TTY mode is available, then a prompt can be enabled. Like TTY mode itself, it can be turned on or off with an environment variable: \f[B]BC_PROMPT\f[R] (see the \f[B]ENVIRONMENT VARIABLES\f[R] section). .PP If the environment variable \f[B]BC_PROMPT\f[R] exists and is a non-zero integer, then the prompt is turned on when \f[B]stdin\f[R], \f[B]stdout\f[R], and \f[B]stderr\f[R] are connected to a TTY and the \f[B]-P\f[R] and \f[B]--no-prompt\f[R] options were not used. The read prompt will be turned on under the same conditions, except that the \f[B]-R\f[R] and \f[B]--no-read-prompt\f[R] options must also not be used. .PP However, if \f[B]BC_PROMPT\f[R] does not exist, the prompt can be enabled or disabled with the \f[B]BC_TTY_MODE\f[R] environment variable, the \f[B]-P\f[R] and \f[B]--no-prompt\f[R] options, and the \f[B]-R\f[R] and \f[B]--no-read-prompt\f[R] options. See the \f[B]ENVIRONMENT VARIABLES\f[R] and \f[B]OPTIONS\f[R] sections for more details. .SH SIGNAL HANDLING .PP Sending a \f[B]SIGINT\f[R] will cause bc(1) to do one of two things. .PP If bc(1) is not in interactive mode (see the \f[B]INTERACTIVE MODE\f[R] section), or the \f[B]BC_SIGINT_RESET\f[R] environment variable (see the \f[B]ENVIRONMENT VARIABLES\f[R] section), or its default, is either not an integer or it is zero, bc(1) will exit. .PP However, if bc(1) is in interactive mode, and the \f[B]BC_SIGINT_RESET\f[R] or its default is an integer and non-zero, then bc(1) will stop executing the current input and reset (see the \f[B]RESET\f[R] section) upon receiving a \f[B]SIGINT\f[R]. .PP Note that \[lq]current input\[rq] can mean one of two things. If bc(1) is processing input from \f[B]stdin\f[R] in interactive mode, it will ask for more input. If bc(1) is processing input from a file in interactive mode, it will stop processing the file and start processing the next file, if one exists, or ask for input from \f[B]stdin\f[R] if no other file exists. .PP This means that if a \f[B]SIGINT\f[R] is sent to bc(1) as it is executing a file, it can seem as though bc(1) did not respond to the signal since it will immediately start executing the next file. This is by design; most files that users execute when interacting with bc(1) have function definitions, which are quick to parse. If a file takes a long time to execute, there may be a bug in that file. The rest of the files could still be executed without problem, allowing the user to continue. .PP \f[B]SIGTERM\f[R] and \f[B]SIGQUIT\f[R] cause bc(1) to clean up and exit, and it uses the default handler for all other signals. .SH SEE ALSO .PP dc(1) .SH STANDARDS .PP bc(1) is compliant with the IEEE Std 1003.1-2017 (\[lq]POSIX.1-2017\[rq]) (https://pubs.opengroup.org/onlinepubs/9699919799/utilities/bc.html) specification. The flags \f[B]-efghiqsvVw\f[R], all long options, and the extensions noted above are extensions to that specification. .PP Note that the specification explicitly says that bc(1) only accepts numbers that use a period (\f[B].\f[R]) as a radix point, regardless of the value of \f[B]LC_NUMERIC\f[R]. .SH BUGS .PP None are known. Report bugs at https://git.yzena.com/gavin/bc. .SH AUTHORS .PP Gavin D. Howard and contributors. diff --git a/contrib/bc/manuals/bc/EHN.1.md b/contrib/bc/manuals/bc/EHN.1.md index 25543500eea7..3b60d3d0251b 100644 --- a/contrib/bc/manuals/bc/EHN.1.md +++ b/contrib/bc/manuals/bc/EHN.1.md @@ -1,1331 +1,1342 @@ # NAME bc - arbitrary-precision decimal arithmetic language and calculator # SYNOPSIS **bc** [**-ghilPqRsvVw**] [**-\-global-stacks**] [**-\-help**] [**-\-interactive**] [**-\-mathlib**] [**-\-no-prompt**] [**-\-no-read-prompt**] [**-\-quiet**] [**-\-standard**] [**-\-warn**] [**-\-version**] [**-e** *expr*] [**-\-expression**=*expr*...] [**-f** *file*...] [**-\-file**=*file*...] [*file*...] # DESCRIPTION bc(1) is an interactive processor for a language first standardized in 1991 by POSIX. (The current standard is [here][1].) The language provides unlimited precision decimal arithmetic and is somewhat C-like, but there are differences. Such differences will be noted in this document. After parsing and handling options, this bc(1) reads any files given on the command line and executes them before reading from **stdin**. This bc(1) is a drop-in replacement for *any* bc(1), including (and especially) the GNU bc(1). **Note**: If running this bc(1) on *any* script meant for another bc(1) gives a parse error, it is probably because a word this bc(1) reserves as a keyword is used as the name of a function, variable, or array. To fix that, use the command-line option **-r** *keyword*, where *keyword* is the keyword that is used as a name in the script. For more information, see the **OPTIONS** section. If parsing scripts meant for other bc(1) implementations still does not work, that is a bug and should be reported. See the **BUGS** section. # OPTIONS The following are the options that bc(1) accepts. **-g**, **-\-global-stacks** : Turns the globals **ibase**, **obase**, and **scale** into stacks. This has the effect that a copy of the current value of all three are pushed onto a stack for every function call, as well as popped when every function returns. This means that functions can assign to any and all of those globals without worrying that the change will affect other functions. Thus, a hypothetical function named **output(x,b)** that simply printed **x** in base **b** could be written like this: define void output(x, b) { obase=b x } instead of like this: define void output(x, b) { auto c c=obase obase=b x obase=c } This makes writing functions much easier. However, since using this flag means that functions cannot set **ibase**, **obase**, or **scale** globally, functions that are made to do so cannot work anymore. There are two possible use cases for that, and each has a solution. First, if a function is called on startup to turn bc(1) into a number converter, it is possible to replace that capability with various shell aliases. Examples: alias d2o="bc -e ibase=A -e obase=8" alias h2b="bc -e ibase=G -e obase=2" Second, if the purpose of a function is to set **ibase**, **obase**, or **scale** globally for any other purpose, it could be split into one to three functions (based on how many globals it sets) and each of those functions could return the desired value for a global. If the behavior of this option is desired for every run of bc(1), then users could make sure to define **BC_ENV_ARGS** and include this option (see the **ENVIRONMENT VARIABLES** section for more details). If **-s**, **-w**, or any equivalents are used, this option is ignored. This is a **non-portable extension**. **-h**, **-\-help** : Prints a usage message and quits. **-i**, **-\-interactive** : Forces interactive mode. (See the **INTERACTIVE MODE** section.) This is a **non-portable extension**. **-L**, **-\-no-line-length** : Disables line length checking and prints numbers without backslashes and newlines. In other words, this option sets **BC_LINE_LENGTH** to **0** (see the **ENVIRONMENT VARIABLES** section). This is a **non-portable extension**. **-l**, **-\-mathlib** : Sets **scale** (see the **SYNTAX** section) to **20** and loads the included math library before running any code, including any expressions or files specified on the command line. To learn what is in the library, see the **LIBRARY** section. **-P**, **-\-no-prompt** : Disables the prompt in TTY mode. (The prompt is only enabled in TTY mode. See the **TTY MODE** section.) This is mostly for those users that do not want a prompt or are not used to having them in bc(1). Most of those users would want to put this option in **BC_ENV_ARGS** (see the **ENVIRONMENT VARIABLES** section). These options override the **BC_PROMPT** and **BC_TTY_MODE** environment variables (see the **ENVIRONMENT VARIABLES** section). This is a **non-portable extension**. **-R**, **-\-no-read-prompt** : Disables the read prompt in TTY mode. (The read prompt is only enabled in TTY mode. See the **TTY MODE** section.) This is mostly for those users that do not want a read prompt or are not used to having them in bc(1). Most of those users would want to put this option in **BC_ENV_ARGS** (see the **ENVIRONMENT VARIABLES** section). This option is also useful in hash bang lines of bc(1) scripts that prompt for user input. This option does not disable the regular prompt because the read prompt is only used when the **read()** built-in function is called. These options *do* override the **BC_PROMPT** and **BC_TTY_MODE** environment variables (see the **ENVIRONMENT VARIABLES** section), but only for the read prompt. This is a **non-portable extension**. **-r** *keyword*, **-\-redefine**=*keyword* : Redefines *keyword* in order to allow it to be used as a function, variable, or array name. This is useful when this bc(1) gives parse errors when parsing scripts meant for other bc(1) implementations. The keywords this bc(1) allows to be redefined are: * **abs** * **asciify** * **continue** * **divmod** * **else** * **halt** * **last** * **limits** * **maxibase** * **maxobase** * **maxscale** * **modexp** * **print** * **read** * **stream** If any of those keywords are used as a function, variable, or array name in a script, use this option with the keyword as the argument. If multiple are used, use this option for all of them; it can be used multiple times. Keywords are *not* redefined when parsing the builtin math library (see the **LIBRARY** section). It is a fatal error to redefine keywords mandated by the POSIX standard. It is a fatal error to attempt to redefine words that this bc(1) does not reserve as keywords. **-q**, **-\-quiet** : This option is for compatibility with the [GNU bc(1)][2]; it is a no-op. Without this option, GNU bc(1) prints a copyright header. This bc(1) only prints the copyright header if one or more of the **-v**, **-V**, or **-\-version** options are given. This is a **non-portable extension**. **-s**, **-\-standard** : Process exactly the language defined by the [standard][1] and error if any extensions are used. This is a **non-portable extension**. **-v**, **-V**, **-\-version** : Print the version information (copyright header) and exit. This is a **non-portable extension**. **-w**, **-\-warn** : Like **-s** and **-\-standard**, except that warnings (and not errors) are printed for non-standard extensions and execution continues normally. This is a **non-portable extension**. **-z**, **-\-leading-zeroes** : Makes bc(1) print all numbers greater than **-1** and less than **1**, and not equal to **0**, with a leading zero. This can be set for individual numbers with the **plz(x)**, plznl(x)**, **pnlz(x)**, and **pnlznl(x)** functions in the extended math library (see the **LIBRARY** section). This is a **non-portable extension**. **-e** *expr*, **-\-expression**=*expr* : Evaluates *expr*. If multiple expressions are given, they are evaluated in order. If files are given as well (see below), the expressions and files are evaluated in the order given. This means that if a file is given before an expression, the file is read in and evaluated first. If this option is given on the command-line (i.e., not in **BC_ENV_ARGS**, see the **ENVIRONMENT VARIABLES** section), then after processing all expressions and files, bc(1) will exit, unless **-** (**stdin**) was given as an argument at least once to **-f** or **-\-file**, whether on the command-line or in **BC_ENV_ARGS**. However, if any other **-e**, **-\-expression**, **-f**, or **-\-file** arguments are given after **-f-** or equivalent is given, bc(1) will give a fatal error and exit. This is a **non-portable extension**. **-f** *file*, **-\-file**=*file* : Reads in *file* and evaluates it, line by line, as though it were read through **stdin**. If expressions are also given (see above), the expressions are evaluated in the order given. If this option is given on the command-line (i.e., not in **BC_ENV_ARGS**, see the **ENVIRONMENT VARIABLES** section), then after processing all expressions and files, bc(1) will exit, unless **-** (**stdin**) was given as an argument at least once to **-f** or **-\-file**. However, if any other **-e**, **-\-expression**, **-f**, or **-\-file** arguments are given after **-f-** or equivalent is given, bc(1) will give a fatal error and exit. This is a **non-portable extension**. All long options are **non-portable extensions**. # STDIN If no files or expressions are given by the **-f**, **-\-file**, **-e**, or **-\-expression** options, then bc(1) read from **stdin**. However, there are a few caveats to this. First, **stdin** is evaluated a line at a time. The only exception to this is if the parse cannot complete. That means that starting a string without ending it or starting a function, **if** statement, or loop without ending it will also cause bc(1) to not execute. Second, after an **if** statement, bc(1) doesn't know if an **else** statement will follow, so it will not execute until it knows there will not be an **else** statement. # STDOUT Any non-error output is written to **stdout**. In addition, if history (see the **HISTORY** section) and the prompt (see the **TTY MODE** section) are enabled, both are output to **stdout**. **Note**: Unlike other bc(1) implementations, this bc(1) will issue a fatal error (see the **EXIT STATUS** section) if it cannot write to **stdout**, so if **stdout** is closed, as in **bc >&-**, it will quit with an error. This is done so that bc(1) can report problems when **stdout** is redirected to a file. If there are scripts that depend on the behavior of other bc(1) implementations, it is recommended that those scripts be changed to redirect **stdout** to **/dev/null**. # STDERR Any error output is written to **stderr**. **Note**: Unlike other bc(1) implementations, this bc(1) will issue a fatal error (see the **EXIT STATUS** section) if it cannot write to **stderr**, so if **stderr** is closed, as in **bc 2>&-**, it will quit with an error. This is done so that bc(1) can exit with an error code when **stderr** is redirected to a file. If there are scripts that depend on the behavior of other bc(1) implementations, it is recommended that those scripts be changed to redirect **stderr** to **/dev/null**. # SYNTAX The syntax for bc(1) programs is mostly C-like, with some differences. This bc(1) follows the [POSIX standard][1], which is a much more thorough resource for the language this bc(1) accepts. This section is meant to be a summary and a listing of all the extensions to the standard. In the sections below, **E** means expression, **S** means statement, and **I** means identifier. Identifiers (**I**) start with a lowercase letter and can be followed by any number (up to **BC_NAME_MAX-1**) of lowercase letters (**a-z**), digits (**0-9**), and underscores (**\_**). The regex is **\[a-z\]\[a-z0-9\_\]\***. Identifiers with more than one character (letter) are a **non-portable extension**. **ibase** is a global variable determining how to interpret constant numbers. It is the "input" base, or the number base used for interpreting input numbers. **ibase** is initially **10**. If the **-s** (**-\-standard**) and **-w** (**-\-warn**) flags were not given on the command line, the max allowable value for **ibase** is **36**. Otherwise, it is **16**. The min allowable value for **ibase** is **2**. The max allowable value for **ibase** can be queried in bc(1) programs with the **maxibase()** built-in function. **obase** is a global variable determining how to output results. It is the "output" base, or the number base used for outputting numbers. **obase** is initially **10**. The max allowable value for **obase** is **BC_BASE_MAX** and can be queried in bc(1) programs with the **maxobase()** built-in function. The min allowable value for **obase** is **2**. Values are output in the specified base. The *scale* of an expression is the number of digits in the result of the expression right of the decimal point, and **scale** is a global variable that sets the precision of any operations, with exceptions. **scale** is initially **0**. **scale** cannot be negative. The max allowable value for **scale** is **BC_SCALE_MAX** and can be queried in bc(1) programs with the **maxscale()** built-in function. bc(1) has both *global* variables and *local* variables. All *local* variables are local to the function; they are parameters or are introduced in the **auto** list of a function (see the **FUNCTIONS** section). If a variable is accessed which is not a parameter or in the **auto** list, it is assumed to be *global*. If a parent function has a *local* variable version of a variable that a child function considers *global*, the value of that *global* variable in the child function is the value of the variable in the parent function, not the value of the actual *global* variable. All of the above applies to arrays as well. The value of a statement that is an expression (i.e., any of the named expressions or operands) is printed unless the lowest precedence operator is an assignment operator *and* the expression is notsurrounded by parentheses. The value that is printed is also assigned to the special variable **last**. A single dot (**.**) may also be used as a synonym for **last**. These are **non-portable extensions**. Either semicolons or newlines may separate statements. ## Comments There are two kinds of comments: 1. Block comments are enclosed in **/\*** and **\*/**. 2. Line comments go from **#** until, and not including, the next newline. This is a **non-portable extension**. ## Named Expressions The following are named expressions in bc(1): 1. Variables: **I** 2. Array Elements: **I[E]** 3. **ibase** 4. **obase** 5. **scale** 6. **last** or a single dot (**.**) Number 6 is a **non-portable extension**. Variables and arrays do not interfere; users can have arrays named the same as variables. This also applies to functions (see the **FUNCTIONS** section), so a user can have a variable, array, and function that all have the same name, and they will not shadow each other, whether inside of functions or not. Named expressions are required as the operand of **increment**/**decrement** operators and as the left side of **assignment** operators (see the *Operators* subsection). ## Operands The following are valid operands in bc(1): 1. Numbers (see the *Numbers* subsection below). 2. Array indices (**I[E]**). 3. **(E)**: The value of **E** (used to change precedence). 4. **sqrt(E)**: The square root of **E**. **E** must be non-negative. 5. **length(E)**: The number of significant decimal digits in **E**. Returns **1** for **0** with no decimal places. If given a string, the length of the string is returned. Passing a string to **length(E)** is a **non-portable extension**. 6. **length(I[])**: The number of elements in the array **I**. This is a **non-portable extension**. 7. **scale(E)**: The *scale* of **E**. 8. **abs(E)**: The absolute value of **E**. This is a **non-portable extension**. 9. **modexp(E, E, E)**: Modular exponentiation, where the first expression is the base, the second is the exponent, and the third is the modulus. All three values must be integers. The second argument must be non-negative. The third argument must be non-zero. This is a **non-portable extension**. 10. **divmod(E, E, I[])**: Division and modulus in one operation. This is for optimization. The first expression is the dividend, and the second is the divisor, which must be non-zero. The return value is the quotient, and the modulus is stored in index **0** of the provided array (the last argument). This is a **non-portable extension**. 11. **asciify(E)**: If **E** is a string, returns a string that is the first letter of its argument. If it is a number, calculates the number mod **256** and returns that number as a one-character string. This is a **non-portable extension**. 12. **I()**, **I(E)**, **I(E, E)**, and so on, where **I** is an identifier for a non-**void** function (see the *Void Functions* subsection of the **FUNCTIONS** section). The **E** argument(s) may also be arrays of the form **I[]**, which will automatically be turned into array references (see the *Array References* subsection of the **FUNCTIONS** section) if the corresponding parameter in the function definition is an array reference. 13. **read()**: Reads a line from **stdin** and uses that as an expression. The result of that expression is the result of the **read()** operand. This is a **non-portable extension**. 14. **maxibase()**: The max allowable **ibase**. This is a **non-portable extension**. 15. **maxobase()**: The max allowable **obase**. This is a **non-portable extension**. 16. **maxscale()**: The max allowable **scale**. This is a **non-portable extension**. 17. **line_length()**: The line length set with **BC_LINE_LENGTH** (see the **ENVIRONMENT VARIABLES** section). This is a **non-portable extension**. 18. **global_stacks()**: **0** if global stacks are not enabled with the **-g** or **-\-global-stacks** options, non-zero otherwise. See the **OPTIONS** section. This is a **non-portable extension**. 19. **leading_zero()**: **0** if leading zeroes are not enabled with the **-z** or **--leading-zeroes** options, non-zero otherwise. See the **OPTIONS** section. This is a **non-portable extension**. ## Numbers Numbers are strings made up of digits, uppercase letters, and at most **1** period for a radix. Numbers can have up to **BC_NUM_MAX** digits. Uppercase letters are equal to **9** + their position in the alphabet (i.e., **A** equals **10**, or **9+1**). If a digit or letter makes no sense with the current value of **ibase**, they are set to the value of the highest valid digit in **ibase**. Single-character numbers (i.e., **A** alone) take the value that they would have if they were valid digits, regardless of the value of **ibase**. This means that **A** alone always equals decimal **10** and **Z** alone always equals decimal **35**. ## Operators The following arithmetic and logical operators can be used. They are listed in order of decreasing precedence. Operators in the same group have the same precedence. **++** **-\-** : Type: Prefix and Postfix Associativity: None Description: **increment**, **decrement** **-** **!** : Type: Prefix Associativity: None Description: **negation**, **boolean not** **\^** : Type: Binary Associativity: Right Description: **power** **\*** **/** **%** : Type: Binary Associativity: Left Description: **multiply**, **divide**, **modulus** **+** **-** : Type: Binary Associativity: Left Description: **add**, **subtract** **=** **+=** **-=** **\*=** **/=** **%=** **\^=** : Type: Binary Associativity: Right Description: **assignment** **==** **\<=** **\>=** **!=** **\<** **\>** : Type: Binary Associativity: Left Description: **relational** **&&** : Type: Binary Associativity: Left Description: **boolean and** **||** : Type: Binary Associativity: Left Description: **boolean or** The operators will be described in more detail below. **++** **-\-** : The prefix and postfix **increment** and **decrement** operators behave exactly like they would in C. They require a named expression (see the *Named Expressions* subsection) as an operand. The prefix versions of these operators are more efficient; use them where possible. **-** : The **negation** operator returns **0** if a user attempts to negate any expression with the value **0**. Otherwise, a copy of the expression with its sign flipped is returned. **!** : The **boolean not** operator returns **1** if the expression is **0**, or **0** otherwise. This is a **non-portable extension**. **\^** : The **power** operator (not the **exclusive or** operator, as it would be in C) takes two expressions and raises the first to the power of the value of the second. The *scale* of the result is equal to **scale**. The second expression must be an integer (no *scale*), and if it is negative, the first value must be non-zero. **\*** : The **multiply** operator takes two expressions, multiplies them, and returns the product. If **a** is the *scale* of the first expression and **b** is the *scale* of the second expression, the *scale* of the result is equal to **min(a+b,max(scale,a,b))** where **min()** and **max()** return the obvious values. **/** : The **divide** operator takes two expressions, divides them, and returns the quotient. The *scale* of the result shall be the value of **scale**. The second expression must be non-zero. **%** : The **modulus** operator takes two expressions, **a** and **b**, and evaluates them by 1) Computing **a/b** to current **scale** and 2) Using the result of step 1 to calculate **a-(a/b)\*b** to *scale* **max(scale+scale(b),scale(a))**. The second expression must be non-zero. **+** : The **add** operator takes two expressions, **a** and **b**, and returns the sum, with a *scale* equal to the max of the *scale*s of **a** and **b**. **-** : The **subtract** operator takes two expressions, **a** and **b**, and returns the difference, with a *scale* equal to the max of the *scale*s of **a** and **b**. **=** **+=** **-=** **\*=** **/=** **%=** **\^=** : The **assignment** operators take two expressions, **a** and **b** where **a** is a named expression (see the *Named Expressions* subsection). For **=**, **b** is copied and the result is assigned to **a**. For all others, **a** and **b** are applied as operands to the corresponding arithmetic operator and the result is assigned to **a**. **==** **\<=** **\>=** **!=** **\<** **\>** : The **relational** operators compare two expressions, **a** and **b**, and if the relation holds, according to C language semantics, the result is **1**. Otherwise, it is **0**. Note that unlike in C, these operators have a lower precedence than the **assignment** operators, which means that **a=b\>c** is interpreted as **(a=b)\>c**. Also, unlike the [standard][1] requires, these operators can appear anywhere any other expressions can be used. This allowance is a **non-portable extension**. **&&** : The **boolean and** operator takes two expressions and returns **1** if both expressions are non-zero, **0** otherwise. This is *not* a short-circuit operator. This is a **non-portable extension**. **||** : The **boolean or** operator takes two expressions and returns **1** if one of the expressions is non-zero, **0** otherwise. This is *not* a short-circuit operator. This is a **non-portable extension**. ## Statements The following items are statements: 1. **E** 2. **{** **S** **;** ... **;** **S** **}** 3. **if** **(** **E** **)** **S** 4. **if** **(** **E** **)** **S** **else** **S** 5. **while** **(** **E** **)** **S** 6. **for** **(** **E** **;** **E** **;** **E** **)** **S** 7. An empty statement 8. **break** 9. **continue** 10. **quit** 11. **halt** 12. **limits** 13. A string of characters, enclosed in double quotes 14. **print** **E** **,** ... **,** **E** 15. **stream** **E** **,** ... **,** **E** 16. **I()**, **I(E)**, **I(E, E)**, and so on, where **I** is an identifier for a **void** function (see the *Void Functions* subsection of the **FUNCTIONS** section). The **E** argument(s) may also be arrays of the form **I[]**, which will automatically be turned into array references (see the *Array References* subsection of the **FUNCTIONS** section) if the corresponding parameter in the function definition is an array reference. Numbers 4, 9, 11, 12, 14, 15, and 16 are **non-portable extensions**. Also, as a **non-portable extension**, any or all of the expressions in the header of a for loop may be omitted. If the condition (second expression) is omitted, it is assumed to be a constant **1**. The **break** statement causes a loop to stop iterating and resume execution immediately following a loop. This is only allowed in loops. The **continue** statement causes a loop iteration to stop early and returns to the start of the loop, including testing the loop condition. This is only allowed in loops. The **if** **else** statement does the same thing as in C. The **quit** statement causes bc(1) to quit, even if it is on a branch that will not be executed (it is a compile-time command). The **halt** statement causes bc(1) to quit, if it is executed. (Unlike **quit** if it is on a branch of an **if** statement that is not executed, bc(1) does not quit.) The **limits** statement prints the limits that this bc(1) is subject to. This is like the **quit** statement in that it is a compile-time command. An expression by itself is evaluated and printed, followed by a newline. ## Strings If strings appear as a statement by themselves, they are printed without a trailing newline. In addition to appearing as a lone statement by themselves, strings can be assigned to variables and array elements. They can also be passed to functions in variable parameters. If any statement that expects a string is given a variable that had a string assigned to it, the statement acts as though it had received a string. If any math operation is attempted on a string or a variable or array element that has been assigned a string, an error is raised, and bc(1) resets (see the **RESET** section). Assigning strings to variables and array elements and passing them to functions are **non-portable extensions**. ## Print Statement The "expressions" in a **print** statement may also be strings. If they are, there are backslash escape sequences that are interpreted specially. What those sequences are, and what they cause to be printed, are shown below: **\\a**: **\\a** **\\b**: **\\b** **\\\\**: **\\** **\\e**: **\\** **\\f**: **\\f** **\\n**: **\\n** **\\q**: **"** **\\r**: **\\r** **\\t**: **\\t** Any other character following a backslash causes the backslash and character to be printed as-is. Any non-string expression in a print statement shall be assigned to **last**, like any other expression that is printed. ## Stream Statement The "expressions in a **stream** statement may also be strings. If a **stream** statement is given a string, it prints the string as though the string had appeared as its own statement. In other words, the **stream** statement prints strings normally, without a newline. If a **stream** statement is given a number, a copy of it is truncated and its absolute value is calculated. The result is then printed as though **obase** is **256** and each digit is interpreted as an 8-bit ASCII character, making it a byte stream. ## Order of Evaluation All expressions in a statment are evaluated left to right, except as necessary to maintain order of operations. This means, for example, assuming that **i** is equal to **0**, in the expression a[i++] = i++ the first (or 0th) element of **a** is set to **1**, and **i** is equal to **2** at the end of the expression. This includes function arguments. Thus, assuming **i** is equal to **0**, this means that in the expression x(i++, i++) the first argument passed to **x()** is **0**, and the second argument is **1**, while **i** is equal to **2** before the function starts executing. # FUNCTIONS Function definitions are as follows: ``` define I(I,...,I){ auto I,...,I S;...;S return(E) } ``` Any **I** in the parameter list or **auto** list may be replaced with **I[]** to make a parameter or **auto** var an array, and any **I** in the parameter list may be replaced with **\*I[]** to make a parameter an array reference. Callers of functions that take array references should not put an asterisk in the call; they must be called with just **I[]** like normal array parameters and will be automatically converted into references. As a **non-portable extension**, the opening brace of a **define** statement may appear on the next line. As a **non-portable extension**, the return statement may also be in one of the following forms: 1. **return** 2. **return** **(** **)** 3. **return** **E** The first two, or not specifying a **return** statement, is equivalent to **return (0)**, unless the function is a **void** function (see the *Void Functions* subsection below). ## Void Functions Functions can also be **void** functions, defined as follows: ``` define void I(I,...,I){ auto I,...,I S;...;S return } ``` They can only be used as standalone expressions, where such an expression would be printed alone, except in a print statement. Void functions can only use the first two **return** statements listed above. They can also omit the return statement entirely. The word "void" is not treated as a keyword; it is still possible to have variables, arrays, and functions named **void**. The word "void" is only treated specially right after the **define** keyword. This is a **non-portable extension**. ## Array References For any array in the parameter list, if the array is declared in the form ``` *I[] ``` it is a **reference**. Any changes to the array in the function are reflected, when the function returns, to the array that was passed in. Other than this, all function arguments are passed by value. This is a **non-portable extension**. # LIBRARY All of the functions below are available when the **-l** or **-\-mathlib** command-line flags are given. ## Standard Library The [standard][1] defines the following functions for the math library: **s(x)** : Returns the sine of **x**, which is assumed to be in radians. This is a transcendental function (see the *Transcendental Functions* subsection below). **c(x)** : Returns the cosine of **x**, which is assumed to be in radians. This is a transcendental function (see the *Transcendental Functions* subsection below). **a(x)** : Returns the arctangent of **x**, in radians. This is a transcendental function (see the *Transcendental Functions* subsection below). **l(x)** : Returns the natural logarithm of **x**. This is a transcendental function (see the *Transcendental Functions* subsection below). **e(x)** : Returns the mathematical constant **e** raised to the power of **x**. This is a transcendental function (see the *Transcendental Functions* subsection below). **j(x, n)** : Returns the bessel integer order **n** (truncated) of **x**. This is a transcendental function (see the *Transcendental Functions* subsection below). ## Transcendental Functions All transcendental functions can return slightly inaccurate results (up to 1 [ULP][4]). This is unavoidable, and [this article][5] explains why it is impossible and unnecessary to calculate exact results for the transcendental functions. Because of the possible inaccuracy, I recommend that users call those functions with the precision (**scale**) set to at least 1 higher than is necessary. If exact results are *absolutely* required, users can double the precision (**scale**) and then truncate. The transcendental functions in the standard math library are: * **s(x)** * **c(x)** * **a(x)** * **l(x)** * **e(x)** * **j(x, n)** # RESET When bc(1) encounters an error or a signal that it has a non-default handler for, it resets. This means that several things happen. First, any functions that are executing are stopped and popped off the stack. The behavior is not unlike that of exceptions in programming languages. Then the execution point is set so that any code waiting to execute (after all functions returned) is skipped. Thus, when bc(1) resets, it skips any remaining code waiting to be executed. Then, if it is interactive mode, and the error was not a fatal error (see the **EXIT STATUS** section), it asks for more input; otherwise, it exits with the appropriate return code. Note that this reset behavior is different from the GNU bc(1), which attempts to start executing the statement right after the one that caused an error. # PERFORMANCE Most bc(1) implementations use **char** types to calculate the value of **1** decimal digit at a time, but that can be slow. This bc(1) does something different. It uses large integers to calculate more than **1** decimal digit at a time. If built in a environment where **BC_LONG_BIT** (see the **LIMITS** section) is **64**, then each integer has **9** decimal digits. If built in an environment where **BC_LONG_BIT** is **32** then each integer has **4** decimal digits. This value (the number of decimal digits per large integer) is called **BC_BASE_DIGS**. The actual values of **BC_LONG_BIT** and **BC_BASE_DIGS** can be queried with the **limits** statement. In addition, this bc(1) uses an even larger integer for overflow checking. This integer type depends on the value of **BC_LONG_BIT**, but is always at least twice as large as the integer type used to store digits. # LIMITS The following are the limits on bc(1): **BC_LONG_BIT** : The number of bits in the **long** type in the environment where bc(1) was built. This determines how many decimal digits can be stored in a single large integer (see the **PERFORMANCE** section). **BC_BASE_DIGS** : The number of decimal digits per large integer (see the **PERFORMANCE** section). Depends on **BC_LONG_BIT**. **BC_BASE_POW** : The max decimal number that each large integer can store (see **BC_BASE_DIGS**) plus **1**. Depends on **BC_BASE_DIGS**. **BC_OVERFLOW_MAX** : The max number that the overflow type (see the **PERFORMANCE** section) can hold. Depends on **BC_LONG_BIT**. **BC_BASE_MAX** : The maximum output base. Set at **BC_BASE_POW**. **BC_DIM_MAX** : The maximum size of arrays. Set at **SIZE_MAX-1**. **BC_SCALE_MAX** : The maximum **scale**. Set at **BC_OVERFLOW_MAX-1**. **BC_STRING_MAX** : The maximum length of strings. Set at **BC_OVERFLOW_MAX-1**. **BC_NAME_MAX** : The maximum length of identifiers. Set at **BC_OVERFLOW_MAX-1**. **BC_NUM_MAX** : The maximum length of a number (in decimal digits), which includes digits after the decimal point. Set at **BC_OVERFLOW_MAX-1**. Exponent : The maximum allowable exponent (positive or negative). Set at **BC_OVERFLOW_MAX**. Number of vars : The maximum number of vars/arrays. Set at **SIZE_MAX-1**. The actual values can be queried with the **limits** statement. These limits are meant to be effectively non-existent; the limits are so large (at least on 64-bit machines) that there should not be any point at which they become a problem. In fact, memory should be exhausted before these limits should be hit. # ENVIRONMENT VARIABLES bc(1) recognizes the following environment variables: **POSIXLY_CORRECT** : If this variable exists (no matter the contents), bc(1) behaves as if the **-s** option was given. **BC_ENV_ARGS** : This is another way to give command-line arguments to bc(1). They should be in the same format as all other command-line arguments. These are always processed first, so any files given in **BC_ENV_ARGS** will be processed before arguments and files given on the command-line. This gives the user the ability to set up "standard" options and files to be used at every invocation. The most useful thing for such files to contain would be useful functions that the user might want every time bc(1) runs. The code that parses **BC_ENV_ARGS** will correctly handle quoted arguments, but it does not understand escape sequences. For example, the string **"/home/gavin/some bc file.bc"** will be correctly parsed, but the string **"/home/gavin/some \"bc\" file.bc"** will include the backslashes. The quote parsing will handle either kind of quotes, **'** or **"**. Thus, if you have a file with any number of single quotes in the name, you can use double quotes as the outside quotes, as in **"some 'bc' file.bc"**, and vice versa if you have a file with double quotes. However, handling a file with both kinds of quotes in **BC_ENV_ARGS** is not supported due to the complexity of the parsing, though such files are still supported on the command-line where the parsing is done by the shell. **BC_LINE_LENGTH** : If this environment variable exists and contains an integer that is greater than **1** and is less than **UINT16_MAX** (**2\^16-1**), bc(1) will output lines to that length, including the backslash (**\\**). The default line length is **70**. The special value of **0** will disable line length checking and print numbers without regard to line length and without backslashes and newlines. **BC_BANNER** : If this environment variable exists and contains an integer, then a non-zero value activates the copyright banner when bc(1) is in interactive mode, while zero deactivates it. If bc(1) is not in interactive mode (see the **INTERACTIVE MODE** section), then this environment variable has no effect because bc(1) does not print the banner when not in interactive mode. This environment variable overrides the default, which can be queried with the **-h** or **-\-help** options. **BC_SIGINT_RESET** : If bc(1) is not in interactive mode (see the **INTERACTIVE MODE** section), then this environment variable has no effect because bc(1) exits on **SIGINT** when not in interactive mode. However, when bc(1) is in interactive mode, then if this environment variable exists and contains an integer, a non-zero value makes bc(1) reset on **SIGINT**, rather than exit, and zero makes bc(1) exit. If this environment variable exists and is *not* an integer, then bc(1) will exit on **SIGINT**. This environment variable overrides the default, which can be queried with the **-h** or **-\-help** options. **BC_TTY_MODE** : If TTY mode is *not* available (see the **TTY MODE** section), then this environment variable has no effect. However, when TTY mode is available, then if this environment variable exists and contains an integer, then a non-zero value makes bc(1) use TTY mode, and zero makes bc(1) not use TTY mode. This environment variable overrides the default, which can be queried with the **-h** or **-\-help** options. **BC_PROMPT** : If TTY mode is *not* available (see the **TTY MODE** section), then this environment variable has no effect. However, when TTY mode is available, then if this environment variable exists and contains an integer, a non-zero value makes bc(1) use a prompt, and zero or a non-integer makes bc(1) not use a prompt. If this environment variable does not exist and **BC_TTY_MODE** does, then the value of the **BC_TTY_MODE** environment variable is used. This environment variable and the **BC_TTY_MODE** environment variable override the default, which can be queried with the **-h** or **-\-help** options. +**BC_EXPR_EXIT** + +: If any expressions or expression files are given on the command-line with + **-e**, **-\-expression**, **-f**, or **-\-file**, then if this environment + variable exists and contains an integer, a non-zero value makes bc(1) exit + after executing the expressions and expression files, and a non-zero value + makes bc(1) not exit. + + This environment variable overrides the default, which can be queried with + the **-h** or **-\-help** options. + # EXIT STATUS bc(1) returns the following exit statuses: **0** : No error. **1** : A math error occurred. This follows standard practice of using **1** for expected errors, since math errors will happen in the process of normal execution. Math errors include divide by **0**, taking the square root of a negative number, attempting to convert a negative number to a hardware integer, overflow when converting a number to a hardware integer, overflow when calculating the size of a number, and attempting to use a non-integer where an integer is required. Converting to a hardware integer happens for the second operand of the power (**\^**) operator and the corresponding assignment operator. **2** : A parse error occurred. Parse errors include unexpected **EOF**, using an invalid character, failing to find the end of a string or comment, using a token where it is invalid, giving an invalid expression, giving an invalid print statement, giving an invalid function definition, attempting to assign to an expression that is not a named expression (see the *Named Expressions* subsection of the **SYNTAX** section), giving an invalid **auto** list, having a duplicate **auto**/function parameter, failing to find the end of a code block, attempting to return a value from a **void** function, attempting to use a variable as a reference, and using any extensions when the option **-s** or any equivalents were given. **3** : A runtime error occurred. Runtime errors include assigning an invalid number to any global (**ibase**, **obase**, or **scale**), giving a bad expression to a **read()** call, calling **read()** inside of a **read()** call, type errors, passing the wrong number of arguments to functions, attempting to call an undefined function, and attempting to use a **void** function call as a value in an expression. **4** : A fatal error occurred. Fatal errors include memory allocation errors, I/O errors, failing to open files, attempting to use files that do not have only ASCII characters (bc(1) only accepts ASCII characters), attempting to open a directory as a file, and giving invalid command-line options. The exit status **4** is special; when a fatal error occurs, bc(1) always exits and returns **4**, no matter what mode bc(1) is in. The other statuses will only be returned when bc(1) is not in interactive mode (see the **INTERACTIVE MODE** section), since bc(1) resets its state (see the **RESET** section) and accepts more input when one of those errors occurs in interactive mode. This is also the case when interactive mode is forced by the **-i** flag or **-\-interactive** option. These exit statuses allow bc(1) to be used in shell scripting with error checking, and its normal behavior can be forced by using the **-i** flag or **-\-interactive** option. # INTERACTIVE MODE Per the [standard][1], bc(1) has an interactive mode and a non-interactive mode. Interactive mode is turned on automatically when both **stdin** and **stdout** are hooked to a terminal, but the **-i** flag and **-\-interactive** option can turn it on in other situations. In interactive mode, bc(1) attempts to recover from errors (see the **RESET** section), and in normal execution, flushes **stdout** as soon as execution is done for the current input. bc(1) may also reset on **SIGINT** instead of exit, depending on the contents of, or default for, the **BC_SIGINT_RESET** environment variable (see the **ENVIRONMENT VARIABLES** section). # TTY MODE If **stdin**, **stdout**, and **stderr** are all connected to a TTY, then "TTY mode" is considered to be available, and thus, bc(1) can turn on TTY mode, subject to some settings. If there is the environment variable **BC_TTY_MODE** in the environment (see the **ENVIRONMENT VARIABLES** section), then if that environment variable contains a non-zero integer, bc(1) will turn on TTY mode when **stdin**, **stdout**, and **stderr** are all connected to a TTY. If the **BC_TTY_MODE** environment variable exists but is *not* a non-zero integer, then bc(1) will not turn TTY mode on. If the environment variable **BC_TTY_MODE** does *not* exist, the default setting is used. The default setting can be queried with the **-h** or **-\-help** options. TTY mode is different from interactive mode because interactive mode is required in the [bc(1) specification][1], and interactive mode requires only **stdin** and **stdout** to be connected to a terminal. ## Prompt If TTY mode is available, then a prompt can be enabled. Like TTY mode itself, it can be turned on or off with an environment variable: **BC_PROMPT** (see the **ENVIRONMENT VARIABLES** section). If the environment variable **BC_PROMPT** exists and is a non-zero integer, then the prompt is turned on when **stdin**, **stdout**, and **stderr** are connected to a TTY and the **-P** and **-\-no-prompt** options were not used. The read prompt will be turned on under the same conditions, except that the **-R** and **-\-no-read-prompt** options must also not be used. However, if **BC_PROMPT** does not exist, the prompt can be enabled or disabled with the **BC_TTY_MODE** environment variable, the **-P** and **-\-no-prompt** options, and the **-R** and **-\-no-read-prompt** options. See the **ENVIRONMENT VARIABLES** and **OPTIONS** sections for more details. # SIGNAL HANDLING Sending a **SIGINT** will cause bc(1) to do one of two things. If bc(1) is not in interactive mode (see the **INTERACTIVE MODE** section), or the **BC_SIGINT_RESET** environment variable (see the **ENVIRONMENT VARIABLES** section), or its default, is either not an integer or it is zero, bc(1) will exit. However, if bc(1) is in interactive mode, and the **BC_SIGINT_RESET** or its default is an integer and non-zero, then bc(1) will stop executing the current input and reset (see the **RESET** section) upon receiving a **SIGINT**. Note that "current input" can mean one of two things. If bc(1) is processing input from **stdin** in interactive mode, it will ask for more input. If bc(1) is processing input from a file in interactive mode, it will stop processing the file and start processing the next file, if one exists, or ask for input from **stdin** if no other file exists. This means that if a **SIGINT** is sent to bc(1) as it is executing a file, it can seem as though bc(1) did not respond to the signal since it will immediately start executing the next file. This is by design; most files that users execute when interacting with bc(1) have function definitions, which are quick to parse. If a file takes a long time to execute, there may be a bug in that file. The rest of the files could still be executed without problem, allowing the user to continue. **SIGTERM** and **SIGQUIT** cause bc(1) to clean up and exit, and it uses the default handler for all other signals. # SEE ALSO dc(1) # STANDARDS bc(1) is compliant with the [IEEE Std 1003.1-2017 (“POSIX.1-2017”)][1] specification. The flags **-efghiqsvVw**, all long options, and the extensions noted above are extensions to that specification. Note that the specification explicitly says that bc(1) only accepts numbers that use a period (**.**) as a radix point, regardless of the value of **LC_NUMERIC**. # BUGS None are known. Report bugs at https://git.yzena.com/gavin/bc. # AUTHORS Gavin D. Howard and contributors. [1]: https://pubs.opengroup.org/onlinepubs/9699919799/utilities/bc.html [2]: https://www.gnu.org/software/bc/ [3]: https://en.wikipedia.org/wiki/Rounding#Round_half_away_from_zero [4]: https://en.wikipedia.org/wiki/Unit_in_the_last_place [5]: https://people.eecs.berkeley.edu/~wkahan/LOG10HAF.TXT [6]: https://en.wikipedia.org/wiki/Rounding#Rounding_away_from_zero diff --git a/contrib/bc/manuals/bc/EN.1 b/contrib/bc/manuals/bc/EN.1 index 192dccfea2fc..c4704807fac6 100644 --- a/contrib/bc/manuals/bc/EN.1 +++ b/contrib/bc/manuals/bc/EN.1 @@ -1,1623 +1,1636 @@ .\" .\" SPDX-License-Identifier: BSD-2-Clause .\" .\" Copyright (c) 2018-2021 Gavin D. Howard and contributors. .\" .\" Redistribution and use in source and binary forms, with or without .\" modification, are permitted provided that the following conditions are met: .\" .\" * Redistributions of source code must retain the above copyright notice, .\" this list of conditions and the following disclaimer. .\" .\" * Redistributions in binary form must reproduce the above copyright notice, .\" this list of conditions and the following disclaimer in the documentation .\" and/or other materials provided with the distribution. .\" .\" THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" .\" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE .\" IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE .\" ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE .\" LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR .\" CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF .\" SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS .\" INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN .\" CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) .\" ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE .\" POSSIBILITY OF SUCH DAMAGE. .\" .TH "BC" "1" "June 2021" "Gavin D. Howard" "General Commands Manual" .SH NAME .PP bc - arbitrary-precision decimal arithmetic language and calculator .SH SYNOPSIS .PP \f[B]bc\f[R] [\f[B]-ghilPqRsvVw\f[R]] [\f[B]--global-stacks\f[R]] [\f[B]--help\f[R]] [\f[B]--interactive\f[R]] [\f[B]--mathlib\f[R]] [\f[B]--no-prompt\f[R]] [\f[B]--no-read-prompt\f[R]] [\f[B]--quiet\f[R]] [\f[B]--standard\f[R]] [\f[B]--warn\f[R]] [\f[B]--version\f[R]] [\f[B]-e\f[R] \f[I]expr\f[R]] [\f[B]--expression\f[R]=\f[I]expr\f[R]\&...] [\f[B]-f\f[R] \f[I]file\f[R]\&...] [\f[B]--file\f[R]=\f[I]file\f[R]\&...] [\f[I]file\f[R]\&...] .SH DESCRIPTION .PP bc(1) is an interactive processor for a language first standardized in 1991 by POSIX. (The current standard is here (https://pubs.opengroup.org/onlinepubs/9699919799/utilities/bc.html).) The language provides unlimited precision decimal arithmetic and is somewhat C-like, but there are differences. Such differences will be noted in this document. .PP After parsing and handling options, this bc(1) reads any files given on the command line and executes them before reading from \f[B]stdin\f[R]. .PP This bc(1) is a drop-in replacement for \f[I]any\f[R] bc(1), including (and especially) the GNU bc(1). .PP \f[B]Note\f[R]: If running this bc(1) on \f[I]any\f[R] script meant for another bc(1) gives a parse error, it is probably because a word this bc(1) reserves as a keyword is used as the name of a function, variable, or array. To fix that, use the command-line option \f[B]-r\f[R] \f[I]keyword\f[R], where \f[I]keyword\f[R] is the keyword that is used as a name in the script. For more information, see the \f[B]OPTIONS\f[R] section. .PP If parsing scripts meant for other bc(1) implementations still does not work, that is a bug and should be reported. See the \f[B]BUGS\f[R] section. .SH OPTIONS .PP The following are the options that bc(1) accepts. .TP \f[B]-g\f[R], \f[B]--global-stacks\f[R] Turns the globals \f[B]ibase\f[R], \f[B]obase\f[R], and \f[B]scale\f[R] into stacks. .RS .PP This has the effect that a copy of the current value of all three are pushed onto a stack for every function call, as well as popped when every function returns. This means that functions can assign to any and all of those globals without worrying that the change will affect other functions. Thus, a hypothetical function named \f[B]output(x,b)\f[R] that simply printed \f[B]x\f[R] in base \f[B]b\f[R] could be written like this: .IP .nf \f[C] define void output(x, b) { obase=b x } \f[R] .fi .PP instead of like this: .IP .nf \f[C] define void output(x, b) { auto c c=obase obase=b x obase=c } \f[R] .fi .PP This makes writing functions much easier. .PP However, since using this flag means that functions cannot set \f[B]ibase\f[R], \f[B]obase\f[R], or \f[B]scale\f[R] globally, functions that are made to do so cannot work anymore. There are two possible use cases for that, and each has a solution. .PP First, if a function is called on startup to turn bc(1) into a number converter, it is possible to replace that capability with various shell aliases. Examples: .IP .nf \f[C] alias d2o=\[dq]bc -e ibase=A -e obase=8\[dq] alias h2b=\[dq]bc -e ibase=G -e obase=2\[dq] \f[R] .fi .PP Second, if the purpose of a function is to set \f[B]ibase\f[R], \f[B]obase\f[R], or \f[B]scale\f[R] globally for any other purpose, it could be split into one to three functions (based on how many globals it sets) and each of those functions could return the desired value for a global. .PP If the behavior of this option is desired for every run of bc(1), then users could make sure to define \f[B]BC_ENV_ARGS\f[R] and include this option (see the \f[B]ENVIRONMENT VARIABLES\f[R] section for more details). .PP If \f[B]-s\f[R], \f[B]-w\f[R], or any equivalents are used, this option is ignored. .PP This is a \f[B]non-portable extension\f[R]. .RE .TP \f[B]-h\f[R], \f[B]--help\f[R] Prints a usage message and quits. .TP \f[B]-i\f[R], \f[B]--interactive\f[R] Forces interactive mode. (See the \f[B]INTERACTIVE MODE\f[R] section.) .RS .PP This is a \f[B]non-portable extension\f[R]. .RE .TP \f[B]-L\f[R], \f[B]--no-line-length\f[R] Disables line length checking and prints numbers without backslashes and newlines. In other words, this option sets \f[B]BC_LINE_LENGTH\f[R] to \f[B]0\f[R] (see the \f[B]ENVIRONMENT VARIABLES\f[R] section). .RS .PP This is a \f[B]non-portable extension\f[R]. .RE .TP \f[B]-l\f[R], \f[B]--mathlib\f[R] Sets \f[B]scale\f[R] (see the \f[B]SYNTAX\f[R] section) to \f[B]20\f[R] and loads the included math library before running any code, including any expressions or files specified on the command line. .RS .PP To learn what is in the library, see the \f[B]LIBRARY\f[R] section. .RE .TP \f[B]-P\f[R], \f[B]--no-prompt\f[R] Disables the prompt in TTY mode. (The prompt is only enabled in TTY mode. See the \f[B]TTY MODE\f[R] section.) This is mostly for those users that do not want a prompt or are not used to having them in bc(1). Most of those users would want to put this option in \f[B]BC_ENV_ARGS\f[R] (see the \f[B]ENVIRONMENT VARIABLES\f[R] section). .RS .PP These options override the \f[B]BC_PROMPT\f[R] and \f[B]BC_TTY_MODE\f[R] environment variables (see the \f[B]ENVIRONMENT VARIABLES\f[R] section). .PP This is a \f[B]non-portable extension\f[R]. .RE .TP \f[B]-R\f[R], \f[B]--no-read-prompt\f[R] Disables the read prompt in TTY mode. (The read prompt is only enabled in TTY mode. See the \f[B]TTY MODE\f[R] section.) This is mostly for those users that do not want a read prompt or are not used to having them in bc(1). Most of those users would want to put this option in \f[B]BC_ENV_ARGS\f[R] (see the \f[B]ENVIRONMENT VARIABLES\f[R] section). This option is also useful in hash bang lines of bc(1) scripts that prompt for user input. .RS .PP This option does not disable the regular prompt because the read prompt is only used when the \f[B]read()\f[R] built-in function is called. .PP These options \f[I]do\f[R] override the \f[B]BC_PROMPT\f[R] and \f[B]BC_TTY_MODE\f[R] environment variables (see the \f[B]ENVIRONMENT VARIABLES\f[R] section), but only for the read prompt. .PP This is a \f[B]non-portable extension\f[R]. .RE .TP \f[B]-r\f[R] \f[I]keyword\f[R], \f[B]--redefine\f[R]=\f[I]keyword\f[R] Redefines \f[I]keyword\f[R] in order to allow it to be used as a function, variable, or array name. This is useful when this bc(1) gives parse errors when parsing scripts meant for other bc(1) implementations. .RS .PP The keywords this bc(1) allows to be redefined are: .IP \[bu] 2 \f[B]abs\f[R] .IP \[bu] 2 \f[B]asciify\f[R] .IP \[bu] 2 \f[B]continue\f[R] .IP \[bu] 2 \f[B]divmod\f[R] .IP \[bu] 2 \f[B]else\f[R] .IP \[bu] 2 \f[B]halt\f[R] .IP \[bu] 2 \f[B]last\f[R] .IP \[bu] 2 \f[B]limits\f[R] .IP \[bu] 2 \f[B]maxibase\f[R] .IP \[bu] 2 \f[B]maxobase\f[R] .IP \[bu] 2 \f[B]maxscale\f[R] .IP \[bu] 2 \f[B]modexp\f[R] .IP \[bu] 2 \f[B]print\f[R] .IP \[bu] 2 \f[B]read\f[R] .IP \[bu] 2 \f[B]stream\f[R] .PP If any of those keywords are used as a function, variable, or array name in a script, use this option with the keyword as the argument. If multiple are used, use this option for all of them; it can be used multiple times. .PP Keywords are \f[I]not\f[R] redefined when parsing the builtin math library (see the \f[B]LIBRARY\f[R] section). .PP It is a fatal error to redefine keywords mandated by the POSIX standard. It is a fatal error to attempt to redefine words that this bc(1) does not reserve as keywords. .RE .TP \f[B]-q\f[R], \f[B]--quiet\f[R] This option is for compatibility with the GNU bc(1) (https://www.gnu.org/software/bc/); it is a no-op. Without this option, GNU bc(1) prints a copyright header. This bc(1) only prints the copyright header if one or more of the \f[B]-v\f[R], \f[B]-V\f[R], or \f[B]--version\f[R] options are given. .RS .PP This is a \f[B]non-portable extension\f[R]. .RE .TP \f[B]-s\f[R], \f[B]--standard\f[R] Process exactly the language defined by the standard (https://pubs.opengroup.org/onlinepubs/9699919799/utilities/bc.html) and error if any extensions are used. .RS .PP This is a \f[B]non-portable extension\f[R]. .RE .TP \f[B]-v\f[R], \f[B]-V\f[R], \f[B]--version\f[R] Print the version information (copyright header) and exit. .RS .PP This is a \f[B]non-portable extension\f[R]. .RE .TP \f[B]-w\f[R], \f[B]--warn\f[R] Like \f[B]-s\f[R] and \f[B]--standard\f[R], except that warnings (and not errors) are printed for non-standard extensions and execution continues normally. .RS .PP This is a \f[B]non-portable extension\f[R]. .RE .TP \f[B]-z\f[R], \f[B]--leading-zeroes\f[R] Makes bc(1) print all numbers greater than \f[B]-1\f[R] and less than \f[B]1\f[R], and not equal to \f[B]0\f[R], with a leading zero. .RS .PP This can be set for individual numbers with the \f[B]plz(x)\f[R], plznl(x)**, \f[B]pnlz(x)\f[R], and \f[B]pnlznl(x)\f[R] functions in the extended math library (see the \f[B]LIBRARY\f[R] section). .PP This is a \f[B]non-portable extension\f[R]. .RE .TP \f[B]-e\f[R] \f[I]expr\f[R], \f[B]--expression\f[R]=\f[I]expr\f[R] Evaluates \f[I]expr\f[R]. If multiple expressions are given, they are evaluated in order. If files are given as well (see below), the expressions and files are evaluated in the order given. This means that if a file is given before an expression, the file is read in and evaluated first. .RS .PP If this option is given on the command-line (i.e., not in \f[B]BC_ENV_ARGS\f[R], see the \f[B]ENVIRONMENT VARIABLES\f[R] section), then after processing all expressions and files, bc(1) will exit, unless \f[B]-\f[R] (\f[B]stdin\f[R]) was given as an argument at least once to \f[B]-f\f[R] or \f[B]--file\f[R], whether on the command-line or in \f[B]BC_ENV_ARGS\f[R]. However, if any other \f[B]-e\f[R], \f[B]--expression\f[R], \f[B]-f\f[R], or \f[B]--file\f[R] arguments are given after \f[B]-f-\f[R] or equivalent is given, bc(1) will give a fatal error and exit. .PP This is a \f[B]non-portable extension\f[R]. .RE .TP \f[B]-f\f[R] \f[I]file\f[R], \f[B]--file\f[R]=\f[I]file\f[R] Reads in \f[I]file\f[R] and evaluates it, line by line, as though it were read through \f[B]stdin\f[R]. If expressions are also given (see above), the expressions are evaluated in the order given. .RS .PP If this option is given on the command-line (i.e., not in \f[B]BC_ENV_ARGS\f[R], see the \f[B]ENVIRONMENT VARIABLES\f[R] section), then after processing all expressions and files, bc(1) will exit, unless \f[B]-\f[R] (\f[B]stdin\f[R]) was given as an argument at least once to \f[B]-f\f[R] or \f[B]--file\f[R]. However, if any other \f[B]-e\f[R], \f[B]--expression\f[R], \f[B]-f\f[R], or \f[B]--file\f[R] arguments are given after \f[B]-f-\f[R] or equivalent is given, bc(1) will give a fatal error and exit. .PP This is a \f[B]non-portable extension\f[R]. .RE .PP All long options are \f[B]non-portable extensions\f[R]. .SH STDIN .PP If no files or expressions are given by the \f[B]-f\f[R], \f[B]--file\f[R], \f[B]-e\f[R], or \f[B]--expression\f[R] options, then bc(1) read from \f[B]stdin\f[R]. .PP However, there are a few caveats to this. .PP First, \f[B]stdin\f[R] is evaluated a line at a time. The only exception to this is if the parse cannot complete. That means that starting a string without ending it or starting a function, \f[B]if\f[R] statement, or loop without ending it will also cause bc(1) to not execute. .PP Second, after an \f[B]if\f[R] statement, bc(1) doesn\[cq]t know if an \f[B]else\f[R] statement will follow, so it will not execute until it knows there will not be an \f[B]else\f[R] statement. .SH STDOUT .PP Any non-error output is written to \f[B]stdout\f[R]. In addition, if history (see the \f[B]HISTORY\f[R] section) and the prompt (see the \f[B]TTY MODE\f[R] section) are enabled, both are output to \f[B]stdout\f[R]. .PP \f[B]Note\f[R]: Unlike other bc(1) implementations, this bc(1) will issue a fatal error (see the \f[B]EXIT STATUS\f[R] section) if it cannot write to \f[B]stdout\f[R], so if \f[B]stdout\f[R] is closed, as in \f[B]bc >&-\f[R], it will quit with an error. This is done so that bc(1) can report problems when \f[B]stdout\f[R] is redirected to a file. .PP If there are scripts that depend on the behavior of other bc(1) implementations, it is recommended that those scripts be changed to redirect \f[B]stdout\f[R] to \f[B]/dev/null\f[R]. .SH STDERR .PP Any error output is written to \f[B]stderr\f[R]. .PP \f[B]Note\f[R]: Unlike other bc(1) implementations, this bc(1) will issue a fatal error (see the \f[B]EXIT STATUS\f[R] section) if it cannot write to \f[B]stderr\f[R], so if \f[B]stderr\f[R] is closed, as in \f[B]bc 2>&-\f[R], it will quit with an error. This is done so that bc(1) can exit with an error code when \f[B]stderr\f[R] is redirected to a file. .PP If there are scripts that depend on the behavior of other bc(1) implementations, it is recommended that those scripts be changed to redirect \f[B]stderr\f[R] to \f[B]/dev/null\f[R]. .SH SYNTAX .PP The syntax for bc(1) programs is mostly C-like, with some differences. This bc(1) follows the POSIX standard (https://pubs.opengroup.org/onlinepubs/9699919799/utilities/bc.html), which is a much more thorough resource for the language this bc(1) accepts. This section is meant to be a summary and a listing of all the extensions to the standard. .PP In the sections below, \f[B]E\f[R] means expression, \f[B]S\f[R] means statement, and \f[B]I\f[R] means identifier. .PP Identifiers (\f[B]I\f[R]) start with a lowercase letter and can be followed by any number (up to \f[B]BC_NAME_MAX-1\f[R]) of lowercase letters (\f[B]a-z\f[R]), digits (\f[B]0-9\f[R]), and underscores (\f[B]_\f[R]). The regex is \f[B][a-z][a-z0-9_]*\f[R]. Identifiers with more than one character (letter) are a \f[B]non-portable extension\f[R]. .PP \f[B]ibase\f[R] is a global variable determining how to interpret constant numbers. It is the \[lq]input\[rq] base, or the number base used for interpreting input numbers. \f[B]ibase\f[R] is initially \f[B]10\f[R]. If the \f[B]-s\f[R] (\f[B]--standard\f[R]) and \f[B]-w\f[R] (\f[B]--warn\f[R]) flags were not given on the command line, the max allowable value for \f[B]ibase\f[R] is \f[B]36\f[R]. Otherwise, it is \f[B]16\f[R]. The min allowable value for \f[B]ibase\f[R] is \f[B]2\f[R]. The max allowable value for \f[B]ibase\f[R] can be queried in bc(1) programs with the \f[B]maxibase()\f[R] built-in function. .PP \f[B]obase\f[R] is a global variable determining how to output results. It is the \[lq]output\[rq] base, or the number base used for outputting numbers. \f[B]obase\f[R] is initially \f[B]10\f[R]. The max allowable value for \f[B]obase\f[R] is \f[B]BC_BASE_MAX\f[R] and can be queried in bc(1) programs with the \f[B]maxobase()\f[R] built-in function. The min allowable value for \f[B]obase\f[R] is \f[B]2\f[R]. Values are output in the specified base. .PP The \f[I]scale\f[R] of an expression is the number of digits in the result of the expression right of the decimal point, and \f[B]scale\f[R] is a global variable that sets the precision of any operations, with exceptions. \f[B]scale\f[R] is initially \f[B]0\f[R]. \f[B]scale\f[R] cannot be negative. The max allowable value for \f[B]scale\f[R] is \f[B]BC_SCALE_MAX\f[R] and can be queried in bc(1) programs with the \f[B]maxscale()\f[R] built-in function. .PP bc(1) has both \f[I]global\f[R] variables and \f[I]local\f[R] variables. All \f[I]local\f[R] variables are local to the function; they are parameters or are introduced in the \f[B]auto\f[R] list of a function (see the \f[B]FUNCTIONS\f[R] section). If a variable is accessed which is not a parameter or in the \f[B]auto\f[R] list, it is assumed to be \f[I]global\f[R]. If a parent function has a \f[I]local\f[R] variable version of a variable that a child function considers \f[I]global\f[R], the value of that \f[I]global\f[R] variable in the child function is the value of the variable in the parent function, not the value of the actual \f[I]global\f[R] variable. .PP All of the above applies to arrays as well. .PP The value of a statement that is an expression (i.e., any of the named expressions or operands) is printed unless the lowest precedence operator is an assignment operator \f[I]and\f[R] the expression is notsurrounded by parentheses. .PP The value that is printed is also assigned to the special variable \f[B]last\f[R]. A single dot (\f[B].\f[R]) may also be used as a synonym for \f[B]last\f[R]. These are \f[B]non-portable extensions\f[R]. .PP Either semicolons or newlines may separate statements. .SS Comments .PP There are two kinds of comments: .IP "1." 3 Block comments are enclosed in \f[B]/*\f[R] and \f[B]*/\f[R]. .IP "2." 3 Line comments go from \f[B]#\f[R] until, and not including, the next newline. This is a \f[B]non-portable extension\f[R]. .SS Named Expressions .PP The following are named expressions in bc(1): .IP "1." 3 Variables: \f[B]I\f[R] .IP "2." 3 Array Elements: \f[B]I[E]\f[R] .IP "3." 3 \f[B]ibase\f[R] .IP "4." 3 \f[B]obase\f[R] .IP "5." 3 \f[B]scale\f[R] .IP "6." 3 \f[B]last\f[R] or a single dot (\f[B].\f[R]) .PP Number 6 is a \f[B]non-portable extension\f[R]. .PP Variables and arrays do not interfere; users can have arrays named the same as variables. This also applies to functions (see the \f[B]FUNCTIONS\f[R] section), so a user can have a variable, array, and function that all have the same name, and they will not shadow each other, whether inside of functions or not. .PP Named expressions are required as the operand of \f[B]increment\f[R]/\f[B]decrement\f[R] operators and as the left side of \f[B]assignment\f[R] operators (see the \f[I]Operators\f[R] subsection). .SS Operands .PP The following are valid operands in bc(1): .IP " 1." 4 Numbers (see the \f[I]Numbers\f[R] subsection below). .IP " 2." 4 Array indices (\f[B]I[E]\f[R]). .IP " 3." 4 \f[B](E)\f[R]: The value of \f[B]E\f[R] (used to change precedence). .IP " 4." 4 \f[B]sqrt(E)\f[R]: The square root of \f[B]E\f[R]. \f[B]E\f[R] must be non-negative. .IP " 5." 4 \f[B]length(E)\f[R]: The number of significant decimal digits in \f[B]E\f[R]. Returns \f[B]1\f[R] for \f[B]0\f[R] with no decimal places. If given a string, the length of the string is returned. Passing a string to \f[B]length(E)\f[R] is a \f[B]non-portable extension\f[R]. .IP " 6." 4 \f[B]length(I[])\f[R]: The number of elements in the array \f[B]I\f[R]. This is a \f[B]non-portable extension\f[R]. .IP " 7." 4 \f[B]scale(E)\f[R]: The \f[I]scale\f[R] of \f[B]E\f[R]. .IP " 8." 4 \f[B]abs(E)\f[R]: The absolute value of \f[B]E\f[R]. This is a \f[B]non-portable extension\f[R]. .IP " 9." 4 \f[B]modexp(E, E, E)\f[R]: Modular exponentiation, where the first expression is the base, the second is the exponent, and the third is the modulus. All three values must be integers. The second argument must be non-negative. The third argument must be non-zero. This is a \f[B]non-portable extension\f[R]. .IP "10." 4 \f[B]divmod(E, E, I[])\f[R]: Division and modulus in one operation. This is for optimization. The first expression is the dividend, and the second is the divisor, which must be non-zero. The return value is the quotient, and the modulus is stored in index \f[B]0\f[R] of the provided array (the last argument). This is a \f[B]non-portable extension\f[R]. .IP "11." 4 \f[B]asciify(E)\f[R]: If \f[B]E\f[R] is a string, returns a string that is the first letter of its argument. If it is a number, calculates the number mod \f[B]256\f[R] and returns that number as a one-character string. This is a \f[B]non-portable extension\f[R]. .IP "12." 4 \f[B]I()\f[R], \f[B]I(E)\f[R], \f[B]I(E, E)\f[R], and so on, where \f[B]I\f[R] is an identifier for a non-\f[B]void\f[R] function (see the \f[I]Void Functions\f[R] subsection of the \f[B]FUNCTIONS\f[R] section). The \f[B]E\f[R] argument(s) may also be arrays of the form \f[B]I[]\f[R], which will automatically be turned into array references (see the \f[I]Array References\f[R] subsection of the \f[B]FUNCTIONS\f[R] section) if the corresponding parameter in the function definition is an array reference. .IP "13." 4 \f[B]read()\f[R]: Reads a line from \f[B]stdin\f[R] and uses that as an expression. The result of that expression is the result of the \f[B]read()\f[R] operand. This is a \f[B]non-portable extension\f[R]. .IP "14." 4 \f[B]maxibase()\f[R]: The max allowable \f[B]ibase\f[R]. This is a \f[B]non-portable extension\f[R]. .IP "15." 4 \f[B]maxobase()\f[R]: The max allowable \f[B]obase\f[R]. This is a \f[B]non-portable extension\f[R]. .IP "16." 4 \f[B]maxscale()\f[R]: The max allowable \f[B]scale\f[R]. This is a \f[B]non-portable extension\f[R]. .IP "17." 4 \f[B]line_length()\f[R]: The line length set with \f[B]BC_LINE_LENGTH\f[R] (see the \f[B]ENVIRONMENT VARIABLES\f[R] section). This is a \f[B]non-portable extension\f[R]. .IP "18." 4 \f[B]global_stacks()\f[R]: \f[B]0\f[R] if global stacks are not enabled with the \f[B]-g\f[R] or \f[B]--global-stacks\f[R] options, non-zero otherwise. See the \f[B]OPTIONS\f[R] section. This is a \f[B]non-portable extension\f[R]. .IP "19." 4 \f[B]leading_zero()\f[R]: \f[B]0\f[R] if leading zeroes are not enabled with the \f[B]-z\f[R] or \f[B]\[en]leading-zeroes\f[R] options, non-zero otherwise. See the \f[B]OPTIONS\f[R] section. This is a \f[B]non-portable extension\f[R]. .SS Numbers .PP Numbers are strings made up of digits, uppercase letters, and at most \f[B]1\f[R] period for a radix. Numbers can have up to \f[B]BC_NUM_MAX\f[R] digits. Uppercase letters are equal to \f[B]9\f[R] + their position in the alphabet (i.e., \f[B]A\f[R] equals \f[B]10\f[R], or \f[B]9+1\f[R]). If a digit or letter makes no sense with the current value of \f[B]ibase\f[R], they are set to the value of the highest valid digit in \f[B]ibase\f[R]. .PP Single-character numbers (i.e., \f[B]A\f[R] alone) take the value that they would have if they were valid digits, regardless of the value of \f[B]ibase\f[R]. This means that \f[B]A\f[R] alone always equals decimal \f[B]10\f[R] and \f[B]Z\f[R] alone always equals decimal \f[B]35\f[R]. .SS Operators .PP The following arithmetic and logical operators can be used. They are listed in order of decreasing precedence. Operators in the same group have the same precedence. .TP \f[B]++\f[R] \f[B]--\f[R] Type: Prefix and Postfix .RS .PP Associativity: None .PP Description: \f[B]increment\f[R], \f[B]decrement\f[R] .RE .TP \f[B]-\f[R] \f[B]!\f[R] Type: Prefix .RS .PP Associativity: None .PP Description: \f[B]negation\f[R], \f[B]boolean not\f[R] .RE .TP \f[B]\[ha]\f[R] Type: Binary .RS .PP Associativity: Right .PP Description: \f[B]power\f[R] .RE .TP \f[B]*\f[R] \f[B]/\f[R] \f[B]%\f[R] Type: Binary .RS .PP Associativity: Left .PP Description: \f[B]multiply\f[R], \f[B]divide\f[R], \f[B]modulus\f[R] .RE .TP \f[B]+\f[R] \f[B]-\f[R] Type: Binary .RS .PP Associativity: Left .PP Description: \f[B]add\f[R], \f[B]subtract\f[R] .RE .TP \f[B]=\f[R] \f[B]+=\f[R] \f[B]-=\f[R] \f[B]*=\f[R] \f[B]/=\f[R] \f[B]%=\f[R] \f[B]\[ha]=\f[R] Type: Binary .RS .PP Associativity: Right .PP Description: \f[B]assignment\f[R] .RE .TP \f[B]==\f[R] \f[B]<=\f[R] \f[B]>=\f[R] \f[B]!=\f[R] \f[B]<\f[R] \f[B]>\f[R] Type: Binary .RS .PP Associativity: Left .PP Description: \f[B]relational\f[R] .RE .TP \f[B]&&\f[R] Type: Binary .RS .PP Associativity: Left .PP Description: \f[B]boolean and\f[R] .RE .TP \f[B]||\f[R] Type: Binary .RS .PP Associativity: Left .PP Description: \f[B]boolean or\f[R] .RE .PP The operators will be described in more detail below. .TP \f[B]++\f[R] \f[B]--\f[R] The prefix and postfix \f[B]increment\f[R] and \f[B]decrement\f[R] operators behave exactly like they would in C. They require a named expression (see the \f[I]Named Expressions\f[R] subsection) as an operand. .RS .PP The prefix versions of these operators are more efficient; use them where possible. .RE .TP \f[B]-\f[R] The \f[B]negation\f[R] operator returns \f[B]0\f[R] if a user attempts to negate any expression with the value \f[B]0\f[R]. Otherwise, a copy of the expression with its sign flipped is returned. .TP \f[B]!\f[R] The \f[B]boolean not\f[R] operator returns \f[B]1\f[R] if the expression is \f[B]0\f[R], or \f[B]0\f[R] otherwise. .RS .PP This is a \f[B]non-portable extension\f[R]. .RE .TP \f[B]\[ha]\f[R] The \f[B]power\f[R] operator (not the \f[B]exclusive or\f[R] operator, as it would be in C) takes two expressions and raises the first to the power of the value of the second. The \f[I]scale\f[R] of the result is equal to \f[B]scale\f[R]. .RS .PP The second expression must be an integer (no \f[I]scale\f[R]), and if it is negative, the first value must be non-zero. .RE .TP \f[B]*\f[R] The \f[B]multiply\f[R] operator takes two expressions, multiplies them, and returns the product. If \f[B]a\f[R] is the \f[I]scale\f[R] of the first expression and \f[B]b\f[R] is the \f[I]scale\f[R] of the second expression, the \f[I]scale\f[R] of the result is equal to \f[B]min(a+b,max(scale,a,b))\f[R] where \f[B]min()\f[R] and \f[B]max()\f[R] return the obvious values. .TP \f[B]/\f[R] The \f[B]divide\f[R] operator takes two expressions, divides them, and returns the quotient. The \f[I]scale\f[R] of the result shall be the value of \f[B]scale\f[R]. .RS .PP The second expression must be non-zero. .RE .TP \f[B]%\f[R] The \f[B]modulus\f[R] operator takes two expressions, \f[B]a\f[R] and \f[B]b\f[R], and evaluates them by 1) Computing \f[B]a/b\f[R] to current \f[B]scale\f[R] and 2) Using the result of step 1 to calculate \f[B]a-(a/b)*b\f[R] to \f[I]scale\f[R] \f[B]max(scale+scale(b),scale(a))\f[R]. .RS .PP The second expression must be non-zero. .RE .TP \f[B]+\f[R] The \f[B]add\f[R] operator takes two expressions, \f[B]a\f[R] and \f[B]b\f[R], and returns the sum, with a \f[I]scale\f[R] equal to the max of the \f[I]scale\f[R]s of \f[B]a\f[R] and \f[B]b\f[R]. .TP \f[B]-\f[R] The \f[B]subtract\f[R] operator takes two expressions, \f[B]a\f[R] and \f[B]b\f[R], and returns the difference, with a \f[I]scale\f[R] equal to the max of the \f[I]scale\f[R]s of \f[B]a\f[R] and \f[B]b\f[R]. .TP \f[B]=\f[R] \f[B]+=\f[R] \f[B]-=\f[R] \f[B]*=\f[R] \f[B]/=\f[R] \f[B]%=\f[R] \f[B]\[ha]=\f[R] The \f[B]assignment\f[R] operators take two expressions, \f[B]a\f[R] and \f[B]b\f[R] where \f[B]a\f[R] is a named expression (see the \f[I]Named Expressions\f[R] subsection). .RS .PP For \f[B]=\f[R], \f[B]b\f[R] is copied and the result is assigned to \f[B]a\f[R]. For all others, \f[B]a\f[R] and \f[B]b\f[R] are applied as operands to the corresponding arithmetic operator and the result is assigned to \f[B]a\f[R]. .RE .TP \f[B]==\f[R] \f[B]<=\f[R] \f[B]>=\f[R] \f[B]!=\f[R] \f[B]<\f[R] \f[B]>\f[R] The \f[B]relational\f[R] operators compare two expressions, \f[B]a\f[R] and \f[B]b\f[R], and if the relation holds, according to C language semantics, the result is \f[B]1\f[R]. Otherwise, it is \f[B]0\f[R]. .RS .PP Note that unlike in C, these operators have a lower precedence than the \f[B]assignment\f[R] operators, which means that \f[B]a=b>c\f[R] is interpreted as \f[B](a=b)>c\f[R]. .PP Also, unlike the standard (https://pubs.opengroup.org/onlinepubs/9699919799/utilities/bc.html) requires, these operators can appear anywhere any other expressions can be used. This allowance is a \f[B]non-portable extension\f[R]. .RE .TP \f[B]&&\f[R] The \f[B]boolean and\f[R] operator takes two expressions and returns \f[B]1\f[R] if both expressions are non-zero, \f[B]0\f[R] otherwise. .RS .PP This is \f[I]not\f[R] a short-circuit operator. .PP This is a \f[B]non-portable extension\f[R]. .RE .TP \f[B]||\f[R] The \f[B]boolean or\f[R] operator takes two expressions and returns \f[B]1\f[R] if one of the expressions is non-zero, \f[B]0\f[R] otherwise. .RS .PP This is \f[I]not\f[R] a short-circuit operator. .PP This is a \f[B]non-portable extension\f[R]. .RE .SS Statements .PP The following items are statements: .IP " 1." 4 \f[B]E\f[R] .IP " 2." 4 \f[B]{\f[R] \f[B]S\f[R] \f[B];\f[R] \&... \f[B];\f[R] \f[B]S\f[R] \f[B]}\f[R] .IP " 3." 4 \f[B]if\f[R] \f[B](\f[R] \f[B]E\f[R] \f[B])\f[R] \f[B]S\f[R] .IP " 4." 4 \f[B]if\f[R] \f[B](\f[R] \f[B]E\f[R] \f[B])\f[R] \f[B]S\f[R] \f[B]else\f[R] \f[B]S\f[R] .IP " 5." 4 \f[B]while\f[R] \f[B](\f[R] \f[B]E\f[R] \f[B])\f[R] \f[B]S\f[R] .IP " 6." 4 \f[B]for\f[R] \f[B](\f[R] \f[B]E\f[R] \f[B];\f[R] \f[B]E\f[R] \f[B];\f[R] \f[B]E\f[R] \f[B])\f[R] \f[B]S\f[R] .IP " 7." 4 An empty statement .IP " 8." 4 \f[B]break\f[R] .IP " 9." 4 \f[B]continue\f[R] .IP "10." 4 \f[B]quit\f[R] .IP "11." 4 \f[B]halt\f[R] .IP "12." 4 \f[B]limits\f[R] .IP "13." 4 A string of characters, enclosed in double quotes .IP "14." 4 \f[B]print\f[R] \f[B]E\f[R] \f[B],\f[R] \&... \f[B],\f[R] \f[B]E\f[R] .IP "15." 4 \f[B]stream\f[R] \f[B]E\f[R] \f[B],\f[R] \&... \f[B],\f[R] \f[B]E\f[R] .IP "16." 4 \f[B]I()\f[R], \f[B]I(E)\f[R], \f[B]I(E, E)\f[R], and so on, where \f[B]I\f[R] is an identifier for a \f[B]void\f[R] function (see the \f[I]Void Functions\f[R] subsection of the \f[B]FUNCTIONS\f[R] section). The \f[B]E\f[R] argument(s) may also be arrays of the form \f[B]I[]\f[R], which will automatically be turned into array references (see the \f[I]Array References\f[R] subsection of the \f[B]FUNCTIONS\f[R] section) if the corresponding parameter in the function definition is an array reference. .PP Numbers 4, 9, 11, 12, 14, 15, and 16 are \f[B]non-portable extensions\f[R]. .PP Also, as a \f[B]non-portable extension\f[R], any or all of the expressions in the header of a for loop may be omitted. If the condition (second expression) is omitted, it is assumed to be a constant \f[B]1\f[R]. .PP The \f[B]break\f[R] statement causes a loop to stop iterating and resume execution immediately following a loop. This is only allowed in loops. .PP The \f[B]continue\f[R] statement causes a loop iteration to stop early and returns to the start of the loop, including testing the loop condition. This is only allowed in loops. .PP The \f[B]if\f[R] \f[B]else\f[R] statement does the same thing as in C. .PP The \f[B]quit\f[R] statement causes bc(1) to quit, even if it is on a branch that will not be executed (it is a compile-time command). .PP The \f[B]halt\f[R] statement causes bc(1) to quit, if it is executed. (Unlike \f[B]quit\f[R] if it is on a branch of an \f[B]if\f[R] statement that is not executed, bc(1) does not quit.) .PP The \f[B]limits\f[R] statement prints the limits that this bc(1) is subject to. This is like the \f[B]quit\f[R] statement in that it is a compile-time command. .PP An expression by itself is evaluated and printed, followed by a newline. .SS Strings .PP If strings appear as a statement by themselves, they are printed without a trailing newline. .PP In addition to appearing as a lone statement by themselves, strings can be assigned to variables and array elements. They can also be passed to functions in variable parameters. .PP If any statement that expects a string is given a variable that had a string assigned to it, the statement acts as though it had received a string. .PP If any math operation is attempted on a string or a variable or array element that has been assigned a string, an error is raised, and bc(1) resets (see the \f[B]RESET\f[R] section). .PP Assigning strings to variables and array elements and passing them to functions are \f[B]non-portable extensions\f[R]. .SS Print Statement .PP The \[lq]expressions\[rq] in a \f[B]print\f[R] statement may also be strings. If they are, there are backslash escape sequences that are interpreted specially. What those sequences are, and what they cause to be printed, are shown below: .PP \f[B]\[rs]a\f[R]: \f[B]\[rs]a\f[R] .PP \f[B]\[rs]b\f[R]: \f[B]\[rs]b\f[R] .PP \f[B]\[rs]\[rs]\f[R]: \f[B]\[rs]\f[R] .PP \f[B]\[rs]e\f[R]: \f[B]\[rs]\f[R] .PP \f[B]\[rs]f\f[R]: \f[B]\[rs]f\f[R] .PP \f[B]\[rs]n\f[R]: \f[B]\[rs]n\f[R] .PP \f[B]\[rs]q\f[R]: \f[B]\[lq]\f[R] .PP \f[B]\[rs]r\f[R]: \f[B]\[rs]r\f[R] .PP \f[B]\[rs]t\f[R]: \f[B]\[rs]t\f[R] .PP Any other character following a backslash causes the backslash and character to be printed as-is. .PP Any non-string expression in a print statement shall be assigned to \f[B]last\f[R], like any other expression that is printed. .SS Stream Statement .PP The \[lq]expressions in a \f[B]stream\f[R] statement may also be strings. .PP If a \f[B]stream\f[R] statement is given a string, it prints the string as though the string had appeared as its own statement. In other words, the \f[B]stream\f[R] statement prints strings normally, without a newline. .PP If a \f[B]stream\f[R] statement is given a number, a copy of it is truncated and its absolute value is calculated. The result is then printed as though \f[B]obase\f[R] is \f[B]256\f[R] and each digit is interpreted as an 8-bit ASCII character, making it a byte stream. .SS Order of Evaluation .PP All expressions in a statment are evaluated left to right, except as necessary to maintain order of operations. This means, for example, assuming that \f[B]i\f[R] is equal to \f[B]0\f[R], in the expression .IP .nf \f[C] a[i++] = i++ \f[R] .fi .PP the first (or 0th) element of \f[B]a\f[R] is set to \f[B]1\f[R], and \f[B]i\f[R] is equal to \f[B]2\f[R] at the end of the expression. .PP This includes function arguments. Thus, assuming \f[B]i\f[R] is equal to \f[B]0\f[R], this means that in the expression .IP .nf \f[C] x(i++, i++) \f[R] .fi .PP the first argument passed to \f[B]x()\f[R] is \f[B]0\f[R], and the second argument is \f[B]1\f[R], while \f[B]i\f[R] is equal to \f[B]2\f[R] before the function starts executing. .SH FUNCTIONS .PP Function definitions are as follows: .IP .nf \f[C] define I(I,...,I){ auto I,...,I S;...;S return(E) } \f[R] .fi .PP Any \f[B]I\f[R] in the parameter list or \f[B]auto\f[R] list may be replaced with \f[B]I[]\f[R] to make a parameter or \f[B]auto\f[R] var an array, and any \f[B]I\f[R] in the parameter list may be replaced with \f[B]*I[]\f[R] to make a parameter an array reference. Callers of functions that take array references should not put an asterisk in the call; they must be called with just \f[B]I[]\f[R] like normal array parameters and will be automatically converted into references. .PP As a \f[B]non-portable extension\f[R], the opening brace of a \f[B]define\f[R] statement may appear on the next line. .PP As a \f[B]non-portable extension\f[R], the return statement may also be in one of the following forms: .IP "1." 3 \f[B]return\f[R] .IP "2." 3 \f[B]return\f[R] \f[B](\f[R] \f[B])\f[R] .IP "3." 3 \f[B]return\f[R] \f[B]E\f[R] .PP The first two, or not specifying a \f[B]return\f[R] statement, is equivalent to \f[B]return (0)\f[R], unless the function is a \f[B]void\f[R] function (see the \f[I]Void Functions\f[R] subsection below). .SS Void Functions .PP Functions can also be \f[B]void\f[R] functions, defined as follows: .IP .nf \f[C] define void I(I,...,I){ auto I,...,I S;...;S return } \f[R] .fi .PP They can only be used as standalone expressions, where such an expression would be printed alone, except in a print statement. .PP Void functions can only use the first two \f[B]return\f[R] statements listed above. They can also omit the return statement entirely. .PP The word \[lq]void\[rq] is not treated as a keyword; it is still possible to have variables, arrays, and functions named \f[B]void\f[R]. The word \[lq]void\[rq] is only treated specially right after the \f[B]define\f[R] keyword. .PP This is a \f[B]non-portable extension\f[R]. .SS Array References .PP For any array in the parameter list, if the array is declared in the form .IP .nf \f[C] *I[] \f[R] .fi .PP it is a \f[B]reference\f[R]. Any changes to the array in the function are reflected, when the function returns, to the array that was passed in. .PP Other than this, all function arguments are passed by value. .PP This is a \f[B]non-portable extension\f[R]. .SH LIBRARY .PP All of the functions below are available when the \f[B]-l\f[R] or \f[B]--mathlib\f[R] command-line flags are given. .SS Standard Library .PP The standard (https://pubs.opengroup.org/onlinepubs/9699919799/utilities/bc.html) defines the following functions for the math library: .TP \f[B]s(x)\f[R] Returns the sine of \f[B]x\f[R], which is assumed to be in radians. .RS .PP This is a transcendental function (see the \f[I]Transcendental Functions\f[R] subsection below). .RE .TP \f[B]c(x)\f[R] Returns the cosine of \f[B]x\f[R], which is assumed to be in radians. .RS .PP This is a transcendental function (see the \f[I]Transcendental Functions\f[R] subsection below). .RE .TP \f[B]a(x)\f[R] Returns the arctangent of \f[B]x\f[R], in radians. .RS .PP This is a transcendental function (see the \f[I]Transcendental Functions\f[R] subsection below). .RE .TP \f[B]l(x)\f[R] Returns the natural logarithm of \f[B]x\f[R]. .RS .PP This is a transcendental function (see the \f[I]Transcendental Functions\f[R] subsection below). .RE .TP \f[B]e(x)\f[R] Returns the mathematical constant \f[B]e\f[R] raised to the power of \f[B]x\f[R]. .RS .PP This is a transcendental function (see the \f[I]Transcendental Functions\f[R] subsection below). .RE .TP \f[B]j(x, n)\f[R] Returns the bessel integer order \f[B]n\f[R] (truncated) of \f[B]x\f[R]. .RS .PP This is a transcendental function (see the \f[I]Transcendental Functions\f[R] subsection below). .RE .SS Transcendental Functions .PP All transcendental functions can return slightly inaccurate results (up to 1 ULP (https://en.wikipedia.org/wiki/Unit_in_the_last_place)). This is unavoidable, and this article (https://people.eecs.berkeley.edu/~wkahan/LOG10HAF.TXT) explains why it is impossible and unnecessary to calculate exact results for the transcendental functions. .PP Because of the possible inaccuracy, I recommend that users call those functions with the precision (\f[B]scale\f[R]) set to at least 1 higher than is necessary. If exact results are \f[I]absolutely\f[R] required, users can double the precision (\f[B]scale\f[R]) and then truncate. .PP The transcendental functions in the standard math library are: .IP \[bu] 2 \f[B]s(x)\f[R] .IP \[bu] 2 \f[B]c(x)\f[R] .IP \[bu] 2 \f[B]a(x)\f[R] .IP \[bu] 2 \f[B]l(x)\f[R] .IP \[bu] 2 \f[B]e(x)\f[R] .IP \[bu] 2 \f[B]j(x, n)\f[R] .SH RESET .PP When bc(1) encounters an error or a signal that it has a non-default handler for, it resets. This means that several things happen. .PP First, any functions that are executing are stopped and popped off the stack. The behavior is not unlike that of exceptions in programming languages. Then the execution point is set so that any code waiting to execute (after all functions returned) is skipped. .PP Thus, when bc(1) resets, it skips any remaining code waiting to be executed. Then, if it is interactive mode, and the error was not a fatal error (see the \f[B]EXIT STATUS\f[R] section), it asks for more input; otherwise, it exits with the appropriate return code. .PP Note that this reset behavior is different from the GNU bc(1), which attempts to start executing the statement right after the one that caused an error. .SH PERFORMANCE .PP Most bc(1) implementations use \f[B]char\f[R] types to calculate the value of \f[B]1\f[R] decimal digit at a time, but that can be slow. This bc(1) does something different. .PP It uses large integers to calculate more than \f[B]1\f[R] decimal digit at a time. If built in a environment where \f[B]BC_LONG_BIT\f[R] (see the \f[B]LIMITS\f[R] section) is \f[B]64\f[R], then each integer has \f[B]9\f[R] decimal digits. If built in an environment where \f[B]BC_LONG_BIT\f[R] is \f[B]32\f[R] then each integer has \f[B]4\f[R] decimal digits. This value (the number of decimal digits per large integer) is called \f[B]BC_BASE_DIGS\f[R]. .PP The actual values of \f[B]BC_LONG_BIT\f[R] and \f[B]BC_BASE_DIGS\f[R] can be queried with the \f[B]limits\f[R] statement. .PP In addition, this bc(1) uses an even larger integer for overflow checking. This integer type depends on the value of \f[B]BC_LONG_BIT\f[R], but is always at least twice as large as the integer type used to store digits. .SH LIMITS .PP The following are the limits on bc(1): .TP \f[B]BC_LONG_BIT\f[R] The number of bits in the \f[B]long\f[R] type in the environment where bc(1) was built. This determines how many decimal digits can be stored in a single large integer (see the \f[B]PERFORMANCE\f[R] section). .TP \f[B]BC_BASE_DIGS\f[R] The number of decimal digits per large integer (see the \f[B]PERFORMANCE\f[R] section). Depends on \f[B]BC_LONG_BIT\f[R]. .TP \f[B]BC_BASE_POW\f[R] The max decimal number that each large integer can store (see \f[B]BC_BASE_DIGS\f[R]) plus \f[B]1\f[R]. Depends on \f[B]BC_BASE_DIGS\f[R]. .TP \f[B]BC_OVERFLOW_MAX\f[R] The max number that the overflow type (see the \f[B]PERFORMANCE\f[R] section) can hold. Depends on \f[B]BC_LONG_BIT\f[R]. .TP \f[B]BC_BASE_MAX\f[R] The maximum output base. Set at \f[B]BC_BASE_POW\f[R]. .TP \f[B]BC_DIM_MAX\f[R] The maximum size of arrays. Set at \f[B]SIZE_MAX-1\f[R]. .TP \f[B]BC_SCALE_MAX\f[R] The maximum \f[B]scale\f[R]. Set at \f[B]BC_OVERFLOW_MAX-1\f[R]. .TP \f[B]BC_STRING_MAX\f[R] The maximum length of strings. Set at \f[B]BC_OVERFLOW_MAX-1\f[R]. .TP \f[B]BC_NAME_MAX\f[R] The maximum length of identifiers. Set at \f[B]BC_OVERFLOW_MAX-1\f[R]. .TP \f[B]BC_NUM_MAX\f[R] The maximum length of a number (in decimal digits), which includes digits after the decimal point. Set at \f[B]BC_OVERFLOW_MAX-1\f[R]. .TP Exponent The maximum allowable exponent (positive or negative). Set at \f[B]BC_OVERFLOW_MAX\f[R]. .TP Number of vars The maximum number of vars/arrays. Set at \f[B]SIZE_MAX-1\f[R]. .PP The actual values can be queried with the \f[B]limits\f[R] statement. .PP These limits are meant to be effectively non-existent; the limits are so large (at least on 64-bit machines) that there should not be any point at which they become a problem. In fact, memory should be exhausted before these limits should be hit. .SH ENVIRONMENT VARIABLES .PP bc(1) recognizes the following environment variables: .TP \f[B]POSIXLY_CORRECT\f[R] If this variable exists (no matter the contents), bc(1) behaves as if the \f[B]-s\f[R] option was given. .TP \f[B]BC_ENV_ARGS\f[R] This is another way to give command-line arguments to bc(1). They should be in the same format as all other command-line arguments. These are always processed first, so any files given in \f[B]BC_ENV_ARGS\f[R] will be processed before arguments and files given on the command-line. This gives the user the ability to set up \[lq]standard\[rq] options and files to be used at every invocation. The most useful thing for such files to contain would be useful functions that the user might want every time bc(1) runs. .RS .PP The code that parses \f[B]BC_ENV_ARGS\f[R] will correctly handle quoted arguments, but it does not understand escape sequences. For example, the string \f[B]\[lq]/home/gavin/some bc file.bc\[rq]\f[R] will be correctly parsed, but the string \f[B]\[lq]/home/gavin/some \[dq]bc\[dq] file.bc\[rq]\f[R] will include the backslashes. .PP The quote parsing will handle either kind of quotes, \f[B]\[cq]\f[R] or \f[B]\[lq]\f[R]. Thus, if you have a file with any number of single quotes in the name, you can use double quotes as the outside quotes, as in \f[B]\[lq]some `bc' file.bc\[rq]\f[R], and vice versa if you have a file with double quotes. However, handling a file with both kinds of quotes in \f[B]BC_ENV_ARGS\f[R] is not supported due to the complexity of the parsing, though such files are still supported on the command-line where the parsing is done by the shell. .RE .TP \f[B]BC_LINE_LENGTH\f[R] If this environment variable exists and contains an integer that is greater than \f[B]1\f[R] and is less than \f[B]UINT16_MAX\f[R] (\f[B]2\[ha]16-1\f[R]), bc(1) will output lines to that length, including the backslash (\f[B]\[rs]\f[R]). The default line length is \f[B]70\f[R]. .RS .PP The special value of \f[B]0\f[R] will disable line length checking and print numbers without regard to line length and without backslashes and newlines. .RE .TP \f[B]BC_BANNER\f[R] If this environment variable exists and contains an integer, then a non-zero value activates the copyright banner when bc(1) is in interactive mode, while zero deactivates it. .RS .PP If bc(1) is not in interactive mode (see the \f[B]INTERACTIVE MODE\f[R] section), then this environment variable has no effect because bc(1) does not print the banner when not in interactive mode. .PP This environment variable overrides the default, which can be queried with the \f[B]-h\f[R] or \f[B]--help\f[R] options. .RE .TP \f[B]BC_SIGINT_RESET\f[R] If bc(1) is not in interactive mode (see the \f[B]INTERACTIVE MODE\f[R] section), then this environment variable has no effect because bc(1) exits on \f[B]SIGINT\f[R] when not in interactive mode. .RS .PP However, when bc(1) is in interactive mode, then if this environment variable exists and contains an integer, a non-zero value makes bc(1) reset on \f[B]SIGINT\f[R], rather than exit, and zero makes bc(1) exit. If this environment variable exists and is \f[I]not\f[R] an integer, then bc(1) will exit on \f[B]SIGINT\f[R]. .PP This environment variable overrides the default, which can be queried with the \f[B]-h\f[R] or \f[B]--help\f[R] options. .RE .TP \f[B]BC_TTY_MODE\f[R] If TTY mode is \f[I]not\f[R] available (see the \f[B]TTY MODE\f[R] section), then this environment variable has no effect. .RS .PP However, when TTY mode is available, then if this environment variable exists and contains an integer, then a non-zero value makes bc(1) use TTY mode, and zero makes bc(1) not use TTY mode. .PP This environment variable overrides the default, which can be queried with the \f[B]-h\f[R] or \f[B]--help\f[R] options. .RE .TP \f[B]BC_PROMPT\f[R] If TTY mode is \f[I]not\f[R] available (see the \f[B]TTY MODE\f[R] section), then this environment variable has no effect. .RS .PP However, when TTY mode is available, then if this environment variable exists and contains an integer, a non-zero value makes bc(1) use a prompt, and zero or a non-integer makes bc(1) not use a prompt. If this environment variable does not exist and \f[B]BC_TTY_MODE\f[R] does, then the value of the \f[B]BC_TTY_MODE\f[R] environment variable is used. .PP This environment variable and the \f[B]BC_TTY_MODE\f[R] environment variable override the default, which can be queried with the \f[B]-h\f[R] or \f[B]--help\f[R] options. .RE +.TP +\f[B]BC_EXPR_EXIT\f[R] +If any expressions or expression files are given on the command-line +with \f[B]-e\f[R], \f[B]--expression\f[R], \f[B]-f\f[R], or +\f[B]--file\f[R], then if this environment variable exists and contains +an integer, a non-zero value makes bc(1) exit after executing the +expressions and expression files, and a non-zero value makes bc(1) not +exit. +.RS +.PP +This environment variable overrides the default, which can be queried +with the \f[B]-h\f[R] or \f[B]--help\f[R] options. +.RE .SH EXIT STATUS .PP bc(1) returns the following exit statuses: .TP \f[B]0\f[R] No error. .TP \f[B]1\f[R] A math error occurred. This follows standard practice of using \f[B]1\f[R] for expected errors, since math errors will happen in the process of normal execution. .RS .PP Math errors include divide by \f[B]0\f[R], taking the square root of a negative number, attempting to convert a negative number to a hardware integer, overflow when converting a number to a hardware integer, overflow when calculating the size of a number, and attempting to use a non-integer where an integer is required. .PP Converting to a hardware integer happens for the second operand of the power (\f[B]\[ha]\f[R]) operator and the corresponding assignment operator. .RE .TP \f[B]2\f[R] A parse error occurred. .RS .PP Parse errors include unexpected \f[B]EOF\f[R], using an invalid character, failing to find the end of a string or comment, using a token where it is invalid, giving an invalid expression, giving an invalid print statement, giving an invalid function definition, attempting to assign to an expression that is not a named expression (see the \f[I]Named Expressions\f[R] subsection of the \f[B]SYNTAX\f[R] section), giving an invalid \f[B]auto\f[R] list, having a duplicate \f[B]auto\f[R]/function parameter, failing to find the end of a code block, attempting to return a value from a \f[B]void\f[R] function, attempting to use a variable as a reference, and using any extensions when the option \f[B]-s\f[R] or any equivalents were given. .RE .TP \f[B]3\f[R] A runtime error occurred. .RS .PP Runtime errors include assigning an invalid number to any global (\f[B]ibase\f[R], \f[B]obase\f[R], or \f[B]scale\f[R]), giving a bad expression to a \f[B]read()\f[R] call, calling \f[B]read()\f[R] inside of a \f[B]read()\f[R] call, type errors, passing the wrong number of arguments to functions, attempting to call an undefined function, and attempting to use a \f[B]void\f[R] function call as a value in an expression. .RE .TP \f[B]4\f[R] A fatal error occurred. .RS .PP Fatal errors include memory allocation errors, I/O errors, failing to open files, attempting to use files that do not have only ASCII characters (bc(1) only accepts ASCII characters), attempting to open a directory as a file, and giving invalid command-line options. .RE .PP The exit status \f[B]4\f[R] is special; when a fatal error occurs, bc(1) always exits and returns \f[B]4\f[R], no matter what mode bc(1) is in. .PP The other statuses will only be returned when bc(1) is not in interactive mode (see the \f[B]INTERACTIVE MODE\f[R] section), since bc(1) resets its state (see the \f[B]RESET\f[R] section) and accepts more input when one of those errors occurs in interactive mode. This is also the case when interactive mode is forced by the \f[B]-i\f[R] flag or \f[B]--interactive\f[R] option. .PP These exit statuses allow bc(1) to be used in shell scripting with error checking, and its normal behavior can be forced by using the \f[B]-i\f[R] flag or \f[B]--interactive\f[R] option. .SH INTERACTIVE MODE .PP Per the standard (https://pubs.opengroup.org/onlinepubs/9699919799/utilities/bc.html), bc(1) has an interactive mode and a non-interactive mode. Interactive mode is turned on automatically when both \f[B]stdin\f[R] and \f[B]stdout\f[R] are hooked to a terminal, but the \f[B]-i\f[R] flag and \f[B]--interactive\f[R] option can turn it on in other situations. .PP In interactive mode, bc(1) attempts to recover from errors (see the \f[B]RESET\f[R] section), and in normal execution, flushes \f[B]stdout\f[R] as soon as execution is done for the current input. bc(1) may also reset on \f[B]SIGINT\f[R] instead of exit, depending on the contents of, or default for, the \f[B]BC_SIGINT_RESET\f[R] environment variable (see the \f[B]ENVIRONMENT VARIABLES\f[R] section). .SH TTY MODE .PP If \f[B]stdin\f[R], \f[B]stdout\f[R], and \f[B]stderr\f[R] are all connected to a TTY, then \[lq]TTY mode\[rq] is considered to be available, and thus, bc(1) can turn on TTY mode, subject to some settings. .PP If there is the environment variable \f[B]BC_TTY_MODE\f[R] in the environment (see the \f[B]ENVIRONMENT VARIABLES\f[R] section), then if that environment variable contains a non-zero integer, bc(1) will turn on TTY mode when \f[B]stdin\f[R], \f[B]stdout\f[R], and \f[B]stderr\f[R] are all connected to a TTY. If the \f[B]BC_TTY_MODE\f[R] environment variable exists but is \f[I]not\f[R] a non-zero integer, then bc(1) will not turn TTY mode on. .PP If the environment variable \f[B]BC_TTY_MODE\f[R] does \f[I]not\f[R] exist, the default setting is used. The default setting can be queried with the \f[B]-h\f[R] or \f[B]--help\f[R] options. .PP TTY mode is different from interactive mode because interactive mode is required in the bc(1) specification (https://pubs.opengroup.org/onlinepubs/9699919799/utilities/bc.html), and interactive mode requires only \f[B]stdin\f[R] and \f[B]stdout\f[R] to be connected to a terminal. .SS Command-Line History .PP Command-line history is only enabled if TTY mode is, i.e., that \f[B]stdin\f[R], \f[B]stdout\f[R], and \f[B]stderr\f[R] are connected to a TTY and the \f[B]BC_TTY_MODE\f[R] environment variable (see the \f[B]ENVIRONMENT VARIABLES\f[R] section) and its default do not disable TTY mode. See the \f[B]COMMAND LINE HISTORY\f[R] section for more information. .SS Prompt .PP If TTY mode is available, then a prompt can be enabled. Like TTY mode itself, it can be turned on or off with an environment variable: \f[B]BC_PROMPT\f[R] (see the \f[B]ENVIRONMENT VARIABLES\f[R] section). .PP If the environment variable \f[B]BC_PROMPT\f[R] exists and is a non-zero integer, then the prompt is turned on when \f[B]stdin\f[R], \f[B]stdout\f[R], and \f[B]stderr\f[R] are connected to a TTY and the \f[B]-P\f[R] and \f[B]--no-prompt\f[R] options were not used. The read prompt will be turned on under the same conditions, except that the \f[B]-R\f[R] and \f[B]--no-read-prompt\f[R] options must also not be used. .PP However, if \f[B]BC_PROMPT\f[R] does not exist, the prompt can be enabled or disabled with the \f[B]BC_TTY_MODE\f[R] environment variable, the \f[B]-P\f[R] and \f[B]--no-prompt\f[R] options, and the \f[B]-R\f[R] and \f[B]--no-read-prompt\f[R] options. See the \f[B]ENVIRONMENT VARIABLES\f[R] and \f[B]OPTIONS\f[R] sections for more details. .SH SIGNAL HANDLING .PP Sending a \f[B]SIGINT\f[R] will cause bc(1) to do one of two things. .PP If bc(1) is not in interactive mode (see the \f[B]INTERACTIVE MODE\f[R] section), or the \f[B]BC_SIGINT_RESET\f[R] environment variable (see the \f[B]ENVIRONMENT VARIABLES\f[R] section), or its default, is either not an integer or it is zero, bc(1) will exit. .PP However, if bc(1) is in interactive mode, and the \f[B]BC_SIGINT_RESET\f[R] or its default is an integer and non-zero, then bc(1) will stop executing the current input and reset (see the \f[B]RESET\f[R] section) upon receiving a \f[B]SIGINT\f[R]. .PP Note that \[lq]current input\[rq] can mean one of two things. If bc(1) is processing input from \f[B]stdin\f[R] in interactive mode, it will ask for more input. If bc(1) is processing input from a file in interactive mode, it will stop processing the file and start processing the next file, if one exists, or ask for input from \f[B]stdin\f[R] if no other file exists. .PP This means that if a \f[B]SIGINT\f[R] is sent to bc(1) as it is executing a file, it can seem as though bc(1) did not respond to the signal since it will immediately start executing the next file. This is by design; most files that users execute when interacting with bc(1) have function definitions, which are quick to parse. If a file takes a long time to execute, there may be a bug in that file. The rest of the files could still be executed without problem, allowing the user to continue. .PP \f[B]SIGTERM\f[R] and \f[B]SIGQUIT\f[R] cause bc(1) to clean up and exit, and it uses the default handler for all other signals. The one exception is \f[B]SIGHUP\f[R]; in that case, and only when bc(1) is in TTY mode (see the \f[B]TTY MODE\f[R] section), a \f[B]SIGHUP\f[R] will cause bc(1) to clean up and exit. .SH COMMAND LINE HISTORY .PP bc(1) supports interactive command-line editing. .PP If bc(1) can be in TTY mode (see the \f[B]TTY MODE\f[R] section), history can be enabled. This means that command-line history can only be enabled when \f[B]stdin\f[R], \f[B]stdout\f[R], and \f[B]stderr\f[R] are all connected to a TTY. .PP Like TTY mode itself, it can be turned on or off with the environment variable \f[B]BC_TTY_MODE\f[R] (see the \f[B]ENVIRONMENT VARIABLES\f[R] section). .PP If history is enabled, previous lines can be recalled and edited with the arrow keys. .PP \f[B]Note\f[R]: tabs are converted to 8 spaces. .SH SEE ALSO .PP dc(1) .SH STANDARDS .PP bc(1) is compliant with the IEEE Std 1003.1-2017 (\[lq]POSIX.1-2017\[rq]) (https://pubs.opengroup.org/onlinepubs/9699919799/utilities/bc.html) specification. The flags \f[B]-efghiqsvVw\f[R], all long options, and the extensions noted above are extensions to that specification. .PP Note that the specification explicitly says that bc(1) only accepts numbers that use a period (\f[B].\f[R]) as a radix point, regardless of the value of \f[B]LC_NUMERIC\f[R]. .SH BUGS .PP None are known. Report bugs at https://git.yzena.com/gavin/bc. .SH AUTHORS .PP Gavin D. Howard and contributors. diff --git a/contrib/bc/manuals/bc/EN.1.md b/contrib/bc/manuals/bc/EN.1.md index e77d64cd7a56..13ad5f8b570a 100644 --- a/contrib/bc/manuals/bc/EN.1.md +++ b/contrib/bc/manuals/bc/EN.1.md @@ -1,1357 +1,1368 @@ # NAME bc - arbitrary-precision decimal arithmetic language and calculator # SYNOPSIS **bc** [**-ghilPqRsvVw**] [**-\-global-stacks**] [**-\-help**] [**-\-interactive**] [**-\-mathlib**] [**-\-no-prompt**] [**-\-no-read-prompt**] [**-\-quiet**] [**-\-standard**] [**-\-warn**] [**-\-version**] [**-e** *expr*] [**-\-expression**=*expr*...] [**-f** *file*...] [**-\-file**=*file*...] [*file*...] # DESCRIPTION bc(1) is an interactive processor for a language first standardized in 1991 by POSIX. (The current standard is [here][1].) The language provides unlimited precision decimal arithmetic and is somewhat C-like, but there are differences. Such differences will be noted in this document. After parsing and handling options, this bc(1) reads any files given on the command line and executes them before reading from **stdin**. This bc(1) is a drop-in replacement for *any* bc(1), including (and especially) the GNU bc(1). **Note**: If running this bc(1) on *any* script meant for another bc(1) gives a parse error, it is probably because a word this bc(1) reserves as a keyword is used as the name of a function, variable, or array. To fix that, use the command-line option **-r** *keyword*, where *keyword* is the keyword that is used as a name in the script. For more information, see the **OPTIONS** section. If parsing scripts meant for other bc(1) implementations still does not work, that is a bug and should be reported. See the **BUGS** section. # OPTIONS The following are the options that bc(1) accepts. **-g**, **-\-global-stacks** : Turns the globals **ibase**, **obase**, and **scale** into stacks. This has the effect that a copy of the current value of all three are pushed onto a stack for every function call, as well as popped when every function returns. This means that functions can assign to any and all of those globals without worrying that the change will affect other functions. Thus, a hypothetical function named **output(x,b)** that simply printed **x** in base **b** could be written like this: define void output(x, b) { obase=b x } instead of like this: define void output(x, b) { auto c c=obase obase=b x obase=c } This makes writing functions much easier. However, since using this flag means that functions cannot set **ibase**, **obase**, or **scale** globally, functions that are made to do so cannot work anymore. There are two possible use cases for that, and each has a solution. First, if a function is called on startup to turn bc(1) into a number converter, it is possible to replace that capability with various shell aliases. Examples: alias d2o="bc -e ibase=A -e obase=8" alias h2b="bc -e ibase=G -e obase=2" Second, if the purpose of a function is to set **ibase**, **obase**, or **scale** globally for any other purpose, it could be split into one to three functions (based on how many globals it sets) and each of those functions could return the desired value for a global. If the behavior of this option is desired for every run of bc(1), then users could make sure to define **BC_ENV_ARGS** and include this option (see the **ENVIRONMENT VARIABLES** section for more details). If **-s**, **-w**, or any equivalents are used, this option is ignored. This is a **non-portable extension**. **-h**, **-\-help** : Prints a usage message and quits. **-i**, **-\-interactive** : Forces interactive mode. (See the **INTERACTIVE MODE** section.) This is a **non-portable extension**. **-L**, **-\-no-line-length** : Disables line length checking and prints numbers without backslashes and newlines. In other words, this option sets **BC_LINE_LENGTH** to **0** (see the **ENVIRONMENT VARIABLES** section). This is a **non-portable extension**. **-l**, **-\-mathlib** : Sets **scale** (see the **SYNTAX** section) to **20** and loads the included math library before running any code, including any expressions or files specified on the command line. To learn what is in the library, see the **LIBRARY** section. **-P**, **-\-no-prompt** : Disables the prompt in TTY mode. (The prompt is only enabled in TTY mode. See the **TTY MODE** section.) This is mostly for those users that do not want a prompt or are not used to having them in bc(1). Most of those users would want to put this option in **BC_ENV_ARGS** (see the **ENVIRONMENT VARIABLES** section). These options override the **BC_PROMPT** and **BC_TTY_MODE** environment variables (see the **ENVIRONMENT VARIABLES** section). This is a **non-portable extension**. **-R**, **-\-no-read-prompt** : Disables the read prompt in TTY mode. (The read prompt is only enabled in TTY mode. See the **TTY MODE** section.) This is mostly for those users that do not want a read prompt or are not used to having them in bc(1). Most of those users would want to put this option in **BC_ENV_ARGS** (see the **ENVIRONMENT VARIABLES** section). This option is also useful in hash bang lines of bc(1) scripts that prompt for user input. This option does not disable the regular prompt because the read prompt is only used when the **read()** built-in function is called. These options *do* override the **BC_PROMPT** and **BC_TTY_MODE** environment variables (see the **ENVIRONMENT VARIABLES** section), but only for the read prompt. This is a **non-portable extension**. **-r** *keyword*, **-\-redefine**=*keyword* : Redefines *keyword* in order to allow it to be used as a function, variable, or array name. This is useful when this bc(1) gives parse errors when parsing scripts meant for other bc(1) implementations. The keywords this bc(1) allows to be redefined are: * **abs** * **asciify** * **continue** * **divmod** * **else** * **halt** * **last** * **limits** * **maxibase** * **maxobase** * **maxscale** * **modexp** * **print** * **read** * **stream** If any of those keywords are used as a function, variable, or array name in a script, use this option with the keyword as the argument. If multiple are used, use this option for all of them; it can be used multiple times. Keywords are *not* redefined when parsing the builtin math library (see the **LIBRARY** section). It is a fatal error to redefine keywords mandated by the POSIX standard. It is a fatal error to attempt to redefine words that this bc(1) does not reserve as keywords. **-q**, **-\-quiet** : This option is for compatibility with the [GNU bc(1)][2]; it is a no-op. Without this option, GNU bc(1) prints a copyright header. This bc(1) only prints the copyright header if one or more of the **-v**, **-V**, or **-\-version** options are given. This is a **non-portable extension**. **-s**, **-\-standard** : Process exactly the language defined by the [standard][1] and error if any extensions are used. This is a **non-portable extension**. **-v**, **-V**, **-\-version** : Print the version information (copyright header) and exit. This is a **non-portable extension**. **-w**, **-\-warn** : Like **-s** and **-\-standard**, except that warnings (and not errors) are printed for non-standard extensions and execution continues normally. This is a **non-portable extension**. **-z**, **-\-leading-zeroes** : Makes bc(1) print all numbers greater than **-1** and less than **1**, and not equal to **0**, with a leading zero. This can be set for individual numbers with the **plz(x)**, plznl(x)**, **pnlz(x)**, and **pnlznl(x)** functions in the extended math library (see the **LIBRARY** section). This is a **non-portable extension**. **-e** *expr*, **-\-expression**=*expr* : Evaluates *expr*. If multiple expressions are given, they are evaluated in order. If files are given as well (see below), the expressions and files are evaluated in the order given. This means that if a file is given before an expression, the file is read in and evaluated first. If this option is given on the command-line (i.e., not in **BC_ENV_ARGS**, see the **ENVIRONMENT VARIABLES** section), then after processing all expressions and files, bc(1) will exit, unless **-** (**stdin**) was given as an argument at least once to **-f** or **-\-file**, whether on the command-line or in **BC_ENV_ARGS**. However, if any other **-e**, **-\-expression**, **-f**, or **-\-file** arguments are given after **-f-** or equivalent is given, bc(1) will give a fatal error and exit. This is a **non-portable extension**. **-f** *file*, **-\-file**=*file* : Reads in *file* and evaluates it, line by line, as though it were read through **stdin**. If expressions are also given (see above), the expressions are evaluated in the order given. If this option is given on the command-line (i.e., not in **BC_ENV_ARGS**, see the **ENVIRONMENT VARIABLES** section), then after processing all expressions and files, bc(1) will exit, unless **-** (**stdin**) was given as an argument at least once to **-f** or **-\-file**. However, if any other **-e**, **-\-expression**, **-f**, or **-\-file** arguments are given after **-f-** or equivalent is given, bc(1) will give a fatal error and exit. This is a **non-portable extension**. All long options are **non-portable extensions**. # STDIN If no files or expressions are given by the **-f**, **-\-file**, **-e**, or **-\-expression** options, then bc(1) read from **stdin**. However, there are a few caveats to this. First, **stdin** is evaluated a line at a time. The only exception to this is if the parse cannot complete. That means that starting a string without ending it or starting a function, **if** statement, or loop without ending it will also cause bc(1) to not execute. Second, after an **if** statement, bc(1) doesn't know if an **else** statement will follow, so it will not execute until it knows there will not be an **else** statement. # STDOUT Any non-error output is written to **stdout**. In addition, if history (see the **HISTORY** section) and the prompt (see the **TTY MODE** section) are enabled, both are output to **stdout**. **Note**: Unlike other bc(1) implementations, this bc(1) will issue a fatal error (see the **EXIT STATUS** section) if it cannot write to **stdout**, so if **stdout** is closed, as in **bc >&-**, it will quit with an error. This is done so that bc(1) can report problems when **stdout** is redirected to a file. If there are scripts that depend on the behavior of other bc(1) implementations, it is recommended that those scripts be changed to redirect **stdout** to **/dev/null**. # STDERR Any error output is written to **stderr**. **Note**: Unlike other bc(1) implementations, this bc(1) will issue a fatal error (see the **EXIT STATUS** section) if it cannot write to **stderr**, so if **stderr** is closed, as in **bc 2>&-**, it will quit with an error. This is done so that bc(1) can exit with an error code when **stderr** is redirected to a file. If there are scripts that depend on the behavior of other bc(1) implementations, it is recommended that those scripts be changed to redirect **stderr** to **/dev/null**. # SYNTAX The syntax for bc(1) programs is mostly C-like, with some differences. This bc(1) follows the [POSIX standard][1], which is a much more thorough resource for the language this bc(1) accepts. This section is meant to be a summary and a listing of all the extensions to the standard. In the sections below, **E** means expression, **S** means statement, and **I** means identifier. Identifiers (**I**) start with a lowercase letter and can be followed by any number (up to **BC_NAME_MAX-1**) of lowercase letters (**a-z**), digits (**0-9**), and underscores (**\_**). The regex is **\[a-z\]\[a-z0-9\_\]\***. Identifiers with more than one character (letter) are a **non-portable extension**. **ibase** is a global variable determining how to interpret constant numbers. It is the "input" base, or the number base used for interpreting input numbers. **ibase** is initially **10**. If the **-s** (**-\-standard**) and **-w** (**-\-warn**) flags were not given on the command line, the max allowable value for **ibase** is **36**. Otherwise, it is **16**. The min allowable value for **ibase** is **2**. The max allowable value for **ibase** can be queried in bc(1) programs with the **maxibase()** built-in function. **obase** is a global variable determining how to output results. It is the "output" base, or the number base used for outputting numbers. **obase** is initially **10**. The max allowable value for **obase** is **BC_BASE_MAX** and can be queried in bc(1) programs with the **maxobase()** built-in function. The min allowable value for **obase** is **2**. Values are output in the specified base. The *scale* of an expression is the number of digits in the result of the expression right of the decimal point, and **scale** is a global variable that sets the precision of any operations, with exceptions. **scale** is initially **0**. **scale** cannot be negative. The max allowable value for **scale** is **BC_SCALE_MAX** and can be queried in bc(1) programs with the **maxscale()** built-in function. bc(1) has both *global* variables and *local* variables. All *local* variables are local to the function; they are parameters or are introduced in the **auto** list of a function (see the **FUNCTIONS** section). If a variable is accessed which is not a parameter or in the **auto** list, it is assumed to be *global*. If a parent function has a *local* variable version of a variable that a child function considers *global*, the value of that *global* variable in the child function is the value of the variable in the parent function, not the value of the actual *global* variable. All of the above applies to arrays as well. The value of a statement that is an expression (i.e., any of the named expressions or operands) is printed unless the lowest precedence operator is an assignment operator *and* the expression is notsurrounded by parentheses. The value that is printed is also assigned to the special variable **last**. A single dot (**.**) may also be used as a synonym for **last**. These are **non-portable extensions**. Either semicolons or newlines may separate statements. ## Comments There are two kinds of comments: 1. Block comments are enclosed in **/\*** and **\*/**. 2. Line comments go from **#** until, and not including, the next newline. This is a **non-portable extension**. ## Named Expressions The following are named expressions in bc(1): 1. Variables: **I** 2. Array Elements: **I[E]** 3. **ibase** 4. **obase** 5. **scale** 6. **last** or a single dot (**.**) Number 6 is a **non-portable extension**. Variables and arrays do not interfere; users can have arrays named the same as variables. This also applies to functions (see the **FUNCTIONS** section), so a user can have a variable, array, and function that all have the same name, and they will not shadow each other, whether inside of functions or not. Named expressions are required as the operand of **increment**/**decrement** operators and as the left side of **assignment** operators (see the *Operators* subsection). ## Operands The following are valid operands in bc(1): 1. Numbers (see the *Numbers* subsection below). 2. Array indices (**I[E]**). 3. **(E)**: The value of **E** (used to change precedence). 4. **sqrt(E)**: The square root of **E**. **E** must be non-negative. 5. **length(E)**: The number of significant decimal digits in **E**. Returns **1** for **0** with no decimal places. If given a string, the length of the string is returned. Passing a string to **length(E)** is a **non-portable extension**. 6. **length(I[])**: The number of elements in the array **I**. This is a **non-portable extension**. 7. **scale(E)**: The *scale* of **E**. 8. **abs(E)**: The absolute value of **E**. This is a **non-portable extension**. 9. **modexp(E, E, E)**: Modular exponentiation, where the first expression is the base, the second is the exponent, and the third is the modulus. All three values must be integers. The second argument must be non-negative. The third argument must be non-zero. This is a **non-portable extension**. 10. **divmod(E, E, I[])**: Division and modulus in one operation. This is for optimization. The first expression is the dividend, and the second is the divisor, which must be non-zero. The return value is the quotient, and the modulus is stored in index **0** of the provided array (the last argument). This is a **non-portable extension**. 11. **asciify(E)**: If **E** is a string, returns a string that is the first letter of its argument. If it is a number, calculates the number mod **256** and returns that number as a one-character string. This is a **non-portable extension**. 12. **I()**, **I(E)**, **I(E, E)**, and so on, where **I** is an identifier for a non-**void** function (see the *Void Functions* subsection of the **FUNCTIONS** section). The **E** argument(s) may also be arrays of the form **I[]**, which will automatically be turned into array references (see the *Array References* subsection of the **FUNCTIONS** section) if the corresponding parameter in the function definition is an array reference. 13. **read()**: Reads a line from **stdin** and uses that as an expression. The result of that expression is the result of the **read()** operand. This is a **non-portable extension**. 14. **maxibase()**: The max allowable **ibase**. This is a **non-portable extension**. 15. **maxobase()**: The max allowable **obase**. This is a **non-portable extension**. 16. **maxscale()**: The max allowable **scale**. This is a **non-portable extension**. 17. **line_length()**: The line length set with **BC_LINE_LENGTH** (see the **ENVIRONMENT VARIABLES** section). This is a **non-portable extension**. 18. **global_stacks()**: **0** if global stacks are not enabled with the **-g** or **-\-global-stacks** options, non-zero otherwise. See the **OPTIONS** section. This is a **non-portable extension**. 19. **leading_zero()**: **0** if leading zeroes are not enabled with the **-z** or **--leading-zeroes** options, non-zero otherwise. See the **OPTIONS** section. This is a **non-portable extension**. ## Numbers Numbers are strings made up of digits, uppercase letters, and at most **1** period for a radix. Numbers can have up to **BC_NUM_MAX** digits. Uppercase letters are equal to **9** + their position in the alphabet (i.e., **A** equals **10**, or **9+1**). If a digit or letter makes no sense with the current value of **ibase**, they are set to the value of the highest valid digit in **ibase**. Single-character numbers (i.e., **A** alone) take the value that they would have if they were valid digits, regardless of the value of **ibase**. This means that **A** alone always equals decimal **10** and **Z** alone always equals decimal **35**. ## Operators The following arithmetic and logical operators can be used. They are listed in order of decreasing precedence. Operators in the same group have the same precedence. **++** **-\-** : Type: Prefix and Postfix Associativity: None Description: **increment**, **decrement** **-** **!** : Type: Prefix Associativity: None Description: **negation**, **boolean not** **\^** : Type: Binary Associativity: Right Description: **power** **\*** **/** **%** : Type: Binary Associativity: Left Description: **multiply**, **divide**, **modulus** **+** **-** : Type: Binary Associativity: Left Description: **add**, **subtract** **=** **+=** **-=** **\*=** **/=** **%=** **\^=** : Type: Binary Associativity: Right Description: **assignment** **==** **\<=** **\>=** **!=** **\<** **\>** : Type: Binary Associativity: Left Description: **relational** **&&** : Type: Binary Associativity: Left Description: **boolean and** **||** : Type: Binary Associativity: Left Description: **boolean or** The operators will be described in more detail below. **++** **-\-** : The prefix and postfix **increment** and **decrement** operators behave exactly like they would in C. They require a named expression (see the *Named Expressions* subsection) as an operand. The prefix versions of these operators are more efficient; use them where possible. **-** : The **negation** operator returns **0** if a user attempts to negate any expression with the value **0**. Otherwise, a copy of the expression with its sign flipped is returned. **!** : The **boolean not** operator returns **1** if the expression is **0**, or **0** otherwise. This is a **non-portable extension**. **\^** : The **power** operator (not the **exclusive or** operator, as it would be in C) takes two expressions and raises the first to the power of the value of the second. The *scale* of the result is equal to **scale**. The second expression must be an integer (no *scale*), and if it is negative, the first value must be non-zero. **\*** : The **multiply** operator takes two expressions, multiplies them, and returns the product. If **a** is the *scale* of the first expression and **b** is the *scale* of the second expression, the *scale* of the result is equal to **min(a+b,max(scale,a,b))** where **min()** and **max()** return the obvious values. **/** : The **divide** operator takes two expressions, divides them, and returns the quotient. The *scale* of the result shall be the value of **scale**. The second expression must be non-zero. **%** : The **modulus** operator takes two expressions, **a** and **b**, and evaluates them by 1) Computing **a/b** to current **scale** and 2) Using the result of step 1 to calculate **a-(a/b)\*b** to *scale* **max(scale+scale(b),scale(a))**. The second expression must be non-zero. **+** : The **add** operator takes two expressions, **a** and **b**, and returns the sum, with a *scale* equal to the max of the *scale*s of **a** and **b**. **-** : The **subtract** operator takes two expressions, **a** and **b**, and returns the difference, with a *scale* equal to the max of the *scale*s of **a** and **b**. **=** **+=** **-=** **\*=** **/=** **%=** **\^=** : The **assignment** operators take two expressions, **a** and **b** where **a** is a named expression (see the *Named Expressions* subsection). For **=**, **b** is copied and the result is assigned to **a**. For all others, **a** and **b** are applied as operands to the corresponding arithmetic operator and the result is assigned to **a**. **==** **\<=** **\>=** **!=** **\<** **\>** : The **relational** operators compare two expressions, **a** and **b**, and if the relation holds, according to C language semantics, the result is **1**. Otherwise, it is **0**. Note that unlike in C, these operators have a lower precedence than the **assignment** operators, which means that **a=b\>c** is interpreted as **(a=b)\>c**. Also, unlike the [standard][1] requires, these operators can appear anywhere any other expressions can be used. This allowance is a **non-portable extension**. **&&** : The **boolean and** operator takes two expressions and returns **1** if both expressions are non-zero, **0** otherwise. This is *not* a short-circuit operator. This is a **non-portable extension**. **||** : The **boolean or** operator takes two expressions and returns **1** if one of the expressions is non-zero, **0** otherwise. This is *not* a short-circuit operator. This is a **non-portable extension**. ## Statements The following items are statements: 1. **E** 2. **{** **S** **;** ... **;** **S** **}** 3. **if** **(** **E** **)** **S** 4. **if** **(** **E** **)** **S** **else** **S** 5. **while** **(** **E** **)** **S** 6. **for** **(** **E** **;** **E** **;** **E** **)** **S** 7. An empty statement 8. **break** 9. **continue** 10. **quit** 11. **halt** 12. **limits** 13. A string of characters, enclosed in double quotes 14. **print** **E** **,** ... **,** **E** 15. **stream** **E** **,** ... **,** **E** 16. **I()**, **I(E)**, **I(E, E)**, and so on, where **I** is an identifier for a **void** function (see the *Void Functions* subsection of the **FUNCTIONS** section). The **E** argument(s) may also be arrays of the form **I[]**, which will automatically be turned into array references (see the *Array References* subsection of the **FUNCTIONS** section) if the corresponding parameter in the function definition is an array reference. Numbers 4, 9, 11, 12, 14, 15, and 16 are **non-portable extensions**. Also, as a **non-portable extension**, any or all of the expressions in the header of a for loop may be omitted. If the condition (second expression) is omitted, it is assumed to be a constant **1**. The **break** statement causes a loop to stop iterating and resume execution immediately following a loop. This is only allowed in loops. The **continue** statement causes a loop iteration to stop early and returns to the start of the loop, including testing the loop condition. This is only allowed in loops. The **if** **else** statement does the same thing as in C. The **quit** statement causes bc(1) to quit, even if it is on a branch that will not be executed (it is a compile-time command). The **halt** statement causes bc(1) to quit, if it is executed. (Unlike **quit** if it is on a branch of an **if** statement that is not executed, bc(1) does not quit.) The **limits** statement prints the limits that this bc(1) is subject to. This is like the **quit** statement in that it is a compile-time command. An expression by itself is evaluated and printed, followed by a newline. ## Strings If strings appear as a statement by themselves, they are printed without a trailing newline. In addition to appearing as a lone statement by themselves, strings can be assigned to variables and array elements. They can also be passed to functions in variable parameters. If any statement that expects a string is given a variable that had a string assigned to it, the statement acts as though it had received a string. If any math operation is attempted on a string or a variable or array element that has been assigned a string, an error is raised, and bc(1) resets (see the **RESET** section). Assigning strings to variables and array elements and passing them to functions are **non-portable extensions**. ## Print Statement The "expressions" in a **print** statement may also be strings. If they are, there are backslash escape sequences that are interpreted specially. What those sequences are, and what they cause to be printed, are shown below: **\\a**: **\\a** **\\b**: **\\b** **\\\\**: **\\** **\\e**: **\\** **\\f**: **\\f** **\\n**: **\\n** **\\q**: **"** **\\r**: **\\r** **\\t**: **\\t** Any other character following a backslash causes the backslash and character to be printed as-is. Any non-string expression in a print statement shall be assigned to **last**, like any other expression that is printed. ## Stream Statement The "expressions in a **stream** statement may also be strings. If a **stream** statement is given a string, it prints the string as though the string had appeared as its own statement. In other words, the **stream** statement prints strings normally, without a newline. If a **stream** statement is given a number, a copy of it is truncated and its absolute value is calculated. The result is then printed as though **obase** is **256** and each digit is interpreted as an 8-bit ASCII character, making it a byte stream. ## Order of Evaluation All expressions in a statment are evaluated left to right, except as necessary to maintain order of operations. This means, for example, assuming that **i** is equal to **0**, in the expression a[i++] = i++ the first (or 0th) element of **a** is set to **1**, and **i** is equal to **2** at the end of the expression. This includes function arguments. Thus, assuming **i** is equal to **0**, this means that in the expression x(i++, i++) the first argument passed to **x()** is **0**, and the second argument is **1**, while **i** is equal to **2** before the function starts executing. # FUNCTIONS Function definitions are as follows: ``` define I(I,...,I){ auto I,...,I S;...;S return(E) } ``` Any **I** in the parameter list or **auto** list may be replaced with **I[]** to make a parameter or **auto** var an array, and any **I** in the parameter list may be replaced with **\*I[]** to make a parameter an array reference. Callers of functions that take array references should not put an asterisk in the call; they must be called with just **I[]** like normal array parameters and will be automatically converted into references. As a **non-portable extension**, the opening brace of a **define** statement may appear on the next line. As a **non-portable extension**, the return statement may also be in one of the following forms: 1. **return** 2. **return** **(** **)** 3. **return** **E** The first two, or not specifying a **return** statement, is equivalent to **return (0)**, unless the function is a **void** function (see the *Void Functions* subsection below). ## Void Functions Functions can also be **void** functions, defined as follows: ``` define void I(I,...,I){ auto I,...,I S;...;S return } ``` They can only be used as standalone expressions, where such an expression would be printed alone, except in a print statement. Void functions can only use the first two **return** statements listed above. They can also omit the return statement entirely. The word "void" is not treated as a keyword; it is still possible to have variables, arrays, and functions named **void**. The word "void" is only treated specially right after the **define** keyword. This is a **non-portable extension**. ## Array References For any array in the parameter list, if the array is declared in the form ``` *I[] ``` it is a **reference**. Any changes to the array in the function are reflected, when the function returns, to the array that was passed in. Other than this, all function arguments are passed by value. This is a **non-portable extension**. # LIBRARY All of the functions below are available when the **-l** or **-\-mathlib** command-line flags are given. ## Standard Library The [standard][1] defines the following functions for the math library: **s(x)** : Returns the sine of **x**, which is assumed to be in radians. This is a transcendental function (see the *Transcendental Functions* subsection below). **c(x)** : Returns the cosine of **x**, which is assumed to be in radians. This is a transcendental function (see the *Transcendental Functions* subsection below). **a(x)** : Returns the arctangent of **x**, in radians. This is a transcendental function (see the *Transcendental Functions* subsection below). **l(x)** : Returns the natural logarithm of **x**. This is a transcendental function (see the *Transcendental Functions* subsection below). **e(x)** : Returns the mathematical constant **e** raised to the power of **x**. This is a transcendental function (see the *Transcendental Functions* subsection below). **j(x, n)** : Returns the bessel integer order **n** (truncated) of **x**. This is a transcendental function (see the *Transcendental Functions* subsection below). ## Transcendental Functions All transcendental functions can return slightly inaccurate results (up to 1 [ULP][4]). This is unavoidable, and [this article][5] explains why it is impossible and unnecessary to calculate exact results for the transcendental functions. Because of the possible inaccuracy, I recommend that users call those functions with the precision (**scale**) set to at least 1 higher than is necessary. If exact results are *absolutely* required, users can double the precision (**scale**) and then truncate. The transcendental functions in the standard math library are: * **s(x)** * **c(x)** * **a(x)** * **l(x)** * **e(x)** * **j(x, n)** # RESET When bc(1) encounters an error or a signal that it has a non-default handler for, it resets. This means that several things happen. First, any functions that are executing are stopped and popped off the stack. The behavior is not unlike that of exceptions in programming languages. Then the execution point is set so that any code waiting to execute (after all functions returned) is skipped. Thus, when bc(1) resets, it skips any remaining code waiting to be executed. Then, if it is interactive mode, and the error was not a fatal error (see the **EXIT STATUS** section), it asks for more input; otherwise, it exits with the appropriate return code. Note that this reset behavior is different from the GNU bc(1), which attempts to start executing the statement right after the one that caused an error. # PERFORMANCE Most bc(1) implementations use **char** types to calculate the value of **1** decimal digit at a time, but that can be slow. This bc(1) does something different. It uses large integers to calculate more than **1** decimal digit at a time. If built in a environment where **BC_LONG_BIT** (see the **LIMITS** section) is **64**, then each integer has **9** decimal digits. If built in an environment where **BC_LONG_BIT** is **32** then each integer has **4** decimal digits. This value (the number of decimal digits per large integer) is called **BC_BASE_DIGS**. The actual values of **BC_LONG_BIT** and **BC_BASE_DIGS** can be queried with the **limits** statement. In addition, this bc(1) uses an even larger integer for overflow checking. This integer type depends on the value of **BC_LONG_BIT**, but is always at least twice as large as the integer type used to store digits. # LIMITS The following are the limits on bc(1): **BC_LONG_BIT** : The number of bits in the **long** type in the environment where bc(1) was built. This determines how many decimal digits can be stored in a single large integer (see the **PERFORMANCE** section). **BC_BASE_DIGS** : The number of decimal digits per large integer (see the **PERFORMANCE** section). Depends on **BC_LONG_BIT**. **BC_BASE_POW** : The max decimal number that each large integer can store (see **BC_BASE_DIGS**) plus **1**. Depends on **BC_BASE_DIGS**. **BC_OVERFLOW_MAX** : The max number that the overflow type (see the **PERFORMANCE** section) can hold. Depends on **BC_LONG_BIT**. **BC_BASE_MAX** : The maximum output base. Set at **BC_BASE_POW**. **BC_DIM_MAX** : The maximum size of arrays. Set at **SIZE_MAX-1**. **BC_SCALE_MAX** : The maximum **scale**. Set at **BC_OVERFLOW_MAX-1**. **BC_STRING_MAX** : The maximum length of strings. Set at **BC_OVERFLOW_MAX-1**. **BC_NAME_MAX** : The maximum length of identifiers. Set at **BC_OVERFLOW_MAX-1**. **BC_NUM_MAX** : The maximum length of a number (in decimal digits), which includes digits after the decimal point. Set at **BC_OVERFLOW_MAX-1**. Exponent : The maximum allowable exponent (positive or negative). Set at **BC_OVERFLOW_MAX**. Number of vars : The maximum number of vars/arrays. Set at **SIZE_MAX-1**. The actual values can be queried with the **limits** statement. These limits are meant to be effectively non-existent; the limits are so large (at least on 64-bit machines) that there should not be any point at which they become a problem. In fact, memory should be exhausted before these limits should be hit. # ENVIRONMENT VARIABLES bc(1) recognizes the following environment variables: **POSIXLY_CORRECT** : If this variable exists (no matter the contents), bc(1) behaves as if the **-s** option was given. **BC_ENV_ARGS** : This is another way to give command-line arguments to bc(1). They should be in the same format as all other command-line arguments. These are always processed first, so any files given in **BC_ENV_ARGS** will be processed before arguments and files given on the command-line. This gives the user the ability to set up "standard" options and files to be used at every invocation. The most useful thing for such files to contain would be useful functions that the user might want every time bc(1) runs. The code that parses **BC_ENV_ARGS** will correctly handle quoted arguments, but it does not understand escape sequences. For example, the string **"/home/gavin/some bc file.bc"** will be correctly parsed, but the string **"/home/gavin/some \"bc\" file.bc"** will include the backslashes. The quote parsing will handle either kind of quotes, **'** or **"**. Thus, if you have a file with any number of single quotes in the name, you can use double quotes as the outside quotes, as in **"some 'bc' file.bc"**, and vice versa if you have a file with double quotes. However, handling a file with both kinds of quotes in **BC_ENV_ARGS** is not supported due to the complexity of the parsing, though such files are still supported on the command-line where the parsing is done by the shell. **BC_LINE_LENGTH** : If this environment variable exists and contains an integer that is greater than **1** and is less than **UINT16_MAX** (**2\^16-1**), bc(1) will output lines to that length, including the backslash (**\\**). The default line length is **70**. The special value of **0** will disable line length checking and print numbers without regard to line length and without backslashes and newlines. **BC_BANNER** : If this environment variable exists and contains an integer, then a non-zero value activates the copyright banner when bc(1) is in interactive mode, while zero deactivates it. If bc(1) is not in interactive mode (see the **INTERACTIVE MODE** section), then this environment variable has no effect because bc(1) does not print the banner when not in interactive mode. This environment variable overrides the default, which can be queried with the **-h** or **-\-help** options. **BC_SIGINT_RESET** : If bc(1) is not in interactive mode (see the **INTERACTIVE MODE** section), then this environment variable has no effect because bc(1) exits on **SIGINT** when not in interactive mode. However, when bc(1) is in interactive mode, then if this environment variable exists and contains an integer, a non-zero value makes bc(1) reset on **SIGINT**, rather than exit, and zero makes bc(1) exit. If this environment variable exists and is *not* an integer, then bc(1) will exit on **SIGINT**. This environment variable overrides the default, which can be queried with the **-h** or **-\-help** options. **BC_TTY_MODE** : If TTY mode is *not* available (see the **TTY MODE** section), then this environment variable has no effect. However, when TTY mode is available, then if this environment variable exists and contains an integer, then a non-zero value makes bc(1) use TTY mode, and zero makes bc(1) not use TTY mode. This environment variable overrides the default, which can be queried with the **-h** or **-\-help** options. **BC_PROMPT** : If TTY mode is *not* available (see the **TTY MODE** section), then this environment variable has no effect. However, when TTY mode is available, then if this environment variable exists and contains an integer, a non-zero value makes bc(1) use a prompt, and zero or a non-integer makes bc(1) not use a prompt. If this environment variable does not exist and **BC_TTY_MODE** does, then the value of the **BC_TTY_MODE** environment variable is used. This environment variable and the **BC_TTY_MODE** environment variable override the default, which can be queried with the **-h** or **-\-help** options. +**BC_EXPR_EXIT** + +: If any expressions or expression files are given on the command-line with + **-e**, **-\-expression**, **-f**, or **-\-file**, then if this environment + variable exists and contains an integer, a non-zero value makes bc(1) exit + after executing the expressions and expression files, and a non-zero value + makes bc(1) not exit. + + This environment variable overrides the default, which can be queried with + the **-h** or **-\-help** options. + # EXIT STATUS bc(1) returns the following exit statuses: **0** : No error. **1** : A math error occurred. This follows standard practice of using **1** for expected errors, since math errors will happen in the process of normal execution. Math errors include divide by **0**, taking the square root of a negative number, attempting to convert a negative number to a hardware integer, overflow when converting a number to a hardware integer, overflow when calculating the size of a number, and attempting to use a non-integer where an integer is required. Converting to a hardware integer happens for the second operand of the power (**\^**) operator and the corresponding assignment operator. **2** : A parse error occurred. Parse errors include unexpected **EOF**, using an invalid character, failing to find the end of a string or comment, using a token where it is invalid, giving an invalid expression, giving an invalid print statement, giving an invalid function definition, attempting to assign to an expression that is not a named expression (see the *Named Expressions* subsection of the **SYNTAX** section), giving an invalid **auto** list, having a duplicate **auto**/function parameter, failing to find the end of a code block, attempting to return a value from a **void** function, attempting to use a variable as a reference, and using any extensions when the option **-s** or any equivalents were given. **3** : A runtime error occurred. Runtime errors include assigning an invalid number to any global (**ibase**, **obase**, or **scale**), giving a bad expression to a **read()** call, calling **read()** inside of a **read()** call, type errors, passing the wrong number of arguments to functions, attempting to call an undefined function, and attempting to use a **void** function call as a value in an expression. **4** : A fatal error occurred. Fatal errors include memory allocation errors, I/O errors, failing to open files, attempting to use files that do not have only ASCII characters (bc(1) only accepts ASCII characters), attempting to open a directory as a file, and giving invalid command-line options. The exit status **4** is special; when a fatal error occurs, bc(1) always exits and returns **4**, no matter what mode bc(1) is in. The other statuses will only be returned when bc(1) is not in interactive mode (see the **INTERACTIVE MODE** section), since bc(1) resets its state (see the **RESET** section) and accepts more input when one of those errors occurs in interactive mode. This is also the case when interactive mode is forced by the **-i** flag or **-\-interactive** option. These exit statuses allow bc(1) to be used in shell scripting with error checking, and its normal behavior can be forced by using the **-i** flag or **-\-interactive** option. # INTERACTIVE MODE Per the [standard][1], bc(1) has an interactive mode and a non-interactive mode. Interactive mode is turned on automatically when both **stdin** and **stdout** are hooked to a terminal, but the **-i** flag and **-\-interactive** option can turn it on in other situations. In interactive mode, bc(1) attempts to recover from errors (see the **RESET** section), and in normal execution, flushes **stdout** as soon as execution is done for the current input. bc(1) may also reset on **SIGINT** instead of exit, depending on the contents of, or default for, the **BC_SIGINT_RESET** environment variable (see the **ENVIRONMENT VARIABLES** section). # TTY MODE If **stdin**, **stdout**, and **stderr** are all connected to a TTY, then "TTY mode" is considered to be available, and thus, bc(1) can turn on TTY mode, subject to some settings. If there is the environment variable **BC_TTY_MODE** in the environment (see the **ENVIRONMENT VARIABLES** section), then if that environment variable contains a non-zero integer, bc(1) will turn on TTY mode when **stdin**, **stdout**, and **stderr** are all connected to a TTY. If the **BC_TTY_MODE** environment variable exists but is *not* a non-zero integer, then bc(1) will not turn TTY mode on. If the environment variable **BC_TTY_MODE** does *not* exist, the default setting is used. The default setting can be queried with the **-h** or **-\-help** options. TTY mode is different from interactive mode because interactive mode is required in the [bc(1) specification][1], and interactive mode requires only **stdin** and **stdout** to be connected to a terminal. ## Command-Line History Command-line history is only enabled if TTY mode is, i.e., that **stdin**, **stdout**, and **stderr** are connected to a TTY and the **BC_TTY_MODE** environment variable (see the **ENVIRONMENT VARIABLES** section) and its default do not disable TTY mode. See the **COMMAND LINE HISTORY** section for more information. ## Prompt If TTY mode is available, then a prompt can be enabled. Like TTY mode itself, it can be turned on or off with an environment variable: **BC_PROMPT** (see the **ENVIRONMENT VARIABLES** section). If the environment variable **BC_PROMPT** exists and is a non-zero integer, then the prompt is turned on when **stdin**, **stdout**, and **stderr** are connected to a TTY and the **-P** and **-\-no-prompt** options were not used. The read prompt will be turned on under the same conditions, except that the **-R** and **-\-no-read-prompt** options must also not be used. However, if **BC_PROMPT** does not exist, the prompt can be enabled or disabled with the **BC_TTY_MODE** environment variable, the **-P** and **-\-no-prompt** options, and the **-R** and **-\-no-read-prompt** options. See the **ENVIRONMENT VARIABLES** and **OPTIONS** sections for more details. # SIGNAL HANDLING Sending a **SIGINT** will cause bc(1) to do one of two things. If bc(1) is not in interactive mode (see the **INTERACTIVE MODE** section), or the **BC_SIGINT_RESET** environment variable (see the **ENVIRONMENT VARIABLES** section), or its default, is either not an integer or it is zero, bc(1) will exit. However, if bc(1) is in interactive mode, and the **BC_SIGINT_RESET** or its default is an integer and non-zero, then bc(1) will stop executing the current input and reset (see the **RESET** section) upon receiving a **SIGINT**. Note that "current input" can mean one of two things. If bc(1) is processing input from **stdin** in interactive mode, it will ask for more input. If bc(1) is processing input from a file in interactive mode, it will stop processing the file and start processing the next file, if one exists, or ask for input from **stdin** if no other file exists. This means that if a **SIGINT** is sent to bc(1) as it is executing a file, it can seem as though bc(1) did not respond to the signal since it will immediately start executing the next file. This is by design; most files that users execute when interacting with bc(1) have function definitions, which are quick to parse. If a file takes a long time to execute, there may be a bug in that file. The rest of the files could still be executed without problem, allowing the user to continue. **SIGTERM** and **SIGQUIT** cause bc(1) to clean up and exit, and it uses the default handler for all other signals. The one exception is **SIGHUP**; in that case, and only when bc(1) is in TTY mode (see the **TTY MODE** section), a **SIGHUP** will cause bc(1) to clean up and exit. # COMMAND LINE HISTORY bc(1) supports interactive command-line editing. If bc(1) can be in TTY mode (see the **TTY MODE** section), history can be enabled. This means that command-line history can only be enabled when **stdin**, **stdout**, and **stderr** are all connected to a TTY. Like TTY mode itself, it can be turned on or off with the environment variable **BC_TTY_MODE** (see the **ENVIRONMENT VARIABLES** section). If history is enabled, previous lines can be recalled and edited with the arrow keys. **Note**: tabs are converted to 8 spaces. # SEE ALSO dc(1) # STANDARDS bc(1) is compliant with the [IEEE Std 1003.1-2017 (“POSIX.1-2017”)][1] specification. The flags **-efghiqsvVw**, all long options, and the extensions noted above are extensions to that specification. Note that the specification explicitly says that bc(1) only accepts numbers that use a period (**.**) as a radix point, regardless of the value of **LC_NUMERIC**. # BUGS None are known. Report bugs at https://git.yzena.com/gavin/bc. # AUTHORS Gavin D. Howard and contributors. [1]: https://pubs.opengroup.org/onlinepubs/9699919799/utilities/bc.html [2]: https://www.gnu.org/software/bc/ [3]: https://en.wikipedia.org/wiki/Rounding#Round_half_away_from_zero [4]: https://en.wikipedia.org/wiki/Unit_in_the_last_place [5]: https://people.eecs.berkeley.edu/~wkahan/LOG10HAF.TXT [6]: https://en.wikipedia.org/wiki/Rounding#Rounding_away_from_zero diff --git a/contrib/bc/manuals/bc/H.1 b/contrib/bc/manuals/bc/H.1 index 5f290f12ae32..f6d555943367 100644 --- a/contrib/bc/manuals/bc/H.1 +++ b/contrib/bc/manuals/bc/H.1 @@ -1,2755 +1,2768 @@ .\" .\" SPDX-License-Identifier: BSD-2-Clause .\" .\" Copyright (c) 2018-2021 Gavin D. Howard and contributors. .\" .\" Redistribution and use in source and binary forms, with or without .\" modification, are permitted provided that the following conditions are met: .\" .\" * Redistributions of source code must retain the above copyright notice, .\" this list of conditions and the following disclaimer. .\" .\" * Redistributions in binary form must reproduce the above copyright notice, .\" this list of conditions and the following disclaimer in the documentation .\" and/or other materials provided with the distribution. .\" .\" THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" .\" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE .\" IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE .\" ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE .\" LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR .\" CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF .\" SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS .\" INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN .\" CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) .\" ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE .\" POSSIBILITY OF SUCH DAMAGE. .\" .TH "BC" "1" "June 2021" "Gavin D. Howard" "General Commands Manual" .SH NAME .PP bc - arbitrary-precision decimal arithmetic language and calculator .SH SYNOPSIS .PP \f[B]bc\f[R] [\f[B]-ghilPqRsvVw\f[R]] [\f[B]--global-stacks\f[R]] [\f[B]--help\f[R]] [\f[B]--interactive\f[R]] [\f[B]--mathlib\f[R]] [\f[B]--no-prompt\f[R]] [\f[B]--no-read-prompt\f[R]] [\f[B]--quiet\f[R]] [\f[B]--standard\f[R]] [\f[B]--warn\f[R]] [\f[B]--version\f[R]] [\f[B]-e\f[R] \f[I]expr\f[R]] [\f[B]--expression\f[R]=\f[I]expr\f[R]\&...] [\f[B]-f\f[R] \f[I]file\f[R]\&...] [\f[B]--file\f[R]=\f[I]file\f[R]\&...] [\f[I]file\f[R]\&...] .SH DESCRIPTION .PP bc(1) is an interactive processor for a language first standardized in 1991 by POSIX. (The current standard is here (https://pubs.opengroup.org/onlinepubs/9699919799/utilities/bc.html).) The language provides unlimited precision decimal arithmetic and is somewhat C-like, but there are differences. Such differences will be noted in this document. .PP After parsing and handling options, this bc(1) reads any files given on the command line and executes them before reading from \f[B]stdin\f[R]. .PP This bc(1) is a drop-in replacement for \f[I]any\f[R] bc(1), including (and especially) the GNU bc(1). It also has many extensions and extra features beyond other implementations. .PP \f[B]Note\f[R]: If running this bc(1) on \f[I]any\f[R] script meant for another bc(1) gives a parse error, it is probably because a word this bc(1) reserves as a keyword is used as the name of a function, variable, or array. To fix that, use the command-line option \f[B]-r\f[R] \f[I]keyword\f[R], where \f[I]keyword\f[R] is the keyword that is used as a name in the script. For more information, see the \f[B]OPTIONS\f[R] section. .PP If parsing scripts meant for other bc(1) implementations still does not work, that is a bug and should be reported. See the \f[B]BUGS\f[R] section. .SH OPTIONS .PP The following are the options that bc(1) accepts. .TP \f[B]-g\f[R], \f[B]--global-stacks\f[R] Turns the globals \f[B]ibase\f[R], \f[B]obase\f[R], \f[B]scale\f[R], and \f[B]seed\f[R] into stacks. .RS .PP This has the effect that a copy of the current value of all four are pushed onto a stack for every function call, as well as popped when every function returns. This means that functions can assign to any and all of those globals without worrying that the change will affect other functions. Thus, a hypothetical function named \f[B]output(x,b)\f[R] that simply printed \f[B]x\f[R] in base \f[B]b\f[R] could be written like this: .IP .nf \f[C] define void output(x, b) { obase=b x } \f[R] .fi .PP instead of like this: .IP .nf \f[C] define void output(x, b) { auto c c=obase obase=b x obase=c } \f[R] .fi .PP This makes writing functions much easier. .PP (\f[B]Note\f[R]: the function \f[B]output(x,b)\f[R] exists in the extended math library. See the \f[B]LIBRARY\f[R] section.) .PP However, since using this flag means that functions cannot set \f[B]ibase\f[R], \f[B]obase\f[R], \f[B]scale\f[R], or \f[B]seed\f[R] globally, functions that are made to do so cannot work anymore. There are two possible use cases for that, and each has a solution. .PP First, if a function is called on startup to turn bc(1) into a number converter, it is possible to replace that capability with various shell aliases. Examples: .IP .nf \f[C] alias d2o=\[dq]bc -e ibase=A -e obase=8\[dq] alias h2b=\[dq]bc -e ibase=G -e obase=2\[dq] \f[R] .fi .PP Second, if the purpose of a function is to set \f[B]ibase\f[R], \f[B]obase\f[R], \f[B]scale\f[R], or \f[B]seed\f[R] globally for any other purpose, it could be split into one to four functions (based on how many globals it sets) and each of those functions could return the desired value for a global. .PP For functions that set \f[B]seed\f[R], the value assigned to \f[B]seed\f[R] is not propagated to parent functions. This means that the sequence of pseudo-random numbers that they see will not be the same sequence of pseudo-random numbers that any parent sees. This is only the case once \f[B]seed\f[R] has been set. .PP If a function desires to not affect the sequence of pseudo-random numbers of its parents, but wants to use the same \f[B]seed\f[R], it can use the following line: .IP .nf \f[C] seed = seed \f[R] .fi .PP If the behavior of this option is desired for every run of bc(1), then users could make sure to define \f[B]BC_ENV_ARGS\f[R] and include this option (see the \f[B]ENVIRONMENT VARIABLES\f[R] section for more details). .PP If \f[B]-s\f[R], \f[B]-w\f[R], or any equivalents are used, this option is ignored. .PP This is a \f[B]non-portable extension\f[R]. .RE .TP \f[B]-h\f[R], \f[B]--help\f[R] Prints a usage message and quits. .TP \f[B]-i\f[R], \f[B]--interactive\f[R] Forces interactive mode. (See the \f[B]INTERACTIVE MODE\f[R] section.) .RS .PP This is a \f[B]non-portable extension\f[R]. .RE .TP \f[B]-L\f[R], \f[B]--no-line-length\f[R] Disables line length checking and prints numbers without backslashes and newlines. In other words, this option sets \f[B]BC_LINE_LENGTH\f[R] to \f[B]0\f[R] (see the \f[B]ENVIRONMENT VARIABLES\f[R] section). .RS .PP This is a \f[B]non-portable extension\f[R]. .RE .TP \f[B]-l\f[R], \f[B]--mathlib\f[R] Sets \f[B]scale\f[R] (see the \f[B]SYNTAX\f[R] section) to \f[B]20\f[R] and loads the included math library and the extended math library before running any code, including any expressions or files specified on the command line. .RS .PP To learn what is in the libraries, see the \f[B]LIBRARY\f[R] section. .RE .TP \f[B]-P\f[R], \f[B]--no-prompt\f[R] Disables the prompt in TTY mode. (The prompt is only enabled in TTY mode. See the \f[B]TTY MODE\f[R] section.) This is mostly for those users that do not want a prompt or are not used to having them in bc(1). Most of those users would want to put this option in \f[B]BC_ENV_ARGS\f[R] (see the \f[B]ENVIRONMENT VARIABLES\f[R] section). .RS .PP These options override the \f[B]BC_PROMPT\f[R] and \f[B]BC_TTY_MODE\f[R] environment variables (see the \f[B]ENVIRONMENT VARIABLES\f[R] section). .PP This is a \f[B]non-portable extension\f[R]. .RE .TP \f[B]-R\f[R], \f[B]--no-read-prompt\f[R] Disables the read prompt in TTY mode. (The read prompt is only enabled in TTY mode. See the \f[B]TTY MODE\f[R] section.) This is mostly for those users that do not want a read prompt or are not used to having them in bc(1). Most of those users would want to put this option in \f[B]BC_ENV_ARGS\f[R] (see the \f[B]ENVIRONMENT VARIABLES\f[R] section). This option is also useful in hash bang lines of bc(1) scripts that prompt for user input. .RS .PP This option does not disable the regular prompt because the read prompt is only used when the \f[B]read()\f[R] built-in function is called. .PP These options \f[I]do\f[R] override the \f[B]BC_PROMPT\f[R] and \f[B]BC_TTY_MODE\f[R] environment variables (see the \f[B]ENVIRONMENT VARIABLES\f[R] section), but only for the read prompt. .PP This is a \f[B]non-portable extension\f[R]. .RE .TP \f[B]-r\f[R] \f[I]keyword\f[R], \f[B]--redefine\f[R]=\f[I]keyword\f[R] Redefines \f[I]keyword\f[R] in order to allow it to be used as a function, variable, or array name. This is useful when this bc(1) gives parse errors when parsing scripts meant for other bc(1) implementations. .RS .PP The keywords this bc(1) allows to be redefined are: .IP \[bu] 2 \f[B]abs\f[R] .IP \[bu] 2 \f[B]asciify\f[R] .IP \[bu] 2 \f[B]continue\f[R] .IP \[bu] 2 \f[B]divmod\f[R] .IP \[bu] 2 \f[B]else\f[R] .IP \[bu] 2 \f[B]halt\f[R] .IP \[bu] 2 \f[B]irand\f[R] .IP \[bu] 2 \f[B]last\f[R] .IP \[bu] 2 \f[B]limits\f[R] .IP \[bu] 2 \f[B]maxibase\f[R] .IP \[bu] 2 \f[B]maxobase\f[R] .IP \[bu] 2 \f[B]maxrand\f[R] .IP \[bu] 2 \f[B]maxscale\f[R] .IP \[bu] 2 \f[B]modexp\f[R] .IP \[bu] 2 \f[B]print\f[R] .IP \[bu] 2 \f[B]rand\f[R] .IP \[bu] 2 \f[B]read\f[R] .IP \[bu] 2 \f[B]seed\f[R] .IP \[bu] 2 \f[B]stream\f[R] .PP If any of those keywords are used as a function, variable, or array name in a script, use this option with the keyword as the argument. If multiple are used, use this option for all of them; it can be used multiple times. .PP Keywords are \f[I]not\f[R] redefined when parsing the builtin math library (see the \f[B]LIBRARY\f[R] section). .PP It is a fatal error to redefine keywords mandated by the POSIX standard. It is a fatal error to attempt to redefine words that this bc(1) does not reserve as keywords. .RE .TP \f[B]-q\f[R], \f[B]--quiet\f[R] This option is for compatibility with the GNU bc(1) (https://www.gnu.org/software/bc/); it is a no-op. Without this option, GNU bc(1) prints a copyright header. This bc(1) only prints the copyright header if one or more of the \f[B]-v\f[R], \f[B]-V\f[R], or \f[B]--version\f[R] options are given. .RS .PP This is a \f[B]non-portable extension\f[R]. .RE .TP \f[B]-s\f[R], \f[B]--standard\f[R] Process exactly the language defined by the standard (https://pubs.opengroup.org/onlinepubs/9699919799/utilities/bc.html) and error if any extensions are used. .RS .PP This is a \f[B]non-portable extension\f[R]. .RE .TP \f[B]-v\f[R], \f[B]-V\f[R], \f[B]--version\f[R] Print the version information (copyright header) and exit. .RS .PP This is a \f[B]non-portable extension\f[R]. .RE .TP \f[B]-w\f[R], \f[B]--warn\f[R] Like \f[B]-s\f[R] and \f[B]--standard\f[R], except that warnings (and not errors) are printed for non-standard extensions and execution continues normally. .RS .PP This is a \f[B]non-portable extension\f[R]. .RE .TP \f[B]-z\f[R], \f[B]--leading-zeroes\f[R] Makes bc(1) print all numbers greater than \f[B]-1\f[R] and less than \f[B]1\f[R], and not equal to \f[B]0\f[R], with a leading zero. .RS .PP This can be set for individual numbers with the \f[B]plz(x)\f[R], plznl(x)**, \f[B]pnlz(x)\f[R], and \f[B]pnlznl(x)\f[R] functions in the extended math library (see the \f[B]LIBRARY\f[R] section). .PP This is a \f[B]non-portable extension\f[R]. .RE .TP \f[B]-e\f[R] \f[I]expr\f[R], \f[B]--expression\f[R]=\f[I]expr\f[R] Evaluates \f[I]expr\f[R]. If multiple expressions are given, they are evaluated in order. If files are given as well (see below), the expressions and files are evaluated in the order given. This means that if a file is given before an expression, the file is read in and evaluated first. .RS .PP If this option is given on the command-line (i.e., not in \f[B]BC_ENV_ARGS\f[R], see the \f[B]ENVIRONMENT VARIABLES\f[R] section), then after processing all expressions and files, bc(1) will exit, unless \f[B]-\f[R] (\f[B]stdin\f[R]) was given as an argument at least once to \f[B]-f\f[R] or \f[B]--file\f[R], whether on the command-line or in \f[B]BC_ENV_ARGS\f[R]. However, if any other \f[B]-e\f[R], \f[B]--expression\f[R], \f[B]-f\f[R], or \f[B]--file\f[R] arguments are given after \f[B]-f-\f[R] or equivalent is given, bc(1) will give a fatal error and exit. .PP This is a \f[B]non-portable extension\f[R]. .RE .TP \f[B]-f\f[R] \f[I]file\f[R], \f[B]--file\f[R]=\f[I]file\f[R] Reads in \f[I]file\f[R] and evaluates it, line by line, as though it were read through \f[B]stdin\f[R]. If expressions are also given (see above), the expressions are evaluated in the order given. .RS .PP If this option is given on the command-line (i.e., not in \f[B]BC_ENV_ARGS\f[R], see the \f[B]ENVIRONMENT VARIABLES\f[R] section), then after processing all expressions and files, bc(1) will exit, unless \f[B]-\f[R] (\f[B]stdin\f[R]) was given as an argument at least once to \f[B]-f\f[R] or \f[B]--file\f[R]. However, if any other \f[B]-e\f[R], \f[B]--expression\f[R], \f[B]-f\f[R], or \f[B]--file\f[R] arguments are given after \f[B]-f-\f[R] or equivalent is given, bc(1) will give a fatal error and exit. .PP This is a \f[B]non-portable extension\f[R]. .RE .PP All long options are \f[B]non-portable extensions\f[R]. .SH STDIN .PP If no files or expressions are given by the \f[B]-f\f[R], \f[B]--file\f[R], \f[B]-e\f[R], or \f[B]--expression\f[R] options, then bc(1) read from \f[B]stdin\f[R]. .PP However, there are a few caveats to this. .PP First, \f[B]stdin\f[R] is evaluated a line at a time. The only exception to this is if the parse cannot complete. That means that starting a string without ending it or starting a function, \f[B]if\f[R] statement, or loop without ending it will also cause bc(1) to not execute. .PP Second, after an \f[B]if\f[R] statement, bc(1) doesn\[cq]t know if an \f[B]else\f[R] statement will follow, so it will not execute until it knows there will not be an \f[B]else\f[R] statement. .SH STDOUT .PP Any non-error output is written to \f[B]stdout\f[R]. In addition, if history (see the \f[B]HISTORY\f[R] section) and the prompt (see the \f[B]TTY MODE\f[R] section) are enabled, both are output to \f[B]stdout\f[R]. .PP \f[B]Note\f[R]: Unlike other bc(1) implementations, this bc(1) will issue a fatal error (see the \f[B]EXIT STATUS\f[R] section) if it cannot write to \f[B]stdout\f[R], so if \f[B]stdout\f[R] is closed, as in \f[B]bc >&-\f[R], it will quit with an error. This is done so that bc(1) can report problems when \f[B]stdout\f[R] is redirected to a file. .PP If there are scripts that depend on the behavior of other bc(1) implementations, it is recommended that those scripts be changed to redirect \f[B]stdout\f[R] to \f[B]/dev/null\f[R]. .SH STDERR .PP Any error output is written to \f[B]stderr\f[R]. .PP \f[B]Note\f[R]: Unlike other bc(1) implementations, this bc(1) will issue a fatal error (see the \f[B]EXIT STATUS\f[R] section) if it cannot write to \f[B]stderr\f[R], so if \f[B]stderr\f[R] is closed, as in \f[B]bc 2>&-\f[R], it will quit with an error. This is done so that bc(1) can exit with an error code when \f[B]stderr\f[R] is redirected to a file. .PP If there are scripts that depend on the behavior of other bc(1) implementations, it is recommended that those scripts be changed to redirect \f[B]stderr\f[R] to \f[B]/dev/null\f[R]. .SH SYNTAX .PP The syntax for bc(1) programs is mostly C-like, with some differences. This bc(1) follows the POSIX standard (https://pubs.opengroup.org/onlinepubs/9699919799/utilities/bc.html), which is a much more thorough resource for the language this bc(1) accepts. This section is meant to be a summary and a listing of all the extensions to the standard. .PP In the sections below, \f[B]E\f[R] means expression, \f[B]S\f[R] means statement, and \f[B]I\f[R] means identifier. .PP Identifiers (\f[B]I\f[R]) start with a lowercase letter and can be followed by any number (up to \f[B]BC_NAME_MAX-1\f[R]) of lowercase letters (\f[B]a-z\f[R]), digits (\f[B]0-9\f[R]), and underscores (\f[B]_\f[R]). The regex is \f[B][a-z][a-z0-9_]*\f[R]. Identifiers with more than one character (letter) are a \f[B]non-portable extension\f[R]. .PP \f[B]ibase\f[R] is a global variable determining how to interpret constant numbers. It is the \[lq]input\[rq] base, or the number base used for interpreting input numbers. \f[B]ibase\f[R] is initially \f[B]10\f[R]. If the \f[B]-s\f[R] (\f[B]--standard\f[R]) and \f[B]-w\f[R] (\f[B]--warn\f[R]) flags were not given on the command line, the max allowable value for \f[B]ibase\f[R] is \f[B]36\f[R]. Otherwise, it is \f[B]16\f[R]. The min allowable value for \f[B]ibase\f[R] is \f[B]2\f[R]. The max allowable value for \f[B]ibase\f[R] can be queried in bc(1) programs with the \f[B]maxibase()\f[R] built-in function. .PP \f[B]obase\f[R] is a global variable determining how to output results. It is the \[lq]output\[rq] base, or the number base used for outputting numbers. \f[B]obase\f[R] is initially \f[B]10\f[R]. The max allowable value for \f[B]obase\f[R] is \f[B]BC_BASE_MAX\f[R] and can be queried in bc(1) programs with the \f[B]maxobase()\f[R] built-in function. The min allowable value for \f[B]obase\f[R] is \f[B]0\f[R]. If \f[B]obase\f[R] is \f[B]0\f[R], values are output in scientific notation, and if \f[B]obase\f[R] is \f[B]1\f[R], values are output in engineering notation. Otherwise, values are output in the specified base. .PP Outputting in scientific and engineering notations are \f[B]non-portable extensions\f[R]. .PP The \f[I]scale\f[R] of an expression is the number of digits in the result of the expression right of the decimal point, and \f[B]scale\f[R] is a global variable that sets the precision of any operations, with exceptions. \f[B]scale\f[R] is initially \f[B]0\f[R]. \f[B]scale\f[R] cannot be negative. The max allowable value for \f[B]scale\f[R] is \f[B]BC_SCALE_MAX\f[R] and can be queried in bc(1) programs with the \f[B]maxscale()\f[R] built-in function. .PP bc(1) has both \f[I]global\f[R] variables and \f[I]local\f[R] variables. All \f[I]local\f[R] variables are local to the function; they are parameters or are introduced in the \f[B]auto\f[R] list of a function (see the \f[B]FUNCTIONS\f[R] section). If a variable is accessed which is not a parameter or in the \f[B]auto\f[R] list, it is assumed to be \f[I]global\f[R]. If a parent function has a \f[I]local\f[R] variable version of a variable that a child function considers \f[I]global\f[R], the value of that \f[I]global\f[R] variable in the child function is the value of the variable in the parent function, not the value of the actual \f[I]global\f[R] variable. .PP All of the above applies to arrays as well. .PP The value of a statement that is an expression (i.e., any of the named expressions or operands) is printed unless the lowest precedence operator is an assignment operator \f[I]and\f[R] the expression is notsurrounded by parentheses. .PP The value that is printed is also assigned to the special variable \f[B]last\f[R]. A single dot (\f[B].\f[R]) may also be used as a synonym for \f[B]last\f[R]. These are \f[B]non-portable extensions\f[R]. .PP Either semicolons or newlines may separate statements. .SS Comments .PP There are two kinds of comments: .IP "1." 3 Block comments are enclosed in \f[B]/*\f[R] and \f[B]*/\f[R]. .IP "2." 3 Line comments go from \f[B]#\f[R] until, and not including, the next newline. This is a \f[B]non-portable extension\f[R]. .SS Named Expressions .PP The following are named expressions in bc(1): .IP "1." 3 Variables: \f[B]I\f[R] .IP "2." 3 Array Elements: \f[B]I[E]\f[R] .IP "3." 3 \f[B]ibase\f[R] .IP "4." 3 \f[B]obase\f[R] .IP "5." 3 \f[B]scale\f[R] .IP "6." 3 \f[B]seed\f[R] .IP "7." 3 \f[B]last\f[R] or a single dot (\f[B].\f[R]) .PP Numbers 6 and 7 are \f[B]non-portable extensions\f[R]. .PP The meaning of \f[B]seed\f[R] is dependent on the current pseudo-random number generator but is guaranteed to not change except for new major versions. .PP The \f[I]scale\f[R] and sign of the value may be significant. .PP If a previously used \f[B]seed\f[R] value is assigned to \f[B]seed\f[R] and used again, the pseudo-random number generator is guaranteed to produce the same sequence of pseudo-random numbers as it did when the \f[B]seed\f[R] value was previously used. .PP The exact value assigned to \f[B]seed\f[R] is not guaranteed to be returned if \f[B]seed\f[R] is queried again immediately. However, if \f[B]seed\f[R] \f[I]does\f[R] return a different value, both values, when assigned to \f[B]seed\f[R], are guaranteed to produce the same sequence of pseudo-random numbers. This means that certain values assigned to \f[B]seed\f[R] will \f[I]not\f[R] produce unique sequences of pseudo-random numbers. The value of \f[B]seed\f[R] will change after any use of the \f[B]rand()\f[R] and \f[B]irand(E)\f[R] operands (see the \f[I]Operands\f[R] subsection below), except if the parameter passed to \f[B]irand(E)\f[R] is \f[B]0\f[R], \f[B]1\f[R], or negative. .PP There is no limit to the length (number of significant decimal digits) or \f[I]scale\f[R] of the value that can be assigned to \f[B]seed\f[R]. .PP Variables and arrays do not interfere; users can have arrays named the same as variables. This also applies to functions (see the \f[B]FUNCTIONS\f[R] section), so a user can have a variable, array, and function that all have the same name, and they will not shadow each other, whether inside of functions or not. .PP Named expressions are required as the operand of \f[B]increment\f[R]/\f[B]decrement\f[R] operators and as the left side of \f[B]assignment\f[R] operators (see the \f[I]Operators\f[R] subsection). .SS Operands .PP The following are valid operands in bc(1): .IP " 1." 4 Numbers (see the \f[I]Numbers\f[R] subsection below). .IP " 2." 4 Array indices (\f[B]I[E]\f[R]). .IP " 3." 4 \f[B](E)\f[R]: The value of \f[B]E\f[R] (used to change precedence). .IP " 4." 4 \f[B]sqrt(E)\f[R]: The square root of \f[B]E\f[R]. \f[B]E\f[R] must be non-negative. .IP " 5." 4 \f[B]length(E)\f[R]: The number of significant decimal digits in \f[B]E\f[R]. Returns \f[B]1\f[R] for \f[B]0\f[R] with no decimal places. If given a string, the length of the string is returned. Passing a string to \f[B]length(E)\f[R] is a \f[B]non-portable extension\f[R]. .IP " 6." 4 \f[B]length(I[])\f[R]: The number of elements in the array \f[B]I\f[R]. This is a \f[B]non-portable extension\f[R]. .IP " 7." 4 \f[B]scale(E)\f[R]: The \f[I]scale\f[R] of \f[B]E\f[R]. .IP " 8." 4 \f[B]abs(E)\f[R]: The absolute value of \f[B]E\f[R]. This is a \f[B]non-portable extension\f[R]. .IP " 9." 4 \f[B]modexp(E, E, E)\f[R]: Modular exponentiation, where the first expression is the base, the second is the exponent, and the third is the modulus. All three values must be integers. The second argument must be non-negative. The third argument must be non-zero. This is a \f[B]non-portable extension\f[R]. .IP "10." 4 \f[B]divmod(E, E, I[])\f[R]: Division and modulus in one operation. This is for optimization. The first expression is the dividend, and the second is the divisor, which must be non-zero. The return value is the quotient, and the modulus is stored in index \f[B]0\f[R] of the provided array (the last argument). This is a \f[B]non-portable extension\f[R]. .IP "11." 4 \f[B]asciify(E)\f[R]: If \f[B]E\f[R] is a string, returns a string that is the first letter of its argument. If it is a number, calculates the number mod \f[B]256\f[R] and returns that number as a one-character string. This is a \f[B]non-portable extension\f[R]. .IP "12." 4 \f[B]I()\f[R], \f[B]I(E)\f[R], \f[B]I(E, E)\f[R], and so on, where \f[B]I\f[R] is an identifier for a non-\f[B]void\f[R] function (see the \f[I]Void Functions\f[R] subsection of the \f[B]FUNCTIONS\f[R] section). The \f[B]E\f[R] argument(s) may also be arrays of the form \f[B]I[]\f[R], which will automatically be turned into array references (see the \f[I]Array References\f[R] subsection of the \f[B]FUNCTIONS\f[R] section) if the corresponding parameter in the function definition is an array reference. .IP "13." 4 \f[B]read()\f[R]: Reads a line from \f[B]stdin\f[R] and uses that as an expression. The result of that expression is the result of the \f[B]read()\f[R] operand. This is a \f[B]non-portable extension\f[R]. .IP "14." 4 \f[B]maxibase()\f[R]: The max allowable \f[B]ibase\f[R]. This is a \f[B]non-portable extension\f[R]. .IP "15." 4 \f[B]maxobase()\f[R]: The max allowable \f[B]obase\f[R]. This is a \f[B]non-portable extension\f[R]. .IP "16." 4 \f[B]maxscale()\f[R]: The max allowable \f[B]scale\f[R]. This is a \f[B]non-portable extension\f[R]. .IP "17." 4 \f[B]line_length()\f[R]: The line length set with \f[B]BC_LINE_LENGTH\f[R] (see the \f[B]ENVIRONMENT VARIABLES\f[R] section). This is a \f[B]non-portable extension\f[R]. .IP "18." 4 \f[B]global_stacks()\f[R]: \f[B]0\f[R] if global stacks are not enabled with the \f[B]-g\f[R] or \f[B]--global-stacks\f[R] options, non-zero otherwise. See the \f[B]OPTIONS\f[R] section. This is a \f[B]non-portable extension\f[R]. .IP "19." 4 \f[B]leading_zero()\f[R]: \f[B]0\f[R] if leading zeroes are not enabled with the \f[B]-z\f[R] or \f[B]\[en]leading-zeroes\f[R] options, non-zero otherwise. See the \f[B]OPTIONS\f[R] section. This is a \f[B]non-portable extension\f[R]. .IP "20." 4 \f[B]rand()\f[R]: A pseudo-random integer between \f[B]0\f[R] (inclusive) and \f[B]BC_RAND_MAX\f[R] (inclusive). Using this operand will change the value of \f[B]seed\f[R]. This is a \f[B]non-portable extension\f[R]. .IP "21." 4 \f[B]irand(E)\f[R]: A pseudo-random integer between \f[B]0\f[R] (inclusive) and the value of \f[B]E\f[R] (exclusive). If \f[B]E\f[R] is negative or is a non-integer (\f[B]E\f[R]\[cq]s \f[I]scale\f[R] is not \f[B]0\f[R]), an error is raised, and bc(1) resets (see the \f[B]RESET\f[R] section) while \f[B]seed\f[R] remains unchanged. If \f[B]E\f[R] is larger than \f[B]BC_RAND_MAX\f[R], the higher bound is honored by generating several pseudo-random integers, multiplying them by appropriate powers of \f[B]BC_RAND_MAX+1\f[R], and adding them together. Thus, the size of integer that can be generated with this operand is unbounded. Using this operand will change the value of \f[B]seed\f[R], unless the value of \f[B]E\f[R] is \f[B]0\f[R] or \f[B]1\f[R]. In that case, \f[B]0\f[R] is returned, and \f[B]seed\f[R] is \f[I]not\f[R] changed. This is a \f[B]non-portable extension\f[R]. .IP "22." 4 \f[B]maxrand()\f[R]: The max integer returned by \f[B]rand()\f[R]. This is a \f[B]non-portable extension\f[R]. .PP The integers generated by \f[B]rand()\f[R] and \f[B]irand(E)\f[R] are guaranteed to be as unbiased as possible, subject to the limitations of the pseudo-random number generator. .PP \f[B]Note\f[R]: The values returned by the pseudo-random number generator with \f[B]rand()\f[R] and \f[B]irand(E)\f[R] are guaranteed to \f[I]NOT\f[R] be cryptographically secure. This is a consequence of using a seeded pseudo-random number generator. However, they \f[I]are\f[R] guaranteed to be reproducible with identical \f[B]seed\f[R] values. This means that the pseudo-random values from bc(1) should only be used where a reproducible stream of pseudo-random numbers is \f[I]ESSENTIAL\f[R]. In any other case, use a non-seeded pseudo-random number generator. .SS Numbers .PP Numbers are strings made up of digits, uppercase letters, and at most \f[B]1\f[R] period for a radix. Numbers can have up to \f[B]BC_NUM_MAX\f[R] digits. Uppercase letters are equal to \f[B]9\f[R] + their position in the alphabet (i.e., \f[B]A\f[R] equals \f[B]10\f[R], or \f[B]9+1\f[R]). If a digit or letter makes no sense with the current value of \f[B]ibase\f[R], they are set to the value of the highest valid digit in \f[B]ibase\f[R]. .PP Single-character numbers (i.e., \f[B]A\f[R] alone) take the value that they would have if they were valid digits, regardless of the value of \f[B]ibase\f[R]. This means that \f[B]A\f[R] alone always equals decimal \f[B]10\f[R] and \f[B]Z\f[R] alone always equals decimal \f[B]35\f[R]. .PP In addition, bc(1) accepts numbers in scientific notation. These have the form \f[B]e\f[R]. The exponent (the portion after the \f[B]e\f[R]) must be an integer. An example is \f[B]1.89237e9\f[R], which is equal to \f[B]1892370000\f[R]. Negative exponents are also allowed, so \f[B]4.2890e-3\f[R] is equal to \f[B]0.0042890\f[R]. .PP Using scientific notation is an error or warning if the \f[B]-s\f[R] or \f[B]-w\f[R], respectively, command-line options (or equivalents) are given. .PP \f[B]WARNING\f[R]: Both the number and the exponent in scientific notation are interpreted according to the current \f[B]ibase\f[R], but the number is still multiplied by \f[B]10\[ha]exponent\f[R] regardless of the current \f[B]ibase\f[R]. For example, if \f[B]ibase\f[R] is \f[B]16\f[R] and bc(1) is given the number string \f[B]FFeA\f[R], the resulting decimal number will be \f[B]2550000000000\f[R], and if bc(1) is given the number string \f[B]10e-4\f[R], the resulting decimal number will be \f[B]0.0016\f[R]. .PP Accepting input as scientific notation is a \f[B]non-portable extension\f[R]. .SS Operators .PP The following arithmetic and logical operators can be used. They are listed in order of decreasing precedence. Operators in the same group have the same precedence. .TP \f[B]++\f[R] \f[B]--\f[R] Type: Prefix and Postfix .RS .PP Associativity: None .PP Description: \f[B]increment\f[R], \f[B]decrement\f[R] .RE .TP \f[B]-\f[R] \f[B]!\f[R] Type: Prefix .RS .PP Associativity: None .PP Description: \f[B]negation\f[R], \f[B]boolean not\f[R] .RE .TP \f[B]$\f[R] Type: Postfix .RS .PP Associativity: None .PP Description: \f[B]truncation\f[R] .RE .TP \f[B]\[at]\f[R] Type: Binary .RS .PP Associativity: Right .PP Description: \f[B]set precision\f[R] .RE .TP \f[B]\[ha]\f[R] Type: Binary .RS .PP Associativity: Right .PP Description: \f[B]power\f[R] .RE .TP \f[B]*\f[R] \f[B]/\f[R] \f[B]%\f[R] Type: Binary .RS .PP Associativity: Left .PP Description: \f[B]multiply\f[R], \f[B]divide\f[R], \f[B]modulus\f[R] .RE .TP \f[B]+\f[R] \f[B]-\f[R] Type: Binary .RS .PP Associativity: Left .PP Description: \f[B]add\f[R], \f[B]subtract\f[R] .RE .TP \f[B]<<\f[R] \f[B]>>\f[R] Type: Binary .RS .PP Associativity: Left .PP Description: \f[B]shift left\f[R], \f[B]shift right\f[R] .RE .TP \f[B]=\f[R] \f[B]<<=\f[R] \f[B]>>=\f[R] \f[B]+=\f[R] \f[B]-=\f[R] \f[B]*=\f[R] \f[B]/=\f[R] \f[B]%=\f[R] \f[B]\[ha]=\f[R] \f[B]\[at]=\f[R] Type: Binary .RS .PP Associativity: Right .PP Description: \f[B]assignment\f[R] .RE .TP \f[B]==\f[R] \f[B]<=\f[R] \f[B]>=\f[R] \f[B]!=\f[R] \f[B]<\f[R] \f[B]>\f[R] Type: Binary .RS .PP Associativity: Left .PP Description: \f[B]relational\f[R] .RE .TP \f[B]&&\f[R] Type: Binary .RS .PP Associativity: Left .PP Description: \f[B]boolean and\f[R] .RE .TP \f[B]||\f[R] Type: Binary .RS .PP Associativity: Left .PP Description: \f[B]boolean or\f[R] .RE .PP The operators will be described in more detail below. .TP \f[B]++\f[R] \f[B]--\f[R] The prefix and postfix \f[B]increment\f[R] and \f[B]decrement\f[R] operators behave exactly like they would in C. They require a named expression (see the \f[I]Named Expressions\f[R] subsection) as an operand. .RS .PP The prefix versions of these operators are more efficient; use them where possible. .RE .TP \f[B]-\f[R] The \f[B]negation\f[R] operator returns \f[B]0\f[R] if a user attempts to negate any expression with the value \f[B]0\f[R]. Otherwise, a copy of the expression with its sign flipped is returned. .TP \f[B]!\f[R] The \f[B]boolean not\f[R] operator returns \f[B]1\f[R] if the expression is \f[B]0\f[R], or \f[B]0\f[R] otherwise. .RS .PP This is a \f[B]non-portable extension\f[R]. .RE .TP \f[B]$\f[R] The \f[B]truncation\f[R] operator returns a copy of the given expression with all of its \f[I]scale\f[R] removed. .RS .PP This is a \f[B]non-portable extension\f[R]. .RE .TP \f[B]\[at]\f[R] The \f[B]set precision\f[R] operator takes two expressions and returns a copy of the first with its \f[I]scale\f[R] equal to the value of the second expression. That could either mean that the number is returned without change (if the \f[I]scale\f[R] of the first expression matches the value of the second expression), extended (if it is less), or truncated (if it is more). .RS .PP The second expression must be an integer (no \f[I]scale\f[R]) and non-negative. .PP This is a \f[B]non-portable extension\f[R]. .RE .TP \f[B]\[ha]\f[R] The \f[B]power\f[R] operator (not the \f[B]exclusive or\f[R] operator, as it would be in C) takes two expressions and raises the first to the power of the value of the second. The \f[I]scale\f[R] of the result is equal to \f[B]scale\f[R]. .RS .PP The second expression must be an integer (no \f[I]scale\f[R]), and if it is negative, the first value must be non-zero. .RE .TP \f[B]*\f[R] The \f[B]multiply\f[R] operator takes two expressions, multiplies them, and returns the product. If \f[B]a\f[R] is the \f[I]scale\f[R] of the first expression and \f[B]b\f[R] is the \f[I]scale\f[R] of the second expression, the \f[I]scale\f[R] of the result is equal to \f[B]min(a+b,max(scale,a,b))\f[R] where \f[B]min()\f[R] and \f[B]max()\f[R] return the obvious values. .TP \f[B]/\f[R] The \f[B]divide\f[R] operator takes two expressions, divides them, and returns the quotient. The \f[I]scale\f[R] of the result shall be the value of \f[B]scale\f[R]. .RS .PP The second expression must be non-zero. .RE .TP \f[B]%\f[R] The \f[B]modulus\f[R] operator takes two expressions, \f[B]a\f[R] and \f[B]b\f[R], and evaluates them by 1) Computing \f[B]a/b\f[R] to current \f[B]scale\f[R] and 2) Using the result of step 1 to calculate \f[B]a-(a/b)*b\f[R] to \f[I]scale\f[R] \f[B]max(scale+scale(b),scale(a))\f[R]. .RS .PP The second expression must be non-zero. .RE .TP \f[B]+\f[R] The \f[B]add\f[R] operator takes two expressions, \f[B]a\f[R] and \f[B]b\f[R], and returns the sum, with a \f[I]scale\f[R] equal to the max of the \f[I]scale\f[R]s of \f[B]a\f[R] and \f[B]b\f[R]. .TP \f[B]-\f[R] The \f[B]subtract\f[R] operator takes two expressions, \f[B]a\f[R] and \f[B]b\f[R], and returns the difference, with a \f[I]scale\f[R] equal to the max of the \f[I]scale\f[R]s of \f[B]a\f[R] and \f[B]b\f[R]. .TP \f[B]<<\f[R] The \f[B]left shift\f[R] operator takes two expressions, \f[B]a\f[R] and \f[B]b\f[R], and returns a copy of the value of \f[B]a\f[R] with its decimal point moved \f[B]b\f[R] places to the right. .RS .PP The second expression must be an integer (no \f[I]scale\f[R]) and non-negative. .PP This is a \f[B]non-portable extension\f[R]. .RE .TP \f[B]>>\f[R] The \f[B]right shift\f[R] operator takes two expressions, \f[B]a\f[R] and \f[B]b\f[R], and returns a copy of the value of \f[B]a\f[R] with its decimal point moved \f[B]b\f[R] places to the left. .RS .PP The second expression must be an integer (no \f[I]scale\f[R]) and non-negative. .PP This is a \f[B]non-portable extension\f[R]. .RE .TP \f[B]=\f[R] \f[B]<<=\f[R] \f[B]>>=\f[R] \f[B]+=\f[R] \f[B]-=\f[R] \f[B]*=\f[R] \f[B]/=\f[R] \f[B]%=\f[R] \f[B]\[ha]=\f[R] \f[B]\[at]=\f[R] The \f[B]assignment\f[R] operators take two expressions, \f[B]a\f[R] and \f[B]b\f[R] where \f[B]a\f[R] is a named expression (see the \f[I]Named Expressions\f[R] subsection). .RS .PP For \f[B]=\f[R], \f[B]b\f[R] is copied and the result is assigned to \f[B]a\f[R]. For all others, \f[B]a\f[R] and \f[B]b\f[R] are applied as operands to the corresponding arithmetic operator and the result is assigned to \f[B]a\f[R]. .PP The \f[B]assignment\f[R] operators that correspond to operators that are extensions are themselves \f[B]non-portable extensions\f[R]. .RE .TP \f[B]==\f[R] \f[B]<=\f[R] \f[B]>=\f[R] \f[B]!=\f[R] \f[B]<\f[R] \f[B]>\f[R] The \f[B]relational\f[R] operators compare two expressions, \f[B]a\f[R] and \f[B]b\f[R], and if the relation holds, according to C language semantics, the result is \f[B]1\f[R]. Otherwise, it is \f[B]0\f[R]. .RS .PP Note that unlike in C, these operators have a lower precedence than the \f[B]assignment\f[R] operators, which means that \f[B]a=b>c\f[R] is interpreted as \f[B](a=b)>c\f[R]. .PP Also, unlike the standard (https://pubs.opengroup.org/onlinepubs/9699919799/utilities/bc.html) requires, these operators can appear anywhere any other expressions can be used. This allowance is a \f[B]non-portable extension\f[R]. .RE .TP \f[B]&&\f[R] The \f[B]boolean and\f[R] operator takes two expressions and returns \f[B]1\f[R] if both expressions are non-zero, \f[B]0\f[R] otherwise. .RS .PP This is \f[I]not\f[R] a short-circuit operator. .PP This is a \f[B]non-portable extension\f[R]. .RE .TP \f[B]||\f[R] The \f[B]boolean or\f[R] operator takes two expressions and returns \f[B]1\f[R] if one of the expressions is non-zero, \f[B]0\f[R] otherwise. .RS .PP This is \f[I]not\f[R] a short-circuit operator. .PP This is a \f[B]non-portable extension\f[R]. .RE .SS Statements .PP The following items are statements: .IP " 1." 4 \f[B]E\f[R] .IP " 2." 4 \f[B]{\f[R] \f[B]S\f[R] \f[B];\f[R] \&... \f[B];\f[R] \f[B]S\f[R] \f[B]}\f[R] .IP " 3." 4 \f[B]if\f[R] \f[B](\f[R] \f[B]E\f[R] \f[B])\f[R] \f[B]S\f[R] .IP " 4." 4 \f[B]if\f[R] \f[B](\f[R] \f[B]E\f[R] \f[B])\f[R] \f[B]S\f[R] \f[B]else\f[R] \f[B]S\f[R] .IP " 5." 4 \f[B]while\f[R] \f[B](\f[R] \f[B]E\f[R] \f[B])\f[R] \f[B]S\f[R] .IP " 6." 4 \f[B]for\f[R] \f[B](\f[R] \f[B]E\f[R] \f[B];\f[R] \f[B]E\f[R] \f[B];\f[R] \f[B]E\f[R] \f[B])\f[R] \f[B]S\f[R] .IP " 7." 4 An empty statement .IP " 8." 4 \f[B]break\f[R] .IP " 9." 4 \f[B]continue\f[R] .IP "10." 4 \f[B]quit\f[R] .IP "11." 4 \f[B]halt\f[R] .IP "12." 4 \f[B]limits\f[R] .IP "13." 4 A string of characters, enclosed in double quotes .IP "14." 4 \f[B]print\f[R] \f[B]E\f[R] \f[B],\f[R] \&... \f[B],\f[R] \f[B]E\f[R] .IP "15." 4 \f[B]stream\f[R] \f[B]E\f[R] \f[B],\f[R] \&... \f[B],\f[R] \f[B]E\f[R] .IP "16." 4 \f[B]I()\f[R], \f[B]I(E)\f[R], \f[B]I(E, E)\f[R], and so on, where \f[B]I\f[R] is an identifier for a \f[B]void\f[R] function (see the \f[I]Void Functions\f[R] subsection of the \f[B]FUNCTIONS\f[R] section). The \f[B]E\f[R] argument(s) may also be arrays of the form \f[B]I[]\f[R], which will automatically be turned into array references (see the \f[I]Array References\f[R] subsection of the \f[B]FUNCTIONS\f[R] section) if the corresponding parameter in the function definition is an array reference. .PP Numbers 4, 9, 11, 12, 14, 15, and 16 are \f[B]non-portable extensions\f[R]. .PP Also, as a \f[B]non-portable extension\f[R], any or all of the expressions in the header of a for loop may be omitted. If the condition (second expression) is omitted, it is assumed to be a constant \f[B]1\f[R]. .PP The \f[B]break\f[R] statement causes a loop to stop iterating and resume execution immediately following a loop. This is only allowed in loops. .PP The \f[B]continue\f[R] statement causes a loop iteration to stop early and returns to the start of the loop, including testing the loop condition. This is only allowed in loops. .PP The \f[B]if\f[R] \f[B]else\f[R] statement does the same thing as in C. .PP The \f[B]quit\f[R] statement causes bc(1) to quit, even if it is on a branch that will not be executed (it is a compile-time command). .PP The \f[B]halt\f[R] statement causes bc(1) to quit, if it is executed. (Unlike \f[B]quit\f[R] if it is on a branch of an \f[B]if\f[R] statement that is not executed, bc(1) does not quit.) .PP The \f[B]limits\f[R] statement prints the limits that this bc(1) is subject to. This is like the \f[B]quit\f[R] statement in that it is a compile-time command. .PP An expression by itself is evaluated and printed, followed by a newline. .PP Both scientific notation and engineering notation are available for printing the results of expressions. Scientific notation is activated by assigning \f[B]0\f[R] to \f[B]obase\f[R], and engineering notation is activated by assigning \f[B]1\f[R] to \f[B]obase\f[R]. To deactivate them, just assign a different value to \f[B]obase\f[R]. .PP Scientific notation and engineering notation are disabled if bc(1) is run with either the \f[B]-s\f[R] or \f[B]-w\f[R] command-line options (or equivalents). .PP Printing numbers in scientific notation and/or engineering notation is a \f[B]non-portable extension\f[R]. .SS Strings .PP If strings appear as a statement by themselves, they are printed without a trailing newline. .PP In addition to appearing as a lone statement by themselves, strings can be assigned to variables and array elements. They can also be passed to functions in variable parameters. .PP If any statement that expects a string is given a variable that had a string assigned to it, the statement acts as though it had received a string. .PP If any math operation is attempted on a string or a variable or array element that has been assigned a string, an error is raised, and bc(1) resets (see the \f[B]RESET\f[R] section). .PP Assigning strings to variables and array elements and passing them to functions are \f[B]non-portable extensions\f[R]. .SS Print Statement .PP The \[lq]expressions\[rq] in a \f[B]print\f[R] statement may also be strings. If they are, there are backslash escape sequences that are interpreted specially. What those sequences are, and what they cause to be printed, are shown below: .PP \f[B]\[rs]a\f[R]: \f[B]\[rs]a\f[R] .PP \f[B]\[rs]b\f[R]: \f[B]\[rs]b\f[R] .PP \f[B]\[rs]\[rs]\f[R]: \f[B]\[rs]\f[R] .PP \f[B]\[rs]e\f[R]: \f[B]\[rs]\f[R] .PP \f[B]\[rs]f\f[R]: \f[B]\[rs]f\f[R] .PP \f[B]\[rs]n\f[R]: \f[B]\[rs]n\f[R] .PP \f[B]\[rs]q\f[R]: \f[B]\[lq]\f[R] .PP \f[B]\[rs]r\f[R]: \f[B]\[rs]r\f[R] .PP \f[B]\[rs]t\f[R]: \f[B]\[rs]t\f[R] .PP Any other character following a backslash causes the backslash and character to be printed as-is. .PP Any non-string expression in a print statement shall be assigned to \f[B]last\f[R], like any other expression that is printed. .SS Stream Statement .PP The \[lq]expressions in a \f[B]stream\f[R] statement may also be strings. .PP If a \f[B]stream\f[R] statement is given a string, it prints the string as though the string had appeared as its own statement. In other words, the \f[B]stream\f[R] statement prints strings normally, without a newline. .PP If a \f[B]stream\f[R] statement is given a number, a copy of it is truncated and its absolute value is calculated. The result is then printed as though \f[B]obase\f[R] is \f[B]256\f[R] and each digit is interpreted as an 8-bit ASCII character, making it a byte stream. .SS Order of Evaluation .PP All expressions in a statment are evaluated left to right, except as necessary to maintain order of operations. This means, for example, assuming that \f[B]i\f[R] is equal to \f[B]0\f[R], in the expression .IP .nf \f[C] a[i++] = i++ \f[R] .fi .PP the first (or 0th) element of \f[B]a\f[R] is set to \f[B]1\f[R], and \f[B]i\f[R] is equal to \f[B]2\f[R] at the end of the expression. .PP This includes function arguments. Thus, assuming \f[B]i\f[R] is equal to \f[B]0\f[R], this means that in the expression .IP .nf \f[C] x(i++, i++) \f[R] .fi .PP the first argument passed to \f[B]x()\f[R] is \f[B]0\f[R], and the second argument is \f[B]1\f[R], while \f[B]i\f[R] is equal to \f[B]2\f[R] before the function starts executing. .SH FUNCTIONS .PP Function definitions are as follows: .IP .nf \f[C] define I(I,...,I){ auto I,...,I S;...;S return(E) } \f[R] .fi .PP Any \f[B]I\f[R] in the parameter list or \f[B]auto\f[R] list may be replaced with \f[B]I[]\f[R] to make a parameter or \f[B]auto\f[R] var an array, and any \f[B]I\f[R] in the parameter list may be replaced with \f[B]*I[]\f[R] to make a parameter an array reference. Callers of functions that take array references should not put an asterisk in the call; they must be called with just \f[B]I[]\f[R] like normal array parameters and will be automatically converted into references. .PP As a \f[B]non-portable extension\f[R], the opening brace of a \f[B]define\f[R] statement may appear on the next line. .PP As a \f[B]non-portable extension\f[R], the return statement may also be in one of the following forms: .IP "1." 3 \f[B]return\f[R] .IP "2." 3 \f[B]return\f[R] \f[B](\f[R] \f[B])\f[R] .IP "3." 3 \f[B]return\f[R] \f[B]E\f[R] .PP The first two, or not specifying a \f[B]return\f[R] statement, is equivalent to \f[B]return (0)\f[R], unless the function is a \f[B]void\f[R] function (see the \f[I]Void Functions\f[R] subsection below). .SS Void Functions .PP Functions can also be \f[B]void\f[R] functions, defined as follows: .IP .nf \f[C] define void I(I,...,I){ auto I,...,I S;...;S return } \f[R] .fi .PP They can only be used as standalone expressions, where such an expression would be printed alone, except in a print statement. .PP Void functions can only use the first two \f[B]return\f[R] statements listed above. They can also omit the return statement entirely. .PP The word \[lq]void\[rq] is not treated as a keyword; it is still possible to have variables, arrays, and functions named \f[B]void\f[R]. The word \[lq]void\[rq] is only treated specially right after the \f[B]define\f[R] keyword. .PP This is a \f[B]non-portable extension\f[R]. .SS Array References .PP For any array in the parameter list, if the array is declared in the form .IP .nf \f[C] *I[] \f[R] .fi .PP it is a \f[B]reference\f[R]. Any changes to the array in the function are reflected, when the function returns, to the array that was passed in. .PP Other than this, all function arguments are passed by value. .PP This is a \f[B]non-portable extension\f[R]. .SH LIBRARY .PP All of the functions below, including the functions in the extended math library (see the \f[I]Extended Library\f[R] subsection below), are available when the \f[B]-l\f[R] or \f[B]--mathlib\f[R] command-line flags are given, except that the extended math library is not available when the \f[B]-s\f[R] option, the \f[B]-w\f[R] option, or equivalents are given. .SS Standard Library .PP The standard (https://pubs.opengroup.org/onlinepubs/9699919799/utilities/bc.html) defines the following functions for the math library: .TP \f[B]s(x)\f[R] Returns the sine of \f[B]x\f[R], which is assumed to be in radians. .RS .PP This is a transcendental function (see the \f[I]Transcendental Functions\f[R] subsection below). .RE .TP \f[B]c(x)\f[R] Returns the cosine of \f[B]x\f[R], which is assumed to be in radians. .RS .PP This is a transcendental function (see the \f[I]Transcendental Functions\f[R] subsection below). .RE .TP \f[B]a(x)\f[R] Returns the arctangent of \f[B]x\f[R], in radians. .RS .PP This is a transcendental function (see the \f[I]Transcendental Functions\f[R] subsection below). .RE .TP \f[B]l(x)\f[R] Returns the natural logarithm of \f[B]x\f[R]. .RS .PP This is a transcendental function (see the \f[I]Transcendental Functions\f[R] subsection below). .RE .TP \f[B]e(x)\f[R] Returns the mathematical constant \f[B]e\f[R] raised to the power of \f[B]x\f[R]. .RS .PP This is a transcendental function (see the \f[I]Transcendental Functions\f[R] subsection below). .RE .TP \f[B]j(x, n)\f[R] Returns the bessel integer order \f[B]n\f[R] (truncated) of \f[B]x\f[R]. .RS .PP This is a transcendental function (see the \f[I]Transcendental Functions\f[R] subsection below). .RE .SS Extended Library .PP The extended library is \f[I]not\f[R] loaded when the \f[B]-s\f[R]/\f[B]--standard\f[R] or \f[B]-w\f[R]/\f[B]--warn\f[R] options are given since they are not part of the library defined by the standard (https://pubs.opengroup.org/onlinepubs/9699919799/utilities/bc.html). .PP The extended library is a \f[B]non-portable extension\f[R]. .TP \f[B]p(x, y)\f[R] Calculates \f[B]x\f[R] to the power of \f[B]y\f[R], even if \f[B]y\f[R] is not an integer, and returns the result to the current \f[B]scale\f[R]. .RS .PP It is an error if \f[B]y\f[R] is negative and \f[B]x\f[R] is \f[B]0\f[R]. .PP This is a transcendental function (see the \f[I]Transcendental Functions\f[R] subsection below). .RE .TP \f[B]r(x, p)\f[R] Returns \f[B]x\f[R] rounded to \f[B]p\f[R] decimal places according to the rounding mode round half away from \f[B]0\f[R] (https://en.wikipedia.org/wiki/Rounding#Round_half_away_from_zero). .TP \f[B]ceil(x, p)\f[R] Returns \f[B]x\f[R] rounded to \f[B]p\f[R] decimal places according to the rounding mode round away from \f[B]0\f[R] (https://en.wikipedia.org/wiki/Rounding#Rounding_away_from_zero). .TP \f[B]f(x)\f[R] Returns the factorial of the truncated absolute value of \f[B]x\f[R]. .TP \f[B]perm(n, k)\f[R] Returns the permutation of the truncated absolute value of \f[B]n\f[R] of the truncated absolute value of \f[B]k\f[R], if \f[B]k <= n\f[R]. If not, it returns \f[B]0\f[R]. .TP \f[B]comb(n, k)\f[R] Returns the combination of the truncated absolute value of \f[B]n\f[R] of the truncated absolute value of \f[B]k\f[R], if \f[B]k <= n\f[R]. If not, it returns \f[B]0\f[R]. .TP \f[B]l2(x)\f[R] Returns the logarithm base \f[B]2\f[R] of \f[B]x\f[R]. .RS .PP This is a transcendental function (see the \f[I]Transcendental Functions\f[R] subsection below). .RE .TP \f[B]l10(x)\f[R] Returns the logarithm base \f[B]10\f[R] of \f[B]x\f[R]. .RS .PP This is a transcendental function (see the \f[I]Transcendental Functions\f[R] subsection below). .RE .TP \f[B]log(x, b)\f[R] Returns the logarithm base \f[B]b\f[R] of \f[B]x\f[R]. .RS .PP This is a transcendental function (see the \f[I]Transcendental Functions\f[R] subsection below). .RE .TP \f[B]cbrt(x)\f[R] Returns the cube root of \f[B]x\f[R]. .TP \f[B]root(x, n)\f[R] Calculates the truncated value of \f[B]n\f[R], \f[B]r\f[R], and returns the \f[B]r\f[R]th root of \f[B]x\f[R] to the current \f[B]scale\f[R]. .RS .PP If \f[B]r\f[R] is \f[B]0\f[R] or negative, this raises an error and causes bc(1) to reset (see the \f[B]RESET\f[R] section). It also raises an error and causes bc(1) to reset if \f[B]r\f[R] is even and \f[B]x\f[R] is negative. .RE .TP \f[B]gcd(a, b)\f[R] Returns the greatest common divisor (factor) of the truncated absolute value of \f[B]a\f[R] and the truncated absolute value of \f[B]b\f[R]. .TP \f[B]lcm(a, b)\f[R] Returns the least common multiple of the truncated absolute value of \f[B]a\f[R] and the truncated absolute value of \f[B]b\f[R]. .TP \f[B]pi(p)\f[R] Returns \f[B]pi\f[R] to \f[B]p\f[R] decimal places. .RS .PP This is a transcendental function (see the \f[I]Transcendental Functions\f[R] subsection below). .RE .TP \f[B]t(x)\f[R] Returns the tangent of \f[B]x\f[R], which is assumed to be in radians. .RS .PP This is a transcendental function (see the \f[I]Transcendental Functions\f[R] subsection below). .RE .TP \f[B]a2(y, x)\f[R] Returns the arctangent of \f[B]y/x\f[R], in radians. If both \f[B]y\f[R] and \f[B]x\f[R] are equal to \f[B]0\f[R], it raises an error and causes bc(1) to reset (see the \f[B]RESET\f[R] section). Otherwise, if \f[B]x\f[R] is greater than \f[B]0\f[R], it returns \f[B]a(y/x)\f[R]. If \f[B]x\f[R] is less than \f[B]0\f[R], and \f[B]y\f[R] is greater than or equal to \f[B]0\f[R], it returns \f[B]a(y/x)+pi\f[R]. If \f[B]x\f[R] is less than \f[B]0\f[R], and \f[B]y\f[R] is less than \f[B]0\f[R], it returns \f[B]a(y/x)-pi\f[R]. If \f[B]x\f[R] is equal to \f[B]0\f[R], and \f[B]y\f[R] is greater than \f[B]0\f[R], it returns \f[B]pi/2\f[R]. If \f[B]x\f[R] is equal to \f[B]0\f[R], and \f[B]y\f[R] is less than \f[B]0\f[R], it returns \f[B]-pi/2\f[R]. .RS .PP This function is the same as the \f[B]atan2()\f[R] function in many programming languages. .PP This is a transcendental function (see the \f[I]Transcendental Functions\f[R] subsection below). .RE .TP \f[B]sin(x)\f[R] Returns the sine of \f[B]x\f[R], which is assumed to be in radians. .RS .PP This is an alias of \f[B]s(x)\f[R]. .PP This is a transcendental function (see the \f[I]Transcendental Functions\f[R] subsection below). .RE .TP \f[B]cos(x)\f[R] Returns the cosine of \f[B]x\f[R], which is assumed to be in radians. .RS .PP This is an alias of \f[B]c(x)\f[R]. .PP This is a transcendental function (see the \f[I]Transcendental Functions\f[R] subsection below). .RE .TP \f[B]tan(x)\f[R] Returns the tangent of \f[B]x\f[R], which is assumed to be in radians. .RS .PP If \f[B]x\f[R] is equal to \f[B]1\f[R] or \f[B]-1\f[R], this raises an error and causes bc(1) to reset (see the \f[B]RESET\f[R] section). .PP This is an alias of \f[B]t(x)\f[R]. .PP This is a transcendental function (see the \f[I]Transcendental Functions\f[R] subsection below). .RE .TP \f[B]atan(x)\f[R] Returns the arctangent of \f[B]x\f[R], in radians. .RS .PP This is an alias of \f[B]a(x)\f[R]. .PP This is a transcendental function (see the \f[I]Transcendental Functions\f[R] subsection below). .RE .TP \f[B]atan2(y, x)\f[R] Returns the arctangent of \f[B]y/x\f[R], in radians. If both \f[B]y\f[R] and \f[B]x\f[R] are equal to \f[B]0\f[R], it raises an error and causes bc(1) to reset (see the \f[B]RESET\f[R] section). Otherwise, if \f[B]x\f[R] is greater than \f[B]0\f[R], it returns \f[B]a(y/x)\f[R]. If \f[B]x\f[R] is less than \f[B]0\f[R], and \f[B]y\f[R] is greater than or equal to \f[B]0\f[R], it returns \f[B]a(y/x)+pi\f[R]. If \f[B]x\f[R] is less than \f[B]0\f[R], and \f[B]y\f[R] is less than \f[B]0\f[R], it returns \f[B]a(y/x)-pi\f[R]. If \f[B]x\f[R] is equal to \f[B]0\f[R], and \f[B]y\f[R] is greater than \f[B]0\f[R], it returns \f[B]pi/2\f[R]. If \f[B]x\f[R] is equal to \f[B]0\f[R], and \f[B]y\f[R] is less than \f[B]0\f[R], it returns \f[B]-pi/2\f[R]. .RS .PP This function is the same as the \f[B]atan2()\f[R] function in many programming languages. .PP This is an alias of \f[B]a2(y, x)\f[R]. .PP This is a transcendental function (see the \f[I]Transcendental Functions\f[R] subsection below). .RE .TP \f[B]r2d(x)\f[R] Converts \f[B]x\f[R] from radians to degrees and returns the result. .RS .PP This is a transcendental function (see the \f[I]Transcendental Functions\f[R] subsection below). .RE .TP \f[B]d2r(x)\f[R] Converts \f[B]x\f[R] from degrees to radians and returns the result. .RS .PP This is a transcendental function (see the \f[I]Transcendental Functions\f[R] subsection below). .RE .TP \f[B]frand(p)\f[R] Generates a pseudo-random number between \f[B]0\f[R] (inclusive) and \f[B]1\f[R] (exclusive) with the number of decimal digits after the decimal point equal to the truncated absolute value of \f[B]p\f[R]. If \f[B]p\f[R] is not \f[B]0\f[R], then calling this function will change the value of \f[B]seed\f[R]. If \f[B]p\f[R] is \f[B]0\f[R], then \f[B]0\f[R] is returned, and \f[B]seed\f[R] is \f[I]not\f[R] changed. .TP \f[B]ifrand(i, p)\f[R] Generates a pseudo-random number that is between \f[B]0\f[R] (inclusive) and the truncated absolute value of \f[B]i\f[R] (exclusive) with the number of decimal digits after the decimal point equal to the truncated absolute value of \f[B]p\f[R]. If the absolute value of \f[B]i\f[R] is greater than or equal to \f[B]2\f[R], and \f[B]p\f[R] is not \f[B]0\f[R], then calling this function will change the value of \f[B]seed\f[R]; otherwise, \f[B]0\f[R] is returned and \f[B]seed\f[R] is not changed. .TP \f[B]srand(x)\f[R] Returns \f[B]x\f[R] with its sign flipped with probability \f[B]0.5\f[R]. In other words, it randomizes the sign of \f[B]x\f[R]. .TP \f[B]brand()\f[R] Returns a random boolean value (either \f[B]0\f[R] or \f[B]1\f[R]). .TP \f[B]band(a, b)\f[R] Takes the truncated absolute value of both \f[B]a\f[R] and \f[B]b\f[R] and calculates and returns the result of the bitwise \f[B]and\f[R] operation between them. .RS .PP If you want to use signed two\[cq]s complement arguments, use \f[B]s2u(x)\f[R] to convert. .RE .TP \f[B]bor(a, b)\f[R] Takes the truncated absolute value of both \f[B]a\f[R] and \f[B]b\f[R] and calculates and returns the result of the bitwise \f[B]or\f[R] operation between them. .RS .PP If you want to use signed two\[cq]s complement arguments, use \f[B]s2u(x)\f[R] to convert. .RE .TP \f[B]bxor(a, b)\f[R] Takes the truncated absolute value of both \f[B]a\f[R] and \f[B]b\f[R] and calculates and returns the result of the bitwise \f[B]xor\f[R] operation between them. .RS .PP If you want to use signed two\[cq]s complement arguments, use \f[B]s2u(x)\f[R] to convert. .RE .TP \f[B]bshl(a, b)\f[R] Takes the truncated absolute value of both \f[B]a\f[R] and \f[B]b\f[R] and calculates and returns the result of \f[B]a\f[R] bit-shifted left by \f[B]b\f[R] places. .RS .PP If you want to use signed two\[cq]s complement arguments, use \f[B]s2u(x)\f[R] to convert. .RE .TP \f[B]bshr(a, b)\f[R] Takes the truncated absolute value of both \f[B]a\f[R] and \f[B]b\f[R] and calculates and returns the truncated result of \f[B]a\f[R] bit-shifted right by \f[B]b\f[R] places. .RS .PP If you want to use signed two\[cq]s complement arguments, use \f[B]s2u(x)\f[R] to convert. .RE .TP \f[B]bnotn(x, n)\f[R] Takes the truncated absolute value of \f[B]x\f[R] and does a bitwise not as though it has the same number of bytes as the truncated absolute value of \f[B]n\f[R]. .RS .PP If you want to a use signed two\[cq]s complement argument, use \f[B]s2u(x)\f[R] to convert. .RE .TP \f[B]bnot8(x)\f[R] Does a bitwise not of the truncated absolute value of \f[B]x\f[R] as though it has \f[B]8\f[R] binary digits (1 unsigned byte). .RS .PP If you want to a use signed two\[cq]s complement argument, use \f[B]s2u(x)\f[R] to convert. .RE .TP \f[B]bnot16(x)\f[R] Does a bitwise not of the truncated absolute value of \f[B]x\f[R] as though it has \f[B]16\f[R] binary digits (2 unsigned bytes). .RS .PP If you want to a use signed two\[cq]s complement argument, use \f[B]s2u(x)\f[R] to convert. .RE .TP \f[B]bnot32(x)\f[R] Does a bitwise not of the truncated absolute value of \f[B]x\f[R] as though it has \f[B]32\f[R] binary digits (4 unsigned bytes). .RS .PP If you want to a use signed two\[cq]s complement argument, use \f[B]s2u(x)\f[R] to convert. .RE .TP \f[B]bnot64(x)\f[R] Does a bitwise not of the truncated absolute value of \f[B]x\f[R] as though it has \f[B]64\f[R] binary digits (8 unsigned bytes). .RS .PP If you want to a use signed two\[cq]s complement argument, use \f[B]s2u(x)\f[R] to convert. .RE .TP \f[B]bnot(x)\f[R] Does a bitwise not of the truncated absolute value of \f[B]x\f[R] as though it has the minimum number of power of two unsigned bytes. .RS .PP If you want to a use signed two\[cq]s complement argument, use \f[B]s2u(x)\f[R] to convert. .RE .TP \f[B]brevn(x, n)\f[R] Runs a bit reversal on the truncated absolute value of \f[B]x\f[R] as though it has the same number of 8-bit bytes as the truncated absolute value of \f[B]n\f[R]. .RS .PP If you want to a use signed two\[cq]s complement argument, use \f[B]s2u(x)\f[R] to convert. .RE .TP \f[B]brev8(x)\f[R] Runs a bit reversal on the truncated absolute value of \f[B]x\f[R] as though it has 8 binary digits (1 unsigned byte). .RS .PP If you want to a use signed two\[cq]s complement argument, use \f[B]s2u(x)\f[R] to convert. .RE .TP \f[B]brev16(x)\f[R] Runs a bit reversal on the truncated absolute value of \f[B]x\f[R] as though it has 16 binary digits (2 unsigned bytes). .RS .PP If you want to a use signed two\[cq]s complement argument, use \f[B]s2u(x)\f[R] to convert. .RE .TP \f[B]brev32(x)\f[R] Runs a bit reversal on the truncated absolute value of \f[B]x\f[R] as though it has 32 binary digits (4 unsigned bytes). .RS .PP If you want to a use signed two\[cq]s complement argument, use \f[B]s2u(x)\f[R] to convert. .RE .TP \f[B]brev64(x)\f[R] Runs a bit reversal on the truncated absolute value of \f[B]x\f[R] as though it has 64 binary digits (8 unsigned bytes). .RS .PP If you want to a use signed two\[cq]s complement argument, use \f[B]s2u(x)\f[R] to convert. .RE .TP \f[B]brev(x)\f[R] Runs a bit reversal on the truncated absolute value of \f[B]x\f[R] as though it has the minimum number of power of two unsigned bytes. .RS .PP If you want to a use signed two\[cq]s complement argument, use \f[B]s2u(x)\f[R] to convert. .RE .TP \f[B]broln(x, p, n)\f[R] Does a left bitwise rotatation of the truncated absolute value of \f[B]x\f[R], as though it has the same number of unsigned 8-bit bytes as the truncated absolute value of \f[B]n\f[R], by the number of places equal to the truncated absolute value of \f[B]p\f[R] modded by the \f[B]2\f[R] to the power of the number of binary digits in \f[B]n\f[R] 8-bit bytes. .RS .PP If you want to a use signed two\[cq]s complement argument, use \f[B]s2u(x)\f[R] to convert. .RE .TP \f[B]brol8(x, p)\f[R] Does a left bitwise rotatation of the truncated absolute value of \f[B]x\f[R], as though it has \f[B]8\f[R] binary digits (\f[B]1\f[R] unsigned byte), by the number of places equal to the truncated absolute value of \f[B]p\f[R] modded by \f[B]2\f[R] to the power of \f[B]8\f[R]. .RS .PP If you want to a use signed two\[cq]s complement argument, use \f[B]s2u(x)\f[R] to convert. .RE .TP \f[B]brol16(x, p)\f[R] Does a left bitwise rotatation of the truncated absolute value of \f[B]x\f[R], as though it has \f[B]16\f[R] binary digits (\f[B]2\f[R] unsigned bytes), by the number of places equal to the truncated absolute value of \f[B]p\f[R] modded by \f[B]2\f[R] to the power of \f[B]16\f[R]. .RS .PP If you want to a use signed two\[cq]s complement argument, use \f[B]s2u(x)\f[R] to convert. .RE .TP \f[B]brol32(x, p)\f[R] Does a left bitwise rotatation of the truncated absolute value of \f[B]x\f[R], as though it has \f[B]32\f[R] binary digits (\f[B]2\f[R] unsigned bytes), by the number of places equal to the truncated absolute value of \f[B]p\f[R] modded by \f[B]2\f[R] to the power of \f[B]32\f[R]. .RS .PP If you want to a use signed two\[cq]s complement argument, use \f[B]s2u(x)\f[R] to convert. .RE .TP \f[B]brol64(x, p)\f[R] Does a left bitwise rotatation of the truncated absolute value of \f[B]x\f[R], as though it has \f[B]64\f[R] binary digits (\f[B]2\f[R] unsigned bytes), by the number of places equal to the truncated absolute value of \f[B]p\f[R] modded by \f[B]2\f[R] to the power of \f[B]64\f[R]. .RS .PP If you want to a use signed two\[cq]s complement argument, use \f[B]s2u(x)\f[R] to convert. .RE .TP \f[B]brol(x, p)\f[R] Does a left bitwise rotatation of the truncated absolute value of \f[B]x\f[R], as though it has the minimum number of power of two unsigned 8-bit bytes, by the number of places equal to the truncated absolute value of \f[B]p\f[R] modded by 2 to the power of the number of binary digits in the minimum number of 8-bit bytes. .RS .PP If you want to a use signed two\[cq]s complement argument, use \f[B]s2u(x)\f[R] to convert. .RE .TP \f[B]brorn(x, p, n)\f[R] Does a right bitwise rotatation of the truncated absolute value of \f[B]x\f[R], as though it has the same number of unsigned 8-bit bytes as the truncated absolute value of \f[B]n\f[R], by the number of places equal to the truncated absolute value of \f[B]p\f[R] modded by the \f[B]2\f[R] to the power of the number of binary digits in \f[B]n\f[R] 8-bit bytes. .RS .PP If you want to a use signed two\[cq]s complement argument, use \f[B]s2u(x)\f[R] to convert. .RE .TP \f[B]bror8(x, p)\f[R] Does a right bitwise rotatation of the truncated absolute value of \f[B]x\f[R], as though it has \f[B]8\f[R] binary digits (\f[B]1\f[R] unsigned byte), by the number of places equal to the truncated absolute value of \f[B]p\f[R] modded by \f[B]2\f[R] to the power of \f[B]8\f[R]. .RS .PP If you want to a use signed two\[cq]s complement argument, use \f[B]s2u(x)\f[R] to convert. .RE .TP \f[B]bror16(x, p)\f[R] Does a right bitwise rotatation of the truncated absolute value of \f[B]x\f[R], as though it has \f[B]16\f[R] binary digits (\f[B]2\f[R] unsigned bytes), by the number of places equal to the truncated absolute value of \f[B]p\f[R] modded by \f[B]2\f[R] to the power of \f[B]16\f[R]. .RS .PP If you want to a use signed two\[cq]s complement argument, use \f[B]s2u(x)\f[R] to convert. .RE .TP \f[B]bror32(x, p)\f[R] Does a right bitwise rotatation of the truncated absolute value of \f[B]x\f[R], as though it has \f[B]32\f[R] binary digits (\f[B]2\f[R] unsigned bytes), by the number of places equal to the truncated absolute value of \f[B]p\f[R] modded by \f[B]2\f[R] to the power of \f[B]32\f[R]. .RS .PP If you want to a use signed two\[cq]s complement argument, use \f[B]s2u(x)\f[R] to convert. .RE .TP \f[B]bror64(x, p)\f[R] Does a right bitwise rotatation of the truncated absolute value of \f[B]x\f[R], as though it has \f[B]64\f[R] binary digits (\f[B]2\f[R] unsigned bytes), by the number of places equal to the truncated absolute value of \f[B]p\f[R] modded by \f[B]2\f[R] to the power of \f[B]64\f[R]. .RS .PP If you want to a use signed two\[cq]s complement argument, use \f[B]s2u(x)\f[R] to convert. .RE .TP \f[B]bror(x, p)\f[R] Does a right bitwise rotatation of the truncated absolute value of \f[B]x\f[R], as though it has the minimum number of power of two unsigned 8-bit bytes, by the number of places equal to the truncated absolute value of \f[B]p\f[R] modded by 2 to the power of the number of binary digits in the minimum number of 8-bit bytes. .RS .PP If you want to a use signed two\[cq]s complement argument, use \f[B]s2u(x)\f[R] to convert. .RE .TP \f[B]bmodn(x, n)\f[R] Returns the modulus of the truncated absolute value of \f[B]x\f[R] by \f[B]2\f[R] to the power of the multiplication of the truncated absolute value of \f[B]n\f[R] and \f[B]8\f[R]. .RS .PP If you want to a use signed two\[cq]s complement argument, use \f[B]s2u(x)\f[R] to convert. .RE .TP \f[B]bmod8(x, n)\f[R] Returns the modulus of the truncated absolute value of \f[B]x\f[R] by \f[B]2\f[R] to the power of \f[B]8\f[R]. .RS .PP If you want to a use signed two\[cq]s complement argument, use \f[B]s2u(x)\f[R] to convert. .RE .TP \f[B]bmod16(x, n)\f[R] Returns the modulus of the truncated absolute value of \f[B]x\f[R] by \f[B]2\f[R] to the power of \f[B]16\f[R]. .RS .PP If you want to a use signed two\[cq]s complement argument, use \f[B]s2u(x)\f[R] to convert. .RE .TP \f[B]bmod32(x, n)\f[R] Returns the modulus of the truncated absolute value of \f[B]x\f[R] by \f[B]2\f[R] to the power of \f[B]32\f[R]. .RS .PP If you want to a use signed two\[cq]s complement argument, use \f[B]s2u(x)\f[R] to convert. .RE .TP \f[B]bmod64(x, n)\f[R] Returns the modulus of the truncated absolute value of \f[B]x\f[R] by \f[B]2\f[R] to the power of \f[B]64\f[R]. .RS .PP If you want to a use signed two\[cq]s complement argument, use \f[B]s2u(x)\f[R] to convert. .RE .TP \f[B]bunrev(t)\f[R] Assumes \f[B]t\f[R] is a bitwise-reversed number with an extra set bit one place more significant than the real most significant bit (which was the least significant bit in the original number). This number is reversed and returned without the extra set bit. .RS .PP This function is used to implement other bitwise functions; it is not meant to be used by users, but it can be. .RE .TP \f[B]plz(x)\f[R] If \f[B]x\f[R] is not equal to \f[B]0\f[R] and greater that \f[B]-1\f[R] and less than \f[B]1\f[R], it is printed with a leading zero, regardless of the use of the \f[B]-z\f[R] option (see the \f[B]OPTIONS\f[R] section) and without a trailing newline. .RS .PP Otherwise, \f[B]x\f[R] is printed normally, without a trailing newline. .RE .TP \f[B]plznl(x)\f[R] If \f[B]x\f[R] is not equal to \f[B]0\f[R] and greater that \f[B]-1\f[R] and less than \f[B]1\f[R], it is printed with a leading zero, regardless of the use of the \f[B]-z\f[R] option (see the \f[B]OPTIONS\f[R] section) and with a trailing newline. .RS .PP Otherwise, \f[B]x\f[R] is printed normally, with a trailing newline. .RE .TP \f[B]pnlz(x)\f[R] If \f[B]x\f[R] is not equal to \f[B]0\f[R] and greater that \f[B]-1\f[R] and less than \f[B]1\f[R], it is printed without a leading zero, regardless of the use of the \f[B]-z\f[R] option (see the \f[B]OPTIONS\f[R] section) and without a trailing newline. .RS .PP Otherwise, \f[B]x\f[R] is printed normally, without a trailing newline. .RE .TP \f[B]pnlznl(x)\f[R] If \f[B]x\f[R] is not equal to \f[B]0\f[R] and greater that \f[B]-1\f[R] and less than \f[B]1\f[R], it is printed without a leading zero, regardless of the use of the \f[B]-z\f[R] option (see the \f[B]OPTIONS\f[R] section) and with a trailing newline. .RS .PP Otherwise, \f[B]x\f[R] is printed normally, with a trailing newline. .RE .TP \f[B]ubytes(x)\f[R] Returns the numbers of unsigned integer bytes required to hold the truncated absolute value of \f[B]x\f[R]. .TP \f[B]sbytes(x)\f[R] Returns the numbers of signed, two\[cq]s-complement integer bytes required to hold the truncated value of \f[B]x\f[R]. .TP \f[B]s2u(x)\f[R] Returns \f[B]x\f[R] if it is non-negative. If it \f[I]is\f[R] negative, then it calculates what \f[B]x\f[R] would be as a 2\[cq]s-complement signed integer and returns the non-negative integer that would have the same representation in binary. .TP \f[B]s2un(x,n)\f[R] Returns \f[B]x\f[R] if it is non-negative. If it \f[I]is\f[R] negative, then it calculates what \f[B]x\f[R] would be as a 2\[cq]s-complement signed integer with \f[B]n\f[R] bytes and returns the non-negative integer that would have the same representation in binary. If \f[B]x\f[R] cannot fit into \f[B]n\f[R] 2\[cq]s-complement signed bytes, it is truncated to fit. .TP \f[B]hex(x)\f[R] Outputs the hexadecimal (base \f[B]16\f[R]) representation of \f[B]x\f[R]. .RS .PP This is a \f[B]void\f[R] function (see the \f[I]Void Functions\f[R] subsection of the \f[B]FUNCTIONS\f[R] section). .RE .TP \f[B]binary(x)\f[R] Outputs the binary (base \f[B]2\f[R]) representation of \f[B]x\f[R]. .RS .PP This is a \f[B]void\f[R] function (see the \f[I]Void Functions\f[R] subsection of the \f[B]FUNCTIONS\f[R] section). .RE .TP \f[B]output(x, b)\f[R] Outputs the base \f[B]b\f[R] representation of \f[B]x\f[R]. .RS .PP This is a \f[B]void\f[R] function (see the \f[I]Void Functions\f[R] subsection of the \f[B]FUNCTIONS\f[R] section). .RE .TP \f[B]uint(x)\f[R] Outputs the representation, in binary and hexadecimal, of \f[B]x\f[R] as an unsigned integer in as few power of two bytes as possible. Both outputs are split into bytes separated by spaces. .RS .PP If \f[B]x\f[R] is not an integer or is negative, an error message is printed instead, but bc(1) is not reset (see the \f[B]RESET\f[R] section). .PP This is a \f[B]void\f[R] function (see the \f[I]Void Functions\f[R] subsection of the \f[B]FUNCTIONS\f[R] section). .RE .TP \f[B]int(x)\f[R] Outputs the representation, in binary and hexadecimal, of \f[B]x\f[R] as a signed, two\[cq]s-complement integer in as few power of two bytes as possible. Both outputs are split into bytes separated by spaces. .RS .PP If \f[B]x\f[R] is not an integer, an error message is printed instead, but bc(1) is not reset (see the \f[B]RESET\f[R] section). .PP This is a \f[B]void\f[R] function (see the \f[I]Void Functions\f[R] subsection of the \f[B]FUNCTIONS\f[R] section). .RE .TP \f[B]uintn(x, n)\f[R] Outputs the representation, in binary and hexadecimal, of \f[B]x\f[R] as an unsigned integer in \f[B]n\f[R] bytes. Both outputs are split into bytes separated by spaces. .RS .PP If \f[B]x\f[R] is not an integer, is negative, or cannot fit into \f[B]n\f[R] bytes, an error message is printed instead, but bc(1) is not reset (see the \f[B]RESET\f[R] section). .PP This is a \f[B]void\f[R] function (see the \f[I]Void Functions\f[R] subsection of the \f[B]FUNCTIONS\f[R] section). .RE .TP \f[B]intn(x, n)\f[R] Outputs the representation, in binary and hexadecimal, of \f[B]x\f[R] as a signed, two\[cq]s-complement integer in \f[B]n\f[R] bytes. Both outputs are split into bytes separated by spaces. .RS .PP If \f[B]x\f[R] is not an integer or cannot fit into \f[B]n\f[R] bytes, an error message is printed instead, but bc(1) is not reset (see the \f[B]RESET\f[R] section). .PP This is a \f[B]void\f[R] function (see the \f[I]Void Functions\f[R] subsection of the \f[B]FUNCTIONS\f[R] section). .RE .TP \f[B]uint8(x)\f[R] Outputs the representation, in binary and hexadecimal, of \f[B]x\f[R] as an unsigned integer in \f[B]1\f[R] byte. Both outputs are split into bytes separated by spaces. .RS .PP If \f[B]x\f[R] is not an integer, is negative, or cannot fit into \f[B]1\f[R] byte, an error message is printed instead, but bc(1) is not reset (see the \f[B]RESET\f[R] section). .PP This is a \f[B]void\f[R] function (see the \f[I]Void Functions\f[R] subsection of the \f[B]FUNCTIONS\f[R] section). .RE .TP \f[B]int8(x)\f[R] Outputs the representation, in binary and hexadecimal, of \f[B]x\f[R] as a signed, two\[cq]s-complement integer in \f[B]1\f[R] byte. Both outputs are split into bytes separated by spaces. .RS .PP If \f[B]x\f[R] is not an integer or cannot fit into \f[B]1\f[R] byte, an error message is printed instead, but bc(1) is not reset (see the \f[B]RESET\f[R] section). .PP This is a \f[B]void\f[R] function (see the \f[I]Void Functions\f[R] subsection of the \f[B]FUNCTIONS\f[R] section). .RE .TP \f[B]uint16(x)\f[R] Outputs the representation, in binary and hexadecimal, of \f[B]x\f[R] as an unsigned integer in \f[B]2\f[R] bytes. Both outputs are split into bytes separated by spaces. .RS .PP If \f[B]x\f[R] is not an integer, is negative, or cannot fit into \f[B]2\f[R] bytes, an error message is printed instead, but bc(1) is not reset (see the \f[B]RESET\f[R] section). .PP This is a \f[B]void\f[R] function (see the \f[I]Void Functions\f[R] subsection of the \f[B]FUNCTIONS\f[R] section). .RE .TP \f[B]int16(x)\f[R] Outputs the representation, in binary and hexadecimal, of \f[B]x\f[R] as a signed, two\[cq]s-complement integer in \f[B]2\f[R] bytes. Both outputs are split into bytes separated by spaces. .RS .PP If \f[B]x\f[R] is not an integer or cannot fit into \f[B]2\f[R] bytes, an error message is printed instead, but bc(1) is not reset (see the \f[B]RESET\f[R] section). .PP This is a \f[B]void\f[R] function (see the \f[I]Void Functions\f[R] subsection of the \f[B]FUNCTIONS\f[R] section). .RE .TP \f[B]uint32(x)\f[R] Outputs the representation, in binary and hexadecimal, of \f[B]x\f[R] as an unsigned integer in \f[B]4\f[R] bytes. Both outputs are split into bytes separated by spaces. .RS .PP If \f[B]x\f[R] is not an integer, is negative, or cannot fit into \f[B]4\f[R] bytes, an error message is printed instead, but bc(1) is not reset (see the \f[B]RESET\f[R] section). .PP This is a \f[B]void\f[R] function (see the \f[I]Void Functions\f[R] subsection of the \f[B]FUNCTIONS\f[R] section). .RE .TP \f[B]int32(x)\f[R] Outputs the representation, in binary and hexadecimal, of \f[B]x\f[R] as a signed, two\[cq]s-complement integer in \f[B]4\f[R] bytes. Both outputs are split into bytes separated by spaces. .RS .PP If \f[B]x\f[R] is not an integer or cannot fit into \f[B]4\f[R] bytes, an error message is printed instead, but bc(1) is not reset (see the \f[B]RESET\f[R] section). .PP This is a \f[B]void\f[R] function (see the \f[I]Void Functions\f[R] subsection of the \f[B]FUNCTIONS\f[R] section). .RE .TP \f[B]uint64(x)\f[R] Outputs the representation, in binary and hexadecimal, of \f[B]x\f[R] as an unsigned integer in \f[B]8\f[R] bytes. Both outputs are split into bytes separated by spaces. .RS .PP If \f[B]x\f[R] is not an integer, is negative, or cannot fit into \f[B]8\f[R] bytes, an error message is printed instead, but bc(1) is not reset (see the \f[B]RESET\f[R] section). .PP This is a \f[B]void\f[R] function (see the \f[I]Void Functions\f[R] subsection of the \f[B]FUNCTIONS\f[R] section). .RE .TP \f[B]int64(x)\f[R] Outputs the representation, in binary and hexadecimal, of \f[B]x\f[R] as a signed, two\[cq]s-complement integer in \f[B]8\f[R] bytes. Both outputs are split into bytes separated by spaces. .RS .PP If \f[B]x\f[R] is not an integer or cannot fit into \f[B]8\f[R] bytes, an error message is printed instead, but bc(1) is not reset (see the \f[B]RESET\f[R] section). .PP This is a \f[B]void\f[R] function (see the \f[I]Void Functions\f[R] subsection of the \f[B]FUNCTIONS\f[R] section). .RE .TP \f[B]hex_uint(x, n)\f[R] Outputs the representation of the truncated absolute value of \f[B]x\f[R] as an unsigned integer in hexadecimal using \f[B]n\f[R] bytes. Not all of the value will be output if \f[B]n\f[R] is too small. .RS .PP This is a \f[B]void\f[R] function (see the \f[I]Void Functions\f[R] subsection of the \f[B]FUNCTIONS\f[R] section). .RE .TP \f[B]binary_uint(x, n)\f[R] Outputs the representation of the truncated absolute value of \f[B]x\f[R] as an unsigned integer in binary using \f[B]n\f[R] bytes. Not all of the value will be output if \f[B]n\f[R] is too small. .RS .PP This is a \f[B]void\f[R] function (see the \f[I]Void Functions\f[R] subsection of the \f[B]FUNCTIONS\f[R] section). .RE .TP \f[B]output_uint(x, n)\f[R] Outputs the representation of the truncated absolute value of \f[B]x\f[R] as an unsigned integer in the current \f[B]obase\f[R] (see the \f[B]SYNTAX\f[R] section) using \f[B]n\f[R] bytes. Not all of the value will be output if \f[B]n\f[R] is too small. .RS .PP This is a \f[B]void\f[R] function (see the \f[I]Void Functions\f[R] subsection of the \f[B]FUNCTIONS\f[R] section). .RE .TP \f[B]output_byte(x, i)\f[R] Outputs byte \f[B]i\f[R] of the truncated absolute value of \f[B]x\f[R], where \f[B]0\f[R] is the least significant byte and \f[B]number_of_bytes - 1\f[R] is the most significant byte. .RS .PP This is a \f[B]void\f[R] function (see the \f[I]Void Functions\f[R] subsection of the \f[B]FUNCTIONS\f[R] section). .RE .SS Transcendental Functions .PP All transcendental functions can return slightly inaccurate results (up to 1 ULP (https://en.wikipedia.org/wiki/Unit_in_the_last_place)). This is unavoidable, and this article (https://people.eecs.berkeley.edu/~wkahan/LOG10HAF.TXT) explains why it is impossible and unnecessary to calculate exact results for the transcendental functions. .PP Because of the possible inaccuracy, I recommend that users call those functions with the precision (\f[B]scale\f[R]) set to at least 1 higher than is necessary. If exact results are \f[I]absolutely\f[R] required, users can double the precision (\f[B]scale\f[R]) and then truncate. .PP The transcendental functions in the standard math library are: .IP \[bu] 2 \f[B]s(x)\f[R] .IP \[bu] 2 \f[B]c(x)\f[R] .IP \[bu] 2 \f[B]a(x)\f[R] .IP \[bu] 2 \f[B]l(x)\f[R] .IP \[bu] 2 \f[B]e(x)\f[R] .IP \[bu] 2 \f[B]j(x, n)\f[R] .PP The transcendental functions in the extended math library are: .IP \[bu] 2 \f[B]l2(x)\f[R] .IP \[bu] 2 \f[B]l10(x)\f[R] .IP \[bu] 2 \f[B]log(x, b)\f[R] .IP \[bu] 2 \f[B]pi(p)\f[R] .IP \[bu] 2 \f[B]t(x)\f[R] .IP \[bu] 2 \f[B]a2(y, x)\f[R] .IP \[bu] 2 \f[B]sin(x)\f[R] .IP \[bu] 2 \f[B]cos(x)\f[R] .IP \[bu] 2 \f[B]tan(x)\f[R] .IP \[bu] 2 \f[B]atan(x)\f[R] .IP \[bu] 2 \f[B]atan2(y, x)\f[R] .IP \[bu] 2 \f[B]r2d(x)\f[R] .IP \[bu] 2 \f[B]d2r(x)\f[R] .SH RESET .PP When bc(1) encounters an error or a signal that it has a non-default handler for, it resets. This means that several things happen. .PP First, any functions that are executing are stopped and popped off the stack. The behavior is not unlike that of exceptions in programming languages. Then the execution point is set so that any code waiting to execute (after all functions returned) is skipped. .PP Thus, when bc(1) resets, it skips any remaining code waiting to be executed. Then, if it is interactive mode, and the error was not a fatal error (see the \f[B]EXIT STATUS\f[R] section), it asks for more input; otherwise, it exits with the appropriate return code. .PP Note that this reset behavior is different from the GNU bc(1), which attempts to start executing the statement right after the one that caused an error. .SH PERFORMANCE .PP Most bc(1) implementations use \f[B]char\f[R] types to calculate the value of \f[B]1\f[R] decimal digit at a time, but that can be slow. This bc(1) does something different. .PP It uses large integers to calculate more than \f[B]1\f[R] decimal digit at a time. If built in a environment where \f[B]BC_LONG_BIT\f[R] (see the \f[B]LIMITS\f[R] section) is \f[B]64\f[R], then each integer has \f[B]9\f[R] decimal digits. If built in an environment where \f[B]BC_LONG_BIT\f[R] is \f[B]32\f[R] then each integer has \f[B]4\f[R] decimal digits. This value (the number of decimal digits per large integer) is called \f[B]BC_BASE_DIGS\f[R]. .PP The actual values of \f[B]BC_LONG_BIT\f[R] and \f[B]BC_BASE_DIGS\f[R] can be queried with the \f[B]limits\f[R] statement. .PP In addition, this bc(1) uses an even larger integer for overflow checking. This integer type depends on the value of \f[B]BC_LONG_BIT\f[R], but is always at least twice as large as the integer type used to store digits. .SH LIMITS .PP The following are the limits on bc(1): .TP \f[B]BC_LONG_BIT\f[R] The number of bits in the \f[B]long\f[R] type in the environment where bc(1) was built. This determines how many decimal digits can be stored in a single large integer (see the \f[B]PERFORMANCE\f[R] section). .TP \f[B]BC_BASE_DIGS\f[R] The number of decimal digits per large integer (see the \f[B]PERFORMANCE\f[R] section). Depends on \f[B]BC_LONG_BIT\f[R]. .TP \f[B]BC_BASE_POW\f[R] The max decimal number that each large integer can store (see \f[B]BC_BASE_DIGS\f[R]) plus \f[B]1\f[R]. Depends on \f[B]BC_BASE_DIGS\f[R]. .TP \f[B]BC_OVERFLOW_MAX\f[R] The max number that the overflow type (see the \f[B]PERFORMANCE\f[R] section) can hold. Depends on \f[B]BC_LONG_BIT\f[R]. .TP \f[B]BC_BASE_MAX\f[R] The maximum output base. Set at \f[B]BC_BASE_POW\f[R]. .TP \f[B]BC_DIM_MAX\f[R] The maximum size of arrays. Set at \f[B]SIZE_MAX-1\f[R]. .TP \f[B]BC_SCALE_MAX\f[R] The maximum \f[B]scale\f[R]. Set at \f[B]BC_OVERFLOW_MAX-1\f[R]. .TP \f[B]BC_STRING_MAX\f[R] The maximum length of strings. Set at \f[B]BC_OVERFLOW_MAX-1\f[R]. .TP \f[B]BC_NAME_MAX\f[R] The maximum length of identifiers. Set at \f[B]BC_OVERFLOW_MAX-1\f[R]. .TP \f[B]BC_NUM_MAX\f[R] The maximum length of a number (in decimal digits), which includes digits after the decimal point. Set at \f[B]BC_OVERFLOW_MAX-1\f[R]. .TP \f[B]BC_RAND_MAX\f[R] The maximum integer (inclusive) returned by the \f[B]rand()\f[R] operand. Set at \f[B]2\[ha]BC_LONG_BIT-1\f[R]. .TP Exponent The maximum allowable exponent (positive or negative). Set at \f[B]BC_OVERFLOW_MAX\f[R]. .TP Number of vars The maximum number of vars/arrays. Set at \f[B]SIZE_MAX-1\f[R]. .PP The actual values can be queried with the \f[B]limits\f[R] statement. .PP These limits are meant to be effectively non-existent; the limits are so large (at least on 64-bit machines) that there should not be any point at which they become a problem. In fact, memory should be exhausted before these limits should be hit. .SH ENVIRONMENT VARIABLES .PP bc(1) recognizes the following environment variables: .TP \f[B]POSIXLY_CORRECT\f[R] If this variable exists (no matter the contents), bc(1) behaves as if the \f[B]-s\f[R] option was given. .TP \f[B]BC_ENV_ARGS\f[R] This is another way to give command-line arguments to bc(1). They should be in the same format as all other command-line arguments. These are always processed first, so any files given in \f[B]BC_ENV_ARGS\f[R] will be processed before arguments and files given on the command-line. This gives the user the ability to set up \[lq]standard\[rq] options and files to be used at every invocation. The most useful thing for such files to contain would be useful functions that the user might want every time bc(1) runs. .RS .PP The code that parses \f[B]BC_ENV_ARGS\f[R] will correctly handle quoted arguments, but it does not understand escape sequences. For example, the string \f[B]\[lq]/home/gavin/some bc file.bc\[rq]\f[R] will be correctly parsed, but the string \f[B]\[lq]/home/gavin/some \[dq]bc\[dq] file.bc\[rq]\f[R] will include the backslashes. .PP The quote parsing will handle either kind of quotes, \f[B]\[cq]\f[R] or \f[B]\[lq]\f[R]. Thus, if you have a file with any number of single quotes in the name, you can use double quotes as the outside quotes, as in \f[B]\[lq]some `bc' file.bc\[rq]\f[R], and vice versa if you have a file with double quotes. However, handling a file with both kinds of quotes in \f[B]BC_ENV_ARGS\f[R] is not supported due to the complexity of the parsing, though such files are still supported on the command-line where the parsing is done by the shell. .RE .TP \f[B]BC_LINE_LENGTH\f[R] If this environment variable exists and contains an integer that is greater than \f[B]1\f[R] and is less than \f[B]UINT16_MAX\f[R] (\f[B]2\[ha]16-1\f[R]), bc(1) will output lines to that length, including the backslash (\f[B]\[rs]\f[R]). The default line length is \f[B]70\f[R]. .RS .PP The special value of \f[B]0\f[R] will disable line length checking and print numbers without regard to line length and without backslashes and newlines. .RE .TP \f[B]BC_BANNER\f[R] If this environment variable exists and contains an integer, then a non-zero value activates the copyright banner when bc(1) is in interactive mode, while zero deactivates it. .RS .PP If bc(1) is not in interactive mode (see the \f[B]INTERACTIVE MODE\f[R] section), then this environment variable has no effect because bc(1) does not print the banner when not in interactive mode. .PP This environment variable overrides the default, which can be queried with the \f[B]-h\f[R] or \f[B]--help\f[R] options. .RE .TP \f[B]BC_SIGINT_RESET\f[R] If bc(1) is not in interactive mode (see the \f[B]INTERACTIVE MODE\f[R] section), then this environment variable has no effect because bc(1) exits on \f[B]SIGINT\f[R] when not in interactive mode. .RS .PP However, when bc(1) is in interactive mode, then if this environment variable exists and contains an integer, a non-zero value makes bc(1) reset on \f[B]SIGINT\f[R], rather than exit, and zero makes bc(1) exit. If this environment variable exists and is \f[I]not\f[R] an integer, then bc(1) will exit on \f[B]SIGINT\f[R]. .PP This environment variable overrides the default, which can be queried with the \f[B]-h\f[R] or \f[B]--help\f[R] options. .RE .TP \f[B]BC_TTY_MODE\f[R] If TTY mode is \f[I]not\f[R] available (see the \f[B]TTY MODE\f[R] section), then this environment variable has no effect. .RS .PP However, when TTY mode is available, then if this environment variable exists and contains an integer, then a non-zero value makes bc(1) use TTY mode, and zero makes bc(1) not use TTY mode. .PP This environment variable overrides the default, which can be queried with the \f[B]-h\f[R] or \f[B]--help\f[R] options. .RE .TP \f[B]BC_PROMPT\f[R] If TTY mode is \f[I]not\f[R] available (see the \f[B]TTY MODE\f[R] section), then this environment variable has no effect. .RS .PP However, when TTY mode is available, then if this environment variable exists and contains an integer, a non-zero value makes bc(1) use a prompt, and zero or a non-integer makes bc(1) not use a prompt. If this environment variable does not exist and \f[B]BC_TTY_MODE\f[R] does, then the value of the \f[B]BC_TTY_MODE\f[R] environment variable is used. .PP This environment variable and the \f[B]BC_TTY_MODE\f[R] environment variable override the default, which can be queried with the \f[B]-h\f[R] or \f[B]--help\f[R] options. .RE +.TP +\f[B]BC_EXPR_EXIT\f[R] +If any expressions or expression files are given on the command-line +with \f[B]-e\f[R], \f[B]--expression\f[R], \f[B]-f\f[R], or +\f[B]--file\f[R], then if this environment variable exists and contains +an integer, a non-zero value makes bc(1) exit after executing the +expressions and expression files, and a non-zero value makes bc(1) not +exit. +.RS +.PP +This environment variable overrides the default, which can be queried +with the \f[B]-h\f[R] or \f[B]--help\f[R] options. +.RE .SH EXIT STATUS .PP bc(1) returns the following exit statuses: .TP \f[B]0\f[R] No error. .TP \f[B]1\f[R] A math error occurred. This follows standard practice of using \f[B]1\f[R] for expected errors, since math errors will happen in the process of normal execution. .RS .PP Math errors include divide by \f[B]0\f[R], taking the square root of a negative number, using a negative number as a bound for the pseudo-random number generator, attempting to convert a negative number to a hardware integer, overflow when converting a number to a hardware integer, overflow when calculating the size of a number, and attempting to use a non-integer where an integer is required. .PP Converting to a hardware integer happens for the second operand of the power (\f[B]\[ha]\f[R]), places (\f[B]\[at]\f[R]), left shift (\f[B]<<\f[R]), and right shift (\f[B]>>\f[R]) operators and their corresponding assignment operators. .RE .TP \f[B]2\f[R] A parse error occurred. .RS .PP Parse errors include unexpected \f[B]EOF\f[R], using an invalid character, failing to find the end of a string or comment, using a token where it is invalid, giving an invalid expression, giving an invalid print statement, giving an invalid function definition, attempting to assign to an expression that is not a named expression (see the \f[I]Named Expressions\f[R] subsection of the \f[B]SYNTAX\f[R] section), giving an invalid \f[B]auto\f[R] list, having a duplicate \f[B]auto\f[R]/function parameter, failing to find the end of a code block, attempting to return a value from a \f[B]void\f[R] function, attempting to use a variable as a reference, and using any extensions when the option \f[B]-s\f[R] or any equivalents were given. .RE .TP \f[B]3\f[R] A runtime error occurred. .RS .PP Runtime errors include assigning an invalid number to any global (\f[B]ibase\f[R], \f[B]obase\f[R], or \f[B]scale\f[R]), giving a bad expression to a \f[B]read()\f[R] call, calling \f[B]read()\f[R] inside of a \f[B]read()\f[R] call, type errors, passing the wrong number of arguments to functions, attempting to call an undefined function, and attempting to use a \f[B]void\f[R] function call as a value in an expression. .RE .TP \f[B]4\f[R] A fatal error occurred. .RS .PP Fatal errors include memory allocation errors, I/O errors, failing to open files, attempting to use files that do not have only ASCII characters (bc(1) only accepts ASCII characters), attempting to open a directory as a file, and giving invalid command-line options. .RE .PP The exit status \f[B]4\f[R] is special; when a fatal error occurs, bc(1) always exits and returns \f[B]4\f[R], no matter what mode bc(1) is in. .PP The other statuses will only be returned when bc(1) is not in interactive mode (see the \f[B]INTERACTIVE MODE\f[R] section), since bc(1) resets its state (see the \f[B]RESET\f[R] section) and accepts more input when one of those errors occurs in interactive mode. This is also the case when interactive mode is forced by the \f[B]-i\f[R] flag or \f[B]--interactive\f[R] option. .PP These exit statuses allow bc(1) to be used in shell scripting with error checking, and its normal behavior can be forced by using the \f[B]-i\f[R] flag or \f[B]--interactive\f[R] option. .SH INTERACTIVE MODE .PP Per the standard (https://pubs.opengroup.org/onlinepubs/9699919799/utilities/bc.html), bc(1) has an interactive mode and a non-interactive mode. Interactive mode is turned on automatically when both \f[B]stdin\f[R] and \f[B]stdout\f[R] are hooked to a terminal, but the \f[B]-i\f[R] flag and \f[B]--interactive\f[R] option can turn it on in other situations. .PP In interactive mode, bc(1) attempts to recover from errors (see the \f[B]RESET\f[R] section), and in normal execution, flushes \f[B]stdout\f[R] as soon as execution is done for the current input. bc(1) may also reset on \f[B]SIGINT\f[R] instead of exit, depending on the contents of, or default for, the \f[B]BC_SIGINT_RESET\f[R] environment variable (see the \f[B]ENVIRONMENT VARIABLES\f[R] section). .SH TTY MODE .PP If \f[B]stdin\f[R], \f[B]stdout\f[R], and \f[B]stderr\f[R] are all connected to a TTY, then \[lq]TTY mode\[rq] is considered to be available, and thus, bc(1) can turn on TTY mode, subject to some settings. .PP If there is the environment variable \f[B]BC_TTY_MODE\f[R] in the environment (see the \f[B]ENVIRONMENT VARIABLES\f[R] section), then if that environment variable contains a non-zero integer, bc(1) will turn on TTY mode when \f[B]stdin\f[R], \f[B]stdout\f[R], and \f[B]stderr\f[R] are all connected to a TTY. If the \f[B]BC_TTY_MODE\f[R] environment variable exists but is \f[I]not\f[R] a non-zero integer, then bc(1) will not turn TTY mode on. .PP If the environment variable \f[B]BC_TTY_MODE\f[R] does \f[I]not\f[R] exist, the default setting is used. The default setting can be queried with the \f[B]-h\f[R] or \f[B]--help\f[R] options. .PP TTY mode is different from interactive mode because interactive mode is required in the bc(1) specification (https://pubs.opengroup.org/onlinepubs/9699919799/utilities/bc.html), and interactive mode requires only \f[B]stdin\f[R] and \f[B]stdout\f[R] to be connected to a terminal. .SS Prompt .PP If TTY mode is available, then a prompt can be enabled. Like TTY mode itself, it can be turned on or off with an environment variable: \f[B]BC_PROMPT\f[R] (see the \f[B]ENVIRONMENT VARIABLES\f[R] section). .PP If the environment variable \f[B]BC_PROMPT\f[R] exists and is a non-zero integer, then the prompt is turned on when \f[B]stdin\f[R], \f[B]stdout\f[R], and \f[B]stderr\f[R] are connected to a TTY and the \f[B]-P\f[R] and \f[B]--no-prompt\f[R] options were not used. The read prompt will be turned on under the same conditions, except that the \f[B]-R\f[R] and \f[B]--no-read-prompt\f[R] options must also not be used. .PP However, if \f[B]BC_PROMPT\f[R] does not exist, the prompt can be enabled or disabled with the \f[B]BC_TTY_MODE\f[R] environment variable, the \f[B]-P\f[R] and \f[B]--no-prompt\f[R] options, and the \f[B]-R\f[R] and \f[B]--no-read-prompt\f[R] options. See the \f[B]ENVIRONMENT VARIABLES\f[R] and \f[B]OPTIONS\f[R] sections for more details. .SH SIGNAL HANDLING .PP Sending a \f[B]SIGINT\f[R] will cause bc(1) to do one of two things. .PP If bc(1) is not in interactive mode (see the \f[B]INTERACTIVE MODE\f[R] section), or the \f[B]BC_SIGINT_RESET\f[R] environment variable (see the \f[B]ENVIRONMENT VARIABLES\f[R] section), or its default, is either not an integer or it is zero, bc(1) will exit. .PP However, if bc(1) is in interactive mode, and the \f[B]BC_SIGINT_RESET\f[R] or its default is an integer and non-zero, then bc(1) will stop executing the current input and reset (see the \f[B]RESET\f[R] section) upon receiving a \f[B]SIGINT\f[R]. .PP Note that \[lq]current input\[rq] can mean one of two things. If bc(1) is processing input from \f[B]stdin\f[R] in interactive mode, it will ask for more input. If bc(1) is processing input from a file in interactive mode, it will stop processing the file and start processing the next file, if one exists, or ask for input from \f[B]stdin\f[R] if no other file exists. .PP This means that if a \f[B]SIGINT\f[R] is sent to bc(1) as it is executing a file, it can seem as though bc(1) did not respond to the signal since it will immediately start executing the next file. This is by design; most files that users execute when interacting with bc(1) have function definitions, which are quick to parse. If a file takes a long time to execute, there may be a bug in that file. The rest of the files could still be executed without problem, allowing the user to continue. .PP \f[B]SIGTERM\f[R] and \f[B]SIGQUIT\f[R] cause bc(1) to clean up and exit, and it uses the default handler for all other signals. .SH LOCALES .PP This bc(1) ships with support for adding error messages for different locales and thus, supports \f[B]LC_MESSAGES\f[R]. .SH SEE ALSO .PP dc(1) .SH STANDARDS .PP bc(1) is compliant with the IEEE Std 1003.1-2017 (\[lq]POSIX.1-2017\[rq]) (https://pubs.opengroup.org/onlinepubs/9699919799/utilities/bc.html) specification. The flags \f[B]-efghiqsvVw\f[R], all long options, and the extensions noted above are extensions to that specification. .PP Note that the specification explicitly says that bc(1) only accepts numbers that use a period (\f[B].\f[R]) as a radix point, regardless of the value of \f[B]LC_NUMERIC\f[R]. .PP This bc(1) supports error messages for different locales, and thus, it supports \f[B]LC_MESSAGES\f[R]. .SH BUGS .PP None are known. Report bugs at https://git.yzena.com/gavin/bc. .SH AUTHORS .PP Gavin D. Howard and contributors. diff --git a/contrib/bc/manuals/bc/H.1.md b/contrib/bc/manuals/bc/H.1.md index 99c88db93230..47b17f1188e4 100644 --- a/contrib/bc/manuals/bc/H.1.md +++ b/contrib/bc/manuals/bc/H.1.md @@ -1,2321 +1,2332 @@ # NAME bc - arbitrary-precision decimal arithmetic language and calculator # SYNOPSIS **bc** [**-ghilPqRsvVw**] [**-\-global-stacks**] [**-\-help**] [**-\-interactive**] [**-\-mathlib**] [**-\-no-prompt**] [**-\-no-read-prompt**] [**-\-quiet**] [**-\-standard**] [**-\-warn**] [**-\-version**] [**-e** *expr*] [**-\-expression**=*expr*...] [**-f** *file*...] [**-\-file**=*file*...] [*file*...] # DESCRIPTION bc(1) is an interactive processor for a language first standardized in 1991 by POSIX. (The current standard is [here][1].) The language provides unlimited precision decimal arithmetic and is somewhat C-like, but there are differences. Such differences will be noted in this document. After parsing and handling options, this bc(1) reads any files given on the command line and executes them before reading from **stdin**. This bc(1) is a drop-in replacement for *any* bc(1), including (and especially) the GNU bc(1). It also has many extensions and extra features beyond other implementations. **Note**: If running this bc(1) on *any* script meant for another bc(1) gives a parse error, it is probably because a word this bc(1) reserves as a keyword is used as the name of a function, variable, or array. To fix that, use the command-line option **-r** *keyword*, where *keyword* is the keyword that is used as a name in the script. For more information, see the **OPTIONS** section. If parsing scripts meant for other bc(1) implementations still does not work, that is a bug and should be reported. See the **BUGS** section. # OPTIONS The following are the options that bc(1) accepts. **-g**, **-\-global-stacks** : Turns the globals **ibase**, **obase**, **scale**, and **seed** into stacks. This has the effect that a copy of the current value of all four are pushed onto a stack for every function call, as well as popped when every function returns. This means that functions can assign to any and all of those globals without worrying that the change will affect other functions. Thus, a hypothetical function named **output(x,b)** that simply printed **x** in base **b** could be written like this: define void output(x, b) { obase=b x } instead of like this: define void output(x, b) { auto c c=obase obase=b x obase=c } This makes writing functions much easier. (**Note**: the function **output(x,b)** exists in the extended math library. See the **LIBRARY** section.) However, since using this flag means that functions cannot set **ibase**, **obase**, **scale**, or **seed** globally, functions that are made to do so cannot work anymore. There are two possible use cases for that, and each has a solution. First, if a function is called on startup to turn bc(1) into a number converter, it is possible to replace that capability with various shell aliases. Examples: alias d2o="bc -e ibase=A -e obase=8" alias h2b="bc -e ibase=G -e obase=2" Second, if the purpose of a function is to set **ibase**, **obase**, **scale**, or **seed** globally for any other purpose, it could be split into one to four functions (based on how many globals it sets) and each of those functions could return the desired value for a global. For functions that set **seed**, the value assigned to **seed** is not propagated to parent functions. This means that the sequence of pseudo-random numbers that they see will not be the same sequence of pseudo-random numbers that any parent sees. This is only the case once **seed** has been set. If a function desires to not affect the sequence of pseudo-random numbers of its parents, but wants to use the same **seed**, it can use the following line: seed = seed If the behavior of this option is desired for every run of bc(1), then users could make sure to define **BC_ENV_ARGS** and include this option (see the **ENVIRONMENT VARIABLES** section for more details). If **-s**, **-w**, or any equivalents are used, this option is ignored. This is a **non-portable extension**. **-h**, **-\-help** : Prints a usage message and quits. **-i**, **-\-interactive** : Forces interactive mode. (See the **INTERACTIVE MODE** section.) This is a **non-portable extension**. **-L**, **-\-no-line-length** : Disables line length checking and prints numbers without backslashes and newlines. In other words, this option sets **BC_LINE_LENGTH** to **0** (see the **ENVIRONMENT VARIABLES** section). This is a **non-portable extension**. **-l**, **-\-mathlib** : Sets **scale** (see the **SYNTAX** section) to **20** and loads the included math library and the extended math library before running any code, including any expressions or files specified on the command line. To learn what is in the libraries, see the **LIBRARY** section. **-P**, **-\-no-prompt** : Disables the prompt in TTY mode. (The prompt is only enabled in TTY mode. See the **TTY MODE** section.) This is mostly for those users that do not want a prompt or are not used to having them in bc(1). Most of those users would want to put this option in **BC_ENV_ARGS** (see the **ENVIRONMENT VARIABLES** section). These options override the **BC_PROMPT** and **BC_TTY_MODE** environment variables (see the **ENVIRONMENT VARIABLES** section). This is a **non-portable extension**. **-R**, **-\-no-read-prompt** : Disables the read prompt in TTY mode. (The read prompt is only enabled in TTY mode. See the **TTY MODE** section.) This is mostly for those users that do not want a read prompt or are not used to having them in bc(1). Most of those users would want to put this option in **BC_ENV_ARGS** (see the **ENVIRONMENT VARIABLES** section). This option is also useful in hash bang lines of bc(1) scripts that prompt for user input. This option does not disable the regular prompt because the read prompt is only used when the **read()** built-in function is called. These options *do* override the **BC_PROMPT** and **BC_TTY_MODE** environment variables (see the **ENVIRONMENT VARIABLES** section), but only for the read prompt. This is a **non-portable extension**. **-r** *keyword*, **-\-redefine**=*keyword* : Redefines *keyword* in order to allow it to be used as a function, variable, or array name. This is useful when this bc(1) gives parse errors when parsing scripts meant for other bc(1) implementations. The keywords this bc(1) allows to be redefined are: * **abs** * **asciify** * **continue** * **divmod** * **else** * **halt** * **irand** * **last** * **limits** * **maxibase** * **maxobase** * **maxrand** * **maxscale** * **modexp** * **print** * **rand** * **read** * **seed** * **stream** If any of those keywords are used as a function, variable, or array name in a script, use this option with the keyword as the argument. If multiple are used, use this option for all of them; it can be used multiple times. Keywords are *not* redefined when parsing the builtin math library (see the **LIBRARY** section). It is a fatal error to redefine keywords mandated by the POSIX standard. It is a fatal error to attempt to redefine words that this bc(1) does not reserve as keywords. **-q**, **-\-quiet** : This option is for compatibility with the [GNU bc(1)][2]; it is a no-op. Without this option, GNU bc(1) prints a copyright header. This bc(1) only prints the copyright header if one or more of the **-v**, **-V**, or **-\-version** options are given. This is a **non-portable extension**. **-s**, **-\-standard** : Process exactly the language defined by the [standard][1] and error if any extensions are used. This is a **non-portable extension**. **-v**, **-V**, **-\-version** : Print the version information (copyright header) and exit. This is a **non-portable extension**. **-w**, **-\-warn** : Like **-s** and **-\-standard**, except that warnings (and not errors) are printed for non-standard extensions and execution continues normally. This is a **non-portable extension**. **-z**, **-\-leading-zeroes** : Makes bc(1) print all numbers greater than **-1** and less than **1**, and not equal to **0**, with a leading zero. This can be set for individual numbers with the **plz(x)**, plznl(x)**, **pnlz(x)**, and **pnlznl(x)** functions in the extended math library (see the **LIBRARY** section). This is a **non-portable extension**. **-e** *expr*, **-\-expression**=*expr* : Evaluates *expr*. If multiple expressions are given, they are evaluated in order. If files are given as well (see below), the expressions and files are evaluated in the order given. This means that if a file is given before an expression, the file is read in and evaluated first. If this option is given on the command-line (i.e., not in **BC_ENV_ARGS**, see the **ENVIRONMENT VARIABLES** section), then after processing all expressions and files, bc(1) will exit, unless **-** (**stdin**) was given as an argument at least once to **-f** or **-\-file**, whether on the command-line or in **BC_ENV_ARGS**. However, if any other **-e**, **-\-expression**, **-f**, or **-\-file** arguments are given after **-f-** or equivalent is given, bc(1) will give a fatal error and exit. This is a **non-portable extension**. **-f** *file*, **-\-file**=*file* : Reads in *file* and evaluates it, line by line, as though it were read through **stdin**. If expressions are also given (see above), the expressions are evaluated in the order given. If this option is given on the command-line (i.e., not in **BC_ENV_ARGS**, see the **ENVIRONMENT VARIABLES** section), then after processing all expressions and files, bc(1) will exit, unless **-** (**stdin**) was given as an argument at least once to **-f** or **-\-file**. However, if any other **-e**, **-\-expression**, **-f**, or **-\-file** arguments are given after **-f-** or equivalent is given, bc(1) will give a fatal error and exit. This is a **non-portable extension**. All long options are **non-portable extensions**. # STDIN If no files or expressions are given by the **-f**, **-\-file**, **-e**, or **-\-expression** options, then bc(1) read from **stdin**. However, there are a few caveats to this. First, **stdin** is evaluated a line at a time. The only exception to this is if the parse cannot complete. That means that starting a string without ending it or starting a function, **if** statement, or loop without ending it will also cause bc(1) to not execute. Second, after an **if** statement, bc(1) doesn't know if an **else** statement will follow, so it will not execute until it knows there will not be an **else** statement. # STDOUT Any non-error output is written to **stdout**. In addition, if history (see the **HISTORY** section) and the prompt (see the **TTY MODE** section) are enabled, both are output to **stdout**. **Note**: Unlike other bc(1) implementations, this bc(1) will issue a fatal error (see the **EXIT STATUS** section) if it cannot write to **stdout**, so if **stdout** is closed, as in **bc >&-**, it will quit with an error. This is done so that bc(1) can report problems when **stdout** is redirected to a file. If there are scripts that depend on the behavior of other bc(1) implementations, it is recommended that those scripts be changed to redirect **stdout** to **/dev/null**. # STDERR Any error output is written to **stderr**. **Note**: Unlike other bc(1) implementations, this bc(1) will issue a fatal error (see the **EXIT STATUS** section) if it cannot write to **stderr**, so if **stderr** is closed, as in **bc 2>&-**, it will quit with an error. This is done so that bc(1) can exit with an error code when **stderr** is redirected to a file. If there are scripts that depend on the behavior of other bc(1) implementations, it is recommended that those scripts be changed to redirect **stderr** to **/dev/null**. # SYNTAX The syntax for bc(1) programs is mostly C-like, with some differences. This bc(1) follows the [POSIX standard][1], which is a much more thorough resource for the language this bc(1) accepts. This section is meant to be a summary and a listing of all the extensions to the standard. In the sections below, **E** means expression, **S** means statement, and **I** means identifier. Identifiers (**I**) start with a lowercase letter and can be followed by any number (up to **BC_NAME_MAX-1**) of lowercase letters (**a-z**), digits (**0-9**), and underscores (**\_**). The regex is **\[a-z\]\[a-z0-9\_\]\***. Identifiers with more than one character (letter) are a **non-portable extension**. **ibase** is a global variable determining how to interpret constant numbers. It is the "input" base, or the number base used for interpreting input numbers. **ibase** is initially **10**. If the **-s** (**-\-standard**) and **-w** (**-\-warn**) flags were not given on the command line, the max allowable value for **ibase** is **36**. Otherwise, it is **16**. The min allowable value for **ibase** is **2**. The max allowable value for **ibase** can be queried in bc(1) programs with the **maxibase()** built-in function. **obase** is a global variable determining how to output results. It is the "output" base, or the number base used for outputting numbers. **obase** is initially **10**. The max allowable value for **obase** is **BC_BASE_MAX** and can be queried in bc(1) programs with the **maxobase()** built-in function. The min allowable value for **obase** is **0**. If **obase** is **0**, values are output in scientific notation, and if **obase** is **1**, values are output in engineering notation. Otherwise, values are output in the specified base. Outputting in scientific and engineering notations are **non-portable extensions**. The *scale* of an expression is the number of digits in the result of the expression right of the decimal point, and **scale** is a global variable that sets the precision of any operations, with exceptions. **scale** is initially **0**. **scale** cannot be negative. The max allowable value for **scale** is **BC_SCALE_MAX** and can be queried in bc(1) programs with the **maxscale()** built-in function. bc(1) has both *global* variables and *local* variables. All *local* variables are local to the function; they are parameters or are introduced in the **auto** list of a function (see the **FUNCTIONS** section). If a variable is accessed which is not a parameter or in the **auto** list, it is assumed to be *global*. If a parent function has a *local* variable version of a variable that a child function considers *global*, the value of that *global* variable in the child function is the value of the variable in the parent function, not the value of the actual *global* variable. All of the above applies to arrays as well. The value of a statement that is an expression (i.e., any of the named expressions or operands) is printed unless the lowest precedence operator is an assignment operator *and* the expression is notsurrounded by parentheses. The value that is printed is also assigned to the special variable **last**. A single dot (**.**) may also be used as a synonym for **last**. These are **non-portable extensions**. Either semicolons or newlines may separate statements. ## Comments There are two kinds of comments: 1. Block comments are enclosed in **/\*** and **\*/**. 2. Line comments go from **#** until, and not including, the next newline. This is a **non-portable extension**. ## Named Expressions The following are named expressions in bc(1): 1. Variables: **I** 2. Array Elements: **I[E]** 3. **ibase** 4. **obase** 5. **scale** 6. **seed** 7. **last** or a single dot (**.**) Numbers 6 and 7 are **non-portable extensions**. The meaning of **seed** is dependent on the current pseudo-random number generator but is guaranteed to not change except for new major versions. The *scale* and sign of the value may be significant. If a previously used **seed** value is assigned to **seed** and used again, the pseudo-random number generator is guaranteed to produce the same sequence of pseudo-random numbers as it did when the **seed** value was previously used. The exact value assigned to **seed** is not guaranteed to be returned if **seed** is queried again immediately. However, if **seed** *does* return a different value, both values, when assigned to **seed**, are guaranteed to produce the same sequence of pseudo-random numbers. This means that certain values assigned to **seed** will *not* produce unique sequences of pseudo-random numbers. The value of **seed** will change after any use of the **rand()** and **irand(E)** operands (see the *Operands* subsection below), except if the parameter passed to **irand(E)** is **0**, **1**, or negative. There is no limit to the length (number of significant decimal digits) or *scale* of the value that can be assigned to **seed**. Variables and arrays do not interfere; users can have arrays named the same as variables. This also applies to functions (see the **FUNCTIONS** section), so a user can have a variable, array, and function that all have the same name, and they will not shadow each other, whether inside of functions or not. Named expressions are required as the operand of **increment**/**decrement** operators and as the left side of **assignment** operators (see the *Operators* subsection). ## Operands The following are valid operands in bc(1): 1. Numbers (see the *Numbers* subsection below). 2. Array indices (**I[E]**). 3. **(E)**: The value of **E** (used to change precedence). 4. **sqrt(E)**: The square root of **E**. **E** must be non-negative. 5. **length(E)**: The number of significant decimal digits in **E**. Returns **1** for **0** with no decimal places. If given a string, the length of the string is returned. Passing a string to **length(E)** is a **non-portable extension**. 6. **length(I[])**: The number of elements in the array **I**. This is a **non-portable extension**. 7. **scale(E)**: The *scale* of **E**. 8. **abs(E)**: The absolute value of **E**. This is a **non-portable extension**. 9. **modexp(E, E, E)**: Modular exponentiation, where the first expression is the base, the second is the exponent, and the third is the modulus. All three values must be integers. The second argument must be non-negative. The third argument must be non-zero. This is a **non-portable extension**. 10. **divmod(E, E, I[])**: Division and modulus in one operation. This is for optimization. The first expression is the dividend, and the second is the divisor, which must be non-zero. The return value is the quotient, and the modulus is stored in index **0** of the provided array (the last argument). This is a **non-portable extension**. 11. **asciify(E)**: If **E** is a string, returns a string that is the first letter of its argument. If it is a number, calculates the number mod **256** and returns that number as a one-character string. This is a **non-portable extension**. 12. **I()**, **I(E)**, **I(E, E)**, and so on, where **I** is an identifier for a non-**void** function (see the *Void Functions* subsection of the **FUNCTIONS** section). The **E** argument(s) may also be arrays of the form **I[]**, which will automatically be turned into array references (see the *Array References* subsection of the **FUNCTIONS** section) if the corresponding parameter in the function definition is an array reference. 13. **read()**: Reads a line from **stdin** and uses that as an expression. The result of that expression is the result of the **read()** operand. This is a **non-portable extension**. 14. **maxibase()**: The max allowable **ibase**. This is a **non-portable extension**. 15. **maxobase()**: The max allowable **obase**. This is a **non-portable extension**. 16. **maxscale()**: The max allowable **scale**. This is a **non-portable extension**. 17. **line_length()**: The line length set with **BC_LINE_LENGTH** (see the **ENVIRONMENT VARIABLES** section). This is a **non-portable extension**. 18. **global_stacks()**: **0** if global stacks are not enabled with the **-g** or **-\-global-stacks** options, non-zero otherwise. See the **OPTIONS** section. This is a **non-portable extension**. 19. **leading_zero()**: **0** if leading zeroes are not enabled with the **-z** or **--leading-zeroes** options, non-zero otherwise. See the **OPTIONS** section. This is a **non-portable extension**. 20. **rand()**: A pseudo-random integer between **0** (inclusive) and **BC_RAND_MAX** (inclusive). Using this operand will change the value of **seed**. This is a **non-portable extension**. 21. **irand(E)**: A pseudo-random integer between **0** (inclusive) and the value of **E** (exclusive). If **E** is negative or is a non-integer (**E**'s *scale* is not **0**), an error is raised, and bc(1) resets (see the **RESET** section) while **seed** remains unchanged. If **E** is larger than **BC_RAND_MAX**, the higher bound is honored by generating several pseudo-random integers, multiplying them by appropriate powers of **BC_RAND_MAX+1**, and adding them together. Thus, the size of integer that can be generated with this operand is unbounded. Using this operand will change the value of **seed**, unless the value of **E** is **0** or **1**. In that case, **0** is returned, and **seed** is *not* changed. This is a **non-portable extension**. 22. **maxrand()**: The max integer returned by **rand()**. This is a **non-portable extension**. The integers generated by **rand()** and **irand(E)** are guaranteed to be as unbiased as possible, subject to the limitations of the pseudo-random number generator. **Note**: The values returned by the pseudo-random number generator with **rand()** and **irand(E)** are guaranteed to *NOT* be cryptographically secure. This is a consequence of using a seeded pseudo-random number generator. However, they *are* guaranteed to be reproducible with identical **seed** values. This means that the pseudo-random values from bc(1) should only be used where a reproducible stream of pseudo-random numbers is *ESSENTIAL*. In any other case, use a non-seeded pseudo-random number generator. ## Numbers Numbers are strings made up of digits, uppercase letters, and at most **1** period for a radix. Numbers can have up to **BC_NUM_MAX** digits. Uppercase letters are equal to **9** + their position in the alphabet (i.e., **A** equals **10**, or **9+1**). If a digit or letter makes no sense with the current value of **ibase**, they are set to the value of the highest valid digit in **ibase**. Single-character numbers (i.e., **A** alone) take the value that they would have if they were valid digits, regardless of the value of **ibase**. This means that **A** alone always equals decimal **10** and **Z** alone always equals decimal **35**. In addition, bc(1) accepts numbers in scientific notation. These have the form **\e\**. The exponent (the portion after the **e**) must be an integer. An example is **1.89237e9**, which is equal to **1892370000**. Negative exponents are also allowed, so **4.2890e-3** is equal to **0.0042890**. Using scientific notation is an error or warning if the **-s** or **-w**, respectively, command-line options (or equivalents) are given. **WARNING**: Both the number and the exponent in scientific notation are interpreted according to the current **ibase**, but the number is still multiplied by **10\^exponent** regardless of the current **ibase**. For example, if **ibase** is **16** and bc(1) is given the number string **FFeA**, the resulting decimal number will be **2550000000000**, and if bc(1) is given the number string **10e-4**, the resulting decimal number will be **0.0016**. Accepting input as scientific notation is a **non-portable extension**. ## Operators The following arithmetic and logical operators can be used. They are listed in order of decreasing precedence. Operators in the same group have the same precedence. **++** **-\-** : Type: Prefix and Postfix Associativity: None Description: **increment**, **decrement** **-** **!** : Type: Prefix Associativity: None Description: **negation**, **boolean not** **\$** : Type: Postfix Associativity: None Description: **truncation** **\@** : Type: Binary Associativity: Right Description: **set precision** **\^** : Type: Binary Associativity: Right Description: **power** **\*** **/** **%** : Type: Binary Associativity: Left Description: **multiply**, **divide**, **modulus** **+** **-** : Type: Binary Associativity: Left Description: **add**, **subtract** **\<\<** **\>\>** : Type: Binary Associativity: Left Description: **shift left**, **shift right** **=** **\<\<=** **\>\>=** **+=** **-=** **\*=** **/=** **%=** **\^=** **\@=** : Type: Binary Associativity: Right Description: **assignment** **==** **\<=** **\>=** **!=** **\<** **\>** : Type: Binary Associativity: Left Description: **relational** **&&** : Type: Binary Associativity: Left Description: **boolean and** **||** : Type: Binary Associativity: Left Description: **boolean or** The operators will be described in more detail below. **++** **-\-** : The prefix and postfix **increment** and **decrement** operators behave exactly like they would in C. They require a named expression (see the *Named Expressions* subsection) as an operand. The prefix versions of these operators are more efficient; use them where possible. **-** : The **negation** operator returns **0** if a user attempts to negate any expression with the value **0**. Otherwise, a copy of the expression with its sign flipped is returned. **!** : The **boolean not** operator returns **1** if the expression is **0**, or **0** otherwise. This is a **non-portable extension**. **\$** : The **truncation** operator returns a copy of the given expression with all of its *scale* removed. This is a **non-portable extension**. **\@** : The **set precision** operator takes two expressions and returns a copy of the first with its *scale* equal to the value of the second expression. That could either mean that the number is returned without change (if the *scale* of the first expression matches the value of the second expression), extended (if it is less), or truncated (if it is more). The second expression must be an integer (no *scale*) and non-negative. This is a **non-portable extension**. **\^** : The **power** operator (not the **exclusive or** operator, as it would be in C) takes two expressions and raises the first to the power of the value of the second. The *scale* of the result is equal to **scale**. The second expression must be an integer (no *scale*), and if it is negative, the first value must be non-zero. **\*** : The **multiply** operator takes two expressions, multiplies them, and returns the product. If **a** is the *scale* of the first expression and **b** is the *scale* of the second expression, the *scale* of the result is equal to **min(a+b,max(scale,a,b))** where **min()** and **max()** return the obvious values. **/** : The **divide** operator takes two expressions, divides them, and returns the quotient. The *scale* of the result shall be the value of **scale**. The second expression must be non-zero. **%** : The **modulus** operator takes two expressions, **a** and **b**, and evaluates them by 1) Computing **a/b** to current **scale** and 2) Using the result of step 1 to calculate **a-(a/b)\*b** to *scale* **max(scale+scale(b),scale(a))**. The second expression must be non-zero. **+** : The **add** operator takes two expressions, **a** and **b**, and returns the sum, with a *scale* equal to the max of the *scale*s of **a** and **b**. **-** : The **subtract** operator takes two expressions, **a** and **b**, and returns the difference, with a *scale* equal to the max of the *scale*s of **a** and **b**. **\<\<** : The **left shift** operator takes two expressions, **a** and **b**, and returns a copy of the value of **a** with its decimal point moved **b** places to the right. The second expression must be an integer (no *scale*) and non-negative. This is a **non-portable extension**. **\>\>** : The **right shift** operator takes two expressions, **a** and **b**, and returns a copy of the value of **a** with its decimal point moved **b** places to the left. The second expression must be an integer (no *scale*) and non-negative. This is a **non-portable extension**. **=** **\<\<=** **\>\>=** **+=** **-=** **\*=** **/=** **%=** **\^=** **\@=** : The **assignment** operators take two expressions, **a** and **b** where **a** is a named expression (see the *Named Expressions* subsection). For **=**, **b** is copied and the result is assigned to **a**. For all others, **a** and **b** are applied as operands to the corresponding arithmetic operator and the result is assigned to **a**. The **assignment** operators that correspond to operators that are extensions are themselves **non-portable extensions**. **==** **\<=** **\>=** **!=** **\<** **\>** : The **relational** operators compare two expressions, **a** and **b**, and if the relation holds, according to C language semantics, the result is **1**. Otherwise, it is **0**. Note that unlike in C, these operators have a lower precedence than the **assignment** operators, which means that **a=b\>c** is interpreted as **(a=b)\>c**. Also, unlike the [standard][1] requires, these operators can appear anywhere any other expressions can be used. This allowance is a **non-portable extension**. **&&** : The **boolean and** operator takes two expressions and returns **1** if both expressions are non-zero, **0** otherwise. This is *not* a short-circuit operator. This is a **non-portable extension**. **||** : The **boolean or** operator takes two expressions and returns **1** if one of the expressions is non-zero, **0** otherwise. This is *not* a short-circuit operator. This is a **non-portable extension**. ## Statements The following items are statements: 1. **E** 2. **{** **S** **;** ... **;** **S** **}** 3. **if** **(** **E** **)** **S** 4. **if** **(** **E** **)** **S** **else** **S** 5. **while** **(** **E** **)** **S** 6. **for** **(** **E** **;** **E** **;** **E** **)** **S** 7. An empty statement 8. **break** 9. **continue** 10. **quit** 11. **halt** 12. **limits** 13. A string of characters, enclosed in double quotes 14. **print** **E** **,** ... **,** **E** 15. **stream** **E** **,** ... **,** **E** 16. **I()**, **I(E)**, **I(E, E)**, and so on, where **I** is an identifier for a **void** function (see the *Void Functions* subsection of the **FUNCTIONS** section). The **E** argument(s) may also be arrays of the form **I[]**, which will automatically be turned into array references (see the *Array References* subsection of the **FUNCTIONS** section) if the corresponding parameter in the function definition is an array reference. Numbers 4, 9, 11, 12, 14, 15, and 16 are **non-portable extensions**. Also, as a **non-portable extension**, any or all of the expressions in the header of a for loop may be omitted. If the condition (second expression) is omitted, it is assumed to be a constant **1**. The **break** statement causes a loop to stop iterating and resume execution immediately following a loop. This is only allowed in loops. The **continue** statement causes a loop iteration to stop early and returns to the start of the loop, including testing the loop condition. This is only allowed in loops. The **if** **else** statement does the same thing as in C. The **quit** statement causes bc(1) to quit, even if it is on a branch that will not be executed (it is a compile-time command). The **halt** statement causes bc(1) to quit, if it is executed. (Unlike **quit** if it is on a branch of an **if** statement that is not executed, bc(1) does not quit.) The **limits** statement prints the limits that this bc(1) is subject to. This is like the **quit** statement in that it is a compile-time command. An expression by itself is evaluated and printed, followed by a newline. Both scientific notation and engineering notation are available for printing the results of expressions. Scientific notation is activated by assigning **0** to **obase**, and engineering notation is activated by assigning **1** to **obase**. To deactivate them, just assign a different value to **obase**. Scientific notation and engineering notation are disabled if bc(1) is run with either the **-s** or **-w** command-line options (or equivalents). Printing numbers in scientific notation and/or engineering notation is a **non-portable extension**. ## Strings If strings appear as a statement by themselves, they are printed without a trailing newline. In addition to appearing as a lone statement by themselves, strings can be assigned to variables and array elements. They can also be passed to functions in variable parameters. If any statement that expects a string is given a variable that had a string assigned to it, the statement acts as though it had received a string. If any math operation is attempted on a string or a variable or array element that has been assigned a string, an error is raised, and bc(1) resets (see the **RESET** section). Assigning strings to variables and array elements and passing them to functions are **non-portable extensions**. ## Print Statement The "expressions" in a **print** statement may also be strings. If they are, there are backslash escape sequences that are interpreted specially. What those sequences are, and what they cause to be printed, are shown below: **\\a**: **\\a** **\\b**: **\\b** **\\\\**: **\\** **\\e**: **\\** **\\f**: **\\f** **\\n**: **\\n** **\\q**: **"** **\\r**: **\\r** **\\t**: **\\t** Any other character following a backslash causes the backslash and character to be printed as-is. Any non-string expression in a print statement shall be assigned to **last**, like any other expression that is printed. ## Stream Statement The "expressions in a **stream** statement may also be strings. If a **stream** statement is given a string, it prints the string as though the string had appeared as its own statement. In other words, the **stream** statement prints strings normally, without a newline. If a **stream** statement is given a number, a copy of it is truncated and its absolute value is calculated. The result is then printed as though **obase** is **256** and each digit is interpreted as an 8-bit ASCII character, making it a byte stream. ## Order of Evaluation All expressions in a statment are evaluated left to right, except as necessary to maintain order of operations. This means, for example, assuming that **i** is equal to **0**, in the expression a[i++] = i++ the first (or 0th) element of **a** is set to **1**, and **i** is equal to **2** at the end of the expression. This includes function arguments. Thus, assuming **i** is equal to **0**, this means that in the expression x(i++, i++) the first argument passed to **x()** is **0**, and the second argument is **1**, while **i** is equal to **2** before the function starts executing. # FUNCTIONS Function definitions are as follows: ``` define I(I,...,I){ auto I,...,I S;...;S return(E) } ``` Any **I** in the parameter list or **auto** list may be replaced with **I[]** to make a parameter or **auto** var an array, and any **I** in the parameter list may be replaced with **\*I[]** to make a parameter an array reference. Callers of functions that take array references should not put an asterisk in the call; they must be called with just **I[]** like normal array parameters and will be automatically converted into references. As a **non-portable extension**, the opening brace of a **define** statement may appear on the next line. As a **non-portable extension**, the return statement may also be in one of the following forms: 1. **return** 2. **return** **(** **)** 3. **return** **E** The first two, or not specifying a **return** statement, is equivalent to **return (0)**, unless the function is a **void** function (see the *Void Functions* subsection below). ## Void Functions Functions can also be **void** functions, defined as follows: ``` define void I(I,...,I){ auto I,...,I S;...;S return } ``` They can only be used as standalone expressions, where such an expression would be printed alone, except in a print statement. Void functions can only use the first two **return** statements listed above. They can also omit the return statement entirely. The word "void" is not treated as a keyword; it is still possible to have variables, arrays, and functions named **void**. The word "void" is only treated specially right after the **define** keyword. This is a **non-portable extension**. ## Array References For any array in the parameter list, if the array is declared in the form ``` *I[] ``` it is a **reference**. Any changes to the array in the function are reflected, when the function returns, to the array that was passed in. Other than this, all function arguments are passed by value. This is a **non-portable extension**. # LIBRARY All of the functions below, including the functions in the extended math library (see the *Extended Library* subsection below), are available when the **-l** or **-\-mathlib** command-line flags are given, except that the extended math library is not available when the **-s** option, the **-w** option, or equivalents are given. ## Standard Library The [standard][1] defines the following functions for the math library: **s(x)** : Returns the sine of **x**, which is assumed to be in radians. This is a transcendental function (see the *Transcendental Functions* subsection below). **c(x)** : Returns the cosine of **x**, which is assumed to be in radians. This is a transcendental function (see the *Transcendental Functions* subsection below). **a(x)** : Returns the arctangent of **x**, in radians. This is a transcendental function (see the *Transcendental Functions* subsection below). **l(x)** : Returns the natural logarithm of **x**. This is a transcendental function (see the *Transcendental Functions* subsection below). **e(x)** : Returns the mathematical constant **e** raised to the power of **x**. This is a transcendental function (see the *Transcendental Functions* subsection below). **j(x, n)** : Returns the bessel integer order **n** (truncated) of **x**. This is a transcendental function (see the *Transcendental Functions* subsection below). ## Extended Library The extended library is *not* loaded when the **-s**/**-\-standard** or **-w**/**-\-warn** options are given since they are not part of the library defined by the [standard][1]. The extended library is a **non-portable extension**. **p(x, y)** : Calculates **x** to the power of **y**, even if **y** is not an integer, and returns the result to the current **scale**. It is an error if **y** is negative and **x** is **0**. This is a transcendental function (see the *Transcendental Functions* subsection below). **r(x, p)** : Returns **x** rounded to **p** decimal places according to the rounding mode [round half away from **0**][3]. **ceil(x, p)** : Returns **x** rounded to **p** decimal places according to the rounding mode [round away from **0**][6]. **f(x)** : Returns the factorial of the truncated absolute value of **x**. **perm(n, k)** : Returns the permutation of the truncated absolute value of **n** of the truncated absolute value of **k**, if **k \<= n**. If not, it returns **0**. **comb(n, k)** : Returns the combination of the truncated absolute value of **n** of the truncated absolute value of **k**, if **k \<= n**. If not, it returns **0**. **l2(x)** : Returns the logarithm base **2** of **x**. This is a transcendental function (see the *Transcendental Functions* subsection below). **l10(x)** : Returns the logarithm base **10** of **x**. This is a transcendental function (see the *Transcendental Functions* subsection below). **log(x, b)** : Returns the logarithm base **b** of **x**. This is a transcendental function (see the *Transcendental Functions* subsection below). **cbrt(x)** : Returns the cube root of **x**. **root(x, n)** : Calculates the truncated value of **n**, **r**, and returns the **r**th root of **x** to the current **scale**. If **r** is **0** or negative, this raises an error and causes bc(1) to reset (see the **RESET** section). It also raises an error and causes bc(1) to reset if **r** is even and **x** is negative. **gcd(a, b)** : Returns the greatest common divisor (factor) of the truncated absolute value of **a** and the truncated absolute value of **b**. **lcm(a, b)** : Returns the least common multiple of the truncated absolute value of **a** and the truncated absolute value of **b**. **pi(p)** : Returns **pi** to **p** decimal places. This is a transcendental function (see the *Transcendental Functions* subsection below). **t(x)** : Returns the tangent of **x**, which is assumed to be in radians. This is a transcendental function (see the *Transcendental Functions* subsection below). **a2(y, x)** : Returns the arctangent of **y/x**, in radians. If both **y** and **x** are equal to **0**, it raises an error and causes bc(1) to reset (see the **RESET** section). Otherwise, if **x** is greater than **0**, it returns **a(y/x)**. If **x** is less than **0**, and **y** is greater than or equal to **0**, it returns **a(y/x)+pi**. If **x** is less than **0**, and **y** is less than **0**, it returns **a(y/x)-pi**. If **x** is equal to **0**, and **y** is greater than **0**, it returns **pi/2**. If **x** is equal to **0**, and **y** is less than **0**, it returns **-pi/2**. This function is the same as the **atan2()** function in many programming languages. This is a transcendental function (see the *Transcendental Functions* subsection below). **sin(x)** : Returns the sine of **x**, which is assumed to be in radians. This is an alias of **s(x)**. This is a transcendental function (see the *Transcendental Functions* subsection below). **cos(x)** : Returns the cosine of **x**, which is assumed to be in radians. This is an alias of **c(x)**. This is a transcendental function (see the *Transcendental Functions* subsection below). **tan(x)** : Returns the tangent of **x**, which is assumed to be in radians. If **x** is equal to **1** or **-1**, this raises an error and causes bc(1) to reset (see the **RESET** section). This is an alias of **t(x)**. This is a transcendental function (see the *Transcendental Functions* subsection below). **atan(x)** : Returns the arctangent of **x**, in radians. This is an alias of **a(x)**. This is a transcendental function (see the *Transcendental Functions* subsection below). **atan2(y, x)** : Returns the arctangent of **y/x**, in radians. If both **y** and **x** are equal to **0**, it raises an error and causes bc(1) to reset (see the **RESET** section). Otherwise, if **x** is greater than **0**, it returns **a(y/x)**. If **x** is less than **0**, and **y** is greater than or equal to **0**, it returns **a(y/x)+pi**. If **x** is less than **0**, and **y** is less than **0**, it returns **a(y/x)-pi**. If **x** is equal to **0**, and **y** is greater than **0**, it returns **pi/2**. If **x** is equal to **0**, and **y** is less than **0**, it returns **-pi/2**. This function is the same as the **atan2()** function in many programming languages. This is an alias of **a2(y, x)**. This is a transcendental function (see the *Transcendental Functions* subsection below). **r2d(x)** : Converts **x** from radians to degrees and returns the result. This is a transcendental function (see the *Transcendental Functions* subsection below). **d2r(x)** : Converts **x** from degrees to radians and returns the result. This is a transcendental function (see the *Transcendental Functions* subsection below). **frand(p)** : Generates a pseudo-random number between **0** (inclusive) and **1** (exclusive) with the number of decimal digits after the decimal point equal to the truncated absolute value of **p**. If **p** is not **0**, then calling this function will change the value of **seed**. If **p** is **0**, then **0** is returned, and **seed** is *not* changed. **ifrand(i, p)** : Generates a pseudo-random number that is between **0** (inclusive) and the truncated absolute value of **i** (exclusive) with the number of decimal digits after the decimal point equal to the truncated absolute value of **p**. If the absolute value of **i** is greater than or equal to **2**, and **p** is not **0**, then calling this function will change the value of **seed**; otherwise, **0** is returned and **seed** is not changed. **srand(x)** : Returns **x** with its sign flipped with probability **0.5**. In other words, it randomizes the sign of **x**. **brand()** : Returns a random boolean value (either **0** or **1**). **band(a, b)** : Takes the truncated absolute value of both **a** and **b** and calculates and returns the result of the bitwise **and** operation between them. If you want to use signed two's complement arguments, use **s2u(x)** to convert. **bor(a, b)** : Takes the truncated absolute value of both **a** and **b** and calculates and returns the result of the bitwise **or** operation between them. If you want to use signed two's complement arguments, use **s2u(x)** to convert. **bxor(a, b)** : Takes the truncated absolute value of both **a** and **b** and calculates and returns the result of the bitwise **xor** operation between them. If you want to use signed two's complement arguments, use **s2u(x)** to convert. **bshl(a, b)** : Takes the truncated absolute value of both **a** and **b** and calculates and returns the result of **a** bit-shifted left by **b** places. If you want to use signed two's complement arguments, use **s2u(x)** to convert. **bshr(a, b)** : Takes the truncated absolute value of both **a** and **b** and calculates and returns the truncated result of **a** bit-shifted right by **b** places. If you want to use signed two's complement arguments, use **s2u(x)** to convert. **bnotn(x, n)** : Takes the truncated absolute value of **x** and does a bitwise not as though it has the same number of bytes as the truncated absolute value of **n**. If you want to a use signed two's complement argument, use **s2u(x)** to convert. **bnot8(x)** : Does a bitwise not of the truncated absolute value of **x** as though it has **8** binary digits (1 unsigned byte). If you want to a use signed two's complement argument, use **s2u(x)** to convert. **bnot16(x)** : Does a bitwise not of the truncated absolute value of **x** as though it has **16** binary digits (2 unsigned bytes). If you want to a use signed two's complement argument, use **s2u(x)** to convert. **bnot32(x)** : Does a bitwise not of the truncated absolute value of **x** as though it has **32** binary digits (4 unsigned bytes). If you want to a use signed two's complement argument, use **s2u(x)** to convert. **bnot64(x)** : Does a bitwise not of the truncated absolute value of **x** as though it has **64** binary digits (8 unsigned bytes). If you want to a use signed two's complement argument, use **s2u(x)** to convert. **bnot(x)** : Does a bitwise not of the truncated absolute value of **x** as though it has the minimum number of power of two unsigned bytes. If you want to a use signed two's complement argument, use **s2u(x)** to convert. **brevn(x, n)** : Runs a bit reversal on the truncated absolute value of **x** as though it has the same number of 8-bit bytes as the truncated absolute value of **n**. If you want to a use signed two's complement argument, use **s2u(x)** to convert. **brev8(x)** : Runs a bit reversal on the truncated absolute value of **x** as though it has 8 binary digits (1 unsigned byte). If you want to a use signed two's complement argument, use **s2u(x)** to convert. **brev16(x)** : Runs a bit reversal on the truncated absolute value of **x** as though it has 16 binary digits (2 unsigned bytes). If you want to a use signed two's complement argument, use **s2u(x)** to convert. **brev32(x)** : Runs a bit reversal on the truncated absolute value of **x** as though it has 32 binary digits (4 unsigned bytes). If you want to a use signed two's complement argument, use **s2u(x)** to convert. **brev64(x)** : Runs a bit reversal on the truncated absolute value of **x** as though it has 64 binary digits (8 unsigned bytes). If you want to a use signed two's complement argument, use **s2u(x)** to convert. **brev(x)** : Runs a bit reversal on the truncated absolute value of **x** as though it has the minimum number of power of two unsigned bytes. If you want to a use signed two's complement argument, use **s2u(x)** to convert. **broln(x, p, n)** : Does a left bitwise rotatation of the truncated absolute value of **x**, as though it has the same number of unsigned 8-bit bytes as the truncated absolute value of **n**, by the number of places equal to the truncated absolute value of **p** modded by the **2** to the power of the number of binary digits in **n** 8-bit bytes. If you want to a use signed two's complement argument, use **s2u(x)** to convert. **brol8(x, p)** : Does a left bitwise rotatation of the truncated absolute value of **x**, as though it has **8** binary digits (**1** unsigned byte), by the number of places equal to the truncated absolute value of **p** modded by **2** to the power of **8**. If you want to a use signed two's complement argument, use **s2u(x)** to convert. **brol16(x, p)** : Does a left bitwise rotatation of the truncated absolute value of **x**, as though it has **16** binary digits (**2** unsigned bytes), by the number of places equal to the truncated absolute value of **p** modded by **2** to the power of **16**. If you want to a use signed two's complement argument, use **s2u(x)** to convert. **brol32(x, p)** : Does a left bitwise rotatation of the truncated absolute value of **x**, as though it has **32** binary digits (**2** unsigned bytes), by the number of places equal to the truncated absolute value of **p** modded by **2** to the power of **32**. If you want to a use signed two's complement argument, use **s2u(x)** to convert. **brol64(x, p)** : Does a left bitwise rotatation of the truncated absolute value of **x**, as though it has **64** binary digits (**2** unsigned bytes), by the number of places equal to the truncated absolute value of **p** modded by **2** to the power of **64**. If you want to a use signed two's complement argument, use **s2u(x)** to convert. **brol(x, p)** : Does a left bitwise rotatation of the truncated absolute value of **x**, as though it has the minimum number of power of two unsigned 8-bit bytes, by the number of places equal to the truncated absolute value of **p** modded by 2 to the power of the number of binary digits in the minimum number of 8-bit bytes. If you want to a use signed two's complement argument, use **s2u(x)** to convert. **brorn(x, p, n)** : Does a right bitwise rotatation of the truncated absolute value of **x**, as though it has the same number of unsigned 8-bit bytes as the truncated absolute value of **n**, by the number of places equal to the truncated absolute value of **p** modded by the **2** to the power of the number of binary digits in **n** 8-bit bytes. If you want to a use signed two's complement argument, use **s2u(x)** to convert. **bror8(x, p)** : Does a right bitwise rotatation of the truncated absolute value of **x**, as though it has **8** binary digits (**1** unsigned byte), by the number of places equal to the truncated absolute value of **p** modded by **2** to the power of **8**. If you want to a use signed two's complement argument, use **s2u(x)** to convert. **bror16(x, p)** : Does a right bitwise rotatation of the truncated absolute value of **x**, as though it has **16** binary digits (**2** unsigned bytes), by the number of places equal to the truncated absolute value of **p** modded by **2** to the power of **16**. If you want to a use signed two's complement argument, use **s2u(x)** to convert. **bror32(x, p)** : Does a right bitwise rotatation of the truncated absolute value of **x**, as though it has **32** binary digits (**2** unsigned bytes), by the number of places equal to the truncated absolute value of **p** modded by **2** to the power of **32**. If you want to a use signed two's complement argument, use **s2u(x)** to convert. **bror64(x, p)** : Does a right bitwise rotatation of the truncated absolute value of **x**, as though it has **64** binary digits (**2** unsigned bytes), by the number of places equal to the truncated absolute value of **p** modded by **2** to the power of **64**. If you want to a use signed two's complement argument, use **s2u(x)** to convert. **bror(x, p)** : Does a right bitwise rotatation of the truncated absolute value of **x**, as though it has the minimum number of power of two unsigned 8-bit bytes, by the number of places equal to the truncated absolute value of **p** modded by 2 to the power of the number of binary digits in the minimum number of 8-bit bytes. If you want to a use signed two's complement argument, use **s2u(x)** to convert. **bmodn(x, n)** : Returns the modulus of the truncated absolute value of **x** by **2** to the power of the multiplication of the truncated absolute value of **n** and **8**. If you want to a use signed two's complement argument, use **s2u(x)** to convert. **bmod8(x, n)** : Returns the modulus of the truncated absolute value of **x** by **2** to the power of **8**. If you want to a use signed two's complement argument, use **s2u(x)** to convert. **bmod16(x, n)** : Returns the modulus of the truncated absolute value of **x** by **2** to the power of **16**. If you want to a use signed two's complement argument, use **s2u(x)** to convert. **bmod32(x, n)** : Returns the modulus of the truncated absolute value of **x** by **2** to the power of **32**. If you want to a use signed two's complement argument, use **s2u(x)** to convert. **bmod64(x, n)** : Returns the modulus of the truncated absolute value of **x** by **2** to the power of **64**. If you want to a use signed two's complement argument, use **s2u(x)** to convert. **bunrev(t)** : Assumes **t** is a bitwise-reversed number with an extra set bit one place more significant than the real most significant bit (which was the least significant bit in the original number). This number is reversed and returned without the extra set bit. This function is used to implement other bitwise functions; it is not meant to be used by users, but it can be. **plz(x)** : If **x** is not equal to **0** and greater that **-1** and less than **1**, it is printed with a leading zero, regardless of the use of the **-z** option (see the **OPTIONS** section) and without a trailing newline. Otherwise, **x** is printed normally, without a trailing newline. **plznl(x)** : If **x** is not equal to **0** and greater that **-1** and less than **1**, it is printed with a leading zero, regardless of the use of the **-z** option (see the **OPTIONS** section) and with a trailing newline. Otherwise, **x** is printed normally, with a trailing newline. **pnlz(x)** : If **x** is not equal to **0** and greater that **-1** and less than **1**, it is printed without a leading zero, regardless of the use of the **-z** option (see the **OPTIONS** section) and without a trailing newline. Otherwise, **x** is printed normally, without a trailing newline. **pnlznl(x)** : If **x** is not equal to **0** and greater that **-1** and less than **1**, it is printed without a leading zero, regardless of the use of the **-z** option (see the **OPTIONS** section) and with a trailing newline. Otherwise, **x** is printed normally, with a trailing newline. **ubytes(x)** : Returns the numbers of unsigned integer bytes required to hold the truncated absolute value of **x**. **sbytes(x)** : Returns the numbers of signed, two's-complement integer bytes required to hold the truncated value of **x**. **s2u(x)** : Returns **x** if it is non-negative. If it *is* negative, then it calculates what **x** would be as a 2's-complement signed integer and returns the non-negative integer that would have the same representation in binary. **s2un(x,n)** : Returns **x** if it is non-negative. If it *is* negative, then it calculates what **x** would be as a 2's-complement signed integer with **n** bytes and returns the non-negative integer that would have the same representation in binary. If **x** cannot fit into **n** 2's-complement signed bytes, it is truncated to fit. **hex(x)** : Outputs the hexadecimal (base **16**) representation of **x**. This is a **void** function (see the *Void Functions* subsection of the **FUNCTIONS** section). **binary(x)** : Outputs the binary (base **2**) representation of **x**. This is a **void** function (see the *Void Functions* subsection of the **FUNCTIONS** section). **output(x, b)** : Outputs the base **b** representation of **x**. This is a **void** function (see the *Void Functions* subsection of the **FUNCTIONS** section). **uint(x)** : Outputs the representation, in binary and hexadecimal, of **x** as an unsigned integer in as few power of two bytes as possible. Both outputs are split into bytes separated by spaces. If **x** is not an integer or is negative, an error message is printed instead, but bc(1) is not reset (see the **RESET** section). This is a **void** function (see the *Void Functions* subsection of the **FUNCTIONS** section). **int(x)** : Outputs the representation, in binary and hexadecimal, of **x** as a signed, two's-complement integer in as few power of two bytes as possible. Both outputs are split into bytes separated by spaces. If **x** is not an integer, an error message is printed instead, but bc(1) is not reset (see the **RESET** section). This is a **void** function (see the *Void Functions* subsection of the **FUNCTIONS** section). **uintn(x, n)** : Outputs the representation, in binary and hexadecimal, of **x** as an unsigned integer in **n** bytes. Both outputs are split into bytes separated by spaces. If **x** is not an integer, is negative, or cannot fit into **n** bytes, an error message is printed instead, but bc(1) is not reset (see the **RESET** section). This is a **void** function (see the *Void Functions* subsection of the **FUNCTIONS** section). **intn(x, n)** : Outputs the representation, in binary and hexadecimal, of **x** as a signed, two's-complement integer in **n** bytes. Both outputs are split into bytes separated by spaces. If **x** is not an integer or cannot fit into **n** bytes, an error message is printed instead, but bc(1) is not reset (see the **RESET** section). This is a **void** function (see the *Void Functions* subsection of the **FUNCTIONS** section). **uint8(x)** : Outputs the representation, in binary and hexadecimal, of **x** as an unsigned integer in **1** byte. Both outputs are split into bytes separated by spaces. If **x** is not an integer, is negative, or cannot fit into **1** byte, an error message is printed instead, but bc(1) is not reset (see the **RESET** section). This is a **void** function (see the *Void Functions* subsection of the **FUNCTIONS** section). **int8(x)** : Outputs the representation, in binary and hexadecimal, of **x** as a signed, two's-complement integer in **1** byte. Both outputs are split into bytes separated by spaces. If **x** is not an integer or cannot fit into **1** byte, an error message is printed instead, but bc(1) is not reset (see the **RESET** section). This is a **void** function (see the *Void Functions* subsection of the **FUNCTIONS** section). **uint16(x)** : Outputs the representation, in binary and hexadecimal, of **x** as an unsigned integer in **2** bytes. Both outputs are split into bytes separated by spaces. If **x** is not an integer, is negative, or cannot fit into **2** bytes, an error message is printed instead, but bc(1) is not reset (see the **RESET** section). This is a **void** function (see the *Void Functions* subsection of the **FUNCTIONS** section). **int16(x)** : Outputs the representation, in binary and hexadecimal, of **x** as a signed, two's-complement integer in **2** bytes. Both outputs are split into bytes separated by spaces. If **x** is not an integer or cannot fit into **2** bytes, an error message is printed instead, but bc(1) is not reset (see the **RESET** section). This is a **void** function (see the *Void Functions* subsection of the **FUNCTIONS** section). **uint32(x)** : Outputs the representation, in binary and hexadecimal, of **x** as an unsigned integer in **4** bytes. Both outputs are split into bytes separated by spaces. If **x** is not an integer, is negative, or cannot fit into **4** bytes, an error message is printed instead, but bc(1) is not reset (see the **RESET** section). This is a **void** function (see the *Void Functions* subsection of the **FUNCTIONS** section). **int32(x)** : Outputs the representation, in binary and hexadecimal, of **x** as a signed, two's-complement integer in **4** bytes. Both outputs are split into bytes separated by spaces. If **x** is not an integer or cannot fit into **4** bytes, an error message is printed instead, but bc(1) is not reset (see the **RESET** section). This is a **void** function (see the *Void Functions* subsection of the **FUNCTIONS** section). **uint64(x)** : Outputs the representation, in binary and hexadecimal, of **x** as an unsigned integer in **8** bytes. Both outputs are split into bytes separated by spaces. If **x** is not an integer, is negative, or cannot fit into **8** bytes, an error message is printed instead, but bc(1) is not reset (see the **RESET** section). This is a **void** function (see the *Void Functions* subsection of the **FUNCTIONS** section). **int64(x)** : Outputs the representation, in binary and hexadecimal, of **x** as a signed, two's-complement integer in **8** bytes. Both outputs are split into bytes separated by spaces. If **x** is not an integer or cannot fit into **8** bytes, an error message is printed instead, but bc(1) is not reset (see the **RESET** section). This is a **void** function (see the *Void Functions* subsection of the **FUNCTIONS** section). **hex_uint(x, n)** : Outputs the representation of the truncated absolute value of **x** as an unsigned integer in hexadecimal using **n** bytes. Not all of the value will be output if **n** is too small. This is a **void** function (see the *Void Functions* subsection of the **FUNCTIONS** section). **binary_uint(x, n)** : Outputs the representation of the truncated absolute value of **x** as an unsigned integer in binary using **n** bytes. Not all of the value will be output if **n** is too small. This is a **void** function (see the *Void Functions* subsection of the **FUNCTIONS** section). **output_uint(x, n)** : Outputs the representation of the truncated absolute value of **x** as an unsigned integer in the current **obase** (see the **SYNTAX** section) using **n** bytes. Not all of the value will be output if **n** is too small. This is a **void** function (see the *Void Functions* subsection of the **FUNCTIONS** section). **output_byte(x, i)** : Outputs byte **i** of the truncated absolute value of **x**, where **0** is the least significant byte and **number_of_bytes - 1** is the most significant byte. This is a **void** function (see the *Void Functions* subsection of the **FUNCTIONS** section). ## Transcendental Functions All transcendental functions can return slightly inaccurate results (up to 1 [ULP][4]). This is unavoidable, and [this article][5] explains why it is impossible and unnecessary to calculate exact results for the transcendental functions. Because of the possible inaccuracy, I recommend that users call those functions with the precision (**scale**) set to at least 1 higher than is necessary. If exact results are *absolutely* required, users can double the precision (**scale**) and then truncate. The transcendental functions in the standard math library are: * **s(x)** * **c(x)** * **a(x)** * **l(x)** * **e(x)** * **j(x, n)** The transcendental functions in the extended math library are: * **l2(x)** * **l10(x)** * **log(x, b)** * **pi(p)** * **t(x)** * **a2(y, x)** * **sin(x)** * **cos(x)** * **tan(x)** * **atan(x)** * **atan2(y, x)** * **r2d(x)** * **d2r(x)** # RESET When bc(1) encounters an error or a signal that it has a non-default handler for, it resets. This means that several things happen. First, any functions that are executing are stopped and popped off the stack. The behavior is not unlike that of exceptions in programming languages. Then the execution point is set so that any code waiting to execute (after all functions returned) is skipped. Thus, when bc(1) resets, it skips any remaining code waiting to be executed. Then, if it is interactive mode, and the error was not a fatal error (see the **EXIT STATUS** section), it asks for more input; otherwise, it exits with the appropriate return code. Note that this reset behavior is different from the GNU bc(1), which attempts to start executing the statement right after the one that caused an error. # PERFORMANCE Most bc(1) implementations use **char** types to calculate the value of **1** decimal digit at a time, but that can be slow. This bc(1) does something different. It uses large integers to calculate more than **1** decimal digit at a time. If built in a environment where **BC_LONG_BIT** (see the **LIMITS** section) is **64**, then each integer has **9** decimal digits. If built in an environment where **BC_LONG_BIT** is **32** then each integer has **4** decimal digits. This value (the number of decimal digits per large integer) is called **BC_BASE_DIGS**. The actual values of **BC_LONG_BIT** and **BC_BASE_DIGS** can be queried with the **limits** statement. In addition, this bc(1) uses an even larger integer for overflow checking. This integer type depends on the value of **BC_LONG_BIT**, but is always at least twice as large as the integer type used to store digits. # LIMITS The following are the limits on bc(1): **BC_LONG_BIT** : The number of bits in the **long** type in the environment where bc(1) was built. This determines how many decimal digits can be stored in a single large integer (see the **PERFORMANCE** section). **BC_BASE_DIGS** : The number of decimal digits per large integer (see the **PERFORMANCE** section). Depends on **BC_LONG_BIT**. **BC_BASE_POW** : The max decimal number that each large integer can store (see **BC_BASE_DIGS**) plus **1**. Depends on **BC_BASE_DIGS**. **BC_OVERFLOW_MAX** : The max number that the overflow type (see the **PERFORMANCE** section) can hold. Depends on **BC_LONG_BIT**. **BC_BASE_MAX** : The maximum output base. Set at **BC_BASE_POW**. **BC_DIM_MAX** : The maximum size of arrays. Set at **SIZE_MAX-1**. **BC_SCALE_MAX** : The maximum **scale**. Set at **BC_OVERFLOW_MAX-1**. **BC_STRING_MAX** : The maximum length of strings. Set at **BC_OVERFLOW_MAX-1**. **BC_NAME_MAX** : The maximum length of identifiers. Set at **BC_OVERFLOW_MAX-1**. **BC_NUM_MAX** : The maximum length of a number (in decimal digits), which includes digits after the decimal point. Set at **BC_OVERFLOW_MAX-1**. **BC_RAND_MAX** : The maximum integer (inclusive) returned by the **rand()** operand. Set at **2\^BC_LONG_BIT-1**. Exponent : The maximum allowable exponent (positive or negative). Set at **BC_OVERFLOW_MAX**. Number of vars : The maximum number of vars/arrays. Set at **SIZE_MAX-1**. The actual values can be queried with the **limits** statement. These limits are meant to be effectively non-existent; the limits are so large (at least on 64-bit machines) that there should not be any point at which they become a problem. In fact, memory should be exhausted before these limits should be hit. # ENVIRONMENT VARIABLES bc(1) recognizes the following environment variables: **POSIXLY_CORRECT** : If this variable exists (no matter the contents), bc(1) behaves as if the **-s** option was given. **BC_ENV_ARGS** : This is another way to give command-line arguments to bc(1). They should be in the same format as all other command-line arguments. These are always processed first, so any files given in **BC_ENV_ARGS** will be processed before arguments and files given on the command-line. This gives the user the ability to set up "standard" options and files to be used at every invocation. The most useful thing for such files to contain would be useful functions that the user might want every time bc(1) runs. The code that parses **BC_ENV_ARGS** will correctly handle quoted arguments, but it does not understand escape sequences. For example, the string **"/home/gavin/some bc file.bc"** will be correctly parsed, but the string **"/home/gavin/some \"bc\" file.bc"** will include the backslashes. The quote parsing will handle either kind of quotes, **'** or **"**. Thus, if you have a file with any number of single quotes in the name, you can use double quotes as the outside quotes, as in **"some 'bc' file.bc"**, and vice versa if you have a file with double quotes. However, handling a file with both kinds of quotes in **BC_ENV_ARGS** is not supported due to the complexity of the parsing, though such files are still supported on the command-line where the parsing is done by the shell. **BC_LINE_LENGTH** : If this environment variable exists and contains an integer that is greater than **1** and is less than **UINT16_MAX** (**2\^16-1**), bc(1) will output lines to that length, including the backslash (**\\**). The default line length is **70**. The special value of **0** will disable line length checking and print numbers without regard to line length and without backslashes and newlines. **BC_BANNER** : If this environment variable exists and contains an integer, then a non-zero value activates the copyright banner when bc(1) is in interactive mode, while zero deactivates it. If bc(1) is not in interactive mode (see the **INTERACTIVE MODE** section), then this environment variable has no effect because bc(1) does not print the banner when not in interactive mode. This environment variable overrides the default, which can be queried with the **-h** or **-\-help** options. **BC_SIGINT_RESET** : If bc(1) is not in interactive mode (see the **INTERACTIVE MODE** section), then this environment variable has no effect because bc(1) exits on **SIGINT** when not in interactive mode. However, when bc(1) is in interactive mode, then if this environment variable exists and contains an integer, a non-zero value makes bc(1) reset on **SIGINT**, rather than exit, and zero makes bc(1) exit. If this environment variable exists and is *not* an integer, then bc(1) will exit on **SIGINT**. This environment variable overrides the default, which can be queried with the **-h** or **-\-help** options. **BC_TTY_MODE** : If TTY mode is *not* available (see the **TTY MODE** section), then this environment variable has no effect. However, when TTY mode is available, then if this environment variable exists and contains an integer, then a non-zero value makes bc(1) use TTY mode, and zero makes bc(1) not use TTY mode. This environment variable overrides the default, which can be queried with the **-h** or **-\-help** options. **BC_PROMPT** : If TTY mode is *not* available (see the **TTY MODE** section), then this environment variable has no effect. However, when TTY mode is available, then if this environment variable exists and contains an integer, a non-zero value makes bc(1) use a prompt, and zero or a non-integer makes bc(1) not use a prompt. If this environment variable does not exist and **BC_TTY_MODE** does, then the value of the **BC_TTY_MODE** environment variable is used. This environment variable and the **BC_TTY_MODE** environment variable override the default, which can be queried with the **-h** or **-\-help** options. +**BC_EXPR_EXIT** + +: If any expressions or expression files are given on the command-line with + **-e**, **-\-expression**, **-f**, or **-\-file**, then if this environment + variable exists and contains an integer, a non-zero value makes bc(1) exit + after executing the expressions and expression files, and a non-zero value + makes bc(1) not exit. + + This environment variable overrides the default, which can be queried with + the **-h** or **-\-help** options. + # EXIT STATUS bc(1) returns the following exit statuses: **0** : No error. **1** : A math error occurred. This follows standard practice of using **1** for expected errors, since math errors will happen in the process of normal execution. Math errors include divide by **0**, taking the square root of a negative number, using a negative number as a bound for the pseudo-random number generator, attempting to convert a negative number to a hardware integer, overflow when converting a number to a hardware integer, overflow when calculating the size of a number, and attempting to use a non-integer where an integer is required. Converting to a hardware integer happens for the second operand of the power (**\^**), places (**\@**), left shift (**\<\<**), and right shift (**\>\>**) operators and their corresponding assignment operators. **2** : A parse error occurred. Parse errors include unexpected **EOF**, using an invalid character, failing to find the end of a string or comment, using a token where it is invalid, giving an invalid expression, giving an invalid print statement, giving an invalid function definition, attempting to assign to an expression that is not a named expression (see the *Named Expressions* subsection of the **SYNTAX** section), giving an invalid **auto** list, having a duplicate **auto**/function parameter, failing to find the end of a code block, attempting to return a value from a **void** function, attempting to use a variable as a reference, and using any extensions when the option **-s** or any equivalents were given. **3** : A runtime error occurred. Runtime errors include assigning an invalid number to any global (**ibase**, **obase**, or **scale**), giving a bad expression to a **read()** call, calling **read()** inside of a **read()** call, type errors, passing the wrong number of arguments to functions, attempting to call an undefined function, and attempting to use a **void** function call as a value in an expression. **4** : A fatal error occurred. Fatal errors include memory allocation errors, I/O errors, failing to open files, attempting to use files that do not have only ASCII characters (bc(1) only accepts ASCII characters), attempting to open a directory as a file, and giving invalid command-line options. The exit status **4** is special; when a fatal error occurs, bc(1) always exits and returns **4**, no matter what mode bc(1) is in. The other statuses will only be returned when bc(1) is not in interactive mode (see the **INTERACTIVE MODE** section), since bc(1) resets its state (see the **RESET** section) and accepts more input when one of those errors occurs in interactive mode. This is also the case when interactive mode is forced by the **-i** flag or **-\-interactive** option. These exit statuses allow bc(1) to be used in shell scripting with error checking, and its normal behavior can be forced by using the **-i** flag or **-\-interactive** option. # INTERACTIVE MODE Per the [standard][1], bc(1) has an interactive mode and a non-interactive mode. Interactive mode is turned on automatically when both **stdin** and **stdout** are hooked to a terminal, but the **-i** flag and **-\-interactive** option can turn it on in other situations. In interactive mode, bc(1) attempts to recover from errors (see the **RESET** section), and in normal execution, flushes **stdout** as soon as execution is done for the current input. bc(1) may also reset on **SIGINT** instead of exit, depending on the contents of, or default for, the **BC_SIGINT_RESET** environment variable (see the **ENVIRONMENT VARIABLES** section). # TTY MODE If **stdin**, **stdout**, and **stderr** are all connected to a TTY, then "TTY mode" is considered to be available, and thus, bc(1) can turn on TTY mode, subject to some settings. If there is the environment variable **BC_TTY_MODE** in the environment (see the **ENVIRONMENT VARIABLES** section), then if that environment variable contains a non-zero integer, bc(1) will turn on TTY mode when **stdin**, **stdout**, and **stderr** are all connected to a TTY. If the **BC_TTY_MODE** environment variable exists but is *not* a non-zero integer, then bc(1) will not turn TTY mode on. If the environment variable **BC_TTY_MODE** does *not* exist, the default setting is used. The default setting can be queried with the **-h** or **-\-help** options. TTY mode is different from interactive mode because interactive mode is required in the [bc(1) specification][1], and interactive mode requires only **stdin** and **stdout** to be connected to a terminal. ## Prompt If TTY mode is available, then a prompt can be enabled. Like TTY mode itself, it can be turned on or off with an environment variable: **BC_PROMPT** (see the **ENVIRONMENT VARIABLES** section). If the environment variable **BC_PROMPT** exists and is a non-zero integer, then the prompt is turned on when **stdin**, **stdout**, and **stderr** are connected to a TTY and the **-P** and **-\-no-prompt** options were not used. The read prompt will be turned on under the same conditions, except that the **-R** and **-\-no-read-prompt** options must also not be used. However, if **BC_PROMPT** does not exist, the prompt can be enabled or disabled with the **BC_TTY_MODE** environment variable, the **-P** and **-\-no-prompt** options, and the **-R** and **-\-no-read-prompt** options. See the **ENVIRONMENT VARIABLES** and **OPTIONS** sections for more details. # SIGNAL HANDLING Sending a **SIGINT** will cause bc(1) to do one of two things. If bc(1) is not in interactive mode (see the **INTERACTIVE MODE** section), or the **BC_SIGINT_RESET** environment variable (see the **ENVIRONMENT VARIABLES** section), or its default, is either not an integer or it is zero, bc(1) will exit. However, if bc(1) is in interactive mode, and the **BC_SIGINT_RESET** or its default is an integer and non-zero, then bc(1) will stop executing the current input and reset (see the **RESET** section) upon receiving a **SIGINT**. Note that "current input" can mean one of two things. If bc(1) is processing input from **stdin** in interactive mode, it will ask for more input. If bc(1) is processing input from a file in interactive mode, it will stop processing the file and start processing the next file, if one exists, or ask for input from **stdin** if no other file exists. This means that if a **SIGINT** is sent to bc(1) as it is executing a file, it can seem as though bc(1) did not respond to the signal since it will immediately start executing the next file. This is by design; most files that users execute when interacting with bc(1) have function definitions, which are quick to parse. If a file takes a long time to execute, there may be a bug in that file. The rest of the files could still be executed without problem, allowing the user to continue. **SIGTERM** and **SIGQUIT** cause bc(1) to clean up and exit, and it uses the default handler for all other signals. # LOCALES This bc(1) ships with support for adding error messages for different locales and thus, supports **LC_MESSAGES**. # SEE ALSO dc(1) # STANDARDS bc(1) is compliant with the [IEEE Std 1003.1-2017 (“POSIX.1-2017”)][1] specification. The flags **-efghiqsvVw**, all long options, and the extensions noted above are extensions to that specification. Note that the specification explicitly says that bc(1) only accepts numbers that use a period (**.**) as a radix point, regardless of the value of **LC_NUMERIC**. This bc(1) supports error messages for different locales, and thus, it supports **LC_MESSAGES**. # BUGS None are known. Report bugs at https://git.yzena.com/gavin/bc. # AUTHORS Gavin D. Howard and contributors. [1]: https://pubs.opengroup.org/onlinepubs/9699919799/utilities/bc.html [2]: https://www.gnu.org/software/bc/ [3]: https://en.wikipedia.org/wiki/Rounding#Round_half_away_from_zero [4]: https://en.wikipedia.org/wiki/Unit_in_the_last_place [5]: https://people.eecs.berkeley.edu/~wkahan/LOG10HAF.TXT [6]: https://en.wikipedia.org/wiki/Rounding#Rounding_away_from_zero diff --git a/contrib/bc/manuals/bc/HN.1 b/contrib/bc/manuals/bc/HN.1 index 4773ff77efea..0687cb263b6e 100644 --- a/contrib/bc/manuals/bc/HN.1 +++ b/contrib/bc/manuals/bc/HN.1 @@ -1,2748 +1,2761 @@ .\" .\" SPDX-License-Identifier: BSD-2-Clause .\" .\" Copyright (c) 2018-2021 Gavin D. Howard and contributors. .\" .\" Redistribution and use in source and binary forms, with or without .\" modification, are permitted provided that the following conditions are met: .\" .\" * Redistributions of source code must retain the above copyright notice, .\" this list of conditions and the following disclaimer. .\" .\" * Redistributions in binary form must reproduce the above copyright notice, .\" this list of conditions and the following disclaimer in the documentation .\" and/or other materials provided with the distribution. .\" .\" THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" .\" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE .\" IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE .\" ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE .\" LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR .\" CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF .\" SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS .\" INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN .\" CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) .\" ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE .\" POSSIBILITY OF SUCH DAMAGE. .\" .TH "BC" "1" "June 2021" "Gavin D. Howard" "General Commands Manual" .SH NAME .PP bc - arbitrary-precision decimal arithmetic language and calculator .SH SYNOPSIS .PP \f[B]bc\f[R] [\f[B]-ghilPqRsvVw\f[R]] [\f[B]--global-stacks\f[R]] [\f[B]--help\f[R]] [\f[B]--interactive\f[R]] [\f[B]--mathlib\f[R]] [\f[B]--no-prompt\f[R]] [\f[B]--no-read-prompt\f[R]] [\f[B]--quiet\f[R]] [\f[B]--standard\f[R]] [\f[B]--warn\f[R]] [\f[B]--version\f[R]] [\f[B]-e\f[R] \f[I]expr\f[R]] [\f[B]--expression\f[R]=\f[I]expr\f[R]\&...] [\f[B]-f\f[R] \f[I]file\f[R]\&...] [\f[B]--file\f[R]=\f[I]file\f[R]\&...] [\f[I]file\f[R]\&...] .SH DESCRIPTION .PP bc(1) is an interactive processor for a language first standardized in 1991 by POSIX. (The current standard is here (https://pubs.opengroup.org/onlinepubs/9699919799/utilities/bc.html).) The language provides unlimited precision decimal arithmetic and is somewhat C-like, but there are differences. Such differences will be noted in this document. .PP After parsing and handling options, this bc(1) reads any files given on the command line and executes them before reading from \f[B]stdin\f[R]. .PP This bc(1) is a drop-in replacement for \f[I]any\f[R] bc(1), including (and especially) the GNU bc(1). It also has many extensions and extra features beyond other implementations. .PP \f[B]Note\f[R]: If running this bc(1) on \f[I]any\f[R] script meant for another bc(1) gives a parse error, it is probably because a word this bc(1) reserves as a keyword is used as the name of a function, variable, or array. To fix that, use the command-line option \f[B]-r\f[R] \f[I]keyword\f[R], where \f[I]keyword\f[R] is the keyword that is used as a name in the script. For more information, see the \f[B]OPTIONS\f[R] section. .PP If parsing scripts meant for other bc(1) implementations still does not work, that is a bug and should be reported. See the \f[B]BUGS\f[R] section. .SH OPTIONS .PP The following are the options that bc(1) accepts. .TP \f[B]-g\f[R], \f[B]--global-stacks\f[R] Turns the globals \f[B]ibase\f[R], \f[B]obase\f[R], \f[B]scale\f[R], and \f[B]seed\f[R] into stacks. .RS .PP This has the effect that a copy of the current value of all four are pushed onto a stack for every function call, as well as popped when every function returns. This means that functions can assign to any and all of those globals without worrying that the change will affect other functions. Thus, a hypothetical function named \f[B]output(x,b)\f[R] that simply printed \f[B]x\f[R] in base \f[B]b\f[R] could be written like this: .IP .nf \f[C] define void output(x, b) { obase=b x } \f[R] .fi .PP instead of like this: .IP .nf \f[C] define void output(x, b) { auto c c=obase obase=b x obase=c } \f[R] .fi .PP This makes writing functions much easier. .PP (\f[B]Note\f[R]: the function \f[B]output(x,b)\f[R] exists in the extended math library. See the \f[B]LIBRARY\f[R] section.) .PP However, since using this flag means that functions cannot set \f[B]ibase\f[R], \f[B]obase\f[R], \f[B]scale\f[R], or \f[B]seed\f[R] globally, functions that are made to do so cannot work anymore. There are two possible use cases for that, and each has a solution. .PP First, if a function is called on startup to turn bc(1) into a number converter, it is possible to replace that capability with various shell aliases. Examples: .IP .nf \f[C] alias d2o=\[dq]bc -e ibase=A -e obase=8\[dq] alias h2b=\[dq]bc -e ibase=G -e obase=2\[dq] \f[R] .fi .PP Second, if the purpose of a function is to set \f[B]ibase\f[R], \f[B]obase\f[R], \f[B]scale\f[R], or \f[B]seed\f[R] globally for any other purpose, it could be split into one to four functions (based on how many globals it sets) and each of those functions could return the desired value for a global. .PP For functions that set \f[B]seed\f[R], the value assigned to \f[B]seed\f[R] is not propagated to parent functions. This means that the sequence of pseudo-random numbers that they see will not be the same sequence of pseudo-random numbers that any parent sees. This is only the case once \f[B]seed\f[R] has been set. .PP If a function desires to not affect the sequence of pseudo-random numbers of its parents, but wants to use the same \f[B]seed\f[R], it can use the following line: .IP .nf \f[C] seed = seed \f[R] .fi .PP If the behavior of this option is desired for every run of bc(1), then users could make sure to define \f[B]BC_ENV_ARGS\f[R] and include this option (see the \f[B]ENVIRONMENT VARIABLES\f[R] section for more details). .PP If \f[B]-s\f[R], \f[B]-w\f[R], or any equivalents are used, this option is ignored. .PP This is a \f[B]non-portable extension\f[R]. .RE .TP \f[B]-h\f[R], \f[B]--help\f[R] Prints a usage message and quits. .TP \f[B]-i\f[R], \f[B]--interactive\f[R] Forces interactive mode. (See the \f[B]INTERACTIVE MODE\f[R] section.) .RS .PP This is a \f[B]non-portable extension\f[R]. .RE .TP \f[B]-L\f[R], \f[B]--no-line-length\f[R] Disables line length checking and prints numbers without backslashes and newlines. In other words, this option sets \f[B]BC_LINE_LENGTH\f[R] to \f[B]0\f[R] (see the \f[B]ENVIRONMENT VARIABLES\f[R] section). .RS .PP This is a \f[B]non-portable extension\f[R]. .RE .TP \f[B]-l\f[R], \f[B]--mathlib\f[R] Sets \f[B]scale\f[R] (see the \f[B]SYNTAX\f[R] section) to \f[B]20\f[R] and loads the included math library and the extended math library before running any code, including any expressions or files specified on the command line. .RS .PP To learn what is in the libraries, see the \f[B]LIBRARY\f[R] section. .RE .TP \f[B]-P\f[R], \f[B]--no-prompt\f[R] Disables the prompt in TTY mode. (The prompt is only enabled in TTY mode. See the \f[B]TTY MODE\f[R] section.) This is mostly for those users that do not want a prompt or are not used to having them in bc(1). Most of those users would want to put this option in \f[B]BC_ENV_ARGS\f[R] (see the \f[B]ENVIRONMENT VARIABLES\f[R] section). .RS .PP These options override the \f[B]BC_PROMPT\f[R] and \f[B]BC_TTY_MODE\f[R] environment variables (see the \f[B]ENVIRONMENT VARIABLES\f[R] section). .PP This is a \f[B]non-portable extension\f[R]. .RE .TP \f[B]-R\f[R], \f[B]--no-read-prompt\f[R] Disables the read prompt in TTY mode. (The read prompt is only enabled in TTY mode. See the \f[B]TTY MODE\f[R] section.) This is mostly for those users that do not want a read prompt or are not used to having them in bc(1). Most of those users would want to put this option in \f[B]BC_ENV_ARGS\f[R] (see the \f[B]ENVIRONMENT VARIABLES\f[R] section). This option is also useful in hash bang lines of bc(1) scripts that prompt for user input. .RS .PP This option does not disable the regular prompt because the read prompt is only used when the \f[B]read()\f[R] built-in function is called. .PP These options \f[I]do\f[R] override the \f[B]BC_PROMPT\f[R] and \f[B]BC_TTY_MODE\f[R] environment variables (see the \f[B]ENVIRONMENT VARIABLES\f[R] section), but only for the read prompt. .PP This is a \f[B]non-portable extension\f[R]. .RE .TP \f[B]-r\f[R] \f[I]keyword\f[R], \f[B]--redefine\f[R]=\f[I]keyword\f[R] Redefines \f[I]keyword\f[R] in order to allow it to be used as a function, variable, or array name. This is useful when this bc(1) gives parse errors when parsing scripts meant for other bc(1) implementations. .RS .PP The keywords this bc(1) allows to be redefined are: .IP \[bu] 2 \f[B]abs\f[R] .IP \[bu] 2 \f[B]asciify\f[R] .IP \[bu] 2 \f[B]continue\f[R] .IP \[bu] 2 \f[B]divmod\f[R] .IP \[bu] 2 \f[B]else\f[R] .IP \[bu] 2 \f[B]halt\f[R] .IP \[bu] 2 \f[B]irand\f[R] .IP \[bu] 2 \f[B]last\f[R] .IP \[bu] 2 \f[B]limits\f[R] .IP \[bu] 2 \f[B]maxibase\f[R] .IP \[bu] 2 \f[B]maxobase\f[R] .IP \[bu] 2 \f[B]maxrand\f[R] .IP \[bu] 2 \f[B]maxscale\f[R] .IP \[bu] 2 \f[B]modexp\f[R] .IP \[bu] 2 \f[B]print\f[R] .IP \[bu] 2 \f[B]rand\f[R] .IP \[bu] 2 \f[B]read\f[R] .IP \[bu] 2 \f[B]seed\f[R] .IP \[bu] 2 \f[B]stream\f[R] .PP If any of those keywords are used as a function, variable, or array name in a script, use this option with the keyword as the argument. If multiple are used, use this option for all of them; it can be used multiple times. .PP Keywords are \f[I]not\f[R] redefined when parsing the builtin math library (see the \f[B]LIBRARY\f[R] section). .PP It is a fatal error to redefine keywords mandated by the POSIX standard. It is a fatal error to attempt to redefine words that this bc(1) does not reserve as keywords. .RE .TP \f[B]-q\f[R], \f[B]--quiet\f[R] This option is for compatibility with the GNU bc(1) (https://www.gnu.org/software/bc/); it is a no-op. Without this option, GNU bc(1) prints a copyright header. This bc(1) only prints the copyright header if one or more of the \f[B]-v\f[R], \f[B]-V\f[R], or \f[B]--version\f[R] options are given. .RS .PP This is a \f[B]non-portable extension\f[R]. .RE .TP \f[B]-s\f[R], \f[B]--standard\f[R] Process exactly the language defined by the standard (https://pubs.opengroup.org/onlinepubs/9699919799/utilities/bc.html) and error if any extensions are used. .RS .PP This is a \f[B]non-portable extension\f[R]. .RE .TP \f[B]-v\f[R], \f[B]-V\f[R], \f[B]--version\f[R] Print the version information (copyright header) and exit. .RS .PP This is a \f[B]non-portable extension\f[R]. .RE .TP \f[B]-w\f[R], \f[B]--warn\f[R] Like \f[B]-s\f[R] and \f[B]--standard\f[R], except that warnings (and not errors) are printed for non-standard extensions and execution continues normally. .RS .PP This is a \f[B]non-portable extension\f[R]. .RE .TP \f[B]-z\f[R], \f[B]--leading-zeroes\f[R] Makes bc(1) print all numbers greater than \f[B]-1\f[R] and less than \f[B]1\f[R], and not equal to \f[B]0\f[R], with a leading zero. .RS .PP This can be set for individual numbers with the \f[B]plz(x)\f[R], plznl(x)**, \f[B]pnlz(x)\f[R], and \f[B]pnlznl(x)\f[R] functions in the extended math library (see the \f[B]LIBRARY\f[R] section). .PP This is a \f[B]non-portable extension\f[R]. .RE .TP \f[B]-e\f[R] \f[I]expr\f[R], \f[B]--expression\f[R]=\f[I]expr\f[R] Evaluates \f[I]expr\f[R]. If multiple expressions are given, they are evaluated in order. If files are given as well (see below), the expressions and files are evaluated in the order given. This means that if a file is given before an expression, the file is read in and evaluated first. .RS .PP If this option is given on the command-line (i.e., not in \f[B]BC_ENV_ARGS\f[R], see the \f[B]ENVIRONMENT VARIABLES\f[R] section), then after processing all expressions and files, bc(1) will exit, unless \f[B]-\f[R] (\f[B]stdin\f[R]) was given as an argument at least once to \f[B]-f\f[R] or \f[B]--file\f[R], whether on the command-line or in \f[B]BC_ENV_ARGS\f[R]. However, if any other \f[B]-e\f[R], \f[B]--expression\f[R], \f[B]-f\f[R], or \f[B]--file\f[R] arguments are given after \f[B]-f-\f[R] or equivalent is given, bc(1) will give a fatal error and exit. .PP This is a \f[B]non-portable extension\f[R]. .RE .TP \f[B]-f\f[R] \f[I]file\f[R], \f[B]--file\f[R]=\f[I]file\f[R] Reads in \f[I]file\f[R] and evaluates it, line by line, as though it were read through \f[B]stdin\f[R]. If expressions are also given (see above), the expressions are evaluated in the order given. .RS .PP If this option is given on the command-line (i.e., not in \f[B]BC_ENV_ARGS\f[R], see the \f[B]ENVIRONMENT VARIABLES\f[R] section), then after processing all expressions and files, bc(1) will exit, unless \f[B]-\f[R] (\f[B]stdin\f[R]) was given as an argument at least once to \f[B]-f\f[R] or \f[B]--file\f[R]. However, if any other \f[B]-e\f[R], \f[B]--expression\f[R], \f[B]-f\f[R], or \f[B]--file\f[R] arguments are given after \f[B]-f-\f[R] or equivalent is given, bc(1) will give a fatal error and exit. .PP This is a \f[B]non-portable extension\f[R]. .RE .PP All long options are \f[B]non-portable extensions\f[R]. .SH STDIN .PP If no files or expressions are given by the \f[B]-f\f[R], \f[B]--file\f[R], \f[B]-e\f[R], or \f[B]--expression\f[R] options, then bc(1) read from \f[B]stdin\f[R]. .PP However, there are a few caveats to this. .PP First, \f[B]stdin\f[R] is evaluated a line at a time. The only exception to this is if the parse cannot complete. That means that starting a string without ending it or starting a function, \f[B]if\f[R] statement, or loop without ending it will also cause bc(1) to not execute. .PP Second, after an \f[B]if\f[R] statement, bc(1) doesn\[cq]t know if an \f[B]else\f[R] statement will follow, so it will not execute until it knows there will not be an \f[B]else\f[R] statement. .SH STDOUT .PP Any non-error output is written to \f[B]stdout\f[R]. In addition, if history (see the \f[B]HISTORY\f[R] section) and the prompt (see the \f[B]TTY MODE\f[R] section) are enabled, both are output to \f[B]stdout\f[R]. .PP \f[B]Note\f[R]: Unlike other bc(1) implementations, this bc(1) will issue a fatal error (see the \f[B]EXIT STATUS\f[R] section) if it cannot write to \f[B]stdout\f[R], so if \f[B]stdout\f[R] is closed, as in \f[B]bc >&-\f[R], it will quit with an error. This is done so that bc(1) can report problems when \f[B]stdout\f[R] is redirected to a file. .PP If there are scripts that depend on the behavior of other bc(1) implementations, it is recommended that those scripts be changed to redirect \f[B]stdout\f[R] to \f[B]/dev/null\f[R]. .SH STDERR .PP Any error output is written to \f[B]stderr\f[R]. .PP \f[B]Note\f[R]: Unlike other bc(1) implementations, this bc(1) will issue a fatal error (see the \f[B]EXIT STATUS\f[R] section) if it cannot write to \f[B]stderr\f[R], so if \f[B]stderr\f[R] is closed, as in \f[B]bc 2>&-\f[R], it will quit with an error. This is done so that bc(1) can exit with an error code when \f[B]stderr\f[R] is redirected to a file. .PP If there are scripts that depend on the behavior of other bc(1) implementations, it is recommended that those scripts be changed to redirect \f[B]stderr\f[R] to \f[B]/dev/null\f[R]. .SH SYNTAX .PP The syntax for bc(1) programs is mostly C-like, with some differences. This bc(1) follows the POSIX standard (https://pubs.opengroup.org/onlinepubs/9699919799/utilities/bc.html), which is a much more thorough resource for the language this bc(1) accepts. This section is meant to be a summary and a listing of all the extensions to the standard. .PP In the sections below, \f[B]E\f[R] means expression, \f[B]S\f[R] means statement, and \f[B]I\f[R] means identifier. .PP Identifiers (\f[B]I\f[R]) start with a lowercase letter and can be followed by any number (up to \f[B]BC_NAME_MAX-1\f[R]) of lowercase letters (\f[B]a-z\f[R]), digits (\f[B]0-9\f[R]), and underscores (\f[B]_\f[R]). The regex is \f[B][a-z][a-z0-9_]*\f[R]. Identifiers with more than one character (letter) are a \f[B]non-portable extension\f[R]. .PP \f[B]ibase\f[R] is a global variable determining how to interpret constant numbers. It is the \[lq]input\[rq] base, or the number base used for interpreting input numbers. \f[B]ibase\f[R] is initially \f[B]10\f[R]. If the \f[B]-s\f[R] (\f[B]--standard\f[R]) and \f[B]-w\f[R] (\f[B]--warn\f[R]) flags were not given on the command line, the max allowable value for \f[B]ibase\f[R] is \f[B]36\f[R]. Otherwise, it is \f[B]16\f[R]. The min allowable value for \f[B]ibase\f[R] is \f[B]2\f[R]. The max allowable value for \f[B]ibase\f[R] can be queried in bc(1) programs with the \f[B]maxibase()\f[R] built-in function. .PP \f[B]obase\f[R] is a global variable determining how to output results. It is the \[lq]output\[rq] base, or the number base used for outputting numbers. \f[B]obase\f[R] is initially \f[B]10\f[R]. The max allowable value for \f[B]obase\f[R] is \f[B]BC_BASE_MAX\f[R] and can be queried in bc(1) programs with the \f[B]maxobase()\f[R] built-in function. The min allowable value for \f[B]obase\f[R] is \f[B]0\f[R]. If \f[B]obase\f[R] is \f[B]0\f[R], values are output in scientific notation, and if \f[B]obase\f[R] is \f[B]1\f[R], values are output in engineering notation. Otherwise, values are output in the specified base. .PP Outputting in scientific and engineering notations are \f[B]non-portable extensions\f[R]. .PP The \f[I]scale\f[R] of an expression is the number of digits in the result of the expression right of the decimal point, and \f[B]scale\f[R] is a global variable that sets the precision of any operations, with exceptions. \f[B]scale\f[R] is initially \f[B]0\f[R]. \f[B]scale\f[R] cannot be negative. The max allowable value for \f[B]scale\f[R] is \f[B]BC_SCALE_MAX\f[R] and can be queried in bc(1) programs with the \f[B]maxscale()\f[R] built-in function. .PP bc(1) has both \f[I]global\f[R] variables and \f[I]local\f[R] variables. All \f[I]local\f[R] variables are local to the function; they are parameters or are introduced in the \f[B]auto\f[R] list of a function (see the \f[B]FUNCTIONS\f[R] section). If a variable is accessed which is not a parameter or in the \f[B]auto\f[R] list, it is assumed to be \f[I]global\f[R]. If a parent function has a \f[I]local\f[R] variable version of a variable that a child function considers \f[I]global\f[R], the value of that \f[I]global\f[R] variable in the child function is the value of the variable in the parent function, not the value of the actual \f[I]global\f[R] variable. .PP All of the above applies to arrays as well. .PP The value of a statement that is an expression (i.e., any of the named expressions or operands) is printed unless the lowest precedence operator is an assignment operator \f[I]and\f[R] the expression is notsurrounded by parentheses. .PP The value that is printed is also assigned to the special variable \f[B]last\f[R]. A single dot (\f[B].\f[R]) may also be used as a synonym for \f[B]last\f[R]. These are \f[B]non-portable extensions\f[R]. .PP Either semicolons or newlines may separate statements. .SS Comments .PP There are two kinds of comments: .IP "1." 3 Block comments are enclosed in \f[B]/*\f[R] and \f[B]*/\f[R]. .IP "2." 3 Line comments go from \f[B]#\f[R] until, and not including, the next newline. This is a \f[B]non-portable extension\f[R]. .SS Named Expressions .PP The following are named expressions in bc(1): .IP "1." 3 Variables: \f[B]I\f[R] .IP "2." 3 Array Elements: \f[B]I[E]\f[R] .IP "3." 3 \f[B]ibase\f[R] .IP "4." 3 \f[B]obase\f[R] .IP "5." 3 \f[B]scale\f[R] .IP "6." 3 \f[B]seed\f[R] .IP "7." 3 \f[B]last\f[R] or a single dot (\f[B].\f[R]) .PP Numbers 6 and 7 are \f[B]non-portable extensions\f[R]. .PP The meaning of \f[B]seed\f[R] is dependent on the current pseudo-random number generator but is guaranteed to not change except for new major versions. .PP The \f[I]scale\f[R] and sign of the value may be significant. .PP If a previously used \f[B]seed\f[R] value is assigned to \f[B]seed\f[R] and used again, the pseudo-random number generator is guaranteed to produce the same sequence of pseudo-random numbers as it did when the \f[B]seed\f[R] value was previously used. .PP The exact value assigned to \f[B]seed\f[R] is not guaranteed to be returned if \f[B]seed\f[R] is queried again immediately. However, if \f[B]seed\f[R] \f[I]does\f[R] return a different value, both values, when assigned to \f[B]seed\f[R], are guaranteed to produce the same sequence of pseudo-random numbers. This means that certain values assigned to \f[B]seed\f[R] will \f[I]not\f[R] produce unique sequences of pseudo-random numbers. The value of \f[B]seed\f[R] will change after any use of the \f[B]rand()\f[R] and \f[B]irand(E)\f[R] operands (see the \f[I]Operands\f[R] subsection below), except if the parameter passed to \f[B]irand(E)\f[R] is \f[B]0\f[R], \f[B]1\f[R], or negative. .PP There is no limit to the length (number of significant decimal digits) or \f[I]scale\f[R] of the value that can be assigned to \f[B]seed\f[R]. .PP Variables and arrays do not interfere; users can have arrays named the same as variables. This also applies to functions (see the \f[B]FUNCTIONS\f[R] section), so a user can have a variable, array, and function that all have the same name, and they will not shadow each other, whether inside of functions or not. .PP Named expressions are required as the operand of \f[B]increment\f[R]/\f[B]decrement\f[R] operators and as the left side of \f[B]assignment\f[R] operators (see the \f[I]Operators\f[R] subsection). .SS Operands .PP The following are valid operands in bc(1): .IP " 1." 4 Numbers (see the \f[I]Numbers\f[R] subsection below). .IP " 2." 4 Array indices (\f[B]I[E]\f[R]). .IP " 3." 4 \f[B](E)\f[R]: The value of \f[B]E\f[R] (used to change precedence). .IP " 4." 4 \f[B]sqrt(E)\f[R]: The square root of \f[B]E\f[R]. \f[B]E\f[R] must be non-negative. .IP " 5." 4 \f[B]length(E)\f[R]: The number of significant decimal digits in \f[B]E\f[R]. Returns \f[B]1\f[R] for \f[B]0\f[R] with no decimal places. If given a string, the length of the string is returned. Passing a string to \f[B]length(E)\f[R] is a \f[B]non-portable extension\f[R]. .IP " 6." 4 \f[B]length(I[])\f[R]: The number of elements in the array \f[B]I\f[R]. This is a \f[B]non-portable extension\f[R]. .IP " 7." 4 \f[B]scale(E)\f[R]: The \f[I]scale\f[R] of \f[B]E\f[R]. .IP " 8." 4 \f[B]abs(E)\f[R]: The absolute value of \f[B]E\f[R]. This is a \f[B]non-portable extension\f[R]. .IP " 9." 4 \f[B]modexp(E, E, E)\f[R]: Modular exponentiation, where the first expression is the base, the second is the exponent, and the third is the modulus. All three values must be integers. The second argument must be non-negative. The third argument must be non-zero. This is a \f[B]non-portable extension\f[R]. .IP "10." 4 \f[B]divmod(E, E, I[])\f[R]: Division and modulus in one operation. This is for optimization. The first expression is the dividend, and the second is the divisor, which must be non-zero. The return value is the quotient, and the modulus is stored in index \f[B]0\f[R] of the provided array (the last argument). This is a \f[B]non-portable extension\f[R]. .IP "11." 4 \f[B]asciify(E)\f[R]: If \f[B]E\f[R] is a string, returns a string that is the first letter of its argument. If it is a number, calculates the number mod \f[B]256\f[R] and returns that number as a one-character string. This is a \f[B]non-portable extension\f[R]. .IP "12." 4 \f[B]I()\f[R], \f[B]I(E)\f[R], \f[B]I(E, E)\f[R], and so on, where \f[B]I\f[R] is an identifier for a non-\f[B]void\f[R] function (see the \f[I]Void Functions\f[R] subsection of the \f[B]FUNCTIONS\f[R] section). The \f[B]E\f[R] argument(s) may also be arrays of the form \f[B]I[]\f[R], which will automatically be turned into array references (see the \f[I]Array References\f[R] subsection of the \f[B]FUNCTIONS\f[R] section) if the corresponding parameter in the function definition is an array reference. .IP "13." 4 \f[B]read()\f[R]: Reads a line from \f[B]stdin\f[R] and uses that as an expression. The result of that expression is the result of the \f[B]read()\f[R] operand. This is a \f[B]non-portable extension\f[R]. .IP "14." 4 \f[B]maxibase()\f[R]: The max allowable \f[B]ibase\f[R]. This is a \f[B]non-portable extension\f[R]. .IP "15." 4 \f[B]maxobase()\f[R]: The max allowable \f[B]obase\f[R]. This is a \f[B]non-portable extension\f[R]. .IP "16." 4 \f[B]maxscale()\f[R]: The max allowable \f[B]scale\f[R]. This is a \f[B]non-portable extension\f[R]. .IP "17." 4 \f[B]line_length()\f[R]: The line length set with \f[B]BC_LINE_LENGTH\f[R] (see the \f[B]ENVIRONMENT VARIABLES\f[R] section). This is a \f[B]non-portable extension\f[R]. .IP "18." 4 \f[B]global_stacks()\f[R]: \f[B]0\f[R] if global stacks are not enabled with the \f[B]-g\f[R] or \f[B]--global-stacks\f[R] options, non-zero otherwise. See the \f[B]OPTIONS\f[R] section. This is a \f[B]non-portable extension\f[R]. .IP "19." 4 \f[B]leading_zero()\f[R]: \f[B]0\f[R] if leading zeroes are not enabled with the \f[B]-z\f[R] or \f[B]\[en]leading-zeroes\f[R] options, non-zero otherwise. See the \f[B]OPTIONS\f[R] section. This is a \f[B]non-portable extension\f[R]. .IP "20." 4 \f[B]rand()\f[R]: A pseudo-random integer between \f[B]0\f[R] (inclusive) and \f[B]BC_RAND_MAX\f[R] (inclusive). Using this operand will change the value of \f[B]seed\f[R]. This is a \f[B]non-portable extension\f[R]. .IP "21." 4 \f[B]irand(E)\f[R]: A pseudo-random integer between \f[B]0\f[R] (inclusive) and the value of \f[B]E\f[R] (exclusive). If \f[B]E\f[R] is negative or is a non-integer (\f[B]E\f[R]\[cq]s \f[I]scale\f[R] is not \f[B]0\f[R]), an error is raised, and bc(1) resets (see the \f[B]RESET\f[R] section) while \f[B]seed\f[R] remains unchanged. If \f[B]E\f[R] is larger than \f[B]BC_RAND_MAX\f[R], the higher bound is honored by generating several pseudo-random integers, multiplying them by appropriate powers of \f[B]BC_RAND_MAX+1\f[R], and adding them together. Thus, the size of integer that can be generated with this operand is unbounded. Using this operand will change the value of \f[B]seed\f[R], unless the value of \f[B]E\f[R] is \f[B]0\f[R] or \f[B]1\f[R]. In that case, \f[B]0\f[R] is returned, and \f[B]seed\f[R] is \f[I]not\f[R] changed. This is a \f[B]non-portable extension\f[R]. .IP "22." 4 \f[B]maxrand()\f[R]: The max integer returned by \f[B]rand()\f[R]. This is a \f[B]non-portable extension\f[R]. .PP The integers generated by \f[B]rand()\f[R] and \f[B]irand(E)\f[R] are guaranteed to be as unbiased as possible, subject to the limitations of the pseudo-random number generator. .PP \f[B]Note\f[R]: The values returned by the pseudo-random number generator with \f[B]rand()\f[R] and \f[B]irand(E)\f[R] are guaranteed to \f[I]NOT\f[R] be cryptographically secure. This is a consequence of using a seeded pseudo-random number generator. However, they \f[I]are\f[R] guaranteed to be reproducible with identical \f[B]seed\f[R] values. This means that the pseudo-random values from bc(1) should only be used where a reproducible stream of pseudo-random numbers is \f[I]ESSENTIAL\f[R]. In any other case, use a non-seeded pseudo-random number generator. .SS Numbers .PP Numbers are strings made up of digits, uppercase letters, and at most \f[B]1\f[R] period for a radix. Numbers can have up to \f[B]BC_NUM_MAX\f[R] digits. Uppercase letters are equal to \f[B]9\f[R] + their position in the alphabet (i.e., \f[B]A\f[R] equals \f[B]10\f[R], or \f[B]9+1\f[R]). If a digit or letter makes no sense with the current value of \f[B]ibase\f[R], they are set to the value of the highest valid digit in \f[B]ibase\f[R]. .PP Single-character numbers (i.e., \f[B]A\f[R] alone) take the value that they would have if they were valid digits, regardless of the value of \f[B]ibase\f[R]. This means that \f[B]A\f[R] alone always equals decimal \f[B]10\f[R] and \f[B]Z\f[R] alone always equals decimal \f[B]35\f[R]. .PP In addition, bc(1) accepts numbers in scientific notation. These have the form \f[B]e\f[R]. The exponent (the portion after the \f[B]e\f[R]) must be an integer. An example is \f[B]1.89237e9\f[R], which is equal to \f[B]1892370000\f[R]. Negative exponents are also allowed, so \f[B]4.2890e-3\f[R] is equal to \f[B]0.0042890\f[R]. .PP Using scientific notation is an error or warning if the \f[B]-s\f[R] or \f[B]-w\f[R], respectively, command-line options (or equivalents) are given. .PP \f[B]WARNING\f[R]: Both the number and the exponent in scientific notation are interpreted according to the current \f[B]ibase\f[R], but the number is still multiplied by \f[B]10\[ha]exponent\f[R] regardless of the current \f[B]ibase\f[R]. For example, if \f[B]ibase\f[R] is \f[B]16\f[R] and bc(1) is given the number string \f[B]FFeA\f[R], the resulting decimal number will be \f[B]2550000000000\f[R], and if bc(1) is given the number string \f[B]10e-4\f[R], the resulting decimal number will be \f[B]0.0016\f[R]. .PP Accepting input as scientific notation is a \f[B]non-portable extension\f[R]. .SS Operators .PP The following arithmetic and logical operators can be used. They are listed in order of decreasing precedence. Operators in the same group have the same precedence. .TP \f[B]++\f[R] \f[B]--\f[R] Type: Prefix and Postfix .RS .PP Associativity: None .PP Description: \f[B]increment\f[R], \f[B]decrement\f[R] .RE .TP \f[B]-\f[R] \f[B]!\f[R] Type: Prefix .RS .PP Associativity: None .PP Description: \f[B]negation\f[R], \f[B]boolean not\f[R] .RE .TP \f[B]$\f[R] Type: Postfix .RS .PP Associativity: None .PP Description: \f[B]truncation\f[R] .RE .TP \f[B]\[at]\f[R] Type: Binary .RS .PP Associativity: Right .PP Description: \f[B]set precision\f[R] .RE .TP \f[B]\[ha]\f[R] Type: Binary .RS .PP Associativity: Right .PP Description: \f[B]power\f[R] .RE .TP \f[B]*\f[R] \f[B]/\f[R] \f[B]%\f[R] Type: Binary .RS .PP Associativity: Left .PP Description: \f[B]multiply\f[R], \f[B]divide\f[R], \f[B]modulus\f[R] .RE .TP \f[B]+\f[R] \f[B]-\f[R] Type: Binary .RS .PP Associativity: Left .PP Description: \f[B]add\f[R], \f[B]subtract\f[R] .RE .TP \f[B]<<\f[R] \f[B]>>\f[R] Type: Binary .RS .PP Associativity: Left .PP Description: \f[B]shift left\f[R], \f[B]shift right\f[R] .RE .TP \f[B]=\f[R] \f[B]<<=\f[R] \f[B]>>=\f[R] \f[B]+=\f[R] \f[B]-=\f[R] \f[B]*=\f[R] \f[B]/=\f[R] \f[B]%=\f[R] \f[B]\[ha]=\f[R] \f[B]\[at]=\f[R] Type: Binary .RS .PP Associativity: Right .PP Description: \f[B]assignment\f[R] .RE .TP \f[B]==\f[R] \f[B]<=\f[R] \f[B]>=\f[R] \f[B]!=\f[R] \f[B]<\f[R] \f[B]>\f[R] Type: Binary .RS .PP Associativity: Left .PP Description: \f[B]relational\f[R] .RE .TP \f[B]&&\f[R] Type: Binary .RS .PP Associativity: Left .PP Description: \f[B]boolean and\f[R] .RE .TP \f[B]||\f[R] Type: Binary .RS .PP Associativity: Left .PP Description: \f[B]boolean or\f[R] .RE .PP The operators will be described in more detail below. .TP \f[B]++\f[R] \f[B]--\f[R] The prefix and postfix \f[B]increment\f[R] and \f[B]decrement\f[R] operators behave exactly like they would in C. They require a named expression (see the \f[I]Named Expressions\f[R] subsection) as an operand. .RS .PP The prefix versions of these operators are more efficient; use them where possible. .RE .TP \f[B]-\f[R] The \f[B]negation\f[R] operator returns \f[B]0\f[R] if a user attempts to negate any expression with the value \f[B]0\f[R]. Otherwise, a copy of the expression with its sign flipped is returned. .TP \f[B]!\f[R] The \f[B]boolean not\f[R] operator returns \f[B]1\f[R] if the expression is \f[B]0\f[R], or \f[B]0\f[R] otherwise. .RS .PP This is a \f[B]non-portable extension\f[R]. .RE .TP \f[B]$\f[R] The \f[B]truncation\f[R] operator returns a copy of the given expression with all of its \f[I]scale\f[R] removed. .RS .PP This is a \f[B]non-portable extension\f[R]. .RE .TP \f[B]\[at]\f[R] The \f[B]set precision\f[R] operator takes two expressions and returns a copy of the first with its \f[I]scale\f[R] equal to the value of the second expression. That could either mean that the number is returned without change (if the \f[I]scale\f[R] of the first expression matches the value of the second expression), extended (if it is less), or truncated (if it is more). .RS .PP The second expression must be an integer (no \f[I]scale\f[R]) and non-negative. .PP This is a \f[B]non-portable extension\f[R]. .RE .TP \f[B]\[ha]\f[R] The \f[B]power\f[R] operator (not the \f[B]exclusive or\f[R] operator, as it would be in C) takes two expressions and raises the first to the power of the value of the second. The \f[I]scale\f[R] of the result is equal to \f[B]scale\f[R]. .RS .PP The second expression must be an integer (no \f[I]scale\f[R]), and if it is negative, the first value must be non-zero. .RE .TP \f[B]*\f[R] The \f[B]multiply\f[R] operator takes two expressions, multiplies them, and returns the product. If \f[B]a\f[R] is the \f[I]scale\f[R] of the first expression and \f[B]b\f[R] is the \f[I]scale\f[R] of the second expression, the \f[I]scale\f[R] of the result is equal to \f[B]min(a+b,max(scale,a,b))\f[R] where \f[B]min()\f[R] and \f[B]max()\f[R] return the obvious values. .TP \f[B]/\f[R] The \f[B]divide\f[R] operator takes two expressions, divides them, and returns the quotient. The \f[I]scale\f[R] of the result shall be the value of \f[B]scale\f[R]. .RS .PP The second expression must be non-zero. .RE .TP \f[B]%\f[R] The \f[B]modulus\f[R] operator takes two expressions, \f[B]a\f[R] and \f[B]b\f[R], and evaluates them by 1) Computing \f[B]a/b\f[R] to current \f[B]scale\f[R] and 2) Using the result of step 1 to calculate \f[B]a-(a/b)*b\f[R] to \f[I]scale\f[R] \f[B]max(scale+scale(b),scale(a))\f[R]. .RS .PP The second expression must be non-zero. .RE .TP \f[B]+\f[R] The \f[B]add\f[R] operator takes two expressions, \f[B]a\f[R] and \f[B]b\f[R], and returns the sum, with a \f[I]scale\f[R] equal to the max of the \f[I]scale\f[R]s of \f[B]a\f[R] and \f[B]b\f[R]. .TP \f[B]-\f[R] The \f[B]subtract\f[R] operator takes two expressions, \f[B]a\f[R] and \f[B]b\f[R], and returns the difference, with a \f[I]scale\f[R] equal to the max of the \f[I]scale\f[R]s of \f[B]a\f[R] and \f[B]b\f[R]. .TP \f[B]<<\f[R] The \f[B]left shift\f[R] operator takes two expressions, \f[B]a\f[R] and \f[B]b\f[R], and returns a copy of the value of \f[B]a\f[R] with its decimal point moved \f[B]b\f[R] places to the right. .RS .PP The second expression must be an integer (no \f[I]scale\f[R]) and non-negative. .PP This is a \f[B]non-portable extension\f[R]. .RE .TP \f[B]>>\f[R] The \f[B]right shift\f[R] operator takes two expressions, \f[B]a\f[R] and \f[B]b\f[R], and returns a copy of the value of \f[B]a\f[R] with its decimal point moved \f[B]b\f[R] places to the left. .RS .PP The second expression must be an integer (no \f[I]scale\f[R]) and non-negative. .PP This is a \f[B]non-portable extension\f[R]. .RE .TP \f[B]=\f[R] \f[B]<<=\f[R] \f[B]>>=\f[R] \f[B]+=\f[R] \f[B]-=\f[R] \f[B]*=\f[R] \f[B]/=\f[R] \f[B]%=\f[R] \f[B]\[ha]=\f[R] \f[B]\[at]=\f[R] The \f[B]assignment\f[R] operators take two expressions, \f[B]a\f[R] and \f[B]b\f[R] where \f[B]a\f[R] is a named expression (see the \f[I]Named Expressions\f[R] subsection). .RS .PP For \f[B]=\f[R], \f[B]b\f[R] is copied and the result is assigned to \f[B]a\f[R]. For all others, \f[B]a\f[R] and \f[B]b\f[R] are applied as operands to the corresponding arithmetic operator and the result is assigned to \f[B]a\f[R]. .PP The \f[B]assignment\f[R] operators that correspond to operators that are extensions are themselves \f[B]non-portable extensions\f[R]. .RE .TP \f[B]==\f[R] \f[B]<=\f[R] \f[B]>=\f[R] \f[B]!=\f[R] \f[B]<\f[R] \f[B]>\f[R] The \f[B]relational\f[R] operators compare two expressions, \f[B]a\f[R] and \f[B]b\f[R], and if the relation holds, according to C language semantics, the result is \f[B]1\f[R]. Otherwise, it is \f[B]0\f[R]. .RS .PP Note that unlike in C, these operators have a lower precedence than the \f[B]assignment\f[R] operators, which means that \f[B]a=b>c\f[R] is interpreted as \f[B](a=b)>c\f[R]. .PP Also, unlike the standard (https://pubs.opengroup.org/onlinepubs/9699919799/utilities/bc.html) requires, these operators can appear anywhere any other expressions can be used. This allowance is a \f[B]non-portable extension\f[R]. .RE .TP \f[B]&&\f[R] The \f[B]boolean and\f[R] operator takes two expressions and returns \f[B]1\f[R] if both expressions are non-zero, \f[B]0\f[R] otherwise. .RS .PP This is \f[I]not\f[R] a short-circuit operator. .PP This is a \f[B]non-portable extension\f[R]. .RE .TP \f[B]||\f[R] The \f[B]boolean or\f[R] operator takes two expressions and returns \f[B]1\f[R] if one of the expressions is non-zero, \f[B]0\f[R] otherwise. .RS .PP This is \f[I]not\f[R] a short-circuit operator. .PP This is a \f[B]non-portable extension\f[R]. .RE .SS Statements .PP The following items are statements: .IP " 1." 4 \f[B]E\f[R] .IP " 2." 4 \f[B]{\f[R] \f[B]S\f[R] \f[B];\f[R] \&... \f[B];\f[R] \f[B]S\f[R] \f[B]}\f[R] .IP " 3." 4 \f[B]if\f[R] \f[B](\f[R] \f[B]E\f[R] \f[B])\f[R] \f[B]S\f[R] .IP " 4." 4 \f[B]if\f[R] \f[B](\f[R] \f[B]E\f[R] \f[B])\f[R] \f[B]S\f[R] \f[B]else\f[R] \f[B]S\f[R] .IP " 5." 4 \f[B]while\f[R] \f[B](\f[R] \f[B]E\f[R] \f[B])\f[R] \f[B]S\f[R] .IP " 6." 4 \f[B]for\f[R] \f[B](\f[R] \f[B]E\f[R] \f[B];\f[R] \f[B]E\f[R] \f[B];\f[R] \f[B]E\f[R] \f[B])\f[R] \f[B]S\f[R] .IP " 7." 4 An empty statement .IP " 8." 4 \f[B]break\f[R] .IP " 9." 4 \f[B]continue\f[R] .IP "10." 4 \f[B]quit\f[R] .IP "11." 4 \f[B]halt\f[R] .IP "12." 4 \f[B]limits\f[R] .IP "13." 4 A string of characters, enclosed in double quotes .IP "14." 4 \f[B]print\f[R] \f[B]E\f[R] \f[B],\f[R] \&... \f[B],\f[R] \f[B]E\f[R] .IP "15." 4 \f[B]stream\f[R] \f[B]E\f[R] \f[B],\f[R] \&... \f[B],\f[R] \f[B]E\f[R] .IP "16." 4 \f[B]I()\f[R], \f[B]I(E)\f[R], \f[B]I(E, E)\f[R], and so on, where \f[B]I\f[R] is an identifier for a \f[B]void\f[R] function (see the \f[I]Void Functions\f[R] subsection of the \f[B]FUNCTIONS\f[R] section). The \f[B]E\f[R] argument(s) may also be arrays of the form \f[B]I[]\f[R], which will automatically be turned into array references (see the \f[I]Array References\f[R] subsection of the \f[B]FUNCTIONS\f[R] section) if the corresponding parameter in the function definition is an array reference. .PP Numbers 4, 9, 11, 12, 14, 15, and 16 are \f[B]non-portable extensions\f[R]. .PP Also, as a \f[B]non-portable extension\f[R], any or all of the expressions in the header of a for loop may be omitted. If the condition (second expression) is omitted, it is assumed to be a constant \f[B]1\f[R]. .PP The \f[B]break\f[R] statement causes a loop to stop iterating and resume execution immediately following a loop. This is only allowed in loops. .PP The \f[B]continue\f[R] statement causes a loop iteration to stop early and returns to the start of the loop, including testing the loop condition. This is only allowed in loops. .PP The \f[B]if\f[R] \f[B]else\f[R] statement does the same thing as in C. .PP The \f[B]quit\f[R] statement causes bc(1) to quit, even if it is on a branch that will not be executed (it is a compile-time command). .PP The \f[B]halt\f[R] statement causes bc(1) to quit, if it is executed. (Unlike \f[B]quit\f[R] if it is on a branch of an \f[B]if\f[R] statement that is not executed, bc(1) does not quit.) .PP The \f[B]limits\f[R] statement prints the limits that this bc(1) is subject to. This is like the \f[B]quit\f[R] statement in that it is a compile-time command. .PP An expression by itself is evaluated and printed, followed by a newline. .PP Both scientific notation and engineering notation are available for printing the results of expressions. Scientific notation is activated by assigning \f[B]0\f[R] to \f[B]obase\f[R], and engineering notation is activated by assigning \f[B]1\f[R] to \f[B]obase\f[R]. To deactivate them, just assign a different value to \f[B]obase\f[R]. .PP Scientific notation and engineering notation are disabled if bc(1) is run with either the \f[B]-s\f[R] or \f[B]-w\f[R] command-line options (or equivalents). .PP Printing numbers in scientific notation and/or engineering notation is a \f[B]non-portable extension\f[R]. .SS Strings .PP If strings appear as a statement by themselves, they are printed without a trailing newline. .PP In addition to appearing as a lone statement by themselves, strings can be assigned to variables and array elements. They can also be passed to functions in variable parameters. .PP If any statement that expects a string is given a variable that had a string assigned to it, the statement acts as though it had received a string. .PP If any math operation is attempted on a string or a variable or array element that has been assigned a string, an error is raised, and bc(1) resets (see the \f[B]RESET\f[R] section). .PP Assigning strings to variables and array elements and passing them to functions are \f[B]non-portable extensions\f[R]. .SS Print Statement .PP The \[lq]expressions\[rq] in a \f[B]print\f[R] statement may also be strings. If they are, there are backslash escape sequences that are interpreted specially. What those sequences are, and what they cause to be printed, are shown below: .PP \f[B]\[rs]a\f[R]: \f[B]\[rs]a\f[R] .PP \f[B]\[rs]b\f[R]: \f[B]\[rs]b\f[R] .PP \f[B]\[rs]\[rs]\f[R]: \f[B]\[rs]\f[R] .PP \f[B]\[rs]e\f[R]: \f[B]\[rs]\f[R] .PP \f[B]\[rs]f\f[R]: \f[B]\[rs]f\f[R] .PP \f[B]\[rs]n\f[R]: \f[B]\[rs]n\f[R] .PP \f[B]\[rs]q\f[R]: \f[B]\[lq]\f[R] .PP \f[B]\[rs]r\f[R]: \f[B]\[rs]r\f[R] .PP \f[B]\[rs]t\f[R]: \f[B]\[rs]t\f[R] .PP Any other character following a backslash causes the backslash and character to be printed as-is. .PP Any non-string expression in a print statement shall be assigned to \f[B]last\f[R], like any other expression that is printed. .SS Stream Statement .PP The \[lq]expressions in a \f[B]stream\f[R] statement may also be strings. .PP If a \f[B]stream\f[R] statement is given a string, it prints the string as though the string had appeared as its own statement. In other words, the \f[B]stream\f[R] statement prints strings normally, without a newline. .PP If a \f[B]stream\f[R] statement is given a number, a copy of it is truncated and its absolute value is calculated. The result is then printed as though \f[B]obase\f[R] is \f[B]256\f[R] and each digit is interpreted as an 8-bit ASCII character, making it a byte stream. .SS Order of Evaluation .PP All expressions in a statment are evaluated left to right, except as necessary to maintain order of operations. This means, for example, assuming that \f[B]i\f[R] is equal to \f[B]0\f[R], in the expression .IP .nf \f[C] a[i++] = i++ \f[R] .fi .PP the first (or 0th) element of \f[B]a\f[R] is set to \f[B]1\f[R], and \f[B]i\f[R] is equal to \f[B]2\f[R] at the end of the expression. .PP This includes function arguments. Thus, assuming \f[B]i\f[R] is equal to \f[B]0\f[R], this means that in the expression .IP .nf \f[C] x(i++, i++) \f[R] .fi .PP the first argument passed to \f[B]x()\f[R] is \f[B]0\f[R], and the second argument is \f[B]1\f[R], while \f[B]i\f[R] is equal to \f[B]2\f[R] before the function starts executing. .SH FUNCTIONS .PP Function definitions are as follows: .IP .nf \f[C] define I(I,...,I){ auto I,...,I S;...;S return(E) } \f[R] .fi .PP Any \f[B]I\f[R] in the parameter list or \f[B]auto\f[R] list may be replaced with \f[B]I[]\f[R] to make a parameter or \f[B]auto\f[R] var an array, and any \f[B]I\f[R] in the parameter list may be replaced with \f[B]*I[]\f[R] to make a parameter an array reference. Callers of functions that take array references should not put an asterisk in the call; they must be called with just \f[B]I[]\f[R] like normal array parameters and will be automatically converted into references. .PP As a \f[B]non-portable extension\f[R], the opening brace of a \f[B]define\f[R] statement may appear on the next line. .PP As a \f[B]non-portable extension\f[R], the return statement may also be in one of the following forms: .IP "1." 3 \f[B]return\f[R] .IP "2." 3 \f[B]return\f[R] \f[B](\f[R] \f[B])\f[R] .IP "3." 3 \f[B]return\f[R] \f[B]E\f[R] .PP The first two, or not specifying a \f[B]return\f[R] statement, is equivalent to \f[B]return (0)\f[R], unless the function is a \f[B]void\f[R] function (see the \f[I]Void Functions\f[R] subsection below). .SS Void Functions .PP Functions can also be \f[B]void\f[R] functions, defined as follows: .IP .nf \f[C] define void I(I,...,I){ auto I,...,I S;...;S return } \f[R] .fi .PP They can only be used as standalone expressions, where such an expression would be printed alone, except in a print statement. .PP Void functions can only use the first two \f[B]return\f[R] statements listed above. They can also omit the return statement entirely. .PP The word \[lq]void\[rq] is not treated as a keyword; it is still possible to have variables, arrays, and functions named \f[B]void\f[R]. The word \[lq]void\[rq] is only treated specially right after the \f[B]define\f[R] keyword. .PP This is a \f[B]non-portable extension\f[R]. .SS Array References .PP For any array in the parameter list, if the array is declared in the form .IP .nf \f[C] *I[] \f[R] .fi .PP it is a \f[B]reference\f[R]. Any changes to the array in the function are reflected, when the function returns, to the array that was passed in. .PP Other than this, all function arguments are passed by value. .PP This is a \f[B]non-portable extension\f[R]. .SH LIBRARY .PP All of the functions below, including the functions in the extended math library (see the \f[I]Extended Library\f[R] subsection below), are available when the \f[B]-l\f[R] or \f[B]--mathlib\f[R] command-line flags are given, except that the extended math library is not available when the \f[B]-s\f[R] option, the \f[B]-w\f[R] option, or equivalents are given. .SS Standard Library .PP The standard (https://pubs.opengroup.org/onlinepubs/9699919799/utilities/bc.html) defines the following functions for the math library: .TP \f[B]s(x)\f[R] Returns the sine of \f[B]x\f[R], which is assumed to be in radians. .RS .PP This is a transcendental function (see the \f[I]Transcendental Functions\f[R] subsection below). .RE .TP \f[B]c(x)\f[R] Returns the cosine of \f[B]x\f[R], which is assumed to be in radians. .RS .PP This is a transcendental function (see the \f[I]Transcendental Functions\f[R] subsection below). .RE .TP \f[B]a(x)\f[R] Returns the arctangent of \f[B]x\f[R], in radians. .RS .PP This is a transcendental function (see the \f[I]Transcendental Functions\f[R] subsection below). .RE .TP \f[B]l(x)\f[R] Returns the natural logarithm of \f[B]x\f[R]. .RS .PP This is a transcendental function (see the \f[I]Transcendental Functions\f[R] subsection below). .RE .TP \f[B]e(x)\f[R] Returns the mathematical constant \f[B]e\f[R] raised to the power of \f[B]x\f[R]. .RS .PP This is a transcendental function (see the \f[I]Transcendental Functions\f[R] subsection below). .RE .TP \f[B]j(x, n)\f[R] Returns the bessel integer order \f[B]n\f[R] (truncated) of \f[B]x\f[R]. .RS .PP This is a transcendental function (see the \f[I]Transcendental Functions\f[R] subsection below). .RE .SS Extended Library .PP The extended library is \f[I]not\f[R] loaded when the \f[B]-s\f[R]/\f[B]--standard\f[R] or \f[B]-w\f[R]/\f[B]--warn\f[R] options are given since they are not part of the library defined by the standard (https://pubs.opengroup.org/onlinepubs/9699919799/utilities/bc.html). .PP The extended library is a \f[B]non-portable extension\f[R]. .TP \f[B]p(x, y)\f[R] Calculates \f[B]x\f[R] to the power of \f[B]y\f[R], even if \f[B]y\f[R] is not an integer, and returns the result to the current \f[B]scale\f[R]. .RS .PP It is an error if \f[B]y\f[R] is negative and \f[B]x\f[R] is \f[B]0\f[R]. .PP This is a transcendental function (see the \f[I]Transcendental Functions\f[R] subsection below). .RE .TP \f[B]r(x, p)\f[R] Returns \f[B]x\f[R] rounded to \f[B]p\f[R] decimal places according to the rounding mode round half away from \f[B]0\f[R] (https://en.wikipedia.org/wiki/Rounding#Round_half_away_from_zero). .TP \f[B]ceil(x, p)\f[R] Returns \f[B]x\f[R] rounded to \f[B]p\f[R] decimal places according to the rounding mode round away from \f[B]0\f[R] (https://en.wikipedia.org/wiki/Rounding#Rounding_away_from_zero). .TP \f[B]f(x)\f[R] Returns the factorial of the truncated absolute value of \f[B]x\f[R]. .TP \f[B]perm(n, k)\f[R] Returns the permutation of the truncated absolute value of \f[B]n\f[R] of the truncated absolute value of \f[B]k\f[R], if \f[B]k <= n\f[R]. If not, it returns \f[B]0\f[R]. .TP \f[B]comb(n, k)\f[R] Returns the combination of the truncated absolute value of \f[B]n\f[R] of the truncated absolute value of \f[B]k\f[R], if \f[B]k <= n\f[R]. If not, it returns \f[B]0\f[R]. .TP \f[B]l2(x)\f[R] Returns the logarithm base \f[B]2\f[R] of \f[B]x\f[R]. .RS .PP This is a transcendental function (see the \f[I]Transcendental Functions\f[R] subsection below). .RE .TP \f[B]l10(x)\f[R] Returns the logarithm base \f[B]10\f[R] of \f[B]x\f[R]. .RS .PP This is a transcendental function (see the \f[I]Transcendental Functions\f[R] subsection below). .RE .TP \f[B]log(x, b)\f[R] Returns the logarithm base \f[B]b\f[R] of \f[B]x\f[R]. .RS .PP This is a transcendental function (see the \f[I]Transcendental Functions\f[R] subsection below). .RE .TP \f[B]cbrt(x)\f[R] Returns the cube root of \f[B]x\f[R]. .TP \f[B]root(x, n)\f[R] Calculates the truncated value of \f[B]n\f[R], \f[B]r\f[R], and returns the \f[B]r\f[R]th root of \f[B]x\f[R] to the current \f[B]scale\f[R]. .RS .PP If \f[B]r\f[R] is \f[B]0\f[R] or negative, this raises an error and causes bc(1) to reset (see the \f[B]RESET\f[R] section). It also raises an error and causes bc(1) to reset if \f[B]r\f[R] is even and \f[B]x\f[R] is negative. .RE .TP \f[B]gcd(a, b)\f[R] Returns the greatest common divisor (factor) of the truncated absolute value of \f[B]a\f[R] and the truncated absolute value of \f[B]b\f[R]. .TP \f[B]lcm(a, b)\f[R] Returns the least common multiple of the truncated absolute value of \f[B]a\f[R] and the truncated absolute value of \f[B]b\f[R]. .TP \f[B]pi(p)\f[R] Returns \f[B]pi\f[R] to \f[B]p\f[R] decimal places. .RS .PP This is a transcendental function (see the \f[I]Transcendental Functions\f[R] subsection below). .RE .TP \f[B]t(x)\f[R] Returns the tangent of \f[B]x\f[R], which is assumed to be in radians. .RS .PP This is a transcendental function (see the \f[I]Transcendental Functions\f[R] subsection below). .RE .TP \f[B]a2(y, x)\f[R] Returns the arctangent of \f[B]y/x\f[R], in radians. If both \f[B]y\f[R] and \f[B]x\f[R] are equal to \f[B]0\f[R], it raises an error and causes bc(1) to reset (see the \f[B]RESET\f[R] section). Otherwise, if \f[B]x\f[R] is greater than \f[B]0\f[R], it returns \f[B]a(y/x)\f[R]. If \f[B]x\f[R] is less than \f[B]0\f[R], and \f[B]y\f[R] is greater than or equal to \f[B]0\f[R], it returns \f[B]a(y/x)+pi\f[R]. If \f[B]x\f[R] is less than \f[B]0\f[R], and \f[B]y\f[R] is less than \f[B]0\f[R], it returns \f[B]a(y/x)-pi\f[R]. If \f[B]x\f[R] is equal to \f[B]0\f[R], and \f[B]y\f[R] is greater than \f[B]0\f[R], it returns \f[B]pi/2\f[R]. If \f[B]x\f[R] is equal to \f[B]0\f[R], and \f[B]y\f[R] is less than \f[B]0\f[R], it returns \f[B]-pi/2\f[R]. .RS .PP This function is the same as the \f[B]atan2()\f[R] function in many programming languages. .PP This is a transcendental function (see the \f[I]Transcendental Functions\f[R] subsection below). .RE .TP \f[B]sin(x)\f[R] Returns the sine of \f[B]x\f[R], which is assumed to be in radians. .RS .PP This is an alias of \f[B]s(x)\f[R]. .PP This is a transcendental function (see the \f[I]Transcendental Functions\f[R] subsection below). .RE .TP \f[B]cos(x)\f[R] Returns the cosine of \f[B]x\f[R], which is assumed to be in radians. .RS .PP This is an alias of \f[B]c(x)\f[R]. .PP This is a transcendental function (see the \f[I]Transcendental Functions\f[R] subsection below). .RE .TP \f[B]tan(x)\f[R] Returns the tangent of \f[B]x\f[R], which is assumed to be in radians. .RS .PP If \f[B]x\f[R] is equal to \f[B]1\f[R] or \f[B]-1\f[R], this raises an error and causes bc(1) to reset (see the \f[B]RESET\f[R] section). .PP This is an alias of \f[B]t(x)\f[R]. .PP This is a transcendental function (see the \f[I]Transcendental Functions\f[R] subsection below). .RE .TP \f[B]atan(x)\f[R] Returns the arctangent of \f[B]x\f[R], in radians. .RS .PP This is an alias of \f[B]a(x)\f[R]. .PP This is a transcendental function (see the \f[I]Transcendental Functions\f[R] subsection below). .RE .TP \f[B]atan2(y, x)\f[R] Returns the arctangent of \f[B]y/x\f[R], in radians. If both \f[B]y\f[R] and \f[B]x\f[R] are equal to \f[B]0\f[R], it raises an error and causes bc(1) to reset (see the \f[B]RESET\f[R] section). Otherwise, if \f[B]x\f[R] is greater than \f[B]0\f[R], it returns \f[B]a(y/x)\f[R]. If \f[B]x\f[R] is less than \f[B]0\f[R], and \f[B]y\f[R] is greater than or equal to \f[B]0\f[R], it returns \f[B]a(y/x)+pi\f[R]. If \f[B]x\f[R] is less than \f[B]0\f[R], and \f[B]y\f[R] is less than \f[B]0\f[R], it returns \f[B]a(y/x)-pi\f[R]. If \f[B]x\f[R] is equal to \f[B]0\f[R], and \f[B]y\f[R] is greater than \f[B]0\f[R], it returns \f[B]pi/2\f[R]. If \f[B]x\f[R] is equal to \f[B]0\f[R], and \f[B]y\f[R] is less than \f[B]0\f[R], it returns \f[B]-pi/2\f[R]. .RS .PP This function is the same as the \f[B]atan2()\f[R] function in many programming languages. .PP This is an alias of \f[B]a2(y, x)\f[R]. .PP This is a transcendental function (see the \f[I]Transcendental Functions\f[R] subsection below). .RE .TP \f[B]r2d(x)\f[R] Converts \f[B]x\f[R] from radians to degrees and returns the result. .RS .PP This is a transcendental function (see the \f[I]Transcendental Functions\f[R] subsection below). .RE .TP \f[B]d2r(x)\f[R] Converts \f[B]x\f[R] from degrees to radians and returns the result. .RS .PP This is a transcendental function (see the \f[I]Transcendental Functions\f[R] subsection below). .RE .TP \f[B]frand(p)\f[R] Generates a pseudo-random number between \f[B]0\f[R] (inclusive) and \f[B]1\f[R] (exclusive) with the number of decimal digits after the decimal point equal to the truncated absolute value of \f[B]p\f[R]. If \f[B]p\f[R] is not \f[B]0\f[R], then calling this function will change the value of \f[B]seed\f[R]. If \f[B]p\f[R] is \f[B]0\f[R], then \f[B]0\f[R] is returned, and \f[B]seed\f[R] is \f[I]not\f[R] changed. .TP \f[B]ifrand(i, p)\f[R] Generates a pseudo-random number that is between \f[B]0\f[R] (inclusive) and the truncated absolute value of \f[B]i\f[R] (exclusive) with the number of decimal digits after the decimal point equal to the truncated absolute value of \f[B]p\f[R]. If the absolute value of \f[B]i\f[R] is greater than or equal to \f[B]2\f[R], and \f[B]p\f[R] is not \f[B]0\f[R], then calling this function will change the value of \f[B]seed\f[R]; otherwise, \f[B]0\f[R] is returned and \f[B]seed\f[R] is not changed. .TP \f[B]srand(x)\f[R] Returns \f[B]x\f[R] with its sign flipped with probability \f[B]0.5\f[R]. In other words, it randomizes the sign of \f[B]x\f[R]. .TP \f[B]brand()\f[R] Returns a random boolean value (either \f[B]0\f[R] or \f[B]1\f[R]). .TP \f[B]band(a, b)\f[R] Takes the truncated absolute value of both \f[B]a\f[R] and \f[B]b\f[R] and calculates and returns the result of the bitwise \f[B]and\f[R] operation between them. .RS .PP If you want to use signed two\[cq]s complement arguments, use \f[B]s2u(x)\f[R] to convert. .RE .TP \f[B]bor(a, b)\f[R] Takes the truncated absolute value of both \f[B]a\f[R] and \f[B]b\f[R] and calculates and returns the result of the bitwise \f[B]or\f[R] operation between them. .RS .PP If you want to use signed two\[cq]s complement arguments, use \f[B]s2u(x)\f[R] to convert. .RE .TP \f[B]bxor(a, b)\f[R] Takes the truncated absolute value of both \f[B]a\f[R] and \f[B]b\f[R] and calculates and returns the result of the bitwise \f[B]xor\f[R] operation between them. .RS .PP If you want to use signed two\[cq]s complement arguments, use \f[B]s2u(x)\f[R] to convert. .RE .TP \f[B]bshl(a, b)\f[R] Takes the truncated absolute value of both \f[B]a\f[R] and \f[B]b\f[R] and calculates and returns the result of \f[B]a\f[R] bit-shifted left by \f[B]b\f[R] places. .RS .PP If you want to use signed two\[cq]s complement arguments, use \f[B]s2u(x)\f[R] to convert. .RE .TP \f[B]bshr(a, b)\f[R] Takes the truncated absolute value of both \f[B]a\f[R] and \f[B]b\f[R] and calculates and returns the truncated result of \f[B]a\f[R] bit-shifted right by \f[B]b\f[R] places. .RS .PP If you want to use signed two\[cq]s complement arguments, use \f[B]s2u(x)\f[R] to convert. .RE .TP \f[B]bnotn(x, n)\f[R] Takes the truncated absolute value of \f[B]x\f[R] and does a bitwise not as though it has the same number of bytes as the truncated absolute value of \f[B]n\f[R]. .RS .PP If you want to a use signed two\[cq]s complement argument, use \f[B]s2u(x)\f[R] to convert. .RE .TP \f[B]bnot8(x)\f[R] Does a bitwise not of the truncated absolute value of \f[B]x\f[R] as though it has \f[B]8\f[R] binary digits (1 unsigned byte). .RS .PP If you want to a use signed two\[cq]s complement argument, use \f[B]s2u(x)\f[R] to convert. .RE .TP \f[B]bnot16(x)\f[R] Does a bitwise not of the truncated absolute value of \f[B]x\f[R] as though it has \f[B]16\f[R] binary digits (2 unsigned bytes). .RS .PP If you want to a use signed two\[cq]s complement argument, use \f[B]s2u(x)\f[R] to convert. .RE .TP \f[B]bnot32(x)\f[R] Does a bitwise not of the truncated absolute value of \f[B]x\f[R] as though it has \f[B]32\f[R] binary digits (4 unsigned bytes). .RS .PP If you want to a use signed two\[cq]s complement argument, use \f[B]s2u(x)\f[R] to convert. .RE .TP \f[B]bnot64(x)\f[R] Does a bitwise not of the truncated absolute value of \f[B]x\f[R] as though it has \f[B]64\f[R] binary digits (8 unsigned bytes). .RS .PP If you want to a use signed two\[cq]s complement argument, use \f[B]s2u(x)\f[R] to convert. .RE .TP \f[B]bnot(x)\f[R] Does a bitwise not of the truncated absolute value of \f[B]x\f[R] as though it has the minimum number of power of two unsigned bytes. .RS .PP If you want to a use signed two\[cq]s complement argument, use \f[B]s2u(x)\f[R] to convert. .RE .TP \f[B]brevn(x, n)\f[R] Runs a bit reversal on the truncated absolute value of \f[B]x\f[R] as though it has the same number of 8-bit bytes as the truncated absolute value of \f[B]n\f[R]. .RS .PP If you want to a use signed two\[cq]s complement argument, use \f[B]s2u(x)\f[R] to convert. .RE .TP \f[B]brev8(x)\f[R] Runs a bit reversal on the truncated absolute value of \f[B]x\f[R] as though it has 8 binary digits (1 unsigned byte). .RS .PP If you want to a use signed two\[cq]s complement argument, use \f[B]s2u(x)\f[R] to convert. .RE .TP \f[B]brev16(x)\f[R] Runs a bit reversal on the truncated absolute value of \f[B]x\f[R] as though it has 16 binary digits (2 unsigned bytes). .RS .PP If you want to a use signed two\[cq]s complement argument, use \f[B]s2u(x)\f[R] to convert. .RE .TP \f[B]brev32(x)\f[R] Runs a bit reversal on the truncated absolute value of \f[B]x\f[R] as though it has 32 binary digits (4 unsigned bytes). .RS .PP If you want to a use signed two\[cq]s complement argument, use \f[B]s2u(x)\f[R] to convert. .RE .TP \f[B]brev64(x)\f[R] Runs a bit reversal on the truncated absolute value of \f[B]x\f[R] as though it has 64 binary digits (8 unsigned bytes). .RS .PP If you want to a use signed two\[cq]s complement argument, use \f[B]s2u(x)\f[R] to convert. .RE .TP \f[B]brev(x)\f[R] Runs a bit reversal on the truncated absolute value of \f[B]x\f[R] as though it has the minimum number of power of two unsigned bytes. .RS .PP If you want to a use signed two\[cq]s complement argument, use \f[B]s2u(x)\f[R] to convert. .RE .TP \f[B]broln(x, p, n)\f[R] Does a left bitwise rotatation of the truncated absolute value of \f[B]x\f[R], as though it has the same number of unsigned 8-bit bytes as the truncated absolute value of \f[B]n\f[R], by the number of places equal to the truncated absolute value of \f[B]p\f[R] modded by the \f[B]2\f[R] to the power of the number of binary digits in \f[B]n\f[R] 8-bit bytes. .RS .PP If you want to a use signed two\[cq]s complement argument, use \f[B]s2u(x)\f[R] to convert. .RE .TP \f[B]brol8(x, p)\f[R] Does a left bitwise rotatation of the truncated absolute value of \f[B]x\f[R], as though it has \f[B]8\f[R] binary digits (\f[B]1\f[R] unsigned byte), by the number of places equal to the truncated absolute value of \f[B]p\f[R] modded by \f[B]2\f[R] to the power of \f[B]8\f[R]. .RS .PP If you want to a use signed two\[cq]s complement argument, use \f[B]s2u(x)\f[R] to convert. .RE .TP \f[B]brol16(x, p)\f[R] Does a left bitwise rotatation of the truncated absolute value of \f[B]x\f[R], as though it has \f[B]16\f[R] binary digits (\f[B]2\f[R] unsigned bytes), by the number of places equal to the truncated absolute value of \f[B]p\f[R] modded by \f[B]2\f[R] to the power of \f[B]16\f[R]. .RS .PP If you want to a use signed two\[cq]s complement argument, use \f[B]s2u(x)\f[R] to convert. .RE .TP \f[B]brol32(x, p)\f[R] Does a left bitwise rotatation of the truncated absolute value of \f[B]x\f[R], as though it has \f[B]32\f[R] binary digits (\f[B]2\f[R] unsigned bytes), by the number of places equal to the truncated absolute value of \f[B]p\f[R] modded by \f[B]2\f[R] to the power of \f[B]32\f[R]. .RS .PP If you want to a use signed two\[cq]s complement argument, use \f[B]s2u(x)\f[R] to convert. .RE .TP \f[B]brol64(x, p)\f[R] Does a left bitwise rotatation of the truncated absolute value of \f[B]x\f[R], as though it has \f[B]64\f[R] binary digits (\f[B]2\f[R] unsigned bytes), by the number of places equal to the truncated absolute value of \f[B]p\f[R] modded by \f[B]2\f[R] to the power of \f[B]64\f[R]. .RS .PP If you want to a use signed two\[cq]s complement argument, use \f[B]s2u(x)\f[R] to convert. .RE .TP \f[B]brol(x, p)\f[R] Does a left bitwise rotatation of the truncated absolute value of \f[B]x\f[R], as though it has the minimum number of power of two unsigned 8-bit bytes, by the number of places equal to the truncated absolute value of \f[B]p\f[R] modded by 2 to the power of the number of binary digits in the minimum number of 8-bit bytes. .RS .PP If you want to a use signed two\[cq]s complement argument, use \f[B]s2u(x)\f[R] to convert. .RE .TP \f[B]brorn(x, p, n)\f[R] Does a right bitwise rotatation of the truncated absolute value of \f[B]x\f[R], as though it has the same number of unsigned 8-bit bytes as the truncated absolute value of \f[B]n\f[R], by the number of places equal to the truncated absolute value of \f[B]p\f[R] modded by the \f[B]2\f[R] to the power of the number of binary digits in \f[B]n\f[R] 8-bit bytes. .RS .PP If you want to a use signed two\[cq]s complement argument, use \f[B]s2u(x)\f[R] to convert. .RE .TP \f[B]bror8(x, p)\f[R] Does a right bitwise rotatation of the truncated absolute value of \f[B]x\f[R], as though it has \f[B]8\f[R] binary digits (\f[B]1\f[R] unsigned byte), by the number of places equal to the truncated absolute value of \f[B]p\f[R] modded by \f[B]2\f[R] to the power of \f[B]8\f[R]. .RS .PP If you want to a use signed two\[cq]s complement argument, use \f[B]s2u(x)\f[R] to convert. .RE .TP \f[B]bror16(x, p)\f[R] Does a right bitwise rotatation of the truncated absolute value of \f[B]x\f[R], as though it has \f[B]16\f[R] binary digits (\f[B]2\f[R] unsigned bytes), by the number of places equal to the truncated absolute value of \f[B]p\f[R] modded by \f[B]2\f[R] to the power of \f[B]16\f[R]. .RS .PP If you want to a use signed two\[cq]s complement argument, use \f[B]s2u(x)\f[R] to convert. .RE .TP \f[B]bror32(x, p)\f[R] Does a right bitwise rotatation of the truncated absolute value of \f[B]x\f[R], as though it has \f[B]32\f[R] binary digits (\f[B]2\f[R] unsigned bytes), by the number of places equal to the truncated absolute value of \f[B]p\f[R] modded by \f[B]2\f[R] to the power of \f[B]32\f[R]. .RS .PP If you want to a use signed two\[cq]s complement argument, use \f[B]s2u(x)\f[R] to convert. .RE .TP \f[B]bror64(x, p)\f[R] Does a right bitwise rotatation of the truncated absolute value of \f[B]x\f[R], as though it has \f[B]64\f[R] binary digits (\f[B]2\f[R] unsigned bytes), by the number of places equal to the truncated absolute value of \f[B]p\f[R] modded by \f[B]2\f[R] to the power of \f[B]64\f[R]. .RS .PP If you want to a use signed two\[cq]s complement argument, use \f[B]s2u(x)\f[R] to convert. .RE .TP \f[B]bror(x, p)\f[R] Does a right bitwise rotatation of the truncated absolute value of \f[B]x\f[R], as though it has the minimum number of power of two unsigned 8-bit bytes, by the number of places equal to the truncated absolute value of \f[B]p\f[R] modded by 2 to the power of the number of binary digits in the minimum number of 8-bit bytes. .RS .PP If you want to a use signed two\[cq]s complement argument, use \f[B]s2u(x)\f[R] to convert. .RE .TP \f[B]bmodn(x, n)\f[R] Returns the modulus of the truncated absolute value of \f[B]x\f[R] by \f[B]2\f[R] to the power of the multiplication of the truncated absolute value of \f[B]n\f[R] and \f[B]8\f[R]. .RS .PP If you want to a use signed two\[cq]s complement argument, use \f[B]s2u(x)\f[R] to convert. .RE .TP \f[B]bmod8(x, n)\f[R] Returns the modulus of the truncated absolute value of \f[B]x\f[R] by \f[B]2\f[R] to the power of \f[B]8\f[R]. .RS .PP If you want to a use signed two\[cq]s complement argument, use \f[B]s2u(x)\f[R] to convert. .RE .TP \f[B]bmod16(x, n)\f[R] Returns the modulus of the truncated absolute value of \f[B]x\f[R] by \f[B]2\f[R] to the power of \f[B]16\f[R]. .RS .PP If you want to a use signed two\[cq]s complement argument, use \f[B]s2u(x)\f[R] to convert. .RE .TP \f[B]bmod32(x, n)\f[R] Returns the modulus of the truncated absolute value of \f[B]x\f[R] by \f[B]2\f[R] to the power of \f[B]32\f[R]. .RS .PP If you want to a use signed two\[cq]s complement argument, use \f[B]s2u(x)\f[R] to convert. .RE .TP \f[B]bmod64(x, n)\f[R] Returns the modulus of the truncated absolute value of \f[B]x\f[R] by \f[B]2\f[R] to the power of \f[B]64\f[R]. .RS .PP If you want to a use signed two\[cq]s complement argument, use \f[B]s2u(x)\f[R] to convert. .RE .TP \f[B]bunrev(t)\f[R] Assumes \f[B]t\f[R] is a bitwise-reversed number with an extra set bit one place more significant than the real most significant bit (which was the least significant bit in the original number). This number is reversed and returned without the extra set bit. .RS .PP This function is used to implement other bitwise functions; it is not meant to be used by users, but it can be. .RE .TP \f[B]plz(x)\f[R] If \f[B]x\f[R] is not equal to \f[B]0\f[R] and greater that \f[B]-1\f[R] and less than \f[B]1\f[R], it is printed with a leading zero, regardless of the use of the \f[B]-z\f[R] option (see the \f[B]OPTIONS\f[R] section) and without a trailing newline. .RS .PP Otherwise, \f[B]x\f[R] is printed normally, without a trailing newline. .RE .TP \f[B]plznl(x)\f[R] If \f[B]x\f[R] is not equal to \f[B]0\f[R] and greater that \f[B]-1\f[R] and less than \f[B]1\f[R], it is printed with a leading zero, regardless of the use of the \f[B]-z\f[R] option (see the \f[B]OPTIONS\f[R] section) and with a trailing newline. .RS .PP Otherwise, \f[B]x\f[R] is printed normally, with a trailing newline. .RE .TP \f[B]pnlz(x)\f[R] If \f[B]x\f[R] is not equal to \f[B]0\f[R] and greater that \f[B]-1\f[R] and less than \f[B]1\f[R], it is printed without a leading zero, regardless of the use of the \f[B]-z\f[R] option (see the \f[B]OPTIONS\f[R] section) and without a trailing newline. .RS .PP Otherwise, \f[B]x\f[R] is printed normally, without a trailing newline. .RE .TP \f[B]pnlznl(x)\f[R] If \f[B]x\f[R] is not equal to \f[B]0\f[R] and greater that \f[B]-1\f[R] and less than \f[B]1\f[R], it is printed without a leading zero, regardless of the use of the \f[B]-z\f[R] option (see the \f[B]OPTIONS\f[R] section) and with a trailing newline. .RS .PP Otherwise, \f[B]x\f[R] is printed normally, with a trailing newline. .RE .TP \f[B]ubytes(x)\f[R] Returns the numbers of unsigned integer bytes required to hold the truncated absolute value of \f[B]x\f[R]. .TP \f[B]sbytes(x)\f[R] Returns the numbers of signed, two\[cq]s-complement integer bytes required to hold the truncated value of \f[B]x\f[R]. .TP \f[B]s2u(x)\f[R] Returns \f[B]x\f[R] if it is non-negative. If it \f[I]is\f[R] negative, then it calculates what \f[B]x\f[R] would be as a 2\[cq]s-complement signed integer and returns the non-negative integer that would have the same representation in binary. .TP \f[B]s2un(x,n)\f[R] Returns \f[B]x\f[R] if it is non-negative. If it \f[I]is\f[R] negative, then it calculates what \f[B]x\f[R] would be as a 2\[cq]s-complement signed integer with \f[B]n\f[R] bytes and returns the non-negative integer that would have the same representation in binary. If \f[B]x\f[R] cannot fit into \f[B]n\f[R] 2\[cq]s-complement signed bytes, it is truncated to fit. .TP \f[B]hex(x)\f[R] Outputs the hexadecimal (base \f[B]16\f[R]) representation of \f[B]x\f[R]. .RS .PP This is a \f[B]void\f[R] function (see the \f[I]Void Functions\f[R] subsection of the \f[B]FUNCTIONS\f[R] section). .RE .TP \f[B]binary(x)\f[R] Outputs the binary (base \f[B]2\f[R]) representation of \f[B]x\f[R]. .RS .PP This is a \f[B]void\f[R] function (see the \f[I]Void Functions\f[R] subsection of the \f[B]FUNCTIONS\f[R] section). .RE .TP \f[B]output(x, b)\f[R] Outputs the base \f[B]b\f[R] representation of \f[B]x\f[R]. .RS .PP This is a \f[B]void\f[R] function (see the \f[I]Void Functions\f[R] subsection of the \f[B]FUNCTIONS\f[R] section). .RE .TP \f[B]uint(x)\f[R] Outputs the representation, in binary and hexadecimal, of \f[B]x\f[R] as an unsigned integer in as few power of two bytes as possible. Both outputs are split into bytes separated by spaces. .RS .PP If \f[B]x\f[R] is not an integer or is negative, an error message is printed instead, but bc(1) is not reset (see the \f[B]RESET\f[R] section). .PP This is a \f[B]void\f[R] function (see the \f[I]Void Functions\f[R] subsection of the \f[B]FUNCTIONS\f[R] section). .RE .TP \f[B]int(x)\f[R] Outputs the representation, in binary and hexadecimal, of \f[B]x\f[R] as a signed, two\[cq]s-complement integer in as few power of two bytes as possible. Both outputs are split into bytes separated by spaces. .RS .PP If \f[B]x\f[R] is not an integer, an error message is printed instead, but bc(1) is not reset (see the \f[B]RESET\f[R] section). .PP This is a \f[B]void\f[R] function (see the \f[I]Void Functions\f[R] subsection of the \f[B]FUNCTIONS\f[R] section). .RE .TP \f[B]uintn(x, n)\f[R] Outputs the representation, in binary and hexadecimal, of \f[B]x\f[R] as an unsigned integer in \f[B]n\f[R] bytes. Both outputs are split into bytes separated by spaces. .RS .PP If \f[B]x\f[R] is not an integer, is negative, or cannot fit into \f[B]n\f[R] bytes, an error message is printed instead, but bc(1) is not reset (see the \f[B]RESET\f[R] section). .PP This is a \f[B]void\f[R] function (see the \f[I]Void Functions\f[R] subsection of the \f[B]FUNCTIONS\f[R] section). .RE .TP \f[B]intn(x, n)\f[R] Outputs the representation, in binary and hexadecimal, of \f[B]x\f[R] as a signed, two\[cq]s-complement integer in \f[B]n\f[R] bytes. Both outputs are split into bytes separated by spaces. .RS .PP If \f[B]x\f[R] is not an integer or cannot fit into \f[B]n\f[R] bytes, an error message is printed instead, but bc(1) is not reset (see the \f[B]RESET\f[R] section). .PP This is a \f[B]void\f[R] function (see the \f[I]Void Functions\f[R] subsection of the \f[B]FUNCTIONS\f[R] section). .RE .TP \f[B]uint8(x)\f[R] Outputs the representation, in binary and hexadecimal, of \f[B]x\f[R] as an unsigned integer in \f[B]1\f[R] byte. Both outputs are split into bytes separated by spaces. .RS .PP If \f[B]x\f[R] is not an integer, is negative, or cannot fit into \f[B]1\f[R] byte, an error message is printed instead, but bc(1) is not reset (see the \f[B]RESET\f[R] section). .PP This is a \f[B]void\f[R] function (see the \f[I]Void Functions\f[R] subsection of the \f[B]FUNCTIONS\f[R] section). .RE .TP \f[B]int8(x)\f[R] Outputs the representation, in binary and hexadecimal, of \f[B]x\f[R] as a signed, two\[cq]s-complement integer in \f[B]1\f[R] byte. Both outputs are split into bytes separated by spaces. .RS .PP If \f[B]x\f[R] is not an integer or cannot fit into \f[B]1\f[R] byte, an error message is printed instead, but bc(1) is not reset (see the \f[B]RESET\f[R] section). .PP This is a \f[B]void\f[R] function (see the \f[I]Void Functions\f[R] subsection of the \f[B]FUNCTIONS\f[R] section). .RE .TP \f[B]uint16(x)\f[R] Outputs the representation, in binary and hexadecimal, of \f[B]x\f[R] as an unsigned integer in \f[B]2\f[R] bytes. Both outputs are split into bytes separated by spaces. .RS .PP If \f[B]x\f[R] is not an integer, is negative, or cannot fit into \f[B]2\f[R] bytes, an error message is printed instead, but bc(1) is not reset (see the \f[B]RESET\f[R] section). .PP This is a \f[B]void\f[R] function (see the \f[I]Void Functions\f[R] subsection of the \f[B]FUNCTIONS\f[R] section). .RE .TP \f[B]int16(x)\f[R] Outputs the representation, in binary and hexadecimal, of \f[B]x\f[R] as a signed, two\[cq]s-complement integer in \f[B]2\f[R] bytes. Both outputs are split into bytes separated by spaces. .RS .PP If \f[B]x\f[R] is not an integer or cannot fit into \f[B]2\f[R] bytes, an error message is printed instead, but bc(1) is not reset (see the \f[B]RESET\f[R] section). .PP This is a \f[B]void\f[R] function (see the \f[I]Void Functions\f[R] subsection of the \f[B]FUNCTIONS\f[R] section). .RE .TP \f[B]uint32(x)\f[R] Outputs the representation, in binary and hexadecimal, of \f[B]x\f[R] as an unsigned integer in \f[B]4\f[R] bytes. Both outputs are split into bytes separated by spaces. .RS .PP If \f[B]x\f[R] is not an integer, is negative, or cannot fit into \f[B]4\f[R] bytes, an error message is printed instead, but bc(1) is not reset (see the \f[B]RESET\f[R] section). .PP This is a \f[B]void\f[R] function (see the \f[I]Void Functions\f[R] subsection of the \f[B]FUNCTIONS\f[R] section). .RE .TP \f[B]int32(x)\f[R] Outputs the representation, in binary and hexadecimal, of \f[B]x\f[R] as a signed, two\[cq]s-complement integer in \f[B]4\f[R] bytes. Both outputs are split into bytes separated by spaces. .RS .PP If \f[B]x\f[R] is not an integer or cannot fit into \f[B]4\f[R] bytes, an error message is printed instead, but bc(1) is not reset (see the \f[B]RESET\f[R] section). .PP This is a \f[B]void\f[R] function (see the \f[I]Void Functions\f[R] subsection of the \f[B]FUNCTIONS\f[R] section). .RE .TP \f[B]uint64(x)\f[R] Outputs the representation, in binary and hexadecimal, of \f[B]x\f[R] as an unsigned integer in \f[B]8\f[R] bytes. Both outputs are split into bytes separated by spaces. .RS .PP If \f[B]x\f[R] is not an integer, is negative, or cannot fit into \f[B]8\f[R] bytes, an error message is printed instead, but bc(1) is not reset (see the \f[B]RESET\f[R] section). .PP This is a \f[B]void\f[R] function (see the \f[I]Void Functions\f[R] subsection of the \f[B]FUNCTIONS\f[R] section). .RE .TP \f[B]int64(x)\f[R] Outputs the representation, in binary and hexadecimal, of \f[B]x\f[R] as a signed, two\[cq]s-complement integer in \f[B]8\f[R] bytes. Both outputs are split into bytes separated by spaces. .RS .PP If \f[B]x\f[R] is not an integer or cannot fit into \f[B]8\f[R] bytes, an error message is printed instead, but bc(1) is not reset (see the \f[B]RESET\f[R] section). .PP This is a \f[B]void\f[R] function (see the \f[I]Void Functions\f[R] subsection of the \f[B]FUNCTIONS\f[R] section). .RE .TP \f[B]hex_uint(x, n)\f[R] Outputs the representation of the truncated absolute value of \f[B]x\f[R] as an unsigned integer in hexadecimal using \f[B]n\f[R] bytes. Not all of the value will be output if \f[B]n\f[R] is too small. .RS .PP This is a \f[B]void\f[R] function (see the \f[I]Void Functions\f[R] subsection of the \f[B]FUNCTIONS\f[R] section). .RE .TP \f[B]binary_uint(x, n)\f[R] Outputs the representation of the truncated absolute value of \f[B]x\f[R] as an unsigned integer in binary using \f[B]n\f[R] bytes. Not all of the value will be output if \f[B]n\f[R] is too small. .RS .PP This is a \f[B]void\f[R] function (see the \f[I]Void Functions\f[R] subsection of the \f[B]FUNCTIONS\f[R] section). .RE .TP \f[B]output_uint(x, n)\f[R] Outputs the representation of the truncated absolute value of \f[B]x\f[R] as an unsigned integer in the current \f[B]obase\f[R] (see the \f[B]SYNTAX\f[R] section) using \f[B]n\f[R] bytes. Not all of the value will be output if \f[B]n\f[R] is too small. .RS .PP This is a \f[B]void\f[R] function (see the \f[I]Void Functions\f[R] subsection of the \f[B]FUNCTIONS\f[R] section). .RE .TP \f[B]output_byte(x, i)\f[R] Outputs byte \f[B]i\f[R] of the truncated absolute value of \f[B]x\f[R], where \f[B]0\f[R] is the least significant byte and \f[B]number_of_bytes - 1\f[R] is the most significant byte. .RS .PP This is a \f[B]void\f[R] function (see the \f[I]Void Functions\f[R] subsection of the \f[B]FUNCTIONS\f[R] section). .RE .SS Transcendental Functions .PP All transcendental functions can return slightly inaccurate results (up to 1 ULP (https://en.wikipedia.org/wiki/Unit_in_the_last_place)). This is unavoidable, and this article (https://people.eecs.berkeley.edu/~wkahan/LOG10HAF.TXT) explains why it is impossible and unnecessary to calculate exact results for the transcendental functions. .PP Because of the possible inaccuracy, I recommend that users call those functions with the precision (\f[B]scale\f[R]) set to at least 1 higher than is necessary. If exact results are \f[I]absolutely\f[R] required, users can double the precision (\f[B]scale\f[R]) and then truncate. .PP The transcendental functions in the standard math library are: .IP \[bu] 2 \f[B]s(x)\f[R] .IP \[bu] 2 \f[B]c(x)\f[R] .IP \[bu] 2 \f[B]a(x)\f[R] .IP \[bu] 2 \f[B]l(x)\f[R] .IP \[bu] 2 \f[B]e(x)\f[R] .IP \[bu] 2 \f[B]j(x, n)\f[R] .PP The transcendental functions in the extended math library are: .IP \[bu] 2 \f[B]l2(x)\f[R] .IP \[bu] 2 \f[B]l10(x)\f[R] .IP \[bu] 2 \f[B]log(x, b)\f[R] .IP \[bu] 2 \f[B]pi(p)\f[R] .IP \[bu] 2 \f[B]t(x)\f[R] .IP \[bu] 2 \f[B]a2(y, x)\f[R] .IP \[bu] 2 \f[B]sin(x)\f[R] .IP \[bu] 2 \f[B]cos(x)\f[R] .IP \[bu] 2 \f[B]tan(x)\f[R] .IP \[bu] 2 \f[B]atan(x)\f[R] .IP \[bu] 2 \f[B]atan2(y, x)\f[R] .IP \[bu] 2 \f[B]r2d(x)\f[R] .IP \[bu] 2 \f[B]d2r(x)\f[R] .SH RESET .PP When bc(1) encounters an error or a signal that it has a non-default handler for, it resets. This means that several things happen. .PP First, any functions that are executing are stopped and popped off the stack. The behavior is not unlike that of exceptions in programming languages. Then the execution point is set so that any code waiting to execute (after all functions returned) is skipped. .PP Thus, when bc(1) resets, it skips any remaining code waiting to be executed. Then, if it is interactive mode, and the error was not a fatal error (see the \f[B]EXIT STATUS\f[R] section), it asks for more input; otherwise, it exits with the appropriate return code. .PP Note that this reset behavior is different from the GNU bc(1), which attempts to start executing the statement right after the one that caused an error. .SH PERFORMANCE .PP Most bc(1) implementations use \f[B]char\f[R] types to calculate the value of \f[B]1\f[R] decimal digit at a time, but that can be slow. This bc(1) does something different. .PP It uses large integers to calculate more than \f[B]1\f[R] decimal digit at a time. If built in a environment where \f[B]BC_LONG_BIT\f[R] (see the \f[B]LIMITS\f[R] section) is \f[B]64\f[R], then each integer has \f[B]9\f[R] decimal digits. If built in an environment where \f[B]BC_LONG_BIT\f[R] is \f[B]32\f[R] then each integer has \f[B]4\f[R] decimal digits. This value (the number of decimal digits per large integer) is called \f[B]BC_BASE_DIGS\f[R]. .PP The actual values of \f[B]BC_LONG_BIT\f[R] and \f[B]BC_BASE_DIGS\f[R] can be queried with the \f[B]limits\f[R] statement. .PP In addition, this bc(1) uses an even larger integer for overflow checking. This integer type depends on the value of \f[B]BC_LONG_BIT\f[R], but is always at least twice as large as the integer type used to store digits. .SH LIMITS .PP The following are the limits on bc(1): .TP \f[B]BC_LONG_BIT\f[R] The number of bits in the \f[B]long\f[R] type in the environment where bc(1) was built. This determines how many decimal digits can be stored in a single large integer (see the \f[B]PERFORMANCE\f[R] section). .TP \f[B]BC_BASE_DIGS\f[R] The number of decimal digits per large integer (see the \f[B]PERFORMANCE\f[R] section). Depends on \f[B]BC_LONG_BIT\f[R]. .TP \f[B]BC_BASE_POW\f[R] The max decimal number that each large integer can store (see \f[B]BC_BASE_DIGS\f[R]) plus \f[B]1\f[R]. Depends on \f[B]BC_BASE_DIGS\f[R]. .TP \f[B]BC_OVERFLOW_MAX\f[R] The max number that the overflow type (see the \f[B]PERFORMANCE\f[R] section) can hold. Depends on \f[B]BC_LONG_BIT\f[R]. .TP \f[B]BC_BASE_MAX\f[R] The maximum output base. Set at \f[B]BC_BASE_POW\f[R]. .TP \f[B]BC_DIM_MAX\f[R] The maximum size of arrays. Set at \f[B]SIZE_MAX-1\f[R]. .TP \f[B]BC_SCALE_MAX\f[R] The maximum \f[B]scale\f[R]. Set at \f[B]BC_OVERFLOW_MAX-1\f[R]. .TP \f[B]BC_STRING_MAX\f[R] The maximum length of strings. Set at \f[B]BC_OVERFLOW_MAX-1\f[R]. .TP \f[B]BC_NAME_MAX\f[R] The maximum length of identifiers. Set at \f[B]BC_OVERFLOW_MAX-1\f[R]. .TP \f[B]BC_NUM_MAX\f[R] The maximum length of a number (in decimal digits), which includes digits after the decimal point. Set at \f[B]BC_OVERFLOW_MAX-1\f[R]. .TP \f[B]BC_RAND_MAX\f[R] The maximum integer (inclusive) returned by the \f[B]rand()\f[R] operand. Set at \f[B]2\[ha]BC_LONG_BIT-1\f[R]. .TP Exponent The maximum allowable exponent (positive or negative). Set at \f[B]BC_OVERFLOW_MAX\f[R]. .TP Number of vars The maximum number of vars/arrays. Set at \f[B]SIZE_MAX-1\f[R]. .PP The actual values can be queried with the \f[B]limits\f[R] statement. .PP These limits are meant to be effectively non-existent; the limits are so large (at least on 64-bit machines) that there should not be any point at which they become a problem. In fact, memory should be exhausted before these limits should be hit. .SH ENVIRONMENT VARIABLES .PP bc(1) recognizes the following environment variables: .TP \f[B]POSIXLY_CORRECT\f[R] If this variable exists (no matter the contents), bc(1) behaves as if the \f[B]-s\f[R] option was given. .TP \f[B]BC_ENV_ARGS\f[R] This is another way to give command-line arguments to bc(1). They should be in the same format as all other command-line arguments. These are always processed first, so any files given in \f[B]BC_ENV_ARGS\f[R] will be processed before arguments and files given on the command-line. This gives the user the ability to set up \[lq]standard\[rq] options and files to be used at every invocation. The most useful thing for such files to contain would be useful functions that the user might want every time bc(1) runs. .RS .PP The code that parses \f[B]BC_ENV_ARGS\f[R] will correctly handle quoted arguments, but it does not understand escape sequences. For example, the string \f[B]\[lq]/home/gavin/some bc file.bc\[rq]\f[R] will be correctly parsed, but the string \f[B]\[lq]/home/gavin/some \[dq]bc\[dq] file.bc\[rq]\f[R] will include the backslashes. .PP The quote parsing will handle either kind of quotes, \f[B]\[cq]\f[R] or \f[B]\[lq]\f[R]. Thus, if you have a file with any number of single quotes in the name, you can use double quotes as the outside quotes, as in \f[B]\[lq]some `bc' file.bc\[rq]\f[R], and vice versa if you have a file with double quotes. However, handling a file with both kinds of quotes in \f[B]BC_ENV_ARGS\f[R] is not supported due to the complexity of the parsing, though such files are still supported on the command-line where the parsing is done by the shell. .RE .TP \f[B]BC_LINE_LENGTH\f[R] If this environment variable exists and contains an integer that is greater than \f[B]1\f[R] and is less than \f[B]UINT16_MAX\f[R] (\f[B]2\[ha]16-1\f[R]), bc(1) will output lines to that length, including the backslash (\f[B]\[rs]\f[R]). The default line length is \f[B]70\f[R]. .RS .PP The special value of \f[B]0\f[R] will disable line length checking and print numbers without regard to line length and without backslashes and newlines. .RE .TP \f[B]BC_BANNER\f[R] If this environment variable exists and contains an integer, then a non-zero value activates the copyright banner when bc(1) is in interactive mode, while zero deactivates it. .RS .PP If bc(1) is not in interactive mode (see the \f[B]INTERACTIVE MODE\f[R] section), then this environment variable has no effect because bc(1) does not print the banner when not in interactive mode. .PP This environment variable overrides the default, which can be queried with the \f[B]-h\f[R] or \f[B]--help\f[R] options. .RE .TP \f[B]BC_SIGINT_RESET\f[R] If bc(1) is not in interactive mode (see the \f[B]INTERACTIVE MODE\f[R] section), then this environment variable has no effect because bc(1) exits on \f[B]SIGINT\f[R] when not in interactive mode. .RS .PP However, when bc(1) is in interactive mode, then if this environment variable exists and contains an integer, a non-zero value makes bc(1) reset on \f[B]SIGINT\f[R], rather than exit, and zero makes bc(1) exit. If this environment variable exists and is \f[I]not\f[R] an integer, then bc(1) will exit on \f[B]SIGINT\f[R]. .PP This environment variable overrides the default, which can be queried with the \f[B]-h\f[R] or \f[B]--help\f[R] options. .RE .TP \f[B]BC_TTY_MODE\f[R] If TTY mode is \f[I]not\f[R] available (see the \f[B]TTY MODE\f[R] section), then this environment variable has no effect. .RS .PP However, when TTY mode is available, then if this environment variable exists and contains an integer, then a non-zero value makes bc(1) use TTY mode, and zero makes bc(1) not use TTY mode. .PP This environment variable overrides the default, which can be queried with the \f[B]-h\f[R] or \f[B]--help\f[R] options. .RE .TP \f[B]BC_PROMPT\f[R] If TTY mode is \f[I]not\f[R] available (see the \f[B]TTY MODE\f[R] section), then this environment variable has no effect. .RS .PP However, when TTY mode is available, then if this environment variable exists and contains an integer, a non-zero value makes bc(1) use a prompt, and zero or a non-integer makes bc(1) not use a prompt. If this environment variable does not exist and \f[B]BC_TTY_MODE\f[R] does, then the value of the \f[B]BC_TTY_MODE\f[R] environment variable is used. .PP This environment variable and the \f[B]BC_TTY_MODE\f[R] environment variable override the default, which can be queried with the \f[B]-h\f[R] or \f[B]--help\f[R] options. .RE +.TP +\f[B]BC_EXPR_EXIT\f[R] +If any expressions or expression files are given on the command-line +with \f[B]-e\f[R], \f[B]--expression\f[R], \f[B]-f\f[R], or +\f[B]--file\f[R], then if this environment variable exists and contains +an integer, a non-zero value makes bc(1) exit after executing the +expressions and expression files, and a non-zero value makes bc(1) not +exit. +.RS +.PP +This environment variable overrides the default, which can be queried +with the \f[B]-h\f[R] or \f[B]--help\f[R] options. +.RE .SH EXIT STATUS .PP bc(1) returns the following exit statuses: .TP \f[B]0\f[R] No error. .TP \f[B]1\f[R] A math error occurred. This follows standard practice of using \f[B]1\f[R] for expected errors, since math errors will happen in the process of normal execution. .RS .PP Math errors include divide by \f[B]0\f[R], taking the square root of a negative number, using a negative number as a bound for the pseudo-random number generator, attempting to convert a negative number to a hardware integer, overflow when converting a number to a hardware integer, overflow when calculating the size of a number, and attempting to use a non-integer where an integer is required. .PP Converting to a hardware integer happens for the second operand of the power (\f[B]\[ha]\f[R]), places (\f[B]\[at]\f[R]), left shift (\f[B]<<\f[R]), and right shift (\f[B]>>\f[R]) operators and their corresponding assignment operators. .RE .TP \f[B]2\f[R] A parse error occurred. .RS .PP Parse errors include unexpected \f[B]EOF\f[R], using an invalid character, failing to find the end of a string or comment, using a token where it is invalid, giving an invalid expression, giving an invalid print statement, giving an invalid function definition, attempting to assign to an expression that is not a named expression (see the \f[I]Named Expressions\f[R] subsection of the \f[B]SYNTAX\f[R] section), giving an invalid \f[B]auto\f[R] list, having a duplicate \f[B]auto\f[R]/function parameter, failing to find the end of a code block, attempting to return a value from a \f[B]void\f[R] function, attempting to use a variable as a reference, and using any extensions when the option \f[B]-s\f[R] or any equivalents were given. .RE .TP \f[B]3\f[R] A runtime error occurred. .RS .PP Runtime errors include assigning an invalid number to any global (\f[B]ibase\f[R], \f[B]obase\f[R], or \f[B]scale\f[R]), giving a bad expression to a \f[B]read()\f[R] call, calling \f[B]read()\f[R] inside of a \f[B]read()\f[R] call, type errors, passing the wrong number of arguments to functions, attempting to call an undefined function, and attempting to use a \f[B]void\f[R] function call as a value in an expression. .RE .TP \f[B]4\f[R] A fatal error occurred. .RS .PP Fatal errors include memory allocation errors, I/O errors, failing to open files, attempting to use files that do not have only ASCII characters (bc(1) only accepts ASCII characters), attempting to open a directory as a file, and giving invalid command-line options. .RE .PP The exit status \f[B]4\f[R] is special; when a fatal error occurs, bc(1) always exits and returns \f[B]4\f[R], no matter what mode bc(1) is in. .PP The other statuses will only be returned when bc(1) is not in interactive mode (see the \f[B]INTERACTIVE MODE\f[R] section), since bc(1) resets its state (see the \f[B]RESET\f[R] section) and accepts more input when one of those errors occurs in interactive mode. This is also the case when interactive mode is forced by the \f[B]-i\f[R] flag or \f[B]--interactive\f[R] option. .PP These exit statuses allow bc(1) to be used in shell scripting with error checking, and its normal behavior can be forced by using the \f[B]-i\f[R] flag or \f[B]--interactive\f[R] option. .SH INTERACTIVE MODE .PP Per the standard (https://pubs.opengroup.org/onlinepubs/9699919799/utilities/bc.html), bc(1) has an interactive mode and a non-interactive mode. Interactive mode is turned on automatically when both \f[B]stdin\f[R] and \f[B]stdout\f[R] are hooked to a terminal, but the \f[B]-i\f[R] flag and \f[B]--interactive\f[R] option can turn it on in other situations. .PP In interactive mode, bc(1) attempts to recover from errors (see the \f[B]RESET\f[R] section), and in normal execution, flushes \f[B]stdout\f[R] as soon as execution is done for the current input. bc(1) may also reset on \f[B]SIGINT\f[R] instead of exit, depending on the contents of, or default for, the \f[B]BC_SIGINT_RESET\f[R] environment variable (see the \f[B]ENVIRONMENT VARIABLES\f[R] section). .SH TTY MODE .PP If \f[B]stdin\f[R], \f[B]stdout\f[R], and \f[B]stderr\f[R] are all connected to a TTY, then \[lq]TTY mode\[rq] is considered to be available, and thus, bc(1) can turn on TTY mode, subject to some settings. .PP If there is the environment variable \f[B]BC_TTY_MODE\f[R] in the environment (see the \f[B]ENVIRONMENT VARIABLES\f[R] section), then if that environment variable contains a non-zero integer, bc(1) will turn on TTY mode when \f[B]stdin\f[R], \f[B]stdout\f[R], and \f[B]stderr\f[R] are all connected to a TTY. If the \f[B]BC_TTY_MODE\f[R] environment variable exists but is \f[I]not\f[R] a non-zero integer, then bc(1) will not turn TTY mode on. .PP If the environment variable \f[B]BC_TTY_MODE\f[R] does \f[I]not\f[R] exist, the default setting is used. The default setting can be queried with the \f[B]-h\f[R] or \f[B]--help\f[R] options. .PP TTY mode is different from interactive mode because interactive mode is required in the bc(1) specification (https://pubs.opengroup.org/onlinepubs/9699919799/utilities/bc.html), and interactive mode requires only \f[B]stdin\f[R] and \f[B]stdout\f[R] to be connected to a terminal. .SS Prompt .PP If TTY mode is available, then a prompt can be enabled. Like TTY mode itself, it can be turned on or off with an environment variable: \f[B]BC_PROMPT\f[R] (see the \f[B]ENVIRONMENT VARIABLES\f[R] section). .PP If the environment variable \f[B]BC_PROMPT\f[R] exists and is a non-zero integer, then the prompt is turned on when \f[B]stdin\f[R], \f[B]stdout\f[R], and \f[B]stderr\f[R] are connected to a TTY and the \f[B]-P\f[R] and \f[B]--no-prompt\f[R] options were not used. The read prompt will be turned on under the same conditions, except that the \f[B]-R\f[R] and \f[B]--no-read-prompt\f[R] options must also not be used. .PP However, if \f[B]BC_PROMPT\f[R] does not exist, the prompt can be enabled or disabled with the \f[B]BC_TTY_MODE\f[R] environment variable, the \f[B]-P\f[R] and \f[B]--no-prompt\f[R] options, and the \f[B]-R\f[R] and \f[B]--no-read-prompt\f[R] options. See the \f[B]ENVIRONMENT VARIABLES\f[R] and \f[B]OPTIONS\f[R] sections for more details. .SH SIGNAL HANDLING .PP Sending a \f[B]SIGINT\f[R] will cause bc(1) to do one of two things. .PP If bc(1) is not in interactive mode (see the \f[B]INTERACTIVE MODE\f[R] section), or the \f[B]BC_SIGINT_RESET\f[R] environment variable (see the \f[B]ENVIRONMENT VARIABLES\f[R] section), or its default, is either not an integer or it is zero, bc(1) will exit. .PP However, if bc(1) is in interactive mode, and the \f[B]BC_SIGINT_RESET\f[R] or its default is an integer and non-zero, then bc(1) will stop executing the current input and reset (see the \f[B]RESET\f[R] section) upon receiving a \f[B]SIGINT\f[R]. .PP Note that \[lq]current input\[rq] can mean one of two things. If bc(1) is processing input from \f[B]stdin\f[R] in interactive mode, it will ask for more input. If bc(1) is processing input from a file in interactive mode, it will stop processing the file and start processing the next file, if one exists, or ask for input from \f[B]stdin\f[R] if no other file exists. .PP This means that if a \f[B]SIGINT\f[R] is sent to bc(1) as it is executing a file, it can seem as though bc(1) did not respond to the signal since it will immediately start executing the next file. This is by design; most files that users execute when interacting with bc(1) have function definitions, which are quick to parse. If a file takes a long time to execute, there may be a bug in that file. The rest of the files could still be executed without problem, allowing the user to continue. .PP \f[B]SIGTERM\f[R] and \f[B]SIGQUIT\f[R] cause bc(1) to clean up and exit, and it uses the default handler for all other signals. .SH SEE ALSO .PP dc(1) .SH STANDARDS .PP bc(1) is compliant with the IEEE Std 1003.1-2017 (\[lq]POSIX.1-2017\[rq]) (https://pubs.opengroup.org/onlinepubs/9699919799/utilities/bc.html) specification. The flags \f[B]-efghiqsvVw\f[R], all long options, and the extensions noted above are extensions to that specification. .PP Note that the specification explicitly says that bc(1) only accepts numbers that use a period (\f[B].\f[R]) as a radix point, regardless of the value of \f[B]LC_NUMERIC\f[R]. .SH BUGS .PP None are known. Report bugs at https://git.yzena.com/gavin/bc. .SH AUTHORS .PP Gavin D. Howard and contributors. diff --git a/contrib/bc/manuals/bc/HN.1.md b/contrib/bc/manuals/bc/HN.1.md index d5b3324514ad..12ed1c9c5e74 100644 --- a/contrib/bc/manuals/bc/HN.1.md +++ b/contrib/bc/manuals/bc/HN.1.md @@ -1,2313 +1,2324 @@ # NAME bc - arbitrary-precision decimal arithmetic language and calculator # SYNOPSIS **bc** [**-ghilPqRsvVw**] [**-\-global-stacks**] [**-\-help**] [**-\-interactive**] [**-\-mathlib**] [**-\-no-prompt**] [**-\-no-read-prompt**] [**-\-quiet**] [**-\-standard**] [**-\-warn**] [**-\-version**] [**-e** *expr*] [**-\-expression**=*expr*...] [**-f** *file*...] [**-\-file**=*file*...] [*file*...] # DESCRIPTION bc(1) is an interactive processor for a language first standardized in 1991 by POSIX. (The current standard is [here][1].) The language provides unlimited precision decimal arithmetic and is somewhat C-like, but there are differences. Such differences will be noted in this document. After parsing and handling options, this bc(1) reads any files given on the command line and executes them before reading from **stdin**. This bc(1) is a drop-in replacement for *any* bc(1), including (and especially) the GNU bc(1). It also has many extensions and extra features beyond other implementations. **Note**: If running this bc(1) on *any* script meant for another bc(1) gives a parse error, it is probably because a word this bc(1) reserves as a keyword is used as the name of a function, variable, or array. To fix that, use the command-line option **-r** *keyword*, where *keyword* is the keyword that is used as a name in the script. For more information, see the **OPTIONS** section. If parsing scripts meant for other bc(1) implementations still does not work, that is a bug and should be reported. See the **BUGS** section. # OPTIONS The following are the options that bc(1) accepts. **-g**, **-\-global-stacks** : Turns the globals **ibase**, **obase**, **scale**, and **seed** into stacks. This has the effect that a copy of the current value of all four are pushed onto a stack for every function call, as well as popped when every function returns. This means that functions can assign to any and all of those globals without worrying that the change will affect other functions. Thus, a hypothetical function named **output(x,b)** that simply printed **x** in base **b** could be written like this: define void output(x, b) { obase=b x } instead of like this: define void output(x, b) { auto c c=obase obase=b x obase=c } This makes writing functions much easier. (**Note**: the function **output(x,b)** exists in the extended math library. See the **LIBRARY** section.) However, since using this flag means that functions cannot set **ibase**, **obase**, **scale**, or **seed** globally, functions that are made to do so cannot work anymore. There are two possible use cases for that, and each has a solution. First, if a function is called on startup to turn bc(1) into a number converter, it is possible to replace that capability with various shell aliases. Examples: alias d2o="bc -e ibase=A -e obase=8" alias h2b="bc -e ibase=G -e obase=2" Second, if the purpose of a function is to set **ibase**, **obase**, **scale**, or **seed** globally for any other purpose, it could be split into one to four functions (based on how many globals it sets) and each of those functions could return the desired value for a global. For functions that set **seed**, the value assigned to **seed** is not propagated to parent functions. This means that the sequence of pseudo-random numbers that they see will not be the same sequence of pseudo-random numbers that any parent sees. This is only the case once **seed** has been set. If a function desires to not affect the sequence of pseudo-random numbers of its parents, but wants to use the same **seed**, it can use the following line: seed = seed If the behavior of this option is desired for every run of bc(1), then users could make sure to define **BC_ENV_ARGS** and include this option (see the **ENVIRONMENT VARIABLES** section for more details). If **-s**, **-w**, or any equivalents are used, this option is ignored. This is a **non-portable extension**. **-h**, **-\-help** : Prints a usage message and quits. **-i**, **-\-interactive** : Forces interactive mode. (See the **INTERACTIVE MODE** section.) This is a **non-portable extension**. **-L**, **-\-no-line-length** : Disables line length checking and prints numbers without backslashes and newlines. In other words, this option sets **BC_LINE_LENGTH** to **0** (see the **ENVIRONMENT VARIABLES** section). This is a **non-portable extension**. **-l**, **-\-mathlib** : Sets **scale** (see the **SYNTAX** section) to **20** and loads the included math library and the extended math library before running any code, including any expressions or files specified on the command line. To learn what is in the libraries, see the **LIBRARY** section. **-P**, **-\-no-prompt** : Disables the prompt in TTY mode. (The prompt is only enabled in TTY mode. See the **TTY MODE** section.) This is mostly for those users that do not want a prompt or are not used to having them in bc(1). Most of those users would want to put this option in **BC_ENV_ARGS** (see the **ENVIRONMENT VARIABLES** section). These options override the **BC_PROMPT** and **BC_TTY_MODE** environment variables (see the **ENVIRONMENT VARIABLES** section). This is a **non-portable extension**. **-R**, **-\-no-read-prompt** : Disables the read prompt in TTY mode. (The read prompt is only enabled in TTY mode. See the **TTY MODE** section.) This is mostly for those users that do not want a read prompt or are not used to having them in bc(1). Most of those users would want to put this option in **BC_ENV_ARGS** (see the **ENVIRONMENT VARIABLES** section). This option is also useful in hash bang lines of bc(1) scripts that prompt for user input. This option does not disable the regular prompt because the read prompt is only used when the **read()** built-in function is called. These options *do* override the **BC_PROMPT** and **BC_TTY_MODE** environment variables (see the **ENVIRONMENT VARIABLES** section), but only for the read prompt. This is a **non-portable extension**. **-r** *keyword*, **-\-redefine**=*keyword* : Redefines *keyword* in order to allow it to be used as a function, variable, or array name. This is useful when this bc(1) gives parse errors when parsing scripts meant for other bc(1) implementations. The keywords this bc(1) allows to be redefined are: * **abs** * **asciify** * **continue** * **divmod** * **else** * **halt** * **irand** * **last** * **limits** * **maxibase** * **maxobase** * **maxrand** * **maxscale** * **modexp** * **print** * **rand** * **read** * **seed** * **stream** If any of those keywords are used as a function, variable, or array name in a script, use this option with the keyword as the argument. If multiple are used, use this option for all of them; it can be used multiple times. Keywords are *not* redefined when parsing the builtin math library (see the **LIBRARY** section). It is a fatal error to redefine keywords mandated by the POSIX standard. It is a fatal error to attempt to redefine words that this bc(1) does not reserve as keywords. **-q**, **-\-quiet** : This option is for compatibility with the [GNU bc(1)][2]; it is a no-op. Without this option, GNU bc(1) prints a copyright header. This bc(1) only prints the copyright header if one or more of the **-v**, **-V**, or **-\-version** options are given. This is a **non-portable extension**. **-s**, **-\-standard** : Process exactly the language defined by the [standard][1] and error if any extensions are used. This is a **non-portable extension**. **-v**, **-V**, **-\-version** : Print the version information (copyright header) and exit. This is a **non-portable extension**. **-w**, **-\-warn** : Like **-s** and **-\-standard**, except that warnings (and not errors) are printed for non-standard extensions and execution continues normally. This is a **non-portable extension**. **-z**, **-\-leading-zeroes** : Makes bc(1) print all numbers greater than **-1** and less than **1**, and not equal to **0**, with a leading zero. This can be set for individual numbers with the **plz(x)**, plznl(x)**, **pnlz(x)**, and **pnlznl(x)** functions in the extended math library (see the **LIBRARY** section). This is a **non-portable extension**. **-e** *expr*, **-\-expression**=*expr* : Evaluates *expr*. If multiple expressions are given, they are evaluated in order. If files are given as well (see below), the expressions and files are evaluated in the order given. This means that if a file is given before an expression, the file is read in and evaluated first. If this option is given on the command-line (i.e., not in **BC_ENV_ARGS**, see the **ENVIRONMENT VARIABLES** section), then after processing all expressions and files, bc(1) will exit, unless **-** (**stdin**) was given as an argument at least once to **-f** or **-\-file**, whether on the command-line or in **BC_ENV_ARGS**. However, if any other **-e**, **-\-expression**, **-f**, or **-\-file** arguments are given after **-f-** or equivalent is given, bc(1) will give a fatal error and exit. This is a **non-portable extension**. **-f** *file*, **-\-file**=*file* : Reads in *file* and evaluates it, line by line, as though it were read through **stdin**. If expressions are also given (see above), the expressions are evaluated in the order given. If this option is given on the command-line (i.e., not in **BC_ENV_ARGS**, see the **ENVIRONMENT VARIABLES** section), then after processing all expressions and files, bc(1) will exit, unless **-** (**stdin**) was given as an argument at least once to **-f** or **-\-file**. However, if any other **-e**, **-\-expression**, **-f**, or **-\-file** arguments are given after **-f-** or equivalent is given, bc(1) will give a fatal error and exit. This is a **non-portable extension**. All long options are **non-portable extensions**. # STDIN If no files or expressions are given by the **-f**, **-\-file**, **-e**, or **-\-expression** options, then bc(1) read from **stdin**. However, there are a few caveats to this. First, **stdin** is evaluated a line at a time. The only exception to this is if the parse cannot complete. That means that starting a string without ending it or starting a function, **if** statement, or loop without ending it will also cause bc(1) to not execute. Second, after an **if** statement, bc(1) doesn't know if an **else** statement will follow, so it will not execute until it knows there will not be an **else** statement. # STDOUT Any non-error output is written to **stdout**. In addition, if history (see the **HISTORY** section) and the prompt (see the **TTY MODE** section) are enabled, both are output to **stdout**. **Note**: Unlike other bc(1) implementations, this bc(1) will issue a fatal error (see the **EXIT STATUS** section) if it cannot write to **stdout**, so if **stdout** is closed, as in **bc >&-**, it will quit with an error. This is done so that bc(1) can report problems when **stdout** is redirected to a file. If there are scripts that depend on the behavior of other bc(1) implementations, it is recommended that those scripts be changed to redirect **stdout** to **/dev/null**. # STDERR Any error output is written to **stderr**. **Note**: Unlike other bc(1) implementations, this bc(1) will issue a fatal error (see the **EXIT STATUS** section) if it cannot write to **stderr**, so if **stderr** is closed, as in **bc 2>&-**, it will quit with an error. This is done so that bc(1) can exit with an error code when **stderr** is redirected to a file. If there are scripts that depend on the behavior of other bc(1) implementations, it is recommended that those scripts be changed to redirect **stderr** to **/dev/null**. # SYNTAX The syntax for bc(1) programs is mostly C-like, with some differences. This bc(1) follows the [POSIX standard][1], which is a much more thorough resource for the language this bc(1) accepts. This section is meant to be a summary and a listing of all the extensions to the standard. In the sections below, **E** means expression, **S** means statement, and **I** means identifier. Identifiers (**I**) start with a lowercase letter and can be followed by any number (up to **BC_NAME_MAX-1**) of lowercase letters (**a-z**), digits (**0-9**), and underscores (**\_**). The regex is **\[a-z\]\[a-z0-9\_\]\***. Identifiers with more than one character (letter) are a **non-portable extension**. **ibase** is a global variable determining how to interpret constant numbers. It is the "input" base, or the number base used for interpreting input numbers. **ibase** is initially **10**. If the **-s** (**-\-standard**) and **-w** (**-\-warn**) flags were not given on the command line, the max allowable value for **ibase** is **36**. Otherwise, it is **16**. The min allowable value for **ibase** is **2**. The max allowable value for **ibase** can be queried in bc(1) programs with the **maxibase()** built-in function. **obase** is a global variable determining how to output results. It is the "output" base, or the number base used for outputting numbers. **obase** is initially **10**. The max allowable value for **obase** is **BC_BASE_MAX** and can be queried in bc(1) programs with the **maxobase()** built-in function. The min allowable value for **obase** is **0**. If **obase** is **0**, values are output in scientific notation, and if **obase** is **1**, values are output in engineering notation. Otherwise, values are output in the specified base. Outputting in scientific and engineering notations are **non-portable extensions**. The *scale* of an expression is the number of digits in the result of the expression right of the decimal point, and **scale** is a global variable that sets the precision of any operations, with exceptions. **scale** is initially **0**. **scale** cannot be negative. The max allowable value for **scale** is **BC_SCALE_MAX** and can be queried in bc(1) programs with the **maxscale()** built-in function. bc(1) has both *global* variables and *local* variables. All *local* variables are local to the function; they are parameters or are introduced in the **auto** list of a function (see the **FUNCTIONS** section). If a variable is accessed which is not a parameter or in the **auto** list, it is assumed to be *global*. If a parent function has a *local* variable version of a variable that a child function considers *global*, the value of that *global* variable in the child function is the value of the variable in the parent function, not the value of the actual *global* variable. All of the above applies to arrays as well. The value of a statement that is an expression (i.e., any of the named expressions or operands) is printed unless the lowest precedence operator is an assignment operator *and* the expression is notsurrounded by parentheses. The value that is printed is also assigned to the special variable **last**. A single dot (**.**) may also be used as a synonym for **last**. These are **non-portable extensions**. Either semicolons or newlines may separate statements. ## Comments There are two kinds of comments: 1. Block comments are enclosed in **/\*** and **\*/**. 2. Line comments go from **#** until, and not including, the next newline. This is a **non-portable extension**. ## Named Expressions The following are named expressions in bc(1): 1. Variables: **I** 2. Array Elements: **I[E]** 3. **ibase** 4. **obase** 5. **scale** 6. **seed** 7. **last** or a single dot (**.**) Numbers 6 and 7 are **non-portable extensions**. The meaning of **seed** is dependent on the current pseudo-random number generator but is guaranteed to not change except for new major versions. The *scale* and sign of the value may be significant. If a previously used **seed** value is assigned to **seed** and used again, the pseudo-random number generator is guaranteed to produce the same sequence of pseudo-random numbers as it did when the **seed** value was previously used. The exact value assigned to **seed** is not guaranteed to be returned if **seed** is queried again immediately. However, if **seed** *does* return a different value, both values, when assigned to **seed**, are guaranteed to produce the same sequence of pseudo-random numbers. This means that certain values assigned to **seed** will *not* produce unique sequences of pseudo-random numbers. The value of **seed** will change after any use of the **rand()** and **irand(E)** operands (see the *Operands* subsection below), except if the parameter passed to **irand(E)** is **0**, **1**, or negative. There is no limit to the length (number of significant decimal digits) or *scale* of the value that can be assigned to **seed**. Variables and arrays do not interfere; users can have arrays named the same as variables. This also applies to functions (see the **FUNCTIONS** section), so a user can have a variable, array, and function that all have the same name, and they will not shadow each other, whether inside of functions or not. Named expressions are required as the operand of **increment**/**decrement** operators and as the left side of **assignment** operators (see the *Operators* subsection). ## Operands The following are valid operands in bc(1): 1. Numbers (see the *Numbers* subsection below). 2. Array indices (**I[E]**). 3. **(E)**: The value of **E** (used to change precedence). 4. **sqrt(E)**: The square root of **E**. **E** must be non-negative. 5. **length(E)**: The number of significant decimal digits in **E**. Returns **1** for **0** with no decimal places. If given a string, the length of the string is returned. Passing a string to **length(E)** is a **non-portable extension**. 6. **length(I[])**: The number of elements in the array **I**. This is a **non-portable extension**. 7. **scale(E)**: The *scale* of **E**. 8. **abs(E)**: The absolute value of **E**. This is a **non-portable extension**. 9. **modexp(E, E, E)**: Modular exponentiation, where the first expression is the base, the second is the exponent, and the third is the modulus. All three values must be integers. The second argument must be non-negative. The third argument must be non-zero. This is a **non-portable extension**. 10. **divmod(E, E, I[])**: Division and modulus in one operation. This is for optimization. The first expression is the dividend, and the second is the divisor, which must be non-zero. The return value is the quotient, and the modulus is stored in index **0** of the provided array (the last argument). This is a **non-portable extension**. 11. **asciify(E)**: If **E** is a string, returns a string that is the first letter of its argument. If it is a number, calculates the number mod **256** and returns that number as a one-character string. This is a **non-portable extension**. 12. **I()**, **I(E)**, **I(E, E)**, and so on, where **I** is an identifier for a non-**void** function (see the *Void Functions* subsection of the **FUNCTIONS** section). The **E** argument(s) may also be arrays of the form **I[]**, which will automatically be turned into array references (see the *Array References* subsection of the **FUNCTIONS** section) if the corresponding parameter in the function definition is an array reference. 13. **read()**: Reads a line from **stdin** and uses that as an expression. The result of that expression is the result of the **read()** operand. This is a **non-portable extension**. 14. **maxibase()**: The max allowable **ibase**. This is a **non-portable extension**. 15. **maxobase()**: The max allowable **obase**. This is a **non-portable extension**. 16. **maxscale()**: The max allowable **scale**. This is a **non-portable extension**. 17. **line_length()**: The line length set with **BC_LINE_LENGTH** (see the **ENVIRONMENT VARIABLES** section). This is a **non-portable extension**. 18. **global_stacks()**: **0** if global stacks are not enabled with the **-g** or **-\-global-stacks** options, non-zero otherwise. See the **OPTIONS** section. This is a **non-portable extension**. 19. **leading_zero()**: **0** if leading zeroes are not enabled with the **-z** or **--leading-zeroes** options, non-zero otherwise. See the **OPTIONS** section. This is a **non-portable extension**. 20. **rand()**: A pseudo-random integer between **0** (inclusive) and **BC_RAND_MAX** (inclusive). Using this operand will change the value of **seed**. This is a **non-portable extension**. 21. **irand(E)**: A pseudo-random integer between **0** (inclusive) and the value of **E** (exclusive). If **E** is negative or is a non-integer (**E**'s *scale* is not **0**), an error is raised, and bc(1) resets (see the **RESET** section) while **seed** remains unchanged. If **E** is larger than **BC_RAND_MAX**, the higher bound is honored by generating several pseudo-random integers, multiplying them by appropriate powers of **BC_RAND_MAX+1**, and adding them together. Thus, the size of integer that can be generated with this operand is unbounded. Using this operand will change the value of **seed**, unless the value of **E** is **0** or **1**. In that case, **0** is returned, and **seed** is *not* changed. This is a **non-portable extension**. 22. **maxrand()**: The max integer returned by **rand()**. This is a **non-portable extension**. The integers generated by **rand()** and **irand(E)** are guaranteed to be as unbiased as possible, subject to the limitations of the pseudo-random number generator. **Note**: The values returned by the pseudo-random number generator with **rand()** and **irand(E)** are guaranteed to *NOT* be cryptographically secure. This is a consequence of using a seeded pseudo-random number generator. However, they *are* guaranteed to be reproducible with identical **seed** values. This means that the pseudo-random values from bc(1) should only be used where a reproducible stream of pseudo-random numbers is *ESSENTIAL*. In any other case, use a non-seeded pseudo-random number generator. ## Numbers Numbers are strings made up of digits, uppercase letters, and at most **1** period for a radix. Numbers can have up to **BC_NUM_MAX** digits. Uppercase letters are equal to **9** + their position in the alphabet (i.e., **A** equals **10**, or **9+1**). If a digit or letter makes no sense with the current value of **ibase**, they are set to the value of the highest valid digit in **ibase**. Single-character numbers (i.e., **A** alone) take the value that they would have if they were valid digits, regardless of the value of **ibase**. This means that **A** alone always equals decimal **10** and **Z** alone always equals decimal **35**. In addition, bc(1) accepts numbers in scientific notation. These have the form **\e\**. The exponent (the portion after the **e**) must be an integer. An example is **1.89237e9**, which is equal to **1892370000**. Negative exponents are also allowed, so **4.2890e-3** is equal to **0.0042890**. Using scientific notation is an error or warning if the **-s** or **-w**, respectively, command-line options (or equivalents) are given. **WARNING**: Both the number and the exponent in scientific notation are interpreted according to the current **ibase**, but the number is still multiplied by **10\^exponent** regardless of the current **ibase**. For example, if **ibase** is **16** and bc(1) is given the number string **FFeA**, the resulting decimal number will be **2550000000000**, and if bc(1) is given the number string **10e-4**, the resulting decimal number will be **0.0016**. Accepting input as scientific notation is a **non-portable extension**. ## Operators The following arithmetic and logical operators can be used. They are listed in order of decreasing precedence. Operators in the same group have the same precedence. **++** **-\-** : Type: Prefix and Postfix Associativity: None Description: **increment**, **decrement** **-** **!** : Type: Prefix Associativity: None Description: **negation**, **boolean not** **\$** : Type: Postfix Associativity: None Description: **truncation** **\@** : Type: Binary Associativity: Right Description: **set precision** **\^** : Type: Binary Associativity: Right Description: **power** **\*** **/** **%** : Type: Binary Associativity: Left Description: **multiply**, **divide**, **modulus** **+** **-** : Type: Binary Associativity: Left Description: **add**, **subtract** **\<\<** **\>\>** : Type: Binary Associativity: Left Description: **shift left**, **shift right** **=** **\<\<=** **\>\>=** **+=** **-=** **\*=** **/=** **%=** **\^=** **\@=** : Type: Binary Associativity: Right Description: **assignment** **==** **\<=** **\>=** **!=** **\<** **\>** : Type: Binary Associativity: Left Description: **relational** **&&** : Type: Binary Associativity: Left Description: **boolean and** **||** : Type: Binary Associativity: Left Description: **boolean or** The operators will be described in more detail below. **++** **-\-** : The prefix and postfix **increment** and **decrement** operators behave exactly like they would in C. They require a named expression (see the *Named Expressions* subsection) as an operand. The prefix versions of these operators are more efficient; use them where possible. **-** : The **negation** operator returns **0** if a user attempts to negate any expression with the value **0**. Otherwise, a copy of the expression with its sign flipped is returned. **!** : The **boolean not** operator returns **1** if the expression is **0**, or **0** otherwise. This is a **non-portable extension**. **\$** : The **truncation** operator returns a copy of the given expression with all of its *scale* removed. This is a **non-portable extension**. **\@** : The **set precision** operator takes two expressions and returns a copy of the first with its *scale* equal to the value of the second expression. That could either mean that the number is returned without change (if the *scale* of the first expression matches the value of the second expression), extended (if it is less), or truncated (if it is more). The second expression must be an integer (no *scale*) and non-negative. This is a **non-portable extension**. **\^** : The **power** operator (not the **exclusive or** operator, as it would be in C) takes two expressions and raises the first to the power of the value of the second. The *scale* of the result is equal to **scale**. The second expression must be an integer (no *scale*), and if it is negative, the first value must be non-zero. **\*** : The **multiply** operator takes two expressions, multiplies them, and returns the product. If **a** is the *scale* of the first expression and **b** is the *scale* of the second expression, the *scale* of the result is equal to **min(a+b,max(scale,a,b))** where **min()** and **max()** return the obvious values. **/** : The **divide** operator takes two expressions, divides them, and returns the quotient. The *scale* of the result shall be the value of **scale**. The second expression must be non-zero. **%** : The **modulus** operator takes two expressions, **a** and **b**, and evaluates them by 1) Computing **a/b** to current **scale** and 2) Using the result of step 1 to calculate **a-(a/b)\*b** to *scale* **max(scale+scale(b),scale(a))**. The second expression must be non-zero. **+** : The **add** operator takes two expressions, **a** and **b**, and returns the sum, with a *scale* equal to the max of the *scale*s of **a** and **b**. **-** : The **subtract** operator takes two expressions, **a** and **b**, and returns the difference, with a *scale* equal to the max of the *scale*s of **a** and **b**. **\<\<** : The **left shift** operator takes two expressions, **a** and **b**, and returns a copy of the value of **a** with its decimal point moved **b** places to the right. The second expression must be an integer (no *scale*) and non-negative. This is a **non-portable extension**. **\>\>** : The **right shift** operator takes two expressions, **a** and **b**, and returns a copy of the value of **a** with its decimal point moved **b** places to the left. The second expression must be an integer (no *scale*) and non-negative. This is a **non-portable extension**. **=** **\<\<=** **\>\>=** **+=** **-=** **\*=** **/=** **%=** **\^=** **\@=** : The **assignment** operators take two expressions, **a** and **b** where **a** is a named expression (see the *Named Expressions* subsection). For **=**, **b** is copied and the result is assigned to **a**. For all others, **a** and **b** are applied as operands to the corresponding arithmetic operator and the result is assigned to **a**. The **assignment** operators that correspond to operators that are extensions are themselves **non-portable extensions**. **==** **\<=** **\>=** **!=** **\<** **\>** : The **relational** operators compare two expressions, **a** and **b**, and if the relation holds, according to C language semantics, the result is **1**. Otherwise, it is **0**. Note that unlike in C, these operators have a lower precedence than the **assignment** operators, which means that **a=b\>c** is interpreted as **(a=b)\>c**. Also, unlike the [standard][1] requires, these operators can appear anywhere any other expressions can be used. This allowance is a **non-portable extension**. **&&** : The **boolean and** operator takes two expressions and returns **1** if both expressions are non-zero, **0** otherwise. This is *not* a short-circuit operator. This is a **non-portable extension**. **||** : The **boolean or** operator takes two expressions and returns **1** if one of the expressions is non-zero, **0** otherwise. This is *not* a short-circuit operator. This is a **non-portable extension**. ## Statements The following items are statements: 1. **E** 2. **{** **S** **;** ... **;** **S** **}** 3. **if** **(** **E** **)** **S** 4. **if** **(** **E** **)** **S** **else** **S** 5. **while** **(** **E** **)** **S** 6. **for** **(** **E** **;** **E** **;** **E** **)** **S** 7. An empty statement 8. **break** 9. **continue** 10. **quit** 11. **halt** 12. **limits** 13. A string of characters, enclosed in double quotes 14. **print** **E** **,** ... **,** **E** 15. **stream** **E** **,** ... **,** **E** 16. **I()**, **I(E)**, **I(E, E)**, and so on, where **I** is an identifier for a **void** function (see the *Void Functions* subsection of the **FUNCTIONS** section). The **E** argument(s) may also be arrays of the form **I[]**, which will automatically be turned into array references (see the *Array References* subsection of the **FUNCTIONS** section) if the corresponding parameter in the function definition is an array reference. Numbers 4, 9, 11, 12, 14, 15, and 16 are **non-portable extensions**. Also, as a **non-portable extension**, any or all of the expressions in the header of a for loop may be omitted. If the condition (second expression) is omitted, it is assumed to be a constant **1**. The **break** statement causes a loop to stop iterating and resume execution immediately following a loop. This is only allowed in loops. The **continue** statement causes a loop iteration to stop early and returns to the start of the loop, including testing the loop condition. This is only allowed in loops. The **if** **else** statement does the same thing as in C. The **quit** statement causes bc(1) to quit, even if it is on a branch that will not be executed (it is a compile-time command). The **halt** statement causes bc(1) to quit, if it is executed. (Unlike **quit** if it is on a branch of an **if** statement that is not executed, bc(1) does not quit.) The **limits** statement prints the limits that this bc(1) is subject to. This is like the **quit** statement in that it is a compile-time command. An expression by itself is evaluated and printed, followed by a newline. Both scientific notation and engineering notation are available for printing the results of expressions. Scientific notation is activated by assigning **0** to **obase**, and engineering notation is activated by assigning **1** to **obase**. To deactivate them, just assign a different value to **obase**. Scientific notation and engineering notation are disabled if bc(1) is run with either the **-s** or **-w** command-line options (or equivalents). Printing numbers in scientific notation and/or engineering notation is a **non-portable extension**. ## Strings If strings appear as a statement by themselves, they are printed without a trailing newline. In addition to appearing as a lone statement by themselves, strings can be assigned to variables and array elements. They can also be passed to functions in variable parameters. If any statement that expects a string is given a variable that had a string assigned to it, the statement acts as though it had received a string. If any math operation is attempted on a string or a variable or array element that has been assigned a string, an error is raised, and bc(1) resets (see the **RESET** section). Assigning strings to variables and array elements and passing them to functions are **non-portable extensions**. ## Print Statement The "expressions" in a **print** statement may also be strings. If they are, there are backslash escape sequences that are interpreted specially. What those sequences are, and what they cause to be printed, are shown below: **\\a**: **\\a** **\\b**: **\\b** **\\\\**: **\\** **\\e**: **\\** **\\f**: **\\f** **\\n**: **\\n** **\\q**: **"** **\\r**: **\\r** **\\t**: **\\t** Any other character following a backslash causes the backslash and character to be printed as-is. Any non-string expression in a print statement shall be assigned to **last**, like any other expression that is printed. ## Stream Statement The "expressions in a **stream** statement may also be strings. If a **stream** statement is given a string, it prints the string as though the string had appeared as its own statement. In other words, the **stream** statement prints strings normally, without a newline. If a **stream** statement is given a number, a copy of it is truncated and its absolute value is calculated. The result is then printed as though **obase** is **256** and each digit is interpreted as an 8-bit ASCII character, making it a byte stream. ## Order of Evaluation All expressions in a statment are evaluated left to right, except as necessary to maintain order of operations. This means, for example, assuming that **i** is equal to **0**, in the expression a[i++] = i++ the first (or 0th) element of **a** is set to **1**, and **i** is equal to **2** at the end of the expression. This includes function arguments. Thus, assuming **i** is equal to **0**, this means that in the expression x(i++, i++) the first argument passed to **x()** is **0**, and the second argument is **1**, while **i** is equal to **2** before the function starts executing. # FUNCTIONS Function definitions are as follows: ``` define I(I,...,I){ auto I,...,I S;...;S return(E) } ``` Any **I** in the parameter list or **auto** list may be replaced with **I[]** to make a parameter or **auto** var an array, and any **I** in the parameter list may be replaced with **\*I[]** to make a parameter an array reference. Callers of functions that take array references should not put an asterisk in the call; they must be called with just **I[]** like normal array parameters and will be automatically converted into references. As a **non-portable extension**, the opening brace of a **define** statement may appear on the next line. As a **non-portable extension**, the return statement may also be in one of the following forms: 1. **return** 2. **return** **(** **)** 3. **return** **E** The first two, or not specifying a **return** statement, is equivalent to **return (0)**, unless the function is a **void** function (see the *Void Functions* subsection below). ## Void Functions Functions can also be **void** functions, defined as follows: ``` define void I(I,...,I){ auto I,...,I S;...;S return } ``` They can only be used as standalone expressions, where such an expression would be printed alone, except in a print statement. Void functions can only use the first two **return** statements listed above. They can also omit the return statement entirely. The word "void" is not treated as a keyword; it is still possible to have variables, arrays, and functions named **void**. The word "void" is only treated specially right after the **define** keyword. This is a **non-portable extension**. ## Array References For any array in the parameter list, if the array is declared in the form ``` *I[] ``` it is a **reference**. Any changes to the array in the function are reflected, when the function returns, to the array that was passed in. Other than this, all function arguments are passed by value. This is a **non-portable extension**. # LIBRARY All of the functions below, including the functions in the extended math library (see the *Extended Library* subsection below), are available when the **-l** or **-\-mathlib** command-line flags are given, except that the extended math library is not available when the **-s** option, the **-w** option, or equivalents are given. ## Standard Library The [standard][1] defines the following functions for the math library: **s(x)** : Returns the sine of **x**, which is assumed to be in radians. This is a transcendental function (see the *Transcendental Functions* subsection below). **c(x)** : Returns the cosine of **x**, which is assumed to be in radians. This is a transcendental function (see the *Transcendental Functions* subsection below). **a(x)** : Returns the arctangent of **x**, in radians. This is a transcendental function (see the *Transcendental Functions* subsection below). **l(x)** : Returns the natural logarithm of **x**. This is a transcendental function (see the *Transcendental Functions* subsection below). **e(x)** : Returns the mathematical constant **e** raised to the power of **x**. This is a transcendental function (see the *Transcendental Functions* subsection below). **j(x, n)** : Returns the bessel integer order **n** (truncated) of **x**. This is a transcendental function (see the *Transcendental Functions* subsection below). ## Extended Library The extended library is *not* loaded when the **-s**/**-\-standard** or **-w**/**-\-warn** options are given since they are not part of the library defined by the [standard][1]. The extended library is a **non-portable extension**. **p(x, y)** : Calculates **x** to the power of **y**, even if **y** is not an integer, and returns the result to the current **scale**. It is an error if **y** is negative and **x** is **0**. This is a transcendental function (see the *Transcendental Functions* subsection below). **r(x, p)** : Returns **x** rounded to **p** decimal places according to the rounding mode [round half away from **0**][3]. **ceil(x, p)** : Returns **x** rounded to **p** decimal places according to the rounding mode [round away from **0**][6]. **f(x)** : Returns the factorial of the truncated absolute value of **x**. **perm(n, k)** : Returns the permutation of the truncated absolute value of **n** of the truncated absolute value of **k**, if **k \<= n**. If not, it returns **0**. **comb(n, k)** : Returns the combination of the truncated absolute value of **n** of the truncated absolute value of **k**, if **k \<= n**. If not, it returns **0**. **l2(x)** : Returns the logarithm base **2** of **x**. This is a transcendental function (see the *Transcendental Functions* subsection below). **l10(x)** : Returns the logarithm base **10** of **x**. This is a transcendental function (see the *Transcendental Functions* subsection below). **log(x, b)** : Returns the logarithm base **b** of **x**. This is a transcendental function (see the *Transcendental Functions* subsection below). **cbrt(x)** : Returns the cube root of **x**. **root(x, n)** : Calculates the truncated value of **n**, **r**, and returns the **r**th root of **x** to the current **scale**. If **r** is **0** or negative, this raises an error and causes bc(1) to reset (see the **RESET** section). It also raises an error and causes bc(1) to reset if **r** is even and **x** is negative. **gcd(a, b)** : Returns the greatest common divisor (factor) of the truncated absolute value of **a** and the truncated absolute value of **b**. **lcm(a, b)** : Returns the least common multiple of the truncated absolute value of **a** and the truncated absolute value of **b**. **pi(p)** : Returns **pi** to **p** decimal places. This is a transcendental function (see the *Transcendental Functions* subsection below). **t(x)** : Returns the tangent of **x**, which is assumed to be in radians. This is a transcendental function (see the *Transcendental Functions* subsection below). **a2(y, x)** : Returns the arctangent of **y/x**, in radians. If both **y** and **x** are equal to **0**, it raises an error and causes bc(1) to reset (see the **RESET** section). Otherwise, if **x** is greater than **0**, it returns **a(y/x)**. If **x** is less than **0**, and **y** is greater than or equal to **0**, it returns **a(y/x)+pi**. If **x** is less than **0**, and **y** is less than **0**, it returns **a(y/x)-pi**. If **x** is equal to **0**, and **y** is greater than **0**, it returns **pi/2**. If **x** is equal to **0**, and **y** is less than **0**, it returns **-pi/2**. This function is the same as the **atan2()** function in many programming languages. This is a transcendental function (see the *Transcendental Functions* subsection below). **sin(x)** : Returns the sine of **x**, which is assumed to be in radians. This is an alias of **s(x)**. This is a transcendental function (see the *Transcendental Functions* subsection below). **cos(x)** : Returns the cosine of **x**, which is assumed to be in radians. This is an alias of **c(x)**. This is a transcendental function (see the *Transcendental Functions* subsection below). **tan(x)** : Returns the tangent of **x**, which is assumed to be in radians. If **x** is equal to **1** or **-1**, this raises an error and causes bc(1) to reset (see the **RESET** section). This is an alias of **t(x)**. This is a transcendental function (see the *Transcendental Functions* subsection below). **atan(x)** : Returns the arctangent of **x**, in radians. This is an alias of **a(x)**. This is a transcendental function (see the *Transcendental Functions* subsection below). **atan2(y, x)** : Returns the arctangent of **y/x**, in radians. If both **y** and **x** are equal to **0**, it raises an error and causes bc(1) to reset (see the **RESET** section). Otherwise, if **x** is greater than **0**, it returns **a(y/x)**. If **x** is less than **0**, and **y** is greater than or equal to **0**, it returns **a(y/x)+pi**. If **x** is less than **0**, and **y** is less than **0**, it returns **a(y/x)-pi**. If **x** is equal to **0**, and **y** is greater than **0**, it returns **pi/2**. If **x** is equal to **0**, and **y** is less than **0**, it returns **-pi/2**. This function is the same as the **atan2()** function in many programming languages. This is an alias of **a2(y, x)**. This is a transcendental function (see the *Transcendental Functions* subsection below). **r2d(x)** : Converts **x** from radians to degrees and returns the result. This is a transcendental function (see the *Transcendental Functions* subsection below). **d2r(x)** : Converts **x** from degrees to radians and returns the result. This is a transcendental function (see the *Transcendental Functions* subsection below). **frand(p)** : Generates a pseudo-random number between **0** (inclusive) and **1** (exclusive) with the number of decimal digits after the decimal point equal to the truncated absolute value of **p**. If **p** is not **0**, then calling this function will change the value of **seed**. If **p** is **0**, then **0** is returned, and **seed** is *not* changed. **ifrand(i, p)** : Generates a pseudo-random number that is between **0** (inclusive) and the truncated absolute value of **i** (exclusive) with the number of decimal digits after the decimal point equal to the truncated absolute value of **p**. If the absolute value of **i** is greater than or equal to **2**, and **p** is not **0**, then calling this function will change the value of **seed**; otherwise, **0** is returned and **seed** is not changed. **srand(x)** : Returns **x** with its sign flipped with probability **0.5**. In other words, it randomizes the sign of **x**. **brand()** : Returns a random boolean value (either **0** or **1**). **band(a, b)** : Takes the truncated absolute value of both **a** and **b** and calculates and returns the result of the bitwise **and** operation between them. If you want to use signed two's complement arguments, use **s2u(x)** to convert. **bor(a, b)** : Takes the truncated absolute value of both **a** and **b** and calculates and returns the result of the bitwise **or** operation between them. If you want to use signed two's complement arguments, use **s2u(x)** to convert. **bxor(a, b)** : Takes the truncated absolute value of both **a** and **b** and calculates and returns the result of the bitwise **xor** operation between them. If you want to use signed two's complement arguments, use **s2u(x)** to convert. **bshl(a, b)** : Takes the truncated absolute value of both **a** and **b** and calculates and returns the result of **a** bit-shifted left by **b** places. If you want to use signed two's complement arguments, use **s2u(x)** to convert. **bshr(a, b)** : Takes the truncated absolute value of both **a** and **b** and calculates and returns the truncated result of **a** bit-shifted right by **b** places. If you want to use signed two's complement arguments, use **s2u(x)** to convert. **bnotn(x, n)** : Takes the truncated absolute value of **x** and does a bitwise not as though it has the same number of bytes as the truncated absolute value of **n**. If you want to a use signed two's complement argument, use **s2u(x)** to convert. **bnot8(x)** : Does a bitwise not of the truncated absolute value of **x** as though it has **8** binary digits (1 unsigned byte). If you want to a use signed two's complement argument, use **s2u(x)** to convert. **bnot16(x)** : Does a bitwise not of the truncated absolute value of **x** as though it has **16** binary digits (2 unsigned bytes). If you want to a use signed two's complement argument, use **s2u(x)** to convert. **bnot32(x)** : Does a bitwise not of the truncated absolute value of **x** as though it has **32** binary digits (4 unsigned bytes). If you want to a use signed two's complement argument, use **s2u(x)** to convert. **bnot64(x)** : Does a bitwise not of the truncated absolute value of **x** as though it has **64** binary digits (8 unsigned bytes). If you want to a use signed two's complement argument, use **s2u(x)** to convert. **bnot(x)** : Does a bitwise not of the truncated absolute value of **x** as though it has the minimum number of power of two unsigned bytes. If you want to a use signed two's complement argument, use **s2u(x)** to convert. **brevn(x, n)** : Runs a bit reversal on the truncated absolute value of **x** as though it has the same number of 8-bit bytes as the truncated absolute value of **n**. If you want to a use signed two's complement argument, use **s2u(x)** to convert. **brev8(x)** : Runs a bit reversal on the truncated absolute value of **x** as though it has 8 binary digits (1 unsigned byte). If you want to a use signed two's complement argument, use **s2u(x)** to convert. **brev16(x)** : Runs a bit reversal on the truncated absolute value of **x** as though it has 16 binary digits (2 unsigned bytes). If you want to a use signed two's complement argument, use **s2u(x)** to convert. **brev32(x)** : Runs a bit reversal on the truncated absolute value of **x** as though it has 32 binary digits (4 unsigned bytes). If you want to a use signed two's complement argument, use **s2u(x)** to convert. **brev64(x)** : Runs a bit reversal on the truncated absolute value of **x** as though it has 64 binary digits (8 unsigned bytes). If you want to a use signed two's complement argument, use **s2u(x)** to convert. **brev(x)** : Runs a bit reversal on the truncated absolute value of **x** as though it has the minimum number of power of two unsigned bytes. If you want to a use signed two's complement argument, use **s2u(x)** to convert. **broln(x, p, n)** : Does a left bitwise rotatation of the truncated absolute value of **x**, as though it has the same number of unsigned 8-bit bytes as the truncated absolute value of **n**, by the number of places equal to the truncated absolute value of **p** modded by the **2** to the power of the number of binary digits in **n** 8-bit bytes. If you want to a use signed two's complement argument, use **s2u(x)** to convert. **brol8(x, p)** : Does a left bitwise rotatation of the truncated absolute value of **x**, as though it has **8** binary digits (**1** unsigned byte), by the number of places equal to the truncated absolute value of **p** modded by **2** to the power of **8**. If you want to a use signed two's complement argument, use **s2u(x)** to convert. **brol16(x, p)** : Does a left bitwise rotatation of the truncated absolute value of **x**, as though it has **16** binary digits (**2** unsigned bytes), by the number of places equal to the truncated absolute value of **p** modded by **2** to the power of **16**. If you want to a use signed two's complement argument, use **s2u(x)** to convert. **brol32(x, p)** : Does a left bitwise rotatation of the truncated absolute value of **x**, as though it has **32** binary digits (**2** unsigned bytes), by the number of places equal to the truncated absolute value of **p** modded by **2** to the power of **32**. If you want to a use signed two's complement argument, use **s2u(x)** to convert. **brol64(x, p)** : Does a left bitwise rotatation of the truncated absolute value of **x**, as though it has **64** binary digits (**2** unsigned bytes), by the number of places equal to the truncated absolute value of **p** modded by **2** to the power of **64**. If you want to a use signed two's complement argument, use **s2u(x)** to convert. **brol(x, p)** : Does a left bitwise rotatation of the truncated absolute value of **x**, as though it has the minimum number of power of two unsigned 8-bit bytes, by the number of places equal to the truncated absolute value of **p** modded by 2 to the power of the number of binary digits in the minimum number of 8-bit bytes. If you want to a use signed two's complement argument, use **s2u(x)** to convert. **brorn(x, p, n)** : Does a right bitwise rotatation of the truncated absolute value of **x**, as though it has the same number of unsigned 8-bit bytes as the truncated absolute value of **n**, by the number of places equal to the truncated absolute value of **p** modded by the **2** to the power of the number of binary digits in **n** 8-bit bytes. If you want to a use signed two's complement argument, use **s2u(x)** to convert. **bror8(x, p)** : Does a right bitwise rotatation of the truncated absolute value of **x**, as though it has **8** binary digits (**1** unsigned byte), by the number of places equal to the truncated absolute value of **p** modded by **2** to the power of **8**. If you want to a use signed two's complement argument, use **s2u(x)** to convert. **bror16(x, p)** : Does a right bitwise rotatation of the truncated absolute value of **x**, as though it has **16** binary digits (**2** unsigned bytes), by the number of places equal to the truncated absolute value of **p** modded by **2** to the power of **16**. If you want to a use signed two's complement argument, use **s2u(x)** to convert. **bror32(x, p)** : Does a right bitwise rotatation of the truncated absolute value of **x**, as though it has **32** binary digits (**2** unsigned bytes), by the number of places equal to the truncated absolute value of **p** modded by **2** to the power of **32**. If you want to a use signed two's complement argument, use **s2u(x)** to convert. **bror64(x, p)** : Does a right bitwise rotatation of the truncated absolute value of **x**, as though it has **64** binary digits (**2** unsigned bytes), by the number of places equal to the truncated absolute value of **p** modded by **2** to the power of **64**. If you want to a use signed two's complement argument, use **s2u(x)** to convert. **bror(x, p)** : Does a right bitwise rotatation of the truncated absolute value of **x**, as though it has the minimum number of power of two unsigned 8-bit bytes, by the number of places equal to the truncated absolute value of **p** modded by 2 to the power of the number of binary digits in the minimum number of 8-bit bytes. If you want to a use signed two's complement argument, use **s2u(x)** to convert. **bmodn(x, n)** : Returns the modulus of the truncated absolute value of **x** by **2** to the power of the multiplication of the truncated absolute value of **n** and **8**. If you want to a use signed two's complement argument, use **s2u(x)** to convert. **bmod8(x, n)** : Returns the modulus of the truncated absolute value of **x** by **2** to the power of **8**. If you want to a use signed two's complement argument, use **s2u(x)** to convert. **bmod16(x, n)** : Returns the modulus of the truncated absolute value of **x** by **2** to the power of **16**. If you want to a use signed two's complement argument, use **s2u(x)** to convert. **bmod32(x, n)** : Returns the modulus of the truncated absolute value of **x** by **2** to the power of **32**. If you want to a use signed two's complement argument, use **s2u(x)** to convert. **bmod64(x, n)** : Returns the modulus of the truncated absolute value of **x** by **2** to the power of **64**. If you want to a use signed two's complement argument, use **s2u(x)** to convert. **bunrev(t)** : Assumes **t** is a bitwise-reversed number with an extra set bit one place more significant than the real most significant bit (which was the least significant bit in the original number). This number is reversed and returned without the extra set bit. This function is used to implement other bitwise functions; it is not meant to be used by users, but it can be. **plz(x)** : If **x** is not equal to **0** and greater that **-1** and less than **1**, it is printed with a leading zero, regardless of the use of the **-z** option (see the **OPTIONS** section) and without a trailing newline. Otherwise, **x** is printed normally, without a trailing newline. **plznl(x)** : If **x** is not equal to **0** and greater that **-1** and less than **1**, it is printed with a leading zero, regardless of the use of the **-z** option (see the **OPTIONS** section) and with a trailing newline. Otherwise, **x** is printed normally, with a trailing newline. **pnlz(x)** : If **x** is not equal to **0** and greater that **-1** and less than **1**, it is printed without a leading zero, regardless of the use of the **-z** option (see the **OPTIONS** section) and without a trailing newline. Otherwise, **x** is printed normally, without a trailing newline. **pnlznl(x)** : If **x** is not equal to **0** and greater that **-1** and less than **1**, it is printed without a leading zero, regardless of the use of the **-z** option (see the **OPTIONS** section) and with a trailing newline. Otherwise, **x** is printed normally, with a trailing newline. **ubytes(x)** : Returns the numbers of unsigned integer bytes required to hold the truncated absolute value of **x**. **sbytes(x)** : Returns the numbers of signed, two's-complement integer bytes required to hold the truncated value of **x**. **s2u(x)** : Returns **x** if it is non-negative. If it *is* negative, then it calculates what **x** would be as a 2's-complement signed integer and returns the non-negative integer that would have the same representation in binary. **s2un(x,n)** : Returns **x** if it is non-negative. If it *is* negative, then it calculates what **x** would be as a 2's-complement signed integer with **n** bytes and returns the non-negative integer that would have the same representation in binary. If **x** cannot fit into **n** 2's-complement signed bytes, it is truncated to fit. **hex(x)** : Outputs the hexadecimal (base **16**) representation of **x**. This is a **void** function (see the *Void Functions* subsection of the **FUNCTIONS** section). **binary(x)** : Outputs the binary (base **2**) representation of **x**. This is a **void** function (see the *Void Functions* subsection of the **FUNCTIONS** section). **output(x, b)** : Outputs the base **b** representation of **x**. This is a **void** function (see the *Void Functions* subsection of the **FUNCTIONS** section). **uint(x)** : Outputs the representation, in binary and hexadecimal, of **x** as an unsigned integer in as few power of two bytes as possible. Both outputs are split into bytes separated by spaces. If **x** is not an integer or is negative, an error message is printed instead, but bc(1) is not reset (see the **RESET** section). This is a **void** function (see the *Void Functions* subsection of the **FUNCTIONS** section). **int(x)** : Outputs the representation, in binary and hexadecimal, of **x** as a signed, two's-complement integer in as few power of two bytes as possible. Both outputs are split into bytes separated by spaces. If **x** is not an integer, an error message is printed instead, but bc(1) is not reset (see the **RESET** section). This is a **void** function (see the *Void Functions* subsection of the **FUNCTIONS** section). **uintn(x, n)** : Outputs the representation, in binary and hexadecimal, of **x** as an unsigned integer in **n** bytes. Both outputs are split into bytes separated by spaces. If **x** is not an integer, is negative, or cannot fit into **n** bytes, an error message is printed instead, but bc(1) is not reset (see the **RESET** section). This is a **void** function (see the *Void Functions* subsection of the **FUNCTIONS** section). **intn(x, n)** : Outputs the representation, in binary and hexadecimal, of **x** as a signed, two's-complement integer in **n** bytes. Both outputs are split into bytes separated by spaces. If **x** is not an integer or cannot fit into **n** bytes, an error message is printed instead, but bc(1) is not reset (see the **RESET** section). This is a **void** function (see the *Void Functions* subsection of the **FUNCTIONS** section). **uint8(x)** : Outputs the representation, in binary and hexadecimal, of **x** as an unsigned integer in **1** byte. Both outputs are split into bytes separated by spaces. If **x** is not an integer, is negative, or cannot fit into **1** byte, an error message is printed instead, but bc(1) is not reset (see the **RESET** section). This is a **void** function (see the *Void Functions* subsection of the **FUNCTIONS** section). **int8(x)** : Outputs the representation, in binary and hexadecimal, of **x** as a signed, two's-complement integer in **1** byte. Both outputs are split into bytes separated by spaces. If **x** is not an integer or cannot fit into **1** byte, an error message is printed instead, but bc(1) is not reset (see the **RESET** section). This is a **void** function (see the *Void Functions* subsection of the **FUNCTIONS** section). **uint16(x)** : Outputs the representation, in binary and hexadecimal, of **x** as an unsigned integer in **2** bytes. Both outputs are split into bytes separated by spaces. If **x** is not an integer, is negative, or cannot fit into **2** bytes, an error message is printed instead, but bc(1) is not reset (see the **RESET** section). This is a **void** function (see the *Void Functions* subsection of the **FUNCTIONS** section). **int16(x)** : Outputs the representation, in binary and hexadecimal, of **x** as a signed, two's-complement integer in **2** bytes. Both outputs are split into bytes separated by spaces. If **x** is not an integer or cannot fit into **2** bytes, an error message is printed instead, but bc(1) is not reset (see the **RESET** section). This is a **void** function (see the *Void Functions* subsection of the **FUNCTIONS** section). **uint32(x)** : Outputs the representation, in binary and hexadecimal, of **x** as an unsigned integer in **4** bytes. Both outputs are split into bytes separated by spaces. If **x** is not an integer, is negative, or cannot fit into **4** bytes, an error message is printed instead, but bc(1) is not reset (see the **RESET** section). This is a **void** function (see the *Void Functions* subsection of the **FUNCTIONS** section). **int32(x)** : Outputs the representation, in binary and hexadecimal, of **x** as a signed, two's-complement integer in **4** bytes. Both outputs are split into bytes separated by spaces. If **x** is not an integer or cannot fit into **4** bytes, an error message is printed instead, but bc(1) is not reset (see the **RESET** section). This is a **void** function (see the *Void Functions* subsection of the **FUNCTIONS** section). **uint64(x)** : Outputs the representation, in binary and hexadecimal, of **x** as an unsigned integer in **8** bytes. Both outputs are split into bytes separated by spaces. If **x** is not an integer, is negative, or cannot fit into **8** bytes, an error message is printed instead, but bc(1) is not reset (see the **RESET** section). This is a **void** function (see the *Void Functions* subsection of the **FUNCTIONS** section). **int64(x)** : Outputs the representation, in binary and hexadecimal, of **x** as a signed, two's-complement integer in **8** bytes. Both outputs are split into bytes separated by spaces. If **x** is not an integer or cannot fit into **8** bytes, an error message is printed instead, but bc(1) is not reset (see the **RESET** section). This is a **void** function (see the *Void Functions* subsection of the **FUNCTIONS** section). **hex_uint(x, n)** : Outputs the representation of the truncated absolute value of **x** as an unsigned integer in hexadecimal using **n** bytes. Not all of the value will be output if **n** is too small. This is a **void** function (see the *Void Functions* subsection of the **FUNCTIONS** section). **binary_uint(x, n)** : Outputs the representation of the truncated absolute value of **x** as an unsigned integer in binary using **n** bytes. Not all of the value will be output if **n** is too small. This is a **void** function (see the *Void Functions* subsection of the **FUNCTIONS** section). **output_uint(x, n)** : Outputs the representation of the truncated absolute value of **x** as an unsigned integer in the current **obase** (see the **SYNTAX** section) using **n** bytes. Not all of the value will be output if **n** is too small. This is a **void** function (see the *Void Functions* subsection of the **FUNCTIONS** section). **output_byte(x, i)** : Outputs byte **i** of the truncated absolute value of **x**, where **0** is the least significant byte and **number_of_bytes - 1** is the most significant byte. This is a **void** function (see the *Void Functions* subsection of the **FUNCTIONS** section). ## Transcendental Functions All transcendental functions can return slightly inaccurate results (up to 1 [ULP][4]). This is unavoidable, and [this article][5] explains why it is impossible and unnecessary to calculate exact results for the transcendental functions. Because of the possible inaccuracy, I recommend that users call those functions with the precision (**scale**) set to at least 1 higher than is necessary. If exact results are *absolutely* required, users can double the precision (**scale**) and then truncate. The transcendental functions in the standard math library are: * **s(x)** * **c(x)** * **a(x)** * **l(x)** * **e(x)** * **j(x, n)** The transcendental functions in the extended math library are: * **l2(x)** * **l10(x)** * **log(x, b)** * **pi(p)** * **t(x)** * **a2(y, x)** * **sin(x)** * **cos(x)** * **tan(x)** * **atan(x)** * **atan2(y, x)** * **r2d(x)** * **d2r(x)** # RESET When bc(1) encounters an error or a signal that it has a non-default handler for, it resets. This means that several things happen. First, any functions that are executing are stopped and popped off the stack. The behavior is not unlike that of exceptions in programming languages. Then the execution point is set so that any code waiting to execute (after all functions returned) is skipped. Thus, when bc(1) resets, it skips any remaining code waiting to be executed. Then, if it is interactive mode, and the error was not a fatal error (see the **EXIT STATUS** section), it asks for more input; otherwise, it exits with the appropriate return code. Note that this reset behavior is different from the GNU bc(1), which attempts to start executing the statement right after the one that caused an error. # PERFORMANCE Most bc(1) implementations use **char** types to calculate the value of **1** decimal digit at a time, but that can be slow. This bc(1) does something different. It uses large integers to calculate more than **1** decimal digit at a time. If built in a environment where **BC_LONG_BIT** (see the **LIMITS** section) is **64**, then each integer has **9** decimal digits. If built in an environment where **BC_LONG_BIT** is **32** then each integer has **4** decimal digits. This value (the number of decimal digits per large integer) is called **BC_BASE_DIGS**. The actual values of **BC_LONG_BIT** and **BC_BASE_DIGS** can be queried with the **limits** statement. In addition, this bc(1) uses an even larger integer for overflow checking. This integer type depends on the value of **BC_LONG_BIT**, but is always at least twice as large as the integer type used to store digits. # LIMITS The following are the limits on bc(1): **BC_LONG_BIT** : The number of bits in the **long** type in the environment where bc(1) was built. This determines how many decimal digits can be stored in a single large integer (see the **PERFORMANCE** section). **BC_BASE_DIGS** : The number of decimal digits per large integer (see the **PERFORMANCE** section). Depends on **BC_LONG_BIT**. **BC_BASE_POW** : The max decimal number that each large integer can store (see **BC_BASE_DIGS**) plus **1**. Depends on **BC_BASE_DIGS**. **BC_OVERFLOW_MAX** : The max number that the overflow type (see the **PERFORMANCE** section) can hold. Depends on **BC_LONG_BIT**. **BC_BASE_MAX** : The maximum output base. Set at **BC_BASE_POW**. **BC_DIM_MAX** : The maximum size of arrays. Set at **SIZE_MAX-1**. **BC_SCALE_MAX** : The maximum **scale**. Set at **BC_OVERFLOW_MAX-1**. **BC_STRING_MAX** : The maximum length of strings. Set at **BC_OVERFLOW_MAX-1**. **BC_NAME_MAX** : The maximum length of identifiers. Set at **BC_OVERFLOW_MAX-1**. **BC_NUM_MAX** : The maximum length of a number (in decimal digits), which includes digits after the decimal point. Set at **BC_OVERFLOW_MAX-1**. **BC_RAND_MAX** : The maximum integer (inclusive) returned by the **rand()** operand. Set at **2\^BC_LONG_BIT-1**. Exponent : The maximum allowable exponent (positive or negative). Set at **BC_OVERFLOW_MAX**. Number of vars : The maximum number of vars/arrays. Set at **SIZE_MAX-1**. The actual values can be queried with the **limits** statement. These limits are meant to be effectively non-existent; the limits are so large (at least on 64-bit machines) that there should not be any point at which they become a problem. In fact, memory should be exhausted before these limits should be hit. # ENVIRONMENT VARIABLES bc(1) recognizes the following environment variables: **POSIXLY_CORRECT** : If this variable exists (no matter the contents), bc(1) behaves as if the **-s** option was given. **BC_ENV_ARGS** : This is another way to give command-line arguments to bc(1). They should be in the same format as all other command-line arguments. These are always processed first, so any files given in **BC_ENV_ARGS** will be processed before arguments and files given on the command-line. This gives the user the ability to set up "standard" options and files to be used at every invocation. The most useful thing for such files to contain would be useful functions that the user might want every time bc(1) runs. The code that parses **BC_ENV_ARGS** will correctly handle quoted arguments, but it does not understand escape sequences. For example, the string **"/home/gavin/some bc file.bc"** will be correctly parsed, but the string **"/home/gavin/some \"bc\" file.bc"** will include the backslashes. The quote parsing will handle either kind of quotes, **'** or **"**. Thus, if you have a file with any number of single quotes in the name, you can use double quotes as the outside quotes, as in **"some 'bc' file.bc"**, and vice versa if you have a file with double quotes. However, handling a file with both kinds of quotes in **BC_ENV_ARGS** is not supported due to the complexity of the parsing, though such files are still supported on the command-line where the parsing is done by the shell. **BC_LINE_LENGTH** : If this environment variable exists and contains an integer that is greater than **1** and is less than **UINT16_MAX** (**2\^16-1**), bc(1) will output lines to that length, including the backslash (**\\**). The default line length is **70**. The special value of **0** will disable line length checking and print numbers without regard to line length and without backslashes and newlines. **BC_BANNER** : If this environment variable exists and contains an integer, then a non-zero value activates the copyright banner when bc(1) is in interactive mode, while zero deactivates it. If bc(1) is not in interactive mode (see the **INTERACTIVE MODE** section), then this environment variable has no effect because bc(1) does not print the banner when not in interactive mode. This environment variable overrides the default, which can be queried with the **-h** or **-\-help** options. **BC_SIGINT_RESET** : If bc(1) is not in interactive mode (see the **INTERACTIVE MODE** section), then this environment variable has no effect because bc(1) exits on **SIGINT** when not in interactive mode. However, when bc(1) is in interactive mode, then if this environment variable exists and contains an integer, a non-zero value makes bc(1) reset on **SIGINT**, rather than exit, and zero makes bc(1) exit. If this environment variable exists and is *not* an integer, then bc(1) will exit on **SIGINT**. This environment variable overrides the default, which can be queried with the **-h** or **-\-help** options. **BC_TTY_MODE** : If TTY mode is *not* available (see the **TTY MODE** section), then this environment variable has no effect. However, when TTY mode is available, then if this environment variable exists and contains an integer, then a non-zero value makes bc(1) use TTY mode, and zero makes bc(1) not use TTY mode. This environment variable overrides the default, which can be queried with the **-h** or **-\-help** options. **BC_PROMPT** : If TTY mode is *not* available (see the **TTY MODE** section), then this environment variable has no effect. However, when TTY mode is available, then if this environment variable exists and contains an integer, a non-zero value makes bc(1) use a prompt, and zero or a non-integer makes bc(1) not use a prompt. If this environment variable does not exist and **BC_TTY_MODE** does, then the value of the **BC_TTY_MODE** environment variable is used. This environment variable and the **BC_TTY_MODE** environment variable override the default, which can be queried with the **-h** or **-\-help** options. +**BC_EXPR_EXIT** + +: If any expressions or expression files are given on the command-line with + **-e**, **-\-expression**, **-f**, or **-\-file**, then if this environment + variable exists and contains an integer, a non-zero value makes bc(1) exit + after executing the expressions and expression files, and a non-zero value + makes bc(1) not exit. + + This environment variable overrides the default, which can be queried with + the **-h** or **-\-help** options. + # EXIT STATUS bc(1) returns the following exit statuses: **0** : No error. **1** : A math error occurred. This follows standard practice of using **1** for expected errors, since math errors will happen in the process of normal execution. Math errors include divide by **0**, taking the square root of a negative number, using a negative number as a bound for the pseudo-random number generator, attempting to convert a negative number to a hardware integer, overflow when converting a number to a hardware integer, overflow when calculating the size of a number, and attempting to use a non-integer where an integer is required. Converting to a hardware integer happens for the second operand of the power (**\^**), places (**\@**), left shift (**\<\<**), and right shift (**\>\>**) operators and their corresponding assignment operators. **2** : A parse error occurred. Parse errors include unexpected **EOF**, using an invalid character, failing to find the end of a string or comment, using a token where it is invalid, giving an invalid expression, giving an invalid print statement, giving an invalid function definition, attempting to assign to an expression that is not a named expression (see the *Named Expressions* subsection of the **SYNTAX** section), giving an invalid **auto** list, having a duplicate **auto**/function parameter, failing to find the end of a code block, attempting to return a value from a **void** function, attempting to use a variable as a reference, and using any extensions when the option **-s** or any equivalents were given. **3** : A runtime error occurred. Runtime errors include assigning an invalid number to any global (**ibase**, **obase**, or **scale**), giving a bad expression to a **read()** call, calling **read()** inside of a **read()** call, type errors, passing the wrong number of arguments to functions, attempting to call an undefined function, and attempting to use a **void** function call as a value in an expression. **4** : A fatal error occurred. Fatal errors include memory allocation errors, I/O errors, failing to open files, attempting to use files that do not have only ASCII characters (bc(1) only accepts ASCII characters), attempting to open a directory as a file, and giving invalid command-line options. The exit status **4** is special; when a fatal error occurs, bc(1) always exits and returns **4**, no matter what mode bc(1) is in. The other statuses will only be returned when bc(1) is not in interactive mode (see the **INTERACTIVE MODE** section), since bc(1) resets its state (see the **RESET** section) and accepts more input when one of those errors occurs in interactive mode. This is also the case when interactive mode is forced by the **-i** flag or **-\-interactive** option. These exit statuses allow bc(1) to be used in shell scripting with error checking, and its normal behavior can be forced by using the **-i** flag or **-\-interactive** option. # INTERACTIVE MODE Per the [standard][1], bc(1) has an interactive mode and a non-interactive mode. Interactive mode is turned on automatically when both **stdin** and **stdout** are hooked to a terminal, but the **-i** flag and **-\-interactive** option can turn it on in other situations. In interactive mode, bc(1) attempts to recover from errors (see the **RESET** section), and in normal execution, flushes **stdout** as soon as execution is done for the current input. bc(1) may also reset on **SIGINT** instead of exit, depending on the contents of, or default for, the **BC_SIGINT_RESET** environment variable (see the **ENVIRONMENT VARIABLES** section). # TTY MODE If **stdin**, **stdout**, and **stderr** are all connected to a TTY, then "TTY mode" is considered to be available, and thus, bc(1) can turn on TTY mode, subject to some settings. If there is the environment variable **BC_TTY_MODE** in the environment (see the **ENVIRONMENT VARIABLES** section), then if that environment variable contains a non-zero integer, bc(1) will turn on TTY mode when **stdin**, **stdout**, and **stderr** are all connected to a TTY. If the **BC_TTY_MODE** environment variable exists but is *not* a non-zero integer, then bc(1) will not turn TTY mode on. If the environment variable **BC_TTY_MODE** does *not* exist, the default setting is used. The default setting can be queried with the **-h** or **-\-help** options. TTY mode is different from interactive mode because interactive mode is required in the [bc(1) specification][1], and interactive mode requires only **stdin** and **stdout** to be connected to a terminal. ## Prompt If TTY mode is available, then a prompt can be enabled. Like TTY mode itself, it can be turned on or off with an environment variable: **BC_PROMPT** (see the **ENVIRONMENT VARIABLES** section). If the environment variable **BC_PROMPT** exists and is a non-zero integer, then the prompt is turned on when **stdin**, **stdout**, and **stderr** are connected to a TTY and the **-P** and **-\-no-prompt** options were not used. The read prompt will be turned on under the same conditions, except that the **-R** and **-\-no-read-prompt** options must also not be used. However, if **BC_PROMPT** does not exist, the prompt can be enabled or disabled with the **BC_TTY_MODE** environment variable, the **-P** and **-\-no-prompt** options, and the **-R** and **-\-no-read-prompt** options. See the **ENVIRONMENT VARIABLES** and **OPTIONS** sections for more details. # SIGNAL HANDLING Sending a **SIGINT** will cause bc(1) to do one of two things. If bc(1) is not in interactive mode (see the **INTERACTIVE MODE** section), or the **BC_SIGINT_RESET** environment variable (see the **ENVIRONMENT VARIABLES** section), or its default, is either not an integer or it is zero, bc(1) will exit. However, if bc(1) is in interactive mode, and the **BC_SIGINT_RESET** or its default is an integer and non-zero, then bc(1) will stop executing the current input and reset (see the **RESET** section) upon receiving a **SIGINT**. Note that "current input" can mean one of two things. If bc(1) is processing input from **stdin** in interactive mode, it will ask for more input. If bc(1) is processing input from a file in interactive mode, it will stop processing the file and start processing the next file, if one exists, or ask for input from **stdin** if no other file exists. This means that if a **SIGINT** is sent to bc(1) as it is executing a file, it can seem as though bc(1) did not respond to the signal since it will immediately start executing the next file. This is by design; most files that users execute when interacting with bc(1) have function definitions, which are quick to parse. If a file takes a long time to execute, there may be a bug in that file. The rest of the files could still be executed without problem, allowing the user to continue. **SIGTERM** and **SIGQUIT** cause bc(1) to clean up and exit, and it uses the default handler for all other signals. # SEE ALSO dc(1) # STANDARDS bc(1) is compliant with the [IEEE Std 1003.1-2017 (“POSIX.1-2017”)][1] specification. The flags **-efghiqsvVw**, all long options, and the extensions noted above are extensions to that specification. Note that the specification explicitly says that bc(1) only accepts numbers that use a period (**.**) as a radix point, regardless of the value of **LC_NUMERIC**. # BUGS None are known. Report bugs at https://git.yzena.com/gavin/bc. # AUTHORS Gavin D. Howard and contributors. [1]: https://pubs.opengroup.org/onlinepubs/9699919799/utilities/bc.html [2]: https://www.gnu.org/software/bc/ [3]: https://en.wikipedia.org/wiki/Rounding#Round_half_away_from_zero [4]: https://en.wikipedia.org/wiki/Unit_in_the_last_place [5]: https://people.eecs.berkeley.edu/~wkahan/LOG10HAF.TXT [6]: https://en.wikipedia.org/wiki/Rounding#Rounding_away_from_zero diff --git a/contrib/bc/manuals/bc/N.1 b/contrib/bc/manuals/bc/N.1 index 56fca3d02b4d..40dbad9bb2f2 100644 --- a/contrib/bc/manuals/bc/N.1 +++ b/contrib/bc/manuals/bc/N.1 @@ -1,2777 +1,2790 @@ .\" .\" SPDX-License-Identifier: BSD-2-Clause .\" .\" Copyright (c) 2018-2021 Gavin D. Howard and contributors. .\" .\" Redistribution and use in source and binary forms, with or without .\" modification, are permitted provided that the following conditions are met: .\" .\" * Redistributions of source code must retain the above copyright notice, .\" this list of conditions and the following disclaimer. .\" .\" * Redistributions in binary form must reproduce the above copyright notice, .\" this list of conditions and the following disclaimer in the documentation .\" and/or other materials provided with the distribution. .\" .\" THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" .\" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE .\" IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE .\" ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE .\" LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR .\" CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF .\" SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS .\" INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN .\" CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) .\" ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE .\" POSSIBILITY OF SUCH DAMAGE. .\" .TH "BC" "1" "June 2021" "Gavin D. Howard" "General Commands Manual" .SH NAME .PP bc - arbitrary-precision decimal arithmetic language and calculator .SH SYNOPSIS .PP \f[B]bc\f[R] [\f[B]-ghilPqRsvVw\f[R]] [\f[B]--global-stacks\f[R]] [\f[B]--help\f[R]] [\f[B]--interactive\f[R]] [\f[B]--mathlib\f[R]] [\f[B]--no-prompt\f[R]] [\f[B]--no-read-prompt\f[R]] [\f[B]--quiet\f[R]] [\f[B]--standard\f[R]] [\f[B]--warn\f[R]] [\f[B]--version\f[R]] [\f[B]-e\f[R] \f[I]expr\f[R]] [\f[B]--expression\f[R]=\f[I]expr\f[R]\&...] [\f[B]-f\f[R] \f[I]file\f[R]\&...] [\f[B]--file\f[R]=\f[I]file\f[R]\&...] [\f[I]file\f[R]\&...] .SH DESCRIPTION .PP bc(1) is an interactive processor for a language first standardized in 1991 by POSIX. (The current standard is here (https://pubs.opengroup.org/onlinepubs/9699919799/utilities/bc.html).) The language provides unlimited precision decimal arithmetic and is somewhat C-like, but there are differences. Such differences will be noted in this document. .PP After parsing and handling options, this bc(1) reads any files given on the command line and executes them before reading from \f[B]stdin\f[R]. .PP This bc(1) is a drop-in replacement for \f[I]any\f[R] bc(1), including (and especially) the GNU bc(1). It also has many extensions and extra features beyond other implementations. .PP \f[B]Note\f[R]: If running this bc(1) on \f[I]any\f[R] script meant for another bc(1) gives a parse error, it is probably because a word this bc(1) reserves as a keyword is used as the name of a function, variable, or array. To fix that, use the command-line option \f[B]-r\f[R] \f[I]keyword\f[R], where \f[I]keyword\f[R] is the keyword that is used as a name in the script. For more information, see the \f[B]OPTIONS\f[R] section. .PP If parsing scripts meant for other bc(1) implementations still does not work, that is a bug and should be reported. See the \f[B]BUGS\f[R] section. .SH OPTIONS .PP The following are the options that bc(1) accepts. .TP \f[B]-g\f[R], \f[B]--global-stacks\f[R] Turns the globals \f[B]ibase\f[R], \f[B]obase\f[R], \f[B]scale\f[R], and \f[B]seed\f[R] into stacks. .RS .PP This has the effect that a copy of the current value of all four are pushed onto a stack for every function call, as well as popped when every function returns. This means that functions can assign to any and all of those globals without worrying that the change will affect other functions. Thus, a hypothetical function named \f[B]output(x,b)\f[R] that simply printed \f[B]x\f[R] in base \f[B]b\f[R] could be written like this: .IP .nf \f[C] define void output(x, b) { obase=b x } \f[R] .fi .PP instead of like this: .IP .nf \f[C] define void output(x, b) { auto c c=obase obase=b x obase=c } \f[R] .fi .PP This makes writing functions much easier. .PP (\f[B]Note\f[R]: the function \f[B]output(x,b)\f[R] exists in the extended math library. See the \f[B]LIBRARY\f[R] section.) .PP However, since using this flag means that functions cannot set \f[B]ibase\f[R], \f[B]obase\f[R], \f[B]scale\f[R], or \f[B]seed\f[R] globally, functions that are made to do so cannot work anymore. There are two possible use cases for that, and each has a solution. .PP First, if a function is called on startup to turn bc(1) into a number converter, it is possible to replace that capability with various shell aliases. Examples: .IP .nf \f[C] alias d2o=\[dq]bc -e ibase=A -e obase=8\[dq] alias h2b=\[dq]bc -e ibase=G -e obase=2\[dq] \f[R] .fi .PP Second, if the purpose of a function is to set \f[B]ibase\f[R], \f[B]obase\f[R], \f[B]scale\f[R], or \f[B]seed\f[R] globally for any other purpose, it could be split into one to four functions (based on how many globals it sets) and each of those functions could return the desired value for a global. .PP For functions that set \f[B]seed\f[R], the value assigned to \f[B]seed\f[R] is not propagated to parent functions. This means that the sequence of pseudo-random numbers that they see will not be the same sequence of pseudo-random numbers that any parent sees. This is only the case once \f[B]seed\f[R] has been set. .PP If a function desires to not affect the sequence of pseudo-random numbers of its parents, but wants to use the same \f[B]seed\f[R], it can use the following line: .IP .nf \f[C] seed = seed \f[R] .fi .PP If the behavior of this option is desired for every run of bc(1), then users could make sure to define \f[B]BC_ENV_ARGS\f[R] and include this option (see the \f[B]ENVIRONMENT VARIABLES\f[R] section for more details). .PP If \f[B]-s\f[R], \f[B]-w\f[R], or any equivalents are used, this option is ignored. .PP This is a \f[B]non-portable extension\f[R]. .RE .TP \f[B]-h\f[R], \f[B]--help\f[R] Prints a usage message and quits. .TP \f[B]-i\f[R], \f[B]--interactive\f[R] Forces interactive mode. (See the \f[B]INTERACTIVE MODE\f[R] section.) .RS .PP This is a \f[B]non-portable extension\f[R]. .RE .TP \f[B]-L\f[R], \f[B]--no-line-length\f[R] Disables line length checking and prints numbers without backslashes and newlines. In other words, this option sets \f[B]BC_LINE_LENGTH\f[R] to \f[B]0\f[R] (see the \f[B]ENVIRONMENT VARIABLES\f[R] section). .RS .PP This is a \f[B]non-portable extension\f[R]. .RE .TP \f[B]-l\f[R], \f[B]--mathlib\f[R] Sets \f[B]scale\f[R] (see the \f[B]SYNTAX\f[R] section) to \f[B]20\f[R] and loads the included math library and the extended math library before running any code, including any expressions or files specified on the command line. .RS .PP To learn what is in the libraries, see the \f[B]LIBRARY\f[R] section. .RE .TP \f[B]-P\f[R], \f[B]--no-prompt\f[R] Disables the prompt in TTY mode. (The prompt is only enabled in TTY mode. See the \f[B]TTY MODE\f[R] section.) This is mostly for those users that do not want a prompt or are not used to having them in bc(1). Most of those users would want to put this option in \f[B]BC_ENV_ARGS\f[R] (see the \f[B]ENVIRONMENT VARIABLES\f[R] section). .RS .PP These options override the \f[B]BC_PROMPT\f[R] and \f[B]BC_TTY_MODE\f[R] environment variables (see the \f[B]ENVIRONMENT VARIABLES\f[R] section). .PP This is a \f[B]non-portable extension\f[R]. .RE .TP \f[B]-R\f[R], \f[B]--no-read-prompt\f[R] Disables the read prompt in TTY mode. (The read prompt is only enabled in TTY mode. See the \f[B]TTY MODE\f[R] section.) This is mostly for those users that do not want a read prompt or are not used to having them in bc(1). Most of those users would want to put this option in \f[B]BC_ENV_ARGS\f[R] (see the \f[B]ENVIRONMENT VARIABLES\f[R] section). This option is also useful in hash bang lines of bc(1) scripts that prompt for user input. .RS .PP This option does not disable the regular prompt because the read prompt is only used when the \f[B]read()\f[R] built-in function is called. .PP These options \f[I]do\f[R] override the \f[B]BC_PROMPT\f[R] and \f[B]BC_TTY_MODE\f[R] environment variables (see the \f[B]ENVIRONMENT VARIABLES\f[R] section), but only for the read prompt. .PP This is a \f[B]non-portable extension\f[R]. .RE .TP \f[B]-r\f[R] \f[I]keyword\f[R], \f[B]--redefine\f[R]=\f[I]keyword\f[R] Redefines \f[I]keyword\f[R] in order to allow it to be used as a function, variable, or array name. This is useful when this bc(1) gives parse errors when parsing scripts meant for other bc(1) implementations. .RS .PP The keywords this bc(1) allows to be redefined are: .IP \[bu] 2 \f[B]abs\f[R] .IP \[bu] 2 \f[B]asciify\f[R] .IP \[bu] 2 \f[B]continue\f[R] .IP \[bu] 2 \f[B]divmod\f[R] .IP \[bu] 2 \f[B]else\f[R] .IP \[bu] 2 \f[B]halt\f[R] .IP \[bu] 2 \f[B]irand\f[R] .IP \[bu] 2 \f[B]last\f[R] .IP \[bu] 2 \f[B]limits\f[R] .IP \[bu] 2 \f[B]maxibase\f[R] .IP \[bu] 2 \f[B]maxobase\f[R] .IP \[bu] 2 \f[B]maxrand\f[R] .IP \[bu] 2 \f[B]maxscale\f[R] .IP \[bu] 2 \f[B]modexp\f[R] .IP \[bu] 2 \f[B]print\f[R] .IP \[bu] 2 \f[B]rand\f[R] .IP \[bu] 2 \f[B]read\f[R] .IP \[bu] 2 \f[B]seed\f[R] .IP \[bu] 2 \f[B]stream\f[R] .PP If any of those keywords are used as a function, variable, or array name in a script, use this option with the keyword as the argument. If multiple are used, use this option for all of them; it can be used multiple times. .PP Keywords are \f[I]not\f[R] redefined when parsing the builtin math library (see the \f[B]LIBRARY\f[R] section). .PP It is a fatal error to redefine keywords mandated by the POSIX standard. It is a fatal error to attempt to redefine words that this bc(1) does not reserve as keywords. .RE .TP \f[B]-q\f[R], \f[B]--quiet\f[R] This option is for compatibility with the GNU bc(1) (https://www.gnu.org/software/bc/); it is a no-op. Without this option, GNU bc(1) prints a copyright header. This bc(1) only prints the copyright header if one or more of the \f[B]-v\f[R], \f[B]-V\f[R], or \f[B]--version\f[R] options are given. .RS .PP This is a \f[B]non-portable extension\f[R]. .RE .TP \f[B]-s\f[R], \f[B]--standard\f[R] Process exactly the language defined by the standard (https://pubs.opengroup.org/onlinepubs/9699919799/utilities/bc.html) and error if any extensions are used. .RS .PP This is a \f[B]non-portable extension\f[R]. .RE .TP \f[B]-v\f[R], \f[B]-V\f[R], \f[B]--version\f[R] Print the version information (copyright header) and exit. .RS .PP This is a \f[B]non-portable extension\f[R]. .RE .TP \f[B]-w\f[R], \f[B]--warn\f[R] Like \f[B]-s\f[R] and \f[B]--standard\f[R], except that warnings (and not errors) are printed for non-standard extensions and execution continues normally. .RS .PP This is a \f[B]non-portable extension\f[R]. .RE .TP \f[B]-z\f[R], \f[B]--leading-zeroes\f[R] Makes bc(1) print all numbers greater than \f[B]-1\f[R] and less than \f[B]1\f[R], and not equal to \f[B]0\f[R], with a leading zero. .RS .PP This can be set for individual numbers with the \f[B]plz(x)\f[R], plznl(x)**, \f[B]pnlz(x)\f[R], and \f[B]pnlznl(x)\f[R] functions in the extended math library (see the \f[B]LIBRARY\f[R] section). .PP This is a \f[B]non-portable extension\f[R]. .RE .TP \f[B]-e\f[R] \f[I]expr\f[R], \f[B]--expression\f[R]=\f[I]expr\f[R] Evaluates \f[I]expr\f[R]. If multiple expressions are given, they are evaluated in order. If files are given as well (see below), the expressions and files are evaluated in the order given. This means that if a file is given before an expression, the file is read in and evaluated first. .RS .PP If this option is given on the command-line (i.e., not in \f[B]BC_ENV_ARGS\f[R], see the \f[B]ENVIRONMENT VARIABLES\f[R] section), then after processing all expressions and files, bc(1) will exit, unless \f[B]-\f[R] (\f[B]stdin\f[R]) was given as an argument at least once to \f[B]-f\f[R] or \f[B]--file\f[R], whether on the command-line or in \f[B]BC_ENV_ARGS\f[R]. However, if any other \f[B]-e\f[R], \f[B]--expression\f[R], \f[B]-f\f[R], or \f[B]--file\f[R] arguments are given after \f[B]-f-\f[R] or equivalent is given, bc(1) will give a fatal error and exit. .PP This is a \f[B]non-portable extension\f[R]. .RE .TP \f[B]-f\f[R] \f[I]file\f[R], \f[B]--file\f[R]=\f[I]file\f[R] Reads in \f[I]file\f[R] and evaluates it, line by line, as though it were read through \f[B]stdin\f[R]. If expressions are also given (see above), the expressions are evaluated in the order given. .RS .PP If this option is given on the command-line (i.e., not in \f[B]BC_ENV_ARGS\f[R], see the \f[B]ENVIRONMENT VARIABLES\f[R] section), then after processing all expressions and files, bc(1) will exit, unless \f[B]-\f[R] (\f[B]stdin\f[R]) was given as an argument at least once to \f[B]-f\f[R] or \f[B]--file\f[R]. However, if any other \f[B]-e\f[R], \f[B]--expression\f[R], \f[B]-f\f[R], or \f[B]--file\f[R] arguments are given after \f[B]-f-\f[R] or equivalent is given, bc(1) will give a fatal error and exit. .PP This is a \f[B]non-portable extension\f[R]. .RE .PP All long options are \f[B]non-portable extensions\f[R]. .SH STDIN .PP If no files or expressions are given by the \f[B]-f\f[R], \f[B]--file\f[R], \f[B]-e\f[R], or \f[B]--expression\f[R] options, then bc(1) read from \f[B]stdin\f[R]. .PP However, there are a few caveats to this. .PP First, \f[B]stdin\f[R] is evaluated a line at a time. The only exception to this is if the parse cannot complete. That means that starting a string without ending it or starting a function, \f[B]if\f[R] statement, or loop without ending it will also cause bc(1) to not execute. .PP Second, after an \f[B]if\f[R] statement, bc(1) doesn\[cq]t know if an \f[B]else\f[R] statement will follow, so it will not execute until it knows there will not be an \f[B]else\f[R] statement. .SH STDOUT .PP Any non-error output is written to \f[B]stdout\f[R]. In addition, if history (see the \f[B]HISTORY\f[R] section) and the prompt (see the \f[B]TTY MODE\f[R] section) are enabled, both are output to \f[B]stdout\f[R]. .PP \f[B]Note\f[R]: Unlike other bc(1) implementations, this bc(1) will issue a fatal error (see the \f[B]EXIT STATUS\f[R] section) if it cannot write to \f[B]stdout\f[R], so if \f[B]stdout\f[R] is closed, as in \f[B]bc >&-\f[R], it will quit with an error. This is done so that bc(1) can report problems when \f[B]stdout\f[R] is redirected to a file. .PP If there are scripts that depend on the behavior of other bc(1) implementations, it is recommended that those scripts be changed to redirect \f[B]stdout\f[R] to \f[B]/dev/null\f[R]. .SH STDERR .PP Any error output is written to \f[B]stderr\f[R]. .PP \f[B]Note\f[R]: Unlike other bc(1) implementations, this bc(1) will issue a fatal error (see the \f[B]EXIT STATUS\f[R] section) if it cannot write to \f[B]stderr\f[R], so if \f[B]stderr\f[R] is closed, as in \f[B]bc 2>&-\f[R], it will quit with an error. This is done so that bc(1) can exit with an error code when \f[B]stderr\f[R] is redirected to a file. .PP If there are scripts that depend on the behavior of other bc(1) implementations, it is recommended that those scripts be changed to redirect \f[B]stderr\f[R] to \f[B]/dev/null\f[R]. .SH SYNTAX .PP The syntax for bc(1) programs is mostly C-like, with some differences. This bc(1) follows the POSIX standard (https://pubs.opengroup.org/onlinepubs/9699919799/utilities/bc.html), which is a much more thorough resource for the language this bc(1) accepts. This section is meant to be a summary and a listing of all the extensions to the standard. .PP In the sections below, \f[B]E\f[R] means expression, \f[B]S\f[R] means statement, and \f[B]I\f[R] means identifier. .PP Identifiers (\f[B]I\f[R]) start with a lowercase letter and can be followed by any number (up to \f[B]BC_NAME_MAX-1\f[R]) of lowercase letters (\f[B]a-z\f[R]), digits (\f[B]0-9\f[R]), and underscores (\f[B]_\f[R]). The regex is \f[B][a-z][a-z0-9_]*\f[R]. Identifiers with more than one character (letter) are a \f[B]non-portable extension\f[R]. .PP \f[B]ibase\f[R] is a global variable determining how to interpret constant numbers. It is the \[lq]input\[rq] base, or the number base used for interpreting input numbers. \f[B]ibase\f[R] is initially \f[B]10\f[R]. If the \f[B]-s\f[R] (\f[B]--standard\f[R]) and \f[B]-w\f[R] (\f[B]--warn\f[R]) flags were not given on the command line, the max allowable value for \f[B]ibase\f[R] is \f[B]36\f[R]. Otherwise, it is \f[B]16\f[R]. The min allowable value for \f[B]ibase\f[R] is \f[B]2\f[R]. The max allowable value for \f[B]ibase\f[R] can be queried in bc(1) programs with the \f[B]maxibase()\f[R] built-in function. .PP \f[B]obase\f[R] is a global variable determining how to output results. It is the \[lq]output\[rq] base, or the number base used for outputting numbers. \f[B]obase\f[R] is initially \f[B]10\f[R]. The max allowable value for \f[B]obase\f[R] is \f[B]BC_BASE_MAX\f[R] and can be queried in bc(1) programs with the \f[B]maxobase()\f[R] built-in function. The min allowable value for \f[B]obase\f[R] is \f[B]0\f[R]. If \f[B]obase\f[R] is \f[B]0\f[R], values are output in scientific notation, and if \f[B]obase\f[R] is \f[B]1\f[R], values are output in engineering notation. Otherwise, values are output in the specified base. .PP Outputting in scientific and engineering notations are \f[B]non-portable extensions\f[R]. .PP The \f[I]scale\f[R] of an expression is the number of digits in the result of the expression right of the decimal point, and \f[B]scale\f[R] is a global variable that sets the precision of any operations, with exceptions. \f[B]scale\f[R] is initially \f[B]0\f[R]. \f[B]scale\f[R] cannot be negative. The max allowable value for \f[B]scale\f[R] is \f[B]BC_SCALE_MAX\f[R] and can be queried in bc(1) programs with the \f[B]maxscale()\f[R] built-in function. .PP bc(1) has both \f[I]global\f[R] variables and \f[I]local\f[R] variables. All \f[I]local\f[R] variables are local to the function; they are parameters or are introduced in the \f[B]auto\f[R] list of a function (see the \f[B]FUNCTIONS\f[R] section). If a variable is accessed which is not a parameter or in the \f[B]auto\f[R] list, it is assumed to be \f[I]global\f[R]. If a parent function has a \f[I]local\f[R] variable version of a variable that a child function considers \f[I]global\f[R], the value of that \f[I]global\f[R] variable in the child function is the value of the variable in the parent function, not the value of the actual \f[I]global\f[R] variable. .PP All of the above applies to arrays as well. .PP The value of a statement that is an expression (i.e., any of the named expressions or operands) is printed unless the lowest precedence operator is an assignment operator \f[I]and\f[R] the expression is notsurrounded by parentheses. .PP The value that is printed is also assigned to the special variable \f[B]last\f[R]. A single dot (\f[B].\f[R]) may also be used as a synonym for \f[B]last\f[R]. These are \f[B]non-portable extensions\f[R]. .PP Either semicolons or newlines may separate statements. .SS Comments .PP There are two kinds of comments: .IP "1." 3 Block comments are enclosed in \f[B]/*\f[R] and \f[B]*/\f[R]. .IP "2." 3 Line comments go from \f[B]#\f[R] until, and not including, the next newline. This is a \f[B]non-portable extension\f[R]. .SS Named Expressions .PP The following are named expressions in bc(1): .IP "1." 3 Variables: \f[B]I\f[R] .IP "2." 3 Array Elements: \f[B]I[E]\f[R] .IP "3." 3 \f[B]ibase\f[R] .IP "4." 3 \f[B]obase\f[R] .IP "5." 3 \f[B]scale\f[R] .IP "6." 3 \f[B]seed\f[R] .IP "7." 3 \f[B]last\f[R] or a single dot (\f[B].\f[R]) .PP Numbers 6 and 7 are \f[B]non-portable extensions\f[R]. .PP The meaning of \f[B]seed\f[R] is dependent on the current pseudo-random number generator but is guaranteed to not change except for new major versions. .PP The \f[I]scale\f[R] and sign of the value may be significant. .PP If a previously used \f[B]seed\f[R] value is assigned to \f[B]seed\f[R] and used again, the pseudo-random number generator is guaranteed to produce the same sequence of pseudo-random numbers as it did when the \f[B]seed\f[R] value was previously used. .PP The exact value assigned to \f[B]seed\f[R] is not guaranteed to be returned if \f[B]seed\f[R] is queried again immediately. However, if \f[B]seed\f[R] \f[I]does\f[R] return a different value, both values, when assigned to \f[B]seed\f[R], are guaranteed to produce the same sequence of pseudo-random numbers. This means that certain values assigned to \f[B]seed\f[R] will \f[I]not\f[R] produce unique sequences of pseudo-random numbers. The value of \f[B]seed\f[R] will change after any use of the \f[B]rand()\f[R] and \f[B]irand(E)\f[R] operands (see the \f[I]Operands\f[R] subsection below), except if the parameter passed to \f[B]irand(E)\f[R] is \f[B]0\f[R], \f[B]1\f[R], or negative. .PP There is no limit to the length (number of significant decimal digits) or \f[I]scale\f[R] of the value that can be assigned to \f[B]seed\f[R]. .PP Variables and arrays do not interfere; users can have arrays named the same as variables. This also applies to functions (see the \f[B]FUNCTIONS\f[R] section), so a user can have a variable, array, and function that all have the same name, and they will not shadow each other, whether inside of functions or not. .PP Named expressions are required as the operand of \f[B]increment\f[R]/\f[B]decrement\f[R] operators and as the left side of \f[B]assignment\f[R] operators (see the \f[I]Operators\f[R] subsection). .SS Operands .PP The following are valid operands in bc(1): .IP " 1." 4 Numbers (see the \f[I]Numbers\f[R] subsection below). .IP " 2." 4 Array indices (\f[B]I[E]\f[R]). .IP " 3." 4 \f[B](E)\f[R]: The value of \f[B]E\f[R] (used to change precedence). .IP " 4." 4 \f[B]sqrt(E)\f[R]: The square root of \f[B]E\f[R]. \f[B]E\f[R] must be non-negative. .IP " 5." 4 \f[B]length(E)\f[R]: The number of significant decimal digits in \f[B]E\f[R]. Returns \f[B]1\f[R] for \f[B]0\f[R] with no decimal places. If given a string, the length of the string is returned. Passing a string to \f[B]length(E)\f[R] is a \f[B]non-portable extension\f[R]. .IP " 6." 4 \f[B]length(I[])\f[R]: The number of elements in the array \f[B]I\f[R]. This is a \f[B]non-portable extension\f[R]. .IP " 7." 4 \f[B]scale(E)\f[R]: The \f[I]scale\f[R] of \f[B]E\f[R]. .IP " 8." 4 \f[B]abs(E)\f[R]: The absolute value of \f[B]E\f[R]. This is a \f[B]non-portable extension\f[R]. .IP " 9." 4 \f[B]modexp(E, E, E)\f[R]: Modular exponentiation, where the first expression is the base, the second is the exponent, and the third is the modulus. All three values must be integers. The second argument must be non-negative. The third argument must be non-zero. This is a \f[B]non-portable extension\f[R]. .IP "10." 4 \f[B]divmod(E, E, I[])\f[R]: Division and modulus in one operation. This is for optimization. The first expression is the dividend, and the second is the divisor, which must be non-zero. The return value is the quotient, and the modulus is stored in index \f[B]0\f[R] of the provided array (the last argument). This is a \f[B]non-portable extension\f[R]. .IP "11." 4 \f[B]asciify(E)\f[R]: If \f[B]E\f[R] is a string, returns a string that is the first letter of its argument. If it is a number, calculates the number mod \f[B]256\f[R] and returns that number as a one-character string. This is a \f[B]non-portable extension\f[R]. .IP "12." 4 \f[B]I()\f[R], \f[B]I(E)\f[R], \f[B]I(E, E)\f[R], and so on, where \f[B]I\f[R] is an identifier for a non-\f[B]void\f[R] function (see the \f[I]Void Functions\f[R] subsection of the \f[B]FUNCTIONS\f[R] section). The \f[B]E\f[R] argument(s) may also be arrays of the form \f[B]I[]\f[R], which will automatically be turned into array references (see the \f[I]Array References\f[R] subsection of the \f[B]FUNCTIONS\f[R] section) if the corresponding parameter in the function definition is an array reference. .IP "13." 4 \f[B]read()\f[R]: Reads a line from \f[B]stdin\f[R] and uses that as an expression. The result of that expression is the result of the \f[B]read()\f[R] operand. This is a \f[B]non-portable extension\f[R]. .IP "14." 4 \f[B]maxibase()\f[R]: The max allowable \f[B]ibase\f[R]. This is a \f[B]non-portable extension\f[R]. .IP "15." 4 \f[B]maxobase()\f[R]: The max allowable \f[B]obase\f[R]. This is a \f[B]non-portable extension\f[R]. .IP "16." 4 \f[B]maxscale()\f[R]: The max allowable \f[B]scale\f[R]. This is a \f[B]non-portable extension\f[R]. .IP "17." 4 \f[B]line_length()\f[R]: The line length set with \f[B]BC_LINE_LENGTH\f[R] (see the \f[B]ENVIRONMENT VARIABLES\f[R] section). This is a \f[B]non-portable extension\f[R]. .IP "18." 4 \f[B]global_stacks()\f[R]: \f[B]0\f[R] if global stacks are not enabled with the \f[B]-g\f[R] or \f[B]--global-stacks\f[R] options, non-zero otherwise. See the \f[B]OPTIONS\f[R] section. This is a \f[B]non-portable extension\f[R]. .IP "19." 4 \f[B]leading_zero()\f[R]: \f[B]0\f[R] if leading zeroes are not enabled with the \f[B]-z\f[R] or \f[B]\[en]leading-zeroes\f[R] options, non-zero otherwise. See the \f[B]OPTIONS\f[R] section. This is a \f[B]non-portable extension\f[R]. .IP "20." 4 \f[B]rand()\f[R]: A pseudo-random integer between \f[B]0\f[R] (inclusive) and \f[B]BC_RAND_MAX\f[R] (inclusive). Using this operand will change the value of \f[B]seed\f[R]. This is a \f[B]non-portable extension\f[R]. .IP "21." 4 \f[B]irand(E)\f[R]: A pseudo-random integer between \f[B]0\f[R] (inclusive) and the value of \f[B]E\f[R] (exclusive). If \f[B]E\f[R] is negative or is a non-integer (\f[B]E\f[R]\[cq]s \f[I]scale\f[R] is not \f[B]0\f[R]), an error is raised, and bc(1) resets (see the \f[B]RESET\f[R] section) while \f[B]seed\f[R] remains unchanged. If \f[B]E\f[R] is larger than \f[B]BC_RAND_MAX\f[R], the higher bound is honored by generating several pseudo-random integers, multiplying them by appropriate powers of \f[B]BC_RAND_MAX+1\f[R], and adding them together. Thus, the size of integer that can be generated with this operand is unbounded. Using this operand will change the value of \f[B]seed\f[R], unless the value of \f[B]E\f[R] is \f[B]0\f[R] or \f[B]1\f[R]. In that case, \f[B]0\f[R] is returned, and \f[B]seed\f[R] is \f[I]not\f[R] changed. This is a \f[B]non-portable extension\f[R]. .IP "22." 4 \f[B]maxrand()\f[R]: The max integer returned by \f[B]rand()\f[R]. This is a \f[B]non-portable extension\f[R]. .PP The integers generated by \f[B]rand()\f[R] and \f[B]irand(E)\f[R] are guaranteed to be as unbiased as possible, subject to the limitations of the pseudo-random number generator. .PP \f[B]Note\f[R]: The values returned by the pseudo-random number generator with \f[B]rand()\f[R] and \f[B]irand(E)\f[R] are guaranteed to \f[I]NOT\f[R] be cryptographically secure. This is a consequence of using a seeded pseudo-random number generator. However, they \f[I]are\f[R] guaranteed to be reproducible with identical \f[B]seed\f[R] values. This means that the pseudo-random values from bc(1) should only be used where a reproducible stream of pseudo-random numbers is \f[I]ESSENTIAL\f[R]. In any other case, use a non-seeded pseudo-random number generator. .SS Numbers .PP Numbers are strings made up of digits, uppercase letters, and at most \f[B]1\f[R] period for a radix. Numbers can have up to \f[B]BC_NUM_MAX\f[R] digits. Uppercase letters are equal to \f[B]9\f[R] + their position in the alphabet (i.e., \f[B]A\f[R] equals \f[B]10\f[R], or \f[B]9+1\f[R]). If a digit or letter makes no sense with the current value of \f[B]ibase\f[R], they are set to the value of the highest valid digit in \f[B]ibase\f[R]. .PP Single-character numbers (i.e., \f[B]A\f[R] alone) take the value that they would have if they were valid digits, regardless of the value of \f[B]ibase\f[R]. This means that \f[B]A\f[R] alone always equals decimal \f[B]10\f[R] and \f[B]Z\f[R] alone always equals decimal \f[B]35\f[R]. .PP In addition, bc(1) accepts numbers in scientific notation. These have the form \f[B]e\f[R]. The exponent (the portion after the \f[B]e\f[R]) must be an integer. An example is \f[B]1.89237e9\f[R], which is equal to \f[B]1892370000\f[R]. Negative exponents are also allowed, so \f[B]4.2890e-3\f[R] is equal to \f[B]0.0042890\f[R]. .PP Using scientific notation is an error or warning if the \f[B]-s\f[R] or \f[B]-w\f[R], respectively, command-line options (or equivalents) are given. .PP \f[B]WARNING\f[R]: Both the number and the exponent in scientific notation are interpreted according to the current \f[B]ibase\f[R], but the number is still multiplied by \f[B]10\[ha]exponent\f[R] regardless of the current \f[B]ibase\f[R]. For example, if \f[B]ibase\f[R] is \f[B]16\f[R] and bc(1) is given the number string \f[B]FFeA\f[R], the resulting decimal number will be \f[B]2550000000000\f[R], and if bc(1) is given the number string \f[B]10e-4\f[R], the resulting decimal number will be \f[B]0.0016\f[R]. .PP Accepting input as scientific notation is a \f[B]non-portable extension\f[R]. .SS Operators .PP The following arithmetic and logical operators can be used. They are listed in order of decreasing precedence. Operators in the same group have the same precedence. .TP \f[B]++\f[R] \f[B]--\f[R] Type: Prefix and Postfix .RS .PP Associativity: None .PP Description: \f[B]increment\f[R], \f[B]decrement\f[R] .RE .TP \f[B]-\f[R] \f[B]!\f[R] Type: Prefix .RS .PP Associativity: None .PP Description: \f[B]negation\f[R], \f[B]boolean not\f[R] .RE .TP \f[B]$\f[R] Type: Postfix .RS .PP Associativity: None .PP Description: \f[B]truncation\f[R] .RE .TP \f[B]\[at]\f[R] Type: Binary .RS .PP Associativity: Right .PP Description: \f[B]set precision\f[R] .RE .TP \f[B]\[ha]\f[R] Type: Binary .RS .PP Associativity: Right .PP Description: \f[B]power\f[R] .RE .TP \f[B]*\f[R] \f[B]/\f[R] \f[B]%\f[R] Type: Binary .RS .PP Associativity: Left .PP Description: \f[B]multiply\f[R], \f[B]divide\f[R], \f[B]modulus\f[R] .RE .TP \f[B]+\f[R] \f[B]-\f[R] Type: Binary .RS .PP Associativity: Left .PP Description: \f[B]add\f[R], \f[B]subtract\f[R] .RE .TP \f[B]<<\f[R] \f[B]>>\f[R] Type: Binary .RS .PP Associativity: Left .PP Description: \f[B]shift left\f[R], \f[B]shift right\f[R] .RE .TP \f[B]=\f[R] \f[B]<<=\f[R] \f[B]>>=\f[R] \f[B]+=\f[R] \f[B]-=\f[R] \f[B]*=\f[R] \f[B]/=\f[R] \f[B]%=\f[R] \f[B]\[ha]=\f[R] \f[B]\[at]=\f[R] Type: Binary .RS .PP Associativity: Right .PP Description: \f[B]assignment\f[R] .RE .TP \f[B]==\f[R] \f[B]<=\f[R] \f[B]>=\f[R] \f[B]!=\f[R] \f[B]<\f[R] \f[B]>\f[R] Type: Binary .RS .PP Associativity: Left .PP Description: \f[B]relational\f[R] .RE .TP \f[B]&&\f[R] Type: Binary .RS .PP Associativity: Left .PP Description: \f[B]boolean and\f[R] .RE .TP \f[B]||\f[R] Type: Binary .RS .PP Associativity: Left .PP Description: \f[B]boolean or\f[R] .RE .PP The operators will be described in more detail below. .TP \f[B]++\f[R] \f[B]--\f[R] The prefix and postfix \f[B]increment\f[R] and \f[B]decrement\f[R] operators behave exactly like they would in C. They require a named expression (see the \f[I]Named Expressions\f[R] subsection) as an operand. .RS .PP The prefix versions of these operators are more efficient; use them where possible. .RE .TP \f[B]-\f[R] The \f[B]negation\f[R] operator returns \f[B]0\f[R] if a user attempts to negate any expression with the value \f[B]0\f[R]. Otherwise, a copy of the expression with its sign flipped is returned. .TP \f[B]!\f[R] The \f[B]boolean not\f[R] operator returns \f[B]1\f[R] if the expression is \f[B]0\f[R], or \f[B]0\f[R] otherwise. .RS .PP This is a \f[B]non-portable extension\f[R]. .RE .TP \f[B]$\f[R] The \f[B]truncation\f[R] operator returns a copy of the given expression with all of its \f[I]scale\f[R] removed. .RS .PP This is a \f[B]non-portable extension\f[R]. .RE .TP \f[B]\[at]\f[R] The \f[B]set precision\f[R] operator takes two expressions and returns a copy of the first with its \f[I]scale\f[R] equal to the value of the second expression. That could either mean that the number is returned without change (if the \f[I]scale\f[R] of the first expression matches the value of the second expression), extended (if it is less), or truncated (if it is more). .RS .PP The second expression must be an integer (no \f[I]scale\f[R]) and non-negative. .PP This is a \f[B]non-portable extension\f[R]. .RE .TP \f[B]\[ha]\f[R] The \f[B]power\f[R] operator (not the \f[B]exclusive or\f[R] operator, as it would be in C) takes two expressions and raises the first to the power of the value of the second. The \f[I]scale\f[R] of the result is equal to \f[B]scale\f[R]. .RS .PP The second expression must be an integer (no \f[I]scale\f[R]), and if it is negative, the first value must be non-zero. .RE .TP \f[B]*\f[R] The \f[B]multiply\f[R] operator takes two expressions, multiplies them, and returns the product. If \f[B]a\f[R] is the \f[I]scale\f[R] of the first expression and \f[B]b\f[R] is the \f[I]scale\f[R] of the second expression, the \f[I]scale\f[R] of the result is equal to \f[B]min(a+b,max(scale,a,b))\f[R] where \f[B]min()\f[R] and \f[B]max()\f[R] return the obvious values. .TP \f[B]/\f[R] The \f[B]divide\f[R] operator takes two expressions, divides them, and returns the quotient. The \f[I]scale\f[R] of the result shall be the value of \f[B]scale\f[R]. .RS .PP The second expression must be non-zero. .RE .TP \f[B]%\f[R] The \f[B]modulus\f[R] operator takes two expressions, \f[B]a\f[R] and \f[B]b\f[R], and evaluates them by 1) Computing \f[B]a/b\f[R] to current \f[B]scale\f[R] and 2) Using the result of step 1 to calculate \f[B]a-(a/b)*b\f[R] to \f[I]scale\f[R] \f[B]max(scale+scale(b),scale(a))\f[R]. .RS .PP The second expression must be non-zero. .RE .TP \f[B]+\f[R] The \f[B]add\f[R] operator takes two expressions, \f[B]a\f[R] and \f[B]b\f[R], and returns the sum, with a \f[I]scale\f[R] equal to the max of the \f[I]scale\f[R]s of \f[B]a\f[R] and \f[B]b\f[R]. .TP \f[B]-\f[R] The \f[B]subtract\f[R] operator takes two expressions, \f[B]a\f[R] and \f[B]b\f[R], and returns the difference, with a \f[I]scale\f[R] equal to the max of the \f[I]scale\f[R]s of \f[B]a\f[R] and \f[B]b\f[R]. .TP \f[B]<<\f[R] The \f[B]left shift\f[R] operator takes two expressions, \f[B]a\f[R] and \f[B]b\f[R], and returns a copy of the value of \f[B]a\f[R] with its decimal point moved \f[B]b\f[R] places to the right. .RS .PP The second expression must be an integer (no \f[I]scale\f[R]) and non-negative. .PP This is a \f[B]non-portable extension\f[R]. .RE .TP \f[B]>>\f[R] The \f[B]right shift\f[R] operator takes two expressions, \f[B]a\f[R] and \f[B]b\f[R], and returns a copy of the value of \f[B]a\f[R] with its decimal point moved \f[B]b\f[R] places to the left. .RS .PP The second expression must be an integer (no \f[I]scale\f[R]) and non-negative. .PP This is a \f[B]non-portable extension\f[R]. .RE .TP \f[B]=\f[R] \f[B]<<=\f[R] \f[B]>>=\f[R] \f[B]+=\f[R] \f[B]-=\f[R] \f[B]*=\f[R] \f[B]/=\f[R] \f[B]%=\f[R] \f[B]\[ha]=\f[R] \f[B]\[at]=\f[R] The \f[B]assignment\f[R] operators take two expressions, \f[B]a\f[R] and \f[B]b\f[R] where \f[B]a\f[R] is a named expression (see the \f[I]Named Expressions\f[R] subsection). .RS .PP For \f[B]=\f[R], \f[B]b\f[R] is copied and the result is assigned to \f[B]a\f[R]. For all others, \f[B]a\f[R] and \f[B]b\f[R] are applied as operands to the corresponding arithmetic operator and the result is assigned to \f[B]a\f[R]. .PP The \f[B]assignment\f[R] operators that correspond to operators that are extensions are themselves \f[B]non-portable extensions\f[R]. .RE .TP \f[B]==\f[R] \f[B]<=\f[R] \f[B]>=\f[R] \f[B]!=\f[R] \f[B]<\f[R] \f[B]>\f[R] The \f[B]relational\f[R] operators compare two expressions, \f[B]a\f[R] and \f[B]b\f[R], and if the relation holds, according to C language semantics, the result is \f[B]1\f[R]. Otherwise, it is \f[B]0\f[R]. .RS .PP Note that unlike in C, these operators have a lower precedence than the \f[B]assignment\f[R] operators, which means that \f[B]a=b>c\f[R] is interpreted as \f[B](a=b)>c\f[R]. .PP Also, unlike the standard (https://pubs.opengroup.org/onlinepubs/9699919799/utilities/bc.html) requires, these operators can appear anywhere any other expressions can be used. This allowance is a \f[B]non-portable extension\f[R]. .RE .TP \f[B]&&\f[R] The \f[B]boolean and\f[R] operator takes two expressions and returns \f[B]1\f[R] if both expressions are non-zero, \f[B]0\f[R] otherwise. .RS .PP This is \f[I]not\f[R] a short-circuit operator. .PP This is a \f[B]non-portable extension\f[R]. .RE .TP \f[B]||\f[R] The \f[B]boolean or\f[R] operator takes two expressions and returns \f[B]1\f[R] if one of the expressions is non-zero, \f[B]0\f[R] otherwise. .RS .PP This is \f[I]not\f[R] a short-circuit operator. .PP This is a \f[B]non-portable extension\f[R]. .RE .SS Statements .PP The following items are statements: .IP " 1." 4 \f[B]E\f[R] .IP " 2." 4 \f[B]{\f[R] \f[B]S\f[R] \f[B];\f[R] \&... \f[B];\f[R] \f[B]S\f[R] \f[B]}\f[R] .IP " 3." 4 \f[B]if\f[R] \f[B](\f[R] \f[B]E\f[R] \f[B])\f[R] \f[B]S\f[R] .IP " 4." 4 \f[B]if\f[R] \f[B](\f[R] \f[B]E\f[R] \f[B])\f[R] \f[B]S\f[R] \f[B]else\f[R] \f[B]S\f[R] .IP " 5." 4 \f[B]while\f[R] \f[B](\f[R] \f[B]E\f[R] \f[B])\f[R] \f[B]S\f[R] .IP " 6." 4 \f[B]for\f[R] \f[B](\f[R] \f[B]E\f[R] \f[B];\f[R] \f[B]E\f[R] \f[B];\f[R] \f[B]E\f[R] \f[B])\f[R] \f[B]S\f[R] .IP " 7." 4 An empty statement .IP " 8." 4 \f[B]break\f[R] .IP " 9." 4 \f[B]continue\f[R] .IP "10." 4 \f[B]quit\f[R] .IP "11." 4 \f[B]halt\f[R] .IP "12." 4 \f[B]limits\f[R] .IP "13." 4 A string of characters, enclosed in double quotes .IP "14." 4 \f[B]print\f[R] \f[B]E\f[R] \f[B],\f[R] \&... \f[B],\f[R] \f[B]E\f[R] .IP "15." 4 \f[B]stream\f[R] \f[B]E\f[R] \f[B],\f[R] \&... \f[B],\f[R] \f[B]E\f[R] .IP "16." 4 \f[B]I()\f[R], \f[B]I(E)\f[R], \f[B]I(E, E)\f[R], and so on, where \f[B]I\f[R] is an identifier for a \f[B]void\f[R] function (see the \f[I]Void Functions\f[R] subsection of the \f[B]FUNCTIONS\f[R] section). The \f[B]E\f[R] argument(s) may also be arrays of the form \f[B]I[]\f[R], which will automatically be turned into array references (see the \f[I]Array References\f[R] subsection of the \f[B]FUNCTIONS\f[R] section) if the corresponding parameter in the function definition is an array reference. .PP Numbers 4, 9, 11, 12, 14, 15, and 16 are \f[B]non-portable extensions\f[R]. .PP Also, as a \f[B]non-portable extension\f[R], any or all of the expressions in the header of a for loop may be omitted. If the condition (second expression) is omitted, it is assumed to be a constant \f[B]1\f[R]. .PP The \f[B]break\f[R] statement causes a loop to stop iterating and resume execution immediately following a loop. This is only allowed in loops. .PP The \f[B]continue\f[R] statement causes a loop iteration to stop early and returns to the start of the loop, including testing the loop condition. This is only allowed in loops. .PP The \f[B]if\f[R] \f[B]else\f[R] statement does the same thing as in C. .PP The \f[B]quit\f[R] statement causes bc(1) to quit, even if it is on a branch that will not be executed (it is a compile-time command). .PP The \f[B]halt\f[R] statement causes bc(1) to quit, if it is executed. (Unlike \f[B]quit\f[R] if it is on a branch of an \f[B]if\f[R] statement that is not executed, bc(1) does not quit.) .PP The \f[B]limits\f[R] statement prints the limits that this bc(1) is subject to. This is like the \f[B]quit\f[R] statement in that it is a compile-time command. .PP An expression by itself is evaluated and printed, followed by a newline. .PP Both scientific notation and engineering notation are available for printing the results of expressions. Scientific notation is activated by assigning \f[B]0\f[R] to \f[B]obase\f[R], and engineering notation is activated by assigning \f[B]1\f[R] to \f[B]obase\f[R]. To deactivate them, just assign a different value to \f[B]obase\f[R]. .PP Scientific notation and engineering notation are disabled if bc(1) is run with either the \f[B]-s\f[R] or \f[B]-w\f[R] command-line options (or equivalents). .PP Printing numbers in scientific notation and/or engineering notation is a \f[B]non-portable extension\f[R]. .SS Strings .PP If strings appear as a statement by themselves, they are printed without a trailing newline. .PP In addition to appearing as a lone statement by themselves, strings can be assigned to variables and array elements. They can also be passed to functions in variable parameters. .PP If any statement that expects a string is given a variable that had a string assigned to it, the statement acts as though it had received a string. .PP If any math operation is attempted on a string or a variable or array element that has been assigned a string, an error is raised, and bc(1) resets (see the \f[B]RESET\f[R] section). .PP Assigning strings to variables and array elements and passing them to functions are \f[B]non-portable extensions\f[R]. .SS Print Statement .PP The \[lq]expressions\[rq] in a \f[B]print\f[R] statement may also be strings. If they are, there are backslash escape sequences that are interpreted specially. What those sequences are, and what they cause to be printed, are shown below: .PP \f[B]\[rs]a\f[R]: \f[B]\[rs]a\f[R] .PP \f[B]\[rs]b\f[R]: \f[B]\[rs]b\f[R] .PP \f[B]\[rs]\[rs]\f[R]: \f[B]\[rs]\f[R] .PP \f[B]\[rs]e\f[R]: \f[B]\[rs]\f[R] .PP \f[B]\[rs]f\f[R]: \f[B]\[rs]f\f[R] .PP \f[B]\[rs]n\f[R]: \f[B]\[rs]n\f[R] .PP \f[B]\[rs]q\f[R]: \f[B]\[lq]\f[R] .PP \f[B]\[rs]r\f[R]: \f[B]\[rs]r\f[R] .PP \f[B]\[rs]t\f[R]: \f[B]\[rs]t\f[R] .PP Any other character following a backslash causes the backslash and character to be printed as-is. .PP Any non-string expression in a print statement shall be assigned to \f[B]last\f[R], like any other expression that is printed. .SS Stream Statement .PP The \[lq]expressions in a \f[B]stream\f[R] statement may also be strings. .PP If a \f[B]stream\f[R] statement is given a string, it prints the string as though the string had appeared as its own statement. In other words, the \f[B]stream\f[R] statement prints strings normally, without a newline. .PP If a \f[B]stream\f[R] statement is given a number, a copy of it is truncated and its absolute value is calculated. The result is then printed as though \f[B]obase\f[R] is \f[B]256\f[R] and each digit is interpreted as an 8-bit ASCII character, making it a byte stream. .SS Order of Evaluation .PP All expressions in a statment are evaluated left to right, except as necessary to maintain order of operations. This means, for example, assuming that \f[B]i\f[R] is equal to \f[B]0\f[R], in the expression .IP .nf \f[C] a[i++] = i++ \f[R] .fi .PP the first (or 0th) element of \f[B]a\f[R] is set to \f[B]1\f[R], and \f[B]i\f[R] is equal to \f[B]2\f[R] at the end of the expression. .PP This includes function arguments. Thus, assuming \f[B]i\f[R] is equal to \f[B]0\f[R], this means that in the expression .IP .nf \f[C] x(i++, i++) \f[R] .fi .PP the first argument passed to \f[B]x()\f[R] is \f[B]0\f[R], and the second argument is \f[B]1\f[R], while \f[B]i\f[R] is equal to \f[B]2\f[R] before the function starts executing. .SH FUNCTIONS .PP Function definitions are as follows: .IP .nf \f[C] define I(I,...,I){ auto I,...,I S;...;S return(E) } \f[R] .fi .PP Any \f[B]I\f[R] in the parameter list or \f[B]auto\f[R] list may be replaced with \f[B]I[]\f[R] to make a parameter or \f[B]auto\f[R] var an array, and any \f[B]I\f[R] in the parameter list may be replaced with \f[B]*I[]\f[R] to make a parameter an array reference. Callers of functions that take array references should not put an asterisk in the call; they must be called with just \f[B]I[]\f[R] like normal array parameters and will be automatically converted into references. .PP As a \f[B]non-portable extension\f[R], the opening brace of a \f[B]define\f[R] statement may appear on the next line. .PP As a \f[B]non-portable extension\f[R], the return statement may also be in one of the following forms: .IP "1." 3 \f[B]return\f[R] .IP "2." 3 \f[B]return\f[R] \f[B](\f[R] \f[B])\f[R] .IP "3." 3 \f[B]return\f[R] \f[B]E\f[R] .PP The first two, or not specifying a \f[B]return\f[R] statement, is equivalent to \f[B]return (0)\f[R], unless the function is a \f[B]void\f[R] function (see the \f[I]Void Functions\f[R] subsection below). .SS Void Functions .PP Functions can also be \f[B]void\f[R] functions, defined as follows: .IP .nf \f[C] define void I(I,...,I){ auto I,...,I S;...;S return } \f[R] .fi .PP They can only be used as standalone expressions, where such an expression would be printed alone, except in a print statement. .PP Void functions can only use the first two \f[B]return\f[R] statements listed above. They can also omit the return statement entirely. .PP The word \[lq]void\[rq] is not treated as a keyword; it is still possible to have variables, arrays, and functions named \f[B]void\f[R]. The word \[lq]void\[rq] is only treated specially right after the \f[B]define\f[R] keyword. .PP This is a \f[B]non-portable extension\f[R]. .SS Array References .PP For any array in the parameter list, if the array is declared in the form .IP .nf \f[C] *I[] \f[R] .fi .PP it is a \f[B]reference\f[R]. Any changes to the array in the function are reflected, when the function returns, to the array that was passed in. .PP Other than this, all function arguments are passed by value. .PP This is a \f[B]non-portable extension\f[R]. .SH LIBRARY .PP All of the functions below, including the functions in the extended math library (see the \f[I]Extended Library\f[R] subsection below), are available when the \f[B]-l\f[R] or \f[B]--mathlib\f[R] command-line flags are given, except that the extended math library is not available when the \f[B]-s\f[R] option, the \f[B]-w\f[R] option, or equivalents are given. .SS Standard Library .PP The standard (https://pubs.opengroup.org/onlinepubs/9699919799/utilities/bc.html) defines the following functions for the math library: .TP \f[B]s(x)\f[R] Returns the sine of \f[B]x\f[R], which is assumed to be in radians. .RS .PP This is a transcendental function (see the \f[I]Transcendental Functions\f[R] subsection below). .RE .TP \f[B]c(x)\f[R] Returns the cosine of \f[B]x\f[R], which is assumed to be in radians. .RS .PP This is a transcendental function (see the \f[I]Transcendental Functions\f[R] subsection below). .RE .TP \f[B]a(x)\f[R] Returns the arctangent of \f[B]x\f[R], in radians. .RS .PP This is a transcendental function (see the \f[I]Transcendental Functions\f[R] subsection below). .RE .TP \f[B]l(x)\f[R] Returns the natural logarithm of \f[B]x\f[R]. .RS .PP This is a transcendental function (see the \f[I]Transcendental Functions\f[R] subsection below). .RE .TP \f[B]e(x)\f[R] Returns the mathematical constant \f[B]e\f[R] raised to the power of \f[B]x\f[R]. .RS .PP This is a transcendental function (see the \f[I]Transcendental Functions\f[R] subsection below). .RE .TP \f[B]j(x, n)\f[R] Returns the bessel integer order \f[B]n\f[R] (truncated) of \f[B]x\f[R]. .RS .PP This is a transcendental function (see the \f[I]Transcendental Functions\f[R] subsection below). .RE .SS Extended Library .PP The extended library is \f[I]not\f[R] loaded when the \f[B]-s\f[R]/\f[B]--standard\f[R] or \f[B]-w\f[R]/\f[B]--warn\f[R] options are given since they are not part of the library defined by the standard (https://pubs.opengroup.org/onlinepubs/9699919799/utilities/bc.html). .PP The extended library is a \f[B]non-portable extension\f[R]. .TP \f[B]p(x, y)\f[R] Calculates \f[B]x\f[R] to the power of \f[B]y\f[R], even if \f[B]y\f[R] is not an integer, and returns the result to the current \f[B]scale\f[R]. .RS .PP It is an error if \f[B]y\f[R] is negative and \f[B]x\f[R] is \f[B]0\f[R]. .PP This is a transcendental function (see the \f[I]Transcendental Functions\f[R] subsection below). .RE .TP \f[B]r(x, p)\f[R] Returns \f[B]x\f[R] rounded to \f[B]p\f[R] decimal places according to the rounding mode round half away from \f[B]0\f[R] (https://en.wikipedia.org/wiki/Rounding#Round_half_away_from_zero). .TP \f[B]ceil(x, p)\f[R] Returns \f[B]x\f[R] rounded to \f[B]p\f[R] decimal places according to the rounding mode round away from \f[B]0\f[R] (https://en.wikipedia.org/wiki/Rounding#Rounding_away_from_zero). .TP \f[B]f(x)\f[R] Returns the factorial of the truncated absolute value of \f[B]x\f[R]. .TP \f[B]perm(n, k)\f[R] Returns the permutation of the truncated absolute value of \f[B]n\f[R] of the truncated absolute value of \f[B]k\f[R], if \f[B]k <= n\f[R]. If not, it returns \f[B]0\f[R]. .TP \f[B]comb(n, k)\f[R] Returns the combination of the truncated absolute value of \f[B]n\f[R] of the truncated absolute value of \f[B]k\f[R], if \f[B]k <= n\f[R]. If not, it returns \f[B]0\f[R]. .TP \f[B]l2(x)\f[R] Returns the logarithm base \f[B]2\f[R] of \f[B]x\f[R]. .RS .PP This is a transcendental function (see the \f[I]Transcendental Functions\f[R] subsection below). .RE .TP \f[B]l10(x)\f[R] Returns the logarithm base \f[B]10\f[R] of \f[B]x\f[R]. .RS .PP This is a transcendental function (see the \f[I]Transcendental Functions\f[R] subsection below). .RE .TP \f[B]log(x, b)\f[R] Returns the logarithm base \f[B]b\f[R] of \f[B]x\f[R]. .RS .PP This is a transcendental function (see the \f[I]Transcendental Functions\f[R] subsection below). .RE .TP \f[B]cbrt(x)\f[R] Returns the cube root of \f[B]x\f[R]. .TP \f[B]root(x, n)\f[R] Calculates the truncated value of \f[B]n\f[R], \f[B]r\f[R], and returns the \f[B]r\f[R]th root of \f[B]x\f[R] to the current \f[B]scale\f[R]. .RS .PP If \f[B]r\f[R] is \f[B]0\f[R] or negative, this raises an error and causes bc(1) to reset (see the \f[B]RESET\f[R] section). It also raises an error and causes bc(1) to reset if \f[B]r\f[R] is even and \f[B]x\f[R] is negative. .RE .TP \f[B]gcd(a, b)\f[R] Returns the greatest common divisor (factor) of the truncated absolute value of \f[B]a\f[R] and the truncated absolute value of \f[B]b\f[R]. .TP \f[B]lcm(a, b)\f[R] Returns the least common multiple of the truncated absolute value of \f[B]a\f[R] and the truncated absolute value of \f[B]b\f[R]. .TP \f[B]pi(p)\f[R] Returns \f[B]pi\f[R] to \f[B]p\f[R] decimal places. .RS .PP This is a transcendental function (see the \f[I]Transcendental Functions\f[R] subsection below). .RE .TP \f[B]t(x)\f[R] Returns the tangent of \f[B]x\f[R], which is assumed to be in radians. .RS .PP This is a transcendental function (see the \f[I]Transcendental Functions\f[R] subsection below). .RE .TP \f[B]a2(y, x)\f[R] Returns the arctangent of \f[B]y/x\f[R], in radians. If both \f[B]y\f[R] and \f[B]x\f[R] are equal to \f[B]0\f[R], it raises an error and causes bc(1) to reset (see the \f[B]RESET\f[R] section). Otherwise, if \f[B]x\f[R] is greater than \f[B]0\f[R], it returns \f[B]a(y/x)\f[R]. If \f[B]x\f[R] is less than \f[B]0\f[R], and \f[B]y\f[R] is greater than or equal to \f[B]0\f[R], it returns \f[B]a(y/x)+pi\f[R]. If \f[B]x\f[R] is less than \f[B]0\f[R], and \f[B]y\f[R] is less than \f[B]0\f[R], it returns \f[B]a(y/x)-pi\f[R]. If \f[B]x\f[R] is equal to \f[B]0\f[R], and \f[B]y\f[R] is greater than \f[B]0\f[R], it returns \f[B]pi/2\f[R]. If \f[B]x\f[R] is equal to \f[B]0\f[R], and \f[B]y\f[R] is less than \f[B]0\f[R], it returns \f[B]-pi/2\f[R]. .RS .PP This function is the same as the \f[B]atan2()\f[R] function in many programming languages. .PP This is a transcendental function (see the \f[I]Transcendental Functions\f[R] subsection below). .RE .TP \f[B]sin(x)\f[R] Returns the sine of \f[B]x\f[R], which is assumed to be in radians. .RS .PP This is an alias of \f[B]s(x)\f[R]. .PP This is a transcendental function (see the \f[I]Transcendental Functions\f[R] subsection below). .RE .TP \f[B]cos(x)\f[R] Returns the cosine of \f[B]x\f[R], which is assumed to be in radians. .RS .PP This is an alias of \f[B]c(x)\f[R]. .PP This is a transcendental function (see the \f[I]Transcendental Functions\f[R] subsection below). .RE .TP \f[B]tan(x)\f[R] Returns the tangent of \f[B]x\f[R], which is assumed to be in radians. .RS .PP If \f[B]x\f[R] is equal to \f[B]1\f[R] or \f[B]-1\f[R], this raises an error and causes bc(1) to reset (see the \f[B]RESET\f[R] section). .PP This is an alias of \f[B]t(x)\f[R]. .PP This is a transcendental function (see the \f[I]Transcendental Functions\f[R] subsection below). .RE .TP \f[B]atan(x)\f[R] Returns the arctangent of \f[B]x\f[R], in radians. .RS .PP This is an alias of \f[B]a(x)\f[R]. .PP This is a transcendental function (see the \f[I]Transcendental Functions\f[R] subsection below). .RE .TP \f[B]atan2(y, x)\f[R] Returns the arctangent of \f[B]y/x\f[R], in radians. If both \f[B]y\f[R] and \f[B]x\f[R] are equal to \f[B]0\f[R], it raises an error and causes bc(1) to reset (see the \f[B]RESET\f[R] section). Otherwise, if \f[B]x\f[R] is greater than \f[B]0\f[R], it returns \f[B]a(y/x)\f[R]. If \f[B]x\f[R] is less than \f[B]0\f[R], and \f[B]y\f[R] is greater than or equal to \f[B]0\f[R], it returns \f[B]a(y/x)+pi\f[R]. If \f[B]x\f[R] is less than \f[B]0\f[R], and \f[B]y\f[R] is less than \f[B]0\f[R], it returns \f[B]a(y/x)-pi\f[R]. If \f[B]x\f[R] is equal to \f[B]0\f[R], and \f[B]y\f[R] is greater than \f[B]0\f[R], it returns \f[B]pi/2\f[R]. If \f[B]x\f[R] is equal to \f[B]0\f[R], and \f[B]y\f[R] is less than \f[B]0\f[R], it returns \f[B]-pi/2\f[R]. .RS .PP This function is the same as the \f[B]atan2()\f[R] function in many programming languages. .PP This is an alias of \f[B]a2(y, x)\f[R]. .PP This is a transcendental function (see the \f[I]Transcendental Functions\f[R] subsection below). .RE .TP \f[B]r2d(x)\f[R] Converts \f[B]x\f[R] from radians to degrees and returns the result. .RS .PP This is a transcendental function (see the \f[I]Transcendental Functions\f[R] subsection below). .RE .TP \f[B]d2r(x)\f[R] Converts \f[B]x\f[R] from degrees to radians and returns the result. .RS .PP This is a transcendental function (see the \f[I]Transcendental Functions\f[R] subsection below). .RE .TP \f[B]frand(p)\f[R] Generates a pseudo-random number between \f[B]0\f[R] (inclusive) and \f[B]1\f[R] (exclusive) with the number of decimal digits after the decimal point equal to the truncated absolute value of \f[B]p\f[R]. If \f[B]p\f[R] is not \f[B]0\f[R], then calling this function will change the value of \f[B]seed\f[R]. If \f[B]p\f[R] is \f[B]0\f[R], then \f[B]0\f[R] is returned, and \f[B]seed\f[R] is \f[I]not\f[R] changed. .TP \f[B]ifrand(i, p)\f[R] Generates a pseudo-random number that is between \f[B]0\f[R] (inclusive) and the truncated absolute value of \f[B]i\f[R] (exclusive) with the number of decimal digits after the decimal point equal to the truncated absolute value of \f[B]p\f[R]. If the absolute value of \f[B]i\f[R] is greater than or equal to \f[B]2\f[R], and \f[B]p\f[R] is not \f[B]0\f[R], then calling this function will change the value of \f[B]seed\f[R]; otherwise, \f[B]0\f[R] is returned and \f[B]seed\f[R] is not changed. .TP \f[B]srand(x)\f[R] Returns \f[B]x\f[R] with its sign flipped with probability \f[B]0.5\f[R]. In other words, it randomizes the sign of \f[B]x\f[R]. .TP \f[B]brand()\f[R] Returns a random boolean value (either \f[B]0\f[R] or \f[B]1\f[R]). .TP \f[B]band(a, b)\f[R] Takes the truncated absolute value of both \f[B]a\f[R] and \f[B]b\f[R] and calculates and returns the result of the bitwise \f[B]and\f[R] operation between them. .RS .PP If you want to use signed two\[cq]s complement arguments, use \f[B]s2u(x)\f[R] to convert. .RE .TP \f[B]bor(a, b)\f[R] Takes the truncated absolute value of both \f[B]a\f[R] and \f[B]b\f[R] and calculates and returns the result of the bitwise \f[B]or\f[R] operation between them. .RS .PP If you want to use signed two\[cq]s complement arguments, use \f[B]s2u(x)\f[R] to convert. .RE .TP \f[B]bxor(a, b)\f[R] Takes the truncated absolute value of both \f[B]a\f[R] and \f[B]b\f[R] and calculates and returns the result of the bitwise \f[B]xor\f[R] operation between them. .RS .PP If you want to use signed two\[cq]s complement arguments, use \f[B]s2u(x)\f[R] to convert. .RE .TP \f[B]bshl(a, b)\f[R] Takes the truncated absolute value of both \f[B]a\f[R] and \f[B]b\f[R] and calculates and returns the result of \f[B]a\f[R] bit-shifted left by \f[B]b\f[R] places. .RS .PP If you want to use signed two\[cq]s complement arguments, use \f[B]s2u(x)\f[R] to convert. .RE .TP \f[B]bshr(a, b)\f[R] Takes the truncated absolute value of both \f[B]a\f[R] and \f[B]b\f[R] and calculates and returns the truncated result of \f[B]a\f[R] bit-shifted right by \f[B]b\f[R] places. .RS .PP If you want to use signed two\[cq]s complement arguments, use \f[B]s2u(x)\f[R] to convert. .RE .TP \f[B]bnotn(x, n)\f[R] Takes the truncated absolute value of \f[B]x\f[R] and does a bitwise not as though it has the same number of bytes as the truncated absolute value of \f[B]n\f[R]. .RS .PP If you want to a use signed two\[cq]s complement argument, use \f[B]s2u(x)\f[R] to convert. .RE .TP \f[B]bnot8(x)\f[R] Does a bitwise not of the truncated absolute value of \f[B]x\f[R] as though it has \f[B]8\f[R] binary digits (1 unsigned byte). .RS .PP If you want to a use signed two\[cq]s complement argument, use \f[B]s2u(x)\f[R] to convert. .RE .TP \f[B]bnot16(x)\f[R] Does a bitwise not of the truncated absolute value of \f[B]x\f[R] as though it has \f[B]16\f[R] binary digits (2 unsigned bytes). .RS .PP If you want to a use signed two\[cq]s complement argument, use \f[B]s2u(x)\f[R] to convert. .RE .TP \f[B]bnot32(x)\f[R] Does a bitwise not of the truncated absolute value of \f[B]x\f[R] as though it has \f[B]32\f[R] binary digits (4 unsigned bytes). .RS .PP If you want to a use signed two\[cq]s complement argument, use \f[B]s2u(x)\f[R] to convert. .RE .TP \f[B]bnot64(x)\f[R] Does a bitwise not of the truncated absolute value of \f[B]x\f[R] as though it has \f[B]64\f[R] binary digits (8 unsigned bytes). .RS .PP If you want to a use signed two\[cq]s complement argument, use \f[B]s2u(x)\f[R] to convert. .RE .TP \f[B]bnot(x)\f[R] Does a bitwise not of the truncated absolute value of \f[B]x\f[R] as though it has the minimum number of power of two unsigned bytes. .RS .PP If you want to a use signed two\[cq]s complement argument, use \f[B]s2u(x)\f[R] to convert. .RE .TP \f[B]brevn(x, n)\f[R] Runs a bit reversal on the truncated absolute value of \f[B]x\f[R] as though it has the same number of 8-bit bytes as the truncated absolute value of \f[B]n\f[R]. .RS .PP If you want to a use signed two\[cq]s complement argument, use \f[B]s2u(x)\f[R] to convert. .RE .TP \f[B]brev8(x)\f[R] Runs a bit reversal on the truncated absolute value of \f[B]x\f[R] as though it has 8 binary digits (1 unsigned byte). .RS .PP If you want to a use signed two\[cq]s complement argument, use \f[B]s2u(x)\f[R] to convert. .RE .TP \f[B]brev16(x)\f[R] Runs a bit reversal on the truncated absolute value of \f[B]x\f[R] as though it has 16 binary digits (2 unsigned bytes). .RS .PP If you want to a use signed two\[cq]s complement argument, use \f[B]s2u(x)\f[R] to convert. .RE .TP \f[B]brev32(x)\f[R] Runs a bit reversal on the truncated absolute value of \f[B]x\f[R] as though it has 32 binary digits (4 unsigned bytes). .RS .PP If you want to a use signed two\[cq]s complement argument, use \f[B]s2u(x)\f[R] to convert. .RE .TP \f[B]brev64(x)\f[R] Runs a bit reversal on the truncated absolute value of \f[B]x\f[R] as though it has 64 binary digits (8 unsigned bytes). .RS .PP If you want to a use signed two\[cq]s complement argument, use \f[B]s2u(x)\f[R] to convert. .RE .TP \f[B]brev(x)\f[R] Runs a bit reversal on the truncated absolute value of \f[B]x\f[R] as though it has the minimum number of power of two unsigned bytes. .RS .PP If you want to a use signed two\[cq]s complement argument, use \f[B]s2u(x)\f[R] to convert. .RE .TP \f[B]broln(x, p, n)\f[R] Does a left bitwise rotatation of the truncated absolute value of \f[B]x\f[R], as though it has the same number of unsigned 8-bit bytes as the truncated absolute value of \f[B]n\f[R], by the number of places equal to the truncated absolute value of \f[B]p\f[R] modded by the \f[B]2\f[R] to the power of the number of binary digits in \f[B]n\f[R] 8-bit bytes. .RS .PP If you want to a use signed two\[cq]s complement argument, use \f[B]s2u(x)\f[R] to convert. .RE .TP \f[B]brol8(x, p)\f[R] Does a left bitwise rotatation of the truncated absolute value of \f[B]x\f[R], as though it has \f[B]8\f[R] binary digits (\f[B]1\f[R] unsigned byte), by the number of places equal to the truncated absolute value of \f[B]p\f[R] modded by \f[B]2\f[R] to the power of \f[B]8\f[R]. .RS .PP If you want to a use signed two\[cq]s complement argument, use \f[B]s2u(x)\f[R] to convert. .RE .TP \f[B]brol16(x, p)\f[R] Does a left bitwise rotatation of the truncated absolute value of \f[B]x\f[R], as though it has \f[B]16\f[R] binary digits (\f[B]2\f[R] unsigned bytes), by the number of places equal to the truncated absolute value of \f[B]p\f[R] modded by \f[B]2\f[R] to the power of \f[B]16\f[R]. .RS .PP If you want to a use signed two\[cq]s complement argument, use \f[B]s2u(x)\f[R] to convert. .RE .TP \f[B]brol32(x, p)\f[R] Does a left bitwise rotatation of the truncated absolute value of \f[B]x\f[R], as though it has \f[B]32\f[R] binary digits (\f[B]2\f[R] unsigned bytes), by the number of places equal to the truncated absolute value of \f[B]p\f[R] modded by \f[B]2\f[R] to the power of \f[B]32\f[R]. .RS .PP If you want to a use signed two\[cq]s complement argument, use \f[B]s2u(x)\f[R] to convert. .RE .TP \f[B]brol64(x, p)\f[R] Does a left bitwise rotatation of the truncated absolute value of \f[B]x\f[R], as though it has \f[B]64\f[R] binary digits (\f[B]2\f[R] unsigned bytes), by the number of places equal to the truncated absolute value of \f[B]p\f[R] modded by \f[B]2\f[R] to the power of \f[B]64\f[R]. .RS .PP If you want to a use signed two\[cq]s complement argument, use \f[B]s2u(x)\f[R] to convert. .RE .TP \f[B]brol(x, p)\f[R] Does a left bitwise rotatation of the truncated absolute value of \f[B]x\f[R], as though it has the minimum number of power of two unsigned 8-bit bytes, by the number of places equal to the truncated absolute value of \f[B]p\f[R] modded by 2 to the power of the number of binary digits in the minimum number of 8-bit bytes. .RS .PP If you want to a use signed two\[cq]s complement argument, use \f[B]s2u(x)\f[R] to convert. .RE .TP \f[B]brorn(x, p, n)\f[R] Does a right bitwise rotatation of the truncated absolute value of \f[B]x\f[R], as though it has the same number of unsigned 8-bit bytes as the truncated absolute value of \f[B]n\f[R], by the number of places equal to the truncated absolute value of \f[B]p\f[R] modded by the \f[B]2\f[R] to the power of the number of binary digits in \f[B]n\f[R] 8-bit bytes. .RS .PP If you want to a use signed two\[cq]s complement argument, use \f[B]s2u(x)\f[R] to convert. .RE .TP \f[B]bror8(x, p)\f[R] Does a right bitwise rotatation of the truncated absolute value of \f[B]x\f[R], as though it has \f[B]8\f[R] binary digits (\f[B]1\f[R] unsigned byte), by the number of places equal to the truncated absolute value of \f[B]p\f[R] modded by \f[B]2\f[R] to the power of \f[B]8\f[R]. .RS .PP If you want to a use signed two\[cq]s complement argument, use \f[B]s2u(x)\f[R] to convert. .RE .TP \f[B]bror16(x, p)\f[R] Does a right bitwise rotatation of the truncated absolute value of \f[B]x\f[R], as though it has \f[B]16\f[R] binary digits (\f[B]2\f[R] unsigned bytes), by the number of places equal to the truncated absolute value of \f[B]p\f[R] modded by \f[B]2\f[R] to the power of \f[B]16\f[R]. .RS .PP If you want to a use signed two\[cq]s complement argument, use \f[B]s2u(x)\f[R] to convert. .RE .TP \f[B]bror32(x, p)\f[R] Does a right bitwise rotatation of the truncated absolute value of \f[B]x\f[R], as though it has \f[B]32\f[R] binary digits (\f[B]2\f[R] unsigned bytes), by the number of places equal to the truncated absolute value of \f[B]p\f[R] modded by \f[B]2\f[R] to the power of \f[B]32\f[R]. .RS .PP If you want to a use signed two\[cq]s complement argument, use \f[B]s2u(x)\f[R] to convert. .RE .TP \f[B]bror64(x, p)\f[R] Does a right bitwise rotatation of the truncated absolute value of \f[B]x\f[R], as though it has \f[B]64\f[R] binary digits (\f[B]2\f[R] unsigned bytes), by the number of places equal to the truncated absolute value of \f[B]p\f[R] modded by \f[B]2\f[R] to the power of \f[B]64\f[R]. .RS .PP If you want to a use signed two\[cq]s complement argument, use \f[B]s2u(x)\f[R] to convert. .RE .TP \f[B]bror(x, p)\f[R] Does a right bitwise rotatation of the truncated absolute value of \f[B]x\f[R], as though it has the minimum number of power of two unsigned 8-bit bytes, by the number of places equal to the truncated absolute value of \f[B]p\f[R] modded by 2 to the power of the number of binary digits in the minimum number of 8-bit bytes. .RS .PP If you want to a use signed two\[cq]s complement argument, use \f[B]s2u(x)\f[R] to convert. .RE .TP \f[B]bmodn(x, n)\f[R] Returns the modulus of the truncated absolute value of \f[B]x\f[R] by \f[B]2\f[R] to the power of the multiplication of the truncated absolute value of \f[B]n\f[R] and \f[B]8\f[R]. .RS .PP If you want to a use signed two\[cq]s complement argument, use \f[B]s2u(x)\f[R] to convert. .RE .TP \f[B]bmod8(x, n)\f[R] Returns the modulus of the truncated absolute value of \f[B]x\f[R] by \f[B]2\f[R] to the power of \f[B]8\f[R]. .RS .PP If you want to a use signed two\[cq]s complement argument, use \f[B]s2u(x)\f[R] to convert. .RE .TP \f[B]bmod16(x, n)\f[R] Returns the modulus of the truncated absolute value of \f[B]x\f[R] by \f[B]2\f[R] to the power of \f[B]16\f[R]. .RS .PP If you want to a use signed two\[cq]s complement argument, use \f[B]s2u(x)\f[R] to convert. .RE .TP \f[B]bmod32(x, n)\f[R] Returns the modulus of the truncated absolute value of \f[B]x\f[R] by \f[B]2\f[R] to the power of \f[B]32\f[R]. .RS .PP If you want to a use signed two\[cq]s complement argument, use \f[B]s2u(x)\f[R] to convert. .RE .TP \f[B]bmod64(x, n)\f[R] Returns the modulus of the truncated absolute value of \f[B]x\f[R] by \f[B]2\f[R] to the power of \f[B]64\f[R]. .RS .PP If you want to a use signed two\[cq]s complement argument, use \f[B]s2u(x)\f[R] to convert. .RE .TP \f[B]bunrev(t)\f[R] Assumes \f[B]t\f[R] is a bitwise-reversed number with an extra set bit one place more significant than the real most significant bit (which was the least significant bit in the original number). This number is reversed and returned without the extra set bit. .RS .PP This function is used to implement other bitwise functions; it is not meant to be used by users, but it can be. .RE .TP \f[B]plz(x)\f[R] If \f[B]x\f[R] is not equal to \f[B]0\f[R] and greater that \f[B]-1\f[R] and less than \f[B]1\f[R], it is printed with a leading zero, regardless of the use of the \f[B]-z\f[R] option (see the \f[B]OPTIONS\f[R] section) and without a trailing newline. .RS .PP Otherwise, \f[B]x\f[R] is printed normally, without a trailing newline. .RE .TP \f[B]plznl(x)\f[R] If \f[B]x\f[R] is not equal to \f[B]0\f[R] and greater that \f[B]-1\f[R] and less than \f[B]1\f[R], it is printed with a leading zero, regardless of the use of the \f[B]-z\f[R] option (see the \f[B]OPTIONS\f[R] section) and with a trailing newline. .RS .PP Otherwise, \f[B]x\f[R] is printed normally, with a trailing newline. .RE .TP \f[B]pnlz(x)\f[R] If \f[B]x\f[R] is not equal to \f[B]0\f[R] and greater that \f[B]-1\f[R] and less than \f[B]1\f[R], it is printed without a leading zero, regardless of the use of the \f[B]-z\f[R] option (see the \f[B]OPTIONS\f[R] section) and without a trailing newline. .RS .PP Otherwise, \f[B]x\f[R] is printed normally, without a trailing newline. .RE .TP \f[B]pnlznl(x)\f[R] If \f[B]x\f[R] is not equal to \f[B]0\f[R] and greater that \f[B]-1\f[R] and less than \f[B]1\f[R], it is printed without a leading zero, regardless of the use of the \f[B]-z\f[R] option (see the \f[B]OPTIONS\f[R] section) and with a trailing newline. .RS .PP Otherwise, \f[B]x\f[R] is printed normally, with a trailing newline. .RE .TP \f[B]ubytes(x)\f[R] Returns the numbers of unsigned integer bytes required to hold the truncated absolute value of \f[B]x\f[R]. .TP \f[B]sbytes(x)\f[R] Returns the numbers of signed, two\[cq]s-complement integer bytes required to hold the truncated value of \f[B]x\f[R]. .TP \f[B]s2u(x)\f[R] Returns \f[B]x\f[R] if it is non-negative. If it \f[I]is\f[R] negative, then it calculates what \f[B]x\f[R] would be as a 2\[cq]s-complement signed integer and returns the non-negative integer that would have the same representation in binary. .TP \f[B]s2un(x,n)\f[R] Returns \f[B]x\f[R] if it is non-negative. If it \f[I]is\f[R] negative, then it calculates what \f[B]x\f[R] would be as a 2\[cq]s-complement signed integer with \f[B]n\f[R] bytes and returns the non-negative integer that would have the same representation in binary. If \f[B]x\f[R] cannot fit into \f[B]n\f[R] 2\[cq]s-complement signed bytes, it is truncated to fit. .TP \f[B]hex(x)\f[R] Outputs the hexadecimal (base \f[B]16\f[R]) representation of \f[B]x\f[R]. .RS .PP This is a \f[B]void\f[R] function (see the \f[I]Void Functions\f[R] subsection of the \f[B]FUNCTIONS\f[R] section). .RE .TP \f[B]binary(x)\f[R] Outputs the binary (base \f[B]2\f[R]) representation of \f[B]x\f[R]. .RS .PP This is a \f[B]void\f[R] function (see the \f[I]Void Functions\f[R] subsection of the \f[B]FUNCTIONS\f[R] section). .RE .TP \f[B]output(x, b)\f[R] Outputs the base \f[B]b\f[R] representation of \f[B]x\f[R]. .RS .PP This is a \f[B]void\f[R] function (see the \f[I]Void Functions\f[R] subsection of the \f[B]FUNCTIONS\f[R] section). .RE .TP \f[B]uint(x)\f[R] Outputs the representation, in binary and hexadecimal, of \f[B]x\f[R] as an unsigned integer in as few power of two bytes as possible. Both outputs are split into bytes separated by spaces. .RS .PP If \f[B]x\f[R] is not an integer or is negative, an error message is printed instead, but bc(1) is not reset (see the \f[B]RESET\f[R] section). .PP This is a \f[B]void\f[R] function (see the \f[I]Void Functions\f[R] subsection of the \f[B]FUNCTIONS\f[R] section). .RE .TP \f[B]int(x)\f[R] Outputs the representation, in binary and hexadecimal, of \f[B]x\f[R] as a signed, two\[cq]s-complement integer in as few power of two bytes as possible. Both outputs are split into bytes separated by spaces. .RS .PP If \f[B]x\f[R] is not an integer, an error message is printed instead, but bc(1) is not reset (see the \f[B]RESET\f[R] section). .PP This is a \f[B]void\f[R] function (see the \f[I]Void Functions\f[R] subsection of the \f[B]FUNCTIONS\f[R] section). .RE .TP \f[B]uintn(x, n)\f[R] Outputs the representation, in binary and hexadecimal, of \f[B]x\f[R] as an unsigned integer in \f[B]n\f[R] bytes. Both outputs are split into bytes separated by spaces. .RS .PP If \f[B]x\f[R] is not an integer, is negative, or cannot fit into \f[B]n\f[R] bytes, an error message is printed instead, but bc(1) is not reset (see the \f[B]RESET\f[R] section). .PP This is a \f[B]void\f[R] function (see the \f[I]Void Functions\f[R] subsection of the \f[B]FUNCTIONS\f[R] section). .RE .TP \f[B]intn(x, n)\f[R] Outputs the representation, in binary and hexadecimal, of \f[B]x\f[R] as a signed, two\[cq]s-complement integer in \f[B]n\f[R] bytes. Both outputs are split into bytes separated by spaces. .RS .PP If \f[B]x\f[R] is not an integer or cannot fit into \f[B]n\f[R] bytes, an error message is printed instead, but bc(1) is not reset (see the \f[B]RESET\f[R] section). .PP This is a \f[B]void\f[R] function (see the \f[I]Void Functions\f[R] subsection of the \f[B]FUNCTIONS\f[R] section). .RE .TP \f[B]uint8(x)\f[R] Outputs the representation, in binary and hexadecimal, of \f[B]x\f[R] as an unsigned integer in \f[B]1\f[R] byte. Both outputs are split into bytes separated by spaces. .RS .PP If \f[B]x\f[R] is not an integer, is negative, or cannot fit into \f[B]1\f[R] byte, an error message is printed instead, but bc(1) is not reset (see the \f[B]RESET\f[R] section). .PP This is a \f[B]void\f[R] function (see the \f[I]Void Functions\f[R] subsection of the \f[B]FUNCTIONS\f[R] section). .RE .TP \f[B]int8(x)\f[R] Outputs the representation, in binary and hexadecimal, of \f[B]x\f[R] as a signed, two\[cq]s-complement integer in \f[B]1\f[R] byte. Both outputs are split into bytes separated by spaces. .RS .PP If \f[B]x\f[R] is not an integer or cannot fit into \f[B]1\f[R] byte, an error message is printed instead, but bc(1) is not reset (see the \f[B]RESET\f[R] section). .PP This is a \f[B]void\f[R] function (see the \f[I]Void Functions\f[R] subsection of the \f[B]FUNCTIONS\f[R] section). .RE .TP \f[B]uint16(x)\f[R] Outputs the representation, in binary and hexadecimal, of \f[B]x\f[R] as an unsigned integer in \f[B]2\f[R] bytes. Both outputs are split into bytes separated by spaces. .RS .PP If \f[B]x\f[R] is not an integer, is negative, or cannot fit into \f[B]2\f[R] bytes, an error message is printed instead, but bc(1) is not reset (see the \f[B]RESET\f[R] section). .PP This is a \f[B]void\f[R] function (see the \f[I]Void Functions\f[R] subsection of the \f[B]FUNCTIONS\f[R] section). .RE .TP \f[B]int16(x)\f[R] Outputs the representation, in binary and hexadecimal, of \f[B]x\f[R] as a signed, two\[cq]s-complement integer in \f[B]2\f[R] bytes. Both outputs are split into bytes separated by spaces. .RS .PP If \f[B]x\f[R] is not an integer or cannot fit into \f[B]2\f[R] bytes, an error message is printed instead, but bc(1) is not reset (see the \f[B]RESET\f[R] section). .PP This is a \f[B]void\f[R] function (see the \f[I]Void Functions\f[R] subsection of the \f[B]FUNCTIONS\f[R] section). .RE .TP \f[B]uint32(x)\f[R] Outputs the representation, in binary and hexadecimal, of \f[B]x\f[R] as an unsigned integer in \f[B]4\f[R] bytes. Both outputs are split into bytes separated by spaces. .RS .PP If \f[B]x\f[R] is not an integer, is negative, or cannot fit into \f[B]4\f[R] bytes, an error message is printed instead, but bc(1) is not reset (see the \f[B]RESET\f[R] section). .PP This is a \f[B]void\f[R] function (see the \f[I]Void Functions\f[R] subsection of the \f[B]FUNCTIONS\f[R] section). .RE .TP \f[B]int32(x)\f[R] Outputs the representation, in binary and hexadecimal, of \f[B]x\f[R] as a signed, two\[cq]s-complement integer in \f[B]4\f[R] bytes. Both outputs are split into bytes separated by spaces. .RS .PP If \f[B]x\f[R] is not an integer or cannot fit into \f[B]4\f[R] bytes, an error message is printed instead, but bc(1) is not reset (see the \f[B]RESET\f[R] section). .PP This is a \f[B]void\f[R] function (see the \f[I]Void Functions\f[R] subsection of the \f[B]FUNCTIONS\f[R] section). .RE .TP \f[B]uint64(x)\f[R] Outputs the representation, in binary and hexadecimal, of \f[B]x\f[R] as an unsigned integer in \f[B]8\f[R] bytes. Both outputs are split into bytes separated by spaces. .RS .PP If \f[B]x\f[R] is not an integer, is negative, or cannot fit into \f[B]8\f[R] bytes, an error message is printed instead, but bc(1) is not reset (see the \f[B]RESET\f[R] section). .PP This is a \f[B]void\f[R] function (see the \f[I]Void Functions\f[R] subsection of the \f[B]FUNCTIONS\f[R] section). .RE .TP \f[B]int64(x)\f[R] Outputs the representation, in binary and hexadecimal, of \f[B]x\f[R] as a signed, two\[cq]s-complement integer in \f[B]8\f[R] bytes. Both outputs are split into bytes separated by spaces. .RS .PP If \f[B]x\f[R] is not an integer or cannot fit into \f[B]8\f[R] bytes, an error message is printed instead, but bc(1) is not reset (see the \f[B]RESET\f[R] section). .PP This is a \f[B]void\f[R] function (see the \f[I]Void Functions\f[R] subsection of the \f[B]FUNCTIONS\f[R] section). .RE .TP \f[B]hex_uint(x, n)\f[R] Outputs the representation of the truncated absolute value of \f[B]x\f[R] as an unsigned integer in hexadecimal using \f[B]n\f[R] bytes. Not all of the value will be output if \f[B]n\f[R] is too small. .RS .PP This is a \f[B]void\f[R] function (see the \f[I]Void Functions\f[R] subsection of the \f[B]FUNCTIONS\f[R] section). .RE .TP \f[B]binary_uint(x, n)\f[R] Outputs the representation of the truncated absolute value of \f[B]x\f[R] as an unsigned integer in binary using \f[B]n\f[R] bytes. Not all of the value will be output if \f[B]n\f[R] is too small. .RS .PP This is a \f[B]void\f[R] function (see the \f[I]Void Functions\f[R] subsection of the \f[B]FUNCTIONS\f[R] section). .RE .TP \f[B]output_uint(x, n)\f[R] Outputs the representation of the truncated absolute value of \f[B]x\f[R] as an unsigned integer in the current \f[B]obase\f[R] (see the \f[B]SYNTAX\f[R] section) using \f[B]n\f[R] bytes. Not all of the value will be output if \f[B]n\f[R] is too small. .RS .PP This is a \f[B]void\f[R] function (see the \f[I]Void Functions\f[R] subsection of the \f[B]FUNCTIONS\f[R] section). .RE .TP \f[B]output_byte(x, i)\f[R] Outputs byte \f[B]i\f[R] of the truncated absolute value of \f[B]x\f[R], where \f[B]0\f[R] is the least significant byte and \f[B]number_of_bytes - 1\f[R] is the most significant byte. .RS .PP This is a \f[B]void\f[R] function (see the \f[I]Void Functions\f[R] subsection of the \f[B]FUNCTIONS\f[R] section). .RE .SS Transcendental Functions .PP All transcendental functions can return slightly inaccurate results (up to 1 ULP (https://en.wikipedia.org/wiki/Unit_in_the_last_place)). This is unavoidable, and this article (https://people.eecs.berkeley.edu/~wkahan/LOG10HAF.TXT) explains why it is impossible and unnecessary to calculate exact results for the transcendental functions. .PP Because of the possible inaccuracy, I recommend that users call those functions with the precision (\f[B]scale\f[R]) set to at least 1 higher than is necessary. If exact results are \f[I]absolutely\f[R] required, users can double the precision (\f[B]scale\f[R]) and then truncate. .PP The transcendental functions in the standard math library are: .IP \[bu] 2 \f[B]s(x)\f[R] .IP \[bu] 2 \f[B]c(x)\f[R] .IP \[bu] 2 \f[B]a(x)\f[R] .IP \[bu] 2 \f[B]l(x)\f[R] .IP \[bu] 2 \f[B]e(x)\f[R] .IP \[bu] 2 \f[B]j(x, n)\f[R] .PP The transcendental functions in the extended math library are: .IP \[bu] 2 \f[B]l2(x)\f[R] .IP \[bu] 2 \f[B]l10(x)\f[R] .IP \[bu] 2 \f[B]log(x, b)\f[R] .IP \[bu] 2 \f[B]pi(p)\f[R] .IP \[bu] 2 \f[B]t(x)\f[R] .IP \[bu] 2 \f[B]a2(y, x)\f[R] .IP \[bu] 2 \f[B]sin(x)\f[R] .IP \[bu] 2 \f[B]cos(x)\f[R] .IP \[bu] 2 \f[B]tan(x)\f[R] .IP \[bu] 2 \f[B]atan(x)\f[R] .IP \[bu] 2 \f[B]atan2(y, x)\f[R] .IP \[bu] 2 \f[B]r2d(x)\f[R] .IP \[bu] 2 \f[B]d2r(x)\f[R] .SH RESET .PP When bc(1) encounters an error or a signal that it has a non-default handler for, it resets. This means that several things happen. .PP First, any functions that are executing are stopped and popped off the stack. The behavior is not unlike that of exceptions in programming languages. Then the execution point is set so that any code waiting to execute (after all functions returned) is skipped. .PP Thus, when bc(1) resets, it skips any remaining code waiting to be executed. Then, if it is interactive mode, and the error was not a fatal error (see the \f[B]EXIT STATUS\f[R] section), it asks for more input; otherwise, it exits with the appropriate return code. .PP Note that this reset behavior is different from the GNU bc(1), which attempts to start executing the statement right after the one that caused an error. .SH PERFORMANCE .PP Most bc(1) implementations use \f[B]char\f[R] types to calculate the value of \f[B]1\f[R] decimal digit at a time, but that can be slow. This bc(1) does something different. .PP It uses large integers to calculate more than \f[B]1\f[R] decimal digit at a time. If built in a environment where \f[B]BC_LONG_BIT\f[R] (see the \f[B]LIMITS\f[R] section) is \f[B]64\f[R], then each integer has \f[B]9\f[R] decimal digits. If built in an environment where \f[B]BC_LONG_BIT\f[R] is \f[B]32\f[R] then each integer has \f[B]4\f[R] decimal digits. This value (the number of decimal digits per large integer) is called \f[B]BC_BASE_DIGS\f[R]. .PP The actual values of \f[B]BC_LONG_BIT\f[R] and \f[B]BC_BASE_DIGS\f[R] can be queried with the \f[B]limits\f[R] statement. .PP In addition, this bc(1) uses an even larger integer for overflow checking. This integer type depends on the value of \f[B]BC_LONG_BIT\f[R], but is always at least twice as large as the integer type used to store digits. .SH LIMITS .PP The following are the limits on bc(1): .TP \f[B]BC_LONG_BIT\f[R] The number of bits in the \f[B]long\f[R] type in the environment where bc(1) was built. This determines how many decimal digits can be stored in a single large integer (see the \f[B]PERFORMANCE\f[R] section). .TP \f[B]BC_BASE_DIGS\f[R] The number of decimal digits per large integer (see the \f[B]PERFORMANCE\f[R] section). Depends on \f[B]BC_LONG_BIT\f[R]. .TP \f[B]BC_BASE_POW\f[R] The max decimal number that each large integer can store (see \f[B]BC_BASE_DIGS\f[R]) plus \f[B]1\f[R]. Depends on \f[B]BC_BASE_DIGS\f[R]. .TP \f[B]BC_OVERFLOW_MAX\f[R] The max number that the overflow type (see the \f[B]PERFORMANCE\f[R] section) can hold. Depends on \f[B]BC_LONG_BIT\f[R]. .TP \f[B]BC_BASE_MAX\f[R] The maximum output base. Set at \f[B]BC_BASE_POW\f[R]. .TP \f[B]BC_DIM_MAX\f[R] The maximum size of arrays. Set at \f[B]SIZE_MAX-1\f[R]. .TP \f[B]BC_SCALE_MAX\f[R] The maximum \f[B]scale\f[R]. Set at \f[B]BC_OVERFLOW_MAX-1\f[R]. .TP \f[B]BC_STRING_MAX\f[R] The maximum length of strings. Set at \f[B]BC_OVERFLOW_MAX-1\f[R]. .TP \f[B]BC_NAME_MAX\f[R] The maximum length of identifiers. Set at \f[B]BC_OVERFLOW_MAX-1\f[R]. .TP \f[B]BC_NUM_MAX\f[R] The maximum length of a number (in decimal digits), which includes digits after the decimal point. Set at \f[B]BC_OVERFLOW_MAX-1\f[R]. .TP \f[B]BC_RAND_MAX\f[R] The maximum integer (inclusive) returned by the \f[B]rand()\f[R] operand. Set at \f[B]2\[ha]BC_LONG_BIT-1\f[R]. .TP Exponent The maximum allowable exponent (positive or negative). Set at \f[B]BC_OVERFLOW_MAX\f[R]. .TP Number of vars The maximum number of vars/arrays. Set at \f[B]SIZE_MAX-1\f[R]. .PP The actual values can be queried with the \f[B]limits\f[R] statement. .PP These limits are meant to be effectively non-existent; the limits are so large (at least on 64-bit machines) that there should not be any point at which they become a problem. In fact, memory should be exhausted before these limits should be hit. .SH ENVIRONMENT VARIABLES .PP bc(1) recognizes the following environment variables: .TP \f[B]POSIXLY_CORRECT\f[R] If this variable exists (no matter the contents), bc(1) behaves as if the \f[B]-s\f[R] option was given. .TP \f[B]BC_ENV_ARGS\f[R] This is another way to give command-line arguments to bc(1). They should be in the same format as all other command-line arguments. These are always processed first, so any files given in \f[B]BC_ENV_ARGS\f[R] will be processed before arguments and files given on the command-line. This gives the user the ability to set up \[lq]standard\[rq] options and files to be used at every invocation. The most useful thing for such files to contain would be useful functions that the user might want every time bc(1) runs. .RS .PP The code that parses \f[B]BC_ENV_ARGS\f[R] will correctly handle quoted arguments, but it does not understand escape sequences. For example, the string \f[B]\[lq]/home/gavin/some bc file.bc\[rq]\f[R] will be correctly parsed, but the string \f[B]\[lq]/home/gavin/some \[dq]bc\[dq] file.bc\[rq]\f[R] will include the backslashes. .PP The quote parsing will handle either kind of quotes, \f[B]\[cq]\f[R] or \f[B]\[lq]\f[R]. Thus, if you have a file with any number of single quotes in the name, you can use double quotes as the outside quotes, as in \f[B]\[lq]some `bc' file.bc\[rq]\f[R], and vice versa if you have a file with double quotes. However, handling a file with both kinds of quotes in \f[B]BC_ENV_ARGS\f[R] is not supported due to the complexity of the parsing, though such files are still supported on the command-line where the parsing is done by the shell. .RE .TP \f[B]BC_LINE_LENGTH\f[R] If this environment variable exists and contains an integer that is greater than \f[B]1\f[R] and is less than \f[B]UINT16_MAX\f[R] (\f[B]2\[ha]16-1\f[R]), bc(1) will output lines to that length, including the backslash (\f[B]\[rs]\f[R]). The default line length is \f[B]70\f[R]. .RS .PP The special value of \f[B]0\f[R] will disable line length checking and print numbers without regard to line length and without backslashes and newlines. .RE .TP \f[B]BC_BANNER\f[R] If this environment variable exists and contains an integer, then a non-zero value activates the copyright banner when bc(1) is in interactive mode, while zero deactivates it. .RS .PP If bc(1) is not in interactive mode (see the \f[B]INTERACTIVE MODE\f[R] section), then this environment variable has no effect because bc(1) does not print the banner when not in interactive mode. .PP This environment variable overrides the default, which can be queried with the \f[B]-h\f[R] or \f[B]--help\f[R] options. .RE .TP \f[B]BC_SIGINT_RESET\f[R] If bc(1) is not in interactive mode (see the \f[B]INTERACTIVE MODE\f[R] section), then this environment variable has no effect because bc(1) exits on \f[B]SIGINT\f[R] when not in interactive mode. .RS .PP However, when bc(1) is in interactive mode, then if this environment variable exists and contains an integer, a non-zero value makes bc(1) reset on \f[B]SIGINT\f[R], rather than exit, and zero makes bc(1) exit. If this environment variable exists and is \f[I]not\f[R] an integer, then bc(1) will exit on \f[B]SIGINT\f[R]. .PP This environment variable overrides the default, which can be queried with the \f[B]-h\f[R] or \f[B]--help\f[R] options. .RE .TP \f[B]BC_TTY_MODE\f[R] If TTY mode is \f[I]not\f[R] available (see the \f[B]TTY MODE\f[R] section), then this environment variable has no effect. .RS .PP However, when TTY mode is available, then if this environment variable exists and contains an integer, then a non-zero value makes bc(1) use TTY mode, and zero makes bc(1) not use TTY mode. .PP This environment variable overrides the default, which can be queried with the \f[B]-h\f[R] or \f[B]--help\f[R] options. .RE .TP \f[B]BC_PROMPT\f[R] If TTY mode is \f[I]not\f[R] available (see the \f[B]TTY MODE\f[R] section), then this environment variable has no effect. .RS .PP However, when TTY mode is available, then if this environment variable exists and contains an integer, a non-zero value makes bc(1) use a prompt, and zero or a non-integer makes bc(1) not use a prompt. If this environment variable does not exist and \f[B]BC_TTY_MODE\f[R] does, then the value of the \f[B]BC_TTY_MODE\f[R] environment variable is used. .PP This environment variable and the \f[B]BC_TTY_MODE\f[R] environment variable override the default, which can be queried with the \f[B]-h\f[R] or \f[B]--help\f[R] options. .RE +.TP +\f[B]BC_EXPR_EXIT\f[R] +If any expressions or expression files are given on the command-line +with \f[B]-e\f[R], \f[B]--expression\f[R], \f[B]-f\f[R], or +\f[B]--file\f[R], then if this environment variable exists and contains +an integer, a non-zero value makes bc(1) exit after executing the +expressions and expression files, and a non-zero value makes bc(1) not +exit. +.RS +.PP +This environment variable overrides the default, which can be queried +with the \f[B]-h\f[R] or \f[B]--help\f[R] options. +.RE .SH EXIT STATUS .PP bc(1) returns the following exit statuses: .TP \f[B]0\f[R] No error. .TP \f[B]1\f[R] A math error occurred. This follows standard practice of using \f[B]1\f[R] for expected errors, since math errors will happen in the process of normal execution. .RS .PP Math errors include divide by \f[B]0\f[R], taking the square root of a negative number, using a negative number as a bound for the pseudo-random number generator, attempting to convert a negative number to a hardware integer, overflow when converting a number to a hardware integer, overflow when calculating the size of a number, and attempting to use a non-integer where an integer is required. .PP Converting to a hardware integer happens for the second operand of the power (\f[B]\[ha]\f[R]), places (\f[B]\[at]\f[R]), left shift (\f[B]<<\f[R]), and right shift (\f[B]>>\f[R]) operators and their corresponding assignment operators. .RE .TP \f[B]2\f[R] A parse error occurred. .RS .PP Parse errors include unexpected \f[B]EOF\f[R], using an invalid character, failing to find the end of a string or comment, using a token where it is invalid, giving an invalid expression, giving an invalid print statement, giving an invalid function definition, attempting to assign to an expression that is not a named expression (see the \f[I]Named Expressions\f[R] subsection of the \f[B]SYNTAX\f[R] section), giving an invalid \f[B]auto\f[R] list, having a duplicate \f[B]auto\f[R]/function parameter, failing to find the end of a code block, attempting to return a value from a \f[B]void\f[R] function, attempting to use a variable as a reference, and using any extensions when the option \f[B]-s\f[R] or any equivalents were given. .RE .TP \f[B]3\f[R] A runtime error occurred. .RS .PP Runtime errors include assigning an invalid number to any global (\f[B]ibase\f[R], \f[B]obase\f[R], or \f[B]scale\f[R]), giving a bad expression to a \f[B]read()\f[R] call, calling \f[B]read()\f[R] inside of a \f[B]read()\f[R] call, type errors, passing the wrong number of arguments to functions, attempting to call an undefined function, and attempting to use a \f[B]void\f[R] function call as a value in an expression. .RE .TP \f[B]4\f[R] A fatal error occurred. .RS .PP Fatal errors include memory allocation errors, I/O errors, failing to open files, attempting to use files that do not have only ASCII characters (bc(1) only accepts ASCII characters), attempting to open a directory as a file, and giving invalid command-line options. .RE .PP The exit status \f[B]4\f[R] is special; when a fatal error occurs, bc(1) always exits and returns \f[B]4\f[R], no matter what mode bc(1) is in. .PP The other statuses will only be returned when bc(1) is not in interactive mode (see the \f[B]INTERACTIVE MODE\f[R] section), since bc(1) resets its state (see the \f[B]RESET\f[R] section) and accepts more input when one of those errors occurs in interactive mode. This is also the case when interactive mode is forced by the \f[B]-i\f[R] flag or \f[B]--interactive\f[R] option. .PP These exit statuses allow bc(1) to be used in shell scripting with error checking, and its normal behavior can be forced by using the \f[B]-i\f[R] flag or \f[B]--interactive\f[R] option. .SH INTERACTIVE MODE .PP Per the standard (https://pubs.opengroup.org/onlinepubs/9699919799/utilities/bc.html), bc(1) has an interactive mode and a non-interactive mode. Interactive mode is turned on automatically when both \f[B]stdin\f[R] and \f[B]stdout\f[R] are hooked to a terminal, but the \f[B]-i\f[R] flag and \f[B]--interactive\f[R] option can turn it on in other situations. .PP In interactive mode, bc(1) attempts to recover from errors (see the \f[B]RESET\f[R] section), and in normal execution, flushes \f[B]stdout\f[R] as soon as execution is done for the current input. bc(1) may also reset on \f[B]SIGINT\f[R] instead of exit, depending on the contents of, or default for, the \f[B]BC_SIGINT_RESET\f[R] environment variable (see the \f[B]ENVIRONMENT VARIABLES\f[R] section). .SH TTY MODE .PP If \f[B]stdin\f[R], \f[B]stdout\f[R], and \f[B]stderr\f[R] are all connected to a TTY, then \[lq]TTY mode\[rq] is considered to be available, and thus, bc(1) can turn on TTY mode, subject to some settings. .PP If there is the environment variable \f[B]BC_TTY_MODE\f[R] in the environment (see the \f[B]ENVIRONMENT VARIABLES\f[R] section), then if that environment variable contains a non-zero integer, bc(1) will turn on TTY mode when \f[B]stdin\f[R], \f[B]stdout\f[R], and \f[B]stderr\f[R] are all connected to a TTY. If the \f[B]BC_TTY_MODE\f[R] environment variable exists but is \f[I]not\f[R] a non-zero integer, then bc(1) will not turn TTY mode on. .PP If the environment variable \f[B]BC_TTY_MODE\f[R] does \f[I]not\f[R] exist, the default setting is used. The default setting can be queried with the \f[B]-h\f[R] or \f[B]--help\f[R] options. .PP TTY mode is different from interactive mode because interactive mode is required in the bc(1) specification (https://pubs.opengroup.org/onlinepubs/9699919799/utilities/bc.html), and interactive mode requires only \f[B]stdin\f[R] and \f[B]stdout\f[R] to be connected to a terminal. .SS Command-Line History .PP Command-line history is only enabled if TTY mode is, i.e., that \f[B]stdin\f[R], \f[B]stdout\f[R], and \f[B]stderr\f[R] are connected to a TTY and the \f[B]BC_TTY_MODE\f[R] environment variable (see the \f[B]ENVIRONMENT VARIABLES\f[R] section) and its default do not disable TTY mode. See the \f[B]COMMAND LINE HISTORY\f[R] section for more information. .SS Prompt .PP If TTY mode is available, then a prompt can be enabled. Like TTY mode itself, it can be turned on or off with an environment variable: \f[B]BC_PROMPT\f[R] (see the \f[B]ENVIRONMENT VARIABLES\f[R] section). .PP If the environment variable \f[B]BC_PROMPT\f[R] exists and is a non-zero integer, then the prompt is turned on when \f[B]stdin\f[R], \f[B]stdout\f[R], and \f[B]stderr\f[R] are connected to a TTY and the \f[B]-P\f[R] and \f[B]--no-prompt\f[R] options were not used. The read prompt will be turned on under the same conditions, except that the \f[B]-R\f[R] and \f[B]--no-read-prompt\f[R] options must also not be used. .PP However, if \f[B]BC_PROMPT\f[R] does not exist, the prompt can be enabled or disabled with the \f[B]BC_TTY_MODE\f[R] environment variable, the \f[B]-P\f[R] and \f[B]--no-prompt\f[R] options, and the \f[B]-R\f[R] and \f[B]--no-read-prompt\f[R] options. See the \f[B]ENVIRONMENT VARIABLES\f[R] and \f[B]OPTIONS\f[R] sections for more details. .SH SIGNAL HANDLING .PP Sending a \f[B]SIGINT\f[R] will cause bc(1) to do one of two things. .PP If bc(1) is not in interactive mode (see the \f[B]INTERACTIVE MODE\f[R] section), or the \f[B]BC_SIGINT_RESET\f[R] environment variable (see the \f[B]ENVIRONMENT VARIABLES\f[R] section), or its default, is either not an integer or it is zero, bc(1) will exit. .PP However, if bc(1) is in interactive mode, and the \f[B]BC_SIGINT_RESET\f[R] or its default is an integer and non-zero, then bc(1) will stop executing the current input and reset (see the \f[B]RESET\f[R] section) upon receiving a \f[B]SIGINT\f[R]. .PP Note that \[lq]current input\[rq] can mean one of two things. If bc(1) is processing input from \f[B]stdin\f[R] in interactive mode, it will ask for more input. If bc(1) is processing input from a file in interactive mode, it will stop processing the file and start processing the next file, if one exists, or ask for input from \f[B]stdin\f[R] if no other file exists. .PP This means that if a \f[B]SIGINT\f[R] is sent to bc(1) as it is executing a file, it can seem as though bc(1) did not respond to the signal since it will immediately start executing the next file. This is by design; most files that users execute when interacting with bc(1) have function definitions, which are quick to parse. If a file takes a long time to execute, there may be a bug in that file. The rest of the files could still be executed without problem, allowing the user to continue. .PP \f[B]SIGTERM\f[R] and \f[B]SIGQUIT\f[R] cause bc(1) to clean up and exit, and it uses the default handler for all other signals. The one exception is \f[B]SIGHUP\f[R]; in that case, and only when bc(1) is in TTY mode (see the \f[B]TTY MODE\f[R] section), a \f[B]SIGHUP\f[R] will cause bc(1) to clean up and exit. .SH COMMAND LINE HISTORY .PP bc(1) supports interactive command-line editing. .PP If bc(1) can be in TTY mode (see the \f[B]TTY MODE\f[R] section), history can be enabled. This means that command-line history can only be enabled when \f[B]stdin\f[R], \f[B]stdout\f[R], and \f[B]stderr\f[R] are all connected to a TTY. .PP Like TTY mode itself, it can be turned on or off with the environment variable \f[B]BC_TTY_MODE\f[R] (see the \f[B]ENVIRONMENT VARIABLES\f[R] section). .PP If history is enabled, previous lines can be recalled and edited with the arrow keys. .PP \f[B]Note\f[R]: tabs are converted to 8 spaces. .SH SEE ALSO .PP dc(1) .SH STANDARDS .PP bc(1) is compliant with the IEEE Std 1003.1-2017 (\[lq]POSIX.1-2017\[rq]) (https://pubs.opengroup.org/onlinepubs/9699919799/utilities/bc.html) specification. The flags \f[B]-efghiqsvVw\f[R], all long options, and the extensions noted above are extensions to that specification. .PP Note that the specification explicitly says that bc(1) only accepts numbers that use a period (\f[B].\f[R]) as a radix point, regardless of the value of \f[B]LC_NUMERIC\f[R]. .SH BUGS .PP None are known. Report bugs at https://git.yzena.com/gavin/bc. .SH AUTHORS .PP Gavin D. Howard and contributors. diff --git a/contrib/bc/manuals/bc/N.1.md b/contrib/bc/manuals/bc/N.1.md index 51dad376b56d..92c239c0b12b 100644 --- a/contrib/bc/manuals/bc/N.1.md +++ b/contrib/bc/manuals/bc/N.1.md @@ -1,2339 +1,2350 @@ # NAME bc - arbitrary-precision decimal arithmetic language and calculator # SYNOPSIS **bc** [**-ghilPqRsvVw**] [**-\-global-stacks**] [**-\-help**] [**-\-interactive**] [**-\-mathlib**] [**-\-no-prompt**] [**-\-no-read-prompt**] [**-\-quiet**] [**-\-standard**] [**-\-warn**] [**-\-version**] [**-e** *expr*] [**-\-expression**=*expr*...] [**-f** *file*...] [**-\-file**=*file*...] [*file*...] # DESCRIPTION bc(1) is an interactive processor for a language first standardized in 1991 by POSIX. (The current standard is [here][1].) The language provides unlimited precision decimal arithmetic and is somewhat C-like, but there are differences. Such differences will be noted in this document. After parsing and handling options, this bc(1) reads any files given on the command line and executes them before reading from **stdin**. This bc(1) is a drop-in replacement for *any* bc(1), including (and especially) the GNU bc(1). It also has many extensions and extra features beyond other implementations. **Note**: If running this bc(1) on *any* script meant for another bc(1) gives a parse error, it is probably because a word this bc(1) reserves as a keyword is used as the name of a function, variable, or array. To fix that, use the command-line option **-r** *keyword*, where *keyword* is the keyword that is used as a name in the script. For more information, see the **OPTIONS** section. If parsing scripts meant for other bc(1) implementations still does not work, that is a bug and should be reported. See the **BUGS** section. # OPTIONS The following are the options that bc(1) accepts. **-g**, **-\-global-stacks** : Turns the globals **ibase**, **obase**, **scale**, and **seed** into stacks. This has the effect that a copy of the current value of all four are pushed onto a stack for every function call, as well as popped when every function returns. This means that functions can assign to any and all of those globals without worrying that the change will affect other functions. Thus, a hypothetical function named **output(x,b)** that simply printed **x** in base **b** could be written like this: define void output(x, b) { obase=b x } instead of like this: define void output(x, b) { auto c c=obase obase=b x obase=c } This makes writing functions much easier. (**Note**: the function **output(x,b)** exists in the extended math library. See the **LIBRARY** section.) However, since using this flag means that functions cannot set **ibase**, **obase**, **scale**, or **seed** globally, functions that are made to do so cannot work anymore. There are two possible use cases for that, and each has a solution. First, if a function is called on startup to turn bc(1) into a number converter, it is possible to replace that capability with various shell aliases. Examples: alias d2o="bc -e ibase=A -e obase=8" alias h2b="bc -e ibase=G -e obase=2" Second, if the purpose of a function is to set **ibase**, **obase**, **scale**, or **seed** globally for any other purpose, it could be split into one to four functions (based on how many globals it sets) and each of those functions could return the desired value for a global. For functions that set **seed**, the value assigned to **seed** is not propagated to parent functions. This means that the sequence of pseudo-random numbers that they see will not be the same sequence of pseudo-random numbers that any parent sees. This is only the case once **seed** has been set. If a function desires to not affect the sequence of pseudo-random numbers of its parents, but wants to use the same **seed**, it can use the following line: seed = seed If the behavior of this option is desired for every run of bc(1), then users could make sure to define **BC_ENV_ARGS** and include this option (see the **ENVIRONMENT VARIABLES** section for more details). If **-s**, **-w**, or any equivalents are used, this option is ignored. This is a **non-portable extension**. **-h**, **-\-help** : Prints a usage message and quits. **-i**, **-\-interactive** : Forces interactive mode. (See the **INTERACTIVE MODE** section.) This is a **non-portable extension**. **-L**, **-\-no-line-length** : Disables line length checking and prints numbers without backslashes and newlines. In other words, this option sets **BC_LINE_LENGTH** to **0** (see the **ENVIRONMENT VARIABLES** section). This is a **non-portable extension**. **-l**, **-\-mathlib** : Sets **scale** (see the **SYNTAX** section) to **20** and loads the included math library and the extended math library before running any code, including any expressions or files specified on the command line. To learn what is in the libraries, see the **LIBRARY** section. **-P**, **-\-no-prompt** : Disables the prompt in TTY mode. (The prompt is only enabled in TTY mode. See the **TTY MODE** section.) This is mostly for those users that do not want a prompt or are not used to having them in bc(1). Most of those users would want to put this option in **BC_ENV_ARGS** (see the **ENVIRONMENT VARIABLES** section). These options override the **BC_PROMPT** and **BC_TTY_MODE** environment variables (see the **ENVIRONMENT VARIABLES** section). This is a **non-portable extension**. **-R**, **-\-no-read-prompt** : Disables the read prompt in TTY mode. (The read prompt is only enabled in TTY mode. See the **TTY MODE** section.) This is mostly for those users that do not want a read prompt or are not used to having them in bc(1). Most of those users would want to put this option in **BC_ENV_ARGS** (see the **ENVIRONMENT VARIABLES** section). This option is also useful in hash bang lines of bc(1) scripts that prompt for user input. This option does not disable the regular prompt because the read prompt is only used when the **read()** built-in function is called. These options *do* override the **BC_PROMPT** and **BC_TTY_MODE** environment variables (see the **ENVIRONMENT VARIABLES** section), but only for the read prompt. This is a **non-portable extension**. **-r** *keyword*, **-\-redefine**=*keyword* : Redefines *keyword* in order to allow it to be used as a function, variable, or array name. This is useful when this bc(1) gives parse errors when parsing scripts meant for other bc(1) implementations. The keywords this bc(1) allows to be redefined are: * **abs** * **asciify** * **continue** * **divmod** * **else** * **halt** * **irand** * **last** * **limits** * **maxibase** * **maxobase** * **maxrand** * **maxscale** * **modexp** * **print** * **rand** * **read** * **seed** * **stream** If any of those keywords are used as a function, variable, or array name in a script, use this option with the keyword as the argument. If multiple are used, use this option for all of them; it can be used multiple times. Keywords are *not* redefined when parsing the builtin math library (see the **LIBRARY** section). It is a fatal error to redefine keywords mandated by the POSIX standard. It is a fatal error to attempt to redefine words that this bc(1) does not reserve as keywords. **-q**, **-\-quiet** : This option is for compatibility with the [GNU bc(1)][2]; it is a no-op. Without this option, GNU bc(1) prints a copyright header. This bc(1) only prints the copyright header if one or more of the **-v**, **-V**, or **-\-version** options are given. This is a **non-portable extension**. **-s**, **-\-standard** : Process exactly the language defined by the [standard][1] and error if any extensions are used. This is a **non-portable extension**. **-v**, **-V**, **-\-version** : Print the version information (copyright header) and exit. This is a **non-portable extension**. **-w**, **-\-warn** : Like **-s** and **-\-standard**, except that warnings (and not errors) are printed for non-standard extensions and execution continues normally. This is a **non-portable extension**. **-z**, **-\-leading-zeroes** : Makes bc(1) print all numbers greater than **-1** and less than **1**, and not equal to **0**, with a leading zero. This can be set for individual numbers with the **plz(x)**, plznl(x)**, **pnlz(x)**, and **pnlznl(x)** functions in the extended math library (see the **LIBRARY** section). This is a **non-portable extension**. **-e** *expr*, **-\-expression**=*expr* : Evaluates *expr*. If multiple expressions are given, they are evaluated in order. If files are given as well (see below), the expressions and files are evaluated in the order given. This means that if a file is given before an expression, the file is read in and evaluated first. If this option is given on the command-line (i.e., not in **BC_ENV_ARGS**, see the **ENVIRONMENT VARIABLES** section), then after processing all expressions and files, bc(1) will exit, unless **-** (**stdin**) was given as an argument at least once to **-f** or **-\-file**, whether on the command-line or in **BC_ENV_ARGS**. However, if any other **-e**, **-\-expression**, **-f**, or **-\-file** arguments are given after **-f-** or equivalent is given, bc(1) will give a fatal error and exit. This is a **non-portable extension**. **-f** *file*, **-\-file**=*file* : Reads in *file* and evaluates it, line by line, as though it were read through **stdin**. If expressions are also given (see above), the expressions are evaluated in the order given. If this option is given on the command-line (i.e., not in **BC_ENV_ARGS**, see the **ENVIRONMENT VARIABLES** section), then after processing all expressions and files, bc(1) will exit, unless **-** (**stdin**) was given as an argument at least once to **-f** or **-\-file**. However, if any other **-e**, **-\-expression**, **-f**, or **-\-file** arguments are given after **-f-** or equivalent is given, bc(1) will give a fatal error and exit. This is a **non-portable extension**. All long options are **non-portable extensions**. # STDIN If no files or expressions are given by the **-f**, **-\-file**, **-e**, or **-\-expression** options, then bc(1) read from **stdin**. However, there are a few caveats to this. First, **stdin** is evaluated a line at a time. The only exception to this is if the parse cannot complete. That means that starting a string without ending it or starting a function, **if** statement, or loop without ending it will also cause bc(1) to not execute. Second, after an **if** statement, bc(1) doesn't know if an **else** statement will follow, so it will not execute until it knows there will not be an **else** statement. # STDOUT Any non-error output is written to **stdout**. In addition, if history (see the **HISTORY** section) and the prompt (see the **TTY MODE** section) are enabled, both are output to **stdout**. **Note**: Unlike other bc(1) implementations, this bc(1) will issue a fatal error (see the **EXIT STATUS** section) if it cannot write to **stdout**, so if **stdout** is closed, as in **bc >&-**, it will quit with an error. This is done so that bc(1) can report problems when **stdout** is redirected to a file. If there are scripts that depend on the behavior of other bc(1) implementations, it is recommended that those scripts be changed to redirect **stdout** to **/dev/null**. # STDERR Any error output is written to **stderr**. **Note**: Unlike other bc(1) implementations, this bc(1) will issue a fatal error (see the **EXIT STATUS** section) if it cannot write to **stderr**, so if **stderr** is closed, as in **bc 2>&-**, it will quit with an error. This is done so that bc(1) can exit with an error code when **stderr** is redirected to a file. If there are scripts that depend on the behavior of other bc(1) implementations, it is recommended that those scripts be changed to redirect **stderr** to **/dev/null**. # SYNTAX The syntax for bc(1) programs is mostly C-like, with some differences. This bc(1) follows the [POSIX standard][1], which is a much more thorough resource for the language this bc(1) accepts. This section is meant to be a summary and a listing of all the extensions to the standard. In the sections below, **E** means expression, **S** means statement, and **I** means identifier. Identifiers (**I**) start with a lowercase letter and can be followed by any number (up to **BC_NAME_MAX-1**) of lowercase letters (**a-z**), digits (**0-9**), and underscores (**\_**). The regex is **\[a-z\]\[a-z0-9\_\]\***. Identifiers with more than one character (letter) are a **non-portable extension**. **ibase** is a global variable determining how to interpret constant numbers. It is the "input" base, or the number base used for interpreting input numbers. **ibase** is initially **10**. If the **-s** (**-\-standard**) and **-w** (**-\-warn**) flags were not given on the command line, the max allowable value for **ibase** is **36**. Otherwise, it is **16**. The min allowable value for **ibase** is **2**. The max allowable value for **ibase** can be queried in bc(1) programs with the **maxibase()** built-in function. **obase** is a global variable determining how to output results. It is the "output" base, or the number base used for outputting numbers. **obase** is initially **10**. The max allowable value for **obase** is **BC_BASE_MAX** and can be queried in bc(1) programs with the **maxobase()** built-in function. The min allowable value for **obase** is **0**. If **obase** is **0**, values are output in scientific notation, and if **obase** is **1**, values are output in engineering notation. Otherwise, values are output in the specified base. Outputting in scientific and engineering notations are **non-portable extensions**. The *scale* of an expression is the number of digits in the result of the expression right of the decimal point, and **scale** is a global variable that sets the precision of any operations, with exceptions. **scale** is initially **0**. **scale** cannot be negative. The max allowable value for **scale** is **BC_SCALE_MAX** and can be queried in bc(1) programs with the **maxscale()** built-in function. bc(1) has both *global* variables and *local* variables. All *local* variables are local to the function; they are parameters or are introduced in the **auto** list of a function (see the **FUNCTIONS** section). If a variable is accessed which is not a parameter or in the **auto** list, it is assumed to be *global*. If a parent function has a *local* variable version of a variable that a child function considers *global*, the value of that *global* variable in the child function is the value of the variable in the parent function, not the value of the actual *global* variable. All of the above applies to arrays as well. The value of a statement that is an expression (i.e., any of the named expressions or operands) is printed unless the lowest precedence operator is an assignment operator *and* the expression is notsurrounded by parentheses. The value that is printed is also assigned to the special variable **last**. A single dot (**.**) may also be used as a synonym for **last**. These are **non-portable extensions**. Either semicolons or newlines may separate statements. ## Comments There are two kinds of comments: 1. Block comments are enclosed in **/\*** and **\*/**. 2. Line comments go from **#** until, and not including, the next newline. This is a **non-portable extension**. ## Named Expressions The following are named expressions in bc(1): 1. Variables: **I** 2. Array Elements: **I[E]** 3. **ibase** 4. **obase** 5. **scale** 6. **seed** 7. **last** or a single dot (**.**) Numbers 6 and 7 are **non-portable extensions**. The meaning of **seed** is dependent on the current pseudo-random number generator but is guaranteed to not change except for new major versions. The *scale* and sign of the value may be significant. If a previously used **seed** value is assigned to **seed** and used again, the pseudo-random number generator is guaranteed to produce the same sequence of pseudo-random numbers as it did when the **seed** value was previously used. The exact value assigned to **seed** is not guaranteed to be returned if **seed** is queried again immediately. However, if **seed** *does* return a different value, both values, when assigned to **seed**, are guaranteed to produce the same sequence of pseudo-random numbers. This means that certain values assigned to **seed** will *not* produce unique sequences of pseudo-random numbers. The value of **seed** will change after any use of the **rand()** and **irand(E)** operands (see the *Operands* subsection below), except if the parameter passed to **irand(E)** is **0**, **1**, or negative. There is no limit to the length (number of significant decimal digits) or *scale* of the value that can be assigned to **seed**. Variables and arrays do not interfere; users can have arrays named the same as variables. This also applies to functions (see the **FUNCTIONS** section), so a user can have a variable, array, and function that all have the same name, and they will not shadow each other, whether inside of functions or not. Named expressions are required as the operand of **increment**/**decrement** operators and as the left side of **assignment** operators (see the *Operators* subsection). ## Operands The following are valid operands in bc(1): 1. Numbers (see the *Numbers* subsection below). 2. Array indices (**I[E]**). 3. **(E)**: The value of **E** (used to change precedence). 4. **sqrt(E)**: The square root of **E**. **E** must be non-negative. 5. **length(E)**: The number of significant decimal digits in **E**. Returns **1** for **0** with no decimal places. If given a string, the length of the string is returned. Passing a string to **length(E)** is a **non-portable extension**. 6. **length(I[])**: The number of elements in the array **I**. This is a **non-portable extension**. 7. **scale(E)**: The *scale* of **E**. 8. **abs(E)**: The absolute value of **E**. This is a **non-portable extension**. 9. **modexp(E, E, E)**: Modular exponentiation, where the first expression is the base, the second is the exponent, and the third is the modulus. All three values must be integers. The second argument must be non-negative. The third argument must be non-zero. This is a **non-portable extension**. 10. **divmod(E, E, I[])**: Division and modulus in one operation. This is for optimization. The first expression is the dividend, and the second is the divisor, which must be non-zero. The return value is the quotient, and the modulus is stored in index **0** of the provided array (the last argument). This is a **non-portable extension**. 11. **asciify(E)**: If **E** is a string, returns a string that is the first letter of its argument. If it is a number, calculates the number mod **256** and returns that number as a one-character string. This is a **non-portable extension**. 12. **I()**, **I(E)**, **I(E, E)**, and so on, where **I** is an identifier for a non-**void** function (see the *Void Functions* subsection of the **FUNCTIONS** section). The **E** argument(s) may also be arrays of the form **I[]**, which will automatically be turned into array references (see the *Array References* subsection of the **FUNCTIONS** section) if the corresponding parameter in the function definition is an array reference. 13. **read()**: Reads a line from **stdin** and uses that as an expression. The result of that expression is the result of the **read()** operand. This is a **non-portable extension**. 14. **maxibase()**: The max allowable **ibase**. This is a **non-portable extension**. 15. **maxobase()**: The max allowable **obase**. This is a **non-portable extension**. 16. **maxscale()**: The max allowable **scale**. This is a **non-portable extension**. 17. **line_length()**: The line length set with **BC_LINE_LENGTH** (see the **ENVIRONMENT VARIABLES** section). This is a **non-portable extension**. 18. **global_stacks()**: **0** if global stacks are not enabled with the **-g** or **-\-global-stacks** options, non-zero otherwise. See the **OPTIONS** section. This is a **non-portable extension**. 19. **leading_zero()**: **0** if leading zeroes are not enabled with the **-z** or **--leading-zeroes** options, non-zero otherwise. See the **OPTIONS** section. This is a **non-portable extension**. 20. **rand()**: A pseudo-random integer between **0** (inclusive) and **BC_RAND_MAX** (inclusive). Using this operand will change the value of **seed**. This is a **non-portable extension**. 21. **irand(E)**: A pseudo-random integer between **0** (inclusive) and the value of **E** (exclusive). If **E** is negative or is a non-integer (**E**'s *scale* is not **0**), an error is raised, and bc(1) resets (see the **RESET** section) while **seed** remains unchanged. If **E** is larger than **BC_RAND_MAX**, the higher bound is honored by generating several pseudo-random integers, multiplying them by appropriate powers of **BC_RAND_MAX+1**, and adding them together. Thus, the size of integer that can be generated with this operand is unbounded. Using this operand will change the value of **seed**, unless the value of **E** is **0** or **1**. In that case, **0** is returned, and **seed** is *not* changed. This is a **non-portable extension**. 22. **maxrand()**: The max integer returned by **rand()**. This is a **non-portable extension**. The integers generated by **rand()** and **irand(E)** are guaranteed to be as unbiased as possible, subject to the limitations of the pseudo-random number generator. **Note**: The values returned by the pseudo-random number generator with **rand()** and **irand(E)** are guaranteed to *NOT* be cryptographically secure. This is a consequence of using a seeded pseudo-random number generator. However, they *are* guaranteed to be reproducible with identical **seed** values. This means that the pseudo-random values from bc(1) should only be used where a reproducible stream of pseudo-random numbers is *ESSENTIAL*. In any other case, use a non-seeded pseudo-random number generator. ## Numbers Numbers are strings made up of digits, uppercase letters, and at most **1** period for a radix. Numbers can have up to **BC_NUM_MAX** digits. Uppercase letters are equal to **9** + their position in the alphabet (i.e., **A** equals **10**, or **9+1**). If a digit or letter makes no sense with the current value of **ibase**, they are set to the value of the highest valid digit in **ibase**. Single-character numbers (i.e., **A** alone) take the value that they would have if they were valid digits, regardless of the value of **ibase**. This means that **A** alone always equals decimal **10** and **Z** alone always equals decimal **35**. In addition, bc(1) accepts numbers in scientific notation. These have the form **\e\**. The exponent (the portion after the **e**) must be an integer. An example is **1.89237e9**, which is equal to **1892370000**. Negative exponents are also allowed, so **4.2890e-3** is equal to **0.0042890**. Using scientific notation is an error or warning if the **-s** or **-w**, respectively, command-line options (or equivalents) are given. **WARNING**: Both the number and the exponent in scientific notation are interpreted according to the current **ibase**, but the number is still multiplied by **10\^exponent** regardless of the current **ibase**. For example, if **ibase** is **16** and bc(1) is given the number string **FFeA**, the resulting decimal number will be **2550000000000**, and if bc(1) is given the number string **10e-4**, the resulting decimal number will be **0.0016**. Accepting input as scientific notation is a **non-portable extension**. ## Operators The following arithmetic and logical operators can be used. They are listed in order of decreasing precedence. Operators in the same group have the same precedence. **++** **-\-** : Type: Prefix and Postfix Associativity: None Description: **increment**, **decrement** **-** **!** : Type: Prefix Associativity: None Description: **negation**, **boolean not** **\$** : Type: Postfix Associativity: None Description: **truncation** **\@** : Type: Binary Associativity: Right Description: **set precision** **\^** : Type: Binary Associativity: Right Description: **power** **\*** **/** **%** : Type: Binary Associativity: Left Description: **multiply**, **divide**, **modulus** **+** **-** : Type: Binary Associativity: Left Description: **add**, **subtract** **\<\<** **\>\>** : Type: Binary Associativity: Left Description: **shift left**, **shift right** **=** **\<\<=** **\>\>=** **+=** **-=** **\*=** **/=** **%=** **\^=** **\@=** : Type: Binary Associativity: Right Description: **assignment** **==** **\<=** **\>=** **!=** **\<** **\>** : Type: Binary Associativity: Left Description: **relational** **&&** : Type: Binary Associativity: Left Description: **boolean and** **||** : Type: Binary Associativity: Left Description: **boolean or** The operators will be described in more detail below. **++** **-\-** : The prefix and postfix **increment** and **decrement** operators behave exactly like they would in C. They require a named expression (see the *Named Expressions* subsection) as an operand. The prefix versions of these operators are more efficient; use them where possible. **-** : The **negation** operator returns **0** if a user attempts to negate any expression with the value **0**. Otherwise, a copy of the expression with its sign flipped is returned. **!** : The **boolean not** operator returns **1** if the expression is **0**, or **0** otherwise. This is a **non-portable extension**. **\$** : The **truncation** operator returns a copy of the given expression with all of its *scale* removed. This is a **non-portable extension**. **\@** : The **set precision** operator takes two expressions and returns a copy of the first with its *scale* equal to the value of the second expression. That could either mean that the number is returned without change (if the *scale* of the first expression matches the value of the second expression), extended (if it is less), or truncated (if it is more). The second expression must be an integer (no *scale*) and non-negative. This is a **non-portable extension**. **\^** : The **power** operator (not the **exclusive or** operator, as it would be in C) takes two expressions and raises the first to the power of the value of the second. The *scale* of the result is equal to **scale**. The second expression must be an integer (no *scale*), and if it is negative, the first value must be non-zero. **\*** : The **multiply** operator takes two expressions, multiplies them, and returns the product. If **a** is the *scale* of the first expression and **b** is the *scale* of the second expression, the *scale* of the result is equal to **min(a+b,max(scale,a,b))** where **min()** and **max()** return the obvious values. **/** : The **divide** operator takes two expressions, divides them, and returns the quotient. The *scale* of the result shall be the value of **scale**. The second expression must be non-zero. **%** : The **modulus** operator takes two expressions, **a** and **b**, and evaluates them by 1) Computing **a/b** to current **scale** and 2) Using the result of step 1 to calculate **a-(a/b)\*b** to *scale* **max(scale+scale(b),scale(a))**. The second expression must be non-zero. **+** : The **add** operator takes two expressions, **a** and **b**, and returns the sum, with a *scale* equal to the max of the *scale*s of **a** and **b**. **-** : The **subtract** operator takes two expressions, **a** and **b**, and returns the difference, with a *scale* equal to the max of the *scale*s of **a** and **b**. **\<\<** : The **left shift** operator takes two expressions, **a** and **b**, and returns a copy of the value of **a** with its decimal point moved **b** places to the right. The second expression must be an integer (no *scale*) and non-negative. This is a **non-portable extension**. **\>\>** : The **right shift** operator takes two expressions, **a** and **b**, and returns a copy of the value of **a** with its decimal point moved **b** places to the left. The second expression must be an integer (no *scale*) and non-negative. This is a **non-portable extension**. **=** **\<\<=** **\>\>=** **+=** **-=** **\*=** **/=** **%=** **\^=** **\@=** : The **assignment** operators take two expressions, **a** and **b** where **a** is a named expression (see the *Named Expressions* subsection). For **=**, **b** is copied and the result is assigned to **a**. For all others, **a** and **b** are applied as operands to the corresponding arithmetic operator and the result is assigned to **a**. The **assignment** operators that correspond to operators that are extensions are themselves **non-portable extensions**. **==** **\<=** **\>=** **!=** **\<** **\>** : The **relational** operators compare two expressions, **a** and **b**, and if the relation holds, according to C language semantics, the result is **1**. Otherwise, it is **0**. Note that unlike in C, these operators have a lower precedence than the **assignment** operators, which means that **a=b\>c** is interpreted as **(a=b)\>c**. Also, unlike the [standard][1] requires, these operators can appear anywhere any other expressions can be used. This allowance is a **non-portable extension**. **&&** : The **boolean and** operator takes two expressions and returns **1** if both expressions are non-zero, **0** otherwise. This is *not* a short-circuit operator. This is a **non-portable extension**. **||** : The **boolean or** operator takes two expressions and returns **1** if one of the expressions is non-zero, **0** otherwise. This is *not* a short-circuit operator. This is a **non-portable extension**. ## Statements The following items are statements: 1. **E** 2. **{** **S** **;** ... **;** **S** **}** 3. **if** **(** **E** **)** **S** 4. **if** **(** **E** **)** **S** **else** **S** 5. **while** **(** **E** **)** **S** 6. **for** **(** **E** **;** **E** **;** **E** **)** **S** 7. An empty statement 8. **break** 9. **continue** 10. **quit** 11. **halt** 12. **limits** 13. A string of characters, enclosed in double quotes 14. **print** **E** **,** ... **,** **E** 15. **stream** **E** **,** ... **,** **E** 16. **I()**, **I(E)**, **I(E, E)**, and so on, where **I** is an identifier for a **void** function (see the *Void Functions* subsection of the **FUNCTIONS** section). The **E** argument(s) may also be arrays of the form **I[]**, which will automatically be turned into array references (see the *Array References* subsection of the **FUNCTIONS** section) if the corresponding parameter in the function definition is an array reference. Numbers 4, 9, 11, 12, 14, 15, and 16 are **non-portable extensions**. Also, as a **non-portable extension**, any or all of the expressions in the header of a for loop may be omitted. If the condition (second expression) is omitted, it is assumed to be a constant **1**. The **break** statement causes a loop to stop iterating and resume execution immediately following a loop. This is only allowed in loops. The **continue** statement causes a loop iteration to stop early and returns to the start of the loop, including testing the loop condition. This is only allowed in loops. The **if** **else** statement does the same thing as in C. The **quit** statement causes bc(1) to quit, even if it is on a branch that will not be executed (it is a compile-time command). The **halt** statement causes bc(1) to quit, if it is executed. (Unlike **quit** if it is on a branch of an **if** statement that is not executed, bc(1) does not quit.) The **limits** statement prints the limits that this bc(1) is subject to. This is like the **quit** statement in that it is a compile-time command. An expression by itself is evaluated and printed, followed by a newline. Both scientific notation and engineering notation are available for printing the results of expressions. Scientific notation is activated by assigning **0** to **obase**, and engineering notation is activated by assigning **1** to **obase**. To deactivate them, just assign a different value to **obase**. Scientific notation and engineering notation are disabled if bc(1) is run with either the **-s** or **-w** command-line options (or equivalents). Printing numbers in scientific notation and/or engineering notation is a **non-portable extension**. ## Strings If strings appear as a statement by themselves, they are printed without a trailing newline. In addition to appearing as a lone statement by themselves, strings can be assigned to variables and array elements. They can also be passed to functions in variable parameters. If any statement that expects a string is given a variable that had a string assigned to it, the statement acts as though it had received a string. If any math operation is attempted on a string or a variable or array element that has been assigned a string, an error is raised, and bc(1) resets (see the **RESET** section). Assigning strings to variables and array elements and passing them to functions are **non-portable extensions**. ## Print Statement The "expressions" in a **print** statement may also be strings. If they are, there are backslash escape sequences that are interpreted specially. What those sequences are, and what they cause to be printed, are shown below: **\\a**: **\\a** **\\b**: **\\b** **\\\\**: **\\** **\\e**: **\\** **\\f**: **\\f** **\\n**: **\\n** **\\q**: **"** **\\r**: **\\r** **\\t**: **\\t** Any other character following a backslash causes the backslash and character to be printed as-is. Any non-string expression in a print statement shall be assigned to **last**, like any other expression that is printed. ## Stream Statement The "expressions in a **stream** statement may also be strings. If a **stream** statement is given a string, it prints the string as though the string had appeared as its own statement. In other words, the **stream** statement prints strings normally, without a newline. If a **stream** statement is given a number, a copy of it is truncated and its absolute value is calculated. The result is then printed as though **obase** is **256** and each digit is interpreted as an 8-bit ASCII character, making it a byte stream. ## Order of Evaluation All expressions in a statment are evaluated left to right, except as necessary to maintain order of operations. This means, for example, assuming that **i** is equal to **0**, in the expression a[i++] = i++ the first (or 0th) element of **a** is set to **1**, and **i** is equal to **2** at the end of the expression. This includes function arguments. Thus, assuming **i** is equal to **0**, this means that in the expression x(i++, i++) the first argument passed to **x()** is **0**, and the second argument is **1**, while **i** is equal to **2** before the function starts executing. # FUNCTIONS Function definitions are as follows: ``` define I(I,...,I){ auto I,...,I S;...;S return(E) } ``` Any **I** in the parameter list or **auto** list may be replaced with **I[]** to make a parameter or **auto** var an array, and any **I** in the parameter list may be replaced with **\*I[]** to make a parameter an array reference. Callers of functions that take array references should not put an asterisk in the call; they must be called with just **I[]** like normal array parameters and will be automatically converted into references. As a **non-portable extension**, the opening brace of a **define** statement may appear on the next line. As a **non-portable extension**, the return statement may also be in one of the following forms: 1. **return** 2. **return** **(** **)** 3. **return** **E** The first two, or not specifying a **return** statement, is equivalent to **return (0)**, unless the function is a **void** function (see the *Void Functions* subsection below). ## Void Functions Functions can also be **void** functions, defined as follows: ``` define void I(I,...,I){ auto I,...,I S;...;S return } ``` They can only be used as standalone expressions, where such an expression would be printed alone, except in a print statement. Void functions can only use the first two **return** statements listed above. They can also omit the return statement entirely. The word "void" is not treated as a keyword; it is still possible to have variables, arrays, and functions named **void**. The word "void" is only treated specially right after the **define** keyword. This is a **non-portable extension**. ## Array References For any array in the parameter list, if the array is declared in the form ``` *I[] ``` it is a **reference**. Any changes to the array in the function are reflected, when the function returns, to the array that was passed in. Other than this, all function arguments are passed by value. This is a **non-portable extension**. # LIBRARY All of the functions below, including the functions in the extended math library (see the *Extended Library* subsection below), are available when the **-l** or **-\-mathlib** command-line flags are given, except that the extended math library is not available when the **-s** option, the **-w** option, or equivalents are given. ## Standard Library The [standard][1] defines the following functions for the math library: **s(x)** : Returns the sine of **x**, which is assumed to be in radians. This is a transcendental function (see the *Transcendental Functions* subsection below). **c(x)** : Returns the cosine of **x**, which is assumed to be in radians. This is a transcendental function (see the *Transcendental Functions* subsection below). **a(x)** : Returns the arctangent of **x**, in radians. This is a transcendental function (see the *Transcendental Functions* subsection below). **l(x)** : Returns the natural logarithm of **x**. This is a transcendental function (see the *Transcendental Functions* subsection below). **e(x)** : Returns the mathematical constant **e** raised to the power of **x**. This is a transcendental function (see the *Transcendental Functions* subsection below). **j(x, n)** : Returns the bessel integer order **n** (truncated) of **x**. This is a transcendental function (see the *Transcendental Functions* subsection below). ## Extended Library The extended library is *not* loaded when the **-s**/**-\-standard** or **-w**/**-\-warn** options are given since they are not part of the library defined by the [standard][1]. The extended library is a **non-portable extension**. **p(x, y)** : Calculates **x** to the power of **y**, even if **y** is not an integer, and returns the result to the current **scale**. It is an error if **y** is negative and **x** is **0**. This is a transcendental function (see the *Transcendental Functions* subsection below). **r(x, p)** : Returns **x** rounded to **p** decimal places according to the rounding mode [round half away from **0**][3]. **ceil(x, p)** : Returns **x** rounded to **p** decimal places according to the rounding mode [round away from **0**][6]. **f(x)** : Returns the factorial of the truncated absolute value of **x**. **perm(n, k)** : Returns the permutation of the truncated absolute value of **n** of the truncated absolute value of **k**, if **k \<= n**. If not, it returns **0**. **comb(n, k)** : Returns the combination of the truncated absolute value of **n** of the truncated absolute value of **k**, if **k \<= n**. If not, it returns **0**. **l2(x)** : Returns the logarithm base **2** of **x**. This is a transcendental function (see the *Transcendental Functions* subsection below). **l10(x)** : Returns the logarithm base **10** of **x**. This is a transcendental function (see the *Transcendental Functions* subsection below). **log(x, b)** : Returns the logarithm base **b** of **x**. This is a transcendental function (see the *Transcendental Functions* subsection below). **cbrt(x)** : Returns the cube root of **x**. **root(x, n)** : Calculates the truncated value of **n**, **r**, and returns the **r**th root of **x** to the current **scale**. If **r** is **0** or negative, this raises an error and causes bc(1) to reset (see the **RESET** section). It also raises an error and causes bc(1) to reset if **r** is even and **x** is negative. **gcd(a, b)** : Returns the greatest common divisor (factor) of the truncated absolute value of **a** and the truncated absolute value of **b**. **lcm(a, b)** : Returns the least common multiple of the truncated absolute value of **a** and the truncated absolute value of **b**. **pi(p)** : Returns **pi** to **p** decimal places. This is a transcendental function (see the *Transcendental Functions* subsection below). **t(x)** : Returns the tangent of **x**, which is assumed to be in radians. This is a transcendental function (see the *Transcendental Functions* subsection below). **a2(y, x)** : Returns the arctangent of **y/x**, in radians. If both **y** and **x** are equal to **0**, it raises an error and causes bc(1) to reset (see the **RESET** section). Otherwise, if **x** is greater than **0**, it returns **a(y/x)**. If **x** is less than **0**, and **y** is greater than or equal to **0**, it returns **a(y/x)+pi**. If **x** is less than **0**, and **y** is less than **0**, it returns **a(y/x)-pi**. If **x** is equal to **0**, and **y** is greater than **0**, it returns **pi/2**. If **x** is equal to **0**, and **y** is less than **0**, it returns **-pi/2**. This function is the same as the **atan2()** function in many programming languages. This is a transcendental function (see the *Transcendental Functions* subsection below). **sin(x)** : Returns the sine of **x**, which is assumed to be in radians. This is an alias of **s(x)**. This is a transcendental function (see the *Transcendental Functions* subsection below). **cos(x)** : Returns the cosine of **x**, which is assumed to be in radians. This is an alias of **c(x)**. This is a transcendental function (see the *Transcendental Functions* subsection below). **tan(x)** : Returns the tangent of **x**, which is assumed to be in radians. If **x** is equal to **1** or **-1**, this raises an error and causes bc(1) to reset (see the **RESET** section). This is an alias of **t(x)**. This is a transcendental function (see the *Transcendental Functions* subsection below). **atan(x)** : Returns the arctangent of **x**, in radians. This is an alias of **a(x)**. This is a transcendental function (see the *Transcendental Functions* subsection below). **atan2(y, x)** : Returns the arctangent of **y/x**, in radians. If both **y** and **x** are equal to **0**, it raises an error and causes bc(1) to reset (see the **RESET** section). Otherwise, if **x** is greater than **0**, it returns **a(y/x)**. If **x** is less than **0**, and **y** is greater than or equal to **0**, it returns **a(y/x)+pi**. If **x** is less than **0**, and **y** is less than **0**, it returns **a(y/x)-pi**. If **x** is equal to **0**, and **y** is greater than **0**, it returns **pi/2**. If **x** is equal to **0**, and **y** is less than **0**, it returns **-pi/2**. This function is the same as the **atan2()** function in many programming languages. This is an alias of **a2(y, x)**. This is a transcendental function (see the *Transcendental Functions* subsection below). **r2d(x)** : Converts **x** from radians to degrees and returns the result. This is a transcendental function (see the *Transcendental Functions* subsection below). **d2r(x)** : Converts **x** from degrees to radians and returns the result. This is a transcendental function (see the *Transcendental Functions* subsection below). **frand(p)** : Generates a pseudo-random number between **0** (inclusive) and **1** (exclusive) with the number of decimal digits after the decimal point equal to the truncated absolute value of **p**. If **p** is not **0**, then calling this function will change the value of **seed**. If **p** is **0**, then **0** is returned, and **seed** is *not* changed. **ifrand(i, p)** : Generates a pseudo-random number that is between **0** (inclusive) and the truncated absolute value of **i** (exclusive) with the number of decimal digits after the decimal point equal to the truncated absolute value of **p**. If the absolute value of **i** is greater than or equal to **2**, and **p** is not **0**, then calling this function will change the value of **seed**; otherwise, **0** is returned and **seed** is not changed. **srand(x)** : Returns **x** with its sign flipped with probability **0.5**. In other words, it randomizes the sign of **x**. **brand()** : Returns a random boolean value (either **0** or **1**). **band(a, b)** : Takes the truncated absolute value of both **a** and **b** and calculates and returns the result of the bitwise **and** operation between them. If you want to use signed two's complement arguments, use **s2u(x)** to convert. **bor(a, b)** : Takes the truncated absolute value of both **a** and **b** and calculates and returns the result of the bitwise **or** operation between them. If you want to use signed two's complement arguments, use **s2u(x)** to convert. **bxor(a, b)** : Takes the truncated absolute value of both **a** and **b** and calculates and returns the result of the bitwise **xor** operation between them. If you want to use signed two's complement arguments, use **s2u(x)** to convert. **bshl(a, b)** : Takes the truncated absolute value of both **a** and **b** and calculates and returns the result of **a** bit-shifted left by **b** places. If you want to use signed two's complement arguments, use **s2u(x)** to convert. **bshr(a, b)** : Takes the truncated absolute value of both **a** and **b** and calculates and returns the truncated result of **a** bit-shifted right by **b** places. If you want to use signed two's complement arguments, use **s2u(x)** to convert. **bnotn(x, n)** : Takes the truncated absolute value of **x** and does a bitwise not as though it has the same number of bytes as the truncated absolute value of **n**. If you want to a use signed two's complement argument, use **s2u(x)** to convert. **bnot8(x)** : Does a bitwise not of the truncated absolute value of **x** as though it has **8** binary digits (1 unsigned byte). If you want to a use signed two's complement argument, use **s2u(x)** to convert. **bnot16(x)** : Does a bitwise not of the truncated absolute value of **x** as though it has **16** binary digits (2 unsigned bytes). If you want to a use signed two's complement argument, use **s2u(x)** to convert. **bnot32(x)** : Does a bitwise not of the truncated absolute value of **x** as though it has **32** binary digits (4 unsigned bytes). If you want to a use signed two's complement argument, use **s2u(x)** to convert. **bnot64(x)** : Does a bitwise not of the truncated absolute value of **x** as though it has **64** binary digits (8 unsigned bytes). If you want to a use signed two's complement argument, use **s2u(x)** to convert. **bnot(x)** : Does a bitwise not of the truncated absolute value of **x** as though it has the minimum number of power of two unsigned bytes. If you want to a use signed two's complement argument, use **s2u(x)** to convert. **brevn(x, n)** : Runs a bit reversal on the truncated absolute value of **x** as though it has the same number of 8-bit bytes as the truncated absolute value of **n**. If you want to a use signed two's complement argument, use **s2u(x)** to convert. **brev8(x)** : Runs a bit reversal on the truncated absolute value of **x** as though it has 8 binary digits (1 unsigned byte). If you want to a use signed two's complement argument, use **s2u(x)** to convert. **brev16(x)** : Runs a bit reversal on the truncated absolute value of **x** as though it has 16 binary digits (2 unsigned bytes). If you want to a use signed two's complement argument, use **s2u(x)** to convert. **brev32(x)** : Runs a bit reversal on the truncated absolute value of **x** as though it has 32 binary digits (4 unsigned bytes). If you want to a use signed two's complement argument, use **s2u(x)** to convert. **brev64(x)** : Runs a bit reversal on the truncated absolute value of **x** as though it has 64 binary digits (8 unsigned bytes). If you want to a use signed two's complement argument, use **s2u(x)** to convert. **brev(x)** : Runs a bit reversal on the truncated absolute value of **x** as though it has the minimum number of power of two unsigned bytes. If you want to a use signed two's complement argument, use **s2u(x)** to convert. **broln(x, p, n)** : Does a left bitwise rotatation of the truncated absolute value of **x**, as though it has the same number of unsigned 8-bit bytes as the truncated absolute value of **n**, by the number of places equal to the truncated absolute value of **p** modded by the **2** to the power of the number of binary digits in **n** 8-bit bytes. If you want to a use signed two's complement argument, use **s2u(x)** to convert. **brol8(x, p)** : Does a left bitwise rotatation of the truncated absolute value of **x**, as though it has **8** binary digits (**1** unsigned byte), by the number of places equal to the truncated absolute value of **p** modded by **2** to the power of **8**. If you want to a use signed two's complement argument, use **s2u(x)** to convert. **brol16(x, p)** : Does a left bitwise rotatation of the truncated absolute value of **x**, as though it has **16** binary digits (**2** unsigned bytes), by the number of places equal to the truncated absolute value of **p** modded by **2** to the power of **16**. If you want to a use signed two's complement argument, use **s2u(x)** to convert. **brol32(x, p)** : Does a left bitwise rotatation of the truncated absolute value of **x**, as though it has **32** binary digits (**2** unsigned bytes), by the number of places equal to the truncated absolute value of **p** modded by **2** to the power of **32**. If you want to a use signed two's complement argument, use **s2u(x)** to convert. **brol64(x, p)** : Does a left bitwise rotatation of the truncated absolute value of **x**, as though it has **64** binary digits (**2** unsigned bytes), by the number of places equal to the truncated absolute value of **p** modded by **2** to the power of **64**. If you want to a use signed two's complement argument, use **s2u(x)** to convert. **brol(x, p)** : Does a left bitwise rotatation of the truncated absolute value of **x**, as though it has the minimum number of power of two unsigned 8-bit bytes, by the number of places equal to the truncated absolute value of **p** modded by 2 to the power of the number of binary digits in the minimum number of 8-bit bytes. If you want to a use signed two's complement argument, use **s2u(x)** to convert. **brorn(x, p, n)** : Does a right bitwise rotatation of the truncated absolute value of **x**, as though it has the same number of unsigned 8-bit bytes as the truncated absolute value of **n**, by the number of places equal to the truncated absolute value of **p** modded by the **2** to the power of the number of binary digits in **n** 8-bit bytes. If you want to a use signed two's complement argument, use **s2u(x)** to convert. **bror8(x, p)** : Does a right bitwise rotatation of the truncated absolute value of **x**, as though it has **8** binary digits (**1** unsigned byte), by the number of places equal to the truncated absolute value of **p** modded by **2** to the power of **8**. If you want to a use signed two's complement argument, use **s2u(x)** to convert. **bror16(x, p)** : Does a right bitwise rotatation of the truncated absolute value of **x**, as though it has **16** binary digits (**2** unsigned bytes), by the number of places equal to the truncated absolute value of **p** modded by **2** to the power of **16**. If you want to a use signed two's complement argument, use **s2u(x)** to convert. **bror32(x, p)** : Does a right bitwise rotatation of the truncated absolute value of **x**, as though it has **32** binary digits (**2** unsigned bytes), by the number of places equal to the truncated absolute value of **p** modded by **2** to the power of **32**. If you want to a use signed two's complement argument, use **s2u(x)** to convert. **bror64(x, p)** : Does a right bitwise rotatation of the truncated absolute value of **x**, as though it has **64** binary digits (**2** unsigned bytes), by the number of places equal to the truncated absolute value of **p** modded by **2** to the power of **64**. If you want to a use signed two's complement argument, use **s2u(x)** to convert. **bror(x, p)** : Does a right bitwise rotatation of the truncated absolute value of **x**, as though it has the minimum number of power of two unsigned 8-bit bytes, by the number of places equal to the truncated absolute value of **p** modded by 2 to the power of the number of binary digits in the minimum number of 8-bit bytes. If you want to a use signed two's complement argument, use **s2u(x)** to convert. **bmodn(x, n)** : Returns the modulus of the truncated absolute value of **x** by **2** to the power of the multiplication of the truncated absolute value of **n** and **8**. If you want to a use signed two's complement argument, use **s2u(x)** to convert. **bmod8(x, n)** : Returns the modulus of the truncated absolute value of **x** by **2** to the power of **8**. If you want to a use signed two's complement argument, use **s2u(x)** to convert. **bmod16(x, n)** : Returns the modulus of the truncated absolute value of **x** by **2** to the power of **16**. If you want to a use signed two's complement argument, use **s2u(x)** to convert. **bmod32(x, n)** : Returns the modulus of the truncated absolute value of **x** by **2** to the power of **32**. If you want to a use signed two's complement argument, use **s2u(x)** to convert. **bmod64(x, n)** : Returns the modulus of the truncated absolute value of **x** by **2** to the power of **64**. If you want to a use signed two's complement argument, use **s2u(x)** to convert. **bunrev(t)** : Assumes **t** is a bitwise-reversed number with an extra set bit one place more significant than the real most significant bit (which was the least significant bit in the original number). This number is reversed and returned without the extra set bit. This function is used to implement other bitwise functions; it is not meant to be used by users, but it can be. **plz(x)** : If **x** is not equal to **0** and greater that **-1** and less than **1**, it is printed with a leading zero, regardless of the use of the **-z** option (see the **OPTIONS** section) and without a trailing newline. Otherwise, **x** is printed normally, without a trailing newline. **plznl(x)** : If **x** is not equal to **0** and greater that **-1** and less than **1**, it is printed with a leading zero, regardless of the use of the **-z** option (see the **OPTIONS** section) and with a trailing newline. Otherwise, **x** is printed normally, with a trailing newline. **pnlz(x)** : If **x** is not equal to **0** and greater that **-1** and less than **1**, it is printed without a leading zero, regardless of the use of the **-z** option (see the **OPTIONS** section) and without a trailing newline. Otherwise, **x** is printed normally, without a trailing newline. **pnlznl(x)** : If **x** is not equal to **0** and greater that **-1** and less than **1**, it is printed without a leading zero, regardless of the use of the **-z** option (see the **OPTIONS** section) and with a trailing newline. Otherwise, **x** is printed normally, with a trailing newline. **ubytes(x)** : Returns the numbers of unsigned integer bytes required to hold the truncated absolute value of **x**. **sbytes(x)** : Returns the numbers of signed, two's-complement integer bytes required to hold the truncated value of **x**. **s2u(x)** : Returns **x** if it is non-negative. If it *is* negative, then it calculates what **x** would be as a 2's-complement signed integer and returns the non-negative integer that would have the same representation in binary. **s2un(x,n)** : Returns **x** if it is non-negative. If it *is* negative, then it calculates what **x** would be as a 2's-complement signed integer with **n** bytes and returns the non-negative integer that would have the same representation in binary. If **x** cannot fit into **n** 2's-complement signed bytes, it is truncated to fit. **hex(x)** : Outputs the hexadecimal (base **16**) representation of **x**. This is a **void** function (see the *Void Functions* subsection of the **FUNCTIONS** section). **binary(x)** : Outputs the binary (base **2**) representation of **x**. This is a **void** function (see the *Void Functions* subsection of the **FUNCTIONS** section). **output(x, b)** : Outputs the base **b** representation of **x**. This is a **void** function (see the *Void Functions* subsection of the **FUNCTIONS** section). **uint(x)** : Outputs the representation, in binary and hexadecimal, of **x** as an unsigned integer in as few power of two bytes as possible. Both outputs are split into bytes separated by spaces. If **x** is not an integer or is negative, an error message is printed instead, but bc(1) is not reset (see the **RESET** section). This is a **void** function (see the *Void Functions* subsection of the **FUNCTIONS** section). **int(x)** : Outputs the representation, in binary and hexadecimal, of **x** as a signed, two's-complement integer in as few power of two bytes as possible. Both outputs are split into bytes separated by spaces. If **x** is not an integer, an error message is printed instead, but bc(1) is not reset (see the **RESET** section). This is a **void** function (see the *Void Functions* subsection of the **FUNCTIONS** section). **uintn(x, n)** : Outputs the representation, in binary and hexadecimal, of **x** as an unsigned integer in **n** bytes. Both outputs are split into bytes separated by spaces. If **x** is not an integer, is negative, or cannot fit into **n** bytes, an error message is printed instead, but bc(1) is not reset (see the **RESET** section). This is a **void** function (see the *Void Functions* subsection of the **FUNCTIONS** section). **intn(x, n)** : Outputs the representation, in binary and hexadecimal, of **x** as a signed, two's-complement integer in **n** bytes. Both outputs are split into bytes separated by spaces. If **x** is not an integer or cannot fit into **n** bytes, an error message is printed instead, but bc(1) is not reset (see the **RESET** section). This is a **void** function (see the *Void Functions* subsection of the **FUNCTIONS** section). **uint8(x)** : Outputs the representation, in binary and hexadecimal, of **x** as an unsigned integer in **1** byte. Both outputs are split into bytes separated by spaces. If **x** is not an integer, is negative, or cannot fit into **1** byte, an error message is printed instead, but bc(1) is not reset (see the **RESET** section). This is a **void** function (see the *Void Functions* subsection of the **FUNCTIONS** section). **int8(x)** : Outputs the representation, in binary and hexadecimal, of **x** as a signed, two's-complement integer in **1** byte. Both outputs are split into bytes separated by spaces. If **x** is not an integer or cannot fit into **1** byte, an error message is printed instead, but bc(1) is not reset (see the **RESET** section). This is a **void** function (see the *Void Functions* subsection of the **FUNCTIONS** section). **uint16(x)** : Outputs the representation, in binary and hexadecimal, of **x** as an unsigned integer in **2** bytes. Both outputs are split into bytes separated by spaces. If **x** is not an integer, is negative, or cannot fit into **2** bytes, an error message is printed instead, but bc(1) is not reset (see the **RESET** section). This is a **void** function (see the *Void Functions* subsection of the **FUNCTIONS** section). **int16(x)** : Outputs the representation, in binary and hexadecimal, of **x** as a signed, two's-complement integer in **2** bytes. Both outputs are split into bytes separated by spaces. If **x** is not an integer or cannot fit into **2** bytes, an error message is printed instead, but bc(1) is not reset (see the **RESET** section). This is a **void** function (see the *Void Functions* subsection of the **FUNCTIONS** section). **uint32(x)** : Outputs the representation, in binary and hexadecimal, of **x** as an unsigned integer in **4** bytes. Both outputs are split into bytes separated by spaces. If **x** is not an integer, is negative, or cannot fit into **4** bytes, an error message is printed instead, but bc(1) is not reset (see the **RESET** section). This is a **void** function (see the *Void Functions* subsection of the **FUNCTIONS** section). **int32(x)** : Outputs the representation, in binary and hexadecimal, of **x** as a signed, two's-complement integer in **4** bytes. Both outputs are split into bytes separated by spaces. If **x** is not an integer or cannot fit into **4** bytes, an error message is printed instead, but bc(1) is not reset (see the **RESET** section). This is a **void** function (see the *Void Functions* subsection of the **FUNCTIONS** section). **uint64(x)** : Outputs the representation, in binary and hexadecimal, of **x** as an unsigned integer in **8** bytes. Both outputs are split into bytes separated by spaces. If **x** is not an integer, is negative, or cannot fit into **8** bytes, an error message is printed instead, but bc(1) is not reset (see the **RESET** section). This is a **void** function (see the *Void Functions* subsection of the **FUNCTIONS** section). **int64(x)** : Outputs the representation, in binary and hexadecimal, of **x** as a signed, two's-complement integer in **8** bytes. Both outputs are split into bytes separated by spaces. If **x** is not an integer or cannot fit into **8** bytes, an error message is printed instead, but bc(1) is not reset (see the **RESET** section). This is a **void** function (see the *Void Functions* subsection of the **FUNCTIONS** section). **hex_uint(x, n)** : Outputs the representation of the truncated absolute value of **x** as an unsigned integer in hexadecimal using **n** bytes. Not all of the value will be output if **n** is too small. This is a **void** function (see the *Void Functions* subsection of the **FUNCTIONS** section). **binary_uint(x, n)** : Outputs the representation of the truncated absolute value of **x** as an unsigned integer in binary using **n** bytes. Not all of the value will be output if **n** is too small. This is a **void** function (see the *Void Functions* subsection of the **FUNCTIONS** section). **output_uint(x, n)** : Outputs the representation of the truncated absolute value of **x** as an unsigned integer in the current **obase** (see the **SYNTAX** section) using **n** bytes. Not all of the value will be output if **n** is too small. This is a **void** function (see the *Void Functions* subsection of the **FUNCTIONS** section). **output_byte(x, i)** : Outputs byte **i** of the truncated absolute value of **x**, where **0** is the least significant byte and **number_of_bytes - 1** is the most significant byte. This is a **void** function (see the *Void Functions* subsection of the **FUNCTIONS** section). ## Transcendental Functions All transcendental functions can return slightly inaccurate results (up to 1 [ULP][4]). This is unavoidable, and [this article][5] explains why it is impossible and unnecessary to calculate exact results for the transcendental functions. Because of the possible inaccuracy, I recommend that users call those functions with the precision (**scale**) set to at least 1 higher than is necessary. If exact results are *absolutely* required, users can double the precision (**scale**) and then truncate. The transcendental functions in the standard math library are: * **s(x)** * **c(x)** * **a(x)** * **l(x)** * **e(x)** * **j(x, n)** The transcendental functions in the extended math library are: * **l2(x)** * **l10(x)** * **log(x, b)** * **pi(p)** * **t(x)** * **a2(y, x)** * **sin(x)** * **cos(x)** * **tan(x)** * **atan(x)** * **atan2(y, x)** * **r2d(x)** * **d2r(x)** # RESET When bc(1) encounters an error or a signal that it has a non-default handler for, it resets. This means that several things happen. First, any functions that are executing are stopped and popped off the stack. The behavior is not unlike that of exceptions in programming languages. Then the execution point is set so that any code waiting to execute (after all functions returned) is skipped. Thus, when bc(1) resets, it skips any remaining code waiting to be executed. Then, if it is interactive mode, and the error was not a fatal error (see the **EXIT STATUS** section), it asks for more input; otherwise, it exits with the appropriate return code. Note that this reset behavior is different from the GNU bc(1), which attempts to start executing the statement right after the one that caused an error. # PERFORMANCE Most bc(1) implementations use **char** types to calculate the value of **1** decimal digit at a time, but that can be slow. This bc(1) does something different. It uses large integers to calculate more than **1** decimal digit at a time. If built in a environment where **BC_LONG_BIT** (see the **LIMITS** section) is **64**, then each integer has **9** decimal digits. If built in an environment where **BC_LONG_BIT** is **32** then each integer has **4** decimal digits. This value (the number of decimal digits per large integer) is called **BC_BASE_DIGS**. The actual values of **BC_LONG_BIT** and **BC_BASE_DIGS** can be queried with the **limits** statement. In addition, this bc(1) uses an even larger integer for overflow checking. This integer type depends on the value of **BC_LONG_BIT**, but is always at least twice as large as the integer type used to store digits. # LIMITS The following are the limits on bc(1): **BC_LONG_BIT** : The number of bits in the **long** type in the environment where bc(1) was built. This determines how many decimal digits can be stored in a single large integer (see the **PERFORMANCE** section). **BC_BASE_DIGS** : The number of decimal digits per large integer (see the **PERFORMANCE** section). Depends on **BC_LONG_BIT**. **BC_BASE_POW** : The max decimal number that each large integer can store (see **BC_BASE_DIGS**) plus **1**. Depends on **BC_BASE_DIGS**. **BC_OVERFLOW_MAX** : The max number that the overflow type (see the **PERFORMANCE** section) can hold. Depends on **BC_LONG_BIT**. **BC_BASE_MAX** : The maximum output base. Set at **BC_BASE_POW**. **BC_DIM_MAX** : The maximum size of arrays. Set at **SIZE_MAX-1**. **BC_SCALE_MAX** : The maximum **scale**. Set at **BC_OVERFLOW_MAX-1**. **BC_STRING_MAX** : The maximum length of strings. Set at **BC_OVERFLOW_MAX-1**. **BC_NAME_MAX** : The maximum length of identifiers. Set at **BC_OVERFLOW_MAX-1**. **BC_NUM_MAX** : The maximum length of a number (in decimal digits), which includes digits after the decimal point. Set at **BC_OVERFLOW_MAX-1**. **BC_RAND_MAX** : The maximum integer (inclusive) returned by the **rand()** operand. Set at **2\^BC_LONG_BIT-1**. Exponent : The maximum allowable exponent (positive or negative). Set at **BC_OVERFLOW_MAX**. Number of vars : The maximum number of vars/arrays. Set at **SIZE_MAX-1**. The actual values can be queried with the **limits** statement. These limits are meant to be effectively non-existent; the limits are so large (at least on 64-bit machines) that there should not be any point at which they become a problem. In fact, memory should be exhausted before these limits should be hit. # ENVIRONMENT VARIABLES bc(1) recognizes the following environment variables: **POSIXLY_CORRECT** : If this variable exists (no matter the contents), bc(1) behaves as if the **-s** option was given. **BC_ENV_ARGS** : This is another way to give command-line arguments to bc(1). They should be in the same format as all other command-line arguments. These are always processed first, so any files given in **BC_ENV_ARGS** will be processed before arguments and files given on the command-line. This gives the user the ability to set up "standard" options and files to be used at every invocation. The most useful thing for such files to contain would be useful functions that the user might want every time bc(1) runs. The code that parses **BC_ENV_ARGS** will correctly handle quoted arguments, but it does not understand escape sequences. For example, the string **"/home/gavin/some bc file.bc"** will be correctly parsed, but the string **"/home/gavin/some \"bc\" file.bc"** will include the backslashes. The quote parsing will handle either kind of quotes, **'** or **"**. Thus, if you have a file with any number of single quotes in the name, you can use double quotes as the outside quotes, as in **"some 'bc' file.bc"**, and vice versa if you have a file with double quotes. However, handling a file with both kinds of quotes in **BC_ENV_ARGS** is not supported due to the complexity of the parsing, though such files are still supported on the command-line where the parsing is done by the shell. **BC_LINE_LENGTH** : If this environment variable exists and contains an integer that is greater than **1** and is less than **UINT16_MAX** (**2\^16-1**), bc(1) will output lines to that length, including the backslash (**\\**). The default line length is **70**. The special value of **0** will disable line length checking and print numbers without regard to line length and without backslashes and newlines. **BC_BANNER** : If this environment variable exists and contains an integer, then a non-zero value activates the copyright banner when bc(1) is in interactive mode, while zero deactivates it. If bc(1) is not in interactive mode (see the **INTERACTIVE MODE** section), then this environment variable has no effect because bc(1) does not print the banner when not in interactive mode. This environment variable overrides the default, which can be queried with the **-h** or **-\-help** options. **BC_SIGINT_RESET** : If bc(1) is not in interactive mode (see the **INTERACTIVE MODE** section), then this environment variable has no effect because bc(1) exits on **SIGINT** when not in interactive mode. However, when bc(1) is in interactive mode, then if this environment variable exists and contains an integer, a non-zero value makes bc(1) reset on **SIGINT**, rather than exit, and zero makes bc(1) exit. If this environment variable exists and is *not* an integer, then bc(1) will exit on **SIGINT**. This environment variable overrides the default, which can be queried with the **-h** or **-\-help** options. **BC_TTY_MODE** : If TTY mode is *not* available (see the **TTY MODE** section), then this environment variable has no effect. However, when TTY mode is available, then if this environment variable exists and contains an integer, then a non-zero value makes bc(1) use TTY mode, and zero makes bc(1) not use TTY mode. This environment variable overrides the default, which can be queried with the **-h** or **-\-help** options. **BC_PROMPT** : If TTY mode is *not* available (see the **TTY MODE** section), then this environment variable has no effect. However, when TTY mode is available, then if this environment variable exists and contains an integer, a non-zero value makes bc(1) use a prompt, and zero or a non-integer makes bc(1) not use a prompt. If this environment variable does not exist and **BC_TTY_MODE** does, then the value of the **BC_TTY_MODE** environment variable is used. This environment variable and the **BC_TTY_MODE** environment variable override the default, which can be queried with the **-h** or **-\-help** options. +**BC_EXPR_EXIT** + +: If any expressions or expression files are given on the command-line with + **-e**, **-\-expression**, **-f**, or **-\-file**, then if this environment + variable exists and contains an integer, a non-zero value makes bc(1) exit + after executing the expressions and expression files, and a non-zero value + makes bc(1) not exit. + + This environment variable overrides the default, which can be queried with + the **-h** or **-\-help** options. + # EXIT STATUS bc(1) returns the following exit statuses: **0** : No error. **1** : A math error occurred. This follows standard practice of using **1** for expected errors, since math errors will happen in the process of normal execution. Math errors include divide by **0**, taking the square root of a negative number, using a negative number as a bound for the pseudo-random number generator, attempting to convert a negative number to a hardware integer, overflow when converting a number to a hardware integer, overflow when calculating the size of a number, and attempting to use a non-integer where an integer is required. Converting to a hardware integer happens for the second operand of the power (**\^**), places (**\@**), left shift (**\<\<**), and right shift (**\>\>**) operators and their corresponding assignment operators. **2** : A parse error occurred. Parse errors include unexpected **EOF**, using an invalid character, failing to find the end of a string or comment, using a token where it is invalid, giving an invalid expression, giving an invalid print statement, giving an invalid function definition, attempting to assign to an expression that is not a named expression (see the *Named Expressions* subsection of the **SYNTAX** section), giving an invalid **auto** list, having a duplicate **auto**/function parameter, failing to find the end of a code block, attempting to return a value from a **void** function, attempting to use a variable as a reference, and using any extensions when the option **-s** or any equivalents were given. **3** : A runtime error occurred. Runtime errors include assigning an invalid number to any global (**ibase**, **obase**, or **scale**), giving a bad expression to a **read()** call, calling **read()** inside of a **read()** call, type errors, passing the wrong number of arguments to functions, attempting to call an undefined function, and attempting to use a **void** function call as a value in an expression. **4** : A fatal error occurred. Fatal errors include memory allocation errors, I/O errors, failing to open files, attempting to use files that do not have only ASCII characters (bc(1) only accepts ASCII characters), attempting to open a directory as a file, and giving invalid command-line options. The exit status **4** is special; when a fatal error occurs, bc(1) always exits and returns **4**, no matter what mode bc(1) is in. The other statuses will only be returned when bc(1) is not in interactive mode (see the **INTERACTIVE MODE** section), since bc(1) resets its state (see the **RESET** section) and accepts more input when one of those errors occurs in interactive mode. This is also the case when interactive mode is forced by the **-i** flag or **-\-interactive** option. These exit statuses allow bc(1) to be used in shell scripting with error checking, and its normal behavior can be forced by using the **-i** flag or **-\-interactive** option. # INTERACTIVE MODE Per the [standard][1], bc(1) has an interactive mode and a non-interactive mode. Interactive mode is turned on automatically when both **stdin** and **stdout** are hooked to a terminal, but the **-i** flag and **-\-interactive** option can turn it on in other situations. In interactive mode, bc(1) attempts to recover from errors (see the **RESET** section), and in normal execution, flushes **stdout** as soon as execution is done for the current input. bc(1) may also reset on **SIGINT** instead of exit, depending on the contents of, or default for, the **BC_SIGINT_RESET** environment variable (see the **ENVIRONMENT VARIABLES** section). # TTY MODE If **stdin**, **stdout**, and **stderr** are all connected to a TTY, then "TTY mode" is considered to be available, and thus, bc(1) can turn on TTY mode, subject to some settings. If there is the environment variable **BC_TTY_MODE** in the environment (see the **ENVIRONMENT VARIABLES** section), then if that environment variable contains a non-zero integer, bc(1) will turn on TTY mode when **stdin**, **stdout**, and **stderr** are all connected to a TTY. If the **BC_TTY_MODE** environment variable exists but is *not* a non-zero integer, then bc(1) will not turn TTY mode on. If the environment variable **BC_TTY_MODE** does *not* exist, the default setting is used. The default setting can be queried with the **-h** or **-\-help** options. TTY mode is different from interactive mode because interactive mode is required in the [bc(1) specification][1], and interactive mode requires only **stdin** and **stdout** to be connected to a terminal. ## Command-Line History Command-line history is only enabled if TTY mode is, i.e., that **stdin**, **stdout**, and **stderr** are connected to a TTY and the **BC_TTY_MODE** environment variable (see the **ENVIRONMENT VARIABLES** section) and its default do not disable TTY mode. See the **COMMAND LINE HISTORY** section for more information. ## Prompt If TTY mode is available, then a prompt can be enabled. Like TTY mode itself, it can be turned on or off with an environment variable: **BC_PROMPT** (see the **ENVIRONMENT VARIABLES** section). If the environment variable **BC_PROMPT** exists and is a non-zero integer, then the prompt is turned on when **stdin**, **stdout**, and **stderr** are connected to a TTY and the **-P** and **-\-no-prompt** options were not used. The read prompt will be turned on under the same conditions, except that the **-R** and **-\-no-read-prompt** options must also not be used. However, if **BC_PROMPT** does not exist, the prompt can be enabled or disabled with the **BC_TTY_MODE** environment variable, the **-P** and **-\-no-prompt** options, and the **-R** and **-\-no-read-prompt** options. See the **ENVIRONMENT VARIABLES** and **OPTIONS** sections for more details. # SIGNAL HANDLING Sending a **SIGINT** will cause bc(1) to do one of two things. If bc(1) is not in interactive mode (see the **INTERACTIVE MODE** section), or the **BC_SIGINT_RESET** environment variable (see the **ENVIRONMENT VARIABLES** section), or its default, is either not an integer or it is zero, bc(1) will exit. However, if bc(1) is in interactive mode, and the **BC_SIGINT_RESET** or its default is an integer and non-zero, then bc(1) will stop executing the current input and reset (see the **RESET** section) upon receiving a **SIGINT**. Note that "current input" can mean one of two things. If bc(1) is processing input from **stdin** in interactive mode, it will ask for more input. If bc(1) is processing input from a file in interactive mode, it will stop processing the file and start processing the next file, if one exists, or ask for input from **stdin** if no other file exists. This means that if a **SIGINT** is sent to bc(1) as it is executing a file, it can seem as though bc(1) did not respond to the signal since it will immediately start executing the next file. This is by design; most files that users execute when interacting with bc(1) have function definitions, which are quick to parse. If a file takes a long time to execute, there may be a bug in that file. The rest of the files could still be executed without problem, allowing the user to continue. **SIGTERM** and **SIGQUIT** cause bc(1) to clean up and exit, and it uses the default handler for all other signals. The one exception is **SIGHUP**; in that case, and only when bc(1) is in TTY mode (see the **TTY MODE** section), a **SIGHUP** will cause bc(1) to clean up and exit. # COMMAND LINE HISTORY bc(1) supports interactive command-line editing. If bc(1) can be in TTY mode (see the **TTY MODE** section), history can be enabled. This means that command-line history can only be enabled when **stdin**, **stdout**, and **stderr** are all connected to a TTY. Like TTY mode itself, it can be turned on or off with the environment variable **BC_TTY_MODE** (see the **ENVIRONMENT VARIABLES** section). If history is enabled, previous lines can be recalled and edited with the arrow keys. **Note**: tabs are converted to 8 spaces. # SEE ALSO dc(1) # STANDARDS bc(1) is compliant with the [IEEE Std 1003.1-2017 (“POSIX.1-2017”)][1] specification. The flags **-efghiqsvVw**, all long options, and the extensions noted above are extensions to that specification. Note that the specification explicitly says that bc(1) only accepts numbers that use a period (**.**) as a radix point, regardless of the value of **LC_NUMERIC**. # BUGS None are known. Report bugs at https://git.yzena.com/gavin/bc. # AUTHORS Gavin D. Howard and contributors. [1]: https://pubs.opengroup.org/onlinepubs/9699919799/utilities/bc.html [2]: https://www.gnu.org/software/bc/ [3]: https://en.wikipedia.org/wiki/Rounding#Round_half_away_from_zero [4]: https://en.wikipedia.org/wiki/Unit_in_the_last_place [5]: https://people.eecs.berkeley.edu/~wkahan/LOG10HAF.TXT [6]: https://en.wikipedia.org/wiki/Rounding#Rounding_away_from_zero diff --git a/contrib/bc/manuals/build.md b/contrib/bc/manuals/build.md index 1ed2b269f13c..aa0ed78e2d72 100644 --- a/contrib/bc/manuals/build.md +++ b/contrib/bc/manuals/build.md @@ -1,838 +1,855 @@ # Build This `bc` attempts to be as portable as possible. It can be built on any POSIX-compliant system. To accomplish that, a POSIX-compatible, custom `configure.sh` script is used to select build options, compiler, and compiler flags and generate a `Makefile`. The general form of configuring, building, and installing this `bc` is as follows: ``` [ENVIRONMENT_VARIABLE=...] ./configure.sh [build_options...] make make install ``` To get all of the options, including any useful environment variables, use either one of the following commands: ``` ./configure.sh -h ./configure.sh --help ``` ***WARNING***: even though `configure.sh` supports both option types, short and long, it does not support handling both at the same time. Use only one type. To learn the available `make` targets run the following command after running the `configure.sh` script: ``` make help ``` See [Build Environment Variables][4] for a more detailed description of all accepted environment variables and [Build Options][5] for more detail about all accepted build options. ## Windows For releases, Windows builds of `bc`, `dc`, and `bcl` are available for download from and GitHub. However, if you wish to build it yourself, this `bc` can be built using Visual Studio or MSBuild. Unfortunately, only one build configuration (besides Debug or Release) is supported: extra math enabled, history and NLS (locale support) disabled, with both calculators built. The default [settings][11] are `BC_BANNER=1`, `{BC,DC}_SIGINT_RESET=0`, `{BC,DC}_TTY_MODE=1`, `{BC,DC}_PROMPT=1`. The library can also be built on Windows. ### Visual Studio In Visual Studio, open up the solution file (`bc.sln` for `bc`, or `bcl.sln` for the library), select the desired configuration, and build. ### MSBuild To build with MSBuild, first, *be sure that you are using the MSBuild that comes with Visual Studio*. To build `bc`, run the following from the root directory: ``` msbuild -property:Configuration= vs/bc.sln ``` where `` is either one of `Debug` or `Release`. To build the library, run the following from the root directory: ``` msbuild -property:Configuration= vs/bcl.sln ``` where `` is either one of `Debug`, `ReleaseMD`, or `ReleaseMT`. ## POSIX-Compatible Systems Building `bc`, `dc`, and `bcl` (the library) is more complex than on Windows because many build options are supported. +### Out-of-Source Builds + +Out-of-source builds are done by calling `configure.sh` from the directory where +the build will happen. The `Makefile` is generated into that directory, and the +build can happen normally from there. + +For example, if the source is in `bc`, the build should happen in `build`, then +call `configure.sh` and `make` like so: + +``` +../bc/configure.sh +make +``` + +***WARNING***: The path to `configure.sh` from the build directory must not have +spaces because `make` does not support target names with spaces. + ### Cross Compiling To cross-compile this `bc`, an appropriate compiler must be present and assigned to the environment variable `HOSTCC` or `HOST_CC` (the two are equivalent, though `HOSTCC` is prioritized). This is in order to bootstrap core file(s), if the architectures are not compatible (i.e., unlike i686 on x86_64). Thus, the approach is: ``` HOSTCC="/path/to/native/compiler" ./configure.sh make make install ``` `HOST_CC` will work in exactly the same way. `HOSTCFLAGS` and `HOST_CFLAGS` can be used to set compiler flags for `HOSTCC`. (The two are equivalent, as `HOSTCC` and `HOST_CC` are.) `HOSTCFLAGS` is prioritized over `HOST_CFLAGS`. If neither are present, `HOSTCC` (or `HOST_CC`) uses `CFLAGS` (see [Build Environment Variables][4] for more details). It is expected that `CC` produces code for the target system and `HOSTCC` produces code for the host system. See [Build Environment Variables][4] for more details. If an emulator is necessary to run the bootstrap binaries, it can be set with the environment variable `GEN_EMU`. ### Build Environment Variables This `bc` supports `CC`, `HOSTCC`, `HOST_CC`, `CFLAGS`, `HOSTCFLAGS`, `HOST_CFLAGS`, `CPPFLAGS`, `LDFLAGS`, `LDLIBS`, `PREFIX`, `DESTDIR`, `BINDIR`, `DATAROOTDIR`, `DATADIR`, `MANDIR`, `MAN1DIR`, `LOCALEDIR` `EXECSUFFIX`, `EXECPREFIX`, `LONG_BIT`, `GEN_HOST`, and `GEN_EMU` environment variables in `configure.sh`. Any values of those variables given to `configure.sh` will be put into the generated Makefile. More detail on what those environment variables do can be found in the following sections. #### `CC` C compiler for the target system. `CC` must be compatible with POSIX `c99` behavior and options. However, **I encourage users to use any C99 or C11 compatible compiler they wish.** If there is a space in the basename of the compiler, the items after the first space are assumed to be compiler flags, and in that case, the flags are automatically moved into CFLAGS. Defaults to `c99`. #### `HOSTCC` or `HOST_CC` C compiler for the host system, used only in [cross compiling][6]. Must be compatible with POSIX `c99` behavior and options. If there is a space in the basename of the compiler, the items after the first space are assumed to be compiler flags, and in that case, the flags are automatically moved into HOSTCFLAGS. Defaults to `$CC`. #### `CFLAGS` Command-line flags that will be passed verbatim to `CC`. Defaults to empty. #### `HOSTCFLAGS` or `HOST_CFLAGS` Command-line flags that will be passed verbatim to `HOSTCC` or `HOST_CC`. Defaults to `$CFLAGS`. #### `CPPFLAGS` Command-line flags for the C preprocessor. These are also passed verbatim to both compilers (`CC` and `HOSTCC`); they are supported just for legacy reasons. Defaults to empty. #### `LDFLAGS` Command-line flags for the linker. These are also passed verbatim to both compilers (`CC` and `HOSTCC`); they are supported just for legacy reasons. Defaults to empty. #### `LDLIBS` Libraries to link to. These are also passed verbatim to both compilers (`CC` and `HOSTCC`); they are supported just for legacy reasons and for cross compiling with different C standard libraries (like [musl][3]). Defaults to empty. #### `PREFIX` The prefix to install to. Can be overridden by passing the `--prefix` option to `configure.sh`. Defaults to `/usr/local`. #### `DESTDIR` Path to prepend onto `PREFIX`. This is mostly for distro and package maintainers. This can be passed either to `configure.sh` or `make install`. If it is passed to both, the one given to `configure.sh` takes precedence. Defaults to empty. #### `BINDIR` The directory to install binaries in. Can be overridden by passing the `--bindir` option to `configure.sh`. Defaults to `$PREFIX/bin`. #### `INCLUDEDIR` The directory to install header files in. Can be overridden by passing the `--includedir` option to `configure.sh`. Defaults to `$PREFIX/include`. #### `LIBDIR` The directory to install libraries in. Can be overridden by passing the `--libdir` option to `configure.sh`. Defaults to `$PREFIX/lib`. #### `DATAROOTDIR` The root directory to install data files in. Can be overridden by passing the `--datarootdir` option to `configure.sh`. Defaults to `$PREFIX/share`. #### `DATADIR` The directory to install data files in. Can be overridden by passing the `--datadir` option to `configure.sh`. Defaults to `$DATAROOTDIR`. #### `MANDIR` The directory to install manpages in. Can be overridden by passing the `--mandir` option to `configure.sh`. Defaults to `$DATADIR/man` #### `MAN1DIR` The directory to install Section 1 manpages in. Because both `bc` and `dc` are Section 1 commands, this is the only relevant section directory. Can be overridden by passing the `--man1dir` option to `configure.sh`. Defaults to `$MANDIR/man1`. #### `LOCALEDIR` The directory to install locales in. Can be overridden by passing the `--localedir` option to `configure.sh`. Defaults to `$DATAROOTDIR/locale`. #### `EXECSUFFIX` The suffix to append onto the executable names *when installing*. This is for packagers and distro maintainers who want this `bc` as an option, but do not want to replace the default `bc`. Defaults to empty. #### `EXECPREFIX` The prefix to append onto the executable names *when building and installing*. This is for packagers and distro maintainers who want this `bc` as an option, but do not want to replace the default `bc`. Defaults to empty. #### `LONG_BIT` The number of bits in a C `long` type. This is mostly for the embedded space. This `bc` uses `long`s internally for overflow checking. In C99, a `long` is required to be 32 bits. For this reason, on 8-bit and 16-bit microcontrollers, the generated code to do math with `long` types may be inefficient. For most normal desktop systems, setting this is unnecessary, except that 32-bit platforms with 64-bit longs may want to set it to `32`. Defaults to the default value of `LONG_BIT` for the target platform. For compliance with the `bc` spec, the minimum allowed value is `32`. It is an error if the specified value is greater than the default value of `LONG_BIT` for the target platform. #### `GEN_HOST` Whether to use `gen/strgen.c`, instead of `gen/strgen.sh`, to produce the C files that contain the help texts as well as the math libraries. By default, `gen/strgen.c` is used, compiled by `$HOSTCC` and run on the host machine. Using `gen/strgen.sh` removes the need to compile and run an executable on the host machine since `gen/strgen.sh` is a POSIX shell script. However, `gen/lib2.bc` is perilously close to 4095 characters, the max supported length of a string literal in C99 (and it could be added to in the future), and `gen/strgen.sh` generates a string literal instead of an array, as `gen/strgen.c` does. For most production-ready compilers, this limit probably is not enforced, but it could be. Both options are still available for this reason. If you are sure your compiler does not have the limit and do not want to compile and run a binary on the host machine, set this variable to "0". Any other value, or a non-existent value, will cause the build system to compile and run `gen/strgen.c`. Default is "". #### `GEN_EMU` The emulator to run bootstrap binaries under. This is only if the binaries produced by `HOSTCC` (or `HOST_CC`) need to be run under an emulator to work. Defaults to empty. ### Build Options This `bc` comes with several build options, all of which are enabled by default. All options can be used with each other, with a few exceptions that will be noted below. **NOTE**: All long options with mandatory argumenst accept either one of the following forms: ``` --option arg --option=arg ``` #### Library To build the math library, use the following commands for the configure step: ``` ./configure.sh -a ./configure.sh --library ``` Both commands are equivalent. When the library is built, history and locales are disabled, and the functionality for `bc` and `dc` are both enabled, though the executables are *not* built. This is because the library's options clash with the executables. To build an optimized version of the library, users can pass optimization options to `configure.sh` or include them in `CFLAGS`. The library API can be found in `manuals/bcl.3.md` or `man bcl` once the library is installed. The library is built as `bin/libbcl.a`. #### `bc` Only To build `bc` only (no `dc`), use any one of the following commands for the configure step: ``` ./configure.sh -b ./configure.sh --bc-only ./configure.sh -D ./configure.sh --disable-dc ``` Those commands are all equivalent. ***Warning***: It is an error to use those options if `bc` has also been disabled (see below). #### `dc` Only To build `dc` only (no `bc`), use either one of the following commands for the configure step: ``` ./configure.sh -d ./configure.sh --dc-only ./configure.sh -B ./configure.sh --disable-bc ``` Those commands are all equivalent. ***Warning***: It is an error to use those options if `dc` has also been disabled (see above). #### History To disable hisory, pass either the `-H` flag or the `--disable-history` option to `configure.sh`, as follows: ``` ./configure.sh -H ./configure.sh --disable-history ``` Both commands are equivalent. History is automatically disabled when building for Windows or on another platform that does not support the terminal handling that is required. ***WARNING***: Of all of the code in the `bc`, this is the only code that is not completely portable. If the `bc` does not work on your platform, your first step should be to retry with history disabled. This option affects the [build type][7]. #### NLS (Locale Support) To disable locale support (use only English), pass either the `-N` flag or the `--disable-nls` option to `configure.sh`, as follows: ``` ./configure.sh -N ./configure.sh --disable-nls ``` Both commands are equivalent. NLS (locale support) is automatically disabled when building for Windows or on another platform that does not support the POSIX locale API or utilities. This option affects the [build type][7]. #### Extra Math This `bc` has 7 extra operators: * `$` (truncation to integer) * `@` (set precision) * `@=` (set precision and assign) * `<<` (shift number left, shifts radix right) * `<<=` (shift number left and assign) * `>>` (shift number right, shifts radix left) * `>>=` (shift number right and assign) There is no assignment version of `$` because it is a unary operator. The assignment versions of the above operators are not available in `dc`, but the others are, as the operators `$`, `@`, `H`, and `h`, respectively. In addition, this `bc` has the option of outputting in scientific notation or engineering notation. It can also take input in scientific or engineering notation. On top of that, it has a pseudo-random number generator. (See the full manual for more details.) Extra operators, scientific notation, engineering notation, and the pseudo-random number generator can be disabled by passing either the `-E` flag or the `--disable-extra-math` option to `configure.sh`, as follows: ``` ./configure.sh -E ./configure.sh --disable-extra-math ``` Both commands are equivalent. This `bc` also has a larger library that is only enabled if extra operators and the pseudo-random number generator are. More information about the functions can be found in the Extended Library section of the full manual. This option affects the [build type][7]. #### Karatsuba Length The Karatsuba length is the point at which `bc` and `dc` switch from Karatsuba multiplication to brute force, `O(n^2)` multiplication. It can be set by passing the `-k` flag or the `--karatsuba-len` option to `configure.sh` as follows: ``` ./configure.sh -k32 ./configure.sh --karatsuba-len 32 ``` Both commands are equivalent. Default is `32`. ***WARNING***: The Karatsuba Length must be a **integer** greater than or equal to `16` (to prevent stack overflow). If it is not, `configure.sh` will give an error. #### Settings This `bc` and `dc` have a few settings to override default behavior. The defaults for these settings can be set by package maintainers, and the settings themselves can be overriden by users. To set a default to **on**, use the `-s` or `--set-default-on` option to `configure.sh`, with the name of the setting, as follows: ``` ./configure.sh -s bc.banner ./configure.sh --set-default-on=bc.banner ``` Both commands are equivalent. To set a default to **off**, use the `-S` or `--set-default-off` option to `configure.sh`, with the name of the setting, as follows: ``` ./configure.sh -S bc.banner ./configure.sh --set-default-off=bc.banner ``` Both commands are equivalent. Users can override the default settings set by packagers with environment variables. If the environment variable has an integer, then the setting is turned **on** for a non-zero integer, and **off** for zero. The table of the available settings, along with their defaults and the environment variables to override them, is below: ``` | Setting | Description | Default | Env Variable | | =============== | ==================== | ============ | ==================== | | bc.banner | Whether to display | 0 | BC_BANNER | | | the bc version | | | | | banner when in | | | | | interactive mode. | | | | --------------- | -------------------- | ------------ | -------------------- | | bc.sigint_reset | Whether SIGINT will | 1 | BC_SIGINT_RESET | | | reset bc, instead of | | | | | exiting, when in | | | | | interactive mode. | | | | --------------- | -------------------- | ------------ | -------------------- | | dc.sigint_reset | Whether SIGINT will | 1 | DC_SIGINT_RESET | | | reset dc, instead of | | | | | exiting, when in | | | | | interactive mode. | | | | --------------- | -------------------- | ------------ | -------------------- | | bc.tty_mode | Whether TTY mode for | 1 | BC_TTY_MODE | | | bc should be on when | | | | | available. | | | | --------------- | -------------------- | ------------ | -------------------- | | dc.tty_mode | Whether TTY mode for | 0 | BC_TTY_MODE | | | dc should be on when | | | | | available. | | | | --------------- | -------------------- | ------------ | -------------------- | | bc.prompt | Whether the prompt | $BC_TTY_MODE | BC_PROMPT | | | for bc should be on | | | | | in tty mode. | | | | --------------- | -------------------- | ------------ | -------------------- | | dc.prompt | Whether the prompt | $DC_TTY_MODE | DC_PROMPT | | | for dc should be on | | | | | in tty mode. | | | | --------------- | -------------------- | ------------ | -------------------- | ``` These settings are not meant to be changed on a whim. They are meant to ensure that this bc and dc will conform to the expectations of the user on each platform. #### Install Options The relevant `autotools`-style install options are supported in `configure.sh`: * `--prefix` * `--bindir` * `--datarootdir` * `--datadir` * `--mandir` * `--man1dir` * `--localedir` An example is: ``` ./configure.sh --prefix=/usr --localedir /usr/share/nls make make install ``` They correspond to the environment variables `$PREFIX`, `$BINDIR`, `$DATAROOTDIR`, `$DATADIR`, `$MANDIR`, `$MAN1DIR`, and `$LOCALEDIR`, respectively. ***WARNING***: If the option is given, the value of the corresponding environment variable is overridden. ***WARNING***: If any long command-line options are used, the long form of all other command-line options must be used. Mixing long and short options is not supported. ##### Manpages To disable installing manpages, pass either the `-M` flag or the `--disable-man-pages` option to `configure.sh` as follows: ``` ./configure.sh -M ./configure.sh --disable-man-pages ``` Both commands are equivalent. ##### Locales By default, `bc` and `dc` do not install all locales, but only the enabled locales. If `DESTDIR` exists and is not empty, then they will install all of the locales that exist on the system. The `-l` flag or `--install-all-locales` option skips all of that and just installs all of the locales that `bc` and `dc` have, regardless. To enable that behavior, you can pass the `-l` flag or the `--install-all-locales` option to `configure.sh`, as follows: ``` ./configure.sh -l ./configure.sh --install-all-locales ``` Both commands are equivalent. ### Optimization The `configure.sh` script will accept an optimization level to pass to the compiler. Because `bc` is orders of magnitude faster with optimization, I ***highly*** recommend package and distro maintainers pass the highest optimization level available in `CC` to `configure.sh` with the `-O` flag or `--opt` option, as follows: ``` ./configure.sh -O3 ./configure.sh --opt 3 ``` Both commands are equivalent. The build and install can then be run as normal: ``` make make install ``` As usual, `configure.sh` will also accept additional `CFLAGS` on the command line, so for SSE4 architectures, the following can add a bit more speed: ``` CFLAGS="-march=native -msse4" ./configure.sh -O3 make make install ``` Building with link-time optimization (`-flto` in clang) can further increase the performance. I ***highly*** recommend doing so. I do ***NOT*** recommend building with `-march=native`; doing so reduces this `bc`'s performance. Manual stripping is not necessary; non-debug builds are automatically stripped in the link stage. ### Debug Builds Debug builds (which also disable optimization if no optimization level is given and if no extra `CFLAGS` are given) can be enabled with either the `-g` flag or the `--debug` option, as follows: ``` ./configure.sh -g ./configure.sh --debug ``` Both commands are equivalent. The build and install can then be run as normal: ``` make make install ``` ### Stripping Binaries By default, when `bc` and `dc` are not built in debug mode, the binaries are stripped. Stripping can be disabled with either the `-T` or the `--disable-strip` option, as follows: ``` ./configure.sh -T ./configure.sh --disable-strip ``` Both commands are equivalent. The build and install can then be run as normal: ``` make make install ``` ### Build Type `bc` and `dc` have 8 build types, affected by the [History][8], [NLS (Locale Support)][9], and [Extra Math][10] build options. The build types are as follows: * `A`: Nothing disabled. * `E`: Extra math disabled. * `H`: History disabled. * `N`: NLS disabled. * `EH`: Extra math and History disabled. * `EN`: Extra math and NLS disabled. * `HN`: History and NLS disabled. * `EHN`: Extra math, History, and NLS all disabled. These build types correspond to the generated manuals in `manuals/bc` and `manuals/dc`. ### Binary Size When built with both calculators, all available features, and `-Os` using `clang` and `musl`, the executable is 140.4 kb (140,386 bytes) on `x86_64`. That isn't much for what is contained in the binary, but if necessary, it can be reduced. The single largest user of space is the `bc` calculator. If just `dc` is needed, the size can be reduced to 107.6 kb (107,584 bytes). The next largest user of space is history support. If that is not needed, size can be reduced (for a build with both calculators) to 119.9 kb (119,866 bytes). There are several reasons that history is a bigger user of space than `dc` itself: * `dc`'s lexer and parser are *tiny* compared to `bc`'s because `dc` code is almost already in the form that it is executed in, while `bc` has to not only adjust the form to be executable, it has to parse functions, loops, `if` statements, and other extra features. * `dc` does not have much extra code in the interpreter. * History has a lot of const data for supporting `UTF-8` terminals. * History pulls in a bunch of more code from the `libc`. The next biggest user is extra math support. Without it, the size is reduced to 124.0 kb (123,986 bytes) with history and 107.6 kb (107,560 bytes) without history. The reasons why extra math support is bigger than `dc`, besides the fact that `dc` is small already, are: * Extra math supports adds an extra math library that takes several kilobytes of constant data space. * Extra math support includes support for a pseudo-random number generator, including the code to convert a series of pseudo-random numbers into a number of arbitrary size. * Extra math support adds several operators. The next biggest user is `dc`, so if just `bc` is needed, the size can be reduced to 128.1 kb (128,096 bytes) with history and extra math support, 107.6 kb (107,576 bytes) without history and with extra math support, and 95.3 kb (95,272 bytes) without history and without extra math support. *Note*: all of these binary sizes were compiled using `musl` `1.2.0` as the `libc`, making a fully static executable, with `clang` `9.0.1` (well, `musl-clang` using `clang` `9.0.1`) as the compiler and using `-Os` optimizations. These builds were done on an `x86_64` machine running Gentoo Linux. ### Testing The default test suite can be run with the following command: ``` make test ``` To test `bc` only, run the following command: ``` make test_bc ``` To test `dc` only, run the following command: ``` make test_dc ``` This `bc`, if built, assumes a working, GNU-compatible `bc`, installed on the system and in the `PATH`, to generate some tests, unless the `-G` flag or `--disable-generated-tests` option is given to `configure.sh`, as follows: ``` ./configure.sh -G ./configure.sh --disable-generated-tests ``` After running `configure.sh`, build and run tests as follows: ``` make make test ``` This `dc` also assumes a working, GNU-compatible `dc`, installed on the system and in the `PATH`, to generate some tests, unless one of the above options is given to `configure.sh`. To generate test coverage, pass the `-c` flag or the `--coverage` option to `configure.sh` as follows: ``` ./configure.sh -c ./configure.sh --coverage ``` Both commands are equivalent. ***WARNING***: Both `bc` and `dc` must be built for test coverage. Otherwise, `configure.sh` will give an error. [1]: https://pubs.opengroup.org/onlinepubs/9699919799/utilities/bc.html [2]: https://www.gnu.org/software/bc/ [3]: https://www.musl-libc.org/ [4]: #build-environment-variables [5]: #build-options [6]: #cross-compiling [7]: #build-type [8]: #history [9]: #nls-locale-support [10]: #extra-math [11]: #settings diff --git a/contrib/bc/manuals/dc/A.1 b/contrib/bc/manuals/dc/A.1 index a7ff2e3a6963..3dff3b16d080 100644 --- a/contrib/bc/manuals/dc/A.1 +++ b/contrib/bc/manuals/dc/A.1 @@ -1,1549 +1,1562 @@ .\" .\" SPDX-License-Identifier: BSD-2-Clause .\" .\" Copyright (c) 2018-2021 Gavin D. Howard and contributors. .\" .\" Redistribution and use in source and binary forms, with or without .\" modification, are permitted provided that the following conditions are met: .\" .\" * Redistributions of source code must retain the above copyright notice, .\" this list of conditions and the following disclaimer. .\" .\" * Redistributions in binary form must reproduce the above copyright notice, .\" this list of conditions and the following disclaimer in the documentation .\" and/or other materials provided with the distribution. .\" .\" THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" .\" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE .\" IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE .\" ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE .\" LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR .\" CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF .\" SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS .\" INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN .\" CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) .\" ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE .\" POSSIBILITY OF SUCH DAMAGE. .\" .TH "DC" "1" "June 2021" "Gavin D. Howard" "General Commands Manual" .SH Name .PP dc - arbitrary-precision decimal reverse-Polish notation calculator .SH SYNOPSIS .PP \f[B]dc\f[R] [\f[B]-hiPRvVx\f[R]] [\f[B]--version\f[R]] [\f[B]--help\f[R]] [\f[B]--interactive\f[R]] [\f[B]--no-prompt\f[R]] [\f[B]--no-read-prompt\f[R]] [\f[B]--extended-register\f[R]] [\f[B]-e\f[R] \f[I]expr\f[R]] [\f[B]--expression\f[R]=\f[I]expr\f[R]\&...] [\f[B]-f\f[R] \f[I]file\f[R]\&...] [\f[B]--file\f[R]=\f[I]file\f[R]\&...] [\f[I]file\f[R]\&...] .SH DESCRIPTION .PP dc(1) is an arbitrary-precision calculator. It uses a stack (reverse Polish notation) to store numbers and results of computations. Arithmetic operations pop arguments off of the stack and push the results. .PP If no files are given on the command-line, then dc(1) reads from \f[B]stdin\f[R] (see the \f[B]STDIN\f[R] section). Otherwise, those files are processed, and dc(1) will then exit. .PP If a user wants to set up a standard environment, they can use \f[B]DC_ENV_ARGS\f[R] (see the \f[B]ENVIRONMENT VARIABLES\f[R] section). For example, if a user wants the \f[B]scale\f[R] always set to \f[B]10\f[R], they can set \f[B]DC_ENV_ARGS\f[R] to \f[B]-e 10k\f[R], and this dc(1) will always start with a \f[B]scale\f[R] of \f[B]10\f[R]. .SH OPTIONS .PP The following are the options that dc(1) accepts. .TP \f[B]-h\f[R], \f[B]--help\f[R] Prints a usage message and quits. .TP \f[B]-v\f[R], \f[B]-V\f[R], \f[B]--version\f[R] Print the version information (copyright header) and exit. .TP \f[B]-i\f[R], \f[B]--interactive\f[R] Forces interactive mode. (See the \f[B]INTERACTIVE MODE\f[R] section.) .RS .PP This is a \f[B]non-portable extension\f[R]. .RE .TP \f[B]-L\f[R], \f[B]--no-line-length\f[R] Disables line length checking and prints numbers without backslashes and newlines. In other words, this option sets \f[B]BC_LINE_LENGTH\f[R] to \f[B]0\f[R] (see the \f[B]ENVIRONMENT VARIABLES\f[R] section). .RS .PP This is a \f[B]non-portable extension\f[R]. .RE .TP \f[B]-P\f[R], \f[B]--no-prompt\f[R] Disables the prompt in TTY mode. (The prompt is only enabled in TTY mode. See the \f[B]TTY MODE\f[R] section.) This is mostly for those users that do not want a prompt or are not used to having them in dc(1). Most of those users would want to put this option in \f[B]DC_ENV_ARGS\f[R]. .RS .PP These options override the \f[B]DC_PROMPT\f[R] and \f[B]DC_TTY_MODE\f[R] environment variables (see the \f[B]ENVIRONMENT VARIABLES\f[R] section). .PP This is a \f[B]non-portable extension\f[R]. .RE .TP \f[B]-R\f[R], \f[B]--no-read-prompt\f[R] Disables the read prompt in TTY mode. (The read prompt is only enabled in TTY mode. See the \f[B]TTY MODE\f[R] section.) This is mostly for those users that do not want a read prompt or are not used to having them in dc(1). Most of those users would want to put this option in \f[B]BC_ENV_ARGS\f[R] (see the \f[B]ENVIRONMENT VARIABLES\f[R] section). This option is also useful in hash bang lines of dc(1) scripts that prompt for user input. .RS .PP This option does not disable the regular prompt because the read prompt is only used when the \f[B]?\f[R] command is used. .PP These options \f[I]do\f[R] override the \f[B]DC_PROMPT\f[R] and \f[B]DC_TTY_MODE\f[R] environment variables (see the \f[B]ENVIRONMENT VARIABLES\f[R] section), but only for the read prompt. .PP This is a \f[B]non-portable extension\f[R]. .RE .TP \f[B]-x\f[R] \f[B]--extended-register\f[R] Enables extended register mode. See the \f[I]Extended Register Mode\f[R] subsection of the \f[B]REGISTERS\f[R] section for more information. .RS .PP This is a \f[B]non-portable extension\f[R]. .RE .TP \f[B]-z\f[R], \f[B]--leading-zeroes\f[R] Makes bc(1) print all numbers greater than \f[B]-1\f[R] and less than \f[B]1\f[R], and not equal to \f[B]0\f[R], with a leading zero. .RS .PP This can be set for individual numbers with the \f[B]plz(x)\f[R], plznl(x)**, \f[B]pnlz(x)\f[R], and \f[B]pnlznl(x)\f[R] functions in the extended math library (see the \f[B]LIBRARY\f[R] section). .PP This is a \f[B]non-portable extension\f[R]. .RE .TP \f[B]-e\f[R] \f[I]expr\f[R], \f[B]--expression\f[R]=\f[I]expr\f[R] Evaluates \f[I]expr\f[R]. If multiple expressions are given, they are evaluated in order. If files are given as well (see below), the expressions and files are evaluated in the order given. This means that if a file is given before an expression, the file is read in and evaluated first. .RS .PP If this option is given on the command-line (i.e., not in \f[B]DC_ENV_ARGS\f[R], see the \f[B]ENVIRONMENT VARIABLES\f[R] section), then after processing all expressions and files, dc(1) will exit, unless \f[B]-\f[R] (\f[B]stdin\f[R]) was given as an argument at least once to \f[B]-f\f[R] or \f[B]--file\f[R], whether on the command-line or in \f[B]DC_ENV_ARGS\f[R]. However, if any other \f[B]-e\f[R], \f[B]--expression\f[R], \f[B]-f\f[R], or \f[B]--file\f[R] arguments are given after \f[B]-f-\f[R] or equivalent is given, dc(1) will give a fatal error and exit. .PP This is a \f[B]non-portable extension\f[R]. .RE .TP \f[B]-f\f[R] \f[I]file\f[R], \f[B]--file\f[R]=\f[I]file\f[R] Reads in \f[I]file\f[R] and evaluates it, line by line, as though it were read through \f[B]stdin\f[R]. If expressions are also given (see above), the expressions are evaluated in the order given. .RS .PP If this option is given on the command-line (i.e., not in \f[B]DC_ENV_ARGS\f[R], see the \f[B]ENVIRONMENT VARIABLES\f[R] section), then after processing all expressions and files, dc(1) will exit, unless \f[B]-\f[R] (\f[B]stdin\f[R]) was given as an argument at least once to \f[B]-f\f[R] or \f[B]--file\f[R]. However, if any other \f[B]-e\f[R], \f[B]--expression\f[R], \f[B]-f\f[R], or \f[B]--file\f[R] arguments are given after \f[B]-f-\f[R] or equivalent is given, dc(1) will give a fatal error and exit. .PP This is a \f[B]non-portable extension\f[R]. .RE .PP All long options are \f[B]non-portable extensions\f[R]. .SH STDIN .PP If no files are given on the command-line and no files or expressions are given by the \f[B]-f\f[R], \f[B]--file\f[R], \f[B]-e\f[R], or \f[B]--expression\f[R] options, then dc(1) read from \f[B]stdin\f[R]. .PP However, there is a caveat to this. .PP First, \f[B]stdin\f[R] is evaluated a line at a time. The only exception to this is if a string has been finished, but not ended. This means that, except for escaped brackets, all brackets must be balanced before dc(1) parses and executes. .SH STDOUT .PP Any non-error output is written to \f[B]stdout\f[R]. In addition, if history (see the \f[B]HISTORY\f[R] section) and the prompt (see the \f[B]TTY MODE\f[R] section) are enabled, both are output to \f[B]stdout\f[R]. .PP \f[B]Note\f[R]: Unlike other dc(1) implementations, this dc(1) will issue a fatal error (see the \f[B]EXIT STATUS\f[R] section) if it cannot write to \f[B]stdout\f[R], so if \f[B]stdout\f[R] is closed, as in \f[B]dc >&-\f[R], it will quit with an error. This is done so that dc(1) can report problems when \f[B]stdout\f[R] is redirected to a file. .PP If there are scripts that depend on the behavior of other dc(1) implementations, it is recommended that those scripts be changed to redirect \f[B]stdout\f[R] to \f[B]/dev/null\f[R]. .SH STDERR .PP Any error output is written to \f[B]stderr\f[R]. .PP \f[B]Note\f[R]: Unlike other dc(1) implementations, this dc(1) will issue a fatal error (see the \f[B]EXIT STATUS\f[R] section) if it cannot write to \f[B]stderr\f[R], so if \f[B]stderr\f[R] is closed, as in \f[B]dc 2>&-\f[R], it will quit with an error. This is done so that dc(1) can exit with an error code when \f[B]stderr\f[R] is redirected to a file. .PP If there are scripts that depend on the behavior of other dc(1) implementations, it is recommended that those scripts be changed to redirect \f[B]stderr\f[R] to \f[B]/dev/null\f[R]. .SH SYNTAX .PP Each item in the input source code, either a number (see the \f[B]NUMBERS\f[R] section) or a command (see the \f[B]COMMANDS\f[R] section), is processed and executed, in order. Input is processed immediately when entered. .PP \f[B]ibase\f[R] is a register (see the \f[B]REGISTERS\f[R] section) that determines how to interpret constant numbers. It is the \[lq]input\[rq] base, or the number base used for interpreting input numbers. \f[B]ibase\f[R] is initially \f[B]10\f[R]. The max allowable value for \f[B]ibase\f[R] is \f[B]16\f[R]. The min allowable value for \f[B]ibase\f[R] is \f[B]2\f[R]. The max allowable value for \f[B]ibase\f[R] can be queried in dc(1) programs with the \f[B]T\f[R] command. .PP \f[B]obase\f[R] is a register (see the \f[B]REGISTERS\f[R] section) that determines how to output results. It is the \[lq]output\[rq] base, or the number base used for outputting numbers. \f[B]obase\f[R] is initially \f[B]10\f[R]. The max allowable value for \f[B]obase\f[R] is \f[B]DC_BASE_MAX\f[R] and can be queried with the \f[B]U\f[R] command. The min allowable value for \f[B]obase\f[R] is \f[B]0\f[R]. If \f[B]obase\f[R] is \f[B]0\f[R], values are output in scientific notation, and if \f[B]obase\f[R] is \f[B]1\f[R], values are output in engineering notation. Otherwise, values are output in the specified base. .PP Outputting in scientific and engineering notations are \f[B]non-portable extensions\f[R]. .PP The \f[I]scale\f[R] of an expression is the number of digits in the result of the expression right of the decimal point, and \f[B]scale\f[R] is a register (see the \f[B]REGISTERS\f[R] section) that sets the precision of any operations (with exceptions). \f[B]scale\f[R] is initially \f[B]0\f[R]. \f[B]scale\f[R] cannot be negative. The max allowable value for \f[B]scale\f[R] can be queried in dc(1) programs with the \f[B]V\f[R] command. .PP \f[B]seed\f[R] is a register containing the current seed for the pseudo-random number generator. If the current value of \f[B]seed\f[R] is queried and stored, then if it is assigned to \f[B]seed\f[R] later, the pseudo-random number generator is guaranteed to produce the same sequence of pseudo-random numbers that were generated after the value of \f[B]seed\f[R] was first queried. .PP Multiple values assigned to \f[B]seed\f[R] can produce the same sequence of pseudo-random numbers. Likewise, when a value is assigned to \f[B]seed\f[R], it is not guaranteed that querying \f[B]seed\f[R] immediately after will return the same value. In addition, the value of \f[B]seed\f[R] will change after any call to the \f[B]\[cq]\f[R] command or the \f[B]\[lq]\f[R] command that does not get receive a value of \f[B]0\f[R] or \f[B]1\f[R]. The maximum integer returned by the \f[B]\[cq]\f[R] command can be queried with the \f[B]W\f[R] command. .PP \f[B]Note\f[R]: The values returned by the pseudo-random number generator with the \f[B]\[cq]\f[R] and \f[B]\[lq]\f[R] commands are guaranteed to \f[B]NOT\f[R] be cryptographically secure. This is a consequence of using a seeded pseudo-random number generator. However, they \f[I]are\f[R] guaranteed to be reproducible with identical \f[B]seed\f[R] values. This means that the pseudo-random values from dc(1) should only be used where a reproducible stream of pseudo-random numbers is \f[I]ESSENTIAL\f[R]. In any other case, use a non-seeded pseudo-random number generator. .PP The pseudo-random number generator, \f[B]seed\f[R], and all associated operations are \f[B]non-portable extensions\f[R]. .SS Comments .PP Comments go from \f[B]#\f[R] until, and not including, the next newline. This is a \f[B]non-portable extension\f[R]. .SH NUMBERS .PP Numbers are strings made up of digits, uppercase letters up to \f[B]F\f[R], and at most \f[B]1\f[R] period for a radix. Numbers can have up to \f[B]DC_NUM_MAX\f[R] digits. Uppercase letters are equal to \f[B]9\f[R] + their position in the alphabet (i.e., \f[B]A\f[R] equals \f[B]10\f[R], or \f[B]9+1\f[R]). If a digit or letter makes no sense with the current value of \f[B]ibase\f[R], they are set to the value of the highest valid digit in \f[B]ibase\f[R]. .PP Single-character numbers (i.e., \f[B]A\f[R] alone) take the value that they would have if they were valid digits, regardless of the value of \f[B]ibase\f[R]. This means that \f[B]A\f[R] alone always equals decimal \f[B]10\f[R] and \f[B]F\f[R] alone always equals decimal \f[B]15\f[R]. .PP In addition, dc(1) accepts numbers in scientific notation. These have the form \f[B]e\f[R]. The exponent (the portion after the \f[B]e\f[R]) must be an integer. An example is \f[B]1.89237e9\f[R], which is equal to \f[B]1892370000\f[R]. Negative exponents are also allowed, so \f[B]4.2890e_3\f[R] is equal to \f[B]0.0042890\f[R]. .PP \f[B]WARNING\f[R]: Both the number and the exponent in scientific notation are interpreted according to the current \f[B]ibase\f[R], but the number is still multiplied by \f[B]10\[ha]exponent\f[R] regardless of the current \f[B]ibase\f[R]. For example, if \f[B]ibase\f[R] is \f[B]16\f[R] and dc(1) is given the number string \f[B]FFeA\f[R], the resulting decimal number will be \f[B]2550000000000\f[R], and if dc(1) is given the number string \f[B]10e_4\f[R], the resulting decimal number will be \f[B]0.0016\f[R]. .PP Accepting input as scientific notation is a \f[B]non-portable extension\f[R]. .SH COMMANDS .PP The valid commands are listed below. .SS Printing .PP These commands are used for printing. .PP Note that both scientific notation and engineering notation are available for printing numbers. Scientific notation is activated by assigning \f[B]0\f[R] to \f[B]obase\f[R] using \f[B]0o\f[R], and engineering notation is activated by assigning \f[B]1\f[R] to \f[B]obase\f[R] using \f[B]1o\f[R]. To deactivate them, just assign a different value to \f[B]obase\f[R]. .PP Printing numbers in scientific notation and/or engineering notation is a \f[B]non-portable extension\f[R]. .TP \f[B]p\f[R] Prints the value on top of the stack, whether number or string, and prints a newline after. .RS .PP This does not alter the stack. .RE .TP \f[B]n\f[R] Prints the value on top of the stack, whether number or string, and pops it off of the stack. .TP \f[B]P\f[R] Pops a value off the stack. .RS .PP If the value is a number, it is truncated and the absolute value of the result is printed as though \f[B]obase\f[R] is \f[B]256\f[R] and each digit is interpreted as an 8-bit ASCII character, making it a byte stream. .PP If the value is a string, it is printed without a trailing newline. .PP This is a \f[B]non-portable extension\f[R]. .RE .TP \f[B]f\f[R] Prints the entire contents of the stack, in order from newest to oldest, without altering anything. .RS .PP Users should use this command when they get lost. .RE .SS Arithmetic .PP These are the commands used for arithmetic. .TP \f[B]+\f[R] The top two values are popped off the stack, added, and the result is pushed onto the stack. The \f[I]scale\f[R] of the result is equal to the max \f[I]scale\f[R] of both operands. .TP \f[B]-\f[R] The top two values are popped off the stack, subtracted, and the result is pushed onto the stack. The \f[I]scale\f[R] of the result is equal to the max \f[I]scale\f[R] of both operands. .TP \f[B]*\f[R] The top two values are popped off the stack, multiplied, and the result is pushed onto the stack. If \f[B]a\f[R] is the \f[I]scale\f[R] of the first expression and \f[B]b\f[R] is the \f[I]scale\f[R] of the second expression, the \f[I]scale\f[R] of the result is equal to \f[B]min(a+b,max(scale,a,b))\f[R] where \f[B]min()\f[R] and \f[B]max()\f[R] return the obvious values. .TP \f[B]/\f[R] The top two values are popped off the stack, divided, and the result is pushed onto the stack. The \f[I]scale\f[R] of the result is equal to \f[B]scale\f[R]. .RS .PP The first value popped off of the stack must be non-zero. .RE .TP \f[B]%\f[R] The top two values are popped off the stack, remaindered, and the result is pushed onto the stack. .RS .PP Remaindering is equivalent to 1) Computing \f[B]a/b\f[R] to current \f[B]scale\f[R], and 2) Using the result of step 1 to calculate \f[B]a-(a/b)*b\f[R] to \f[I]scale\f[R] \f[B]max(scale+scale(b),scale(a))\f[R]. .PP The first value popped off of the stack must be non-zero. .RE .TP \f[B]\[ti]\f[R] The top two values are popped off the stack, divided and remaindered, and the results (divided first, remainder second) are pushed onto the stack. This is equivalent to \f[B]x y / x y %\f[R] except that \f[B]x\f[R] and \f[B]y\f[R] are only evaluated once. .RS .PP The first value popped off of the stack must be non-zero. .PP This is a \f[B]non-portable extension\f[R]. .RE .TP \f[B]\[ha]\f[R] The top two values are popped off the stack, the second is raised to the power of the first, and the result is pushed onto the stack. The \f[I]scale\f[R] of the result is equal to \f[B]scale\f[R]. .RS .PP The first value popped off of the stack must be an integer, and if that value is negative, the second value popped off of the stack must be non-zero. .RE .TP \f[B]v\f[R] The top value is popped off the stack, its square root is computed, and the result is pushed onto the stack. The \f[I]scale\f[R] of the result is equal to \f[B]scale\f[R]. .RS .PP The value popped off of the stack must be non-negative. .RE .TP \f[B]_\f[R] If this command \f[I]immediately\f[R] precedes a number (i.e., no spaces or other commands), then that number is input as a negative number. .RS .PP Otherwise, the top value on the stack is popped and copied, and the copy is negated and pushed onto the stack. This behavior without a number is a \f[B]non-portable extension\f[R]. .RE .TP \f[B]b\f[R] The top value is popped off the stack, and if it is zero, it is pushed back onto the stack. Otherwise, its absolute value is pushed onto the stack. .RS .PP This is a \f[B]non-portable extension\f[R]. .RE .TP \f[B]|\f[R] The top three values are popped off the stack, a modular exponentiation is computed, and the result is pushed onto the stack. .RS .PP The first value popped is used as the reduction modulus and must be an integer and non-zero. The second value popped is used as the exponent and must be an integer and non-negative. The third value popped is the base and must be an integer. .PP This is a \f[B]non-portable extension\f[R]. .RE .TP \f[B]$\f[R] The top value is popped off the stack and copied, and the copy is truncated and pushed onto the stack. .RS .PP This is a \f[B]non-portable extension\f[R]. .RE .TP \f[B]\[at]\f[R] The top two values are popped off the stack, and the precision of the second is set to the value of the first, whether by truncation or extension. .RS .PP The first value popped off of the stack must be an integer and non-negative. .PP This is a \f[B]non-portable extension\f[R]. .RE .TP \f[B]H\f[R] The top two values are popped off the stack, and the second is shifted left (radix shifted right) to the value of the first. .RS .PP The first value popped off of the stack must be an integer and non-negative. .PP This is a \f[B]non-portable extension\f[R]. .RE .TP \f[B]h\f[R] The top two values are popped off the stack, and the second is shifted right (radix shifted left) to the value of the first. .RS .PP The first value popped off of the stack must be an integer and non-negative. .PP This is a \f[B]non-portable extension\f[R]. .RE .TP \f[B]G\f[R] The top two values are popped off of the stack, they are compared, and a \f[B]1\f[R] is pushed if they are equal, or \f[B]0\f[R] otherwise. .RS .PP This is a \f[B]non-portable extension\f[R]. .RE .TP \f[B]N\f[R] The top value is popped off of the stack, and if it a \f[B]0\f[R], a \f[B]1\f[R] is pushed; otherwise, a \f[B]0\f[R] is pushed. .RS .PP This is a \f[B]non-portable extension\f[R]. .RE .TP \f[B](\f[R] The top two values are popped off of the stack, they are compared, and a \f[B]1\f[R] is pushed if the first is less than the second, or \f[B]0\f[R] otherwise. .RS .PP This is a \f[B]non-portable extension\f[R]. .RE .TP \f[B]{\f[R] The top two values are popped off of the stack, they are compared, and a \f[B]1\f[R] is pushed if the first is less than or equal to the second, or \f[B]0\f[R] otherwise. .RS .PP This is a \f[B]non-portable extension\f[R]. .RE .TP \f[B])\f[R] The top two values are popped off of the stack, they are compared, and a \f[B]1\f[R] is pushed if the first is greater than the second, or \f[B]0\f[R] otherwise. .RS .PP This is a \f[B]non-portable extension\f[R]. .RE .TP \f[B]}\f[R] The top two values are popped off of the stack, they are compared, and a \f[B]1\f[R] is pushed if the first is greater than or equal to the second, or \f[B]0\f[R] otherwise. .RS .PP This is a \f[B]non-portable extension\f[R]. .RE .TP \f[B]M\f[R] The top two values are popped off of the stack. If they are both non-zero, a \f[B]1\f[R] is pushed onto the stack. If either of them is zero, or both of them are, then a \f[B]0\f[R] is pushed onto the stack. .RS .PP This is like the \f[B]&&\f[R] operator in bc(1), and it is \f[I]not\f[R] a short-circuit operator. .PP This is a \f[B]non-portable extension\f[R]. .RE .TP \f[B]m\f[R] The top two values are popped off of the stack. If at least one of them is non-zero, a \f[B]1\f[R] is pushed onto the stack. If both of them are zero, then a \f[B]0\f[R] is pushed onto the stack. .RS .PP This is like the \f[B]||\f[R] operator in bc(1), and it is \f[I]not\f[R] a short-circuit operator. .PP This is a \f[B]non-portable extension\f[R]. .RE .SS Pseudo-Random Number Generator .PP dc(1) has a built-in pseudo-random number generator. These commands query the pseudo-random number generator. (See Parameters for more information about the \f[B]seed\f[R] value that controls the pseudo-random number generator.) .PP The pseudo-random number generator is guaranteed to \f[B]NOT\f[R] be cryptographically secure. .TP \f[B]\[cq]\f[R] Generates an integer between 0 and \f[B]DC_RAND_MAX\f[R], inclusive (see the \f[B]LIMITS\f[R] section). .RS .PP The generated integer is made as unbiased as possible, subject to the limitations of the pseudo-random number generator. .PP This is a \f[B]non-portable extension\f[R]. .RE .TP \f[B]\[lq]\f[R] Pops a value off of the stack, which is used as an \f[B]exclusive\f[R] upper bound on the integer that will be generated. If the bound is negative or is a non-integer, an error is raised, and dc(1) resets (see the \f[B]RESET\f[R] section) while \f[B]seed\f[R] remains unchanged. If the bound is larger than \f[B]DC_RAND_MAX\f[R], the higher bound is honored by generating several pseudo-random integers, multiplying them by appropriate powers of \f[B]DC_RAND_MAX+1\f[R], and adding them together. Thus, the size of integer that can be generated with this command is unbounded. Using this command will change the value of \f[B]seed\f[R], unless the operand is \f[B]0\f[R] or \f[B]1\f[R]. In that case, \f[B]0\f[R] is pushed onto the stack, and \f[B]seed\f[R] is \f[I]not\f[R] changed. .RS .PP The generated integer is made as unbiased as possible, subject to the limitations of the pseudo-random number generator. .PP This is a \f[B]non-portable extension\f[R]. .RE .SS Stack Control .PP These commands control the stack. .TP \f[B]c\f[R] Removes all items from (\[lq]clears\[rq]) the stack. .TP \f[B]d\f[R] Copies the item on top of the stack (\[lq]duplicates\[rq]) and pushes the copy onto the stack. .TP \f[B]r\f[R] Swaps (\[lq]reverses\[rq]) the two top items on the stack. .TP \f[B]R\f[R] Pops (\[lq]removes\[rq]) the top value from the stack. .SS Register Control .PP These commands control registers (see the \f[B]REGISTERS\f[R] section). .TP \f[B]s\f[R]\f[I]r\f[R] Pops the value off the top of the stack and stores it into register \f[I]r\f[R]. .TP \f[B]l\f[R]\f[I]r\f[R] Copies the value in register \f[I]r\f[R] and pushes it onto the stack. This does not alter the contents of \f[I]r\f[R]. .TP \f[B]S\f[R]\f[I]r\f[R] Pops the value off the top of the (main) stack and pushes it onto the stack of register \f[I]r\f[R]. The previous value of the register becomes inaccessible. .TP \f[B]L\f[R]\f[I]r\f[R] Pops the value off the top of the stack for register \f[I]r\f[R] and push it onto the main stack. The previous value in the stack for register \f[I]r\f[R], if any, is now accessible via the \f[B]l\f[R]\f[I]r\f[R] command. .SS Parameters .PP These commands control the values of \f[B]ibase\f[R], \f[B]obase\f[R], \f[B]scale\f[R], and \f[B]seed\f[R]. Also see the \f[B]SYNTAX\f[R] section. .TP \f[B]i\f[R] Pops the value off of the top of the stack and uses it to set \f[B]ibase\f[R], which must be between \f[B]2\f[R] and \f[B]16\f[R], inclusive. .RS .PP If the value on top of the stack has any \f[I]scale\f[R], the \f[I]scale\f[R] is ignored. .RE .TP \f[B]o\f[R] Pops the value off of the top of the stack and uses it to set \f[B]obase\f[R], which must be between \f[B]0\f[R] and \f[B]DC_BASE_MAX\f[R], inclusive (see the \f[B]LIMITS\f[R] section and the \f[B]NUMBERS\f[R] section). .RS .PP If the value on top of the stack has any \f[I]scale\f[R], the \f[I]scale\f[R] is ignored. .RE .TP \f[B]k\f[R] Pops the value off of the top of the stack and uses it to set \f[B]scale\f[R], which must be non-negative. .RS .PP If the value on top of the stack has any \f[I]scale\f[R], the \f[I]scale\f[R] is ignored. .RE .TP \f[B]j\f[R] Pops the value off of the top of the stack and uses it to set \f[B]seed\f[R]. The meaning of \f[B]seed\f[R] is dependent on the current pseudo-random number generator but is guaranteed to not change except for new major versions. .RS .PP The \f[I]scale\f[R] and sign of the value may be significant. .PP If a previously used \f[B]seed\f[R] value is used again, the pseudo-random number generator is guaranteed to produce the same sequence of pseudo-random numbers as it did when the \f[B]seed\f[R] value was previously used. .PP The exact value assigned to \f[B]seed\f[R] is not guaranteed to be returned if the \f[B]J\f[R] command is used. However, if \f[B]seed\f[R] \f[I]does\f[R] return a different value, both values, when assigned to \f[B]seed\f[R], are guaranteed to produce the same sequence of pseudo-random numbers. This means that certain values assigned to \f[B]seed\f[R] will not produce unique sequences of pseudo-random numbers. .PP There is no limit to the length (number of significant decimal digits) or \f[I]scale\f[R] of the value that can be assigned to \f[B]seed\f[R]. .PP This is a \f[B]non-portable extension\f[R]. .RE .TP \f[B]I\f[R] Pushes the current value of \f[B]ibase\f[R] onto the main stack. .TP \f[B]O\f[R] Pushes the current value of \f[B]obase\f[R] onto the main stack. .TP \f[B]K\f[R] Pushes the current value of \f[B]scale\f[R] onto the main stack. .TP \f[B]J\f[R] Pushes the current value of \f[B]seed\f[R] onto the main stack. .RS .PP This is a \f[B]non-portable extension\f[R]. .RE .TP \f[B]T\f[R] Pushes the maximum allowable value of \f[B]ibase\f[R] onto the main stack. .RS .PP This is a \f[B]non-portable extension\f[R]. .RE .TP \f[B]U\f[R] Pushes the maximum allowable value of \f[B]obase\f[R] onto the main stack. .RS .PP This is a \f[B]non-portable extension\f[R]. .RE .TP \f[B]V\f[R] Pushes the maximum allowable value of \f[B]scale\f[R] onto the main stack. .RS .PP This is a \f[B]non-portable extension\f[R]. .RE .TP \f[B]W\f[R] Pushes the maximum (inclusive) integer that can be generated with the \f[B]\[cq]\f[R] pseudo-random number generator command. .RS .PP This is a \f[B]non-portable extension\f[R]. .RE .SS Strings .PP The following commands control strings. .PP dc(1) can work with both numbers and strings, and registers (see the \f[B]REGISTERS\f[R] section) can hold both strings and numbers. dc(1) always knows whether the contents of a register are a string or a number. .PP While arithmetic operations have to have numbers, and will print an error if given a string, other commands accept strings. .PP Strings can also be executed as macros. For example, if the string \f[B][1pR]\f[R] is executed as a macro, then the code \f[B]1pR\f[R] is executed, meaning that the \f[B]1\f[R] will be printed with a newline after and then popped from the stack. .TP \f[B][\f[R]\f[I]characters\f[R]\f[B]]\f[R] Makes a string containing \f[I]characters\f[R] and pushes it onto the stack. .RS .PP If there are brackets (\f[B][\f[R] and \f[B]]\f[R]) in the string, then they must be balanced. Unbalanced brackets can be escaped using a backslash (\f[B]\[rs]\f[R]) character. .PP If there is a backslash character in the string, the character after it (even another backslash) is put into the string verbatim, but the (first) backslash is not. .RE .TP \f[B]a\f[R] The value on top of the stack is popped. .RS .PP If it is a number, it is truncated and its absolute value is taken. The result mod \f[B]256\f[R] is calculated. If that result is \f[B]0\f[R], push an empty string; otherwise, push a one-character string where the character is the result of the mod interpreted as an ASCII character. .PP If it is a string, then a new string is made. If the original string is empty, the new string is empty. If it is not, then the first character of the original string is used to create the new string as a one-character string. The new string is then pushed onto the stack. .PP This is a \f[B]non-portable extension\f[R]. .RE .TP \f[B]x\f[R] Pops a value off of the top of the stack. .RS .PP If it is a number, it is pushed back onto the stack. .PP If it is a string, it is executed as a macro. .PP This behavior is the norm whenever a macro is executed, whether by this command or by the conditional execution commands below. .RE .TP \f[B]>\f[R]\f[I]r\f[R] Pops two values off of the stack that must be numbers and compares them. If the first value is greater than the second, then the contents of register \f[I]r\f[R] are executed. .RS .PP For example, \f[B]0 1>a\f[R] will execute the contents of register \f[B]a\f[R], and \f[B]1 0>a\f[R] will not. .PP If either or both of the values are not numbers, dc(1) will raise an error and reset (see the \f[B]RESET\f[R] section). .RE .TP \f[B]>\f[R]\f[I]r\f[R]\f[B]e\f[R]\f[I]s\f[R] Like the above, but will execute register \f[I]s\f[R] if the comparison fails. .RS .PP If either or both of the values are not numbers, dc(1) will raise an error and reset (see the \f[B]RESET\f[R] section). .PP This is a \f[B]non-portable extension\f[R]. .RE .TP \f[B]!>\f[R]\f[I]r\f[R] Pops two values off of the stack that must be numbers and compares them. If the first value is not greater than the second (less than or equal to), then the contents of register \f[I]r\f[R] are executed. .RS .PP If either or both of the values are not numbers, dc(1) will raise an error and reset (see the \f[B]RESET\f[R] section). .RE .TP \f[B]!>\f[R]\f[I]r\f[R]\f[B]e\f[R]\f[I]s\f[R] Like the above, but will execute register \f[I]s\f[R] if the comparison fails. .RS .PP If either or both of the values are not numbers, dc(1) will raise an error and reset (see the \f[B]RESET\f[R] section). .PP This is a \f[B]non-portable extension\f[R]. .RE .TP \f[B]<\f[R]\f[I]r\f[R] Pops two values off of the stack that must be numbers and compares them. If the first value is less than the second, then the contents of register \f[I]r\f[R] are executed. .RS .PP If either or both of the values are not numbers, dc(1) will raise an error and reset (see the \f[B]RESET\f[R] section). .RE .TP \f[B]<\f[R]\f[I]r\f[R]\f[B]e\f[R]\f[I]s\f[R] Like the above, but will execute register \f[I]s\f[R] if the comparison fails. .RS .PP If either or both of the values are not numbers, dc(1) will raise an error and reset (see the \f[B]RESET\f[R] section). .PP This is a \f[B]non-portable extension\f[R]. .RE .TP \f[B]!<\f[R]\f[I]r\f[R] Pops two values off of the stack that must be numbers and compares them. If the first value is not less than the second (greater than or equal to), then the contents of register \f[I]r\f[R] are executed. .RS .PP If either or both of the values are not numbers, dc(1) will raise an error and reset (see the \f[B]RESET\f[R] section). .RE .TP \f[B]!<\f[R]\f[I]r\f[R]\f[B]e\f[R]\f[I]s\f[R] Like the above, but will execute register \f[I]s\f[R] if the comparison fails. .RS .PP If either or both of the values are not numbers, dc(1) will raise an error and reset (see the \f[B]RESET\f[R] section). .PP This is a \f[B]non-portable extension\f[R]. .RE .TP \f[B]=\f[R]\f[I]r\f[R] Pops two values off of the stack that must be numbers and compares them. If the first value is equal to the second, then the contents of register \f[I]r\f[R] are executed. .RS .PP If either or both of the values are not numbers, dc(1) will raise an error and reset (see the \f[B]RESET\f[R] section). .RE .TP \f[B]=\f[R]\f[I]r\f[R]\f[B]e\f[R]\f[I]s\f[R] Like the above, but will execute register \f[I]s\f[R] if the comparison fails. .RS .PP If either or both of the values are not numbers, dc(1) will raise an error and reset (see the \f[B]RESET\f[R] section). .PP This is a \f[B]non-portable extension\f[R]. .RE .TP \f[B]!=\f[R]\f[I]r\f[R] Pops two values off of the stack that must be numbers and compares them. If the first value is not equal to the second, then the contents of register \f[I]r\f[R] are executed. .RS .PP If either or both of the values are not numbers, dc(1) will raise an error and reset (see the \f[B]RESET\f[R] section). .RE .TP \f[B]!=\f[R]\f[I]r\f[R]\f[B]e\f[R]\f[I]s\f[R] Like the above, but will execute register \f[I]s\f[R] if the comparison fails. .RS .PP If either or both of the values are not numbers, dc(1) will raise an error and reset (see the \f[B]RESET\f[R] section). .PP This is a \f[B]non-portable extension\f[R]. .RE .TP \f[B]?\f[R] Reads a line from the \f[B]stdin\f[R] and executes it. This is to allow macros to request input from users. .TP \f[B]q\f[R] During execution of a macro, this exits the execution of that macro and the execution of the macro that executed it. If there are no macros, or only one macro executing, dc(1) exits. .TP \f[B]Q\f[R] Pops a value from the stack which must be non-negative and is used the number of macro executions to pop off of the execution stack. If the number of levels to pop is greater than the number of executing macros, dc(1) exits. .TP \f[B],\f[R] Pushes the depth of the execution stack onto the stack. The execution stack is the stack of string executions. The number that is pushed onto the stack is exactly as many as is needed to make dc(1) exit with the \f[B]Q\f[R] command, so the sequence \f[B],Q\f[R] will make dc(1) exit. .SS Status .PP These commands query status of the stack or its top value. .TP \f[B]Z\f[R] Pops a value off of the stack. .RS .PP If it is a number, calculates the number of significant decimal digits it has and pushes the result. It will push \f[B]1\f[R] if the argument is \f[B]0\f[R] with no decimal places. .PP If it is a string, pushes the number of characters the string has. .RE .TP \f[B]X\f[R] Pops a value off of the stack. .RS .PP If it is a number, pushes the \f[I]scale\f[R] of the value onto the stack. .PP If it is a string, pushes \f[B]0\f[R]. .RE .TP \f[B]z\f[R] Pushes the current depth of the stack (before execution of this command) onto the stack. .TP \f[B]y\f[R]\f[I]r\f[R] Pushes the current stack depth of the register \f[I]r\f[R] onto the main stack. .RS .PP Because each register has a depth of \f[B]1\f[R] (with the value \f[B]0\f[R] in the top item) when dc(1) starts, dc(1) requires that each register\[cq]s stack must always have at least one item; dc(1) will give an error and reset otherwise (see the \f[B]RESET\f[R] section). This means that this command will never push \f[B]0\f[R]. .PP This is a \f[B]non-portable extension\f[R]. .RE .SS Arrays .PP These commands manipulate arrays. .TP \f[B]:\f[R]\f[I]r\f[R] Pops the top two values off of the stack. The second value will be stored in the array \f[I]r\f[R] (see the \f[B]REGISTERS\f[R] section), indexed by the first value. .TP \f[B];\f[R]\f[I]r\f[R] Pops the value on top of the stack and uses it as an index into the array \f[I]r\f[R]. The selected value is then pushed onto the stack. .TP \f[B]Y\f[R]\f[I]r\f[R] Pushes the length of the array \f[I]r\f[R] onto the stack. .RS .PP This is a \f[B]non-portable extension\f[R]. .RE .SS Global Settings .PP These commands retrieve global settings. These are the only commands that require multiple specific characters, and all of them begin with the letter \f[B]g\f[R]. Only the characters below are allowed after the character \f[B]g\f[R]; any other character produces a parse error (see the \f[B]ERRORS\f[R] section). .TP \f[B]gl\f[R] Pushes the line length set by \f[B]DC_LINE_LENGTH\f[R] (see the \f[B]ENVIRONMENT VARIABLES\f[R] section) onto the stack. .TP \f[B]gz\f[R] Pushes \f[B]0\f[R] onto the stack if the leading zero setting has not been enabled with the \f[B]-z\f[R] or \f[B]--leading-zeroes\f[R] options (see the \f[B]OPTIONS\f[R] section), non-zero otherwise. .SH REGISTERS .PP Registers are names that can store strings, numbers, and arrays. (Number/string registers do not interfere with array registers.) .PP Each register is also its own stack, so the current register value is the top of the stack for the register. All registers, when first referenced, have one value (\f[B]0\f[R]) in their stack, and it is a runtime error to attempt to pop that item off of the register stack. .PP In non-extended register mode, a register name is just the single character that follows any command that needs a register name. The only exceptions are: a newline (\f[B]`\[rs]n'\f[R]) and a left bracket (\f[B]`['\f[R]); it is a parse error for a newline or a left bracket to be used as a register name. .SS Extended Register Mode .PP Unlike most other dc(1) implentations, this dc(1) provides nearly unlimited amounts of registers, if extended register mode is enabled. .PP If extended register mode is enabled (\f[B]-x\f[R] or \f[B]--extended-register\f[R] command-line arguments are given), then normal single character registers are used \f[I]unless\f[R] the character immediately following a command that needs a register name is a space (according to \f[B]isspace()\f[R]) and not a newline (\f[B]`\[rs]n'\f[R]). .PP In that case, the register name is found according to the regex \f[B][a-z][a-z0-9_]*\f[R] (like bc(1) identifiers), and it is a parse error if the next non-space characters do not match that regex. .SH RESET .PP When dc(1) encounters an error or a signal that it has a non-default handler for, it resets. This means that several things happen. .PP First, any macros that are executing are stopped and popped off the stack. The behavior is not unlike that of exceptions in programming languages. Then the execution point is set so that any code waiting to execute (after all macros returned) is skipped. .PP Thus, when dc(1) resets, it skips any remaining code waiting to be executed. Then, if it is interactive mode, and the error was not a fatal error (see the \f[B]EXIT STATUS\f[R] section), it asks for more input; otherwise, it exits with the appropriate return code. .SH PERFORMANCE .PP Most dc(1) implementations use \f[B]char\f[R] types to calculate the value of \f[B]1\f[R] decimal digit at a time, but that can be slow. This dc(1) does something different. .PP It uses large integers to calculate more than \f[B]1\f[R] decimal digit at a time. If built in a environment where \f[B]DC_LONG_BIT\f[R] (see the \f[B]LIMITS\f[R] section) is \f[B]64\f[R], then each integer has \f[B]9\f[R] decimal digits. If built in an environment where \f[B]DC_LONG_BIT\f[R] is \f[B]32\f[R] then each integer has \f[B]4\f[R] decimal digits. This value (the number of decimal digits per large integer) is called \f[B]DC_BASE_DIGS\f[R]. .PP In addition, this dc(1) uses an even larger integer for overflow checking. This integer type depends on the value of \f[B]DC_LONG_BIT\f[R], but is always at least twice as large as the integer type used to store digits. .SH LIMITS .PP The following are the limits on dc(1): .TP \f[B]DC_LONG_BIT\f[R] The number of bits in the \f[B]long\f[R] type in the environment where dc(1) was built. This determines how many decimal digits can be stored in a single large integer (see the \f[B]PERFORMANCE\f[R] section). .TP \f[B]DC_BASE_DIGS\f[R] The number of decimal digits per large integer (see the \f[B]PERFORMANCE\f[R] section). Depends on \f[B]DC_LONG_BIT\f[R]. .TP \f[B]DC_BASE_POW\f[R] The max decimal number that each large integer can store (see \f[B]DC_BASE_DIGS\f[R]) plus \f[B]1\f[R]. Depends on \f[B]DC_BASE_DIGS\f[R]. .TP \f[B]DC_OVERFLOW_MAX\f[R] The max number that the overflow type (see the \f[B]PERFORMANCE\f[R] section) can hold. Depends on \f[B]DC_LONG_BIT\f[R]. .TP \f[B]DC_BASE_MAX\f[R] The maximum output base. Set at \f[B]DC_BASE_POW\f[R]. .TP \f[B]DC_DIM_MAX\f[R] The maximum size of arrays. Set at \f[B]SIZE_MAX-1\f[R]. .TP \f[B]DC_SCALE_MAX\f[R] The maximum \f[B]scale\f[R]. Set at \f[B]DC_OVERFLOW_MAX-1\f[R]. .TP \f[B]DC_STRING_MAX\f[R] The maximum length of strings. Set at \f[B]DC_OVERFLOW_MAX-1\f[R]. .TP \f[B]DC_NAME_MAX\f[R] The maximum length of identifiers. Set at \f[B]DC_OVERFLOW_MAX-1\f[R]. .TP \f[B]DC_NUM_MAX\f[R] The maximum length of a number (in decimal digits), which includes digits after the decimal point. Set at \f[B]DC_OVERFLOW_MAX-1\f[R]. .TP \f[B]DC_RAND_MAX\f[R] The maximum integer (inclusive) returned by the \f[B]\[cq]\f[R] command, if dc(1). Set at \f[B]2\[ha]DC_LONG_BIT-1\f[R]. .TP Exponent The maximum allowable exponent (positive or negative). Set at \f[B]DC_OVERFLOW_MAX\f[R]. .TP Number of vars The maximum number of vars/arrays. Set at \f[B]SIZE_MAX-1\f[R]. .PP These limits are meant to be effectively non-existent; the limits are so large (at least on 64-bit machines) that there should not be any point at which they become a problem. In fact, memory should be exhausted before these limits should be hit. .SH ENVIRONMENT VARIABLES .PP dc(1) recognizes the following environment variables: .TP \f[B]DC_ENV_ARGS\f[R] This is another way to give command-line arguments to dc(1). They should be in the same format as all other command-line arguments. These are always processed first, so any files given in \f[B]DC_ENV_ARGS\f[R] will be processed before arguments and files given on the command-line. This gives the user the ability to set up \[lq]standard\[rq] options and files to be used at every invocation. The most useful thing for such files to contain would be useful functions that the user might want every time dc(1) runs. Another use would be to use the \f[B]-e\f[R] option to set \f[B]scale\f[R] to a value other than \f[B]0\f[R]. .RS .PP The code that parses \f[B]DC_ENV_ARGS\f[R] will correctly handle quoted arguments, but it does not understand escape sequences. For example, the string \f[B]\[lq]/home/gavin/some dc file.dc\[rq]\f[R] will be correctly parsed, but the string \f[B]\[lq]/home/gavin/some \[dq]dc\[dq] file.dc\[rq]\f[R] will include the backslashes. .PP The quote parsing will handle either kind of quotes, \f[B]\[cq]\f[R] or \f[B]\[lq]\f[R]. Thus, if you have a file with any number of single quotes in the name, you can use double quotes as the outside quotes, as in \f[B]\[lq]some `dc' file.dc\[rq]\f[R], and vice versa if you have a file with double quotes. However, handling a file with both kinds of quotes in \f[B]DC_ENV_ARGS\f[R] is not supported due to the complexity of the parsing, though such files are still supported on the command-line where the parsing is done by the shell. .RE .TP \f[B]DC_LINE_LENGTH\f[R] If this environment variable exists and contains an integer that is greater than \f[B]1\f[R] and is less than \f[B]UINT16_MAX\f[R] (\f[B]2\[ha]16-1\f[R]), dc(1) will output lines to that length, including the backslash newline combo. The default line length is \f[B]70\f[R]. .RS .PP The special value of \f[B]0\f[R] will disable line length checking and print numbers without regard to line length and without backslashes and newlines. .RE .TP \f[B]DC_SIGINT_RESET\f[R] If dc(1) is not in interactive mode (see the \f[B]INTERACTIVE MODE\f[R] section), then this environment variable has no effect because dc(1) exits on \f[B]SIGINT\f[R] when not in interactive mode. .RS .PP However, when dc(1) is in interactive mode, then if this environment variable exists and contains an integer, a non-zero value makes dc(1) reset on \f[B]SIGINT\f[R], rather than exit, and zero makes dc(1) exit. If this environment variable exists and is \f[I]not\f[R] an integer, then dc(1) will exit on \f[B]SIGINT\f[R]. .PP This environment variable overrides the default, which can be queried with the \f[B]-h\f[R] or \f[B]--help\f[R] options. .RE .TP \f[B]DC_TTY_MODE\f[R] If TTY mode is \f[I]not\f[R] available (see the \f[B]TTY MODE\f[R] section), then this environment variable has no effect. .RS .PP However, when TTY mode is available, then if this environment variable exists and contains an integer, then a non-zero value makes dc(1) use TTY mode, and zero makes dc(1) not use TTY mode. .PP This environment variable overrides the default, which can be queried with the \f[B]-h\f[R] or \f[B]--help\f[R] options. .RE .TP \f[B]DC_PROMPT\f[R] If TTY mode is \f[I]not\f[R] available (see the \f[B]TTY MODE\f[R] section), then this environment variable has no effect. .RS .PP However, when TTY mode is available, then if this environment variable exists and contains an integer, a non-zero value makes dc(1) use a prompt, and zero or a non-integer makes dc(1) not use a prompt. If this environment variable does not exist and \f[B]DC_TTY_MODE\f[R] does, then the value of the \f[B]DC_TTY_MODE\f[R] environment variable is used. .PP This environment variable and the \f[B]DC_TTY_MODE\f[R] environment variable override the default, which can be queried with the \f[B]-h\f[R] or \f[B]--help\f[R] options. .RE +.TP +\f[B]DC_EXPR_EXIT\f[R] +If any expressions or expression files are given on the command-line +with \f[B]-e\f[R], \f[B]--expression\f[R], \f[B]-f\f[R], or +\f[B]--file\f[R], then if this environment variable exists and contains +an integer, a non-zero value makes dc(1) exit after executing the +expressions and expression files, and a non-zero value makes dc(1) not +exit. +.RS +.PP +This environment variable overrides the default, which can be queried +with the \f[B]-h\f[R] or \f[B]--help\f[R] options. +.RE .SH EXIT STATUS .PP dc(1) returns the following exit statuses: .TP \f[B]0\f[R] No error. .TP \f[B]1\f[R] A math error occurred. This follows standard practice of using \f[B]1\f[R] for expected errors, since math errors will happen in the process of normal execution. .RS .PP Math errors include divide by \f[B]0\f[R], taking the square root of a negative number, using a negative number as a bound for the pseudo-random number generator, attempting to convert a negative number to a hardware integer, overflow when converting a number to a hardware integer, overflow when calculating the size of a number, and attempting to use a non-integer where an integer is required. .PP Converting to a hardware integer happens for the second operand of the power (\f[B]\[ha]\f[R]), places (\f[B]\[at]\f[R]), left shift (\f[B]H\f[R]), and right shift (\f[B]h\f[R]) operators. .RE .TP \f[B]2\f[R] A parse error occurred. .RS .PP Parse errors include unexpected \f[B]EOF\f[R], using an invalid character, failing to find the end of a string or comment, and using a token where it is invalid. .RE .TP \f[B]3\f[R] A runtime error occurred. .RS .PP Runtime errors include assigning an invalid number to any global (\f[B]ibase\f[R], \f[B]obase\f[R], or \f[B]scale\f[R]), giving a bad expression to a \f[B]read()\f[R] call, calling \f[B]read()\f[R] inside of a \f[B]read()\f[R] call, type errors (including attempting to execute a number), and attempting an operation when the stack has too few elements. .RE .TP \f[B]4\f[R] A fatal error occurred. .RS .PP Fatal errors include memory allocation errors, I/O errors, failing to open files, attempting to use files that do not have only ASCII characters (dc(1) only accepts ASCII characters), attempting to open a directory as a file, and giving invalid command-line options. .RE .PP The exit status \f[B]4\f[R] is special; when a fatal error occurs, dc(1) always exits and returns \f[B]4\f[R], no matter what mode dc(1) is in. .PP The other statuses will only be returned when dc(1) is not in interactive mode (see the \f[B]INTERACTIVE MODE\f[R] section), since dc(1) resets its state (see the \f[B]RESET\f[R] section) and accepts more input when one of those errors occurs in interactive mode. This is also the case when interactive mode is forced by the \f[B]-i\f[R] flag or \f[B]--interactive\f[R] option. .PP These exit statuses allow dc(1) to be used in shell scripting with error checking, and its normal behavior can be forced by using the \f[B]-i\f[R] flag or \f[B]--interactive\f[R] option. .SH INTERACTIVE MODE .PP Like bc(1), dc(1) has an interactive mode and a non-interactive mode. Interactive mode is turned on automatically when both \f[B]stdin\f[R] and \f[B]stdout\f[R] are hooked to a terminal, but the \f[B]-i\f[R] flag and \f[B]--interactive\f[R] option can turn it on in other situations. .PP In interactive mode, dc(1) attempts to recover from errors (see the \f[B]RESET\f[R] section), and in normal execution, flushes \f[B]stdout\f[R] as soon as execution is done for the current input. dc(1) may also reset on \f[B]SIGINT\f[R] instead of exit, depending on the contents of, or default for, the \f[B]DC_SIGINT_RESET\f[R] environment variable (see the \f[B]ENVIRONMENT VARIABLES\f[R] section). .SH TTY MODE .PP If \f[B]stdin\f[R], \f[B]stdout\f[R], and \f[B]stderr\f[R] are all connected to a TTY, then \[lq]TTY mode\[rq] is considered to be available, and thus, dc(1) can turn on TTY mode, subject to some settings. .PP If there is the environment variable \f[B]DC_TTY_MODE\f[R] in the environment (see the \f[B]ENVIRONMENT VARIABLES\f[R] section), then if that environment variable contains a non-zero integer, dc(1) will turn on TTY mode when \f[B]stdin\f[R], \f[B]stdout\f[R], and \f[B]stderr\f[R] are all connected to a TTY. If the \f[B]DC_TTY_MODE\f[R] environment variable exists but is \f[I]not\f[R] a non-zero integer, then dc(1) will not turn TTY mode on. .PP If the environment variable \f[B]DC_TTY_MODE\f[R] does \f[I]not\f[R] exist, the default setting is used. The default setting can be queried with the \f[B]-h\f[R] or \f[B]--help\f[R] options. .PP TTY mode is different from interactive mode because interactive mode is required in the bc(1) specification (https://pubs.opengroup.org/onlinepubs/9699919799/utilities/bc.html), and interactive mode requires only \f[B]stdin\f[R] and \f[B]stdout\f[R] to be connected to a terminal. .SS Command-Line History .PP Command-line history is only enabled if TTY mode is, i.e., that \f[B]stdin\f[R], \f[B]stdout\f[R], and \f[B]stderr\f[R] are connected to a TTY and the \f[B]DC_TTY_MODE\f[R] environment variable (see the \f[B]ENVIRONMENT VARIABLES\f[R] section) and its default do not disable TTY mode. See the \f[B]COMMAND LINE HISTORY\f[R] section for more information. .SS Prompt .PP If TTY mode is available, then a prompt can be enabled. Like TTY mode itself, it can be turned on or off with an environment variable: \f[B]DC_PROMPT\f[R] (see the \f[B]ENVIRONMENT VARIABLES\f[R] section). .PP If the environment variable \f[B]DC_PROMPT\f[R] exists and is a non-zero integer, then the prompt is turned on when \f[B]stdin\f[R], \f[B]stdout\f[R], and \f[B]stderr\f[R] are connected to a TTY and the \f[B]-P\f[R] and \f[B]--no-prompt\f[R] options were not used. The read prompt will be turned on under the same conditions, except that the \f[B]-R\f[R] and \f[B]--no-read-prompt\f[R] options must also not be used. .PP However, if \f[B]DC_PROMPT\f[R] does not exist, the prompt can be enabled or disabled with the \f[B]DC_TTY_MODE\f[R] environment variable, the \f[B]-P\f[R] and \f[B]--no-prompt\f[R] options, and the \f[B]-R\f[R] and \f[B]--no-read-prompt\f[R] options. See the \f[B]ENVIRONMENT VARIABLES\f[R] and \f[B]OPTIONS\f[R] sections for more details. .SH SIGNAL HANDLING .PP Sending a \f[B]SIGINT\f[R] will cause dc(1) to do one of two things. .PP If dc(1) is not in interactive mode (see the \f[B]INTERACTIVE MODE\f[R] section), or the \f[B]DC_SIGINT_RESET\f[R] environment variable (see the \f[B]ENVIRONMENT VARIABLES\f[R] section), or its default, is either not an integer or it is zero, dc(1) will exit. .PP However, if dc(1) is in interactive mode, and the \f[B]DC_SIGINT_RESET\f[R] or its default is an integer and non-zero, then dc(1) will stop executing the current input and reset (see the \f[B]RESET\f[R] section) upon receiving a \f[B]SIGINT\f[R]. .PP Note that \[lq]current input\[rq] can mean one of two things. If dc(1) is processing input from \f[B]stdin\f[R] in interactive mode, it will ask for more input. If dc(1) is processing input from a file in interactive mode, it will stop processing the file and start processing the next file, if one exists, or ask for input from \f[B]stdin\f[R] if no other file exists. .PP This means that if a \f[B]SIGINT\f[R] is sent to dc(1) as it is executing a file, it can seem as though dc(1) did not respond to the signal since it will immediately start executing the next file. This is by design; most files that users execute when interacting with dc(1) have function definitions, which are quick to parse. If a file takes a long time to execute, there may be a bug in that file. The rest of the files could still be executed without problem, allowing the user to continue. .PP \f[B]SIGTERM\f[R] and \f[B]SIGQUIT\f[R] cause dc(1) to clean up and exit, and it uses the default handler for all other signals. The one exception is \f[B]SIGHUP\f[R]; in that case, and only when dc(1) is in TTY mode (see the \f[B]TTY MODE\f[R] section), a \f[B]SIGHUP\f[R] will cause dc(1) to clean up and exit. .SH COMMAND LINE HISTORY .PP dc(1) supports interactive command-line editing. .PP If dc(1) can be in TTY mode (see the \f[B]TTY MODE\f[R] section), history can be enabled. This means that command-line history can only be enabled when \f[B]stdin\f[R], \f[B]stdout\f[R], and \f[B]stderr\f[R] are all connected to a TTY. .PP Like TTY mode itself, it can be turned on or off with the environment variable \f[B]DC_TTY_MODE\f[R] (see the \f[B]ENVIRONMENT VARIABLES\f[R] section). .PP \f[B]Note\f[R]: tabs are converted to 8 spaces. .SH LOCALES .PP This dc(1) ships with support for adding error messages for different locales and thus, supports \f[B]LC_MESSAGES\f[R]. .SH SEE ALSO .PP bc(1) .SH STANDARDS .PP The dc(1) utility operators are compliant with the operators in the bc(1) IEEE Std 1003.1-2017 (\[lq]POSIX.1-2017\[rq]) (https://pubs.opengroup.org/onlinepubs/9699919799/utilities/bc.html) specification. .SH BUGS .PP None are known. Report bugs at https://git.yzena.com/gavin/bc. .SH AUTHOR .PP Gavin D. Howard and contributors. diff --git a/contrib/bc/manuals/dc/A.1.md b/contrib/bc/manuals/dc/A.1.md index 0007cc76760a..618543d7f397 100644 --- a/contrib/bc/manuals/dc/A.1.md +++ b/contrib/bc/manuals/dc/A.1.md @@ -1,1384 +1,1395 @@ # Name dc - arbitrary-precision decimal reverse-Polish notation calculator # SYNOPSIS **dc** [**-hiPRvVx**] [**-\-version**] [**-\-help**] [**-\-interactive**] [**-\-no-prompt**] [**-\-no-read-prompt**] [**-\-extended-register**] [**-e** *expr*] [**-\-expression**=*expr*...] [**-f** *file*...] [**-\-file**=*file*...] [*file*...] # DESCRIPTION dc(1) is an arbitrary-precision calculator. It uses a stack (reverse Polish notation) to store numbers and results of computations. Arithmetic operations pop arguments off of the stack and push the results. If no files are given on the command-line, then dc(1) reads from **stdin** (see the **STDIN** section). Otherwise, those files are processed, and dc(1) will then exit. If a user wants to set up a standard environment, they can use **DC_ENV_ARGS** (see the **ENVIRONMENT VARIABLES** section). For example, if a user wants the **scale** always set to **10**, they can set **DC_ENV_ARGS** to **-e 10k**, and this dc(1) will always start with a **scale** of **10**. # OPTIONS The following are the options that dc(1) accepts. **-h**, **-\-help** : Prints a usage message and quits. **-v**, **-V**, **-\-version** : Print the version information (copyright header) and exit. **-i**, **-\-interactive** : Forces interactive mode. (See the **INTERACTIVE MODE** section.) This is a **non-portable extension**. **-L**, **-\-no-line-length** : Disables line length checking and prints numbers without backslashes and newlines. In other words, this option sets **BC_LINE_LENGTH** to **0** (see the **ENVIRONMENT VARIABLES** section). This is a **non-portable extension**. **-P**, **-\-no-prompt** : Disables the prompt in TTY mode. (The prompt is only enabled in TTY mode. See the **TTY MODE** section.) This is mostly for those users that do not want a prompt or are not used to having them in dc(1). Most of those users would want to put this option in **DC_ENV_ARGS**. These options override the **DC_PROMPT** and **DC_TTY_MODE** environment variables (see the **ENVIRONMENT VARIABLES** section). This is a **non-portable extension**. **-R**, **-\-no-read-prompt** : Disables the read prompt in TTY mode. (The read prompt is only enabled in TTY mode. See the **TTY MODE** section.) This is mostly for those users that do not want a read prompt or are not used to having them in dc(1). Most of those users would want to put this option in **BC_ENV_ARGS** (see the **ENVIRONMENT VARIABLES** section). This option is also useful in hash bang lines of dc(1) scripts that prompt for user input. This option does not disable the regular prompt because the read prompt is only used when the **?** command is used. These options *do* override the **DC_PROMPT** and **DC_TTY_MODE** environment variables (see the **ENVIRONMENT VARIABLES** section), but only for the read prompt. This is a **non-portable extension**. **-x** **-\-extended-register** : Enables extended register mode. See the *Extended Register Mode* subsection of the **REGISTERS** section for more information. This is a **non-portable extension**. **-z**, **-\-leading-zeroes** : Makes bc(1) print all numbers greater than **-1** and less than **1**, and not equal to **0**, with a leading zero. This can be set for individual numbers with the **plz(x)**, plznl(x)**, **pnlz(x)**, and **pnlznl(x)** functions in the extended math library (see the **LIBRARY** section). This is a **non-portable extension**. **-e** *expr*, **-\-expression**=*expr* : Evaluates *expr*. If multiple expressions are given, they are evaluated in order. If files are given as well (see below), the expressions and files are evaluated in the order given. This means that if a file is given before an expression, the file is read in and evaluated first. If this option is given on the command-line (i.e., not in **DC_ENV_ARGS**, see the **ENVIRONMENT VARIABLES** section), then after processing all expressions and files, dc(1) will exit, unless **-** (**stdin**) was given as an argument at least once to **-f** or **-\-file**, whether on the command-line or in **DC_ENV_ARGS**. However, if any other **-e**, **-\-expression**, **-f**, or **-\-file** arguments are given after **-f-** or equivalent is given, dc(1) will give a fatal error and exit. This is a **non-portable extension**. **-f** *file*, **-\-file**=*file* : Reads in *file* and evaluates it, line by line, as though it were read through **stdin**. If expressions are also given (see above), the expressions are evaluated in the order given. If this option is given on the command-line (i.e., not in **DC_ENV_ARGS**, see the **ENVIRONMENT VARIABLES** section), then after processing all expressions and files, dc(1) will exit, unless **-** (**stdin**) was given as an argument at least once to **-f** or **-\-file**. However, if any other **-e**, **-\-expression**, **-f**, or **-\-file** arguments are given after **-f-** or equivalent is given, dc(1) will give a fatal error and exit. This is a **non-portable extension**. All long options are **non-portable extensions**. # STDIN If no files are given on the command-line and no files or expressions are given by the **-f**, **-\-file**, **-e**, or **-\-expression** options, then dc(1) read from **stdin**. However, there is a caveat to this. First, **stdin** is evaluated a line at a time. The only exception to this is if a string has been finished, but not ended. This means that, except for escaped brackets, all brackets must be balanced before dc(1) parses and executes. # STDOUT Any non-error output is written to **stdout**. In addition, if history (see the **HISTORY** section) and the prompt (see the **TTY MODE** section) are enabled, both are output to **stdout**. **Note**: Unlike other dc(1) implementations, this dc(1) will issue a fatal error (see the **EXIT STATUS** section) if it cannot write to **stdout**, so if **stdout** is closed, as in **dc >&-**, it will quit with an error. This is done so that dc(1) can report problems when **stdout** is redirected to a file. If there are scripts that depend on the behavior of other dc(1) implementations, it is recommended that those scripts be changed to redirect **stdout** to **/dev/null**. # STDERR Any error output is written to **stderr**. **Note**: Unlike other dc(1) implementations, this dc(1) will issue a fatal error (see the **EXIT STATUS** section) if it cannot write to **stderr**, so if **stderr** is closed, as in **dc 2>&-**, it will quit with an error. This is done so that dc(1) can exit with an error code when **stderr** is redirected to a file. If there are scripts that depend on the behavior of other dc(1) implementations, it is recommended that those scripts be changed to redirect **stderr** to **/dev/null**. # SYNTAX Each item in the input source code, either a number (see the **NUMBERS** section) or a command (see the **COMMANDS** section), is processed and executed, in order. Input is processed immediately when entered. **ibase** is a register (see the **REGISTERS** section) that determines how to interpret constant numbers. It is the "input" base, or the number base used for interpreting input numbers. **ibase** is initially **10**. The max allowable value for **ibase** is **16**. The min allowable value for **ibase** is **2**. The max allowable value for **ibase** can be queried in dc(1) programs with the **T** command. **obase** is a register (see the **REGISTERS** section) that determines how to output results. It is the "output" base, or the number base used for outputting numbers. **obase** is initially **10**. The max allowable value for **obase** is **DC_BASE_MAX** and can be queried with the **U** command. The min allowable value for **obase** is **0**. If **obase** is **0**, values are output in scientific notation, and if **obase** is **1**, values are output in engineering notation. Otherwise, values are output in the specified base. Outputting in scientific and engineering notations are **non-portable extensions**. The *scale* of an expression is the number of digits in the result of the expression right of the decimal point, and **scale** is a register (see the **REGISTERS** section) that sets the precision of any operations (with exceptions). **scale** is initially **0**. **scale** cannot be negative. The max allowable value for **scale** can be queried in dc(1) programs with the **V** command. **seed** is a register containing the current seed for the pseudo-random number generator. If the current value of **seed** is queried and stored, then if it is assigned to **seed** later, the pseudo-random number generator is guaranteed to produce the same sequence of pseudo-random numbers that were generated after the value of **seed** was first queried. Multiple values assigned to **seed** can produce the same sequence of pseudo-random numbers. Likewise, when a value is assigned to **seed**, it is not guaranteed that querying **seed** immediately after will return the same value. In addition, the value of **seed** will change after any call to the **'** command or the **"** command that does not get receive a value of **0** or **1**. The maximum integer returned by the **'** command can be queried with the **W** command. **Note**: The values returned by the pseudo-random number generator with the **'** and **"** commands are guaranteed to **NOT** be cryptographically secure. This is a consequence of using a seeded pseudo-random number generator. However, they *are* guaranteed to be reproducible with identical **seed** values. This means that the pseudo-random values from dc(1) should only be used where a reproducible stream of pseudo-random numbers is *ESSENTIAL*. In any other case, use a non-seeded pseudo-random number generator. The pseudo-random number generator, **seed**, and all associated operations are **non-portable extensions**. ## Comments Comments go from **#** until, and not including, the next newline. This is a **non-portable extension**. # NUMBERS Numbers are strings made up of digits, uppercase letters up to **F**, and at most **1** period for a radix. Numbers can have up to **DC_NUM_MAX** digits. Uppercase letters are equal to **9** + their position in the alphabet (i.e., **A** equals **10**, or **9+1**). If a digit or letter makes no sense with the current value of **ibase**, they are set to the value of the highest valid digit in **ibase**. Single-character numbers (i.e., **A** alone) take the value that they would have if they were valid digits, regardless of the value of **ibase**. This means that **A** alone always equals decimal **10** and **F** alone always equals decimal **15**. In addition, dc(1) accepts numbers in scientific notation. These have the form **\e\**. The exponent (the portion after the **e**) must be an integer. An example is **1.89237e9**, which is equal to **1892370000**. Negative exponents are also allowed, so **4.2890e_3** is equal to **0.0042890**. **WARNING**: Both the number and the exponent in scientific notation are interpreted according to the current **ibase**, but the number is still multiplied by **10\^exponent** regardless of the current **ibase**. For example, if **ibase** is **16** and dc(1) is given the number string **FFeA**, the resulting decimal number will be **2550000000000**, and if dc(1) is given the number string **10e_4**, the resulting decimal number will be **0.0016**. Accepting input as scientific notation is a **non-portable extension**. # COMMANDS The valid commands are listed below. ## Printing These commands are used for printing. Note that both scientific notation and engineering notation are available for printing numbers. Scientific notation is activated by assigning **0** to **obase** using **0o**, and engineering notation is activated by assigning **1** to **obase** using **1o**. To deactivate them, just assign a different value to **obase**. Printing numbers in scientific notation and/or engineering notation is a **non-portable extension**. **p** : Prints the value on top of the stack, whether number or string, and prints a newline after. This does not alter the stack. **n** : Prints the value on top of the stack, whether number or string, and pops it off of the stack. **P** : Pops a value off the stack. If the value is a number, it is truncated and the absolute value of the result is printed as though **obase** is **256** and each digit is interpreted as an 8-bit ASCII character, making it a byte stream. If the value is a string, it is printed without a trailing newline. This is a **non-portable extension**. **f** : Prints the entire contents of the stack, in order from newest to oldest, without altering anything. Users should use this command when they get lost. ## Arithmetic These are the commands used for arithmetic. **+** : The top two values are popped off the stack, added, and the result is pushed onto the stack. The *scale* of the result is equal to the max *scale* of both operands. **-** : The top two values are popped off the stack, subtracted, and the result is pushed onto the stack. The *scale* of the result is equal to the max *scale* of both operands. **\*** : The top two values are popped off the stack, multiplied, and the result is pushed onto the stack. If **a** is the *scale* of the first expression and **b** is the *scale* of the second expression, the *scale* of the result is equal to **min(a+b,max(scale,a,b))** where **min()** and **max()** return the obvious values. **/** : The top two values are popped off the stack, divided, and the result is pushed onto the stack. The *scale* of the result is equal to **scale**. The first value popped off of the stack must be non-zero. **%** : The top two values are popped off the stack, remaindered, and the result is pushed onto the stack. Remaindering is equivalent to 1) Computing **a/b** to current **scale**, and 2) Using the result of step 1 to calculate **a-(a/b)\*b** to *scale* **max(scale+scale(b),scale(a))**. The first value popped off of the stack must be non-zero. **~** : The top two values are popped off the stack, divided and remaindered, and the results (divided first, remainder second) are pushed onto the stack. This is equivalent to **x y / x y %** except that **x** and **y** are only evaluated once. The first value popped off of the stack must be non-zero. This is a **non-portable extension**. **\^** : The top two values are popped off the stack, the second is raised to the power of the first, and the result is pushed onto the stack. The *scale* of the result is equal to **scale**. The first value popped off of the stack must be an integer, and if that value is negative, the second value popped off of the stack must be non-zero. **v** : The top value is popped off the stack, its square root is computed, and the result is pushed onto the stack. The *scale* of the result is equal to **scale**. The value popped off of the stack must be non-negative. **\_** : If this command *immediately* precedes a number (i.e., no spaces or other commands), then that number is input as a negative number. Otherwise, the top value on the stack is popped and copied, and the copy is negated and pushed onto the stack. This behavior without a number is a **non-portable extension**. **b** : The top value is popped off the stack, and if it is zero, it is pushed back onto the stack. Otherwise, its absolute value is pushed onto the stack. This is a **non-portable extension**. **|** : The top three values are popped off the stack, a modular exponentiation is computed, and the result is pushed onto the stack. The first value popped is used as the reduction modulus and must be an integer and non-zero. The second value popped is used as the exponent and must be an integer and non-negative. The third value popped is the base and must be an integer. This is a **non-portable extension**. **\$** : The top value is popped off the stack and copied, and the copy is truncated and pushed onto the stack. This is a **non-portable extension**. **\@** : The top two values are popped off the stack, and the precision of the second is set to the value of the first, whether by truncation or extension. The first value popped off of the stack must be an integer and non-negative. This is a **non-portable extension**. **H** : The top two values are popped off the stack, and the second is shifted left (radix shifted right) to the value of the first. The first value popped off of the stack must be an integer and non-negative. This is a **non-portable extension**. **h** : The top two values are popped off the stack, and the second is shifted right (radix shifted left) to the value of the first. The first value popped off of the stack must be an integer and non-negative. This is a **non-portable extension**. **G** : The top two values are popped off of the stack, they are compared, and a **1** is pushed if they are equal, or **0** otherwise. This is a **non-portable extension**. **N** : The top value is popped off of the stack, and if it a **0**, a **1** is pushed; otherwise, a **0** is pushed. This is a **non-portable extension**. **(** : The top two values are popped off of the stack, they are compared, and a **1** is pushed if the first is less than the second, or **0** otherwise. This is a **non-portable extension**. **{** : The top two values are popped off of the stack, they are compared, and a **1** is pushed if the first is less than or equal to the second, or **0** otherwise. This is a **non-portable extension**. **)** : The top two values are popped off of the stack, they are compared, and a **1** is pushed if the first is greater than the second, or **0** otherwise. This is a **non-portable extension**. **}** : The top two values are popped off of the stack, they are compared, and a **1** is pushed if the first is greater than or equal to the second, or **0** otherwise. This is a **non-portable extension**. **M** : The top two values are popped off of the stack. If they are both non-zero, a **1** is pushed onto the stack. If either of them is zero, or both of them are, then a **0** is pushed onto the stack. This is like the **&&** operator in bc(1), and it is *not* a short-circuit operator. This is a **non-portable extension**. **m** : The top two values are popped off of the stack. If at least one of them is non-zero, a **1** is pushed onto the stack. If both of them are zero, then a **0** is pushed onto the stack. This is like the **||** operator in bc(1), and it is *not* a short-circuit operator. This is a **non-portable extension**. ## Pseudo-Random Number Generator dc(1) has a built-in pseudo-random number generator. These commands query the pseudo-random number generator. (See Parameters for more information about the **seed** value that controls the pseudo-random number generator.) The pseudo-random number generator is guaranteed to **NOT** be cryptographically secure. **'** : Generates an integer between 0 and **DC_RAND_MAX**, inclusive (see the **LIMITS** section). The generated integer is made as unbiased as possible, subject to the limitations of the pseudo-random number generator. This is a **non-portable extension**. **"** : Pops a value off of the stack, which is used as an **exclusive** upper bound on the integer that will be generated. If the bound is negative or is a non-integer, an error is raised, and dc(1) resets (see the **RESET** section) while **seed** remains unchanged. If the bound is larger than **DC_RAND_MAX**, the higher bound is honored by generating several pseudo-random integers, multiplying them by appropriate powers of **DC_RAND_MAX+1**, and adding them together. Thus, the size of integer that can be generated with this command is unbounded. Using this command will change the value of **seed**, unless the operand is **0** or **1**. In that case, **0** is pushed onto the stack, and **seed** is *not* changed. The generated integer is made as unbiased as possible, subject to the limitations of the pseudo-random number generator. This is a **non-portable extension**. ## Stack Control These commands control the stack. **c** : Removes all items from ("clears") the stack. **d** : Copies the item on top of the stack ("duplicates") and pushes the copy onto the stack. **r** : Swaps ("reverses") the two top items on the stack. **R** : Pops ("removes") the top value from the stack. ## Register Control These commands control registers (see the **REGISTERS** section). **s**_r_ : Pops the value off the top of the stack and stores it into register *r*. **l**_r_ : Copies the value in register *r* and pushes it onto the stack. This does not alter the contents of *r*. **S**_r_ : Pops the value off the top of the (main) stack and pushes it onto the stack of register *r*. The previous value of the register becomes inaccessible. **L**_r_ : Pops the value off the top of the stack for register *r* and push it onto the main stack. The previous value in the stack for register *r*, if any, is now accessible via the **l**_r_ command. ## Parameters These commands control the values of **ibase**, **obase**, **scale**, and **seed**. Also see the **SYNTAX** section. **i** : Pops the value off of the top of the stack and uses it to set **ibase**, which must be between **2** and **16**, inclusive. If the value on top of the stack has any *scale*, the *scale* is ignored. **o** : Pops the value off of the top of the stack and uses it to set **obase**, which must be between **0** and **DC_BASE_MAX**, inclusive (see the **LIMITS** section and the **NUMBERS** section). If the value on top of the stack has any *scale*, the *scale* is ignored. **k** : Pops the value off of the top of the stack and uses it to set **scale**, which must be non-negative. If the value on top of the stack has any *scale*, the *scale* is ignored. **j** : Pops the value off of the top of the stack and uses it to set **seed**. The meaning of **seed** is dependent on the current pseudo-random number generator but is guaranteed to not change except for new major versions. The *scale* and sign of the value may be significant. If a previously used **seed** value is used again, the pseudo-random number generator is guaranteed to produce the same sequence of pseudo-random numbers as it did when the **seed** value was previously used. The exact value assigned to **seed** is not guaranteed to be returned if the **J** command is used. However, if **seed** *does* return a different value, both values, when assigned to **seed**, are guaranteed to produce the same sequence of pseudo-random numbers. This means that certain values assigned to **seed** will not produce unique sequences of pseudo-random numbers. There is no limit to the length (number of significant decimal digits) or *scale* of the value that can be assigned to **seed**. This is a **non-portable extension**. **I** : Pushes the current value of **ibase** onto the main stack. **O** : Pushes the current value of **obase** onto the main stack. **K** : Pushes the current value of **scale** onto the main stack. **J** : Pushes the current value of **seed** onto the main stack. This is a **non-portable extension**. **T** : Pushes the maximum allowable value of **ibase** onto the main stack. This is a **non-portable extension**. **U** : Pushes the maximum allowable value of **obase** onto the main stack. This is a **non-portable extension**. **V** : Pushes the maximum allowable value of **scale** onto the main stack. This is a **non-portable extension**. **W** : Pushes the maximum (inclusive) integer that can be generated with the **'** pseudo-random number generator command. This is a **non-portable extension**. ## Strings The following commands control strings. dc(1) can work with both numbers and strings, and registers (see the **REGISTERS** section) can hold both strings and numbers. dc(1) always knows whether the contents of a register are a string or a number. While arithmetic operations have to have numbers, and will print an error if given a string, other commands accept strings. Strings can also be executed as macros. For example, if the string **[1pR]** is executed as a macro, then the code **1pR** is executed, meaning that the **1** will be printed with a newline after and then popped from the stack. **\[**_characters_**\]** : Makes a string containing *characters* and pushes it onto the stack. If there are brackets (**\[** and **\]**) in the string, then they must be balanced. Unbalanced brackets can be escaped using a backslash (**\\**) character. If there is a backslash character in the string, the character after it (even another backslash) is put into the string verbatim, but the (first) backslash is not. **a** : The value on top of the stack is popped. If it is a number, it is truncated and its absolute value is taken. The result mod **256** is calculated. If that result is **0**, push an empty string; otherwise, push a one-character string where the character is the result of the mod interpreted as an ASCII character. If it is a string, then a new string is made. If the original string is empty, the new string is empty. If it is not, then the first character of the original string is used to create the new string as a one-character string. The new string is then pushed onto the stack. This is a **non-portable extension**. **x** : Pops a value off of the top of the stack. If it is a number, it is pushed back onto the stack. If it is a string, it is executed as a macro. This behavior is the norm whenever a macro is executed, whether by this command or by the conditional execution commands below. **\>**_r_ : Pops two values off of the stack that must be numbers and compares them. If the first value is greater than the second, then the contents of register *r* are executed. For example, **0 1>a** will execute the contents of register **a**, and **1 0>a** will not. If either or both of the values are not numbers, dc(1) will raise an error and reset (see the **RESET** section). **>**_r_**e**_s_ : Like the above, but will execute register *s* if the comparison fails. If either or both of the values are not numbers, dc(1) will raise an error and reset (see the **RESET** section). This is a **non-portable extension**. **!\>**_r_ : Pops two values off of the stack that must be numbers and compares them. If the first value is not greater than the second (less than or equal to), then the contents of register *r* are executed. If either or both of the values are not numbers, dc(1) will raise an error and reset (see the **RESET** section). **!\>**_r_**e**_s_ : Like the above, but will execute register *s* if the comparison fails. If either or both of the values are not numbers, dc(1) will raise an error and reset (see the **RESET** section). This is a **non-portable extension**. **\<**_r_ : Pops two values off of the stack that must be numbers and compares them. If the first value is less than the second, then the contents of register *r* are executed. If either or both of the values are not numbers, dc(1) will raise an error and reset (see the **RESET** section). **\<**_r_**e**_s_ : Like the above, but will execute register *s* if the comparison fails. If either or both of the values are not numbers, dc(1) will raise an error and reset (see the **RESET** section). This is a **non-portable extension**. **!\<**_r_ : Pops two values off of the stack that must be numbers and compares them. If the first value is not less than the second (greater than or equal to), then the contents of register *r* are executed. If either or both of the values are not numbers, dc(1) will raise an error and reset (see the **RESET** section). **!\<**_r_**e**_s_ : Like the above, but will execute register *s* if the comparison fails. If either or both of the values are not numbers, dc(1) will raise an error and reset (see the **RESET** section). This is a **non-portable extension**. **=**_r_ : Pops two values off of the stack that must be numbers and compares them. If the first value is equal to the second, then the contents of register *r* are executed. If either or both of the values are not numbers, dc(1) will raise an error and reset (see the **RESET** section). **=**_r_**e**_s_ : Like the above, but will execute register *s* if the comparison fails. If either or both of the values are not numbers, dc(1) will raise an error and reset (see the **RESET** section). This is a **non-portable extension**. **!=**_r_ : Pops two values off of the stack that must be numbers and compares them. If the first value is not equal to the second, then the contents of register *r* are executed. If either or both of the values are not numbers, dc(1) will raise an error and reset (see the **RESET** section). **!=**_r_**e**_s_ : Like the above, but will execute register *s* if the comparison fails. If either or both of the values are not numbers, dc(1) will raise an error and reset (see the **RESET** section). This is a **non-portable extension**. **?** : Reads a line from the **stdin** and executes it. This is to allow macros to request input from users. **q** : During execution of a macro, this exits the execution of that macro and the execution of the macro that executed it. If there are no macros, or only one macro executing, dc(1) exits. **Q** : Pops a value from the stack which must be non-negative and is used the number of macro executions to pop off of the execution stack. If the number of levels to pop is greater than the number of executing macros, dc(1) exits. **,** : Pushes the depth of the execution stack onto the stack. The execution stack is the stack of string executions. The number that is pushed onto the stack is exactly as many as is needed to make dc(1) exit with the **Q** command, so the sequence **,Q** will make dc(1) exit. ## Status These commands query status of the stack or its top value. **Z** : Pops a value off of the stack. If it is a number, calculates the number of significant decimal digits it has and pushes the result. It will push **1** if the argument is **0** with no decimal places. If it is a string, pushes the number of characters the string has. **X** : Pops a value off of the stack. If it is a number, pushes the *scale* of the value onto the stack. If it is a string, pushes **0**. **z** : Pushes the current depth of the stack (before execution of this command) onto the stack. **y**_r_ : Pushes the current stack depth of the register *r* onto the main stack. Because each register has a depth of **1** (with the value **0** in the top item) when dc(1) starts, dc(1) requires that each register's stack must always have at least one item; dc(1) will give an error and reset otherwise (see the **RESET** section). This means that this command will never push **0**. This is a **non-portable extension**. ## Arrays These commands manipulate arrays. **:**_r_ : Pops the top two values off of the stack. The second value will be stored in the array *r* (see the **REGISTERS** section), indexed by the first value. **;**_r_ : Pops the value on top of the stack and uses it as an index into the array *r*. The selected value is then pushed onto the stack. **Y**_r_ : Pushes the length of the array *r* onto the stack. This is a **non-portable extension**. ## Global Settings These commands retrieve global settings. These are the only commands that require multiple specific characters, and all of them begin with the letter **g**. Only the characters below are allowed after the character **g**; any other character produces a parse error (see the **ERRORS** section). **gl** : Pushes the line length set by **DC_LINE_LENGTH** (see the **ENVIRONMENT VARIABLES** section) onto the stack. **gz** : Pushes **0** onto the stack if the leading zero setting has not been enabled with the **-z** or **-\-leading-zeroes** options (see the **OPTIONS** section), non-zero otherwise. # REGISTERS Registers are names that can store strings, numbers, and arrays. (Number/string registers do not interfere with array registers.) Each register is also its own stack, so the current register value is the top of the stack for the register. All registers, when first referenced, have one value (**0**) in their stack, and it is a runtime error to attempt to pop that item off of the register stack. In non-extended register mode, a register name is just the single character that follows any command that needs a register name. The only exceptions are: a newline (**'\\n'**) and a left bracket (**'['**); it is a parse error for a newline or a left bracket to be used as a register name. ## Extended Register Mode Unlike most other dc(1) implentations, this dc(1) provides nearly unlimited amounts of registers, if extended register mode is enabled. If extended register mode is enabled (**-x** or **-\-extended-register** command-line arguments are given), then normal single character registers are used *unless* the character immediately following a command that needs a register name is a space (according to **isspace()**) and not a newline (**'\\n'**). In that case, the register name is found according to the regex **\[a-z\]\[a-z0-9\_\]\*** (like bc(1) identifiers), and it is a parse error if the next non-space characters do not match that regex. # RESET When dc(1) encounters an error or a signal that it has a non-default handler for, it resets. This means that several things happen. First, any macros that are executing are stopped and popped off the stack. The behavior is not unlike that of exceptions in programming languages. Then the execution point is set so that any code waiting to execute (after all macros returned) is skipped. Thus, when dc(1) resets, it skips any remaining code waiting to be executed. Then, if it is interactive mode, and the error was not a fatal error (see the **EXIT STATUS** section), it asks for more input; otherwise, it exits with the appropriate return code. # PERFORMANCE Most dc(1) implementations use **char** types to calculate the value of **1** decimal digit at a time, but that can be slow. This dc(1) does something different. It uses large integers to calculate more than **1** decimal digit at a time. If built in a environment where **DC_LONG_BIT** (see the **LIMITS** section) is **64**, then each integer has **9** decimal digits. If built in an environment where **DC_LONG_BIT** is **32** then each integer has **4** decimal digits. This value (the number of decimal digits per large integer) is called **DC_BASE_DIGS**. In addition, this dc(1) uses an even larger integer for overflow checking. This integer type depends on the value of **DC_LONG_BIT**, but is always at least twice as large as the integer type used to store digits. # LIMITS The following are the limits on dc(1): **DC_LONG_BIT** : The number of bits in the **long** type in the environment where dc(1) was built. This determines how many decimal digits can be stored in a single large integer (see the **PERFORMANCE** section). **DC_BASE_DIGS** : The number of decimal digits per large integer (see the **PERFORMANCE** section). Depends on **DC_LONG_BIT**. **DC_BASE_POW** : The max decimal number that each large integer can store (see **DC_BASE_DIGS**) plus **1**. Depends on **DC_BASE_DIGS**. **DC_OVERFLOW_MAX** : The max number that the overflow type (see the **PERFORMANCE** section) can hold. Depends on **DC_LONG_BIT**. **DC_BASE_MAX** : The maximum output base. Set at **DC_BASE_POW**. **DC_DIM_MAX** : The maximum size of arrays. Set at **SIZE_MAX-1**. **DC_SCALE_MAX** : The maximum **scale**. Set at **DC_OVERFLOW_MAX-1**. **DC_STRING_MAX** : The maximum length of strings. Set at **DC_OVERFLOW_MAX-1**. **DC_NAME_MAX** : The maximum length of identifiers. Set at **DC_OVERFLOW_MAX-1**. **DC_NUM_MAX** : The maximum length of a number (in decimal digits), which includes digits after the decimal point. Set at **DC_OVERFLOW_MAX-1**. **DC_RAND_MAX** : The maximum integer (inclusive) returned by the **'** command, if dc(1). Set at **2\^DC_LONG_BIT-1**. Exponent : The maximum allowable exponent (positive or negative). Set at **DC_OVERFLOW_MAX**. Number of vars : The maximum number of vars/arrays. Set at **SIZE_MAX-1**. These limits are meant to be effectively non-existent; the limits are so large (at least on 64-bit machines) that there should not be any point at which they become a problem. In fact, memory should be exhausted before these limits should be hit. # ENVIRONMENT VARIABLES dc(1) recognizes the following environment variables: **DC_ENV_ARGS** : This is another way to give command-line arguments to dc(1). They should be in the same format as all other command-line arguments. These are always processed first, so any files given in **DC_ENV_ARGS** will be processed before arguments and files given on the command-line. This gives the user the ability to set up "standard" options and files to be used at every invocation. The most useful thing for such files to contain would be useful functions that the user might want every time dc(1) runs. Another use would be to use the **-e** option to set **scale** to a value other than **0**. The code that parses **DC_ENV_ARGS** will correctly handle quoted arguments, but it does not understand escape sequences. For example, the string **"/home/gavin/some dc file.dc"** will be correctly parsed, but the string **"/home/gavin/some \"dc\" file.dc"** will include the backslashes. The quote parsing will handle either kind of quotes, **'** or **"**. Thus, if you have a file with any number of single quotes in the name, you can use double quotes as the outside quotes, as in **"some 'dc' file.dc"**, and vice versa if you have a file with double quotes. However, handling a file with both kinds of quotes in **DC_ENV_ARGS** is not supported due to the complexity of the parsing, though such files are still supported on the command-line where the parsing is done by the shell. **DC_LINE_LENGTH** : If this environment variable exists and contains an integer that is greater than **1** and is less than **UINT16_MAX** (**2\^16-1**), dc(1) will output lines to that length, including the backslash newline combo. The default line length is **70**. The special value of **0** will disable line length checking and print numbers without regard to line length and without backslashes and newlines. **DC_SIGINT_RESET** : If dc(1) is not in interactive mode (see the **INTERACTIVE MODE** section), then this environment variable has no effect because dc(1) exits on **SIGINT** when not in interactive mode. However, when dc(1) is in interactive mode, then if this environment variable exists and contains an integer, a non-zero value makes dc(1) reset on **SIGINT**, rather than exit, and zero makes dc(1) exit. If this environment variable exists and is *not* an integer, then dc(1) will exit on **SIGINT**. This environment variable overrides the default, which can be queried with the **-h** or **-\-help** options. **DC_TTY_MODE** : If TTY mode is *not* available (see the **TTY MODE** section), then this environment variable has no effect. However, when TTY mode is available, then if this environment variable exists and contains an integer, then a non-zero value makes dc(1) use TTY mode, and zero makes dc(1) not use TTY mode. This environment variable overrides the default, which can be queried with the **-h** or **-\-help** options. **DC_PROMPT** : If TTY mode is *not* available (see the **TTY MODE** section), then this environment variable has no effect. However, when TTY mode is available, then if this environment variable exists and contains an integer, a non-zero value makes dc(1) use a prompt, and zero or a non-integer makes dc(1) not use a prompt. If this environment variable does not exist and **DC_TTY_MODE** does, then the value of the **DC_TTY_MODE** environment variable is used. This environment variable and the **DC_TTY_MODE** environment variable override the default, which can be queried with the **-h** or **-\-help** options. +**DC_EXPR_EXIT** + +: If any expressions or expression files are given on the command-line with + **-e**, **-\-expression**, **-f**, or **-\-file**, then if this environment + variable exists and contains an integer, a non-zero value makes dc(1) exit + after executing the expressions and expression files, and a non-zero value + makes dc(1) not exit. + + This environment variable overrides the default, which can be queried with + the **-h** or **-\-help** options. + # EXIT STATUS dc(1) returns the following exit statuses: **0** : No error. **1** : A math error occurred. This follows standard practice of using **1** for expected errors, since math errors will happen in the process of normal execution. Math errors include divide by **0**, taking the square root of a negative number, using a negative number as a bound for the pseudo-random number generator, attempting to convert a negative number to a hardware integer, overflow when converting a number to a hardware integer, overflow when calculating the size of a number, and attempting to use a non-integer where an integer is required. Converting to a hardware integer happens for the second operand of the power (**\^**), places (**\@**), left shift (**H**), and right shift (**h**) operators. **2** : A parse error occurred. Parse errors include unexpected **EOF**, using an invalid character, failing to find the end of a string or comment, and using a token where it is invalid. **3** : A runtime error occurred. Runtime errors include assigning an invalid number to any global (**ibase**, **obase**, or **scale**), giving a bad expression to a **read()** call, calling **read()** inside of a **read()** call, type errors (including attempting to execute a number), and attempting an operation when the stack has too few elements. **4** : A fatal error occurred. Fatal errors include memory allocation errors, I/O errors, failing to open files, attempting to use files that do not have only ASCII characters (dc(1) only accepts ASCII characters), attempting to open a directory as a file, and giving invalid command-line options. The exit status **4** is special; when a fatal error occurs, dc(1) always exits and returns **4**, no matter what mode dc(1) is in. The other statuses will only be returned when dc(1) is not in interactive mode (see the **INTERACTIVE MODE** section), since dc(1) resets its state (see the **RESET** section) and accepts more input when one of those errors occurs in interactive mode. This is also the case when interactive mode is forced by the **-i** flag or **-\-interactive** option. These exit statuses allow dc(1) to be used in shell scripting with error checking, and its normal behavior can be forced by using the **-i** flag or **-\-interactive** option. # INTERACTIVE MODE Like bc(1), dc(1) has an interactive mode and a non-interactive mode. Interactive mode is turned on automatically when both **stdin** and **stdout** are hooked to a terminal, but the **-i** flag and **-\-interactive** option can turn it on in other situations. In interactive mode, dc(1) attempts to recover from errors (see the **RESET** section), and in normal execution, flushes **stdout** as soon as execution is done for the current input. dc(1) may also reset on **SIGINT** instead of exit, depending on the contents of, or default for, the **DC_SIGINT_RESET** environment variable (see the **ENVIRONMENT VARIABLES** section). # TTY MODE If **stdin**, **stdout**, and **stderr** are all connected to a TTY, then "TTY mode" is considered to be available, and thus, dc(1) can turn on TTY mode, subject to some settings. If there is the environment variable **DC_TTY_MODE** in the environment (see the **ENVIRONMENT VARIABLES** section), then if that environment variable contains a non-zero integer, dc(1) will turn on TTY mode when **stdin**, **stdout**, and **stderr** are all connected to a TTY. If the **DC_TTY_MODE** environment variable exists but is *not* a non-zero integer, then dc(1) will not turn TTY mode on. If the environment variable **DC_TTY_MODE** does *not* exist, the default setting is used. The default setting can be queried with the **-h** or **-\-help** options. TTY mode is different from interactive mode because interactive mode is required in the [bc(1) specification][1], and interactive mode requires only **stdin** and **stdout** to be connected to a terminal. ## Command-Line History Command-line history is only enabled if TTY mode is, i.e., that **stdin**, **stdout**, and **stderr** are connected to a TTY and the **DC_TTY_MODE** environment variable (see the **ENVIRONMENT VARIABLES** section) and its default do not disable TTY mode. See the **COMMAND LINE HISTORY** section for more information. ## Prompt If TTY mode is available, then a prompt can be enabled. Like TTY mode itself, it can be turned on or off with an environment variable: **DC_PROMPT** (see the **ENVIRONMENT VARIABLES** section). If the environment variable **DC_PROMPT** exists and is a non-zero integer, then the prompt is turned on when **stdin**, **stdout**, and **stderr** are connected to a TTY and the **-P** and **-\-no-prompt** options were not used. The read prompt will be turned on under the same conditions, except that the **-R** and **-\-no-read-prompt** options must also not be used. However, if **DC_PROMPT** does not exist, the prompt can be enabled or disabled with the **DC_TTY_MODE** environment variable, the **-P** and **-\-no-prompt** options, and the **-R** and **-\-no-read-prompt** options. See the **ENVIRONMENT VARIABLES** and **OPTIONS** sections for more details. # SIGNAL HANDLING Sending a **SIGINT** will cause dc(1) to do one of two things. If dc(1) is not in interactive mode (see the **INTERACTIVE MODE** section), or the **DC_SIGINT_RESET** environment variable (see the **ENVIRONMENT VARIABLES** section), or its default, is either not an integer or it is zero, dc(1) will exit. However, if dc(1) is in interactive mode, and the **DC_SIGINT_RESET** or its default is an integer and non-zero, then dc(1) will stop executing the current input and reset (see the **RESET** section) upon receiving a **SIGINT**. Note that "current input" can mean one of two things. If dc(1) is processing input from **stdin** in interactive mode, it will ask for more input. If dc(1) is processing input from a file in interactive mode, it will stop processing the file and start processing the next file, if one exists, or ask for input from **stdin** if no other file exists. This means that if a **SIGINT** is sent to dc(1) as it is executing a file, it can seem as though dc(1) did not respond to the signal since it will immediately start executing the next file. This is by design; most files that users execute when interacting with dc(1) have function definitions, which are quick to parse. If a file takes a long time to execute, there may be a bug in that file. The rest of the files could still be executed without problem, allowing the user to continue. **SIGTERM** and **SIGQUIT** cause dc(1) to clean up and exit, and it uses the default handler for all other signals. The one exception is **SIGHUP**; in that case, and only when dc(1) is in TTY mode (see the **TTY MODE** section), a **SIGHUP** will cause dc(1) to clean up and exit. # COMMAND LINE HISTORY dc(1) supports interactive command-line editing. If dc(1) can be in TTY mode (see the **TTY MODE** section), history can be enabled. This means that command-line history can only be enabled when **stdin**, **stdout**, and **stderr** are all connected to a TTY. Like TTY mode itself, it can be turned on or off with the environment variable **DC_TTY_MODE** (see the **ENVIRONMENT VARIABLES** section). **Note**: tabs are converted to 8 spaces. # LOCALES This dc(1) ships with support for adding error messages for different locales and thus, supports **LC_MESSAGES**. # SEE ALSO bc(1) # STANDARDS The dc(1) utility operators are compliant with the operators in the bc(1) [IEEE Std 1003.1-2017 (“POSIX.1-2017”)][1] specification. # BUGS None are known. Report bugs at https://git.yzena.com/gavin/bc. # AUTHOR Gavin D. Howard and contributors. [1]: https://pubs.opengroup.org/onlinepubs/9699919799/utilities/bc.html diff --git a/contrib/bc/manuals/dc/E.1 b/contrib/bc/manuals/dc/E.1 index 8760477a03ff..a677bcea0c0c 100644 --- a/contrib/bc/manuals/dc/E.1 +++ b/contrib/bc/manuals/dc/E.1 @@ -1,1342 +1,1355 @@ .\" .\" SPDX-License-Identifier: BSD-2-Clause .\" .\" Copyright (c) 2018-2021 Gavin D. Howard and contributors. .\" .\" Redistribution and use in source and binary forms, with or without .\" modification, are permitted provided that the following conditions are met: .\" .\" * Redistributions of source code must retain the above copyright notice, .\" this list of conditions and the following disclaimer. .\" .\" * Redistributions in binary form must reproduce the above copyright notice, .\" this list of conditions and the following disclaimer in the documentation .\" and/or other materials provided with the distribution. .\" .\" THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" .\" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE .\" IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE .\" ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE .\" LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR .\" CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF .\" SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS .\" INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN .\" CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) .\" ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE .\" POSSIBILITY OF SUCH DAMAGE. .\" .TH "DC" "1" "June 2021" "Gavin D. Howard" "General Commands Manual" .SH Name .PP dc - arbitrary-precision decimal reverse-Polish notation calculator .SH SYNOPSIS .PP \f[B]dc\f[R] [\f[B]-hiPRvVx\f[R]] [\f[B]--version\f[R]] [\f[B]--help\f[R]] [\f[B]--interactive\f[R]] [\f[B]--no-prompt\f[R]] [\f[B]--no-read-prompt\f[R]] [\f[B]--extended-register\f[R]] [\f[B]-e\f[R] \f[I]expr\f[R]] [\f[B]--expression\f[R]=\f[I]expr\f[R]\&...] [\f[B]-f\f[R] \f[I]file\f[R]\&...] [\f[B]--file\f[R]=\f[I]file\f[R]\&...] [\f[I]file\f[R]\&...] .SH DESCRIPTION .PP dc(1) is an arbitrary-precision calculator. It uses a stack (reverse Polish notation) to store numbers and results of computations. Arithmetic operations pop arguments off of the stack and push the results. .PP If no files are given on the command-line, then dc(1) reads from \f[B]stdin\f[R] (see the \f[B]STDIN\f[R] section). Otherwise, those files are processed, and dc(1) will then exit. .PP If a user wants to set up a standard environment, they can use \f[B]DC_ENV_ARGS\f[R] (see the \f[B]ENVIRONMENT VARIABLES\f[R] section). For example, if a user wants the \f[B]scale\f[R] always set to \f[B]10\f[R], they can set \f[B]DC_ENV_ARGS\f[R] to \f[B]-e 10k\f[R], and this dc(1) will always start with a \f[B]scale\f[R] of \f[B]10\f[R]. .SH OPTIONS .PP The following are the options that dc(1) accepts. .TP \f[B]-h\f[R], \f[B]--help\f[R] Prints a usage message and quits. .TP \f[B]-v\f[R], \f[B]-V\f[R], \f[B]--version\f[R] Print the version information (copyright header) and exit. .TP \f[B]-i\f[R], \f[B]--interactive\f[R] Forces interactive mode. (See the \f[B]INTERACTIVE MODE\f[R] section.) .RS .PP This is a \f[B]non-portable extension\f[R]. .RE .TP \f[B]-L\f[R], \f[B]--no-line-length\f[R] Disables line length checking and prints numbers without backslashes and newlines. In other words, this option sets \f[B]BC_LINE_LENGTH\f[R] to \f[B]0\f[R] (see the \f[B]ENVIRONMENT VARIABLES\f[R] section). .RS .PP This is a \f[B]non-portable extension\f[R]. .RE .TP \f[B]-P\f[R], \f[B]--no-prompt\f[R] Disables the prompt in TTY mode. (The prompt is only enabled in TTY mode. See the \f[B]TTY MODE\f[R] section.) This is mostly for those users that do not want a prompt or are not used to having them in dc(1). Most of those users would want to put this option in \f[B]DC_ENV_ARGS\f[R]. .RS .PP These options override the \f[B]DC_PROMPT\f[R] and \f[B]DC_TTY_MODE\f[R] environment variables (see the \f[B]ENVIRONMENT VARIABLES\f[R] section). .PP This is a \f[B]non-portable extension\f[R]. .RE .TP \f[B]-R\f[R], \f[B]--no-read-prompt\f[R] Disables the read prompt in TTY mode. (The read prompt is only enabled in TTY mode. See the \f[B]TTY MODE\f[R] section.) This is mostly for those users that do not want a read prompt or are not used to having them in dc(1). Most of those users would want to put this option in \f[B]BC_ENV_ARGS\f[R] (see the \f[B]ENVIRONMENT VARIABLES\f[R] section). This option is also useful in hash bang lines of dc(1) scripts that prompt for user input. .RS .PP This option does not disable the regular prompt because the read prompt is only used when the \f[B]?\f[R] command is used. .PP These options \f[I]do\f[R] override the \f[B]DC_PROMPT\f[R] and \f[B]DC_TTY_MODE\f[R] environment variables (see the \f[B]ENVIRONMENT VARIABLES\f[R] section), but only for the read prompt. .PP This is a \f[B]non-portable extension\f[R]. .RE .TP \f[B]-x\f[R] \f[B]--extended-register\f[R] Enables extended register mode. See the \f[I]Extended Register Mode\f[R] subsection of the \f[B]REGISTERS\f[R] section for more information. .RS .PP This is a \f[B]non-portable extension\f[R]. .RE .TP \f[B]-z\f[R], \f[B]--leading-zeroes\f[R] Makes bc(1) print all numbers greater than \f[B]-1\f[R] and less than \f[B]1\f[R], and not equal to \f[B]0\f[R], with a leading zero. .RS .PP This can be set for individual numbers with the \f[B]plz(x)\f[R], plznl(x)**, \f[B]pnlz(x)\f[R], and \f[B]pnlznl(x)\f[R] functions in the extended math library (see the \f[B]LIBRARY\f[R] section). .PP This is a \f[B]non-portable extension\f[R]. .RE .TP \f[B]-e\f[R] \f[I]expr\f[R], \f[B]--expression\f[R]=\f[I]expr\f[R] Evaluates \f[I]expr\f[R]. If multiple expressions are given, they are evaluated in order. If files are given as well (see below), the expressions and files are evaluated in the order given. This means that if a file is given before an expression, the file is read in and evaluated first. .RS .PP If this option is given on the command-line (i.e., not in \f[B]DC_ENV_ARGS\f[R], see the \f[B]ENVIRONMENT VARIABLES\f[R] section), then after processing all expressions and files, dc(1) will exit, unless \f[B]-\f[R] (\f[B]stdin\f[R]) was given as an argument at least once to \f[B]-f\f[R] or \f[B]--file\f[R], whether on the command-line or in \f[B]DC_ENV_ARGS\f[R]. However, if any other \f[B]-e\f[R], \f[B]--expression\f[R], \f[B]-f\f[R], or \f[B]--file\f[R] arguments are given after \f[B]-f-\f[R] or equivalent is given, dc(1) will give a fatal error and exit. .PP This is a \f[B]non-portable extension\f[R]. .RE .TP \f[B]-f\f[R] \f[I]file\f[R], \f[B]--file\f[R]=\f[I]file\f[R] Reads in \f[I]file\f[R] and evaluates it, line by line, as though it were read through \f[B]stdin\f[R]. If expressions are also given (see above), the expressions are evaluated in the order given. .RS .PP If this option is given on the command-line (i.e., not in \f[B]DC_ENV_ARGS\f[R], see the \f[B]ENVIRONMENT VARIABLES\f[R] section), then after processing all expressions and files, dc(1) will exit, unless \f[B]-\f[R] (\f[B]stdin\f[R]) was given as an argument at least once to \f[B]-f\f[R] or \f[B]--file\f[R]. However, if any other \f[B]-e\f[R], \f[B]--expression\f[R], \f[B]-f\f[R], or \f[B]--file\f[R] arguments are given after \f[B]-f-\f[R] or equivalent is given, dc(1) will give a fatal error and exit. .PP This is a \f[B]non-portable extension\f[R]. .RE .PP All long options are \f[B]non-portable extensions\f[R]. .SH STDIN .PP If no files are given on the command-line and no files or expressions are given by the \f[B]-f\f[R], \f[B]--file\f[R], \f[B]-e\f[R], or \f[B]--expression\f[R] options, then dc(1) read from \f[B]stdin\f[R]. .PP However, there is a caveat to this. .PP First, \f[B]stdin\f[R] is evaluated a line at a time. The only exception to this is if a string has been finished, but not ended. This means that, except for escaped brackets, all brackets must be balanced before dc(1) parses and executes. .SH STDOUT .PP Any non-error output is written to \f[B]stdout\f[R]. In addition, if history (see the \f[B]HISTORY\f[R] section) and the prompt (see the \f[B]TTY MODE\f[R] section) are enabled, both are output to \f[B]stdout\f[R]. .PP \f[B]Note\f[R]: Unlike other dc(1) implementations, this dc(1) will issue a fatal error (see the \f[B]EXIT STATUS\f[R] section) if it cannot write to \f[B]stdout\f[R], so if \f[B]stdout\f[R] is closed, as in \f[B]dc >&-\f[R], it will quit with an error. This is done so that dc(1) can report problems when \f[B]stdout\f[R] is redirected to a file. .PP If there are scripts that depend on the behavior of other dc(1) implementations, it is recommended that those scripts be changed to redirect \f[B]stdout\f[R] to \f[B]/dev/null\f[R]. .SH STDERR .PP Any error output is written to \f[B]stderr\f[R]. .PP \f[B]Note\f[R]: Unlike other dc(1) implementations, this dc(1) will issue a fatal error (see the \f[B]EXIT STATUS\f[R] section) if it cannot write to \f[B]stderr\f[R], so if \f[B]stderr\f[R] is closed, as in \f[B]dc 2>&-\f[R], it will quit with an error. This is done so that dc(1) can exit with an error code when \f[B]stderr\f[R] is redirected to a file. .PP If there are scripts that depend on the behavior of other dc(1) implementations, it is recommended that those scripts be changed to redirect \f[B]stderr\f[R] to \f[B]/dev/null\f[R]. .SH SYNTAX .PP Each item in the input source code, either a number (see the \f[B]NUMBERS\f[R] section) or a command (see the \f[B]COMMANDS\f[R] section), is processed and executed, in order. Input is processed immediately when entered. .PP \f[B]ibase\f[R] is a register (see the \f[B]REGISTERS\f[R] section) that determines how to interpret constant numbers. It is the \[lq]input\[rq] base, or the number base used for interpreting input numbers. \f[B]ibase\f[R] is initially \f[B]10\f[R]. The max allowable value for \f[B]ibase\f[R] is \f[B]16\f[R]. The min allowable value for \f[B]ibase\f[R] is \f[B]2\f[R]. The max allowable value for \f[B]ibase\f[R] can be queried in dc(1) programs with the \f[B]T\f[R] command. .PP \f[B]obase\f[R] is a register (see the \f[B]REGISTERS\f[R] section) that determines how to output results. It is the \[lq]output\[rq] base, or the number base used for outputting numbers. \f[B]obase\f[R] is initially \f[B]10\f[R]. The max allowable value for \f[B]obase\f[R] is \f[B]DC_BASE_MAX\f[R] and can be queried with the \f[B]U\f[R] command. The min allowable value for \f[B]obase\f[R] is \f[B]2\f[R]. Values are output in the specified base. .PP The \f[I]scale\f[R] of an expression is the number of digits in the result of the expression right of the decimal point, and \f[B]scale\f[R] is a register (see the \f[B]REGISTERS\f[R] section) that sets the precision of any operations (with exceptions). \f[B]scale\f[R] is initially \f[B]0\f[R]. \f[B]scale\f[R] cannot be negative. The max allowable value for \f[B]scale\f[R] can be queried in dc(1) programs with the \f[B]V\f[R] command. .SS Comments .PP Comments go from \f[B]#\f[R] until, and not including, the next newline. This is a \f[B]non-portable extension\f[R]. .SH NUMBERS .PP Numbers are strings made up of digits, uppercase letters up to \f[B]F\f[R], and at most \f[B]1\f[R] period for a radix. Numbers can have up to \f[B]DC_NUM_MAX\f[R] digits. Uppercase letters are equal to \f[B]9\f[R] + their position in the alphabet (i.e., \f[B]A\f[R] equals \f[B]10\f[R], or \f[B]9+1\f[R]). If a digit or letter makes no sense with the current value of \f[B]ibase\f[R], they are set to the value of the highest valid digit in \f[B]ibase\f[R]. .PP Single-character numbers (i.e., \f[B]A\f[R] alone) take the value that they would have if they were valid digits, regardless of the value of \f[B]ibase\f[R]. This means that \f[B]A\f[R] alone always equals decimal \f[B]10\f[R] and \f[B]F\f[R] alone always equals decimal \f[B]15\f[R]. .SH COMMANDS .PP The valid commands are listed below. .SS Printing .PP These commands are used for printing. .TP \f[B]p\f[R] Prints the value on top of the stack, whether number or string, and prints a newline after. .RS .PP This does not alter the stack. .RE .TP \f[B]n\f[R] Prints the value on top of the stack, whether number or string, and pops it off of the stack. .TP \f[B]P\f[R] Pops a value off the stack. .RS .PP If the value is a number, it is truncated and the absolute value of the result is printed as though \f[B]obase\f[R] is \f[B]256\f[R] and each digit is interpreted as an 8-bit ASCII character, making it a byte stream. .PP If the value is a string, it is printed without a trailing newline. .PP This is a \f[B]non-portable extension\f[R]. .RE .TP \f[B]f\f[R] Prints the entire contents of the stack, in order from newest to oldest, without altering anything. .RS .PP Users should use this command when they get lost. .RE .SS Arithmetic .PP These are the commands used for arithmetic. .TP \f[B]+\f[R] The top two values are popped off the stack, added, and the result is pushed onto the stack. The \f[I]scale\f[R] of the result is equal to the max \f[I]scale\f[R] of both operands. .TP \f[B]-\f[R] The top two values are popped off the stack, subtracted, and the result is pushed onto the stack. The \f[I]scale\f[R] of the result is equal to the max \f[I]scale\f[R] of both operands. .TP \f[B]*\f[R] The top two values are popped off the stack, multiplied, and the result is pushed onto the stack. If \f[B]a\f[R] is the \f[I]scale\f[R] of the first expression and \f[B]b\f[R] is the \f[I]scale\f[R] of the second expression, the \f[I]scale\f[R] of the result is equal to \f[B]min(a+b,max(scale,a,b))\f[R] where \f[B]min()\f[R] and \f[B]max()\f[R] return the obvious values. .TP \f[B]/\f[R] The top two values are popped off the stack, divided, and the result is pushed onto the stack. The \f[I]scale\f[R] of the result is equal to \f[B]scale\f[R]. .RS .PP The first value popped off of the stack must be non-zero. .RE .TP \f[B]%\f[R] The top two values are popped off the stack, remaindered, and the result is pushed onto the stack. .RS .PP Remaindering is equivalent to 1) Computing \f[B]a/b\f[R] to current \f[B]scale\f[R], and 2) Using the result of step 1 to calculate \f[B]a-(a/b)*b\f[R] to \f[I]scale\f[R] \f[B]max(scale+scale(b),scale(a))\f[R]. .PP The first value popped off of the stack must be non-zero. .RE .TP \f[B]\[ti]\f[R] The top two values are popped off the stack, divided and remaindered, and the results (divided first, remainder second) are pushed onto the stack. This is equivalent to \f[B]x y / x y %\f[R] except that \f[B]x\f[R] and \f[B]y\f[R] are only evaluated once. .RS .PP The first value popped off of the stack must be non-zero. .PP This is a \f[B]non-portable extension\f[R]. .RE .TP \f[B]\[ha]\f[R] The top two values are popped off the stack, the second is raised to the power of the first, and the result is pushed onto the stack. The \f[I]scale\f[R] of the result is equal to \f[B]scale\f[R]. .RS .PP The first value popped off of the stack must be an integer, and if that value is negative, the second value popped off of the stack must be non-zero. .RE .TP \f[B]v\f[R] The top value is popped off the stack, its square root is computed, and the result is pushed onto the stack. The \f[I]scale\f[R] of the result is equal to \f[B]scale\f[R]. .RS .PP The value popped off of the stack must be non-negative. .RE .TP \f[B]_\f[R] If this command \f[I]immediately\f[R] precedes a number (i.e., no spaces or other commands), then that number is input as a negative number. .RS .PP Otherwise, the top value on the stack is popped and copied, and the copy is negated and pushed onto the stack. This behavior without a number is a \f[B]non-portable extension\f[R]. .RE .TP \f[B]b\f[R] The top value is popped off the stack, and if it is zero, it is pushed back onto the stack. Otherwise, its absolute value is pushed onto the stack. .RS .PP This is a \f[B]non-portable extension\f[R]. .RE .TP \f[B]|\f[R] The top three values are popped off the stack, a modular exponentiation is computed, and the result is pushed onto the stack. .RS .PP The first value popped is used as the reduction modulus and must be an integer and non-zero. The second value popped is used as the exponent and must be an integer and non-negative. The third value popped is the base and must be an integer. .PP This is a \f[B]non-portable extension\f[R]. .RE .TP \f[B]G\f[R] The top two values are popped off of the stack, they are compared, and a \f[B]1\f[R] is pushed if they are equal, or \f[B]0\f[R] otherwise. .RS .PP This is a \f[B]non-portable extension\f[R]. .RE .TP \f[B]N\f[R] The top value is popped off of the stack, and if it a \f[B]0\f[R], a \f[B]1\f[R] is pushed; otherwise, a \f[B]0\f[R] is pushed. .RS .PP This is a \f[B]non-portable extension\f[R]. .RE .TP \f[B](\f[R] The top two values are popped off of the stack, they are compared, and a \f[B]1\f[R] is pushed if the first is less than the second, or \f[B]0\f[R] otherwise. .RS .PP This is a \f[B]non-portable extension\f[R]. .RE .TP \f[B]{\f[R] The top two values are popped off of the stack, they are compared, and a \f[B]1\f[R] is pushed if the first is less than or equal to the second, or \f[B]0\f[R] otherwise. .RS .PP This is a \f[B]non-portable extension\f[R]. .RE .TP \f[B])\f[R] The top two values are popped off of the stack, they are compared, and a \f[B]1\f[R] is pushed if the first is greater than the second, or \f[B]0\f[R] otherwise. .RS .PP This is a \f[B]non-portable extension\f[R]. .RE .TP \f[B]}\f[R] The top two values are popped off of the stack, they are compared, and a \f[B]1\f[R] is pushed if the first is greater than or equal to the second, or \f[B]0\f[R] otherwise. .RS .PP This is a \f[B]non-portable extension\f[R]. .RE .TP \f[B]M\f[R] The top two values are popped off of the stack. If they are both non-zero, a \f[B]1\f[R] is pushed onto the stack. If either of them is zero, or both of them are, then a \f[B]0\f[R] is pushed onto the stack. .RS .PP This is like the \f[B]&&\f[R] operator in bc(1), and it is \f[I]not\f[R] a short-circuit operator. .PP This is a \f[B]non-portable extension\f[R]. .RE .TP \f[B]m\f[R] The top two values are popped off of the stack. If at least one of them is non-zero, a \f[B]1\f[R] is pushed onto the stack. If both of them are zero, then a \f[B]0\f[R] is pushed onto the stack. .RS .PP This is like the \f[B]||\f[R] operator in bc(1), and it is \f[I]not\f[R] a short-circuit operator. .PP This is a \f[B]non-portable extension\f[R]. .RE .SS Stack Control .PP These commands control the stack. .TP \f[B]c\f[R] Removes all items from (\[lq]clears\[rq]) the stack. .TP \f[B]d\f[R] Copies the item on top of the stack (\[lq]duplicates\[rq]) and pushes the copy onto the stack. .TP \f[B]r\f[R] Swaps (\[lq]reverses\[rq]) the two top items on the stack. .TP \f[B]R\f[R] Pops (\[lq]removes\[rq]) the top value from the stack. .SS Register Control .PP These commands control registers (see the \f[B]REGISTERS\f[R] section). .TP \f[B]s\f[R]\f[I]r\f[R] Pops the value off the top of the stack and stores it into register \f[I]r\f[R]. .TP \f[B]l\f[R]\f[I]r\f[R] Copies the value in register \f[I]r\f[R] and pushes it onto the stack. This does not alter the contents of \f[I]r\f[R]. .TP \f[B]S\f[R]\f[I]r\f[R] Pops the value off the top of the (main) stack and pushes it onto the stack of register \f[I]r\f[R]. The previous value of the register becomes inaccessible. .TP \f[B]L\f[R]\f[I]r\f[R] Pops the value off the top of the stack for register \f[I]r\f[R] and push it onto the main stack. The previous value in the stack for register \f[I]r\f[R], if any, is now accessible via the \f[B]l\f[R]\f[I]r\f[R] command. .SS Parameters .PP These commands control the values of \f[B]ibase\f[R], \f[B]obase\f[R], and \f[B]scale\f[R]. Also see the \f[B]SYNTAX\f[R] section. .TP \f[B]i\f[R] Pops the value off of the top of the stack and uses it to set \f[B]ibase\f[R], which must be between \f[B]2\f[R] and \f[B]16\f[R], inclusive. .RS .PP If the value on top of the stack has any \f[I]scale\f[R], the \f[I]scale\f[R] is ignored. .RE .TP \f[B]o\f[R] Pops the value off of the top of the stack and uses it to set \f[B]obase\f[R], which must be between \f[B]2\f[R] and \f[B]DC_BASE_MAX\f[R], inclusive (see the \f[B]LIMITS\f[R] section). .RS .PP If the value on top of the stack has any \f[I]scale\f[R], the \f[I]scale\f[R] is ignored. .RE .TP \f[B]k\f[R] Pops the value off of the top of the stack and uses it to set \f[B]scale\f[R], which must be non-negative. .RS .PP If the value on top of the stack has any \f[I]scale\f[R], the \f[I]scale\f[R] is ignored. .RE .TP \f[B]I\f[R] Pushes the current value of \f[B]ibase\f[R] onto the main stack. .TP \f[B]O\f[R] Pushes the current value of \f[B]obase\f[R] onto the main stack. .TP \f[B]K\f[R] Pushes the current value of \f[B]scale\f[R] onto the main stack. .TP \f[B]T\f[R] Pushes the maximum allowable value of \f[B]ibase\f[R] onto the main stack. .RS .PP This is a \f[B]non-portable extension\f[R]. .RE .TP \f[B]U\f[R] Pushes the maximum allowable value of \f[B]obase\f[R] onto the main stack. .RS .PP This is a \f[B]non-portable extension\f[R]. .RE .TP \f[B]V\f[R] Pushes the maximum allowable value of \f[B]scale\f[R] onto the main stack. .RS .PP This is a \f[B]non-portable extension\f[R]. .RE .SS Strings .PP The following commands control strings. .PP dc(1) can work with both numbers and strings, and registers (see the \f[B]REGISTERS\f[R] section) can hold both strings and numbers. dc(1) always knows whether the contents of a register are a string or a number. .PP While arithmetic operations have to have numbers, and will print an error if given a string, other commands accept strings. .PP Strings can also be executed as macros. For example, if the string \f[B][1pR]\f[R] is executed as a macro, then the code \f[B]1pR\f[R] is executed, meaning that the \f[B]1\f[R] will be printed with a newline after and then popped from the stack. .TP \f[B][\f[R]\f[I]characters\f[R]\f[B]]\f[R] Makes a string containing \f[I]characters\f[R] and pushes it onto the stack. .RS .PP If there are brackets (\f[B][\f[R] and \f[B]]\f[R]) in the string, then they must be balanced. Unbalanced brackets can be escaped using a backslash (\f[B]\[rs]\f[R]) character. .PP If there is a backslash character in the string, the character after it (even another backslash) is put into the string verbatim, but the (first) backslash is not. .RE .TP \f[B]a\f[R] The value on top of the stack is popped. .RS .PP If it is a number, it is truncated and its absolute value is taken. The result mod \f[B]256\f[R] is calculated. If that result is \f[B]0\f[R], push an empty string; otherwise, push a one-character string where the character is the result of the mod interpreted as an ASCII character. .PP If it is a string, then a new string is made. If the original string is empty, the new string is empty. If it is not, then the first character of the original string is used to create the new string as a one-character string. The new string is then pushed onto the stack. .PP This is a \f[B]non-portable extension\f[R]. .RE .TP \f[B]x\f[R] Pops a value off of the top of the stack. .RS .PP If it is a number, it is pushed back onto the stack. .PP If it is a string, it is executed as a macro. .PP This behavior is the norm whenever a macro is executed, whether by this command or by the conditional execution commands below. .RE .TP \f[B]>\f[R]\f[I]r\f[R] Pops two values off of the stack that must be numbers and compares them. If the first value is greater than the second, then the contents of register \f[I]r\f[R] are executed. .RS .PP For example, \f[B]0 1>a\f[R] will execute the contents of register \f[B]a\f[R], and \f[B]1 0>a\f[R] will not. .PP If either or both of the values are not numbers, dc(1) will raise an error and reset (see the \f[B]RESET\f[R] section). .RE .TP \f[B]>\f[R]\f[I]r\f[R]\f[B]e\f[R]\f[I]s\f[R] Like the above, but will execute register \f[I]s\f[R] if the comparison fails. .RS .PP If either or both of the values are not numbers, dc(1) will raise an error and reset (see the \f[B]RESET\f[R] section). .PP This is a \f[B]non-portable extension\f[R]. .RE .TP \f[B]!>\f[R]\f[I]r\f[R] Pops two values off of the stack that must be numbers and compares them. If the first value is not greater than the second (less than or equal to), then the contents of register \f[I]r\f[R] are executed. .RS .PP If either or both of the values are not numbers, dc(1) will raise an error and reset (see the \f[B]RESET\f[R] section). .RE .TP \f[B]!>\f[R]\f[I]r\f[R]\f[B]e\f[R]\f[I]s\f[R] Like the above, but will execute register \f[I]s\f[R] if the comparison fails. .RS .PP If either or both of the values are not numbers, dc(1) will raise an error and reset (see the \f[B]RESET\f[R] section). .PP This is a \f[B]non-portable extension\f[R]. .RE .TP \f[B]<\f[R]\f[I]r\f[R] Pops two values off of the stack that must be numbers and compares them. If the first value is less than the second, then the contents of register \f[I]r\f[R] are executed. .RS .PP If either or both of the values are not numbers, dc(1) will raise an error and reset (see the \f[B]RESET\f[R] section). .RE .TP \f[B]<\f[R]\f[I]r\f[R]\f[B]e\f[R]\f[I]s\f[R] Like the above, but will execute register \f[I]s\f[R] if the comparison fails. .RS .PP If either or both of the values are not numbers, dc(1) will raise an error and reset (see the \f[B]RESET\f[R] section). .PP This is a \f[B]non-portable extension\f[R]. .RE .TP \f[B]!<\f[R]\f[I]r\f[R] Pops two values off of the stack that must be numbers and compares them. If the first value is not less than the second (greater than or equal to), then the contents of register \f[I]r\f[R] are executed. .RS .PP If either or both of the values are not numbers, dc(1) will raise an error and reset (see the \f[B]RESET\f[R] section). .RE .TP \f[B]!<\f[R]\f[I]r\f[R]\f[B]e\f[R]\f[I]s\f[R] Like the above, but will execute register \f[I]s\f[R] if the comparison fails. .RS .PP If either or both of the values are not numbers, dc(1) will raise an error and reset (see the \f[B]RESET\f[R] section). .PP This is a \f[B]non-portable extension\f[R]. .RE .TP \f[B]=\f[R]\f[I]r\f[R] Pops two values off of the stack that must be numbers and compares them. If the first value is equal to the second, then the contents of register \f[I]r\f[R] are executed. .RS .PP If either or both of the values are not numbers, dc(1) will raise an error and reset (see the \f[B]RESET\f[R] section). .RE .TP \f[B]=\f[R]\f[I]r\f[R]\f[B]e\f[R]\f[I]s\f[R] Like the above, but will execute register \f[I]s\f[R] if the comparison fails. .RS .PP If either or both of the values are not numbers, dc(1) will raise an error and reset (see the \f[B]RESET\f[R] section). .PP This is a \f[B]non-portable extension\f[R]. .RE .TP \f[B]!=\f[R]\f[I]r\f[R] Pops two values off of the stack that must be numbers and compares them. If the first value is not equal to the second, then the contents of register \f[I]r\f[R] are executed. .RS .PP If either or both of the values are not numbers, dc(1) will raise an error and reset (see the \f[B]RESET\f[R] section). .RE .TP \f[B]!=\f[R]\f[I]r\f[R]\f[B]e\f[R]\f[I]s\f[R] Like the above, but will execute register \f[I]s\f[R] if the comparison fails. .RS .PP If either or both of the values are not numbers, dc(1) will raise an error and reset (see the \f[B]RESET\f[R] section). .PP This is a \f[B]non-portable extension\f[R]. .RE .TP \f[B]?\f[R] Reads a line from the \f[B]stdin\f[R] and executes it. This is to allow macros to request input from users. .TP \f[B]q\f[R] During execution of a macro, this exits the execution of that macro and the execution of the macro that executed it. If there are no macros, or only one macro executing, dc(1) exits. .TP \f[B]Q\f[R] Pops a value from the stack which must be non-negative and is used the number of macro executions to pop off of the execution stack. If the number of levels to pop is greater than the number of executing macros, dc(1) exits. .TP \f[B],\f[R] Pushes the depth of the execution stack onto the stack. The execution stack is the stack of string executions. The number that is pushed onto the stack is exactly as many as is needed to make dc(1) exit with the \f[B]Q\f[R] command, so the sequence \f[B],Q\f[R] will make dc(1) exit. .SS Status .PP These commands query status of the stack or its top value. .TP \f[B]Z\f[R] Pops a value off of the stack. .RS .PP If it is a number, calculates the number of significant decimal digits it has and pushes the result. It will push \f[B]1\f[R] if the argument is \f[B]0\f[R] with no decimal places. .PP If it is a string, pushes the number of characters the string has. .RE .TP \f[B]X\f[R] Pops a value off of the stack. .RS .PP If it is a number, pushes the \f[I]scale\f[R] of the value onto the stack. .PP If it is a string, pushes \f[B]0\f[R]. .RE .TP \f[B]z\f[R] Pushes the current depth of the stack (before execution of this command) onto the stack. .TP \f[B]y\f[R]\f[I]r\f[R] Pushes the current stack depth of the register \f[I]r\f[R] onto the main stack. .RS .PP Because each register has a depth of \f[B]1\f[R] (with the value \f[B]0\f[R] in the top item) when dc(1) starts, dc(1) requires that each register\[cq]s stack must always have at least one item; dc(1) will give an error and reset otherwise (see the \f[B]RESET\f[R] section). This means that this command will never push \f[B]0\f[R]. .PP This is a \f[B]non-portable extension\f[R]. .RE .SS Arrays .PP These commands manipulate arrays. .TP \f[B]:\f[R]\f[I]r\f[R] Pops the top two values off of the stack. The second value will be stored in the array \f[I]r\f[R] (see the \f[B]REGISTERS\f[R] section), indexed by the first value. .TP \f[B];\f[R]\f[I]r\f[R] Pops the value on top of the stack and uses it as an index into the array \f[I]r\f[R]. The selected value is then pushed onto the stack. .TP \f[B]Y\f[R]\f[I]r\f[R] Pushes the length of the array \f[I]r\f[R] onto the stack. .RS .PP This is a \f[B]non-portable extension\f[R]. .RE .SS Global Settings .PP These commands retrieve global settings. These are the only commands that require multiple specific characters, and all of them begin with the letter \f[B]g\f[R]. Only the characters below are allowed after the character \f[B]g\f[R]; any other character produces a parse error (see the \f[B]ERRORS\f[R] section). .TP \f[B]gl\f[R] Pushes the line length set by \f[B]DC_LINE_LENGTH\f[R] (see the \f[B]ENVIRONMENT VARIABLES\f[R] section) onto the stack. .TP \f[B]gz\f[R] Pushes \f[B]0\f[R] onto the stack if the leading zero setting has not been enabled with the \f[B]-z\f[R] or \f[B]--leading-zeroes\f[R] options (see the \f[B]OPTIONS\f[R] section), non-zero otherwise. .SH REGISTERS .PP Registers are names that can store strings, numbers, and arrays. (Number/string registers do not interfere with array registers.) .PP Each register is also its own stack, so the current register value is the top of the stack for the register. All registers, when first referenced, have one value (\f[B]0\f[R]) in their stack, and it is a runtime error to attempt to pop that item off of the register stack. .PP In non-extended register mode, a register name is just the single character that follows any command that needs a register name. The only exceptions are: a newline (\f[B]`\[rs]n'\f[R]) and a left bracket (\f[B]`['\f[R]); it is a parse error for a newline or a left bracket to be used as a register name. .SS Extended Register Mode .PP Unlike most other dc(1) implentations, this dc(1) provides nearly unlimited amounts of registers, if extended register mode is enabled. .PP If extended register mode is enabled (\f[B]-x\f[R] or \f[B]--extended-register\f[R] command-line arguments are given), then normal single character registers are used \f[I]unless\f[R] the character immediately following a command that needs a register name is a space (according to \f[B]isspace()\f[R]) and not a newline (\f[B]`\[rs]n'\f[R]). .PP In that case, the register name is found according to the regex \f[B][a-z][a-z0-9_]*\f[R] (like bc(1) identifiers), and it is a parse error if the next non-space characters do not match that regex. .SH RESET .PP When dc(1) encounters an error or a signal that it has a non-default handler for, it resets. This means that several things happen. .PP First, any macros that are executing are stopped and popped off the stack. The behavior is not unlike that of exceptions in programming languages. Then the execution point is set so that any code waiting to execute (after all macros returned) is skipped. .PP Thus, when dc(1) resets, it skips any remaining code waiting to be executed. Then, if it is interactive mode, and the error was not a fatal error (see the \f[B]EXIT STATUS\f[R] section), it asks for more input; otherwise, it exits with the appropriate return code. .SH PERFORMANCE .PP Most dc(1) implementations use \f[B]char\f[R] types to calculate the value of \f[B]1\f[R] decimal digit at a time, but that can be slow. This dc(1) does something different. .PP It uses large integers to calculate more than \f[B]1\f[R] decimal digit at a time. If built in a environment where \f[B]DC_LONG_BIT\f[R] (see the \f[B]LIMITS\f[R] section) is \f[B]64\f[R], then each integer has \f[B]9\f[R] decimal digits. If built in an environment where \f[B]DC_LONG_BIT\f[R] is \f[B]32\f[R] then each integer has \f[B]4\f[R] decimal digits. This value (the number of decimal digits per large integer) is called \f[B]DC_BASE_DIGS\f[R]. .PP In addition, this dc(1) uses an even larger integer for overflow checking. This integer type depends on the value of \f[B]DC_LONG_BIT\f[R], but is always at least twice as large as the integer type used to store digits. .SH LIMITS .PP The following are the limits on dc(1): .TP \f[B]DC_LONG_BIT\f[R] The number of bits in the \f[B]long\f[R] type in the environment where dc(1) was built. This determines how many decimal digits can be stored in a single large integer (see the \f[B]PERFORMANCE\f[R] section). .TP \f[B]DC_BASE_DIGS\f[R] The number of decimal digits per large integer (see the \f[B]PERFORMANCE\f[R] section). Depends on \f[B]DC_LONG_BIT\f[R]. .TP \f[B]DC_BASE_POW\f[R] The max decimal number that each large integer can store (see \f[B]DC_BASE_DIGS\f[R]) plus \f[B]1\f[R]. Depends on \f[B]DC_BASE_DIGS\f[R]. .TP \f[B]DC_OVERFLOW_MAX\f[R] The max number that the overflow type (see the \f[B]PERFORMANCE\f[R] section) can hold. Depends on \f[B]DC_LONG_BIT\f[R]. .TP \f[B]DC_BASE_MAX\f[R] The maximum output base. Set at \f[B]DC_BASE_POW\f[R]. .TP \f[B]DC_DIM_MAX\f[R] The maximum size of arrays. Set at \f[B]SIZE_MAX-1\f[R]. .TP \f[B]DC_SCALE_MAX\f[R] The maximum \f[B]scale\f[R]. Set at \f[B]DC_OVERFLOW_MAX-1\f[R]. .TP \f[B]DC_STRING_MAX\f[R] The maximum length of strings. Set at \f[B]DC_OVERFLOW_MAX-1\f[R]. .TP \f[B]DC_NAME_MAX\f[R] The maximum length of identifiers. Set at \f[B]DC_OVERFLOW_MAX-1\f[R]. .TP \f[B]DC_NUM_MAX\f[R] The maximum length of a number (in decimal digits), which includes digits after the decimal point. Set at \f[B]DC_OVERFLOW_MAX-1\f[R]. .TP Exponent The maximum allowable exponent (positive or negative). Set at \f[B]DC_OVERFLOW_MAX\f[R]. .TP Number of vars The maximum number of vars/arrays. Set at \f[B]SIZE_MAX-1\f[R]. .PP These limits are meant to be effectively non-existent; the limits are so large (at least on 64-bit machines) that there should not be any point at which they become a problem. In fact, memory should be exhausted before these limits should be hit. .SH ENVIRONMENT VARIABLES .PP dc(1) recognizes the following environment variables: .TP \f[B]DC_ENV_ARGS\f[R] This is another way to give command-line arguments to dc(1). They should be in the same format as all other command-line arguments. These are always processed first, so any files given in \f[B]DC_ENV_ARGS\f[R] will be processed before arguments and files given on the command-line. This gives the user the ability to set up \[lq]standard\[rq] options and files to be used at every invocation. The most useful thing for such files to contain would be useful functions that the user might want every time dc(1) runs. Another use would be to use the \f[B]-e\f[R] option to set \f[B]scale\f[R] to a value other than \f[B]0\f[R]. .RS .PP The code that parses \f[B]DC_ENV_ARGS\f[R] will correctly handle quoted arguments, but it does not understand escape sequences. For example, the string \f[B]\[lq]/home/gavin/some dc file.dc\[rq]\f[R] will be correctly parsed, but the string \f[B]\[lq]/home/gavin/some \[dq]dc\[dq] file.dc\[rq]\f[R] will include the backslashes. .PP The quote parsing will handle either kind of quotes, \f[B]\[cq]\f[R] or \f[B]\[lq]\f[R]. Thus, if you have a file with any number of single quotes in the name, you can use double quotes as the outside quotes, as in \f[B]\[lq]some `dc' file.dc\[rq]\f[R], and vice versa if you have a file with double quotes. However, handling a file with both kinds of quotes in \f[B]DC_ENV_ARGS\f[R] is not supported due to the complexity of the parsing, though such files are still supported on the command-line where the parsing is done by the shell. .RE .TP \f[B]DC_LINE_LENGTH\f[R] If this environment variable exists and contains an integer that is greater than \f[B]1\f[R] and is less than \f[B]UINT16_MAX\f[R] (\f[B]2\[ha]16-1\f[R]), dc(1) will output lines to that length, including the backslash newline combo. The default line length is \f[B]70\f[R]. .RS .PP The special value of \f[B]0\f[R] will disable line length checking and print numbers without regard to line length and without backslashes and newlines. .RE .TP \f[B]DC_SIGINT_RESET\f[R] If dc(1) is not in interactive mode (see the \f[B]INTERACTIVE MODE\f[R] section), then this environment variable has no effect because dc(1) exits on \f[B]SIGINT\f[R] when not in interactive mode. .RS .PP However, when dc(1) is in interactive mode, then if this environment variable exists and contains an integer, a non-zero value makes dc(1) reset on \f[B]SIGINT\f[R], rather than exit, and zero makes dc(1) exit. If this environment variable exists and is \f[I]not\f[R] an integer, then dc(1) will exit on \f[B]SIGINT\f[R]. .PP This environment variable overrides the default, which can be queried with the \f[B]-h\f[R] or \f[B]--help\f[R] options. .RE .TP \f[B]DC_TTY_MODE\f[R] If TTY mode is \f[I]not\f[R] available (see the \f[B]TTY MODE\f[R] section), then this environment variable has no effect. .RS .PP However, when TTY mode is available, then if this environment variable exists and contains an integer, then a non-zero value makes dc(1) use TTY mode, and zero makes dc(1) not use TTY mode. .PP This environment variable overrides the default, which can be queried with the \f[B]-h\f[R] or \f[B]--help\f[R] options. .RE .TP \f[B]DC_PROMPT\f[R] If TTY mode is \f[I]not\f[R] available (see the \f[B]TTY MODE\f[R] section), then this environment variable has no effect. .RS .PP However, when TTY mode is available, then if this environment variable exists and contains an integer, a non-zero value makes dc(1) use a prompt, and zero or a non-integer makes dc(1) not use a prompt. If this environment variable does not exist and \f[B]DC_TTY_MODE\f[R] does, then the value of the \f[B]DC_TTY_MODE\f[R] environment variable is used. .PP This environment variable and the \f[B]DC_TTY_MODE\f[R] environment variable override the default, which can be queried with the \f[B]-h\f[R] or \f[B]--help\f[R] options. .RE +.TP +\f[B]DC_EXPR_EXIT\f[R] +If any expressions or expression files are given on the command-line +with \f[B]-e\f[R], \f[B]--expression\f[R], \f[B]-f\f[R], or +\f[B]--file\f[R], then if this environment variable exists and contains +an integer, a non-zero value makes dc(1) exit after executing the +expressions and expression files, and a non-zero value makes dc(1) not +exit. +.RS +.PP +This environment variable overrides the default, which can be queried +with the \f[B]-h\f[R] or \f[B]--help\f[R] options. +.RE .SH EXIT STATUS .PP dc(1) returns the following exit statuses: .TP \f[B]0\f[R] No error. .TP \f[B]1\f[R] A math error occurred. This follows standard practice of using \f[B]1\f[R] for expected errors, since math errors will happen in the process of normal execution. .RS .PP Math errors include divide by \f[B]0\f[R], taking the square root of a negative number, attempting to convert a negative number to a hardware integer, overflow when converting a number to a hardware integer, overflow when calculating the size of a number, and attempting to use a non-integer where an integer is required. .PP Converting to a hardware integer happens for the second operand of the power (\f[B]\[ha]\f[R]) operator. .RE .TP \f[B]2\f[R] A parse error occurred. .RS .PP Parse errors include unexpected \f[B]EOF\f[R], using an invalid character, failing to find the end of a string or comment, and using a token where it is invalid. .RE .TP \f[B]3\f[R] A runtime error occurred. .RS .PP Runtime errors include assigning an invalid number to any global (\f[B]ibase\f[R], \f[B]obase\f[R], or \f[B]scale\f[R]), giving a bad expression to a \f[B]read()\f[R] call, calling \f[B]read()\f[R] inside of a \f[B]read()\f[R] call, type errors (including attempting to execute a number), and attempting an operation when the stack has too few elements. .RE .TP \f[B]4\f[R] A fatal error occurred. .RS .PP Fatal errors include memory allocation errors, I/O errors, failing to open files, attempting to use files that do not have only ASCII characters (dc(1) only accepts ASCII characters), attempting to open a directory as a file, and giving invalid command-line options. .RE .PP The exit status \f[B]4\f[R] is special; when a fatal error occurs, dc(1) always exits and returns \f[B]4\f[R], no matter what mode dc(1) is in. .PP The other statuses will only be returned when dc(1) is not in interactive mode (see the \f[B]INTERACTIVE MODE\f[R] section), since dc(1) resets its state (see the \f[B]RESET\f[R] section) and accepts more input when one of those errors occurs in interactive mode. This is also the case when interactive mode is forced by the \f[B]-i\f[R] flag or \f[B]--interactive\f[R] option. .PP These exit statuses allow dc(1) to be used in shell scripting with error checking, and its normal behavior can be forced by using the \f[B]-i\f[R] flag or \f[B]--interactive\f[R] option. .SH INTERACTIVE MODE .PP Like bc(1), dc(1) has an interactive mode and a non-interactive mode. Interactive mode is turned on automatically when both \f[B]stdin\f[R] and \f[B]stdout\f[R] are hooked to a terminal, but the \f[B]-i\f[R] flag and \f[B]--interactive\f[R] option can turn it on in other situations. .PP In interactive mode, dc(1) attempts to recover from errors (see the \f[B]RESET\f[R] section), and in normal execution, flushes \f[B]stdout\f[R] as soon as execution is done for the current input. dc(1) may also reset on \f[B]SIGINT\f[R] instead of exit, depending on the contents of, or default for, the \f[B]DC_SIGINT_RESET\f[R] environment variable (see the \f[B]ENVIRONMENT VARIABLES\f[R] section). .SH TTY MODE .PP If \f[B]stdin\f[R], \f[B]stdout\f[R], and \f[B]stderr\f[R] are all connected to a TTY, then \[lq]TTY mode\[rq] is considered to be available, and thus, dc(1) can turn on TTY mode, subject to some settings. .PP If there is the environment variable \f[B]DC_TTY_MODE\f[R] in the environment (see the \f[B]ENVIRONMENT VARIABLES\f[R] section), then if that environment variable contains a non-zero integer, dc(1) will turn on TTY mode when \f[B]stdin\f[R], \f[B]stdout\f[R], and \f[B]stderr\f[R] are all connected to a TTY. If the \f[B]DC_TTY_MODE\f[R] environment variable exists but is \f[I]not\f[R] a non-zero integer, then dc(1) will not turn TTY mode on. .PP If the environment variable \f[B]DC_TTY_MODE\f[R] does \f[I]not\f[R] exist, the default setting is used. The default setting can be queried with the \f[B]-h\f[R] or \f[B]--help\f[R] options. .PP TTY mode is different from interactive mode because interactive mode is required in the bc(1) specification (https://pubs.opengroup.org/onlinepubs/9699919799/utilities/bc.html), and interactive mode requires only \f[B]stdin\f[R] and \f[B]stdout\f[R] to be connected to a terminal. .SS Command-Line History .PP Command-line history is only enabled if TTY mode is, i.e., that \f[B]stdin\f[R], \f[B]stdout\f[R], and \f[B]stderr\f[R] are connected to a TTY and the \f[B]DC_TTY_MODE\f[R] environment variable (see the \f[B]ENVIRONMENT VARIABLES\f[R] section) and its default do not disable TTY mode. See the \f[B]COMMAND LINE HISTORY\f[R] section for more information. .SS Prompt .PP If TTY mode is available, then a prompt can be enabled. Like TTY mode itself, it can be turned on or off with an environment variable: \f[B]DC_PROMPT\f[R] (see the \f[B]ENVIRONMENT VARIABLES\f[R] section). .PP If the environment variable \f[B]DC_PROMPT\f[R] exists and is a non-zero integer, then the prompt is turned on when \f[B]stdin\f[R], \f[B]stdout\f[R], and \f[B]stderr\f[R] are connected to a TTY and the \f[B]-P\f[R] and \f[B]--no-prompt\f[R] options were not used. The read prompt will be turned on under the same conditions, except that the \f[B]-R\f[R] and \f[B]--no-read-prompt\f[R] options must also not be used. .PP However, if \f[B]DC_PROMPT\f[R] does not exist, the prompt can be enabled or disabled with the \f[B]DC_TTY_MODE\f[R] environment variable, the \f[B]-P\f[R] and \f[B]--no-prompt\f[R] options, and the \f[B]-R\f[R] and \f[B]--no-read-prompt\f[R] options. See the \f[B]ENVIRONMENT VARIABLES\f[R] and \f[B]OPTIONS\f[R] sections for more details. .SH SIGNAL HANDLING .PP Sending a \f[B]SIGINT\f[R] will cause dc(1) to do one of two things. .PP If dc(1) is not in interactive mode (see the \f[B]INTERACTIVE MODE\f[R] section), or the \f[B]DC_SIGINT_RESET\f[R] environment variable (see the \f[B]ENVIRONMENT VARIABLES\f[R] section), or its default, is either not an integer or it is zero, dc(1) will exit. .PP However, if dc(1) is in interactive mode, and the \f[B]DC_SIGINT_RESET\f[R] or its default is an integer and non-zero, then dc(1) will stop executing the current input and reset (see the \f[B]RESET\f[R] section) upon receiving a \f[B]SIGINT\f[R]. .PP Note that \[lq]current input\[rq] can mean one of two things. If dc(1) is processing input from \f[B]stdin\f[R] in interactive mode, it will ask for more input. If dc(1) is processing input from a file in interactive mode, it will stop processing the file and start processing the next file, if one exists, or ask for input from \f[B]stdin\f[R] if no other file exists. .PP This means that if a \f[B]SIGINT\f[R] is sent to dc(1) as it is executing a file, it can seem as though dc(1) did not respond to the signal since it will immediately start executing the next file. This is by design; most files that users execute when interacting with dc(1) have function definitions, which are quick to parse. If a file takes a long time to execute, there may be a bug in that file. The rest of the files could still be executed without problem, allowing the user to continue. .PP \f[B]SIGTERM\f[R] and \f[B]SIGQUIT\f[R] cause dc(1) to clean up and exit, and it uses the default handler for all other signals. The one exception is \f[B]SIGHUP\f[R]; in that case, and only when dc(1) is in TTY mode (see the \f[B]TTY MODE\f[R] section), a \f[B]SIGHUP\f[R] will cause dc(1) to clean up and exit. .SH COMMAND LINE HISTORY .PP dc(1) supports interactive command-line editing. .PP If dc(1) can be in TTY mode (see the \f[B]TTY MODE\f[R] section), history can be enabled. This means that command-line history can only be enabled when \f[B]stdin\f[R], \f[B]stdout\f[R], and \f[B]stderr\f[R] are all connected to a TTY. .PP Like TTY mode itself, it can be turned on or off with the environment variable \f[B]DC_TTY_MODE\f[R] (see the \f[B]ENVIRONMENT VARIABLES\f[R] section). .PP \f[B]Note\f[R]: tabs are converted to 8 spaces. .SH LOCALES .PP This dc(1) ships with support for adding error messages for different locales and thus, supports \f[B]LC_MESSAGES\f[R]. .SH SEE ALSO .PP bc(1) .SH STANDARDS .PP The dc(1) utility operators are compliant with the operators in the bc(1) IEEE Std 1003.1-2017 (\[lq]POSIX.1-2017\[rq]) (https://pubs.opengroup.org/onlinepubs/9699919799/utilities/bc.html) specification. .SH BUGS .PP None are known. Report bugs at https://git.yzena.com/gavin/bc. .SH AUTHOR .PP Gavin D. Howard and contributors. diff --git a/contrib/bc/manuals/dc/E.1.md b/contrib/bc/manuals/dc/E.1.md index 6a2c465e5642..a138fdb32158 100644 --- a/contrib/bc/manuals/dc/E.1.md +++ b/contrib/bc/manuals/dc/E.1.md @@ -1,1217 +1,1228 @@ # Name dc - arbitrary-precision decimal reverse-Polish notation calculator # SYNOPSIS **dc** [**-hiPRvVx**] [**-\-version**] [**-\-help**] [**-\-interactive**] [**-\-no-prompt**] [**-\-no-read-prompt**] [**-\-extended-register**] [**-e** *expr*] [**-\-expression**=*expr*...] [**-f** *file*...] [**-\-file**=*file*...] [*file*...] # DESCRIPTION dc(1) is an arbitrary-precision calculator. It uses a stack (reverse Polish notation) to store numbers and results of computations. Arithmetic operations pop arguments off of the stack and push the results. If no files are given on the command-line, then dc(1) reads from **stdin** (see the **STDIN** section). Otherwise, those files are processed, and dc(1) will then exit. If a user wants to set up a standard environment, they can use **DC_ENV_ARGS** (see the **ENVIRONMENT VARIABLES** section). For example, if a user wants the **scale** always set to **10**, they can set **DC_ENV_ARGS** to **-e 10k**, and this dc(1) will always start with a **scale** of **10**. # OPTIONS The following are the options that dc(1) accepts. **-h**, **-\-help** : Prints a usage message and quits. **-v**, **-V**, **-\-version** : Print the version information (copyright header) and exit. **-i**, **-\-interactive** : Forces interactive mode. (See the **INTERACTIVE MODE** section.) This is a **non-portable extension**. **-L**, **-\-no-line-length** : Disables line length checking and prints numbers without backslashes and newlines. In other words, this option sets **BC_LINE_LENGTH** to **0** (see the **ENVIRONMENT VARIABLES** section). This is a **non-portable extension**. **-P**, **-\-no-prompt** : Disables the prompt in TTY mode. (The prompt is only enabled in TTY mode. See the **TTY MODE** section.) This is mostly for those users that do not want a prompt or are not used to having them in dc(1). Most of those users would want to put this option in **DC_ENV_ARGS**. These options override the **DC_PROMPT** and **DC_TTY_MODE** environment variables (see the **ENVIRONMENT VARIABLES** section). This is a **non-portable extension**. **-R**, **-\-no-read-prompt** : Disables the read prompt in TTY mode. (The read prompt is only enabled in TTY mode. See the **TTY MODE** section.) This is mostly for those users that do not want a read prompt or are not used to having them in dc(1). Most of those users would want to put this option in **BC_ENV_ARGS** (see the **ENVIRONMENT VARIABLES** section). This option is also useful in hash bang lines of dc(1) scripts that prompt for user input. This option does not disable the regular prompt because the read prompt is only used when the **?** command is used. These options *do* override the **DC_PROMPT** and **DC_TTY_MODE** environment variables (see the **ENVIRONMENT VARIABLES** section), but only for the read prompt. This is a **non-portable extension**. **-x** **-\-extended-register** : Enables extended register mode. See the *Extended Register Mode* subsection of the **REGISTERS** section for more information. This is a **non-portable extension**. **-z**, **-\-leading-zeroes** : Makes bc(1) print all numbers greater than **-1** and less than **1**, and not equal to **0**, with a leading zero. This can be set for individual numbers with the **plz(x)**, plznl(x)**, **pnlz(x)**, and **pnlznl(x)** functions in the extended math library (see the **LIBRARY** section). This is a **non-portable extension**. **-e** *expr*, **-\-expression**=*expr* : Evaluates *expr*. If multiple expressions are given, they are evaluated in order. If files are given as well (see below), the expressions and files are evaluated in the order given. This means that if a file is given before an expression, the file is read in and evaluated first. If this option is given on the command-line (i.e., not in **DC_ENV_ARGS**, see the **ENVIRONMENT VARIABLES** section), then after processing all expressions and files, dc(1) will exit, unless **-** (**stdin**) was given as an argument at least once to **-f** or **-\-file**, whether on the command-line or in **DC_ENV_ARGS**. However, if any other **-e**, **-\-expression**, **-f**, or **-\-file** arguments are given after **-f-** or equivalent is given, dc(1) will give a fatal error and exit. This is a **non-portable extension**. **-f** *file*, **-\-file**=*file* : Reads in *file* and evaluates it, line by line, as though it were read through **stdin**. If expressions are also given (see above), the expressions are evaluated in the order given. If this option is given on the command-line (i.e., not in **DC_ENV_ARGS**, see the **ENVIRONMENT VARIABLES** section), then after processing all expressions and files, dc(1) will exit, unless **-** (**stdin**) was given as an argument at least once to **-f** or **-\-file**. However, if any other **-e**, **-\-expression**, **-f**, or **-\-file** arguments are given after **-f-** or equivalent is given, dc(1) will give a fatal error and exit. This is a **non-portable extension**. All long options are **non-portable extensions**. # STDIN If no files are given on the command-line and no files or expressions are given by the **-f**, **-\-file**, **-e**, or **-\-expression** options, then dc(1) read from **stdin**. However, there is a caveat to this. First, **stdin** is evaluated a line at a time. The only exception to this is if a string has been finished, but not ended. This means that, except for escaped brackets, all brackets must be balanced before dc(1) parses and executes. # STDOUT Any non-error output is written to **stdout**. In addition, if history (see the **HISTORY** section) and the prompt (see the **TTY MODE** section) are enabled, both are output to **stdout**. **Note**: Unlike other dc(1) implementations, this dc(1) will issue a fatal error (see the **EXIT STATUS** section) if it cannot write to **stdout**, so if **stdout** is closed, as in **dc >&-**, it will quit with an error. This is done so that dc(1) can report problems when **stdout** is redirected to a file. If there are scripts that depend on the behavior of other dc(1) implementations, it is recommended that those scripts be changed to redirect **stdout** to **/dev/null**. # STDERR Any error output is written to **stderr**. **Note**: Unlike other dc(1) implementations, this dc(1) will issue a fatal error (see the **EXIT STATUS** section) if it cannot write to **stderr**, so if **stderr** is closed, as in **dc 2>&-**, it will quit with an error. This is done so that dc(1) can exit with an error code when **stderr** is redirected to a file. If there are scripts that depend on the behavior of other dc(1) implementations, it is recommended that those scripts be changed to redirect **stderr** to **/dev/null**. # SYNTAX Each item in the input source code, either a number (see the **NUMBERS** section) or a command (see the **COMMANDS** section), is processed and executed, in order. Input is processed immediately when entered. **ibase** is a register (see the **REGISTERS** section) that determines how to interpret constant numbers. It is the "input" base, or the number base used for interpreting input numbers. **ibase** is initially **10**. The max allowable value for **ibase** is **16**. The min allowable value for **ibase** is **2**. The max allowable value for **ibase** can be queried in dc(1) programs with the **T** command. **obase** is a register (see the **REGISTERS** section) that determines how to output results. It is the "output" base, or the number base used for outputting numbers. **obase** is initially **10**. The max allowable value for **obase** is **DC_BASE_MAX** and can be queried with the **U** command. The min allowable value for **obase** is **2**. Values are output in the specified base. The *scale* of an expression is the number of digits in the result of the expression right of the decimal point, and **scale** is a register (see the **REGISTERS** section) that sets the precision of any operations (with exceptions). **scale** is initially **0**. **scale** cannot be negative. The max allowable value for **scale** can be queried in dc(1) programs with the **V** command. ## Comments Comments go from **#** until, and not including, the next newline. This is a **non-portable extension**. # NUMBERS Numbers are strings made up of digits, uppercase letters up to **F**, and at most **1** period for a radix. Numbers can have up to **DC_NUM_MAX** digits. Uppercase letters are equal to **9** + their position in the alphabet (i.e., **A** equals **10**, or **9+1**). If a digit or letter makes no sense with the current value of **ibase**, they are set to the value of the highest valid digit in **ibase**. Single-character numbers (i.e., **A** alone) take the value that they would have if they were valid digits, regardless of the value of **ibase**. This means that **A** alone always equals decimal **10** and **F** alone always equals decimal **15**. # COMMANDS The valid commands are listed below. ## Printing These commands are used for printing. **p** : Prints the value on top of the stack, whether number or string, and prints a newline after. This does not alter the stack. **n** : Prints the value on top of the stack, whether number or string, and pops it off of the stack. **P** : Pops a value off the stack. If the value is a number, it is truncated and the absolute value of the result is printed as though **obase** is **256** and each digit is interpreted as an 8-bit ASCII character, making it a byte stream. If the value is a string, it is printed without a trailing newline. This is a **non-portable extension**. **f** : Prints the entire contents of the stack, in order from newest to oldest, without altering anything. Users should use this command when they get lost. ## Arithmetic These are the commands used for arithmetic. **+** : The top two values are popped off the stack, added, and the result is pushed onto the stack. The *scale* of the result is equal to the max *scale* of both operands. **-** : The top two values are popped off the stack, subtracted, and the result is pushed onto the stack. The *scale* of the result is equal to the max *scale* of both operands. **\*** : The top two values are popped off the stack, multiplied, and the result is pushed onto the stack. If **a** is the *scale* of the first expression and **b** is the *scale* of the second expression, the *scale* of the result is equal to **min(a+b,max(scale,a,b))** where **min()** and **max()** return the obvious values. **/** : The top two values are popped off the stack, divided, and the result is pushed onto the stack. The *scale* of the result is equal to **scale**. The first value popped off of the stack must be non-zero. **%** : The top two values are popped off the stack, remaindered, and the result is pushed onto the stack. Remaindering is equivalent to 1) Computing **a/b** to current **scale**, and 2) Using the result of step 1 to calculate **a-(a/b)\*b** to *scale* **max(scale+scale(b),scale(a))**. The first value popped off of the stack must be non-zero. **~** : The top two values are popped off the stack, divided and remaindered, and the results (divided first, remainder second) are pushed onto the stack. This is equivalent to **x y / x y %** except that **x** and **y** are only evaluated once. The first value popped off of the stack must be non-zero. This is a **non-portable extension**. **\^** : The top two values are popped off the stack, the second is raised to the power of the first, and the result is pushed onto the stack. The *scale* of the result is equal to **scale**. The first value popped off of the stack must be an integer, and if that value is negative, the second value popped off of the stack must be non-zero. **v** : The top value is popped off the stack, its square root is computed, and the result is pushed onto the stack. The *scale* of the result is equal to **scale**. The value popped off of the stack must be non-negative. **\_** : If this command *immediately* precedes a number (i.e., no spaces or other commands), then that number is input as a negative number. Otherwise, the top value on the stack is popped and copied, and the copy is negated and pushed onto the stack. This behavior without a number is a **non-portable extension**. **b** : The top value is popped off the stack, and if it is zero, it is pushed back onto the stack. Otherwise, its absolute value is pushed onto the stack. This is a **non-portable extension**. **|** : The top three values are popped off the stack, a modular exponentiation is computed, and the result is pushed onto the stack. The first value popped is used as the reduction modulus and must be an integer and non-zero. The second value popped is used as the exponent and must be an integer and non-negative. The third value popped is the base and must be an integer. This is a **non-portable extension**. **G** : The top two values are popped off of the stack, they are compared, and a **1** is pushed if they are equal, or **0** otherwise. This is a **non-portable extension**. **N** : The top value is popped off of the stack, and if it a **0**, a **1** is pushed; otherwise, a **0** is pushed. This is a **non-portable extension**. **(** : The top two values are popped off of the stack, they are compared, and a **1** is pushed if the first is less than the second, or **0** otherwise. This is a **non-portable extension**. **{** : The top two values are popped off of the stack, they are compared, and a **1** is pushed if the first is less than or equal to the second, or **0** otherwise. This is a **non-portable extension**. **)** : The top two values are popped off of the stack, they are compared, and a **1** is pushed if the first is greater than the second, or **0** otherwise. This is a **non-portable extension**. **}** : The top two values are popped off of the stack, they are compared, and a **1** is pushed if the first is greater than or equal to the second, or **0** otherwise. This is a **non-portable extension**. **M** : The top two values are popped off of the stack. If they are both non-zero, a **1** is pushed onto the stack. If either of them is zero, or both of them are, then a **0** is pushed onto the stack. This is like the **&&** operator in bc(1), and it is *not* a short-circuit operator. This is a **non-portable extension**. **m** : The top two values are popped off of the stack. If at least one of them is non-zero, a **1** is pushed onto the stack. If both of them are zero, then a **0** is pushed onto the stack. This is like the **||** operator in bc(1), and it is *not* a short-circuit operator. This is a **non-portable extension**. ## Stack Control These commands control the stack. **c** : Removes all items from ("clears") the stack. **d** : Copies the item on top of the stack ("duplicates") and pushes the copy onto the stack. **r** : Swaps ("reverses") the two top items on the stack. **R** : Pops ("removes") the top value from the stack. ## Register Control These commands control registers (see the **REGISTERS** section). **s**_r_ : Pops the value off the top of the stack and stores it into register *r*. **l**_r_ : Copies the value in register *r* and pushes it onto the stack. This does not alter the contents of *r*. **S**_r_ : Pops the value off the top of the (main) stack and pushes it onto the stack of register *r*. The previous value of the register becomes inaccessible. **L**_r_ : Pops the value off the top of the stack for register *r* and push it onto the main stack. The previous value in the stack for register *r*, if any, is now accessible via the **l**_r_ command. ## Parameters These commands control the values of **ibase**, **obase**, and **scale**. Also see the **SYNTAX** section. **i** : Pops the value off of the top of the stack and uses it to set **ibase**, which must be between **2** and **16**, inclusive. If the value on top of the stack has any *scale*, the *scale* is ignored. **o** : Pops the value off of the top of the stack and uses it to set **obase**, which must be between **2** and **DC_BASE_MAX**, inclusive (see the **LIMITS** section). If the value on top of the stack has any *scale*, the *scale* is ignored. **k** : Pops the value off of the top of the stack and uses it to set **scale**, which must be non-negative. If the value on top of the stack has any *scale*, the *scale* is ignored. **I** : Pushes the current value of **ibase** onto the main stack. **O** : Pushes the current value of **obase** onto the main stack. **K** : Pushes the current value of **scale** onto the main stack. **T** : Pushes the maximum allowable value of **ibase** onto the main stack. This is a **non-portable extension**. **U** : Pushes the maximum allowable value of **obase** onto the main stack. This is a **non-portable extension**. **V** : Pushes the maximum allowable value of **scale** onto the main stack. This is a **non-portable extension**. ## Strings The following commands control strings. dc(1) can work with both numbers and strings, and registers (see the **REGISTERS** section) can hold both strings and numbers. dc(1) always knows whether the contents of a register are a string or a number. While arithmetic operations have to have numbers, and will print an error if given a string, other commands accept strings. Strings can also be executed as macros. For example, if the string **[1pR]** is executed as a macro, then the code **1pR** is executed, meaning that the **1** will be printed with a newline after and then popped from the stack. **\[**_characters_**\]** : Makes a string containing *characters* and pushes it onto the stack. If there are brackets (**\[** and **\]**) in the string, then they must be balanced. Unbalanced brackets can be escaped using a backslash (**\\**) character. If there is a backslash character in the string, the character after it (even another backslash) is put into the string verbatim, but the (first) backslash is not. **a** : The value on top of the stack is popped. If it is a number, it is truncated and its absolute value is taken. The result mod **256** is calculated. If that result is **0**, push an empty string; otherwise, push a one-character string where the character is the result of the mod interpreted as an ASCII character. If it is a string, then a new string is made. If the original string is empty, the new string is empty. If it is not, then the first character of the original string is used to create the new string as a one-character string. The new string is then pushed onto the stack. This is a **non-portable extension**. **x** : Pops a value off of the top of the stack. If it is a number, it is pushed back onto the stack. If it is a string, it is executed as a macro. This behavior is the norm whenever a macro is executed, whether by this command or by the conditional execution commands below. **\>**_r_ : Pops two values off of the stack that must be numbers and compares them. If the first value is greater than the second, then the contents of register *r* are executed. For example, **0 1>a** will execute the contents of register **a**, and **1 0>a** will not. If either or both of the values are not numbers, dc(1) will raise an error and reset (see the **RESET** section). **>**_r_**e**_s_ : Like the above, but will execute register *s* if the comparison fails. If either or both of the values are not numbers, dc(1) will raise an error and reset (see the **RESET** section). This is a **non-portable extension**. **!\>**_r_ : Pops two values off of the stack that must be numbers and compares them. If the first value is not greater than the second (less than or equal to), then the contents of register *r* are executed. If either or both of the values are not numbers, dc(1) will raise an error and reset (see the **RESET** section). **!\>**_r_**e**_s_ : Like the above, but will execute register *s* if the comparison fails. If either or both of the values are not numbers, dc(1) will raise an error and reset (see the **RESET** section). This is a **non-portable extension**. **\<**_r_ : Pops two values off of the stack that must be numbers and compares them. If the first value is less than the second, then the contents of register *r* are executed. If either or both of the values are not numbers, dc(1) will raise an error and reset (see the **RESET** section). **\<**_r_**e**_s_ : Like the above, but will execute register *s* if the comparison fails. If either or both of the values are not numbers, dc(1) will raise an error and reset (see the **RESET** section). This is a **non-portable extension**. **!\<**_r_ : Pops two values off of the stack that must be numbers and compares them. If the first value is not less than the second (greater than or equal to), then the contents of register *r* are executed. If either or both of the values are not numbers, dc(1) will raise an error and reset (see the **RESET** section). **!\<**_r_**e**_s_ : Like the above, but will execute register *s* if the comparison fails. If either or both of the values are not numbers, dc(1) will raise an error and reset (see the **RESET** section). This is a **non-portable extension**. **=**_r_ : Pops two values off of the stack that must be numbers and compares them. If the first value is equal to the second, then the contents of register *r* are executed. If either or both of the values are not numbers, dc(1) will raise an error and reset (see the **RESET** section). **=**_r_**e**_s_ : Like the above, but will execute register *s* if the comparison fails. If either or both of the values are not numbers, dc(1) will raise an error and reset (see the **RESET** section). This is a **non-portable extension**. **!=**_r_ : Pops two values off of the stack that must be numbers and compares them. If the first value is not equal to the second, then the contents of register *r* are executed. If either or both of the values are not numbers, dc(1) will raise an error and reset (see the **RESET** section). **!=**_r_**e**_s_ : Like the above, but will execute register *s* if the comparison fails. If either or both of the values are not numbers, dc(1) will raise an error and reset (see the **RESET** section). This is a **non-portable extension**. **?** : Reads a line from the **stdin** and executes it. This is to allow macros to request input from users. **q** : During execution of a macro, this exits the execution of that macro and the execution of the macro that executed it. If there are no macros, or only one macro executing, dc(1) exits. **Q** : Pops a value from the stack which must be non-negative and is used the number of macro executions to pop off of the execution stack. If the number of levels to pop is greater than the number of executing macros, dc(1) exits. **,** : Pushes the depth of the execution stack onto the stack. The execution stack is the stack of string executions. The number that is pushed onto the stack is exactly as many as is needed to make dc(1) exit with the **Q** command, so the sequence **,Q** will make dc(1) exit. ## Status These commands query status of the stack or its top value. **Z** : Pops a value off of the stack. If it is a number, calculates the number of significant decimal digits it has and pushes the result. It will push **1** if the argument is **0** with no decimal places. If it is a string, pushes the number of characters the string has. **X** : Pops a value off of the stack. If it is a number, pushes the *scale* of the value onto the stack. If it is a string, pushes **0**. **z** : Pushes the current depth of the stack (before execution of this command) onto the stack. **y**_r_ : Pushes the current stack depth of the register *r* onto the main stack. Because each register has a depth of **1** (with the value **0** in the top item) when dc(1) starts, dc(1) requires that each register's stack must always have at least one item; dc(1) will give an error and reset otherwise (see the **RESET** section). This means that this command will never push **0**. This is a **non-portable extension**. ## Arrays These commands manipulate arrays. **:**_r_ : Pops the top two values off of the stack. The second value will be stored in the array *r* (see the **REGISTERS** section), indexed by the first value. **;**_r_ : Pops the value on top of the stack and uses it as an index into the array *r*. The selected value is then pushed onto the stack. **Y**_r_ : Pushes the length of the array *r* onto the stack. This is a **non-portable extension**. ## Global Settings These commands retrieve global settings. These are the only commands that require multiple specific characters, and all of them begin with the letter **g**. Only the characters below are allowed after the character **g**; any other character produces a parse error (see the **ERRORS** section). **gl** : Pushes the line length set by **DC_LINE_LENGTH** (see the **ENVIRONMENT VARIABLES** section) onto the stack. **gz** : Pushes **0** onto the stack if the leading zero setting has not been enabled with the **-z** or **-\-leading-zeroes** options (see the **OPTIONS** section), non-zero otherwise. # REGISTERS Registers are names that can store strings, numbers, and arrays. (Number/string registers do not interfere with array registers.) Each register is also its own stack, so the current register value is the top of the stack for the register. All registers, when first referenced, have one value (**0**) in their stack, and it is a runtime error to attempt to pop that item off of the register stack. In non-extended register mode, a register name is just the single character that follows any command that needs a register name. The only exceptions are: a newline (**'\\n'**) and a left bracket (**'['**); it is a parse error for a newline or a left bracket to be used as a register name. ## Extended Register Mode Unlike most other dc(1) implentations, this dc(1) provides nearly unlimited amounts of registers, if extended register mode is enabled. If extended register mode is enabled (**-x** or **-\-extended-register** command-line arguments are given), then normal single character registers are used *unless* the character immediately following a command that needs a register name is a space (according to **isspace()**) and not a newline (**'\\n'**). In that case, the register name is found according to the regex **\[a-z\]\[a-z0-9\_\]\*** (like bc(1) identifiers), and it is a parse error if the next non-space characters do not match that regex. # RESET When dc(1) encounters an error or a signal that it has a non-default handler for, it resets. This means that several things happen. First, any macros that are executing are stopped and popped off the stack. The behavior is not unlike that of exceptions in programming languages. Then the execution point is set so that any code waiting to execute (after all macros returned) is skipped. Thus, when dc(1) resets, it skips any remaining code waiting to be executed. Then, if it is interactive mode, and the error was not a fatal error (see the **EXIT STATUS** section), it asks for more input; otherwise, it exits with the appropriate return code. # PERFORMANCE Most dc(1) implementations use **char** types to calculate the value of **1** decimal digit at a time, but that can be slow. This dc(1) does something different. It uses large integers to calculate more than **1** decimal digit at a time. If built in a environment where **DC_LONG_BIT** (see the **LIMITS** section) is **64**, then each integer has **9** decimal digits. If built in an environment where **DC_LONG_BIT** is **32** then each integer has **4** decimal digits. This value (the number of decimal digits per large integer) is called **DC_BASE_DIGS**. In addition, this dc(1) uses an even larger integer for overflow checking. This integer type depends on the value of **DC_LONG_BIT**, but is always at least twice as large as the integer type used to store digits. # LIMITS The following are the limits on dc(1): **DC_LONG_BIT** : The number of bits in the **long** type in the environment where dc(1) was built. This determines how many decimal digits can be stored in a single large integer (see the **PERFORMANCE** section). **DC_BASE_DIGS** : The number of decimal digits per large integer (see the **PERFORMANCE** section). Depends on **DC_LONG_BIT**. **DC_BASE_POW** : The max decimal number that each large integer can store (see **DC_BASE_DIGS**) plus **1**. Depends on **DC_BASE_DIGS**. **DC_OVERFLOW_MAX** : The max number that the overflow type (see the **PERFORMANCE** section) can hold. Depends on **DC_LONG_BIT**. **DC_BASE_MAX** : The maximum output base. Set at **DC_BASE_POW**. **DC_DIM_MAX** : The maximum size of arrays. Set at **SIZE_MAX-1**. **DC_SCALE_MAX** : The maximum **scale**. Set at **DC_OVERFLOW_MAX-1**. **DC_STRING_MAX** : The maximum length of strings. Set at **DC_OVERFLOW_MAX-1**. **DC_NAME_MAX** : The maximum length of identifiers. Set at **DC_OVERFLOW_MAX-1**. **DC_NUM_MAX** : The maximum length of a number (in decimal digits), which includes digits after the decimal point. Set at **DC_OVERFLOW_MAX-1**. Exponent : The maximum allowable exponent (positive or negative). Set at **DC_OVERFLOW_MAX**. Number of vars : The maximum number of vars/arrays. Set at **SIZE_MAX-1**. These limits are meant to be effectively non-existent; the limits are so large (at least on 64-bit machines) that there should not be any point at which they become a problem. In fact, memory should be exhausted before these limits should be hit. # ENVIRONMENT VARIABLES dc(1) recognizes the following environment variables: **DC_ENV_ARGS** : This is another way to give command-line arguments to dc(1). They should be in the same format as all other command-line arguments. These are always processed first, so any files given in **DC_ENV_ARGS** will be processed before arguments and files given on the command-line. This gives the user the ability to set up "standard" options and files to be used at every invocation. The most useful thing for such files to contain would be useful functions that the user might want every time dc(1) runs. Another use would be to use the **-e** option to set **scale** to a value other than **0**. The code that parses **DC_ENV_ARGS** will correctly handle quoted arguments, but it does not understand escape sequences. For example, the string **"/home/gavin/some dc file.dc"** will be correctly parsed, but the string **"/home/gavin/some \"dc\" file.dc"** will include the backslashes. The quote parsing will handle either kind of quotes, **'** or **"**. Thus, if you have a file with any number of single quotes in the name, you can use double quotes as the outside quotes, as in **"some 'dc' file.dc"**, and vice versa if you have a file with double quotes. However, handling a file with both kinds of quotes in **DC_ENV_ARGS** is not supported due to the complexity of the parsing, though such files are still supported on the command-line where the parsing is done by the shell. **DC_LINE_LENGTH** : If this environment variable exists and contains an integer that is greater than **1** and is less than **UINT16_MAX** (**2\^16-1**), dc(1) will output lines to that length, including the backslash newline combo. The default line length is **70**. The special value of **0** will disable line length checking and print numbers without regard to line length and without backslashes and newlines. **DC_SIGINT_RESET** : If dc(1) is not in interactive mode (see the **INTERACTIVE MODE** section), then this environment variable has no effect because dc(1) exits on **SIGINT** when not in interactive mode. However, when dc(1) is in interactive mode, then if this environment variable exists and contains an integer, a non-zero value makes dc(1) reset on **SIGINT**, rather than exit, and zero makes dc(1) exit. If this environment variable exists and is *not* an integer, then dc(1) will exit on **SIGINT**. This environment variable overrides the default, which can be queried with the **-h** or **-\-help** options. **DC_TTY_MODE** : If TTY mode is *not* available (see the **TTY MODE** section), then this environment variable has no effect. However, when TTY mode is available, then if this environment variable exists and contains an integer, then a non-zero value makes dc(1) use TTY mode, and zero makes dc(1) not use TTY mode. This environment variable overrides the default, which can be queried with the **-h** or **-\-help** options. **DC_PROMPT** : If TTY mode is *not* available (see the **TTY MODE** section), then this environment variable has no effect. However, when TTY mode is available, then if this environment variable exists and contains an integer, a non-zero value makes dc(1) use a prompt, and zero or a non-integer makes dc(1) not use a prompt. If this environment variable does not exist and **DC_TTY_MODE** does, then the value of the **DC_TTY_MODE** environment variable is used. This environment variable and the **DC_TTY_MODE** environment variable override the default, which can be queried with the **-h** or **-\-help** options. +**DC_EXPR_EXIT** + +: If any expressions or expression files are given on the command-line with + **-e**, **-\-expression**, **-f**, or **-\-file**, then if this environment + variable exists and contains an integer, a non-zero value makes dc(1) exit + after executing the expressions and expression files, and a non-zero value + makes dc(1) not exit. + + This environment variable overrides the default, which can be queried with + the **-h** or **-\-help** options. + # EXIT STATUS dc(1) returns the following exit statuses: **0** : No error. **1** : A math error occurred. This follows standard practice of using **1** for expected errors, since math errors will happen in the process of normal execution. Math errors include divide by **0**, taking the square root of a negative number, attempting to convert a negative number to a hardware integer, overflow when converting a number to a hardware integer, overflow when calculating the size of a number, and attempting to use a non-integer where an integer is required. Converting to a hardware integer happens for the second operand of the power (**\^**) operator. **2** : A parse error occurred. Parse errors include unexpected **EOF**, using an invalid character, failing to find the end of a string or comment, and using a token where it is invalid. **3** : A runtime error occurred. Runtime errors include assigning an invalid number to any global (**ibase**, **obase**, or **scale**), giving a bad expression to a **read()** call, calling **read()** inside of a **read()** call, type errors (including attempting to execute a number), and attempting an operation when the stack has too few elements. **4** : A fatal error occurred. Fatal errors include memory allocation errors, I/O errors, failing to open files, attempting to use files that do not have only ASCII characters (dc(1) only accepts ASCII characters), attempting to open a directory as a file, and giving invalid command-line options. The exit status **4** is special; when a fatal error occurs, dc(1) always exits and returns **4**, no matter what mode dc(1) is in. The other statuses will only be returned when dc(1) is not in interactive mode (see the **INTERACTIVE MODE** section), since dc(1) resets its state (see the **RESET** section) and accepts more input when one of those errors occurs in interactive mode. This is also the case when interactive mode is forced by the **-i** flag or **-\-interactive** option. These exit statuses allow dc(1) to be used in shell scripting with error checking, and its normal behavior can be forced by using the **-i** flag or **-\-interactive** option. # INTERACTIVE MODE Like bc(1), dc(1) has an interactive mode and a non-interactive mode. Interactive mode is turned on automatically when both **stdin** and **stdout** are hooked to a terminal, but the **-i** flag and **-\-interactive** option can turn it on in other situations. In interactive mode, dc(1) attempts to recover from errors (see the **RESET** section), and in normal execution, flushes **stdout** as soon as execution is done for the current input. dc(1) may also reset on **SIGINT** instead of exit, depending on the contents of, or default for, the **DC_SIGINT_RESET** environment variable (see the **ENVIRONMENT VARIABLES** section). # TTY MODE If **stdin**, **stdout**, and **stderr** are all connected to a TTY, then "TTY mode" is considered to be available, and thus, dc(1) can turn on TTY mode, subject to some settings. If there is the environment variable **DC_TTY_MODE** in the environment (see the **ENVIRONMENT VARIABLES** section), then if that environment variable contains a non-zero integer, dc(1) will turn on TTY mode when **stdin**, **stdout**, and **stderr** are all connected to a TTY. If the **DC_TTY_MODE** environment variable exists but is *not* a non-zero integer, then dc(1) will not turn TTY mode on. If the environment variable **DC_TTY_MODE** does *not* exist, the default setting is used. The default setting can be queried with the **-h** or **-\-help** options. TTY mode is different from interactive mode because interactive mode is required in the [bc(1) specification][1], and interactive mode requires only **stdin** and **stdout** to be connected to a terminal. ## Command-Line History Command-line history is only enabled if TTY mode is, i.e., that **stdin**, **stdout**, and **stderr** are connected to a TTY and the **DC_TTY_MODE** environment variable (see the **ENVIRONMENT VARIABLES** section) and its default do not disable TTY mode. See the **COMMAND LINE HISTORY** section for more information. ## Prompt If TTY mode is available, then a prompt can be enabled. Like TTY mode itself, it can be turned on or off with an environment variable: **DC_PROMPT** (see the **ENVIRONMENT VARIABLES** section). If the environment variable **DC_PROMPT** exists and is a non-zero integer, then the prompt is turned on when **stdin**, **stdout**, and **stderr** are connected to a TTY and the **-P** and **-\-no-prompt** options were not used. The read prompt will be turned on under the same conditions, except that the **-R** and **-\-no-read-prompt** options must also not be used. However, if **DC_PROMPT** does not exist, the prompt can be enabled or disabled with the **DC_TTY_MODE** environment variable, the **-P** and **-\-no-prompt** options, and the **-R** and **-\-no-read-prompt** options. See the **ENVIRONMENT VARIABLES** and **OPTIONS** sections for more details. # SIGNAL HANDLING Sending a **SIGINT** will cause dc(1) to do one of two things. If dc(1) is not in interactive mode (see the **INTERACTIVE MODE** section), or the **DC_SIGINT_RESET** environment variable (see the **ENVIRONMENT VARIABLES** section), or its default, is either not an integer or it is zero, dc(1) will exit. However, if dc(1) is in interactive mode, and the **DC_SIGINT_RESET** or its default is an integer and non-zero, then dc(1) will stop executing the current input and reset (see the **RESET** section) upon receiving a **SIGINT**. Note that "current input" can mean one of two things. If dc(1) is processing input from **stdin** in interactive mode, it will ask for more input. If dc(1) is processing input from a file in interactive mode, it will stop processing the file and start processing the next file, if one exists, or ask for input from **stdin** if no other file exists. This means that if a **SIGINT** is sent to dc(1) as it is executing a file, it can seem as though dc(1) did not respond to the signal since it will immediately start executing the next file. This is by design; most files that users execute when interacting with dc(1) have function definitions, which are quick to parse. If a file takes a long time to execute, there may be a bug in that file. The rest of the files could still be executed without problem, allowing the user to continue. **SIGTERM** and **SIGQUIT** cause dc(1) to clean up and exit, and it uses the default handler for all other signals. The one exception is **SIGHUP**; in that case, and only when dc(1) is in TTY mode (see the **TTY MODE** section), a **SIGHUP** will cause dc(1) to clean up and exit. # COMMAND LINE HISTORY dc(1) supports interactive command-line editing. If dc(1) can be in TTY mode (see the **TTY MODE** section), history can be enabled. This means that command-line history can only be enabled when **stdin**, **stdout**, and **stderr** are all connected to a TTY. Like TTY mode itself, it can be turned on or off with the environment variable **DC_TTY_MODE** (see the **ENVIRONMENT VARIABLES** section). **Note**: tabs are converted to 8 spaces. # LOCALES This dc(1) ships with support for adding error messages for different locales and thus, supports **LC_MESSAGES**. # SEE ALSO bc(1) # STANDARDS The dc(1) utility operators are compliant with the operators in the bc(1) [IEEE Std 1003.1-2017 (“POSIX.1-2017”)][1] specification. # BUGS None are known. Report bugs at https://git.yzena.com/gavin/bc. # AUTHOR Gavin D. Howard and contributors. [1]: https://pubs.opengroup.org/onlinepubs/9699919799/utilities/bc.html diff --git a/contrib/bc/manuals/dc/EH.1 b/contrib/bc/manuals/dc/EH.1 index 4506001dfe55..97c05ca44094 100644 --- a/contrib/bc/manuals/dc/EH.1 +++ b/contrib/bc/manuals/dc/EH.1 @@ -1,1316 +1,1329 @@ .\" .\" SPDX-License-Identifier: BSD-2-Clause .\" .\" Copyright (c) 2018-2021 Gavin D. Howard and contributors. .\" .\" Redistribution and use in source and binary forms, with or without .\" modification, are permitted provided that the following conditions are met: .\" .\" * Redistributions of source code must retain the above copyright notice, .\" this list of conditions and the following disclaimer. .\" .\" * Redistributions in binary form must reproduce the above copyright notice, .\" this list of conditions and the following disclaimer in the documentation .\" and/or other materials provided with the distribution. .\" .\" THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" .\" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE .\" IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE .\" ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE .\" LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR .\" CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF .\" SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS .\" INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN .\" CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) .\" ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE .\" POSSIBILITY OF SUCH DAMAGE. .\" .TH "DC" "1" "June 2021" "Gavin D. Howard" "General Commands Manual" .SH Name .PP dc - arbitrary-precision decimal reverse-Polish notation calculator .SH SYNOPSIS .PP \f[B]dc\f[R] [\f[B]-hiPRvVx\f[R]] [\f[B]--version\f[R]] [\f[B]--help\f[R]] [\f[B]--interactive\f[R]] [\f[B]--no-prompt\f[R]] [\f[B]--no-read-prompt\f[R]] [\f[B]--extended-register\f[R]] [\f[B]-e\f[R] \f[I]expr\f[R]] [\f[B]--expression\f[R]=\f[I]expr\f[R]\&...] [\f[B]-f\f[R] \f[I]file\f[R]\&...] [\f[B]--file\f[R]=\f[I]file\f[R]\&...] [\f[I]file\f[R]\&...] .SH DESCRIPTION .PP dc(1) is an arbitrary-precision calculator. It uses a stack (reverse Polish notation) to store numbers and results of computations. Arithmetic operations pop arguments off of the stack and push the results. .PP If no files are given on the command-line, then dc(1) reads from \f[B]stdin\f[R] (see the \f[B]STDIN\f[R] section). Otherwise, those files are processed, and dc(1) will then exit. .PP If a user wants to set up a standard environment, they can use \f[B]DC_ENV_ARGS\f[R] (see the \f[B]ENVIRONMENT VARIABLES\f[R] section). For example, if a user wants the \f[B]scale\f[R] always set to \f[B]10\f[R], they can set \f[B]DC_ENV_ARGS\f[R] to \f[B]-e 10k\f[R], and this dc(1) will always start with a \f[B]scale\f[R] of \f[B]10\f[R]. .SH OPTIONS .PP The following are the options that dc(1) accepts. .TP \f[B]-h\f[R], \f[B]--help\f[R] Prints a usage message and quits. .TP \f[B]-v\f[R], \f[B]-V\f[R], \f[B]--version\f[R] Print the version information (copyright header) and exit. .TP \f[B]-i\f[R], \f[B]--interactive\f[R] Forces interactive mode. (See the \f[B]INTERACTIVE MODE\f[R] section.) .RS .PP This is a \f[B]non-portable extension\f[R]. .RE .TP \f[B]-L\f[R], \f[B]--no-line-length\f[R] Disables line length checking and prints numbers without backslashes and newlines. In other words, this option sets \f[B]BC_LINE_LENGTH\f[R] to \f[B]0\f[R] (see the \f[B]ENVIRONMENT VARIABLES\f[R] section). .RS .PP This is a \f[B]non-portable extension\f[R]. .RE .TP \f[B]-P\f[R], \f[B]--no-prompt\f[R] Disables the prompt in TTY mode. (The prompt is only enabled in TTY mode. See the \f[B]TTY MODE\f[R] section.) This is mostly for those users that do not want a prompt or are not used to having them in dc(1). Most of those users would want to put this option in \f[B]DC_ENV_ARGS\f[R]. .RS .PP These options override the \f[B]DC_PROMPT\f[R] and \f[B]DC_TTY_MODE\f[R] environment variables (see the \f[B]ENVIRONMENT VARIABLES\f[R] section). .PP This is a \f[B]non-portable extension\f[R]. .RE .TP \f[B]-R\f[R], \f[B]--no-read-prompt\f[R] Disables the read prompt in TTY mode. (The read prompt is only enabled in TTY mode. See the \f[B]TTY MODE\f[R] section.) This is mostly for those users that do not want a read prompt or are not used to having them in dc(1). Most of those users would want to put this option in \f[B]BC_ENV_ARGS\f[R] (see the \f[B]ENVIRONMENT VARIABLES\f[R] section). This option is also useful in hash bang lines of dc(1) scripts that prompt for user input. .RS .PP This option does not disable the regular prompt because the read prompt is only used when the \f[B]?\f[R] command is used. .PP These options \f[I]do\f[R] override the \f[B]DC_PROMPT\f[R] and \f[B]DC_TTY_MODE\f[R] environment variables (see the \f[B]ENVIRONMENT VARIABLES\f[R] section), but only for the read prompt. .PP This is a \f[B]non-portable extension\f[R]. .RE .TP \f[B]-x\f[R] \f[B]--extended-register\f[R] Enables extended register mode. See the \f[I]Extended Register Mode\f[R] subsection of the \f[B]REGISTERS\f[R] section for more information. .RS .PP This is a \f[B]non-portable extension\f[R]. .RE .TP \f[B]-z\f[R], \f[B]--leading-zeroes\f[R] Makes bc(1) print all numbers greater than \f[B]-1\f[R] and less than \f[B]1\f[R], and not equal to \f[B]0\f[R], with a leading zero. .RS .PP This can be set for individual numbers with the \f[B]plz(x)\f[R], plznl(x)**, \f[B]pnlz(x)\f[R], and \f[B]pnlznl(x)\f[R] functions in the extended math library (see the \f[B]LIBRARY\f[R] section). .PP This is a \f[B]non-portable extension\f[R]. .RE .TP \f[B]-e\f[R] \f[I]expr\f[R], \f[B]--expression\f[R]=\f[I]expr\f[R] Evaluates \f[I]expr\f[R]. If multiple expressions are given, they are evaluated in order. If files are given as well (see below), the expressions and files are evaluated in the order given. This means that if a file is given before an expression, the file is read in and evaluated first. .RS .PP If this option is given on the command-line (i.e., not in \f[B]DC_ENV_ARGS\f[R], see the \f[B]ENVIRONMENT VARIABLES\f[R] section), then after processing all expressions and files, dc(1) will exit, unless \f[B]-\f[R] (\f[B]stdin\f[R]) was given as an argument at least once to \f[B]-f\f[R] or \f[B]--file\f[R], whether on the command-line or in \f[B]DC_ENV_ARGS\f[R]. However, if any other \f[B]-e\f[R], \f[B]--expression\f[R], \f[B]-f\f[R], or \f[B]--file\f[R] arguments are given after \f[B]-f-\f[R] or equivalent is given, dc(1) will give a fatal error and exit. .PP This is a \f[B]non-portable extension\f[R]. .RE .TP \f[B]-f\f[R] \f[I]file\f[R], \f[B]--file\f[R]=\f[I]file\f[R] Reads in \f[I]file\f[R] and evaluates it, line by line, as though it were read through \f[B]stdin\f[R]. If expressions are also given (see above), the expressions are evaluated in the order given. .RS .PP If this option is given on the command-line (i.e., not in \f[B]DC_ENV_ARGS\f[R], see the \f[B]ENVIRONMENT VARIABLES\f[R] section), then after processing all expressions and files, dc(1) will exit, unless \f[B]-\f[R] (\f[B]stdin\f[R]) was given as an argument at least once to \f[B]-f\f[R] or \f[B]--file\f[R]. However, if any other \f[B]-e\f[R], \f[B]--expression\f[R], \f[B]-f\f[R], or \f[B]--file\f[R] arguments are given after \f[B]-f-\f[R] or equivalent is given, dc(1) will give a fatal error and exit. .PP This is a \f[B]non-portable extension\f[R]. .RE .PP All long options are \f[B]non-portable extensions\f[R]. .SH STDIN .PP If no files are given on the command-line and no files or expressions are given by the \f[B]-f\f[R], \f[B]--file\f[R], \f[B]-e\f[R], or \f[B]--expression\f[R] options, then dc(1) read from \f[B]stdin\f[R]. .PP However, there is a caveat to this. .PP First, \f[B]stdin\f[R] is evaluated a line at a time. The only exception to this is if a string has been finished, but not ended. This means that, except for escaped brackets, all brackets must be balanced before dc(1) parses and executes. .SH STDOUT .PP Any non-error output is written to \f[B]stdout\f[R]. In addition, if history (see the \f[B]HISTORY\f[R] section) and the prompt (see the \f[B]TTY MODE\f[R] section) are enabled, both are output to \f[B]stdout\f[R]. .PP \f[B]Note\f[R]: Unlike other dc(1) implementations, this dc(1) will issue a fatal error (see the \f[B]EXIT STATUS\f[R] section) if it cannot write to \f[B]stdout\f[R], so if \f[B]stdout\f[R] is closed, as in \f[B]dc >&-\f[R], it will quit with an error. This is done so that dc(1) can report problems when \f[B]stdout\f[R] is redirected to a file. .PP If there are scripts that depend on the behavior of other dc(1) implementations, it is recommended that those scripts be changed to redirect \f[B]stdout\f[R] to \f[B]/dev/null\f[R]. .SH STDERR .PP Any error output is written to \f[B]stderr\f[R]. .PP \f[B]Note\f[R]: Unlike other dc(1) implementations, this dc(1) will issue a fatal error (see the \f[B]EXIT STATUS\f[R] section) if it cannot write to \f[B]stderr\f[R], so if \f[B]stderr\f[R] is closed, as in \f[B]dc 2>&-\f[R], it will quit with an error. This is done so that dc(1) can exit with an error code when \f[B]stderr\f[R] is redirected to a file. .PP If there are scripts that depend on the behavior of other dc(1) implementations, it is recommended that those scripts be changed to redirect \f[B]stderr\f[R] to \f[B]/dev/null\f[R]. .SH SYNTAX .PP Each item in the input source code, either a number (see the \f[B]NUMBERS\f[R] section) or a command (see the \f[B]COMMANDS\f[R] section), is processed and executed, in order. Input is processed immediately when entered. .PP \f[B]ibase\f[R] is a register (see the \f[B]REGISTERS\f[R] section) that determines how to interpret constant numbers. It is the \[lq]input\[rq] base, or the number base used for interpreting input numbers. \f[B]ibase\f[R] is initially \f[B]10\f[R]. The max allowable value for \f[B]ibase\f[R] is \f[B]16\f[R]. The min allowable value for \f[B]ibase\f[R] is \f[B]2\f[R]. The max allowable value for \f[B]ibase\f[R] can be queried in dc(1) programs with the \f[B]T\f[R] command. .PP \f[B]obase\f[R] is a register (see the \f[B]REGISTERS\f[R] section) that determines how to output results. It is the \[lq]output\[rq] base, or the number base used for outputting numbers. \f[B]obase\f[R] is initially \f[B]10\f[R]. The max allowable value for \f[B]obase\f[R] is \f[B]DC_BASE_MAX\f[R] and can be queried with the \f[B]U\f[R] command. The min allowable value for \f[B]obase\f[R] is \f[B]2\f[R]. Values are output in the specified base. .PP The \f[I]scale\f[R] of an expression is the number of digits in the result of the expression right of the decimal point, and \f[B]scale\f[R] is a register (see the \f[B]REGISTERS\f[R] section) that sets the precision of any operations (with exceptions). \f[B]scale\f[R] is initially \f[B]0\f[R]. \f[B]scale\f[R] cannot be negative. The max allowable value for \f[B]scale\f[R] can be queried in dc(1) programs with the \f[B]V\f[R] command. .SS Comments .PP Comments go from \f[B]#\f[R] until, and not including, the next newline. This is a \f[B]non-portable extension\f[R]. .SH NUMBERS .PP Numbers are strings made up of digits, uppercase letters up to \f[B]F\f[R], and at most \f[B]1\f[R] period for a radix. Numbers can have up to \f[B]DC_NUM_MAX\f[R] digits. Uppercase letters are equal to \f[B]9\f[R] + their position in the alphabet (i.e., \f[B]A\f[R] equals \f[B]10\f[R], or \f[B]9+1\f[R]). If a digit or letter makes no sense with the current value of \f[B]ibase\f[R], they are set to the value of the highest valid digit in \f[B]ibase\f[R]. .PP Single-character numbers (i.e., \f[B]A\f[R] alone) take the value that they would have if they were valid digits, regardless of the value of \f[B]ibase\f[R]. This means that \f[B]A\f[R] alone always equals decimal \f[B]10\f[R] and \f[B]F\f[R] alone always equals decimal \f[B]15\f[R]. .SH COMMANDS .PP The valid commands are listed below. .SS Printing .PP These commands are used for printing. .TP \f[B]p\f[R] Prints the value on top of the stack, whether number or string, and prints a newline after. .RS .PP This does not alter the stack. .RE .TP \f[B]n\f[R] Prints the value on top of the stack, whether number or string, and pops it off of the stack. .TP \f[B]P\f[R] Pops a value off the stack. .RS .PP If the value is a number, it is truncated and the absolute value of the result is printed as though \f[B]obase\f[R] is \f[B]256\f[R] and each digit is interpreted as an 8-bit ASCII character, making it a byte stream. .PP If the value is a string, it is printed without a trailing newline. .PP This is a \f[B]non-portable extension\f[R]. .RE .TP \f[B]f\f[R] Prints the entire contents of the stack, in order from newest to oldest, without altering anything. .RS .PP Users should use this command when they get lost. .RE .SS Arithmetic .PP These are the commands used for arithmetic. .TP \f[B]+\f[R] The top two values are popped off the stack, added, and the result is pushed onto the stack. The \f[I]scale\f[R] of the result is equal to the max \f[I]scale\f[R] of both operands. .TP \f[B]-\f[R] The top two values are popped off the stack, subtracted, and the result is pushed onto the stack. The \f[I]scale\f[R] of the result is equal to the max \f[I]scale\f[R] of both operands. .TP \f[B]*\f[R] The top two values are popped off the stack, multiplied, and the result is pushed onto the stack. If \f[B]a\f[R] is the \f[I]scale\f[R] of the first expression and \f[B]b\f[R] is the \f[I]scale\f[R] of the second expression, the \f[I]scale\f[R] of the result is equal to \f[B]min(a+b,max(scale,a,b))\f[R] where \f[B]min()\f[R] and \f[B]max()\f[R] return the obvious values. .TP \f[B]/\f[R] The top two values are popped off the stack, divided, and the result is pushed onto the stack. The \f[I]scale\f[R] of the result is equal to \f[B]scale\f[R]. .RS .PP The first value popped off of the stack must be non-zero. .RE .TP \f[B]%\f[R] The top two values are popped off the stack, remaindered, and the result is pushed onto the stack. .RS .PP Remaindering is equivalent to 1) Computing \f[B]a/b\f[R] to current \f[B]scale\f[R], and 2) Using the result of step 1 to calculate \f[B]a-(a/b)*b\f[R] to \f[I]scale\f[R] \f[B]max(scale+scale(b),scale(a))\f[R]. .PP The first value popped off of the stack must be non-zero. .RE .TP \f[B]\[ti]\f[R] The top two values are popped off the stack, divided and remaindered, and the results (divided first, remainder second) are pushed onto the stack. This is equivalent to \f[B]x y / x y %\f[R] except that \f[B]x\f[R] and \f[B]y\f[R] are only evaluated once. .RS .PP The first value popped off of the stack must be non-zero. .PP This is a \f[B]non-portable extension\f[R]. .RE .TP \f[B]\[ha]\f[R] The top two values are popped off the stack, the second is raised to the power of the first, and the result is pushed onto the stack. The \f[I]scale\f[R] of the result is equal to \f[B]scale\f[R]. .RS .PP The first value popped off of the stack must be an integer, and if that value is negative, the second value popped off of the stack must be non-zero. .RE .TP \f[B]v\f[R] The top value is popped off the stack, its square root is computed, and the result is pushed onto the stack. The \f[I]scale\f[R] of the result is equal to \f[B]scale\f[R]. .RS .PP The value popped off of the stack must be non-negative. .RE .TP \f[B]_\f[R] If this command \f[I]immediately\f[R] precedes a number (i.e., no spaces or other commands), then that number is input as a negative number. .RS .PP Otherwise, the top value on the stack is popped and copied, and the copy is negated and pushed onto the stack. This behavior without a number is a \f[B]non-portable extension\f[R]. .RE .TP \f[B]b\f[R] The top value is popped off the stack, and if it is zero, it is pushed back onto the stack. Otherwise, its absolute value is pushed onto the stack. .RS .PP This is a \f[B]non-portable extension\f[R]. .RE .TP \f[B]|\f[R] The top three values are popped off the stack, a modular exponentiation is computed, and the result is pushed onto the stack. .RS .PP The first value popped is used as the reduction modulus and must be an integer and non-zero. The second value popped is used as the exponent and must be an integer and non-negative. The third value popped is the base and must be an integer. .PP This is a \f[B]non-portable extension\f[R]. .RE .TP \f[B]G\f[R] The top two values are popped off of the stack, they are compared, and a \f[B]1\f[R] is pushed if they are equal, or \f[B]0\f[R] otherwise. .RS .PP This is a \f[B]non-portable extension\f[R]. .RE .TP \f[B]N\f[R] The top value is popped off of the stack, and if it a \f[B]0\f[R], a \f[B]1\f[R] is pushed; otherwise, a \f[B]0\f[R] is pushed. .RS .PP This is a \f[B]non-portable extension\f[R]. .RE .TP \f[B](\f[R] The top two values are popped off of the stack, they are compared, and a \f[B]1\f[R] is pushed if the first is less than the second, or \f[B]0\f[R] otherwise. .RS .PP This is a \f[B]non-portable extension\f[R]. .RE .TP \f[B]{\f[R] The top two values are popped off of the stack, they are compared, and a \f[B]1\f[R] is pushed if the first is less than or equal to the second, or \f[B]0\f[R] otherwise. .RS .PP This is a \f[B]non-portable extension\f[R]. .RE .TP \f[B])\f[R] The top two values are popped off of the stack, they are compared, and a \f[B]1\f[R] is pushed if the first is greater than the second, or \f[B]0\f[R] otherwise. .RS .PP This is a \f[B]non-portable extension\f[R]. .RE .TP \f[B]}\f[R] The top two values are popped off of the stack, they are compared, and a \f[B]1\f[R] is pushed if the first is greater than or equal to the second, or \f[B]0\f[R] otherwise. .RS .PP This is a \f[B]non-portable extension\f[R]. .RE .TP \f[B]M\f[R] The top two values are popped off of the stack. If they are both non-zero, a \f[B]1\f[R] is pushed onto the stack. If either of them is zero, or both of them are, then a \f[B]0\f[R] is pushed onto the stack. .RS .PP This is like the \f[B]&&\f[R] operator in bc(1), and it is \f[I]not\f[R] a short-circuit operator. .PP This is a \f[B]non-portable extension\f[R]. .RE .TP \f[B]m\f[R] The top two values are popped off of the stack. If at least one of them is non-zero, a \f[B]1\f[R] is pushed onto the stack. If both of them are zero, then a \f[B]0\f[R] is pushed onto the stack. .RS .PP This is like the \f[B]||\f[R] operator in bc(1), and it is \f[I]not\f[R] a short-circuit operator. .PP This is a \f[B]non-portable extension\f[R]. .RE .SS Stack Control .PP These commands control the stack. .TP \f[B]c\f[R] Removes all items from (\[lq]clears\[rq]) the stack. .TP \f[B]d\f[R] Copies the item on top of the stack (\[lq]duplicates\[rq]) and pushes the copy onto the stack. .TP \f[B]r\f[R] Swaps (\[lq]reverses\[rq]) the two top items on the stack. .TP \f[B]R\f[R] Pops (\[lq]removes\[rq]) the top value from the stack. .SS Register Control .PP These commands control registers (see the \f[B]REGISTERS\f[R] section). .TP \f[B]s\f[R]\f[I]r\f[R] Pops the value off the top of the stack and stores it into register \f[I]r\f[R]. .TP \f[B]l\f[R]\f[I]r\f[R] Copies the value in register \f[I]r\f[R] and pushes it onto the stack. This does not alter the contents of \f[I]r\f[R]. .TP \f[B]S\f[R]\f[I]r\f[R] Pops the value off the top of the (main) stack and pushes it onto the stack of register \f[I]r\f[R]. The previous value of the register becomes inaccessible. .TP \f[B]L\f[R]\f[I]r\f[R] Pops the value off the top of the stack for register \f[I]r\f[R] and push it onto the main stack. The previous value in the stack for register \f[I]r\f[R], if any, is now accessible via the \f[B]l\f[R]\f[I]r\f[R] command. .SS Parameters .PP These commands control the values of \f[B]ibase\f[R], \f[B]obase\f[R], and \f[B]scale\f[R]. Also see the \f[B]SYNTAX\f[R] section. .TP \f[B]i\f[R] Pops the value off of the top of the stack and uses it to set \f[B]ibase\f[R], which must be between \f[B]2\f[R] and \f[B]16\f[R], inclusive. .RS .PP If the value on top of the stack has any \f[I]scale\f[R], the \f[I]scale\f[R] is ignored. .RE .TP \f[B]o\f[R] Pops the value off of the top of the stack and uses it to set \f[B]obase\f[R], which must be between \f[B]2\f[R] and \f[B]DC_BASE_MAX\f[R], inclusive (see the \f[B]LIMITS\f[R] section). .RS .PP If the value on top of the stack has any \f[I]scale\f[R], the \f[I]scale\f[R] is ignored. .RE .TP \f[B]k\f[R] Pops the value off of the top of the stack and uses it to set \f[B]scale\f[R], which must be non-negative. .RS .PP If the value on top of the stack has any \f[I]scale\f[R], the \f[I]scale\f[R] is ignored. .RE .TP \f[B]I\f[R] Pushes the current value of \f[B]ibase\f[R] onto the main stack. .TP \f[B]O\f[R] Pushes the current value of \f[B]obase\f[R] onto the main stack. .TP \f[B]K\f[R] Pushes the current value of \f[B]scale\f[R] onto the main stack. .TP \f[B]T\f[R] Pushes the maximum allowable value of \f[B]ibase\f[R] onto the main stack. .RS .PP This is a \f[B]non-portable extension\f[R]. .RE .TP \f[B]U\f[R] Pushes the maximum allowable value of \f[B]obase\f[R] onto the main stack. .RS .PP This is a \f[B]non-portable extension\f[R]. .RE .TP \f[B]V\f[R] Pushes the maximum allowable value of \f[B]scale\f[R] onto the main stack. .RS .PP This is a \f[B]non-portable extension\f[R]. .RE .SS Strings .PP The following commands control strings. .PP dc(1) can work with both numbers and strings, and registers (see the \f[B]REGISTERS\f[R] section) can hold both strings and numbers. dc(1) always knows whether the contents of a register are a string or a number. .PP While arithmetic operations have to have numbers, and will print an error if given a string, other commands accept strings. .PP Strings can also be executed as macros. For example, if the string \f[B][1pR]\f[R] is executed as a macro, then the code \f[B]1pR\f[R] is executed, meaning that the \f[B]1\f[R] will be printed with a newline after and then popped from the stack. .TP \f[B][\f[R]\f[I]characters\f[R]\f[B]]\f[R] Makes a string containing \f[I]characters\f[R] and pushes it onto the stack. .RS .PP If there are brackets (\f[B][\f[R] and \f[B]]\f[R]) in the string, then they must be balanced. Unbalanced brackets can be escaped using a backslash (\f[B]\[rs]\f[R]) character. .PP If there is a backslash character in the string, the character after it (even another backslash) is put into the string verbatim, but the (first) backslash is not. .RE .TP \f[B]a\f[R] The value on top of the stack is popped. .RS .PP If it is a number, it is truncated and its absolute value is taken. The result mod \f[B]256\f[R] is calculated. If that result is \f[B]0\f[R], push an empty string; otherwise, push a one-character string where the character is the result of the mod interpreted as an ASCII character. .PP If it is a string, then a new string is made. If the original string is empty, the new string is empty. If it is not, then the first character of the original string is used to create the new string as a one-character string. The new string is then pushed onto the stack. .PP This is a \f[B]non-portable extension\f[R]. .RE .TP \f[B]x\f[R] Pops a value off of the top of the stack. .RS .PP If it is a number, it is pushed back onto the stack. .PP If it is a string, it is executed as a macro. .PP This behavior is the norm whenever a macro is executed, whether by this command or by the conditional execution commands below. .RE .TP \f[B]>\f[R]\f[I]r\f[R] Pops two values off of the stack that must be numbers and compares them. If the first value is greater than the second, then the contents of register \f[I]r\f[R] are executed. .RS .PP For example, \f[B]0 1>a\f[R] will execute the contents of register \f[B]a\f[R], and \f[B]1 0>a\f[R] will not. .PP If either or both of the values are not numbers, dc(1) will raise an error and reset (see the \f[B]RESET\f[R] section). .RE .TP \f[B]>\f[R]\f[I]r\f[R]\f[B]e\f[R]\f[I]s\f[R] Like the above, but will execute register \f[I]s\f[R] if the comparison fails. .RS .PP If either or both of the values are not numbers, dc(1) will raise an error and reset (see the \f[B]RESET\f[R] section). .PP This is a \f[B]non-portable extension\f[R]. .RE .TP \f[B]!>\f[R]\f[I]r\f[R] Pops two values off of the stack that must be numbers and compares them. If the first value is not greater than the second (less than or equal to), then the contents of register \f[I]r\f[R] are executed. .RS .PP If either or both of the values are not numbers, dc(1) will raise an error and reset (see the \f[B]RESET\f[R] section). .RE .TP \f[B]!>\f[R]\f[I]r\f[R]\f[B]e\f[R]\f[I]s\f[R] Like the above, but will execute register \f[I]s\f[R] if the comparison fails. .RS .PP If either or both of the values are not numbers, dc(1) will raise an error and reset (see the \f[B]RESET\f[R] section). .PP This is a \f[B]non-portable extension\f[R]. .RE .TP \f[B]<\f[R]\f[I]r\f[R] Pops two values off of the stack that must be numbers and compares them. If the first value is less than the second, then the contents of register \f[I]r\f[R] are executed. .RS .PP If either or both of the values are not numbers, dc(1) will raise an error and reset (see the \f[B]RESET\f[R] section). .RE .TP \f[B]<\f[R]\f[I]r\f[R]\f[B]e\f[R]\f[I]s\f[R] Like the above, but will execute register \f[I]s\f[R] if the comparison fails. .RS .PP If either or both of the values are not numbers, dc(1) will raise an error and reset (see the \f[B]RESET\f[R] section). .PP This is a \f[B]non-portable extension\f[R]. .RE .TP \f[B]!<\f[R]\f[I]r\f[R] Pops two values off of the stack that must be numbers and compares them. If the first value is not less than the second (greater than or equal to), then the contents of register \f[I]r\f[R] are executed. .RS .PP If either or both of the values are not numbers, dc(1) will raise an error and reset (see the \f[B]RESET\f[R] section). .RE .TP \f[B]!<\f[R]\f[I]r\f[R]\f[B]e\f[R]\f[I]s\f[R] Like the above, but will execute register \f[I]s\f[R] if the comparison fails. .RS .PP If either or both of the values are not numbers, dc(1) will raise an error and reset (see the \f[B]RESET\f[R] section). .PP This is a \f[B]non-portable extension\f[R]. .RE .TP \f[B]=\f[R]\f[I]r\f[R] Pops two values off of the stack that must be numbers and compares them. If the first value is equal to the second, then the contents of register \f[I]r\f[R] are executed. .RS .PP If either or both of the values are not numbers, dc(1) will raise an error and reset (see the \f[B]RESET\f[R] section). .RE .TP \f[B]=\f[R]\f[I]r\f[R]\f[B]e\f[R]\f[I]s\f[R] Like the above, but will execute register \f[I]s\f[R] if the comparison fails. .RS .PP If either or both of the values are not numbers, dc(1) will raise an error and reset (see the \f[B]RESET\f[R] section). .PP This is a \f[B]non-portable extension\f[R]. .RE .TP \f[B]!=\f[R]\f[I]r\f[R] Pops two values off of the stack that must be numbers and compares them. If the first value is not equal to the second, then the contents of register \f[I]r\f[R] are executed. .RS .PP If either or both of the values are not numbers, dc(1) will raise an error and reset (see the \f[B]RESET\f[R] section). .RE .TP \f[B]!=\f[R]\f[I]r\f[R]\f[B]e\f[R]\f[I]s\f[R] Like the above, but will execute register \f[I]s\f[R] if the comparison fails. .RS .PP If either or both of the values are not numbers, dc(1) will raise an error and reset (see the \f[B]RESET\f[R] section). .PP This is a \f[B]non-portable extension\f[R]. .RE .TP \f[B]?\f[R] Reads a line from the \f[B]stdin\f[R] and executes it. This is to allow macros to request input from users. .TP \f[B]q\f[R] During execution of a macro, this exits the execution of that macro and the execution of the macro that executed it. If there are no macros, or only one macro executing, dc(1) exits. .TP \f[B]Q\f[R] Pops a value from the stack which must be non-negative and is used the number of macro executions to pop off of the execution stack. If the number of levels to pop is greater than the number of executing macros, dc(1) exits. .TP \f[B],\f[R] Pushes the depth of the execution stack onto the stack. The execution stack is the stack of string executions. The number that is pushed onto the stack is exactly as many as is needed to make dc(1) exit with the \f[B]Q\f[R] command, so the sequence \f[B],Q\f[R] will make dc(1) exit. .SS Status .PP These commands query status of the stack or its top value. .TP \f[B]Z\f[R] Pops a value off of the stack. .RS .PP If it is a number, calculates the number of significant decimal digits it has and pushes the result. It will push \f[B]1\f[R] if the argument is \f[B]0\f[R] with no decimal places. .PP If it is a string, pushes the number of characters the string has. .RE .TP \f[B]X\f[R] Pops a value off of the stack. .RS .PP If it is a number, pushes the \f[I]scale\f[R] of the value onto the stack. .PP If it is a string, pushes \f[B]0\f[R]. .RE .TP \f[B]z\f[R] Pushes the current depth of the stack (before execution of this command) onto the stack. .TP \f[B]y\f[R]\f[I]r\f[R] Pushes the current stack depth of the register \f[I]r\f[R] onto the main stack. .RS .PP Because each register has a depth of \f[B]1\f[R] (with the value \f[B]0\f[R] in the top item) when dc(1) starts, dc(1) requires that each register\[cq]s stack must always have at least one item; dc(1) will give an error and reset otherwise (see the \f[B]RESET\f[R] section). This means that this command will never push \f[B]0\f[R]. .PP This is a \f[B]non-portable extension\f[R]. .RE .SS Arrays .PP These commands manipulate arrays. .TP \f[B]:\f[R]\f[I]r\f[R] Pops the top two values off of the stack. The second value will be stored in the array \f[I]r\f[R] (see the \f[B]REGISTERS\f[R] section), indexed by the first value. .TP \f[B];\f[R]\f[I]r\f[R] Pops the value on top of the stack and uses it as an index into the array \f[I]r\f[R]. The selected value is then pushed onto the stack. .TP \f[B]Y\f[R]\f[I]r\f[R] Pushes the length of the array \f[I]r\f[R] onto the stack. .RS .PP This is a \f[B]non-portable extension\f[R]. .RE .SS Global Settings .PP These commands retrieve global settings. These are the only commands that require multiple specific characters, and all of them begin with the letter \f[B]g\f[R]. Only the characters below are allowed after the character \f[B]g\f[R]; any other character produces a parse error (see the \f[B]ERRORS\f[R] section). .TP \f[B]gl\f[R] Pushes the line length set by \f[B]DC_LINE_LENGTH\f[R] (see the \f[B]ENVIRONMENT VARIABLES\f[R] section) onto the stack. .TP \f[B]gz\f[R] Pushes \f[B]0\f[R] onto the stack if the leading zero setting has not been enabled with the \f[B]-z\f[R] or \f[B]--leading-zeroes\f[R] options (see the \f[B]OPTIONS\f[R] section), non-zero otherwise. .SH REGISTERS .PP Registers are names that can store strings, numbers, and arrays. (Number/string registers do not interfere with array registers.) .PP Each register is also its own stack, so the current register value is the top of the stack for the register. All registers, when first referenced, have one value (\f[B]0\f[R]) in their stack, and it is a runtime error to attempt to pop that item off of the register stack. .PP In non-extended register mode, a register name is just the single character that follows any command that needs a register name. The only exceptions are: a newline (\f[B]`\[rs]n'\f[R]) and a left bracket (\f[B]`['\f[R]); it is a parse error for a newline or a left bracket to be used as a register name. .SS Extended Register Mode .PP Unlike most other dc(1) implentations, this dc(1) provides nearly unlimited amounts of registers, if extended register mode is enabled. .PP If extended register mode is enabled (\f[B]-x\f[R] or \f[B]--extended-register\f[R] command-line arguments are given), then normal single character registers are used \f[I]unless\f[R] the character immediately following a command that needs a register name is a space (according to \f[B]isspace()\f[R]) and not a newline (\f[B]`\[rs]n'\f[R]). .PP In that case, the register name is found according to the regex \f[B][a-z][a-z0-9_]*\f[R] (like bc(1) identifiers), and it is a parse error if the next non-space characters do not match that regex. .SH RESET .PP When dc(1) encounters an error or a signal that it has a non-default handler for, it resets. This means that several things happen. .PP First, any macros that are executing are stopped and popped off the stack. The behavior is not unlike that of exceptions in programming languages. Then the execution point is set so that any code waiting to execute (after all macros returned) is skipped. .PP Thus, when dc(1) resets, it skips any remaining code waiting to be executed. Then, if it is interactive mode, and the error was not a fatal error (see the \f[B]EXIT STATUS\f[R] section), it asks for more input; otherwise, it exits with the appropriate return code. .SH PERFORMANCE .PP Most dc(1) implementations use \f[B]char\f[R] types to calculate the value of \f[B]1\f[R] decimal digit at a time, but that can be slow. This dc(1) does something different. .PP It uses large integers to calculate more than \f[B]1\f[R] decimal digit at a time. If built in a environment where \f[B]DC_LONG_BIT\f[R] (see the \f[B]LIMITS\f[R] section) is \f[B]64\f[R], then each integer has \f[B]9\f[R] decimal digits. If built in an environment where \f[B]DC_LONG_BIT\f[R] is \f[B]32\f[R] then each integer has \f[B]4\f[R] decimal digits. This value (the number of decimal digits per large integer) is called \f[B]DC_BASE_DIGS\f[R]. .PP In addition, this dc(1) uses an even larger integer for overflow checking. This integer type depends on the value of \f[B]DC_LONG_BIT\f[R], but is always at least twice as large as the integer type used to store digits. .SH LIMITS .PP The following are the limits on dc(1): .TP \f[B]DC_LONG_BIT\f[R] The number of bits in the \f[B]long\f[R] type in the environment where dc(1) was built. This determines how many decimal digits can be stored in a single large integer (see the \f[B]PERFORMANCE\f[R] section). .TP \f[B]DC_BASE_DIGS\f[R] The number of decimal digits per large integer (see the \f[B]PERFORMANCE\f[R] section). Depends on \f[B]DC_LONG_BIT\f[R]. .TP \f[B]DC_BASE_POW\f[R] The max decimal number that each large integer can store (see \f[B]DC_BASE_DIGS\f[R]) plus \f[B]1\f[R]. Depends on \f[B]DC_BASE_DIGS\f[R]. .TP \f[B]DC_OVERFLOW_MAX\f[R] The max number that the overflow type (see the \f[B]PERFORMANCE\f[R] section) can hold. Depends on \f[B]DC_LONG_BIT\f[R]. .TP \f[B]DC_BASE_MAX\f[R] The maximum output base. Set at \f[B]DC_BASE_POW\f[R]. .TP \f[B]DC_DIM_MAX\f[R] The maximum size of arrays. Set at \f[B]SIZE_MAX-1\f[R]. .TP \f[B]DC_SCALE_MAX\f[R] The maximum \f[B]scale\f[R]. Set at \f[B]DC_OVERFLOW_MAX-1\f[R]. .TP \f[B]DC_STRING_MAX\f[R] The maximum length of strings. Set at \f[B]DC_OVERFLOW_MAX-1\f[R]. .TP \f[B]DC_NAME_MAX\f[R] The maximum length of identifiers. Set at \f[B]DC_OVERFLOW_MAX-1\f[R]. .TP \f[B]DC_NUM_MAX\f[R] The maximum length of a number (in decimal digits), which includes digits after the decimal point. Set at \f[B]DC_OVERFLOW_MAX-1\f[R]. .TP Exponent The maximum allowable exponent (positive or negative). Set at \f[B]DC_OVERFLOW_MAX\f[R]. .TP Number of vars The maximum number of vars/arrays. Set at \f[B]SIZE_MAX-1\f[R]. .PP These limits are meant to be effectively non-existent; the limits are so large (at least on 64-bit machines) that there should not be any point at which they become a problem. In fact, memory should be exhausted before these limits should be hit. .SH ENVIRONMENT VARIABLES .PP dc(1) recognizes the following environment variables: .TP \f[B]DC_ENV_ARGS\f[R] This is another way to give command-line arguments to dc(1). They should be in the same format as all other command-line arguments. These are always processed first, so any files given in \f[B]DC_ENV_ARGS\f[R] will be processed before arguments and files given on the command-line. This gives the user the ability to set up \[lq]standard\[rq] options and files to be used at every invocation. The most useful thing for such files to contain would be useful functions that the user might want every time dc(1) runs. Another use would be to use the \f[B]-e\f[R] option to set \f[B]scale\f[R] to a value other than \f[B]0\f[R]. .RS .PP The code that parses \f[B]DC_ENV_ARGS\f[R] will correctly handle quoted arguments, but it does not understand escape sequences. For example, the string \f[B]\[lq]/home/gavin/some dc file.dc\[rq]\f[R] will be correctly parsed, but the string \f[B]\[lq]/home/gavin/some \[dq]dc\[dq] file.dc\[rq]\f[R] will include the backslashes. .PP The quote parsing will handle either kind of quotes, \f[B]\[cq]\f[R] or \f[B]\[lq]\f[R]. Thus, if you have a file with any number of single quotes in the name, you can use double quotes as the outside quotes, as in \f[B]\[lq]some `dc' file.dc\[rq]\f[R], and vice versa if you have a file with double quotes. However, handling a file with both kinds of quotes in \f[B]DC_ENV_ARGS\f[R] is not supported due to the complexity of the parsing, though such files are still supported on the command-line where the parsing is done by the shell. .RE .TP \f[B]DC_LINE_LENGTH\f[R] If this environment variable exists and contains an integer that is greater than \f[B]1\f[R] and is less than \f[B]UINT16_MAX\f[R] (\f[B]2\[ha]16-1\f[R]), dc(1) will output lines to that length, including the backslash newline combo. The default line length is \f[B]70\f[R]. .RS .PP The special value of \f[B]0\f[R] will disable line length checking and print numbers without regard to line length and without backslashes and newlines. .RE .TP \f[B]DC_SIGINT_RESET\f[R] If dc(1) is not in interactive mode (see the \f[B]INTERACTIVE MODE\f[R] section), then this environment variable has no effect because dc(1) exits on \f[B]SIGINT\f[R] when not in interactive mode. .RS .PP However, when dc(1) is in interactive mode, then if this environment variable exists and contains an integer, a non-zero value makes dc(1) reset on \f[B]SIGINT\f[R], rather than exit, and zero makes dc(1) exit. If this environment variable exists and is \f[I]not\f[R] an integer, then dc(1) will exit on \f[B]SIGINT\f[R]. .PP This environment variable overrides the default, which can be queried with the \f[B]-h\f[R] or \f[B]--help\f[R] options. .RE .TP \f[B]DC_TTY_MODE\f[R] If TTY mode is \f[I]not\f[R] available (see the \f[B]TTY MODE\f[R] section), then this environment variable has no effect. .RS .PP However, when TTY mode is available, then if this environment variable exists and contains an integer, then a non-zero value makes dc(1) use TTY mode, and zero makes dc(1) not use TTY mode. .PP This environment variable overrides the default, which can be queried with the \f[B]-h\f[R] or \f[B]--help\f[R] options. .RE .TP \f[B]DC_PROMPT\f[R] If TTY mode is \f[I]not\f[R] available (see the \f[B]TTY MODE\f[R] section), then this environment variable has no effect. .RS .PP However, when TTY mode is available, then if this environment variable exists and contains an integer, a non-zero value makes dc(1) use a prompt, and zero or a non-integer makes dc(1) not use a prompt. If this environment variable does not exist and \f[B]DC_TTY_MODE\f[R] does, then the value of the \f[B]DC_TTY_MODE\f[R] environment variable is used. .PP This environment variable and the \f[B]DC_TTY_MODE\f[R] environment variable override the default, which can be queried with the \f[B]-h\f[R] or \f[B]--help\f[R] options. .RE +.TP +\f[B]DC_EXPR_EXIT\f[R] +If any expressions or expression files are given on the command-line +with \f[B]-e\f[R], \f[B]--expression\f[R], \f[B]-f\f[R], or +\f[B]--file\f[R], then if this environment variable exists and contains +an integer, a non-zero value makes dc(1) exit after executing the +expressions and expression files, and a non-zero value makes dc(1) not +exit. +.RS +.PP +This environment variable overrides the default, which can be queried +with the \f[B]-h\f[R] or \f[B]--help\f[R] options. +.RE .SH EXIT STATUS .PP dc(1) returns the following exit statuses: .TP \f[B]0\f[R] No error. .TP \f[B]1\f[R] A math error occurred. This follows standard practice of using \f[B]1\f[R] for expected errors, since math errors will happen in the process of normal execution. .RS .PP Math errors include divide by \f[B]0\f[R], taking the square root of a negative number, attempting to convert a negative number to a hardware integer, overflow when converting a number to a hardware integer, overflow when calculating the size of a number, and attempting to use a non-integer where an integer is required. .PP Converting to a hardware integer happens for the second operand of the power (\f[B]\[ha]\f[R]) operator. .RE .TP \f[B]2\f[R] A parse error occurred. .RS .PP Parse errors include unexpected \f[B]EOF\f[R], using an invalid character, failing to find the end of a string or comment, and using a token where it is invalid. .RE .TP \f[B]3\f[R] A runtime error occurred. .RS .PP Runtime errors include assigning an invalid number to any global (\f[B]ibase\f[R], \f[B]obase\f[R], or \f[B]scale\f[R]), giving a bad expression to a \f[B]read()\f[R] call, calling \f[B]read()\f[R] inside of a \f[B]read()\f[R] call, type errors (including attempting to execute a number), and attempting an operation when the stack has too few elements. .RE .TP \f[B]4\f[R] A fatal error occurred. .RS .PP Fatal errors include memory allocation errors, I/O errors, failing to open files, attempting to use files that do not have only ASCII characters (dc(1) only accepts ASCII characters), attempting to open a directory as a file, and giving invalid command-line options. .RE .PP The exit status \f[B]4\f[R] is special; when a fatal error occurs, dc(1) always exits and returns \f[B]4\f[R], no matter what mode dc(1) is in. .PP The other statuses will only be returned when dc(1) is not in interactive mode (see the \f[B]INTERACTIVE MODE\f[R] section), since dc(1) resets its state (see the \f[B]RESET\f[R] section) and accepts more input when one of those errors occurs in interactive mode. This is also the case when interactive mode is forced by the \f[B]-i\f[R] flag or \f[B]--interactive\f[R] option. .PP These exit statuses allow dc(1) to be used in shell scripting with error checking, and its normal behavior can be forced by using the \f[B]-i\f[R] flag or \f[B]--interactive\f[R] option. .SH INTERACTIVE MODE .PP Like bc(1), dc(1) has an interactive mode and a non-interactive mode. Interactive mode is turned on automatically when both \f[B]stdin\f[R] and \f[B]stdout\f[R] are hooked to a terminal, but the \f[B]-i\f[R] flag and \f[B]--interactive\f[R] option can turn it on in other situations. .PP In interactive mode, dc(1) attempts to recover from errors (see the \f[B]RESET\f[R] section), and in normal execution, flushes \f[B]stdout\f[R] as soon as execution is done for the current input. dc(1) may also reset on \f[B]SIGINT\f[R] instead of exit, depending on the contents of, or default for, the \f[B]DC_SIGINT_RESET\f[R] environment variable (see the \f[B]ENVIRONMENT VARIABLES\f[R] section). .SH TTY MODE .PP If \f[B]stdin\f[R], \f[B]stdout\f[R], and \f[B]stderr\f[R] are all connected to a TTY, then \[lq]TTY mode\[rq] is considered to be available, and thus, dc(1) can turn on TTY mode, subject to some settings. .PP If there is the environment variable \f[B]DC_TTY_MODE\f[R] in the environment (see the \f[B]ENVIRONMENT VARIABLES\f[R] section), then if that environment variable contains a non-zero integer, dc(1) will turn on TTY mode when \f[B]stdin\f[R], \f[B]stdout\f[R], and \f[B]stderr\f[R] are all connected to a TTY. If the \f[B]DC_TTY_MODE\f[R] environment variable exists but is \f[I]not\f[R] a non-zero integer, then dc(1) will not turn TTY mode on. .PP If the environment variable \f[B]DC_TTY_MODE\f[R] does \f[I]not\f[R] exist, the default setting is used. The default setting can be queried with the \f[B]-h\f[R] or \f[B]--help\f[R] options. .PP TTY mode is different from interactive mode because interactive mode is required in the bc(1) specification (https://pubs.opengroup.org/onlinepubs/9699919799/utilities/bc.html), and interactive mode requires only \f[B]stdin\f[R] and \f[B]stdout\f[R] to be connected to a terminal. .SS Prompt .PP If TTY mode is available, then a prompt can be enabled. Like TTY mode itself, it can be turned on or off with an environment variable: \f[B]DC_PROMPT\f[R] (see the \f[B]ENVIRONMENT VARIABLES\f[R] section). .PP If the environment variable \f[B]DC_PROMPT\f[R] exists and is a non-zero integer, then the prompt is turned on when \f[B]stdin\f[R], \f[B]stdout\f[R], and \f[B]stderr\f[R] are connected to a TTY and the \f[B]-P\f[R] and \f[B]--no-prompt\f[R] options were not used. The read prompt will be turned on under the same conditions, except that the \f[B]-R\f[R] and \f[B]--no-read-prompt\f[R] options must also not be used. .PP However, if \f[B]DC_PROMPT\f[R] does not exist, the prompt can be enabled or disabled with the \f[B]DC_TTY_MODE\f[R] environment variable, the \f[B]-P\f[R] and \f[B]--no-prompt\f[R] options, and the \f[B]-R\f[R] and \f[B]--no-read-prompt\f[R] options. See the \f[B]ENVIRONMENT VARIABLES\f[R] and \f[B]OPTIONS\f[R] sections for more details. .SH SIGNAL HANDLING .PP Sending a \f[B]SIGINT\f[R] will cause dc(1) to do one of two things. .PP If dc(1) is not in interactive mode (see the \f[B]INTERACTIVE MODE\f[R] section), or the \f[B]DC_SIGINT_RESET\f[R] environment variable (see the \f[B]ENVIRONMENT VARIABLES\f[R] section), or its default, is either not an integer or it is zero, dc(1) will exit. .PP However, if dc(1) is in interactive mode, and the \f[B]DC_SIGINT_RESET\f[R] or its default is an integer and non-zero, then dc(1) will stop executing the current input and reset (see the \f[B]RESET\f[R] section) upon receiving a \f[B]SIGINT\f[R]. .PP Note that \[lq]current input\[rq] can mean one of two things. If dc(1) is processing input from \f[B]stdin\f[R] in interactive mode, it will ask for more input. If dc(1) is processing input from a file in interactive mode, it will stop processing the file and start processing the next file, if one exists, or ask for input from \f[B]stdin\f[R] if no other file exists. .PP This means that if a \f[B]SIGINT\f[R] is sent to dc(1) as it is executing a file, it can seem as though dc(1) did not respond to the signal since it will immediately start executing the next file. This is by design; most files that users execute when interacting with dc(1) have function definitions, which are quick to parse. If a file takes a long time to execute, there may be a bug in that file. The rest of the files could still be executed without problem, allowing the user to continue. .PP \f[B]SIGTERM\f[R] and \f[B]SIGQUIT\f[R] cause dc(1) to clean up and exit, and it uses the default handler for all other signals. .SH LOCALES .PP This dc(1) ships with support for adding error messages for different locales and thus, supports \f[B]LC_MESSAGES\f[R]. .SH SEE ALSO .PP bc(1) .SH STANDARDS .PP The dc(1) utility operators are compliant with the operators in the bc(1) IEEE Std 1003.1-2017 (\[lq]POSIX.1-2017\[rq]) (https://pubs.opengroup.org/onlinepubs/9699919799/utilities/bc.html) specification. .SH BUGS .PP None are known. Report bugs at https://git.yzena.com/gavin/bc. .SH AUTHOR .PP Gavin D. Howard and contributors. diff --git a/contrib/bc/manuals/dc/EH.1.md b/contrib/bc/manuals/dc/EH.1.md index 06ec59d4b3f7..459f8ac12e7e 100644 --- a/contrib/bc/manuals/dc/EH.1.md +++ b/contrib/bc/manuals/dc/EH.1.md @@ -1,1194 +1,1205 @@ # Name dc - arbitrary-precision decimal reverse-Polish notation calculator # SYNOPSIS **dc** [**-hiPRvVx**] [**-\-version**] [**-\-help**] [**-\-interactive**] [**-\-no-prompt**] [**-\-no-read-prompt**] [**-\-extended-register**] [**-e** *expr*] [**-\-expression**=*expr*...] [**-f** *file*...] [**-\-file**=*file*...] [*file*...] # DESCRIPTION dc(1) is an arbitrary-precision calculator. It uses a stack (reverse Polish notation) to store numbers and results of computations. Arithmetic operations pop arguments off of the stack and push the results. If no files are given on the command-line, then dc(1) reads from **stdin** (see the **STDIN** section). Otherwise, those files are processed, and dc(1) will then exit. If a user wants to set up a standard environment, they can use **DC_ENV_ARGS** (see the **ENVIRONMENT VARIABLES** section). For example, if a user wants the **scale** always set to **10**, they can set **DC_ENV_ARGS** to **-e 10k**, and this dc(1) will always start with a **scale** of **10**. # OPTIONS The following are the options that dc(1) accepts. **-h**, **-\-help** : Prints a usage message and quits. **-v**, **-V**, **-\-version** : Print the version information (copyright header) and exit. **-i**, **-\-interactive** : Forces interactive mode. (See the **INTERACTIVE MODE** section.) This is a **non-portable extension**. **-L**, **-\-no-line-length** : Disables line length checking and prints numbers without backslashes and newlines. In other words, this option sets **BC_LINE_LENGTH** to **0** (see the **ENVIRONMENT VARIABLES** section). This is a **non-portable extension**. **-P**, **-\-no-prompt** : Disables the prompt in TTY mode. (The prompt is only enabled in TTY mode. See the **TTY MODE** section.) This is mostly for those users that do not want a prompt or are not used to having them in dc(1). Most of those users would want to put this option in **DC_ENV_ARGS**. These options override the **DC_PROMPT** and **DC_TTY_MODE** environment variables (see the **ENVIRONMENT VARIABLES** section). This is a **non-portable extension**. **-R**, **-\-no-read-prompt** : Disables the read prompt in TTY mode. (The read prompt is only enabled in TTY mode. See the **TTY MODE** section.) This is mostly for those users that do not want a read prompt or are not used to having them in dc(1). Most of those users would want to put this option in **BC_ENV_ARGS** (see the **ENVIRONMENT VARIABLES** section). This option is also useful in hash bang lines of dc(1) scripts that prompt for user input. This option does not disable the regular prompt because the read prompt is only used when the **?** command is used. These options *do* override the **DC_PROMPT** and **DC_TTY_MODE** environment variables (see the **ENVIRONMENT VARIABLES** section), but only for the read prompt. This is a **non-portable extension**. **-x** **-\-extended-register** : Enables extended register mode. See the *Extended Register Mode* subsection of the **REGISTERS** section for more information. This is a **non-portable extension**. **-z**, **-\-leading-zeroes** : Makes bc(1) print all numbers greater than **-1** and less than **1**, and not equal to **0**, with a leading zero. This can be set for individual numbers with the **plz(x)**, plznl(x)**, **pnlz(x)**, and **pnlznl(x)** functions in the extended math library (see the **LIBRARY** section). This is a **non-portable extension**. **-e** *expr*, **-\-expression**=*expr* : Evaluates *expr*. If multiple expressions are given, they are evaluated in order. If files are given as well (see below), the expressions and files are evaluated in the order given. This means that if a file is given before an expression, the file is read in and evaluated first. If this option is given on the command-line (i.e., not in **DC_ENV_ARGS**, see the **ENVIRONMENT VARIABLES** section), then after processing all expressions and files, dc(1) will exit, unless **-** (**stdin**) was given as an argument at least once to **-f** or **-\-file**, whether on the command-line or in **DC_ENV_ARGS**. However, if any other **-e**, **-\-expression**, **-f**, or **-\-file** arguments are given after **-f-** or equivalent is given, dc(1) will give a fatal error and exit. This is a **non-portable extension**. **-f** *file*, **-\-file**=*file* : Reads in *file* and evaluates it, line by line, as though it were read through **stdin**. If expressions are also given (see above), the expressions are evaluated in the order given. If this option is given on the command-line (i.e., not in **DC_ENV_ARGS**, see the **ENVIRONMENT VARIABLES** section), then after processing all expressions and files, dc(1) will exit, unless **-** (**stdin**) was given as an argument at least once to **-f** or **-\-file**. However, if any other **-e**, **-\-expression**, **-f**, or **-\-file** arguments are given after **-f-** or equivalent is given, dc(1) will give a fatal error and exit. This is a **non-portable extension**. All long options are **non-portable extensions**. # STDIN If no files are given on the command-line and no files or expressions are given by the **-f**, **-\-file**, **-e**, or **-\-expression** options, then dc(1) read from **stdin**. However, there is a caveat to this. First, **stdin** is evaluated a line at a time. The only exception to this is if a string has been finished, but not ended. This means that, except for escaped brackets, all brackets must be balanced before dc(1) parses and executes. # STDOUT Any non-error output is written to **stdout**. In addition, if history (see the **HISTORY** section) and the prompt (see the **TTY MODE** section) are enabled, both are output to **stdout**. **Note**: Unlike other dc(1) implementations, this dc(1) will issue a fatal error (see the **EXIT STATUS** section) if it cannot write to **stdout**, so if **stdout** is closed, as in **dc >&-**, it will quit with an error. This is done so that dc(1) can report problems when **stdout** is redirected to a file. If there are scripts that depend on the behavior of other dc(1) implementations, it is recommended that those scripts be changed to redirect **stdout** to **/dev/null**. # STDERR Any error output is written to **stderr**. **Note**: Unlike other dc(1) implementations, this dc(1) will issue a fatal error (see the **EXIT STATUS** section) if it cannot write to **stderr**, so if **stderr** is closed, as in **dc 2>&-**, it will quit with an error. This is done so that dc(1) can exit with an error code when **stderr** is redirected to a file. If there are scripts that depend on the behavior of other dc(1) implementations, it is recommended that those scripts be changed to redirect **stderr** to **/dev/null**. # SYNTAX Each item in the input source code, either a number (see the **NUMBERS** section) or a command (see the **COMMANDS** section), is processed and executed, in order. Input is processed immediately when entered. **ibase** is a register (see the **REGISTERS** section) that determines how to interpret constant numbers. It is the "input" base, or the number base used for interpreting input numbers. **ibase** is initially **10**. The max allowable value for **ibase** is **16**. The min allowable value for **ibase** is **2**. The max allowable value for **ibase** can be queried in dc(1) programs with the **T** command. **obase** is a register (see the **REGISTERS** section) that determines how to output results. It is the "output" base, or the number base used for outputting numbers. **obase** is initially **10**. The max allowable value for **obase** is **DC_BASE_MAX** and can be queried with the **U** command. The min allowable value for **obase** is **2**. Values are output in the specified base. The *scale* of an expression is the number of digits in the result of the expression right of the decimal point, and **scale** is a register (see the **REGISTERS** section) that sets the precision of any operations (with exceptions). **scale** is initially **0**. **scale** cannot be negative. The max allowable value for **scale** can be queried in dc(1) programs with the **V** command. ## Comments Comments go from **#** until, and not including, the next newline. This is a **non-portable extension**. # NUMBERS Numbers are strings made up of digits, uppercase letters up to **F**, and at most **1** period for a radix. Numbers can have up to **DC_NUM_MAX** digits. Uppercase letters are equal to **9** + their position in the alphabet (i.e., **A** equals **10**, or **9+1**). If a digit or letter makes no sense with the current value of **ibase**, they are set to the value of the highest valid digit in **ibase**. Single-character numbers (i.e., **A** alone) take the value that they would have if they were valid digits, regardless of the value of **ibase**. This means that **A** alone always equals decimal **10** and **F** alone always equals decimal **15**. # COMMANDS The valid commands are listed below. ## Printing These commands are used for printing. **p** : Prints the value on top of the stack, whether number or string, and prints a newline after. This does not alter the stack. **n** : Prints the value on top of the stack, whether number or string, and pops it off of the stack. **P** : Pops a value off the stack. If the value is a number, it is truncated and the absolute value of the result is printed as though **obase** is **256** and each digit is interpreted as an 8-bit ASCII character, making it a byte stream. If the value is a string, it is printed without a trailing newline. This is a **non-portable extension**. **f** : Prints the entire contents of the stack, in order from newest to oldest, without altering anything. Users should use this command when they get lost. ## Arithmetic These are the commands used for arithmetic. **+** : The top two values are popped off the stack, added, and the result is pushed onto the stack. The *scale* of the result is equal to the max *scale* of both operands. **-** : The top two values are popped off the stack, subtracted, and the result is pushed onto the stack. The *scale* of the result is equal to the max *scale* of both operands. **\*** : The top two values are popped off the stack, multiplied, and the result is pushed onto the stack. If **a** is the *scale* of the first expression and **b** is the *scale* of the second expression, the *scale* of the result is equal to **min(a+b,max(scale,a,b))** where **min()** and **max()** return the obvious values. **/** : The top two values are popped off the stack, divided, and the result is pushed onto the stack. The *scale* of the result is equal to **scale**. The first value popped off of the stack must be non-zero. **%** : The top two values are popped off the stack, remaindered, and the result is pushed onto the stack. Remaindering is equivalent to 1) Computing **a/b** to current **scale**, and 2) Using the result of step 1 to calculate **a-(a/b)\*b** to *scale* **max(scale+scale(b),scale(a))**. The first value popped off of the stack must be non-zero. **~** : The top two values are popped off the stack, divided and remaindered, and the results (divided first, remainder second) are pushed onto the stack. This is equivalent to **x y / x y %** except that **x** and **y** are only evaluated once. The first value popped off of the stack must be non-zero. This is a **non-portable extension**. **\^** : The top two values are popped off the stack, the second is raised to the power of the first, and the result is pushed onto the stack. The *scale* of the result is equal to **scale**. The first value popped off of the stack must be an integer, and if that value is negative, the second value popped off of the stack must be non-zero. **v** : The top value is popped off the stack, its square root is computed, and the result is pushed onto the stack. The *scale* of the result is equal to **scale**. The value popped off of the stack must be non-negative. **\_** : If this command *immediately* precedes a number (i.e., no spaces or other commands), then that number is input as a negative number. Otherwise, the top value on the stack is popped and copied, and the copy is negated and pushed onto the stack. This behavior without a number is a **non-portable extension**. **b** : The top value is popped off the stack, and if it is zero, it is pushed back onto the stack. Otherwise, its absolute value is pushed onto the stack. This is a **non-portable extension**. **|** : The top three values are popped off the stack, a modular exponentiation is computed, and the result is pushed onto the stack. The first value popped is used as the reduction modulus and must be an integer and non-zero. The second value popped is used as the exponent and must be an integer and non-negative. The third value popped is the base and must be an integer. This is a **non-portable extension**. **G** : The top two values are popped off of the stack, they are compared, and a **1** is pushed if they are equal, or **0** otherwise. This is a **non-portable extension**. **N** : The top value is popped off of the stack, and if it a **0**, a **1** is pushed; otherwise, a **0** is pushed. This is a **non-portable extension**. **(** : The top two values are popped off of the stack, they are compared, and a **1** is pushed if the first is less than the second, or **0** otherwise. This is a **non-portable extension**. **{** : The top two values are popped off of the stack, they are compared, and a **1** is pushed if the first is less than or equal to the second, or **0** otherwise. This is a **non-portable extension**. **)** : The top two values are popped off of the stack, they are compared, and a **1** is pushed if the first is greater than the second, or **0** otherwise. This is a **non-portable extension**. **}** : The top two values are popped off of the stack, they are compared, and a **1** is pushed if the first is greater than or equal to the second, or **0** otherwise. This is a **non-portable extension**. **M** : The top two values are popped off of the stack. If they are both non-zero, a **1** is pushed onto the stack. If either of them is zero, or both of them are, then a **0** is pushed onto the stack. This is like the **&&** operator in bc(1), and it is *not* a short-circuit operator. This is a **non-portable extension**. **m** : The top two values are popped off of the stack. If at least one of them is non-zero, a **1** is pushed onto the stack. If both of them are zero, then a **0** is pushed onto the stack. This is like the **||** operator in bc(1), and it is *not* a short-circuit operator. This is a **non-portable extension**. ## Stack Control These commands control the stack. **c** : Removes all items from ("clears") the stack. **d** : Copies the item on top of the stack ("duplicates") and pushes the copy onto the stack. **r** : Swaps ("reverses") the two top items on the stack. **R** : Pops ("removes") the top value from the stack. ## Register Control These commands control registers (see the **REGISTERS** section). **s**_r_ : Pops the value off the top of the stack and stores it into register *r*. **l**_r_ : Copies the value in register *r* and pushes it onto the stack. This does not alter the contents of *r*. **S**_r_ : Pops the value off the top of the (main) stack and pushes it onto the stack of register *r*. The previous value of the register becomes inaccessible. **L**_r_ : Pops the value off the top of the stack for register *r* and push it onto the main stack. The previous value in the stack for register *r*, if any, is now accessible via the **l**_r_ command. ## Parameters These commands control the values of **ibase**, **obase**, and **scale**. Also see the **SYNTAX** section. **i** : Pops the value off of the top of the stack and uses it to set **ibase**, which must be between **2** and **16**, inclusive. If the value on top of the stack has any *scale*, the *scale* is ignored. **o** : Pops the value off of the top of the stack and uses it to set **obase**, which must be between **2** and **DC_BASE_MAX**, inclusive (see the **LIMITS** section). If the value on top of the stack has any *scale*, the *scale* is ignored. **k** : Pops the value off of the top of the stack and uses it to set **scale**, which must be non-negative. If the value on top of the stack has any *scale*, the *scale* is ignored. **I** : Pushes the current value of **ibase** onto the main stack. **O** : Pushes the current value of **obase** onto the main stack. **K** : Pushes the current value of **scale** onto the main stack. **T** : Pushes the maximum allowable value of **ibase** onto the main stack. This is a **non-portable extension**. **U** : Pushes the maximum allowable value of **obase** onto the main stack. This is a **non-portable extension**. **V** : Pushes the maximum allowable value of **scale** onto the main stack. This is a **non-portable extension**. ## Strings The following commands control strings. dc(1) can work with both numbers and strings, and registers (see the **REGISTERS** section) can hold both strings and numbers. dc(1) always knows whether the contents of a register are a string or a number. While arithmetic operations have to have numbers, and will print an error if given a string, other commands accept strings. Strings can also be executed as macros. For example, if the string **[1pR]** is executed as a macro, then the code **1pR** is executed, meaning that the **1** will be printed with a newline after and then popped from the stack. **\[**_characters_**\]** : Makes a string containing *characters* and pushes it onto the stack. If there are brackets (**\[** and **\]**) in the string, then they must be balanced. Unbalanced brackets can be escaped using a backslash (**\\**) character. If there is a backslash character in the string, the character after it (even another backslash) is put into the string verbatim, but the (first) backslash is not. **a** : The value on top of the stack is popped. If it is a number, it is truncated and its absolute value is taken. The result mod **256** is calculated. If that result is **0**, push an empty string; otherwise, push a one-character string where the character is the result of the mod interpreted as an ASCII character. If it is a string, then a new string is made. If the original string is empty, the new string is empty. If it is not, then the first character of the original string is used to create the new string as a one-character string. The new string is then pushed onto the stack. This is a **non-portable extension**. **x** : Pops a value off of the top of the stack. If it is a number, it is pushed back onto the stack. If it is a string, it is executed as a macro. This behavior is the norm whenever a macro is executed, whether by this command or by the conditional execution commands below. **\>**_r_ : Pops two values off of the stack that must be numbers and compares them. If the first value is greater than the second, then the contents of register *r* are executed. For example, **0 1>a** will execute the contents of register **a**, and **1 0>a** will not. If either or both of the values are not numbers, dc(1) will raise an error and reset (see the **RESET** section). **>**_r_**e**_s_ : Like the above, but will execute register *s* if the comparison fails. If either or both of the values are not numbers, dc(1) will raise an error and reset (see the **RESET** section). This is a **non-portable extension**. **!\>**_r_ : Pops two values off of the stack that must be numbers and compares them. If the first value is not greater than the second (less than or equal to), then the contents of register *r* are executed. If either or both of the values are not numbers, dc(1) will raise an error and reset (see the **RESET** section). **!\>**_r_**e**_s_ : Like the above, but will execute register *s* if the comparison fails. If either or both of the values are not numbers, dc(1) will raise an error and reset (see the **RESET** section). This is a **non-portable extension**. **\<**_r_ : Pops two values off of the stack that must be numbers and compares them. If the first value is less than the second, then the contents of register *r* are executed. If either or both of the values are not numbers, dc(1) will raise an error and reset (see the **RESET** section). **\<**_r_**e**_s_ : Like the above, but will execute register *s* if the comparison fails. If either or both of the values are not numbers, dc(1) will raise an error and reset (see the **RESET** section). This is a **non-portable extension**. **!\<**_r_ : Pops two values off of the stack that must be numbers and compares them. If the first value is not less than the second (greater than or equal to), then the contents of register *r* are executed. If either or both of the values are not numbers, dc(1) will raise an error and reset (see the **RESET** section). **!\<**_r_**e**_s_ : Like the above, but will execute register *s* if the comparison fails. If either or both of the values are not numbers, dc(1) will raise an error and reset (see the **RESET** section). This is a **non-portable extension**. **=**_r_ : Pops two values off of the stack that must be numbers and compares them. If the first value is equal to the second, then the contents of register *r* are executed. If either or both of the values are not numbers, dc(1) will raise an error and reset (see the **RESET** section). **=**_r_**e**_s_ : Like the above, but will execute register *s* if the comparison fails. If either or both of the values are not numbers, dc(1) will raise an error and reset (see the **RESET** section). This is a **non-portable extension**. **!=**_r_ : Pops two values off of the stack that must be numbers and compares them. If the first value is not equal to the second, then the contents of register *r* are executed. If either or both of the values are not numbers, dc(1) will raise an error and reset (see the **RESET** section). **!=**_r_**e**_s_ : Like the above, but will execute register *s* if the comparison fails. If either or both of the values are not numbers, dc(1) will raise an error and reset (see the **RESET** section). This is a **non-portable extension**. **?** : Reads a line from the **stdin** and executes it. This is to allow macros to request input from users. **q** : During execution of a macro, this exits the execution of that macro and the execution of the macro that executed it. If there are no macros, or only one macro executing, dc(1) exits. **Q** : Pops a value from the stack which must be non-negative and is used the number of macro executions to pop off of the execution stack. If the number of levels to pop is greater than the number of executing macros, dc(1) exits. **,** : Pushes the depth of the execution stack onto the stack. The execution stack is the stack of string executions. The number that is pushed onto the stack is exactly as many as is needed to make dc(1) exit with the **Q** command, so the sequence **,Q** will make dc(1) exit. ## Status These commands query status of the stack or its top value. **Z** : Pops a value off of the stack. If it is a number, calculates the number of significant decimal digits it has and pushes the result. It will push **1** if the argument is **0** with no decimal places. If it is a string, pushes the number of characters the string has. **X** : Pops a value off of the stack. If it is a number, pushes the *scale* of the value onto the stack. If it is a string, pushes **0**. **z** : Pushes the current depth of the stack (before execution of this command) onto the stack. **y**_r_ : Pushes the current stack depth of the register *r* onto the main stack. Because each register has a depth of **1** (with the value **0** in the top item) when dc(1) starts, dc(1) requires that each register's stack must always have at least one item; dc(1) will give an error and reset otherwise (see the **RESET** section). This means that this command will never push **0**. This is a **non-portable extension**. ## Arrays These commands manipulate arrays. **:**_r_ : Pops the top two values off of the stack. The second value will be stored in the array *r* (see the **REGISTERS** section), indexed by the first value. **;**_r_ : Pops the value on top of the stack and uses it as an index into the array *r*. The selected value is then pushed onto the stack. **Y**_r_ : Pushes the length of the array *r* onto the stack. This is a **non-portable extension**. ## Global Settings These commands retrieve global settings. These are the only commands that require multiple specific characters, and all of them begin with the letter **g**. Only the characters below are allowed after the character **g**; any other character produces a parse error (see the **ERRORS** section). **gl** : Pushes the line length set by **DC_LINE_LENGTH** (see the **ENVIRONMENT VARIABLES** section) onto the stack. **gz** : Pushes **0** onto the stack if the leading zero setting has not been enabled with the **-z** or **-\-leading-zeroes** options (see the **OPTIONS** section), non-zero otherwise. # REGISTERS Registers are names that can store strings, numbers, and arrays. (Number/string registers do not interfere with array registers.) Each register is also its own stack, so the current register value is the top of the stack for the register. All registers, when first referenced, have one value (**0**) in their stack, and it is a runtime error to attempt to pop that item off of the register stack. In non-extended register mode, a register name is just the single character that follows any command that needs a register name. The only exceptions are: a newline (**'\\n'**) and a left bracket (**'['**); it is a parse error for a newline or a left bracket to be used as a register name. ## Extended Register Mode Unlike most other dc(1) implentations, this dc(1) provides nearly unlimited amounts of registers, if extended register mode is enabled. If extended register mode is enabled (**-x** or **-\-extended-register** command-line arguments are given), then normal single character registers are used *unless* the character immediately following a command that needs a register name is a space (according to **isspace()**) and not a newline (**'\\n'**). In that case, the register name is found according to the regex **\[a-z\]\[a-z0-9\_\]\*** (like bc(1) identifiers), and it is a parse error if the next non-space characters do not match that regex. # RESET When dc(1) encounters an error or a signal that it has a non-default handler for, it resets. This means that several things happen. First, any macros that are executing are stopped and popped off the stack. The behavior is not unlike that of exceptions in programming languages. Then the execution point is set so that any code waiting to execute (after all macros returned) is skipped. Thus, when dc(1) resets, it skips any remaining code waiting to be executed. Then, if it is interactive mode, and the error was not a fatal error (see the **EXIT STATUS** section), it asks for more input; otherwise, it exits with the appropriate return code. # PERFORMANCE Most dc(1) implementations use **char** types to calculate the value of **1** decimal digit at a time, but that can be slow. This dc(1) does something different. It uses large integers to calculate more than **1** decimal digit at a time. If built in a environment where **DC_LONG_BIT** (see the **LIMITS** section) is **64**, then each integer has **9** decimal digits. If built in an environment where **DC_LONG_BIT** is **32** then each integer has **4** decimal digits. This value (the number of decimal digits per large integer) is called **DC_BASE_DIGS**. In addition, this dc(1) uses an even larger integer for overflow checking. This integer type depends on the value of **DC_LONG_BIT**, but is always at least twice as large as the integer type used to store digits. # LIMITS The following are the limits on dc(1): **DC_LONG_BIT** : The number of bits in the **long** type in the environment where dc(1) was built. This determines how many decimal digits can be stored in a single large integer (see the **PERFORMANCE** section). **DC_BASE_DIGS** : The number of decimal digits per large integer (see the **PERFORMANCE** section). Depends on **DC_LONG_BIT**. **DC_BASE_POW** : The max decimal number that each large integer can store (see **DC_BASE_DIGS**) plus **1**. Depends on **DC_BASE_DIGS**. **DC_OVERFLOW_MAX** : The max number that the overflow type (see the **PERFORMANCE** section) can hold. Depends on **DC_LONG_BIT**. **DC_BASE_MAX** : The maximum output base. Set at **DC_BASE_POW**. **DC_DIM_MAX** : The maximum size of arrays. Set at **SIZE_MAX-1**. **DC_SCALE_MAX** : The maximum **scale**. Set at **DC_OVERFLOW_MAX-1**. **DC_STRING_MAX** : The maximum length of strings. Set at **DC_OVERFLOW_MAX-1**. **DC_NAME_MAX** : The maximum length of identifiers. Set at **DC_OVERFLOW_MAX-1**. **DC_NUM_MAX** : The maximum length of a number (in decimal digits), which includes digits after the decimal point. Set at **DC_OVERFLOW_MAX-1**. Exponent : The maximum allowable exponent (positive or negative). Set at **DC_OVERFLOW_MAX**. Number of vars : The maximum number of vars/arrays. Set at **SIZE_MAX-1**. These limits are meant to be effectively non-existent; the limits are so large (at least on 64-bit machines) that there should not be any point at which they become a problem. In fact, memory should be exhausted before these limits should be hit. # ENVIRONMENT VARIABLES dc(1) recognizes the following environment variables: **DC_ENV_ARGS** : This is another way to give command-line arguments to dc(1). They should be in the same format as all other command-line arguments. These are always processed first, so any files given in **DC_ENV_ARGS** will be processed before arguments and files given on the command-line. This gives the user the ability to set up "standard" options and files to be used at every invocation. The most useful thing for such files to contain would be useful functions that the user might want every time dc(1) runs. Another use would be to use the **-e** option to set **scale** to a value other than **0**. The code that parses **DC_ENV_ARGS** will correctly handle quoted arguments, but it does not understand escape sequences. For example, the string **"/home/gavin/some dc file.dc"** will be correctly parsed, but the string **"/home/gavin/some \"dc\" file.dc"** will include the backslashes. The quote parsing will handle either kind of quotes, **'** or **"**. Thus, if you have a file with any number of single quotes in the name, you can use double quotes as the outside quotes, as in **"some 'dc' file.dc"**, and vice versa if you have a file with double quotes. However, handling a file with both kinds of quotes in **DC_ENV_ARGS** is not supported due to the complexity of the parsing, though such files are still supported on the command-line where the parsing is done by the shell. **DC_LINE_LENGTH** : If this environment variable exists and contains an integer that is greater than **1** and is less than **UINT16_MAX** (**2\^16-1**), dc(1) will output lines to that length, including the backslash newline combo. The default line length is **70**. The special value of **0** will disable line length checking and print numbers without regard to line length and without backslashes and newlines. **DC_SIGINT_RESET** : If dc(1) is not in interactive mode (see the **INTERACTIVE MODE** section), then this environment variable has no effect because dc(1) exits on **SIGINT** when not in interactive mode. However, when dc(1) is in interactive mode, then if this environment variable exists and contains an integer, a non-zero value makes dc(1) reset on **SIGINT**, rather than exit, and zero makes dc(1) exit. If this environment variable exists and is *not* an integer, then dc(1) will exit on **SIGINT**. This environment variable overrides the default, which can be queried with the **-h** or **-\-help** options. **DC_TTY_MODE** : If TTY mode is *not* available (see the **TTY MODE** section), then this environment variable has no effect. However, when TTY mode is available, then if this environment variable exists and contains an integer, then a non-zero value makes dc(1) use TTY mode, and zero makes dc(1) not use TTY mode. This environment variable overrides the default, which can be queried with the **-h** or **-\-help** options. **DC_PROMPT** : If TTY mode is *not* available (see the **TTY MODE** section), then this environment variable has no effect. However, when TTY mode is available, then if this environment variable exists and contains an integer, a non-zero value makes dc(1) use a prompt, and zero or a non-integer makes dc(1) not use a prompt. If this environment variable does not exist and **DC_TTY_MODE** does, then the value of the **DC_TTY_MODE** environment variable is used. This environment variable and the **DC_TTY_MODE** environment variable override the default, which can be queried with the **-h** or **-\-help** options. +**DC_EXPR_EXIT** + +: If any expressions or expression files are given on the command-line with + **-e**, **-\-expression**, **-f**, or **-\-file**, then if this environment + variable exists and contains an integer, a non-zero value makes dc(1) exit + after executing the expressions and expression files, and a non-zero value + makes dc(1) not exit. + + This environment variable overrides the default, which can be queried with + the **-h** or **-\-help** options. + # EXIT STATUS dc(1) returns the following exit statuses: **0** : No error. **1** : A math error occurred. This follows standard practice of using **1** for expected errors, since math errors will happen in the process of normal execution. Math errors include divide by **0**, taking the square root of a negative number, attempting to convert a negative number to a hardware integer, overflow when converting a number to a hardware integer, overflow when calculating the size of a number, and attempting to use a non-integer where an integer is required. Converting to a hardware integer happens for the second operand of the power (**\^**) operator. **2** : A parse error occurred. Parse errors include unexpected **EOF**, using an invalid character, failing to find the end of a string or comment, and using a token where it is invalid. **3** : A runtime error occurred. Runtime errors include assigning an invalid number to any global (**ibase**, **obase**, or **scale**), giving a bad expression to a **read()** call, calling **read()** inside of a **read()** call, type errors (including attempting to execute a number), and attempting an operation when the stack has too few elements. **4** : A fatal error occurred. Fatal errors include memory allocation errors, I/O errors, failing to open files, attempting to use files that do not have only ASCII characters (dc(1) only accepts ASCII characters), attempting to open a directory as a file, and giving invalid command-line options. The exit status **4** is special; when a fatal error occurs, dc(1) always exits and returns **4**, no matter what mode dc(1) is in. The other statuses will only be returned when dc(1) is not in interactive mode (see the **INTERACTIVE MODE** section), since dc(1) resets its state (see the **RESET** section) and accepts more input when one of those errors occurs in interactive mode. This is also the case when interactive mode is forced by the **-i** flag or **-\-interactive** option. These exit statuses allow dc(1) to be used in shell scripting with error checking, and its normal behavior can be forced by using the **-i** flag or **-\-interactive** option. # INTERACTIVE MODE Like bc(1), dc(1) has an interactive mode and a non-interactive mode. Interactive mode is turned on automatically when both **stdin** and **stdout** are hooked to a terminal, but the **-i** flag and **-\-interactive** option can turn it on in other situations. In interactive mode, dc(1) attempts to recover from errors (see the **RESET** section), and in normal execution, flushes **stdout** as soon as execution is done for the current input. dc(1) may also reset on **SIGINT** instead of exit, depending on the contents of, or default for, the **DC_SIGINT_RESET** environment variable (see the **ENVIRONMENT VARIABLES** section). # TTY MODE If **stdin**, **stdout**, and **stderr** are all connected to a TTY, then "TTY mode" is considered to be available, and thus, dc(1) can turn on TTY mode, subject to some settings. If there is the environment variable **DC_TTY_MODE** in the environment (see the **ENVIRONMENT VARIABLES** section), then if that environment variable contains a non-zero integer, dc(1) will turn on TTY mode when **stdin**, **stdout**, and **stderr** are all connected to a TTY. If the **DC_TTY_MODE** environment variable exists but is *not* a non-zero integer, then dc(1) will not turn TTY mode on. If the environment variable **DC_TTY_MODE** does *not* exist, the default setting is used. The default setting can be queried with the **-h** or **-\-help** options. TTY mode is different from interactive mode because interactive mode is required in the [bc(1) specification][1], and interactive mode requires only **stdin** and **stdout** to be connected to a terminal. ## Prompt If TTY mode is available, then a prompt can be enabled. Like TTY mode itself, it can be turned on or off with an environment variable: **DC_PROMPT** (see the **ENVIRONMENT VARIABLES** section). If the environment variable **DC_PROMPT** exists and is a non-zero integer, then the prompt is turned on when **stdin**, **stdout**, and **stderr** are connected to a TTY and the **-P** and **-\-no-prompt** options were not used. The read prompt will be turned on under the same conditions, except that the **-R** and **-\-no-read-prompt** options must also not be used. However, if **DC_PROMPT** does not exist, the prompt can be enabled or disabled with the **DC_TTY_MODE** environment variable, the **-P** and **-\-no-prompt** options, and the **-R** and **-\-no-read-prompt** options. See the **ENVIRONMENT VARIABLES** and **OPTIONS** sections for more details. # SIGNAL HANDLING Sending a **SIGINT** will cause dc(1) to do one of two things. If dc(1) is not in interactive mode (see the **INTERACTIVE MODE** section), or the **DC_SIGINT_RESET** environment variable (see the **ENVIRONMENT VARIABLES** section), or its default, is either not an integer or it is zero, dc(1) will exit. However, if dc(1) is in interactive mode, and the **DC_SIGINT_RESET** or its default is an integer and non-zero, then dc(1) will stop executing the current input and reset (see the **RESET** section) upon receiving a **SIGINT**. Note that "current input" can mean one of two things. If dc(1) is processing input from **stdin** in interactive mode, it will ask for more input. If dc(1) is processing input from a file in interactive mode, it will stop processing the file and start processing the next file, if one exists, or ask for input from **stdin** if no other file exists. This means that if a **SIGINT** is sent to dc(1) as it is executing a file, it can seem as though dc(1) did not respond to the signal since it will immediately start executing the next file. This is by design; most files that users execute when interacting with dc(1) have function definitions, which are quick to parse. If a file takes a long time to execute, there may be a bug in that file. The rest of the files could still be executed without problem, allowing the user to continue. **SIGTERM** and **SIGQUIT** cause dc(1) to clean up and exit, and it uses the default handler for all other signals. # LOCALES This dc(1) ships with support for adding error messages for different locales and thus, supports **LC_MESSAGES**. # SEE ALSO bc(1) # STANDARDS The dc(1) utility operators are compliant with the operators in the bc(1) [IEEE Std 1003.1-2017 (“POSIX.1-2017”)][1] specification. # BUGS None are known. Report bugs at https://git.yzena.com/gavin/bc. # AUTHOR Gavin D. Howard and contributors. [1]: https://pubs.opengroup.org/onlinepubs/9699919799/utilities/bc.html diff --git a/contrib/bc/manuals/dc/EHN.1 b/contrib/bc/manuals/dc/EHN.1 index 1124d907bdd9..223bd9f08dfa 100644 --- a/contrib/bc/manuals/dc/EHN.1 +++ b/contrib/bc/manuals/dc/EHN.1 @@ -1,1312 +1,1325 @@ .\" .\" SPDX-License-Identifier: BSD-2-Clause .\" .\" Copyright (c) 2018-2021 Gavin D. Howard and contributors. .\" .\" Redistribution and use in source and binary forms, with or without .\" modification, are permitted provided that the following conditions are met: .\" .\" * Redistributions of source code must retain the above copyright notice, .\" this list of conditions and the following disclaimer. .\" .\" * Redistributions in binary form must reproduce the above copyright notice, .\" this list of conditions and the following disclaimer in the documentation .\" and/or other materials provided with the distribution. .\" .\" THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" .\" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE .\" IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE .\" ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE .\" LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR .\" CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF .\" SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS .\" INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN .\" CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) .\" ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE .\" POSSIBILITY OF SUCH DAMAGE. .\" .TH "DC" "1" "June 2021" "Gavin D. Howard" "General Commands Manual" .SH Name .PP dc - arbitrary-precision decimal reverse-Polish notation calculator .SH SYNOPSIS .PP \f[B]dc\f[R] [\f[B]-hiPRvVx\f[R]] [\f[B]--version\f[R]] [\f[B]--help\f[R]] [\f[B]--interactive\f[R]] [\f[B]--no-prompt\f[R]] [\f[B]--no-read-prompt\f[R]] [\f[B]--extended-register\f[R]] [\f[B]-e\f[R] \f[I]expr\f[R]] [\f[B]--expression\f[R]=\f[I]expr\f[R]\&...] [\f[B]-f\f[R] \f[I]file\f[R]\&...] [\f[B]--file\f[R]=\f[I]file\f[R]\&...] [\f[I]file\f[R]\&...] .SH DESCRIPTION .PP dc(1) is an arbitrary-precision calculator. It uses a stack (reverse Polish notation) to store numbers and results of computations. Arithmetic operations pop arguments off of the stack and push the results. .PP If no files are given on the command-line, then dc(1) reads from \f[B]stdin\f[R] (see the \f[B]STDIN\f[R] section). Otherwise, those files are processed, and dc(1) will then exit. .PP If a user wants to set up a standard environment, they can use \f[B]DC_ENV_ARGS\f[R] (see the \f[B]ENVIRONMENT VARIABLES\f[R] section). For example, if a user wants the \f[B]scale\f[R] always set to \f[B]10\f[R], they can set \f[B]DC_ENV_ARGS\f[R] to \f[B]-e 10k\f[R], and this dc(1) will always start with a \f[B]scale\f[R] of \f[B]10\f[R]. .SH OPTIONS .PP The following are the options that dc(1) accepts. .TP \f[B]-h\f[R], \f[B]--help\f[R] Prints a usage message and quits. .TP \f[B]-v\f[R], \f[B]-V\f[R], \f[B]--version\f[R] Print the version information (copyright header) and exit. .TP \f[B]-i\f[R], \f[B]--interactive\f[R] Forces interactive mode. (See the \f[B]INTERACTIVE MODE\f[R] section.) .RS .PP This is a \f[B]non-portable extension\f[R]. .RE .TP \f[B]-L\f[R], \f[B]--no-line-length\f[R] Disables line length checking and prints numbers without backslashes and newlines. In other words, this option sets \f[B]BC_LINE_LENGTH\f[R] to \f[B]0\f[R] (see the \f[B]ENVIRONMENT VARIABLES\f[R] section). .RS .PP This is a \f[B]non-portable extension\f[R]. .RE .TP \f[B]-P\f[R], \f[B]--no-prompt\f[R] Disables the prompt in TTY mode. (The prompt is only enabled in TTY mode. See the \f[B]TTY MODE\f[R] section.) This is mostly for those users that do not want a prompt or are not used to having them in dc(1). Most of those users would want to put this option in \f[B]DC_ENV_ARGS\f[R]. .RS .PP These options override the \f[B]DC_PROMPT\f[R] and \f[B]DC_TTY_MODE\f[R] environment variables (see the \f[B]ENVIRONMENT VARIABLES\f[R] section). .PP This is a \f[B]non-portable extension\f[R]. .RE .TP \f[B]-R\f[R], \f[B]--no-read-prompt\f[R] Disables the read prompt in TTY mode. (The read prompt is only enabled in TTY mode. See the \f[B]TTY MODE\f[R] section.) This is mostly for those users that do not want a read prompt or are not used to having them in dc(1). Most of those users would want to put this option in \f[B]BC_ENV_ARGS\f[R] (see the \f[B]ENVIRONMENT VARIABLES\f[R] section). This option is also useful in hash bang lines of dc(1) scripts that prompt for user input. .RS .PP This option does not disable the regular prompt because the read prompt is only used when the \f[B]?\f[R] command is used. .PP These options \f[I]do\f[R] override the \f[B]DC_PROMPT\f[R] and \f[B]DC_TTY_MODE\f[R] environment variables (see the \f[B]ENVIRONMENT VARIABLES\f[R] section), but only for the read prompt. .PP This is a \f[B]non-portable extension\f[R]. .RE .TP \f[B]-x\f[R] \f[B]--extended-register\f[R] Enables extended register mode. See the \f[I]Extended Register Mode\f[R] subsection of the \f[B]REGISTERS\f[R] section for more information. .RS .PP This is a \f[B]non-portable extension\f[R]. .RE .TP \f[B]-z\f[R], \f[B]--leading-zeroes\f[R] Makes bc(1) print all numbers greater than \f[B]-1\f[R] and less than \f[B]1\f[R], and not equal to \f[B]0\f[R], with a leading zero. .RS .PP This can be set for individual numbers with the \f[B]plz(x)\f[R], plznl(x)**, \f[B]pnlz(x)\f[R], and \f[B]pnlznl(x)\f[R] functions in the extended math library (see the \f[B]LIBRARY\f[R] section). .PP This is a \f[B]non-portable extension\f[R]. .RE .TP \f[B]-e\f[R] \f[I]expr\f[R], \f[B]--expression\f[R]=\f[I]expr\f[R] Evaluates \f[I]expr\f[R]. If multiple expressions are given, they are evaluated in order. If files are given as well (see below), the expressions and files are evaluated in the order given. This means that if a file is given before an expression, the file is read in and evaluated first. .RS .PP If this option is given on the command-line (i.e., not in \f[B]DC_ENV_ARGS\f[R], see the \f[B]ENVIRONMENT VARIABLES\f[R] section), then after processing all expressions and files, dc(1) will exit, unless \f[B]-\f[R] (\f[B]stdin\f[R]) was given as an argument at least once to \f[B]-f\f[R] or \f[B]--file\f[R], whether on the command-line or in \f[B]DC_ENV_ARGS\f[R]. However, if any other \f[B]-e\f[R], \f[B]--expression\f[R], \f[B]-f\f[R], or \f[B]--file\f[R] arguments are given after \f[B]-f-\f[R] or equivalent is given, dc(1) will give a fatal error and exit. .PP This is a \f[B]non-portable extension\f[R]. .RE .TP \f[B]-f\f[R] \f[I]file\f[R], \f[B]--file\f[R]=\f[I]file\f[R] Reads in \f[I]file\f[R] and evaluates it, line by line, as though it were read through \f[B]stdin\f[R]. If expressions are also given (see above), the expressions are evaluated in the order given. .RS .PP If this option is given on the command-line (i.e., not in \f[B]DC_ENV_ARGS\f[R], see the \f[B]ENVIRONMENT VARIABLES\f[R] section), then after processing all expressions and files, dc(1) will exit, unless \f[B]-\f[R] (\f[B]stdin\f[R]) was given as an argument at least once to \f[B]-f\f[R] or \f[B]--file\f[R]. However, if any other \f[B]-e\f[R], \f[B]--expression\f[R], \f[B]-f\f[R], or \f[B]--file\f[R] arguments are given after \f[B]-f-\f[R] or equivalent is given, dc(1) will give a fatal error and exit. .PP This is a \f[B]non-portable extension\f[R]. .RE .PP All long options are \f[B]non-portable extensions\f[R]. .SH STDIN .PP If no files are given on the command-line and no files or expressions are given by the \f[B]-f\f[R], \f[B]--file\f[R], \f[B]-e\f[R], or \f[B]--expression\f[R] options, then dc(1) read from \f[B]stdin\f[R]. .PP However, there is a caveat to this. .PP First, \f[B]stdin\f[R] is evaluated a line at a time. The only exception to this is if a string has been finished, but not ended. This means that, except for escaped brackets, all brackets must be balanced before dc(1) parses and executes. .SH STDOUT .PP Any non-error output is written to \f[B]stdout\f[R]. In addition, if history (see the \f[B]HISTORY\f[R] section) and the prompt (see the \f[B]TTY MODE\f[R] section) are enabled, both are output to \f[B]stdout\f[R]. .PP \f[B]Note\f[R]: Unlike other dc(1) implementations, this dc(1) will issue a fatal error (see the \f[B]EXIT STATUS\f[R] section) if it cannot write to \f[B]stdout\f[R], so if \f[B]stdout\f[R] is closed, as in \f[B]dc >&-\f[R], it will quit with an error. This is done so that dc(1) can report problems when \f[B]stdout\f[R] is redirected to a file. .PP If there are scripts that depend on the behavior of other dc(1) implementations, it is recommended that those scripts be changed to redirect \f[B]stdout\f[R] to \f[B]/dev/null\f[R]. .SH STDERR .PP Any error output is written to \f[B]stderr\f[R]. .PP \f[B]Note\f[R]: Unlike other dc(1) implementations, this dc(1) will issue a fatal error (see the \f[B]EXIT STATUS\f[R] section) if it cannot write to \f[B]stderr\f[R], so if \f[B]stderr\f[R] is closed, as in \f[B]dc 2>&-\f[R], it will quit with an error. This is done so that dc(1) can exit with an error code when \f[B]stderr\f[R] is redirected to a file. .PP If there are scripts that depend on the behavior of other dc(1) implementations, it is recommended that those scripts be changed to redirect \f[B]stderr\f[R] to \f[B]/dev/null\f[R]. .SH SYNTAX .PP Each item in the input source code, either a number (see the \f[B]NUMBERS\f[R] section) or a command (see the \f[B]COMMANDS\f[R] section), is processed and executed, in order. Input is processed immediately when entered. .PP \f[B]ibase\f[R] is a register (see the \f[B]REGISTERS\f[R] section) that determines how to interpret constant numbers. It is the \[lq]input\[rq] base, or the number base used for interpreting input numbers. \f[B]ibase\f[R] is initially \f[B]10\f[R]. The max allowable value for \f[B]ibase\f[R] is \f[B]16\f[R]. The min allowable value for \f[B]ibase\f[R] is \f[B]2\f[R]. The max allowable value for \f[B]ibase\f[R] can be queried in dc(1) programs with the \f[B]T\f[R] command. .PP \f[B]obase\f[R] is a register (see the \f[B]REGISTERS\f[R] section) that determines how to output results. It is the \[lq]output\[rq] base, or the number base used for outputting numbers. \f[B]obase\f[R] is initially \f[B]10\f[R]. The max allowable value for \f[B]obase\f[R] is \f[B]DC_BASE_MAX\f[R] and can be queried with the \f[B]U\f[R] command. The min allowable value for \f[B]obase\f[R] is \f[B]2\f[R]. Values are output in the specified base. .PP The \f[I]scale\f[R] of an expression is the number of digits in the result of the expression right of the decimal point, and \f[B]scale\f[R] is a register (see the \f[B]REGISTERS\f[R] section) that sets the precision of any operations (with exceptions). \f[B]scale\f[R] is initially \f[B]0\f[R]. \f[B]scale\f[R] cannot be negative. The max allowable value for \f[B]scale\f[R] can be queried in dc(1) programs with the \f[B]V\f[R] command. .SS Comments .PP Comments go from \f[B]#\f[R] until, and not including, the next newline. This is a \f[B]non-portable extension\f[R]. .SH NUMBERS .PP Numbers are strings made up of digits, uppercase letters up to \f[B]F\f[R], and at most \f[B]1\f[R] period for a radix. Numbers can have up to \f[B]DC_NUM_MAX\f[R] digits. Uppercase letters are equal to \f[B]9\f[R] + their position in the alphabet (i.e., \f[B]A\f[R] equals \f[B]10\f[R], or \f[B]9+1\f[R]). If a digit or letter makes no sense with the current value of \f[B]ibase\f[R], they are set to the value of the highest valid digit in \f[B]ibase\f[R]. .PP Single-character numbers (i.e., \f[B]A\f[R] alone) take the value that they would have if they were valid digits, regardless of the value of \f[B]ibase\f[R]. This means that \f[B]A\f[R] alone always equals decimal \f[B]10\f[R] and \f[B]F\f[R] alone always equals decimal \f[B]15\f[R]. .SH COMMANDS .PP The valid commands are listed below. .SS Printing .PP These commands are used for printing. .TP \f[B]p\f[R] Prints the value on top of the stack, whether number or string, and prints a newline after. .RS .PP This does not alter the stack. .RE .TP \f[B]n\f[R] Prints the value on top of the stack, whether number or string, and pops it off of the stack. .TP \f[B]P\f[R] Pops a value off the stack. .RS .PP If the value is a number, it is truncated and the absolute value of the result is printed as though \f[B]obase\f[R] is \f[B]256\f[R] and each digit is interpreted as an 8-bit ASCII character, making it a byte stream. .PP If the value is a string, it is printed without a trailing newline. .PP This is a \f[B]non-portable extension\f[R]. .RE .TP \f[B]f\f[R] Prints the entire contents of the stack, in order from newest to oldest, without altering anything. .RS .PP Users should use this command when they get lost. .RE .SS Arithmetic .PP These are the commands used for arithmetic. .TP \f[B]+\f[R] The top two values are popped off the stack, added, and the result is pushed onto the stack. The \f[I]scale\f[R] of the result is equal to the max \f[I]scale\f[R] of both operands. .TP \f[B]-\f[R] The top two values are popped off the stack, subtracted, and the result is pushed onto the stack. The \f[I]scale\f[R] of the result is equal to the max \f[I]scale\f[R] of both operands. .TP \f[B]*\f[R] The top two values are popped off the stack, multiplied, and the result is pushed onto the stack. If \f[B]a\f[R] is the \f[I]scale\f[R] of the first expression and \f[B]b\f[R] is the \f[I]scale\f[R] of the second expression, the \f[I]scale\f[R] of the result is equal to \f[B]min(a+b,max(scale,a,b))\f[R] where \f[B]min()\f[R] and \f[B]max()\f[R] return the obvious values. .TP \f[B]/\f[R] The top two values are popped off the stack, divided, and the result is pushed onto the stack. The \f[I]scale\f[R] of the result is equal to \f[B]scale\f[R]. .RS .PP The first value popped off of the stack must be non-zero. .RE .TP \f[B]%\f[R] The top two values are popped off the stack, remaindered, and the result is pushed onto the stack. .RS .PP Remaindering is equivalent to 1) Computing \f[B]a/b\f[R] to current \f[B]scale\f[R], and 2) Using the result of step 1 to calculate \f[B]a-(a/b)*b\f[R] to \f[I]scale\f[R] \f[B]max(scale+scale(b),scale(a))\f[R]. .PP The first value popped off of the stack must be non-zero. .RE .TP \f[B]\[ti]\f[R] The top two values are popped off the stack, divided and remaindered, and the results (divided first, remainder second) are pushed onto the stack. This is equivalent to \f[B]x y / x y %\f[R] except that \f[B]x\f[R] and \f[B]y\f[R] are only evaluated once. .RS .PP The first value popped off of the stack must be non-zero. .PP This is a \f[B]non-portable extension\f[R]. .RE .TP \f[B]\[ha]\f[R] The top two values are popped off the stack, the second is raised to the power of the first, and the result is pushed onto the stack. The \f[I]scale\f[R] of the result is equal to \f[B]scale\f[R]. .RS .PP The first value popped off of the stack must be an integer, and if that value is negative, the second value popped off of the stack must be non-zero. .RE .TP \f[B]v\f[R] The top value is popped off the stack, its square root is computed, and the result is pushed onto the stack. The \f[I]scale\f[R] of the result is equal to \f[B]scale\f[R]. .RS .PP The value popped off of the stack must be non-negative. .RE .TP \f[B]_\f[R] If this command \f[I]immediately\f[R] precedes a number (i.e., no spaces or other commands), then that number is input as a negative number. .RS .PP Otherwise, the top value on the stack is popped and copied, and the copy is negated and pushed onto the stack. This behavior without a number is a \f[B]non-portable extension\f[R]. .RE .TP \f[B]b\f[R] The top value is popped off the stack, and if it is zero, it is pushed back onto the stack. Otherwise, its absolute value is pushed onto the stack. .RS .PP This is a \f[B]non-portable extension\f[R]. .RE .TP \f[B]|\f[R] The top three values are popped off the stack, a modular exponentiation is computed, and the result is pushed onto the stack. .RS .PP The first value popped is used as the reduction modulus and must be an integer and non-zero. The second value popped is used as the exponent and must be an integer and non-negative. The third value popped is the base and must be an integer. .PP This is a \f[B]non-portable extension\f[R]. .RE .TP \f[B]G\f[R] The top two values are popped off of the stack, they are compared, and a \f[B]1\f[R] is pushed if they are equal, or \f[B]0\f[R] otherwise. .RS .PP This is a \f[B]non-portable extension\f[R]. .RE .TP \f[B]N\f[R] The top value is popped off of the stack, and if it a \f[B]0\f[R], a \f[B]1\f[R] is pushed; otherwise, a \f[B]0\f[R] is pushed. .RS .PP This is a \f[B]non-portable extension\f[R]. .RE .TP \f[B](\f[R] The top two values are popped off of the stack, they are compared, and a \f[B]1\f[R] is pushed if the first is less than the second, or \f[B]0\f[R] otherwise. .RS .PP This is a \f[B]non-portable extension\f[R]. .RE .TP \f[B]{\f[R] The top two values are popped off of the stack, they are compared, and a \f[B]1\f[R] is pushed if the first is less than or equal to the second, or \f[B]0\f[R] otherwise. .RS .PP This is a \f[B]non-portable extension\f[R]. .RE .TP \f[B])\f[R] The top two values are popped off of the stack, they are compared, and a \f[B]1\f[R] is pushed if the first is greater than the second, or \f[B]0\f[R] otherwise. .RS .PP This is a \f[B]non-portable extension\f[R]. .RE .TP \f[B]}\f[R] The top two values are popped off of the stack, they are compared, and a \f[B]1\f[R] is pushed if the first is greater than or equal to the second, or \f[B]0\f[R] otherwise. .RS .PP This is a \f[B]non-portable extension\f[R]. .RE .TP \f[B]M\f[R] The top two values are popped off of the stack. If they are both non-zero, a \f[B]1\f[R] is pushed onto the stack. If either of them is zero, or both of them are, then a \f[B]0\f[R] is pushed onto the stack. .RS .PP This is like the \f[B]&&\f[R] operator in bc(1), and it is \f[I]not\f[R] a short-circuit operator. .PP This is a \f[B]non-portable extension\f[R]. .RE .TP \f[B]m\f[R] The top two values are popped off of the stack. If at least one of them is non-zero, a \f[B]1\f[R] is pushed onto the stack. If both of them are zero, then a \f[B]0\f[R] is pushed onto the stack. .RS .PP This is like the \f[B]||\f[R] operator in bc(1), and it is \f[I]not\f[R] a short-circuit operator. .PP This is a \f[B]non-portable extension\f[R]. .RE .SS Stack Control .PP These commands control the stack. .TP \f[B]c\f[R] Removes all items from (\[lq]clears\[rq]) the stack. .TP \f[B]d\f[R] Copies the item on top of the stack (\[lq]duplicates\[rq]) and pushes the copy onto the stack. .TP \f[B]r\f[R] Swaps (\[lq]reverses\[rq]) the two top items on the stack. .TP \f[B]R\f[R] Pops (\[lq]removes\[rq]) the top value from the stack. .SS Register Control .PP These commands control registers (see the \f[B]REGISTERS\f[R] section). .TP \f[B]s\f[R]\f[I]r\f[R] Pops the value off the top of the stack and stores it into register \f[I]r\f[R]. .TP \f[B]l\f[R]\f[I]r\f[R] Copies the value in register \f[I]r\f[R] and pushes it onto the stack. This does not alter the contents of \f[I]r\f[R]. .TP \f[B]S\f[R]\f[I]r\f[R] Pops the value off the top of the (main) stack and pushes it onto the stack of register \f[I]r\f[R]. The previous value of the register becomes inaccessible. .TP \f[B]L\f[R]\f[I]r\f[R] Pops the value off the top of the stack for register \f[I]r\f[R] and push it onto the main stack. The previous value in the stack for register \f[I]r\f[R], if any, is now accessible via the \f[B]l\f[R]\f[I]r\f[R] command. .SS Parameters .PP These commands control the values of \f[B]ibase\f[R], \f[B]obase\f[R], and \f[B]scale\f[R]. Also see the \f[B]SYNTAX\f[R] section. .TP \f[B]i\f[R] Pops the value off of the top of the stack and uses it to set \f[B]ibase\f[R], which must be between \f[B]2\f[R] and \f[B]16\f[R], inclusive. .RS .PP If the value on top of the stack has any \f[I]scale\f[R], the \f[I]scale\f[R] is ignored. .RE .TP \f[B]o\f[R] Pops the value off of the top of the stack and uses it to set \f[B]obase\f[R], which must be between \f[B]2\f[R] and \f[B]DC_BASE_MAX\f[R], inclusive (see the \f[B]LIMITS\f[R] section). .RS .PP If the value on top of the stack has any \f[I]scale\f[R], the \f[I]scale\f[R] is ignored. .RE .TP \f[B]k\f[R] Pops the value off of the top of the stack and uses it to set \f[B]scale\f[R], which must be non-negative. .RS .PP If the value on top of the stack has any \f[I]scale\f[R], the \f[I]scale\f[R] is ignored. .RE .TP \f[B]I\f[R] Pushes the current value of \f[B]ibase\f[R] onto the main stack. .TP \f[B]O\f[R] Pushes the current value of \f[B]obase\f[R] onto the main stack. .TP \f[B]K\f[R] Pushes the current value of \f[B]scale\f[R] onto the main stack. .TP \f[B]T\f[R] Pushes the maximum allowable value of \f[B]ibase\f[R] onto the main stack. .RS .PP This is a \f[B]non-portable extension\f[R]. .RE .TP \f[B]U\f[R] Pushes the maximum allowable value of \f[B]obase\f[R] onto the main stack. .RS .PP This is a \f[B]non-portable extension\f[R]. .RE .TP \f[B]V\f[R] Pushes the maximum allowable value of \f[B]scale\f[R] onto the main stack. .RS .PP This is a \f[B]non-portable extension\f[R]. .RE .SS Strings .PP The following commands control strings. .PP dc(1) can work with both numbers and strings, and registers (see the \f[B]REGISTERS\f[R] section) can hold both strings and numbers. dc(1) always knows whether the contents of a register are a string or a number. .PP While arithmetic operations have to have numbers, and will print an error if given a string, other commands accept strings. .PP Strings can also be executed as macros. For example, if the string \f[B][1pR]\f[R] is executed as a macro, then the code \f[B]1pR\f[R] is executed, meaning that the \f[B]1\f[R] will be printed with a newline after and then popped from the stack. .TP \f[B][\f[R]\f[I]characters\f[R]\f[B]]\f[R] Makes a string containing \f[I]characters\f[R] and pushes it onto the stack. .RS .PP If there are brackets (\f[B][\f[R] and \f[B]]\f[R]) in the string, then they must be balanced. Unbalanced brackets can be escaped using a backslash (\f[B]\[rs]\f[R]) character. .PP If there is a backslash character in the string, the character after it (even another backslash) is put into the string verbatim, but the (first) backslash is not. .RE .TP \f[B]a\f[R] The value on top of the stack is popped. .RS .PP If it is a number, it is truncated and its absolute value is taken. The result mod \f[B]256\f[R] is calculated. If that result is \f[B]0\f[R], push an empty string; otherwise, push a one-character string where the character is the result of the mod interpreted as an ASCII character. .PP If it is a string, then a new string is made. If the original string is empty, the new string is empty. If it is not, then the first character of the original string is used to create the new string as a one-character string. The new string is then pushed onto the stack. .PP This is a \f[B]non-portable extension\f[R]. .RE .TP \f[B]x\f[R] Pops a value off of the top of the stack. .RS .PP If it is a number, it is pushed back onto the stack. .PP If it is a string, it is executed as a macro. .PP This behavior is the norm whenever a macro is executed, whether by this command or by the conditional execution commands below. .RE .TP \f[B]>\f[R]\f[I]r\f[R] Pops two values off of the stack that must be numbers and compares them. If the first value is greater than the second, then the contents of register \f[I]r\f[R] are executed. .RS .PP For example, \f[B]0 1>a\f[R] will execute the contents of register \f[B]a\f[R], and \f[B]1 0>a\f[R] will not. .PP If either or both of the values are not numbers, dc(1) will raise an error and reset (see the \f[B]RESET\f[R] section). .RE .TP \f[B]>\f[R]\f[I]r\f[R]\f[B]e\f[R]\f[I]s\f[R] Like the above, but will execute register \f[I]s\f[R] if the comparison fails. .RS .PP If either or both of the values are not numbers, dc(1) will raise an error and reset (see the \f[B]RESET\f[R] section). .PP This is a \f[B]non-portable extension\f[R]. .RE .TP \f[B]!>\f[R]\f[I]r\f[R] Pops two values off of the stack that must be numbers and compares them. If the first value is not greater than the second (less than or equal to), then the contents of register \f[I]r\f[R] are executed. .RS .PP If either or both of the values are not numbers, dc(1) will raise an error and reset (see the \f[B]RESET\f[R] section). .RE .TP \f[B]!>\f[R]\f[I]r\f[R]\f[B]e\f[R]\f[I]s\f[R] Like the above, but will execute register \f[I]s\f[R] if the comparison fails. .RS .PP If either or both of the values are not numbers, dc(1) will raise an error and reset (see the \f[B]RESET\f[R] section). .PP This is a \f[B]non-portable extension\f[R]. .RE .TP \f[B]<\f[R]\f[I]r\f[R] Pops two values off of the stack that must be numbers and compares them. If the first value is less than the second, then the contents of register \f[I]r\f[R] are executed. .RS .PP If either or both of the values are not numbers, dc(1) will raise an error and reset (see the \f[B]RESET\f[R] section). .RE .TP \f[B]<\f[R]\f[I]r\f[R]\f[B]e\f[R]\f[I]s\f[R] Like the above, but will execute register \f[I]s\f[R] if the comparison fails. .RS .PP If either or both of the values are not numbers, dc(1) will raise an error and reset (see the \f[B]RESET\f[R] section). .PP This is a \f[B]non-portable extension\f[R]. .RE .TP \f[B]!<\f[R]\f[I]r\f[R] Pops two values off of the stack that must be numbers and compares them. If the first value is not less than the second (greater than or equal to), then the contents of register \f[I]r\f[R] are executed. .RS .PP If either or both of the values are not numbers, dc(1) will raise an error and reset (see the \f[B]RESET\f[R] section). .RE .TP \f[B]!<\f[R]\f[I]r\f[R]\f[B]e\f[R]\f[I]s\f[R] Like the above, but will execute register \f[I]s\f[R] if the comparison fails. .RS .PP If either or both of the values are not numbers, dc(1) will raise an error and reset (see the \f[B]RESET\f[R] section). .PP This is a \f[B]non-portable extension\f[R]. .RE .TP \f[B]=\f[R]\f[I]r\f[R] Pops two values off of the stack that must be numbers and compares them. If the first value is equal to the second, then the contents of register \f[I]r\f[R] are executed. .RS .PP If either or both of the values are not numbers, dc(1) will raise an error and reset (see the \f[B]RESET\f[R] section). .RE .TP \f[B]=\f[R]\f[I]r\f[R]\f[B]e\f[R]\f[I]s\f[R] Like the above, but will execute register \f[I]s\f[R] if the comparison fails. .RS .PP If either or both of the values are not numbers, dc(1) will raise an error and reset (see the \f[B]RESET\f[R] section). .PP This is a \f[B]non-portable extension\f[R]. .RE .TP \f[B]!=\f[R]\f[I]r\f[R] Pops two values off of the stack that must be numbers and compares them. If the first value is not equal to the second, then the contents of register \f[I]r\f[R] are executed. .RS .PP If either or both of the values are not numbers, dc(1) will raise an error and reset (see the \f[B]RESET\f[R] section). .RE .TP \f[B]!=\f[R]\f[I]r\f[R]\f[B]e\f[R]\f[I]s\f[R] Like the above, but will execute register \f[I]s\f[R] if the comparison fails. .RS .PP If either or both of the values are not numbers, dc(1) will raise an error and reset (see the \f[B]RESET\f[R] section). .PP This is a \f[B]non-portable extension\f[R]. .RE .TP \f[B]?\f[R] Reads a line from the \f[B]stdin\f[R] and executes it. This is to allow macros to request input from users. .TP \f[B]q\f[R] During execution of a macro, this exits the execution of that macro and the execution of the macro that executed it. If there are no macros, or only one macro executing, dc(1) exits. .TP \f[B]Q\f[R] Pops a value from the stack which must be non-negative and is used the number of macro executions to pop off of the execution stack. If the number of levels to pop is greater than the number of executing macros, dc(1) exits. .TP \f[B],\f[R] Pushes the depth of the execution stack onto the stack. The execution stack is the stack of string executions. The number that is pushed onto the stack is exactly as many as is needed to make dc(1) exit with the \f[B]Q\f[R] command, so the sequence \f[B],Q\f[R] will make dc(1) exit. .SS Status .PP These commands query status of the stack or its top value. .TP \f[B]Z\f[R] Pops a value off of the stack. .RS .PP If it is a number, calculates the number of significant decimal digits it has and pushes the result. It will push \f[B]1\f[R] if the argument is \f[B]0\f[R] with no decimal places. .PP If it is a string, pushes the number of characters the string has. .RE .TP \f[B]X\f[R] Pops a value off of the stack. .RS .PP If it is a number, pushes the \f[I]scale\f[R] of the value onto the stack. .PP If it is a string, pushes \f[B]0\f[R]. .RE .TP \f[B]z\f[R] Pushes the current depth of the stack (before execution of this command) onto the stack. .TP \f[B]y\f[R]\f[I]r\f[R] Pushes the current stack depth of the register \f[I]r\f[R] onto the main stack. .RS .PP Because each register has a depth of \f[B]1\f[R] (with the value \f[B]0\f[R] in the top item) when dc(1) starts, dc(1) requires that each register\[cq]s stack must always have at least one item; dc(1) will give an error and reset otherwise (see the \f[B]RESET\f[R] section). This means that this command will never push \f[B]0\f[R]. .PP This is a \f[B]non-portable extension\f[R]. .RE .SS Arrays .PP These commands manipulate arrays. .TP \f[B]:\f[R]\f[I]r\f[R] Pops the top two values off of the stack. The second value will be stored in the array \f[I]r\f[R] (see the \f[B]REGISTERS\f[R] section), indexed by the first value. .TP \f[B];\f[R]\f[I]r\f[R] Pops the value on top of the stack and uses it as an index into the array \f[I]r\f[R]. The selected value is then pushed onto the stack. .TP \f[B]Y\f[R]\f[I]r\f[R] Pushes the length of the array \f[I]r\f[R] onto the stack. .RS .PP This is a \f[B]non-portable extension\f[R]. .RE .SS Global Settings .PP These commands retrieve global settings. These are the only commands that require multiple specific characters, and all of them begin with the letter \f[B]g\f[R]. Only the characters below are allowed after the character \f[B]g\f[R]; any other character produces a parse error (see the \f[B]ERRORS\f[R] section). .TP \f[B]gl\f[R] Pushes the line length set by \f[B]DC_LINE_LENGTH\f[R] (see the \f[B]ENVIRONMENT VARIABLES\f[R] section) onto the stack. .TP \f[B]gz\f[R] Pushes \f[B]0\f[R] onto the stack if the leading zero setting has not been enabled with the \f[B]-z\f[R] or \f[B]--leading-zeroes\f[R] options (see the \f[B]OPTIONS\f[R] section), non-zero otherwise. .SH REGISTERS .PP Registers are names that can store strings, numbers, and arrays. (Number/string registers do not interfere with array registers.) .PP Each register is also its own stack, so the current register value is the top of the stack for the register. All registers, when first referenced, have one value (\f[B]0\f[R]) in their stack, and it is a runtime error to attempt to pop that item off of the register stack. .PP In non-extended register mode, a register name is just the single character that follows any command that needs a register name. The only exceptions are: a newline (\f[B]`\[rs]n'\f[R]) and a left bracket (\f[B]`['\f[R]); it is a parse error for a newline or a left bracket to be used as a register name. .SS Extended Register Mode .PP Unlike most other dc(1) implentations, this dc(1) provides nearly unlimited amounts of registers, if extended register mode is enabled. .PP If extended register mode is enabled (\f[B]-x\f[R] or \f[B]--extended-register\f[R] command-line arguments are given), then normal single character registers are used \f[I]unless\f[R] the character immediately following a command that needs a register name is a space (according to \f[B]isspace()\f[R]) and not a newline (\f[B]`\[rs]n'\f[R]). .PP In that case, the register name is found according to the regex \f[B][a-z][a-z0-9_]*\f[R] (like bc(1) identifiers), and it is a parse error if the next non-space characters do not match that regex. .SH RESET .PP When dc(1) encounters an error or a signal that it has a non-default handler for, it resets. This means that several things happen. .PP First, any macros that are executing are stopped and popped off the stack. The behavior is not unlike that of exceptions in programming languages. Then the execution point is set so that any code waiting to execute (after all macros returned) is skipped. .PP Thus, when dc(1) resets, it skips any remaining code waiting to be executed. Then, if it is interactive mode, and the error was not a fatal error (see the \f[B]EXIT STATUS\f[R] section), it asks for more input; otherwise, it exits with the appropriate return code. .SH PERFORMANCE .PP Most dc(1) implementations use \f[B]char\f[R] types to calculate the value of \f[B]1\f[R] decimal digit at a time, but that can be slow. This dc(1) does something different. .PP It uses large integers to calculate more than \f[B]1\f[R] decimal digit at a time. If built in a environment where \f[B]DC_LONG_BIT\f[R] (see the \f[B]LIMITS\f[R] section) is \f[B]64\f[R], then each integer has \f[B]9\f[R] decimal digits. If built in an environment where \f[B]DC_LONG_BIT\f[R] is \f[B]32\f[R] then each integer has \f[B]4\f[R] decimal digits. This value (the number of decimal digits per large integer) is called \f[B]DC_BASE_DIGS\f[R]. .PP In addition, this dc(1) uses an even larger integer for overflow checking. This integer type depends on the value of \f[B]DC_LONG_BIT\f[R], but is always at least twice as large as the integer type used to store digits. .SH LIMITS .PP The following are the limits on dc(1): .TP \f[B]DC_LONG_BIT\f[R] The number of bits in the \f[B]long\f[R] type in the environment where dc(1) was built. This determines how many decimal digits can be stored in a single large integer (see the \f[B]PERFORMANCE\f[R] section). .TP \f[B]DC_BASE_DIGS\f[R] The number of decimal digits per large integer (see the \f[B]PERFORMANCE\f[R] section). Depends on \f[B]DC_LONG_BIT\f[R]. .TP \f[B]DC_BASE_POW\f[R] The max decimal number that each large integer can store (see \f[B]DC_BASE_DIGS\f[R]) plus \f[B]1\f[R]. Depends on \f[B]DC_BASE_DIGS\f[R]. .TP \f[B]DC_OVERFLOW_MAX\f[R] The max number that the overflow type (see the \f[B]PERFORMANCE\f[R] section) can hold. Depends on \f[B]DC_LONG_BIT\f[R]. .TP \f[B]DC_BASE_MAX\f[R] The maximum output base. Set at \f[B]DC_BASE_POW\f[R]. .TP \f[B]DC_DIM_MAX\f[R] The maximum size of arrays. Set at \f[B]SIZE_MAX-1\f[R]. .TP \f[B]DC_SCALE_MAX\f[R] The maximum \f[B]scale\f[R]. Set at \f[B]DC_OVERFLOW_MAX-1\f[R]. .TP \f[B]DC_STRING_MAX\f[R] The maximum length of strings. Set at \f[B]DC_OVERFLOW_MAX-1\f[R]. .TP \f[B]DC_NAME_MAX\f[R] The maximum length of identifiers. Set at \f[B]DC_OVERFLOW_MAX-1\f[R]. .TP \f[B]DC_NUM_MAX\f[R] The maximum length of a number (in decimal digits), which includes digits after the decimal point. Set at \f[B]DC_OVERFLOW_MAX-1\f[R]. .TP Exponent The maximum allowable exponent (positive or negative). Set at \f[B]DC_OVERFLOW_MAX\f[R]. .TP Number of vars The maximum number of vars/arrays. Set at \f[B]SIZE_MAX-1\f[R]. .PP These limits are meant to be effectively non-existent; the limits are so large (at least on 64-bit machines) that there should not be any point at which they become a problem. In fact, memory should be exhausted before these limits should be hit. .SH ENVIRONMENT VARIABLES .PP dc(1) recognizes the following environment variables: .TP \f[B]DC_ENV_ARGS\f[R] This is another way to give command-line arguments to dc(1). They should be in the same format as all other command-line arguments. These are always processed first, so any files given in \f[B]DC_ENV_ARGS\f[R] will be processed before arguments and files given on the command-line. This gives the user the ability to set up \[lq]standard\[rq] options and files to be used at every invocation. The most useful thing for such files to contain would be useful functions that the user might want every time dc(1) runs. Another use would be to use the \f[B]-e\f[R] option to set \f[B]scale\f[R] to a value other than \f[B]0\f[R]. .RS .PP The code that parses \f[B]DC_ENV_ARGS\f[R] will correctly handle quoted arguments, but it does not understand escape sequences. For example, the string \f[B]\[lq]/home/gavin/some dc file.dc\[rq]\f[R] will be correctly parsed, but the string \f[B]\[lq]/home/gavin/some \[dq]dc\[dq] file.dc\[rq]\f[R] will include the backslashes. .PP The quote parsing will handle either kind of quotes, \f[B]\[cq]\f[R] or \f[B]\[lq]\f[R]. Thus, if you have a file with any number of single quotes in the name, you can use double quotes as the outside quotes, as in \f[B]\[lq]some `dc' file.dc\[rq]\f[R], and vice versa if you have a file with double quotes. However, handling a file with both kinds of quotes in \f[B]DC_ENV_ARGS\f[R] is not supported due to the complexity of the parsing, though such files are still supported on the command-line where the parsing is done by the shell. .RE .TP \f[B]DC_LINE_LENGTH\f[R] If this environment variable exists and contains an integer that is greater than \f[B]1\f[R] and is less than \f[B]UINT16_MAX\f[R] (\f[B]2\[ha]16-1\f[R]), dc(1) will output lines to that length, including the backslash newline combo. The default line length is \f[B]70\f[R]. .RS .PP The special value of \f[B]0\f[R] will disable line length checking and print numbers without regard to line length and without backslashes and newlines. .RE .TP \f[B]DC_SIGINT_RESET\f[R] If dc(1) is not in interactive mode (see the \f[B]INTERACTIVE MODE\f[R] section), then this environment variable has no effect because dc(1) exits on \f[B]SIGINT\f[R] when not in interactive mode. .RS .PP However, when dc(1) is in interactive mode, then if this environment variable exists and contains an integer, a non-zero value makes dc(1) reset on \f[B]SIGINT\f[R], rather than exit, and zero makes dc(1) exit. If this environment variable exists and is \f[I]not\f[R] an integer, then dc(1) will exit on \f[B]SIGINT\f[R]. .PP This environment variable overrides the default, which can be queried with the \f[B]-h\f[R] or \f[B]--help\f[R] options. .RE .TP \f[B]DC_TTY_MODE\f[R] If TTY mode is \f[I]not\f[R] available (see the \f[B]TTY MODE\f[R] section), then this environment variable has no effect. .RS .PP However, when TTY mode is available, then if this environment variable exists and contains an integer, then a non-zero value makes dc(1) use TTY mode, and zero makes dc(1) not use TTY mode. .PP This environment variable overrides the default, which can be queried with the \f[B]-h\f[R] or \f[B]--help\f[R] options. .RE .TP \f[B]DC_PROMPT\f[R] If TTY mode is \f[I]not\f[R] available (see the \f[B]TTY MODE\f[R] section), then this environment variable has no effect. .RS .PP However, when TTY mode is available, then if this environment variable exists and contains an integer, a non-zero value makes dc(1) use a prompt, and zero or a non-integer makes dc(1) not use a prompt. If this environment variable does not exist and \f[B]DC_TTY_MODE\f[R] does, then the value of the \f[B]DC_TTY_MODE\f[R] environment variable is used. .PP This environment variable and the \f[B]DC_TTY_MODE\f[R] environment variable override the default, which can be queried with the \f[B]-h\f[R] or \f[B]--help\f[R] options. .RE +.TP +\f[B]DC_EXPR_EXIT\f[R] +If any expressions or expression files are given on the command-line +with \f[B]-e\f[R], \f[B]--expression\f[R], \f[B]-f\f[R], or +\f[B]--file\f[R], then if this environment variable exists and contains +an integer, a non-zero value makes dc(1) exit after executing the +expressions and expression files, and a non-zero value makes dc(1) not +exit. +.RS +.PP +This environment variable overrides the default, which can be queried +with the \f[B]-h\f[R] or \f[B]--help\f[R] options. +.RE .SH EXIT STATUS .PP dc(1) returns the following exit statuses: .TP \f[B]0\f[R] No error. .TP \f[B]1\f[R] A math error occurred. This follows standard practice of using \f[B]1\f[R] for expected errors, since math errors will happen in the process of normal execution. .RS .PP Math errors include divide by \f[B]0\f[R], taking the square root of a negative number, attempting to convert a negative number to a hardware integer, overflow when converting a number to a hardware integer, overflow when calculating the size of a number, and attempting to use a non-integer where an integer is required. .PP Converting to a hardware integer happens for the second operand of the power (\f[B]\[ha]\f[R]) operator. .RE .TP \f[B]2\f[R] A parse error occurred. .RS .PP Parse errors include unexpected \f[B]EOF\f[R], using an invalid character, failing to find the end of a string or comment, and using a token where it is invalid. .RE .TP \f[B]3\f[R] A runtime error occurred. .RS .PP Runtime errors include assigning an invalid number to any global (\f[B]ibase\f[R], \f[B]obase\f[R], or \f[B]scale\f[R]), giving a bad expression to a \f[B]read()\f[R] call, calling \f[B]read()\f[R] inside of a \f[B]read()\f[R] call, type errors (including attempting to execute a number), and attempting an operation when the stack has too few elements. .RE .TP \f[B]4\f[R] A fatal error occurred. .RS .PP Fatal errors include memory allocation errors, I/O errors, failing to open files, attempting to use files that do not have only ASCII characters (dc(1) only accepts ASCII characters), attempting to open a directory as a file, and giving invalid command-line options. .RE .PP The exit status \f[B]4\f[R] is special; when a fatal error occurs, dc(1) always exits and returns \f[B]4\f[R], no matter what mode dc(1) is in. .PP The other statuses will only be returned when dc(1) is not in interactive mode (see the \f[B]INTERACTIVE MODE\f[R] section), since dc(1) resets its state (see the \f[B]RESET\f[R] section) and accepts more input when one of those errors occurs in interactive mode. This is also the case when interactive mode is forced by the \f[B]-i\f[R] flag or \f[B]--interactive\f[R] option. .PP These exit statuses allow dc(1) to be used in shell scripting with error checking, and its normal behavior can be forced by using the \f[B]-i\f[R] flag or \f[B]--interactive\f[R] option. .SH INTERACTIVE MODE .PP Like bc(1), dc(1) has an interactive mode and a non-interactive mode. Interactive mode is turned on automatically when both \f[B]stdin\f[R] and \f[B]stdout\f[R] are hooked to a terminal, but the \f[B]-i\f[R] flag and \f[B]--interactive\f[R] option can turn it on in other situations. .PP In interactive mode, dc(1) attempts to recover from errors (see the \f[B]RESET\f[R] section), and in normal execution, flushes \f[B]stdout\f[R] as soon as execution is done for the current input. dc(1) may also reset on \f[B]SIGINT\f[R] instead of exit, depending on the contents of, or default for, the \f[B]DC_SIGINT_RESET\f[R] environment variable (see the \f[B]ENVIRONMENT VARIABLES\f[R] section). .SH TTY MODE .PP If \f[B]stdin\f[R], \f[B]stdout\f[R], and \f[B]stderr\f[R] are all connected to a TTY, then \[lq]TTY mode\[rq] is considered to be available, and thus, dc(1) can turn on TTY mode, subject to some settings. .PP If there is the environment variable \f[B]DC_TTY_MODE\f[R] in the environment (see the \f[B]ENVIRONMENT VARIABLES\f[R] section), then if that environment variable contains a non-zero integer, dc(1) will turn on TTY mode when \f[B]stdin\f[R], \f[B]stdout\f[R], and \f[B]stderr\f[R] are all connected to a TTY. If the \f[B]DC_TTY_MODE\f[R] environment variable exists but is \f[I]not\f[R] a non-zero integer, then dc(1) will not turn TTY mode on. .PP If the environment variable \f[B]DC_TTY_MODE\f[R] does \f[I]not\f[R] exist, the default setting is used. The default setting can be queried with the \f[B]-h\f[R] or \f[B]--help\f[R] options. .PP TTY mode is different from interactive mode because interactive mode is required in the bc(1) specification (https://pubs.opengroup.org/onlinepubs/9699919799/utilities/bc.html), and interactive mode requires only \f[B]stdin\f[R] and \f[B]stdout\f[R] to be connected to a terminal. .SS Prompt .PP If TTY mode is available, then a prompt can be enabled. Like TTY mode itself, it can be turned on or off with an environment variable: \f[B]DC_PROMPT\f[R] (see the \f[B]ENVIRONMENT VARIABLES\f[R] section). .PP If the environment variable \f[B]DC_PROMPT\f[R] exists and is a non-zero integer, then the prompt is turned on when \f[B]stdin\f[R], \f[B]stdout\f[R], and \f[B]stderr\f[R] are connected to a TTY and the \f[B]-P\f[R] and \f[B]--no-prompt\f[R] options were not used. The read prompt will be turned on under the same conditions, except that the \f[B]-R\f[R] and \f[B]--no-read-prompt\f[R] options must also not be used. .PP However, if \f[B]DC_PROMPT\f[R] does not exist, the prompt can be enabled or disabled with the \f[B]DC_TTY_MODE\f[R] environment variable, the \f[B]-P\f[R] and \f[B]--no-prompt\f[R] options, and the \f[B]-R\f[R] and \f[B]--no-read-prompt\f[R] options. See the \f[B]ENVIRONMENT VARIABLES\f[R] and \f[B]OPTIONS\f[R] sections for more details. .SH SIGNAL HANDLING .PP Sending a \f[B]SIGINT\f[R] will cause dc(1) to do one of two things. .PP If dc(1) is not in interactive mode (see the \f[B]INTERACTIVE MODE\f[R] section), or the \f[B]DC_SIGINT_RESET\f[R] environment variable (see the \f[B]ENVIRONMENT VARIABLES\f[R] section), or its default, is either not an integer or it is zero, dc(1) will exit. .PP However, if dc(1) is in interactive mode, and the \f[B]DC_SIGINT_RESET\f[R] or its default is an integer and non-zero, then dc(1) will stop executing the current input and reset (see the \f[B]RESET\f[R] section) upon receiving a \f[B]SIGINT\f[R]. .PP Note that \[lq]current input\[rq] can mean one of two things. If dc(1) is processing input from \f[B]stdin\f[R] in interactive mode, it will ask for more input. If dc(1) is processing input from a file in interactive mode, it will stop processing the file and start processing the next file, if one exists, or ask for input from \f[B]stdin\f[R] if no other file exists. .PP This means that if a \f[B]SIGINT\f[R] is sent to dc(1) as it is executing a file, it can seem as though dc(1) did not respond to the signal since it will immediately start executing the next file. This is by design; most files that users execute when interacting with dc(1) have function definitions, which are quick to parse. If a file takes a long time to execute, there may be a bug in that file. The rest of the files could still be executed without problem, allowing the user to continue. .PP \f[B]SIGTERM\f[R] and \f[B]SIGQUIT\f[R] cause dc(1) to clean up and exit, and it uses the default handler for all other signals. .SH SEE ALSO .PP bc(1) .SH STANDARDS .PP The dc(1) utility operators are compliant with the operators in the bc(1) IEEE Std 1003.1-2017 (\[lq]POSIX.1-2017\[rq]) (https://pubs.opengroup.org/onlinepubs/9699919799/utilities/bc.html) specification. .SH BUGS .PP None are known. Report bugs at https://git.yzena.com/gavin/bc. .SH AUTHOR .PP Gavin D. Howard and contributors. diff --git a/contrib/bc/manuals/dc/EHN.1.md b/contrib/bc/manuals/dc/EHN.1.md index 50cb37ef2586..56ac39ed599e 100644 --- a/contrib/bc/manuals/dc/EHN.1.md +++ b/contrib/bc/manuals/dc/EHN.1.md @@ -1,1189 +1,1200 @@ # Name dc - arbitrary-precision decimal reverse-Polish notation calculator # SYNOPSIS **dc** [**-hiPRvVx**] [**-\-version**] [**-\-help**] [**-\-interactive**] [**-\-no-prompt**] [**-\-no-read-prompt**] [**-\-extended-register**] [**-e** *expr*] [**-\-expression**=*expr*...] [**-f** *file*...] [**-\-file**=*file*...] [*file*...] # DESCRIPTION dc(1) is an arbitrary-precision calculator. It uses a stack (reverse Polish notation) to store numbers and results of computations. Arithmetic operations pop arguments off of the stack and push the results. If no files are given on the command-line, then dc(1) reads from **stdin** (see the **STDIN** section). Otherwise, those files are processed, and dc(1) will then exit. If a user wants to set up a standard environment, they can use **DC_ENV_ARGS** (see the **ENVIRONMENT VARIABLES** section). For example, if a user wants the **scale** always set to **10**, they can set **DC_ENV_ARGS** to **-e 10k**, and this dc(1) will always start with a **scale** of **10**. # OPTIONS The following are the options that dc(1) accepts. **-h**, **-\-help** : Prints a usage message and quits. **-v**, **-V**, **-\-version** : Print the version information (copyright header) and exit. **-i**, **-\-interactive** : Forces interactive mode. (See the **INTERACTIVE MODE** section.) This is a **non-portable extension**. **-L**, **-\-no-line-length** : Disables line length checking and prints numbers without backslashes and newlines. In other words, this option sets **BC_LINE_LENGTH** to **0** (see the **ENVIRONMENT VARIABLES** section). This is a **non-portable extension**. **-P**, **-\-no-prompt** : Disables the prompt in TTY mode. (The prompt is only enabled in TTY mode. See the **TTY MODE** section.) This is mostly for those users that do not want a prompt or are not used to having them in dc(1). Most of those users would want to put this option in **DC_ENV_ARGS**. These options override the **DC_PROMPT** and **DC_TTY_MODE** environment variables (see the **ENVIRONMENT VARIABLES** section). This is a **non-portable extension**. **-R**, **-\-no-read-prompt** : Disables the read prompt in TTY mode. (The read prompt is only enabled in TTY mode. See the **TTY MODE** section.) This is mostly for those users that do not want a read prompt or are not used to having them in dc(1). Most of those users would want to put this option in **BC_ENV_ARGS** (see the **ENVIRONMENT VARIABLES** section). This option is also useful in hash bang lines of dc(1) scripts that prompt for user input. This option does not disable the regular prompt because the read prompt is only used when the **?** command is used. These options *do* override the **DC_PROMPT** and **DC_TTY_MODE** environment variables (see the **ENVIRONMENT VARIABLES** section), but only for the read prompt. This is a **non-portable extension**. **-x** **-\-extended-register** : Enables extended register mode. See the *Extended Register Mode* subsection of the **REGISTERS** section for more information. This is a **non-portable extension**. **-z**, **-\-leading-zeroes** : Makes bc(1) print all numbers greater than **-1** and less than **1**, and not equal to **0**, with a leading zero. This can be set for individual numbers with the **plz(x)**, plznl(x)**, **pnlz(x)**, and **pnlznl(x)** functions in the extended math library (see the **LIBRARY** section). This is a **non-portable extension**. **-e** *expr*, **-\-expression**=*expr* : Evaluates *expr*. If multiple expressions are given, they are evaluated in order. If files are given as well (see below), the expressions and files are evaluated in the order given. This means that if a file is given before an expression, the file is read in and evaluated first. If this option is given on the command-line (i.e., not in **DC_ENV_ARGS**, see the **ENVIRONMENT VARIABLES** section), then after processing all expressions and files, dc(1) will exit, unless **-** (**stdin**) was given as an argument at least once to **-f** or **-\-file**, whether on the command-line or in **DC_ENV_ARGS**. However, if any other **-e**, **-\-expression**, **-f**, or **-\-file** arguments are given after **-f-** or equivalent is given, dc(1) will give a fatal error and exit. This is a **non-portable extension**. **-f** *file*, **-\-file**=*file* : Reads in *file* and evaluates it, line by line, as though it were read through **stdin**. If expressions are also given (see above), the expressions are evaluated in the order given. If this option is given on the command-line (i.e., not in **DC_ENV_ARGS**, see the **ENVIRONMENT VARIABLES** section), then after processing all expressions and files, dc(1) will exit, unless **-** (**stdin**) was given as an argument at least once to **-f** or **-\-file**. However, if any other **-e**, **-\-expression**, **-f**, or **-\-file** arguments are given after **-f-** or equivalent is given, dc(1) will give a fatal error and exit. This is a **non-portable extension**. All long options are **non-portable extensions**. # STDIN If no files are given on the command-line and no files or expressions are given by the **-f**, **-\-file**, **-e**, or **-\-expression** options, then dc(1) read from **stdin**. However, there is a caveat to this. First, **stdin** is evaluated a line at a time. The only exception to this is if a string has been finished, but not ended. This means that, except for escaped brackets, all brackets must be balanced before dc(1) parses and executes. # STDOUT Any non-error output is written to **stdout**. In addition, if history (see the **HISTORY** section) and the prompt (see the **TTY MODE** section) are enabled, both are output to **stdout**. **Note**: Unlike other dc(1) implementations, this dc(1) will issue a fatal error (see the **EXIT STATUS** section) if it cannot write to **stdout**, so if **stdout** is closed, as in **dc >&-**, it will quit with an error. This is done so that dc(1) can report problems when **stdout** is redirected to a file. If there are scripts that depend on the behavior of other dc(1) implementations, it is recommended that those scripts be changed to redirect **stdout** to **/dev/null**. # STDERR Any error output is written to **stderr**. **Note**: Unlike other dc(1) implementations, this dc(1) will issue a fatal error (see the **EXIT STATUS** section) if it cannot write to **stderr**, so if **stderr** is closed, as in **dc 2>&-**, it will quit with an error. This is done so that dc(1) can exit with an error code when **stderr** is redirected to a file. If there are scripts that depend on the behavior of other dc(1) implementations, it is recommended that those scripts be changed to redirect **stderr** to **/dev/null**. # SYNTAX Each item in the input source code, either a number (see the **NUMBERS** section) or a command (see the **COMMANDS** section), is processed and executed, in order. Input is processed immediately when entered. **ibase** is a register (see the **REGISTERS** section) that determines how to interpret constant numbers. It is the "input" base, or the number base used for interpreting input numbers. **ibase** is initially **10**. The max allowable value for **ibase** is **16**. The min allowable value for **ibase** is **2**. The max allowable value for **ibase** can be queried in dc(1) programs with the **T** command. **obase** is a register (see the **REGISTERS** section) that determines how to output results. It is the "output" base, or the number base used for outputting numbers. **obase** is initially **10**. The max allowable value for **obase** is **DC_BASE_MAX** and can be queried with the **U** command. The min allowable value for **obase** is **2**. Values are output in the specified base. The *scale* of an expression is the number of digits in the result of the expression right of the decimal point, and **scale** is a register (see the **REGISTERS** section) that sets the precision of any operations (with exceptions). **scale** is initially **0**. **scale** cannot be negative. The max allowable value for **scale** can be queried in dc(1) programs with the **V** command. ## Comments Comments go from **#** until, and not including, the next newline. This is a **non-portable extension**. # NUMBERS Numbers are strings made up of digits, uppercase letters up to **F**, and at most **1** period for a radix. Numbers can have up to **DC_NUM_MAX** digits. Uppercase letters are equal to **9** + their position in the alphabet (i.e., **A** equals **10**, or **9+1**). If a digit or letter makes no sense with the current value of **ibase**, they are set to the value of the highest valid digit in **ibase**. Single-character numbers (i.e., **A** alone) take the value that they would have if they were valid digits, regardless of the value of **ibase**. This means that **A** alone always equals decimal **10** and **F** alone always equals decimal **15**. # COMMANDS The valid commands are listed below. ## Printing These commands are used for printing. **p** : Prints the value on top of the stack, whether number or string, and prints a newline after. This does not alter the stack. **n** : Prints the value on top of the stack, whether number or string, and pops it off of the stack. **P** : Pops a value off the stack. If the value is a number, it is truncated and the absolute value of the result is printed as though **obase** is **256** and each digit is interpreted as an 8-bit ASCII character, making it a byte stream. If the value is a string, it is printed without a trailing newline. This is a **non-portable extension**. **f** : Prints the entire contents of the stack, in order from newest to oldest, without altering anything. Users should use this command when they get lost. ## Arithmetic These are the commands used for arithmetic. **+** : The top two values are popped off the stack, added, and the result is pushed onto the stack. The *scale* of the result is equal to the max *scale* of both operands. **-** : The top two values are popped off the stack, subtracted, and the result is pushed onto the stack. The *scale* of the result is equal to the max *scale* of both operands. **\*** : The top two values are popped off the stack, multiplied, and the result is pushed onto the stack. If **a** is the *scale* of the first expression and **b** is the *scale* of the second expression, the *scale* of the result is equal to **min(a+b,max(scale,a,b))** where **min()** and **max()** return the obvious values. **/** : The top two values are popped off the stack, divided, and the result is pushed onto the stack. The *scale* of the result is equal to **scale**. The first value popped off of the stack must be non-zero. **%** : The top two values are popped off the stack, remaindered, and the result is pushed onto the stack. Remaindering is equivalent to 1) Computing **a/b** to current **scale**, and 2) Using the result of step 1 to calculate **a-(a/b)\*b** to *scale* **max(scale+scale(b),scale(a))**. The first value popped off of the stack must be non-zero. **~** : The top two values are popped off the stack, divided and remaindered, and the results (divided first, remainder second) are pushed onto the stack. This is equivalent to **x y / x y %** except that **x** and **y** are only evaluated once. The first value popped off of the stack must be non-zero. This is a **non-portable extension**. **\^** : The top two values are popped off the stack, the second is raised to the power of the first, and the result is pushed onto the stack. The *scale* of the result is equal to **scale**. The first value popped off of the stack must be an integer, and if that value is negative, the second value popped off of the stack must be non-zero. **v** : The top value is popped off the stack, its square root is computed, and the result is pushed onto the stack. The *scale* of the result is equal to **scale**. The value popped off of the stack must be non-negative. **\_** : If this command *immediately* precedes a number (i.e., no spaces or other commands), then that number is input as a negative number. Otherwise, the top value on the stack is popped and copied, and the copy is negated and pushed onto the stack. This behavior without a number is a **non-portable extension**. **b** : The top value is popped off the stack, and if it is zero, it is pushed back onto the stack. Otherwise, its absolute value is pushed onto the stack. This is a **non-portable extension**. **|** : The top three values are popped off the stack, a modular exponentiation is computed, and the result is pushed onto the stack. The first value popped is used as the reduction modulus and must be an integer and non-zero. The second value popped is used as the exponent and must be an integer and non-negative. The third value popped is the base and must be an integer. This is a **non-portable extension**. **G** : The top two values are popped off of the stack, they are compared, and a **1** is pushed if they are equal, or **0** otherwise. This is a **non-portable extension**. **N** : The top value is popped off of the stack, and if it a **0**, a **1** is pushed; otherwise, a **0** is pushed. This is a **non-portable extension**. **(** : The top two values are popped off of the stack, they are compared, and a **1** is pushed if the first is less than the second, or **0** otherwise. This is a **non-portable extension**. **{** : The top two values are popped off of the stack, they are compared, and a **1** is pushed if the first is less than or equal to the second, or **0** otherwise. This is a **non-portable extension**. **)** : The top two values are popped off of the stack, they are compared, and a **1** is pushed if the first is greater than the second, or **0** otherwise. This is a **non-portable extension**. **}** : The top two values are popped off of the stack, they are compared, and a **1** is pushed if the first is greater than or equal to the second, or **0** otherwise. This is a **non-portable extension**. **M** : The top two values are popped off of the stack. If they are both non-zero, a **1** is pushed onto the stack. If either of them is zero, or both of them are, then a **0** is pushed onto the stack. This is like the **&&** operator in bc(1), and it is *not* a short-circuit operator. This is a **non-portable extension**. **m** : The top two values are popped off of the stack. If at least one of them is non-zero, a **1** is pushed onto the stack. If both of them are zero, then a **0** is pushed onto the stack. This is like the **||** operator in bc(1), and it is *not* a short-circuit operator. This is a **non-portable extension**. ## Stack Control These commands control the stack. **c** : Removes all items from ("clears") the stack. **d** : Copies the item on top of the stack ("duplicates") and pushes the copy onto the stack. **r** : Swaps ("reverses") the two top items on the stack. **R** : Pops ("removes") the top value from the stack. ## Register Control These commands control registers (see the **REGISTERS** section). **s**_r_ : Pops the value off the top of the stack and stores it into register *r*. **l**_r_ : Copies the value in register *r* and pushes it onto the stack. This does not alter the contents of *r*. **S**_r_ : Pops the value off the top of the (main) stack and pushes it onto the stack of register *r*. The previous value of the register becomes inaccessible. **L**_r_ : Pops the value off the top of the stack for register *r* and push it onto the main stack. The previous value in the stack for register *r*, if any, is now accessible via the **l**_r_ command. ## Parameters These commands control the values of **ibase**, **obase**, and **scale**. Also see the **SYNTAX** section. **i** : Pops the value off of the top of the stack and uses it to set **ibase**, which must be between **2** and **16**, inclusive. If the value on top of the stack has any *scale*, the *scale* is ignored. **o** : Pops the value off of the top of the stack and uses it to set **obase**, which must be between **2** and **DC_BASE_MAX**, inclusive (see the **LIMITS** section). If the value on top of the stack has any *scale*, the *scale* is ignored. **k** : Pops the value off of the top of the stack and uses it to set **scale**, which must be non-negative. If the value on top of the stack has any *scale*, the *scale* is ignored. **I** : Pushes the current value of **ibase** onto the main stack. **O** : Pushes the current value of **obase** onto the main stack. **K** : Pushes the current value of **scale** onto the main stack. **T** : Pushes the maximum allowable value of **ibase** onto the main stack. This is a **non-portable extension**. **U** : Pushes the maximum allowable value of **obase** onto the main stack. This is a **non-portable extension**. **V** : Pushes the maximum allowable value of **scale** onto the main stack. This is a **non-portable extension**. ## Strings The following commands control strings. dc(1) can work with both numbers and strings, and registers (see the **REGISTERS** section) can hold both strings and numbers. dc(1) always knows whether the contents of a register are a string or a number. While arithmetic operations have to have numbers, and will print an error if given a string, other commands accept strings. Strings can also be executed as macros. For example, if the string **[1pR]** is executed as a macro, then the code **1pR** is executed, meaning that the **1** will be printed with a newline after and then popped from the stack. **\[**_characters_**\]** : Makes a string containing *characters* and pushes it onto the stack. If there are brackets (**\[** and **\]**) in the string, then they must be balanced. Unbalanced brackets can be escaped using a backslash (**\\**) character. If there is a backslash character in the string, the character after it (even another backslash) is put into the string verbatim, but the (first) backslash is not. **a** : The value on top of the stack is popped. If it is a number, it is truncated and its absolute value is taken. The result mod **256** is calculated. If that result is **0**, push an empty string; otherwise, push a one-character string where the character is the result of the mod interpreted as an ASCII character. If it is a string, then a new string is made. If the original string is empty, the new string is empty. If it is not, then the first character of the original string is used to create the new string as a one-character string. The new string is then pushed onto the stack. This is a **non-portable extension**. **x** : Pops a value off of the top of the stack. If it is a number, it is pushed back onto the stack. If it is a string, it is executed as a macro. This behavior is the norm whenever a macro is executed, whether by this command or by the conditional execution commands below. **\>**_r_ : Pops two values off of the stack that must be numbers and compares them. If the first value is greater than the second, then the contents of register *r* are executed. For example, **0 1>a** will execute the contents of register **a**, and **1 0>a** will not. If either or both of the values are not numbers, dc(1) will raise an error and reset (see the **RESET** section). **>**_r_**e**_s_ : Like the above, but will execute register *s* if the comparison fails. If either or both of the values are not numbers, dc(1) will raise an error and reset (see the **RESET** section). This is a **non-portable extension**. **!\>**_r_ : Pops two values off of the stack that must be numbers and compares them. If the first value is not greater than the second (less than or equal to), then the contents of register *r* are executed. If either or both of the values are not numbers, dc(1) will raise an error and reset (see the **RESET** section). **!\>**_r_**e**_s_ : Like the above, but will execute register *s* if the comparison fails. If either or both of the values are not numbers, dc(1) will raise an error and reset (see the **RESET** section). This is a **non-portable extension**. **\<**_r_ : Pops two values off of the stack that must be numbers and compares them. If the first value is less than the second, then the contents of register *r* are executed. If either or both of the values are not numbers, dc(1) will raise an error and reset (see the **RESET** section). **\<**_r_**e**_s_ : Like the above, but will execute register *s* if the comparison fails. If either or both of the values are not numbers, dc(1) will raise an error and reset (see the **RESET** section). This is a **non-portable extension**. **!\<**_r_ : Pops two values off of the stack that must be numbers and compares them. If the first value is not less than the second (greater than or equal to), then the contents of register *r* are executed. If either or both of the values are not numbers, dc(1) will raise an error and reset (see the **RESET** section). **!\<**_r_**e**_s_ : Like the above, but will execute register *s* if the comparison fails. If either or both of the values are not numbers, dc(1) will raise an error and reset (see the **RESET** section). This is a **non-portable extension**. **=**_r_ : Pops two values off of the stack that must be numbers and compares them. If the first value is equal to the second, then the contents of register *r* are executed. If either or both of the values are not numbers, dc(1) will raise an error and reset (see the **RESET** section). **=**_r_**e**_s_ : Like the above, but will execute register *s* if the comparison fails. If either or both of the values are not numbers, dc(1) will raise an error and reset (see the **RESET** section). This is a **non-portable extension**. **!=**_r_ : Pops two values off of the stack that must be numbers and compares them. If the first value is not equal to the second, then the contents of register *r* are executed. If either or both of the values are not numbers, dc(1) will raise an error and reset (see the **RESET** section). **!=**_r_**e**_s_ : Like the above, but will execute register *s* if the comparison fails. If either or both of the values are not numbers, dc(1) will raise an error and reset (see the **RESET** section). This is a **non-portable extension**. **?** : Reads a line from the **stdin** and executes it. This is to allow macros to request input from users. **q** : During execution of a macro, this exits the execution of that macro and the execution of the macro that executed it. If there are no macros, or only one macro executing, dc(1) exits. **Q** : Pops a value from the stack which must be non-negative and is used the number of macro executions to pop off of the execution stack. If the number of levels to pop is greater than the number of executing macros, dc(1) exits. **,** : Pushes the depth of the execution stack onto the stack. The execution stack is the stack of string executions. The number that is pushed onto the stack is exactly as many as is needed to make dc(1) exit with the **Q** command, so the sequence **,Q** will make dc(1) exit. ## Status These commands query status of the stack or its top value. **Z** : Pops a value off of the stack. If it is a number, calculates the number of significant decimal digits it has and pushes the result. It will push **1** if the argument is **0** with no decimal places. If it is a string, pushes the number of characters the string has. **X** : Pops a value off of the stack. If it is a number, pushes the *scale* of the value onto the stack. If it is a string, pushes **0**. **z** : Pushes the current depth of the stack (before execution of this command) onto the stack. **y**_r_ : Pushes the current stack depth of the register *r* onto the main stack. Because each register has a depth of **1** (with the value **0** in the top item) when dc(1) starts, dc(1) requires that each register's stack must always have at least one item; dc(1) will give an error and reset otherwise (see the **RESET** section). This means that this command will never push **0**. This is a **non-portable extension**. ## Arrays These commands manipulate arrays. **:**_r_ : Pops the top two values off of the stack. The second value will be stored in the array *r* (see the **REGISTERS** section), indexed by the first value. **;**_r_ : Pops the value on top of the stack and uses it as an index into the array *r*. The selected value is then pushed onto the stack. **Y**_r_ : Pushes the length of the array *r* onto the stack. This is a **non-portable extension**. ## Global Settings These commands retrieve global settings. These are the only commands that require multiple specific characters, and all of them begin with the letter **g**. Only the characters below are allowed after the character **g**; any other character produces a parse error (see the **ERRORS** section). **gl** : Pushes the line length set by **DC_LINE_LENGTH** (see the **ENVIRONMENT VARIABLES** section) onto the stack. **gz** : Pushes **0** onto the stack if the leading zero setting has not been enabled with the **-z** or **-\-leading-zeroes** options (see the **OPTIONS** section), non-zero otherwise. # REGISTERS Registers are names that can store strings, numbers, and arrays. (Number/string registers do not interfere with array registers.) Each register is also its own stack, so the current register value is the top of the stack for the register. All registers, when first referenced, have one value (**0**) in their stack, and it is a runtime error to attempt to pop that item off of the register stack. In non-extended register mode, a register name is just the single character that follows any command that needs a register name. The only exceptions are: a newline (**'\\n'**) and a left bracket (**'['**); it is a parse error for a newline or a left bracket to be used as a register name. ## Extended Register Mode Unlike most other dc(1) implentations, this dc(1) provides nearly unlimited amounts of registers, if extended register mode is enabled. If extended register mode is enabled (**-x** or **-\-extended-register** command-line arguments are given), then normal single character registers are used *unless* the character immediately following a command that needs a register name is a space (according to **isspace()**) and not a newline (**'\\n'**). In that case, the register name is found according to the regex **\[a-z\]\[a-z0-9\_\]\*** (like bc(1) identifiers), and it is a parse error if the next non-space characters do not match that regex. # RESET When dc(1) encounters an error or a signal that it has a non-default handler for, it resets. This means that several things happen. First, any macros that are executing are stopped and popped off the stack. The behavior is not unlike that of exceptions in programming languages. Then the execution point is set so that any code waiting to execute (after all macros returned) is skipped. Thus, when dc(1) resets, it skips any remaining code waiting to be executed. Then, if it is interactive mode, and the error was not a fatal error (see the **EXIT STATUS** section), it asks for more input; otherwise, it exits with the appropriate return code. # PERFORMANCE Most dc(1) implementations use **char** types to calculate the value of **1** decimal digit at a time, but that can be slow. This dc(1) does something different. It uses large integers to calculate more than **1** decimal digit at a time. If built in a environment where **DC_LONG_BIT** (see the **LIMITS** section) is **64**, then each integer has **9** decimal digits. If built in an environment where **DC_LONG_BIT** is **32** then each integer has **4** decimal digits. This value (the number of decimal digits per large integer) is called **DC_BASE_DIGS**. In addition, this dc(1) uses an even larger integer for overflow checking. This integer type depends on the value of **DC_LONG_BIT**, but is always at least twice as large as the integer type used to store digits. # LIMITS The following are the limits on dc(1): **DC_LONG_BIT** : The number of bits in the **long** type in the environment where dc(1) was built. This determines how many decimal digits can be stored in a single large integer (see the **PERFORMANCE** section). **DC_BASE_DIGS** : The number of decimal digits per large integer (see the **PERFORMANCE** section). Depends on **DC_LONG_BIT**. **DC_BASE_POW** : The max decimal number that each large integer can store (see **DC_BASE_DIGS**) plus **1**. Depends on **DC_BASE_DIGS**. **DC_OVERFLOW_MAX** : The max number that the overflow type (see the **PERFORMANCE** section) can hold. Depends on **DC_LONG_BIT**. **DC_BASE_MAX** : The maximum output base. Set at **DC_BASE_POW**. **DC_DIM_MAX** : The maximum size of arrays. Set at **SIZE_MAX-1**. **DC_SCALE_MAX** : The maximum **scale**. Set at **DC_OVERFLOW_MAX-1**. **DC_STRING_MAX** : The maximum length of strings. Set at **DC_OVERFLOW_MAX-1**. **DC_NAME_MAX** : The maximum length of identifiers. Set at **DC_OVERFLOW_MAX-1**. **DC_NUM_MAX** : The maximum length of a number (in decimal digits), which includes digits after the decimal point. Set at **DC_OVERFLOW_MAX-1**. Exponent : The maximum allowable exponent (positive or negative). Set at **DC_OVERFLOW_MAX**. Number of vars : The maximum number of vars/arrays. Set at **SIZE_MAX-1**. These limits are meant to be effectively non-existent; the limits are so large (at least on 64-bit machines) that there should not be any point at which they become a problem. In fact, memory should be exhausted before these limits should be hit. # ENVIRONMENT VARIABLES dc(1) recognizes the following environment variables: **DC_ENV_ARGS** : This is another way to give command-line arguments to dc(1). They should be in the same format as all other command-line arguments. These are always processed first, so any files given in **DC_ENV_ARGS** will be processed before arguments and files given on the command-line. This gives the user the ability to set up "standard" options and files to be used at every invocation. The most useful thing for such files to contain would be useful functions that the user might want every time dc(1) runs. Another use would be to use the **-e** option to set **scale** to a value other than **0**. The code that parses **DC_ENV_ARGS** will correctly handle quoted arguments, but it does not understand escape sequences. For example, the string **"/home/gavin/some dc file.dc"** will be correctly parsed, but the string **"/home/gavin/some \"dc\" file.dc"** will include the backslashes. The quote parsing will handle either kind of quotes, **'** or **"**. Thus, if you have a file with any number of single quotes in the name, you can use double quotes as the outside quotes, as in **"some 'dc' file.dc"**, and vice versa if you have a file with double quotes. However, handling a file with both kinds of quotes in **DC_ENV_ARGS** is not supported due to the complexity of the parsing, though such files are still supported on the command-line where the parsing is done by the shell. **DC_LINE_LENGTH** : If this environment variable exists and contains an integer that is greater than **1** and is less than **UINT16_MAX** (**2\^16-1**), dc(1) will output lines to that length, including the backslash newline combo. The default line length is **70**. The special value of **0** will disable line length checking and print numbers without regard to line length and without backslashes and newlines. **DC_SIGINT_RESET** : If dc(1) is not in interactive mode (see the **INTERACTIVE MODE** section), then this environment variable has no effect because dc(1) exits on **SIGINT** when not in interactive mode. However, when dc(1) is in interactive mode, then if this environment variable exists and contains an integer, a non-zero value makes dc(1) reset on **SIGINT**, rather than exit, and zero makes dc(1) exit. If this environment variable exists and is *not* an integer, then dc(1) will exit on **SIGINT**. This environment variable overrides the default, which can be queried with the **-h** or **-\-help** options. **DC_TTY_MODE** : If TTY mode is *not* available (see the **TTY MODE** section), then this environment variable has no effect. However, when TTY mode is available, then if this environment variable exists and contains an integer, then a non-zero value makes dc(1) use TTY mode, and zero makes dc(1) not use TTY mode. This environment variable overrides the default, which can be queried with the **-h** or **-\-help** options. **DC_PROMPT** : If TTY mode is *not* available (see the **TTY MODE** section), then this environment variable has no effect. However, when TTY mode is available, then if this environment variable exists and contains an integer, a non-zero value makes dc(1) use a prompt, and zero or a non-integer makes dc(1) not use a prompt. If this environment variable does not exist and **DC_TTY_MODE** does, then the value of the **DC_TTY_MODE** environment variable is used. This environment variable and the **DC_TTY_MODE** environment variable override the default, which can be queried with the **-h** or **-\-help** options. +**DC_EXPR_EXIT** + +: If any expressions or expression files are given on the command-line with + **-e**, **-\-expression**, **-f**, or **-\-file**, then if this environment + variable exists and contains an integer, a non-zero value makes dc(1) exit + after executing the expressions and expression files, and a non-zero value + makes dc(1) not exit. + + This environment variable overrides the default, which can be queried with + the **-h** or **-\-help** options. + # EXIT STATUS dc(1) returns the following exit statuses: **0** : No error. **1** : A math error occurred. This follows standard practice of using **1** for expected errors, since math errors will happen in the process of normal execution. Math errors include divide by **0**, taking the square root of a negative number, attempting to convert a negative number to a hardware integer, overflow when converting a number to a hardware integer, overflow when calculating the size of a number, and attempting to use a non-integer where an integer is required. Converting to a hardware integer happens for the second operand of the power (**\^**) operator. **2** : A parse error occurred. Parse errors include unexpected **EOF**, using an invalid character, failing to find the end of a string or comment, and using a token where it is invalid. **3** : A runtime error occurred. Runtime errors include assigning an invalid number to any global (**ibase**, **obase**, or **scale**), giving a bad expression to a **read()** call, calling **read()** inside of a **read()** call, type errors (including attempting to execute a number), and attempting an operation when the stack has too few elements. **4** : A fatal error occurred. Fatal errors include memory allocation errors, I/O errors, failing to open files, attempting to use files that do not have only ASCII characters (dc(1) only accepts ASCII characters), attempting to open a directory as a file, and giving invalid command-line options. The exit status **4** is special; when a fatal error occurs, dc(1) always exits and returns **4**, no matter what mode dc(1) is in. The other statuses will only be returned when dc(1) is not in interactive mode (see the **INTERACTIVE MODE** section), since dc(1) resets its state (see the **RESET** section) and accepts more input when one of those errors occurs in interactive mode. This is also the case when interactive mode is forced by the **-i** flag or **-\-interactive** option. These exit statuses allow dc(1) to be used in shell scripting with error checking, and its normal behavior can be forced by using the **-i** flag or **-\-interactive** option. # INTERACTIVE MODE Like bc(1), dc(1) has an interactive mode and a non-interactive mode. Interactive mode is turned on automatically when both **stdin** and **stdout** are hooked to a terminal, but the **-i** flag and **-\-interactive** option can turn it on in other situations. In interactive mode, dc(1) attempts to recover from errors (see the **RESET** section), and in normal execution, flushes **stdout** as soon as execution is done for the current input. dc(1) may also reset on **SIGINT** instead of exit, depending on the contents of, or default for, the **DC_SIGINT_RESET** environment variable (see the **ENVIRONMENT VARIABLES** section). # TTY MODE If **stdin**, **stdout**, and **stderr** are all connected to a TTY, then "TTY mode" is considered to be available, and thus, dc(1) can turn on TTY mode, subject to some settings. If there is the environment variable **DC_TTY_MODE** in the environment (see the **ENVIRONMENT VARIABLES** section), then if that environment variable contains a non-zero integer, dc(1) will turn on TTY mode when **stdin**, **stdout**, and **stderr** are all connected to a TTY. If the **DC_TTY_MODE** environment variable exists but is *not* a non-zero integer, then dc(1) will not turn TTY mode on. If the environment variable **DC_TTY_MODE** does *not* exist, the default setting is used. The default setting can be queried with the **-h** or **-\-help** options. TTY mode is different from interactive mode because interactive mode is required in the [bc(1) specification][1], and interactive mode requires only **stdin** and **stdout** to be connected to a terminal. ## Prompt If TTY mode is available, then a prompt can be enabled. Like TTY mode itself, it can be turned on or off with an environment variable: **DC_PROMPT** (see the **ENVIRONMENT VARIABLES** section). If the environment variable **DC_PROMPT** exists and is a non-zero integer, then the prompt is turned on when **stdin**, **stdout**, and **stderr** are connected to a TTY and the **-P** and **-\-no-prompt** options were not used. The read prompt will be turned on under the same conditions, except that the **-R** and **-\-no-read-prompt** options must also not be used. However, if **DC_PROMPT** does not exist, the prompt can be enabled or disabled with the **DC_TTY_MODE** environment variable, the **-P** and **-\-no-prompt** options, and the **-R** and **-\-no-read-prompt** options. See the **ENVIRONMENT VARIABLES** and **OPTIONS** sections for more details. # SIGNAL HANDLING Sending a **SIGINT** will cause dc(1) to do one of two things. If dc(1) is not in interactive mode (see the **INTERACTIVE MODE** section), or the **DC_SIGINT_RESET** environment variable (see the **ENVIRONMENT VARIABLES** section), or its default, is either not an integer or it is zero, dc(1) will exit. However, if dc(1) is in interactive mode, and the **DC_SIGINT_RESET** or its default is an integer and non-zero, then dc(1) will stop executing the current input and reset (see the **RESET** section) upon receiving a **SIGINT**. Note that "current input" can mean one of two things. If dc(1) is processing input from **stdin** in interactive mode, it will ask for more input. If dc(1) is processing input from a file in interactive mode, it will stop processing the file and start processing the next file, if one exists, or ask for input from **stdin** if no other file exists. This means that if a **SIGINT** is sent to dc(1) as it is executing a file, it can seem as though dc(1) did not respond to the signal since it will immediately start executing the next file. This is by design; most files that users execute when interacting with dc(1) have function definitions, which are quick to parse. If a file takes a long time to execute, there may be a bug in that file. The rest of the files could still be executed without problem, allowing the user to continue. **SIGTERM** and **SIGQUIT** cause dc(1) to clean up and exit, and it uses the default handler for all other signals. # SEE ALSO bc(1) # STANDARDS The dc(1) utility operators are compliant with the operators in the bc(1) [IEEE Std 1003.1-2017 (“POSIX.1-2017”)][1] specification. # BUGS None are known. Report bugs at https://git.yzena.com/gavin/bc. # AUTHOR Gavin D. Howard and contributors. [1]: https://pubs.opengroup.org/onlinepubs/9699919799/utilities/bc.html diff --git a/contrib/bc/manuals/dc/EN.1 b/contrib/bc/manuals/dc/EN.1 index beae0e46a9b6..8c2d14f57840 100644 --- a/contrib/bc/manuals/dc/EN.1 +++ b/contrib/bc/manuals/dc/EN.1 @@ -1,1338 +1,1351 @@ .\" .\" SPDX-License-Identifier: BSD-2-Clause .\" .\" Copyright (c) 2018-2021 Gavin D. Howard and contributors. .\" .\" Redistribution and use in source and binary forms, with or without .\" modification, are permitted provided that the following conditions are met: .\" .\" * Redistributions of source code must retain the above copyright notice, .\" this list of conditions and the following disclaimer. .\" .\" * Redistributions in binary form must reproduce the above copyright notice, .\" this list of conditions and the following disclaimer in the documentation .\" and/or other materials provided with the distribution. .\" .\" THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" .\" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE .\" IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE .\" ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE .\" LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR .\" CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF .\" SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS .\" INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN .\" CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) .\" ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE .\" POSSIBILITY OF SUCH DAMAGE. .\" .TH "DC" "1" "June 2021" "Gavin D. Howard" "General Commands Manual" .SH Name .PP dc - arbitrary-precision decimal reverse-Polish notation calculator .SH SYNOPSIS .PP \f[B]dc\f[R] [\f[B]-hiPRvVx\f[R]] [\f[B]--version\f[R]] [\f[B]--help\f[R]] [\f[B]--interactive\f[R]] [\f[B]--no-prompt\f[R]] [\f[B]--no-read-prompt\f[R]] [\f[B]--extended-register\f[R]] [\f[B]-e\f[R] \f[I]expr\f[R]] [\f[B]--expression\f[R]=\f[I]expr\f[R]\&...] [\f[B]-f\f[R] \f[I]file\f[R]\&...] [\f[B]--file\f[R]=\f[I]file\f[R]\&...] [\f[I]file\f[R]\&...] .SH DESCRIPTION .PP dc(1) is an arbitrary-precision calculator. It uses a stack (reverse Polish notation) to store numbers and results of computations. Arithmetic operations pop arguments off of the stack and push the results. .PP If no files are given on the command-line, then dc(1) reads from \f[B]stdin\f[R] (see the \f[B]STDIN\f[R] section). Otherwise, those files are processed, and dc(1) will then exit. .PP If a user wants to set up a standard environment, they can use \f[B]DC_ENV_ARGS\f[R] (see the \f[B]ENVIRONMENT VARIABLES\f[R] section). For example, if a user wants the \f[B]scale\f[R] always set to \f[B]10\f[R], they can set \f[B]DC_ENV_ARGS\f[R] to \f[B]-e 10k\f[R], and this dc(1) will always start with a \f[B]scale\f[R] of \f[B]10\f[R]. .SH OPTIONS .PP The following are the options that dc(1) accepts. .TP \f[B]-h\f[R], \f[B]--help\f[R] Prints a usage message and quits. .TP \f[B]-v\f[R], \f[B]-V\f[R], \f[B]--version\f[R] Print the version information (copyright header) and exit. .TP \f[B]-i\f[R], \f[B]--interactive\f[R] Forces interactive mode. (See the \f[B]INTERACTIVE MODE\f[R] section.) .RS .PP This is a \f[B]non-portable extension\f[R]. .RE .TP \f[B]-L\f[R], \f[B]--no-line-length\f[R] Disables line length checking and prints numbers without backslashes and newlines. In other words, this option sets \f[B]BC_LINE_LENGTH\f[R] to \f[B]0\f[R] (see the \f[B]ENVIRONMENT VARIABLES\f[R] section). .RS .PP This is a \f[B]non-portable extension\f[R]. .RE .TP \f[B]-P\f[R], \f[B]--no-prompt\f[R] Disables the prompt in TTY mode. (The prompt is only enabled in TTY mode. See the \f[B]TTY MODE\f[R] section.) This is mostly for those users that do not want a prompt or are not used to having them in dc(1). Most of those users would want to put this option in \f[B]DC_ENV_ARGS\f[R]. .RS .PP These options override the \f[B]DC_PROMPT\f[R] and \f[B]DC_TTY_MODE\f[R] environment variables (see the \f[B]ENVIRONMENT VARIABLES\f[R] section). .PP This is a \f[B]non-portable extension\f[R]. .RE .TP \f[B]-R\f[R], \f[B]--no-read-prompt\f[R] Disables the read prompt in TTY mode. (The read prompt is only enabled in TTY mode. See the \f[B]TTY MODE\f[R] section.) This is mostly for those users that do not want a read prompt or are not used to having them in dc(1). Most of those users would want to put this option in \f[B]BC_ENV_ARGS\f[R] (see the \f[B]ENVIRONMENT VARIABLES\f[R] section). This option is also useful in hash bang lines of dc(1) scripts that prompt for user input. .RS .PP This option does not disable the regular prompt because the read prompt is only used when the \f[B]?\f[R] command is used. .PP These options \f[I]do\f[R] override the \f[B]DC_PROMPT\f[R] and \f[B]DC_TTY_MODE\f[R] environment variables (see the \f[B]ENVIRONMENT VARIABLES\f[R] section), but only for the read prompt. .PP This is a \f[B]non-portable extension\f[R]. .RE .TP \f[B]-x\f[R] \f[B]--extended-register\f[R] Enables extended register mode. See the \f[I]Extended Register Mode\f[R] subsection of the \f[B]REGISTERS\f[R] section for more information. .RS .PP This is a \f[B]non-portable extension\f[R]. .RE .TP \f[B]-z\f[R], \f[B]--leading-zeroes\f[R] Makes bc(1) print all numbers greater than \f[B]-1\f[R] and less than \f[B]1\f[R], and not equal to \f[B]0\f[R], with a leading zero. .RS .PP This can be set for individual numbers with the \f[B]plz(x)\f[R], plznl(x)**, \f[B]pnlz(x)\f[R], and \f[B]pnlznl(x)\f[R] functions in the extended math library (see the \f[B]LIBRARY\f[R] section). .PP This is a \f[B]non-portable extension\f[R]. .RE .TP \f[B]-e\f[R] \f[I]expr\f[R], \f[B]--expression\f[R]=\f[I]expr\f[R] Evaluates \f[I]expr\f[R]. If multiple expressions are given, they are evaluated in order. If files are given as well (see below), the expressions and files are evaluated in the order given. This means that if a file is given before an expression, the file is read in and evaluated first. .RS .PP If this option is given on the command-line (i.e., not in \f[B]DC_ENV_ARGS\f[R], see the \f[B]ENVIRONMENT VARIABLES\f[R] section), then after processing all expressions and files, dc(1) will exit, unless \f[B]-\f[R] (\f[B]stdin\f[R]) was given as an argument at least once to \f[B]-f\f[R] or \f[B]--file\f[R], whether on the command-line or in \f[B]DC_ENV_ARGS\f[R]. However, if any other \f[B]-e\f[R], \f[B]--expression\f[R], \f[B]-f\f[R], or \f[B]--file\f[R] arguments are given after \f[B]-f-\f[R] or equivalent is given, dc(1) will give a fatal error and exit. .PP This is a \f[B]non-portable extension\f[R]. .RE .TP \f[B]-f\f[R] \f[I]file\f[R], \f[B]--file\f[R]=\f[I]file\f[R] Reads in \f[I]file\f[R] and evaluates it, line by line, as though it were read through \f[B]stdin\f[R]. If expressions are also given (see above), the expressions are evaluated in the order given. .RS .PP If this option is given on the command-line (i.e., not in \f[B]DC_ENV_ARGS\f[R], see the \f[B]ENVIRONMENT VARIABLES\f[R] section), then after processing all expressions and files, dc(1) will exit, unless \f[B]-\f[R] (\f[B]stdin\f[R]) was given as an argument at least once to \f[B]-f\f[R] or \f[B]--file\f[R]. However, if any other \f[B]-e\f[R], \f[B]--expression\f[R], \f[B]-f\f[R], or \f[B]--file\f[R] arguments are given after \f[B]-f-\f[R] or equivalent is given, dc(1) will give a fatal error and exit. .PP This is a \f[B]non-portable extension\f[R]. .RE .PP All long options are \f[B]non-portable extensions\f[R]. .SH STDIN .PP If no files are given on the command-line and no files or expressions are given by the \f[B]-f\f[R], \f[B]--file\f[R], \f[B]-e\f[R], or \f[B]--expression\f[R] options, then dc(1) read from \f[B]stdin\f[R]. .PP However, there is a caveat to this. .PP First, \f[B]stdin\f[R] is evaluated a line at a time. The only exception to this is if a string has been finished, but not ended. This means that, except for escaped brackets, all brackets must be balanced before dc(1) parses and executes. .SH STDOUT .PP Any non-error output is written to \f[B]stdout\f[R]. In addition, if history (see the \f[B]HISTORY\f[R] section) and the prompt (see the \f[B]TTY MODE\f[R] section) are enabled, both are output to \f[B]stdout\f[R]. .PP \f[B]Note\f[R]: Unlike other dc(1) implementations, this dc(1) will issue a fatal error (see the \f[B]EXIT STATUS\f[R] section) if it cannot write to \f[B]stdout\f[R], so if \f[B]stdout\f[R] is closed, as in \f[B]dc >&-\f[R], it will quit with an error. This is done so that dc(1) can report problems when \f[B]stdout\f[R] is redirected to a file. .PP If there are scripts that depend on the behavior of other dc(1) implementations, it is recommended that those scripts be changed to redirect \f[B]stdout\f[R] to \f[B]/dev/null\f[R]. .SH STDERR .PP Any error output is written to \f[B]stderr\f[R]. .PP \f[B]Note\f[R]: Unlike other dc(1) implementations, this dc(1) will issue a fatal error (see the \f[B]EXIT STATUS\f[R] section) if it cannot write to \f[B]stderr\f[R], so if \f[B]stderr\f[R] is closed, as in \f[B]dc 2>&-\f[R], it will quit with an error. This is done so that dc(1) can exit with an error code when \f[B]stderr\f[R] is redirected to a file. .PP If there are scripts that depend on the behavior of other dc(1) implementations, it is recommended that those scripts be changed to redirect \f[B]stderr\f[R] to \f[B]/dev/null\f[R]. .SH SYNTAX .PP Each item in the input source code, either a number (see the \f[B]NUMBERS\f[R] section) or a command (see the \f[B]COMMANDS\f[R] section), is processed and executed, in order. Input is processed immediately when entered. .PP \f[B]ibase\f[R] is a register (see the \f[B]REGISTERS\f[R] section) that determines how to interpret constant numbers. It is the \[lq]input\[rq] base, or the number base used for interpreting input numbers. \f[B]ibase\f[R] is initially \f[B]10\f[R]. The max allowable value for \f[B]ibase\f[R] is \f[B]16\f[R]. The min allowable value for \f[B]ibase\f[R] is \f[B]2\f[R]. The max allowable value for \f[B]ibase\f[R] can be queried in dc(1) programs with the \f[B]T\f[R] command. .PP \f[B]obase\f[R] is a register (see the \f[B]REGISTERS\f[R] section) that determines how to output results. It is the \[lq]output\[rq] base, or the number base used for outputting numbers. \f[B]obase\f[R] is initially \f[B]10\f[R]. The max allowable value for \f[B]obase\f[R] is \f[B]DC_BASE_MAX\f[R] and can be queried with the \f[B]U\f[R] command. The min allowable value for \f[B]obase\f[R] is \f[B]2\f[R]. Values are output in the specified base. .PP The \f[I]scale\f[R] of an expression is the number of digits in the result of the expression right of the decimal point, and \f[B]scale\f[R] is a register (see the \f[B]REGISTERS\f[R] section) that sets the precision of any operations (with exceptions). \f[B]scale\f[R] is initially \f[B]0\f[R]. \f[B]scale\f[R] cannot be negative. The max allowable value for \f[B]scale\f[R] can be queried in dc(1) programs with the \f[B]V\f[R] command. .SS Comments .PP Comments go from \f[B]#\f[R] until, and not including, the next newline. This is a \f[B]non-portable extension\f[R]. .SH NUMBERS .PP Numbers are strings made up of digits, uppercase letters up to \f[B]F\f[R], and at most \f[B]1\f[R] period for a radix. Numbers can have up to \f[B]DC_NUM_MAX\f[R] digits. Uppercase letters are equal to \f[B]9\f[R] + their position in the alphabet (i.e., \f[B]A\f[R] equals \f[B]10\f[R], or \f[B]9+1\f[R]). If a digit or letter makes no sense with the current value of \f[B]ibase\f[R], they are set to the value of the highest valid digit in \f[B]ibase\f[R]. .PP Single-character numbers (i.e., \f[B]A\f[R] alone) take the value that they would have if they were valid digits, regardless of the value of \f[B]ibase\f[R]. This means that \f[B]A\f[R] alone always equals decimal \f[B]10\f[R] and \f[B]F\f[R] alone always equals decimal \f[B]15\f[R]. .SH COMMANDS .PP The valid commands are listed below. .SS Printing .PP These commands are used for printing. .TP \f[B]p\f[R] Prints the value on top of the stack, whether number or string, and prints a newline after. .RS .PP This does not alter the stack. .RE .TP \f[B]n\f[R] Prints the value on top of the stack, whether number or string, and pops it off of the stack. .TP \f[B]P\f[R] Pops a value off the stack. .RS .PP If the value is a number, it is truncated and the absolute value of the result is printed as though \f[B]obase\f[R] is \f[B]256\f[R] and each digit is interpreted as an 8-bit ASCII character, making it a byte stream. .PP If the value is a string, it is printed without a trailing newline. .PP This is a \f[B]non-portable extension\f[R]. .RE .TP \f[B]f\f[R] Prints the entire contents of the stack, in order from newest to oldest, without altering anything. .RS .PP Users should use this command when they get lost. .RE .SS Arithmetic .PP These are the commands used for arithmetic. .TP \f[B]+\f[R] The top two values are popped off the stack, added, and the result is pushed onto the stack. The \f[I]scale\f[R] of the result is equal to the max \f[I]scale\f[R] of both operands. .TP \f[B]-\f[R] The top two values are popped off the stack, subtracted, and the result is pushed onto the stack. The \f[I]scale\f[R] of the result is equal to the max \f[I]scale\f[R] of both operands. .TP \f[B]*\f[R] The top two values are popped off the stack, multiplied, and the result is pushed onto the stack. If \f[B]a\f[R] is the \f[I]scale\f[R] of the first expression and \f[B]b\f[R] is the \f[I]scale\f[R] of the second expression, the \f[I]scale\f[R] of the result is equal to \f[B]min(a+b,max(scale,a,b))\f[R] where \f[B]min()\f[R] and \f[B]max()\f[R] return the obvious values. .TP \f[B]/\f[R] The top two values are popped off the stack, divided, and the result is pushed onto the stack. The \f[I]scale\f[R] of the result is equal to \f[B]scale\f[R]. .RS .PP The first value popped off of the stack must be non-zero. .RE .TP \f[B]%\f[R] The top two values are popped off the stack, remaindered, and the result is pushed onto the stack. .RS .PP Remaindering is equivalent to 1) Computing \f[B]a/b\f[R] to current \f[B]scale\f[R], and 2) Using the result of step 1 to calculate \f[B]a-(a/b)*b\f[R] to \f[I]scale\f[R] \f[B]max(scale+scale(b),scale(a))\f[R]. .PP The first value popped off of the stack must be non-zero. .RE .TP \f[B]\[ti]\f[R] The top two values are popped off the stack, divided and remaindered, and the results (divided first, remainder second) are pushed onto the stack. This is equivalent to \f[B]x y / x y %\f[R] except that \f[B]x\f[R] and \f[B]y\f[R] are only evaluated once. .RS .PP The first value popped off of the stack must be non-zero. .PP This is a \f[B]non-portable extension\f[R]. .RE .TP \f[B]\[ha]\f[R] The top two values are popped off the stack, the second is raised to the power of the first, and the result is pushed onto the stack. The \f[I]scale\f[R] of the result is equal to \f[B]scale\f[R]. .RS .PP The first value popped off of the stack must be an integer, and if that value is negative, the second value popped off of the stack must be non-zero. .RE .TP \f[B]v\f[R] The top value is popped off the stack, its square root is computed, and the result is pushed onto the stack. The \f[I]scale\f[R] of the result is equal to \f[B]scale\f[R]. .RS .PP The value popped off of the stack must be non-negative. .RE .TP \f[B]_\f[R] If this command \f[I]immediately\f[R] precedes a number (i.e., no spaces or other commands), then that number is input as a negative number. .RS .PP Otherwise, the top value on the stack is popped and copied, and the copy is negated and pushed onto the stack. This behavior without a number is a \f[B]non-portable extension\f[R]. .RE .TP \f[B]b\f[R] The top value is popped off the stack, and if it is zero, it is pushed back onto the stack. Otherwise, its absolute value is pushed onto the stack. .RS .PP This is a \f[B]non-portable extension\f[R]. .RE .TP \f[B]|\f[R] The top three values are popped off the stack, a modular exponentiation is computed, and the result is pushed onto the stack. .RS .PP The first value popped is used as the reduction modulus and must be an integer and non-zero. The second value popped is used as the exponent and must be an integer and non-negative. The third value popped is the base and must be an integer. .PP This is a \f[B]non-portable extension\f[R]. .RE .TP \f[B]G\f[R] The top two values are popped off of the stack, they are compared, and a \f[B]1\f[R] is pushed if they are equal, or \f[B]0\f[R] otherwise. .RS .PP This is a \f[B]non-portable extension\f[R]. .RE .TP \f[B]N\f[R] The top value is popped off of the stack, and if it a \f[B]0\f[R], a \f[B]1\f[R] is pushed; otherwise, a \f[B]0\f[R] is pushed. .RS .PP This is a \f[B]non-portable extension\f[R]. .RE .TP \f[B](\f[R] The top two values are popped off of the stack, they are compared, and a \f[B]1\f[R] is pushed if the first is less than the second, or \f[B]0\f[R] otherwise. .RS .PP This is a \f[B]non-portable extension\f[R]. .RE .TP \f[B]{\f[R] The top two values are popped off of the stack, they are compared, and a \f[B]1\f[R] is pushed if the first is less than or equal to the second, or \f[B]0\f[R] otherwise. .RS .PP This is a \f[B]non-portable extension\f[R]. .RE .TP \f[B])\f[R] The top two values are popped off of the stack, they are compared, and a \f[B]1\f[R] is pushed if the first is greater than the second, or \f[B]0\f[R] otherwise. .RS .PP This is a \f[B]non-portable extension\f[R]. .RE .TP \f[B]}\f[R] The top two values are popped off of the stack, they are compared, and a \f[B]1\f[R] is pushed if the first is greater than or equal to the second, or \f[B]0\f[R] otherwise. .RS .PP This is a \f[B]non-portable extension\f[R]. .RE .TP \f[B]M\f[R] The top two values are popped off of the stack. If they are both non-zero, a \f[B]1\f[R] is pushed onto the stack. If either of them is zero, or both of them are, then a \f[B]0\f[R] is pushed onto the stack. .RS .PP This is like the \f[B]&&\f[R] operator in bc(1), and it is \f[I]not\f[R] a short-circuit operator. .PP This is a \f[B]non-portable extension\f[R]. .RE .TP \f[B]m\f[R] The top two values are popped off of the stack. If at least one of them is non-zero, a \f[B]1\f[R] is pushed onto the stack. If both of them are zero, then a \f[B]0\f[R] is pushed onto the stack. .RS .PP This is like the \f[B]||\f[R] operator in bc(1), and it is \f[I]not\f[R] a short-circuit operator. .PP This is a \f[B]non-portable extension\f[R]. .RE .SS Stack Control .PP These commands control the stack. .TP \f[B]c\f[R] Removes all items from (\[lq]clears\[rq]) the stack. .TP \f[B]d\f[R] Copies the item on top of the stack (\[lq]duplicates\[rq]) and pushes the copy onto the stack. .TP \f[B]r\f[R] Swaps (\[lq]reverses\[rq]) the two top items on the stack. .TP \f[B]R\f[R] Pops (\[lq]removes\[rq]) the top value from the stack. .SS Register Control .PP These commands control registers (see the \f[B]REGISTERS\f[R] section). .TP \f[B]s\f[R]\f[I]r\f[R] Pops the value off the top of the stack and stores it into register \f[I]r\f[R]. .TP \f[B]l\f[R]\f[I]r\f[R] Copies the value in register \f[I]r\f[R] and pushes it onto the stack. This does not alter the contents of \f[I]r\f[R]. .TP \f[B]S\f[R]\f[I]r\f[R] Pops the value off the top of the (main) stack and pushes it onto the stack of register \f[I]r\f[R]. The previous value of the register becomes inaccessible. .TP \f[B]L\f[R]\f[I]r\f[R] Pops the value off the top of the stack for register \f[I]r\f[R] and push it onto the main stack. The previous value in the stack for register \f[I]r\f[R], if any, is now accessible via the \f[B]l\f[R]\f[I]r\f[R] command. .SS Parameters .PP These commands control the values of \f[B]ibase\f[R], \f[B]obase\f[R], and \f[B]scale\f[R]. Also see the \f[B]SYNTAX\f[R] section. .TP \f[B]i\f[R] Pops the value off of the top of the stack and uses it to set \f[B]ibase\f[R], which must be between \f[B]2\f[R] and \f[B]16\f[R], inclusive. .RS .PP If the value on top of the stack has any \f[I]scale\f[R], the \f[I]scale\f[R] is ignored. .RE .TP \f[B]o\f[R] Pops the value off of the top of the stack and uses it to set \f[B]obase\f[R], which must be between \f[B]2\f[R] and \f[B]DC_BASE_MAX\f[R], inclusive (see the \f[B]LIMITS\f[R] section). .RS .PP If the value on top of the stack has any \f[I]scale\f[R], the \f[I]scale\f[R] is ignored. .RE .TP \f[B]k\f[R] Pops the value off of the top of the stack and uses it to set \f[B]scale\f[R], which must be non-negative. .RS .PP If the value on top of the stack has any \f[I]scale\f[R], the \f[I]scale\f[R] is ignored. .RE .TP \f[B]I\f[R] Pushes the current value of \f[B]ibase\f[R] onto the main stack. .TP \f[B]O\f[R] Pushes the current value of \f[B]obase\f[R] onto the main stack. .TP \f[B]K\f[R] Pushes the current value of \f[B]scale\f[R] onto the main stack. .TP \f[B]T\f[R] Pushes the maximum allowable value of \f[B]ibase\f[R] onto the main stack. .RS .PP This is a \f[B]non-portable extension\f[R]. .RE .TP \f[B]U\f[R] Pushes the maximum allowable value of \f[B]obase\f[R] onto the main stack. .RS .PP This is a \f[B]non-portable extension\f[R]. .RE .TP \f[B]V\f[R] Pushes the maximum allowable value of \f[B]scale\f[R] onto the main stack. .RS .PP This is a \f[B]non-portable extension\f[R]. .RE .SS Strings .PP The following commands control strings. .PP dc(1) can work with both numbers and strings, and registers (see the \f[B]REGISTERS\f[R] section) can hold both strings and numbers. dc(1) always knows whether the contents of a register are a string or a number. .PP While arithmetic operations have to have numbers, and will print an error if given a string, other commands accept strings. .PP Strings can also be executed as macros. For example, if the string \f[B][1pR]\f[R] is executed as a macro, then the code \f[B]1pR\f[R] is executed, meaning that the \f[B]1\f[R] will be printed with a newline after and then popped from the stack. .TP \f[B][\f[R]\f[I]characters\f[R]\f[B]]\f[R] Makes a string containing \f[I]characters\f[R] and pushes it onto the stack. .RS .PP If there are brackets (\f[B][\f[R] and \f[B]]\f[R]) in the string, then they must be balanced. Unbalanced brackets can be escaped using a backslash (\f[B]\[rs]\f[R]) character. .PP If there is a backslash character in the string, the character after it (even another backslash) is put into the string verbatim, but the (first) backslash is not. .RE .TP \f[B]a\f[R] The value on top of the stack is popped. .RS .PP If it is a number, it is truncated and its absolute value is taken. The result mod \f[B]256\f[R] is calculated. If that result is \f[B]0\f[R], push an empty string; otherwise, push a one-character string where the character is the result of the mod interpreted as an ASCII character. .PP If it is a string, then a new string is made. If the original string is empty, the new string is empty. If it is not, then the first character of the original string is used to create the new string as a one-character string. The new string is then pushed onto the stack. .PP This is a \f[B]non-portable extension\f[R]. .RE .TP \f[B]x\f[R] Pops a value off of the top of the stack. .RS .PP If it is a number, it is pushed back onto the stack. .PP If it is a string, it is executed as a macro. .PP This behavior is the norm whenever a macro is executed, whether by this command or by the conditional execution commands below. .RE .TP \f[B]>\f[R]\f[I]r\f[R] Pops two values off of the stack that must be numbers and compares them. If the first value is greater than the second, then the contents of register \f[I]r\f[R] are executed. .RS .PP For example, \f[B]0 1>a\f[R] will execute the contents of register \f[B]a\f[R], and \f[B]1 0>a\f[R] will not. .PP If either or both of the values are not numbers, dc(1) will raise an error and reset (see the \f[B]RESET\f[R] section). .RE .TP \f[B]>\f[R]\f[I]r\f[R]\f[B]e\f[R]\f[I]s\f[R] Like the above, but will execute register \f[I]s\f[R] if the comparison fails. .RS .PP If either or both of the values are not numbers, dc(1) will raise an error and reset (see the \f[B]RESET\f[R] section). .PP This is a \f[B]non-portable extension\f[R]. .RE .TP \f[B]!>\f[R]\f[I]r\f[R] Pops two values off of the stack that must be numbers and compares them. If the first value is not greater than the second (less than or equal to), then the contents of register \f[I]r\f[R] are executed. .RS .PP If either or both of the values are not numbers, dc(1) will raise an error and reset (see the \f[B]RESET\f[R] section). .RE .TP \f[B]!>\f[R]\f[I]r\f[R]\f[B]e\f[R]\f[I]s\f[R] Like the above, but will execute register \f[I]s\f[R] if the comparison fails. .RS .PP If either or both of the values are not numbers, dc(1) will raise an error and reset (see the \f[B]RESET\f[R] section). .PP This is a \f[B]non-portable extension\f[R]. .RE .TP \f[B]<\f[R]\f[I]r\f[R] Pops two values off of the stack that must be numbers and compares them. If the first value is less than the second, then the contents of register \f[I]r\f[R] are executed. .RS .PP If either or both of the values are not numbers, dc(1) will raise an error and reset (see the \f[B]RESET\f[R] section). .RE .TP \f[B]<\f[R]\f[I]r\f[R]\f[B]e\f[R]\f[I]s\f[R] Like the above, but will execute register \f[I]s\f[R] if the comparison fails. .RS .PP If either or both of the values are not numbers, dc(1) will raise an error and reset (see the \f[B]RESET\f[R] section). .PP This is a \f[B]non-portable extension\f[R]. .RE .TP \f[B]!<\f[R]\f[I]r\f[R] Pops two values off of the stack that must be numbers and compares them. If the first value is not less than the second (greater than or equal to), then the contents of register \f[I]r\f[R] are executed. .RS .PP If either or both of the values are not numbers, dc(1) will raise an error and reset (see the \f[B]RESET\f[R] section). .RE .TP \f[B]!<\f[R]\f[I]r\f[R]\f[B]e\f[R]\f[I]s\f[R] Like the above, but will execute register \f[I]s\f[R] if the comparison fails. .RS .PP If either or both of the values are not numbers, dc(1) will raise an error and reset (see the \f[B]RESET\f[R] section). .PP This is a \f[B]non-portable extension\f[R]. .RE .TP \f[B]=\f[R]\f[I]r\f[R] Pops two values off of the stack that must be numbers and compares them. If the first value is equal to the second, then the contents of register \f[I]r\f[R] are executed. .RS .PP If either or both of the values are not numbers, dc(1) will raise an error and reset (see the \f[B]RESET\f[R] section). .RE .TP \f[B]=\f[R]\f[I]r\f[R]\f[B]e\f[R]\f[I]s\f[R] Like the above, but will execute register \f[I]s\f[R] if the comparison fails. .RS .PP If either or both of the values are not numbers, dc(1) will raise an error and reset (see the \f[B]RESET\f[R] section). .PP This is a \f[B]non-portable extension\f[R]. .RE .TP \f[B]!=\f[R]\f[I]r\f[R] Pops two values off of the stack that must be numbers and compares them. If the first value is not equal to the second, then the contents of register \f[I]r\f[R] are executed. .RS .PP If either or both of the values are not numbers, dc(1) will raise an error and reset (see the \f[B]RESET\f[R] section). .RE .TP \f[B]!=\f[R]\f[I]r\f[R]\f[B]e\f[R]\f[I]s\f[R] Like the above, but will execute register \f[I]s\f[R] if the comparison fails. .RS .PP If either or both of the values are not numbers, dc(1) will raise an error and reset (see the \f[B]RESET\f[R] section). .PP This is a \f[B]non-portable extension\f[R]. .RE .TP \f[B]?\f[R] Reads a line from the \f[B]stdin\f[R] and executes it. This is to allow macros to request input from users. .TP \f[B]q\f[R] During execution of a macro, this exits the execution of that macro and the execution of the macro that executed it. If there are no macros, or only one macro executing, dc(1) exits. .TP \f[B]Q\f[R] Pops a value from the stack which must be non-negative and is used the number of macro executions to pop off of the execution stack. If the number of levels to pop is greater than the number of executing macros, dc(1) exits. .TP \f[B],\f[R] Pushes the depth of the execution stack onto the stack. The execution stack is the stack of string executions. The number that is pushed onto the stack is exactly as many as is needed to make dc(1) exit with the \f[B]Q\f[R] command, so the sequence \f[B],Q\f[R] will make dc(1) exit. .SS Status .PP These commands query status of the stack or its top value. .TP \f[B]Z\f[R] Pops a value off of the stack. .RS .PP If it is a number, calculates the number of significant decimal digits it has and pushes the result. It will push \f[B]1\f[R] if the argument is \f[B]0\f[R] with no decimal places. .PP If it is a string, pushes the number of characters the string has. .RE .TP \f[B]X\f[R] Pops a value off of the stack. .RS .PP If it is a number, pushes the \f[I]scale\f[R] of the value onto the stack. .PP If it is a string, pushes \f[B]0\f[R]. .RE .TP \f[B]z\f[R] Pushes the current depth of the stack (before execution of this command) onto the stack. .TP \f[B]y\f[R]\f[I]r\f[R] Pushes the current stack depth of the register \f[I]r\f[R] onto the main stack. .RS .PP Because each register has a depth of \f[B]1\f[R] (with the value \f[B]0\f[R] in the top item) when dc(1) starts, dc(1) requires that each register\[cq]s stack must always have at least one item; dc(1) will give an error and reset otherwise (see the \f[B]RESET\f[R] section). This means that this command will never push \f[B]0\f[R]. .PP This is a \f[B]non-portable extension\f[R]. .RE .SS Arrays .PP These commands manipulate arrays. .TP \f[B]:\f[R]\f[I]r\f[R] Pops the top two values off of the stack. The second value will be stored in the array \f[I]r\f[R] (see the \f[B]REGISTERS\f[R] section), indexed by the first value. .TP \f[B];\f[R]\f[I]r\f[R] Pops the value on top of the stack and uses it as an index into the array \f[I]r\f[R]. The selected value is then pushed onto the stack. .TP \f[B]Y\f[R]\f[I]r\f[R] Pushes the length of the array \f[I]r\f[R] onto the stack. .RS .PP This is a \f[B]non-portable extension\f[R]. .RE .SS Global Settings .PP These commands retrieve global settings. These are the only commands that require multiple specific characters, and all of them begin with the letter \f[B]g\f[R]. Only the characters below are allowed after the character \f[B]g\f[R]; any other character produces a parse error (see the \f[B]ERRORS\f[R] section). .TP \f[B]gl\f[R] Pushes the line length set by \f[B]DC_LINE_LENGTH\f[R] (see the \f[B]ENVIRONMENT VARIABLES\f[R] section) onto the stack. .TP \f[B]gz\f[R] Pushes \f[B]0\f[R] onto the stack if the leading zero setting has not been enabled with the \f[B]-z\f[R] or \f[B]--leading-zeroes\f[R] options (see the \f[B]OPTIONS\f[R] section), non-zero otherwise. .SH REGISTERS .PP Registers are names that can store strings, numbers, and arrays. (Number/string registers do not interfere with array registers.) .PP Each register is also its own stack, so the current register value is the top of the stack for the register. All registers, when first referenced, have one value (\f[B]0\f[R]) in their stack, and it is a runtime error to attempt to pop that item off of the register stack. .PP In non-extended register mode, a register name is just the single character that follows any command that needs a register name. The only exceptions are: a newline (\f[B]`\[rs]n'\f[R]) and a left bracket (\f[B]`['\f[R]); it is a parse error for a newline or a left bracket to be used as a register name. .SS Extended Register Mode .PP Unlike most other dc(1) implentations, this dc(1) provides nearly unlimited amounts of registers, if extended register mode is enabled. .PP If extended register mode is enabled (\f[B]-x\f[R] or \f[B]--extended-register\f[R] command-line arguments are given), then normal single character registers are used \f[I]unless\f[R] the character immediately following a command that needs a register name is a space (according to \f[B]isspace()\f[R]) and not a newline (\f[B]`\[rs]n'\f[R]). .PP In that case, the register name is found according to the regex \f[B][a-z][a-z0-9_]*\f[R] (like bc(1) identifiers), and it is a parse error if the next non-space characters do not match that regex. .SH RESET .PP When dc(1) encounters an error or a signal that it has a non-default handler for, it resets. This means that several things happen. .PP First, any macros that are executing are stopped and popped off the stack. The behavior is not unlike that of exceptions in programming languages. Then the execution point is set so that any code waiting to execute (after all macros returned) is skipped. .PP Thus, when dc(1) resets, it skips any remaining code waiting to be executed. Then, if it is interactive mode, and the error was not a fatal error (see the \f[B]EXIT STATUS\f[R] section), it asks for more input; otherwise, it exits with the appropriate return code. .SH PERFORMANCE .PP Most dc(1) implementations use \f[B]char\f[R] types to calculate the value of \f[B]1\f[R] decimal digit at a time, but that can be slow. This dc(1) does something different. .PP It uses large integers to calculate more than \f[B]1\f[R] decimal digit at a time. If built in a environment where \f[B]DC_LONG_BIT\f[R] (see the \f[B]LIMITS\f[R] section) is \f[B]64\f[R], then each integer has \f[B]9\f[R] decimal digits. If built in an environment where \f[B]DC_LONG_BIT\f[R] is \f[B]32\f[R] then each integer has \f[B]4\f[R] decimal digits. This value (the number of decimal digits per large integer) is called \f[B]DC_BASE_DIGS\f[R]. .PP In addition, this dc(1) uses an even larger integer for overflow checking. This integer type depends on the value of \f[B]DC_LONG_BIT\f[R], but is always at least twice as large as the integer type used to store digits. .SH LIMITS .PP The following are the limits on dc(1): .TP \f[B]DC_LONG_BIT\f[R] The number of bits in the \f[B]long\f[R] type in the environment where dc(1) was built. This determines how many decimal digits can be stored in a single large integer (see the \f[B]PERFORMANCE\f[R] section). .TP \f[B]DC_BASE_DIGS\f[R] The number of decimal digits per large integer (see the \f[B]PERFORMANCE\f[R] section). Depends on \f[B]DC_LONG_BIT\f[R]. .TP \f[B]DC_BASE_POW\f[R] The max decimal number that each large integer can store (see \f[B]DC_BASE_DIGS\f[R]) plus \f[B]1\f[R]. Depends on \f[B]DC_BASE_DIGS\f[R]. .TP \f[B]DC_OVERFLOW_MAX\f[R] The max number that the overflow type (see the \f[B]PERFORMANCE\f[R] section) can hold. Depends on \f[B]DC_LONG_BIT\f[R]. .TP \f[B]DC_BASE_MAX\f[R] The maximum output base. Set at \f[B]DC_BASE_POW\f[R]. .TP \f[B]DC_DIM_MAX\f[R] The maximum size of arrays. Set at \f[B]SIZE_MAX-1\f[R]. .TP \f[B]DC_SCALE_MAX\f[R] The maximum \f[B]scale\f[R]. Set at \f[B]DC_OVERFLOW_MAX-1\f[R]. .TP \f[B]DC_STRING_MAX\f[R] The maximum length of strings. Set at \f[B]DC_OVERFLOW_MAX-1\f[R]. .TP \f[B]DC_NAME_MAX\f[R] The maximum length of identifiers. Set at \f[B]DC_OVERFLOW_MAX-1\f[R]. .TP \f[B]DC_NUM_MAX\f[R] The maximum length of a number (in decimal digits), which includes digits after the decimal point. Set at \f[B]DC_OVERFLOW_MAX-1\f[R]. .TP Exponent The maximum allowable exponent (positive or negative). Set at \f[B]DC_OVERFLOW_MAX\f[R]. .TP Number of vars The maximum number of vars/arrays. Set at \f[B]SIZE_MAX-1\f[R]. .PP These limits are meant to be effectively non-existent; the limits are so large (at least on 64-bit machines) that there should not be any point at which they become a problem. In fact, memory should be exhausted before these limits should be hit. .SH ENVIRONMENT VARIABLES .PP dc(1) recognizes the following environment variables: .TP \f[B]DC_ENV_ARGS\f[R] This is another way to give command-line arguments to dc(1). They should be in the same format as all other command-line arguments. These are always processed first, so any files given in \f[B]DC_ENV_ARGS\f[R] will be processed before arguments and files given on the command-line. This gives the user the ability to set up \[lq]standard\[rq] options and files to be used at every invocation. The most useful thing for such files to contain would be useful functions that the user might want every time dc(1) runs. Another use would be to use the \f[B]-e\f[R] option to set \f[B]scale\f[R] to a value other than \f[B]0\f[R]. .RS .PP The code that parses \f[B]DC_ENV_ARGS\f[R] will correctly handle quoted arguments, but it does not understand escape sequences. For example, the string \f[B]\[lq]/home/gavin/some dc file.dc\[rq]\f[R] will be correctly parsed, but the string \f[B]\[lq]/home/gavin/some \[dq]dc\[dq] file.dc\[rq]\f[R] will include the backslashes. .PP The quote parsing will handle either kind of quotes, \f[B]\[cq]\f[R] or \f[B]\[lq]\f[R]. Thus, if you have a file with any number of single quotes in the name, you can use double quotes as the outside quotes, as in \f[B]\[lq]some `dc' file.dc\[rq]\f[R], and vice versa if you have a file with double quotes. However, handling a file with both kinds of quotes in \f[B]DC_ENV_ARGS\f[R] is not supported due to the complexity of the parsing, though such files are still supported on the command-line where the parsing is done by the shell. .RE .TP \f[B]DC_LINE_LENGTH\f[R] If this environment variable exists and contains an integer that is greater than \f[B]1\f[R] and is less than \f[B]UINT16_MAX\f[R] (\f[B]2\[ha]16-1\f[R]), dc(1) will output lines to that length, including the backslash newline combo. The default line length is \f[B]70\f[R]. .RS .PP The special value of \f[B]0\f[R] will disable line length checking and print numbers without regard to line length and without backslashes and newlines. .RE .TP \f[B]DC_SIGINT_RESET\f[R] If dc(1) is not in interactive mode (see the \f[B]INTERACTIVE MODE\f[R] section), then this environment variable has no effect because dc(1) exits on \f[B]SIGINT\f[R] when not in interactive mode. .RS .PP However, when dc(1) is in interactive mode, then if this environment variable exists and contains an integer, a non-zero value makes dc(1) reset on \f[B]SIGINT\f[R], rather than exit, and zero makes dc(1) exit. If this environment variable exists and is \f[I]not\f[R] an integer, then dc(1) will exit on \f[B]SIGINT\f[R]. .PP This environment variable overrides the default, which can be queried with the \f[B]-h\f[R] or \f[B]--help\f[R] options. .RE .TP \f[B]DC_TTY_MODE\f[R] If TTY mode is \f[I]not\f[R] available (see the \f[B]TTY MODE\f[R] section), then this environment variable has no effect. .RS .PP However, when TTY mode is available, then if this environment variable exists and contains an integer, then a non-zero value makes dc(1) use TTY mode, and zero makes dc(1) not use TTY mode. .PP This environment variable overrides the default, which can be queried with the \f[B]-h\f[R] or \f[B]--help\f[R] options. .RE .TP \f[B]DC_PROMPT\f[R] If TTY mode is \f[I]not\f[R] available (see the \f[B]TTY MODE\f[R] section), then this environment variable has no effect. .RS .PP However, when TTY mode is available, then if this environment variable exists and contains an integer, a non-zero value makes dc(1) use a prompt, and zero or a non-integer makes dc(1) not use a prompt. If this environment variable does not exist and \f[B]DC_TTY_MODE\f[R] does, then the value of the \f[B]DC_TTY_MODE\f[R] environment variable is used. .PP This environment variable and the \f[B]DC_TTY_MODE\f[R] environment variable override the default, which can be queried with the \f[B]-h\f[R] or \f[B]--help\f[R] options. .RE +.TP +\f[B]DC_EXPR_EXIT\f[R] +If any expressions or expression files are given on the command-line +with \f[B]-e\f[R], \f[B]--expression\f[R], \f[B]-f\f[R], or +\f[B]--file\f[R], then if this environment variable exists and contains +an integer, a non-zero value makes dc(1) exit after executing the +expressions and expression files, and a non-zero value makes dc(1) not +exit. +.RS +.PP +This environment variable overrides the default, which can be queried +with the \f[B]-h\f[R] or \f[B]--help\f[R] options. +.RE .SH EXIT STATUS .PP dc(1) returns the following exit statuses: .TP \f[B]0\f[R] No error. .TP \f[B]1\f[R] A math error occurred. This follows standard practice of using \f[B]1\f[R] for expected errors, since math errors will happen in the process of normal execution. .RS .PP Math errors include divide by \f[B]0\f[R], taking the square root of a negative number, attempting to convert a negative number to a hardware integer, overflow when converting a number to a hardware integer, overflow when calculating the size of a number, and attempting to use a non-integer where an integer is required. .PP Converting to a hardware integer happens for the second operand of the power (\f[B]\[ha]\f[R]) operator. .RE .TP \f[B]2\f[R] A parse error occurred. .RS .PP Parse errors include unexpected \f[B]EOF\f[R], using an invalid character, failing to find the end of a string or comment, and using a token where it is invalid. .RE .TP \f[B]3\f[R] A runtime error occurred. .RS .PP Runtime errors include assigning an invalid number to any global (\f[B]ibase\f[R], \f[B]obase\f[R], or \f[B]scale\f[R]), giving a bad expression to a \f[B]read()\f[R] call, calling \f[B]read()\f[R] inside of a \f[B]read()\f[R] call, type errors (including attempting to execute a number), and attempting an operation when the stack has too few elements. .RE .TP \f[B]4\f[R] A fatal error occurred. .RS .PP Fatal errors include memory allocation errors, I/O errors, failing to open files, attempting to use files that do not have only ASCII characters (dc(1) only accepts ASCII characters), attempting to open a directory as a file, and giving invalid command-line options. .RE .PP The exit status \f[B]4\f[R] is special; when a fatal error occurs, dc(1) always exits and returns \f[B]4\f[R], no matter what mode dc(1) is in. .PP The other statuses will only be returned when dc(1) is not in interactive mode (see the \f[B]INTERACTIVE MODE\f[R] section), since dc(1) resets its state (see the \f[B]RESET\f[R] section) and accepts more input when one of those errors occurs in interactive mode. This is also the case when interactive mode is forced by the \f[B]-i\f[R] flag or \f[B]--interactive\f[R] option. .PP These exit statuses allow dc(1) to be used in shell scripting with error checking, and its normal behavior can be forced by using the \f[B]-i\f[R] flag or \f[B]--interactive\f[R] option. .SH INTERACTIVE MODE .PP Like bc(1), dc(1) has an interactive mode and a non-interactive mode. Interactive mode is turned on automatically when both \f[B]stdin\f[R] and \f[B]stdout\f[R] are hooked to a terminal, but the \f[B]-i\f[R] flag and \f[B]--interactive\f[R] option can turn it on in other situations. .PP In interactive mode, dc(1) attempts to recover from errors (see the \f[B]RESET\f[R] section), and in normal execution, flushes \f[B]stdout\f[R] as soon as execution is done for the current input. dc(1) may also reset on \f[B]SIGINT\f[R] instead of exit, depending on the contents of, or default for, the \f[B]DC_SIGINT_RESET\f[R] environment variable (see the \f[B]ENVIRONMENT VARIABLES\f[R] section). .SH TTY MODE .PP If \f[B]stdin\f[R], \f[B]stdout\f[R], and \f[B]stderr\f[R] are all connected to a TTY, then \[lq]TTY mode\[rq] is considered to be available, and thus, dc(1) can turn on TTY mode, subject to some settings. .PP If there is the environment variable \f[B]DC_TTY_MODE\f[R] in the environment (see the \f[B]ENVIRONMENT VARIABLES\f[R] section), then if that environment variable contains a non-zero integer, dc(1) will turn on TTY mode when \f[B]stdin\f[R], \f[B]stdout\f[R], and \f[B]stderr\f[R] are all connected to a TTY. If the \f[B]DC_TTY_MODE\f[R] environment variable exists but is \f[I]not\f[R] a non-zero integer, then dc(1) will not turn TTY mode on. .PP If the environment variable \f[B]DC_TTY_MODE\f[R] does \f[I]not\f[R] exist, the default setting is used. The default setting can be queried with the \f[B]-h\f[R] or \f[B]--help\f[R] options. .PP TTY mode is different from interactive mode because interactive mode is required in the bc(1) specification (https://pubs.opengroup.org/onlinepubs/9699919799/utilities/bc.html), and interactive mode requires only \f[B]stdin\f[R] and \f[B]stdout\f[R] to be connected to a terminal. .SS Command-Line History .PP Command-line history is only enabled if TTY mode is, i.e., that \f[B]stdin\f[R], \f[B]stdout\f[R], and \f[B]stderr\f[R] are connected to a TTY and the \f[B]DC_TTY_MODE\f[R] environment variable (see the \f[B]ENVIRONMENT VARIABLES\f[R] section) and its default do not disable TTY mode. See the \f[B]COMMAND LINE HISTORY\f[R] section for more information. .SS Prompt .PP If TTY mode is available, then a prompt can be enabled. Like TTY mode itself, it can be turned on or off with an environment variable: \f[B]DC_PROMPT\f[R] (see the \f[B]ENVIRONMENT VARIABLES\f[R] section). .PP If the environment variable \f[B]DC_PROMPT\f[R] exists and is a non-zero integer, then the prompt is turned on when \f[B]stdin\f[R], \f[B]stdout\f[R], and \f[B]stderr\f[R] are connected to a TTY and the \f[B]-P\f[R] and \f[B]--no-prompt\f[R] options were not used. The read prompt will be turned on under the same conditions, except that the \f[B]-R\f[R] and \f[B]--no-read-prompt\f[R] options must also not be used. .PP However, if \f[B]DC_PROMPT\f[R] does not exist, the prompt can be enabled or disabled with the \f[B]DC_TTY_MODE\f[R] environment variable, the \f[B]-P\f[R] and \f[B]--no-prompt\f[R] options, and the \f[B]-R\f[R] and \f[B]--no-read-prompt\f[R] options. See the \f[B]ENVIRONMENT VARIABLES\f[R] and \f[B]OPTIONS\f[R] sections for more details. .SH SIGNAL HANDLING .PP Sending a \f[B]SIGINT\f[R] will cause dc(1) to do one of two things. .PP If dc(1) is not in interactive mode (see the \f[B]INTERACTIVE MODE\f[R] section), or the \f[B]DC_SIGINT_RESET\f[R] environment variable (see the \f[B]ENVIRONMENT VARIABLES\f[R] section), or its default, is either not an integer or it is zero, dc(1) will exit. .PP However, if dc(1) is in interactive mode, and the \f[B]DC_SIGINT_RESET\f[R] or its default is an integer and non-zero, then dc(1) will stop executing the current input and reset (see the \f[B]RESET\f[R] section) upon receiving a \f[B]SIGINT\f[R]. .PP Note that \[lq]current input\[rq] can mean one of two things. If dc(1) is processing input from \f[B]stdin\f[R] in interactive mode, it will ask for more input. If dc(1) is processing input from a file in interactive mode, it will stop processing the file and start processing the next file, if one exists, or ask for input from \f[B]stdin\f[R] if no other file exists. .PP This means that if a \f[B]SIGINT\f[R] is sent to dc(1) as it is executing a file, it can seem as though dc(1) did not respond to the signal since it will immediately start executing the next file. This is by design; most files that users execute when interacting with dc(1) have function definitions, which are quick to parse. If a file takes a long time to execute, there may be a bug in that file. The rest of the files could still be executed without problem, allowing the user to continue. .PP \f[B]SIGTERM\f[R] and \f[B]SIGQUIT\f[R] cause dc(1) to clean up and exit, and it uses the default handler for all other signals. The one exception is \f[B]SIGHUP\f[R]; in that case, and only when dc(1) is in TTY mode (see the \f[B]TTY MODE\f[R] section), a \f[B]SIGHUP\f[R] will cause dc(1) to clean up and exit. .SH COMMAND LINE HISTORY .PP dc(1) supports interactive command-line editing. .PP If dc(1) can be in TTY mode (see the \f[B]TTY MODE\f[R] section), history can be enabled. This means that command-line history can only be enabled when \f[B]stdin\f[R], \f[B]stdout\f[R], and \f[B]stderr\f[R] are all connected to a TTY. .PP Like TTY mode itself, it can be turned on or off with the environment variable \f[B]DC_TTY_MODE\f[R] (see the \f[B]ENVIRONMENT VARIABLES\f[R] section). .PP \f[B]Note\f[R]: tabs are converted to 8 spaces. .SH SEE ALSO .PP bc(1) .SH STANDARDS .PP The dc(1) utility operators are compliant with the operators in the bc(1) IEEE Std 1003.1-2017 (\[lq]POSIX.1-2017\[rq]) (https://pubs.opengroup.org/onlinepubs/9699919799/utilities/bc.html) specification. .SH BUGS .PP None are known. Report bugs at https://git.yzena.com/gavin/bc. .SH AUTHOR .PP Gavin D. Howard and contributors. diff --git a/contrib/bc/manuals/dc/EN.1.md b/contrib/bc/manuals/dc/EN.1.md index db6f27f34576..03836923c00e 100644 --- a/contrib/bc/manuals/dc/EN.1.md +++ b/contrib/bc/manuals/dc/EN.1.md @@ -1,1212 +1,1223 @@ # Name dc - arbitrary-precision decimal reverse-Polish notation calculator # SYNOPSIS **dc** [**-hiPRvVx**] [**-\-version**] [**-\-help**] [**-\-interactive**] [**-\-no-prompt**] [**-\-no-read-prompt**] [**-\-extended-register**] [**-e** *expr*] [**-\-expression**=*expr*...] [**-f** *file*...] [**-\-file**=*file*...] [*file*...] # DESCRIPTION dc(1) is an arbitrary-precision calculator. It uses a stack (reverse Polish notation) to store numbers and results of computations. Arithmetic operations pop arguments off of the stack and push the results. If no files are given on the command-line, then dc(1) reads from **stdin** (see the **STDIN** section). Otherwise, those files are processed, and dc(1) will then exit. If a user wants to set up a standard environment, they can use **DC_ENV_ARGS** (see the **ENVIRONMENT VARIABLES** section). For example, if a user wants the **scale** always set to **10**, they can set **DC_ENV_ARGS** to **-e 10k**, and this dc(1) will always start with a **scale** of **10**. # OPTIONS The following are the options that dc(1) accepts. **-h**, **-\-help** : Prints a usage message and quits. **-v**, **-V**, **-\-version** : Print the version information (copyright header) and exit. **-i**, **-\-interactive** : Forces interactive mode. (See the **INTERACTIVE MODE** section.) This is a **non-portable extension**. **-L**, **-\-no-line-length** : Disables line length checking and prints numbers without backslashes and newlines. In other words, this option sets **BC_LINE_LENGTH** to **0** (see the **ENVIRONMENT VARIABLES** section). This is a **non-portable extension**. **-P**, **-\-no-prompt** : Disables the prompt in TTY mode. (The prompt is only enabled in TTY mode. See the **TTY MODE** section.) This is mostly for those users that do not want a prompt or are not used to having them in dc(1). Most of those users would want to put this option in **DC_ENV_ARGS**. These options override the **DC_PROMPT** and **DC_TTY_MODE** environment variables (see the **ENVIRONMENT VARIABLES** section). This is a **non-portable extension**. **-R**, **-\-no-read-prompt** : Disables the read prompt in TTY mode. (The read prompt is only enabled in TTY mode. See the **TTY MODE** section.) This is mostly for those users that do not want a read prompt or are not used to having them in dc(1). Most of those users would want to put this option in **BC_ENV_ARGS** (see the **ENVIRONMENT VARIABLES** section). This option is also useful in hash bang lines of dc(1) scripts that prompt for user input. This option does not disable the regular prompt because the read prompt is only used when the **?** command is used. These options *do* override the **DC_PROMPT** and **DC_TTY_MODE** environment variables (see the **ENVIRONMENT VARIABLES** section), but only for the read prompt. This is a **non-portable extension**. **-x** **-\-extended-register** : Enables extended register mode. See the *Extended Register Mode* subsection of the **REGISTERS** section for more information. This is a **non-portable extension**. **-z**, **-\-leading-zeroes** : Makes bc(1) print all numbers greater than **-1** and less than **1**, and not equal to **0**, with a leading zero. This can be set for individual numbers with the **plz(x)**, plznl(x)**, **pnlz(x)**, and **pnlznl(x)** functions in the extended math library (see the **LIBRARY** section). This is a **non-portable extension**. **-e** *expr*, **-\-expression**=*expr* : Evaluates *expr*. If multiple expressions are given, they are evaluated in order. If files are given as well (see below), the expressions and files are evaluated in the order given. This means that if a file is given before an expression, the file is read in and evaluated first. If this option is given on the command-line (i.e., not in **DC_ENV_ARGS**, see the **ENVIRONMENT VARIABLES** section), then after processing all expressions and files, dc(1) will exit, unless **-** (**stdin**) was given as an argument at least once to **-f** or **-\-file**, whether on the command-line or in **DC_ENV_ARGS**. However, if any other **-e**, **-\-expression**, **-f**, or **-\-file** arguments are given after **-f-** or equivalent is given, dc(1) will give a fatal error and exit. This is a **non-portable extension**. **-f** *file*, **-\-file**=*file* : Reads in *file* and evaluates it, line by line, as though it were read through **stdin**. If expressions are also given (see above), the expressions are evaluated in the order given. If this option is given on the command-line (i.e., not in **DC_ENV_ARGS**, see the **ENVIRONMENT VARIABLES** section), then after processing all expressions and files, dc(1) will exit, unless **-** (**stdin**) was given as an argument at least once to **-f** or **-\-file**. However, if any other **-e**, **-\-expression**, **-f**, or **-\-file** arguments are given after **-f-** or equivalent is given, dc(1) will give a fatal error and exit. This is a **non-portable extension**. All long options are **non-portable extensions**. # STDIN If no files are given on the command-line and no files or expressions are given by the **-f**, **-\-file**, **-e**, or **-\-expression** options, then dc(1) read from **stdin**. However, there is a caveat to this. First, **stdin** is evaluated a line at a time. The only exception to this is if a string has been finished, but not ended. This means that, except for escaped brackets, all brackets must be balanced before dc(1) parses and executes. # STDOUT Any non-error output is written to **stdout**. In addition, if history (see the **HISTORY** section) and the prompt (see the **TTY MODE** section) are enabled, both are output to **stdout**. **Note**: Unlike other dc(1) implementations, this dc(1) will issue a fatal error (see the **EXIT STATUS** section) if it cannot write to **stdout**, so if **stdout** is closed, as in **dc >&-**, it will quit with an error. This is done so that dc(1) can report problems when **stdout** is redirected to a file. If there are scripts that depend on the behavior of other dc(1) implementations, it is recommended that those scripts be changed to redirect **stdout** to **/dev/null**. # STDERR Any error output is written to **stderr**. **Note**: Unlike other dc(1) implementations, this dc(1) will issue a fatal error (see the **EXIT STATUS** section) if it cannot write to **stderr**, so if **stderr** is closed, as in **dc 2>&-**, it will quit with an error. This is done so that dc(1) can exit with an error code when **stderr** is redirected to a file. If there are scripts that depend on the behavior of other dc(1) implementations, it is recommended that those scripts be changed to redirect **stderr** to **/dev/null**. # SYNTAX Each item in the input source code, either a number (see the **NUMBERS** section) or a command (see the **COMMANDS** section), is processed and executed, in order. Input is processed immediately when entered. **ibase** is a register (see the **REGISTERS** section) that determines how to interpret constant numbers. It is the "input" base, or the number base used for interpreting input numbers. **ibase** is initially **10**. The max allowable value for **ibase** is **16**. The min allowable value for **ibase** is **2**. The max allowable value for **ibase** can be queried in dc(1) programs with the **T** command. **obase** is a register (see the **REGISTERS** section) that determines how to output results. It is the "output" base, or the number base used for outputting numbers. **obase** is initially **10**. The max allowable value for **obase** is **DC_BASE_MAX** and can be queried with the **U** command. The min allowable value for **obase** is **2**. Values are output in the specified base. The *scale* of an expression is the number of digits in the result of the expression right of the decimal point, and **scale** is a register (see the **REGISTERS** section) that sets the precision of any operations (with exceptions). **scale** is initially **0**. **scale** cannot be negative. The max allowable value for **scale** can be queried in dc(1) programs with the **V** command. ## Comments Comments go from **#** until, and not including, the next newline. This is a **non-portable extension**. # NUMBERS Numbers are strings made up of digits, uppercase letters up to **F**, and at most **1** period for a radix. Numbers can have up to **DC_NUM_MAX** digits. Uppercase letters are equal to **9** + their position in the alphabet (i.e., **A** equals **10**, or **9+1**). If a digit or letter makes no sense with the current value of **ibase**, they are set to the value of the highest valid digit in **ibase**. Single-character numbers (i.e., **A** alone) take the value that they would have if they were valid digits, regardless of the value of **ibase**. This means that **A** alone always equals decimal **10** and **F** alone always equals decimal **15**. # COMMANDS The valid commands are listed below. ## Printing These commands are used for printing. **p** : Prints the value on top of the stack, whether number or string, and prints a newline after. This does not alter the stack. **n** : Prints the value on top of the stack, whether number or string, and pops it off of the stack. **P** : Pops a value off the stack. If the value is a number, it is truncated and the absolute value of the result is printed as though **obase** is **256** and each digit is interpreted as an 8-bit ASCII character, making it a byte stream. If the value is a string, it is printed without a trailing newline. This is a **non-portable extension**. **f** : Prints the entire contents of the stack, in order from newest to oldest, without altering anything. Users should use this command when they get lost. ## Arithmetic These are the commands used for arithmetic. **+** : The top two values are popped off the stack, added, and the result is pushed onto the stack. The *scale* of the result is equal to the max *scale* of both operands. **-** : The top two values are popped off the stack, subtracted, and the result is pushed onto the stack. The *scale* of the result is equal to the max *scale* of both operands. **\*** : The top two values are popped off the stack, multiplied, and the result is pushed onto the stack. If **a** is the *scale* of the first expression and **b** is the *scale* of the second expression, the *scale* of the result is equal to **min(a+b,max(scale,a,b))** where **min()** and **max()** return the obvious values. **/** : The top two values are popped off the stack, divided, and the result is pushed onto the stack. The *scale* of the result is equal to **scale**. The first value popped off of the stack must be non-zero. **%** : The top two values are popped off the stack, remaindered, and the result is pushed onto the stack. Remaindering is equivalent to 1) Computing **a/b** to current **scale**, and 2) Using the result of step 1 to calculate **a-(a/b)\*b** to *scale* **max(scale+scale(b),scale(a))**. The first value popped off of the stack must be non-zero. **~** : The top two values are popped off the stack, divided and remaindered, and the results (divided first, remainder second) are pushed onto the stack. This is equivalent to **x y / x y %** except that **x** and **y** are only evaluated once. The first value popped off of the stack must be non-zero. This is a **non-portable extension**. **\^** : The top two values are popped off the stack, the second is raised to the power of the first, and the result is pushed onto the stack. The *scale* of the result is equal to **scale**. The first value popped off of the stack must be an integer, and if that value is negative, the second value popped off of the stack must be non-zero. **v** : The top value is popped off the stack, its square root is computed, and the result is pushed onto the stack. The *scale* of the result is equal to **scale**. The value popped off of the stack must be non-negative. **\_** : If this command *immediately* precedes a number (i.e., no spaces or other commands), then that number is input as a negative number. Otherwise, the top value on the stack is popped and copied, and the copy is negated and pushed onto the stack. This behavior without a number is a **non-portable extension**. **b** : The top value is popped off the stack, and if it is zero, it is pushed back onto the stack. Otherwise, its absolute value is pushed onto the stack. This is a **non-portable extension**. **|** : The top three values are popped off the stack, a modular exponentiation is computed, and the result is pushed onto the stack. The first value popped is used as the reduction modulus and must be an integer and non-zero. The second value popped is used as the exponent and must be an integer and non-negative. The third value popped is the base and must be an integer. This is a **non-portable extension**. **G** : The top two values are popped off of the stack, they are compared, and a **1** is pushed if they are equal, or **0** otherwise. This is a **non-portable extension**. **N** : The top value is popped off of the stack, and if it a **0**, a **1** is pushed; otherwise, a **0** is pushed. This is a **non-portable extension**. **(** : The top two values are popped off of the stack, they are compared, and a **1** is pushed if the first is less than the second, or **0** otherwise. This is a **non-portable extension**. **{** : The top two values are popped off of the stack, they are compared, and a **1** is pushed if the first is less than or equal to the second, or **0** otherwise. This is a **non-portable extension**. **)** : The top two values are popped off of the stack, they are compared, and a **1** is pushed if the first is greater than the second, or **0** otherwise. This is a **non-portable extension**. **}** : The top two values are popped off of the stack, they are compared, and a **1** is pushed if the first is greater than or equal to the second, or **0** otherwise. This is a **non-portable extension**. **M** : The top two values are popped off of the stack. If they are both non-zero, a **1** is pushed onto the stack. If either of them is zero, or both of them are, then a **0** is pushed onto the stack. This is like the **&&** operator in bc(1), and it is *not* a short-circuit operator. This is a **non-portable extension**. **m** : The top two values are popped off of the stack. If at least one of them is non-zero, a **1** is pushed onto the stack. If both of them are zero, then a **0** is pushed onto the stack. This is like the **||** operator in bc(1), and it is *not* a short-circuit operator. This is a **non-portable extension**. ## Stack Control These commands control the stack. **c** : Removes all items from ("clears") the stack. **d** : Copies the item on top of the stack ("duplicates") and pushes the copy onto the stack. **r** : Swaps ("reverses") the two top items on the stack. **R** : Pops ("removes") the top value from the stack. ## Register Control These commands control registers (see the **REGISTERS** section). **s**_r_ : Pops the value off the top of the stack and stores it into register *r*. **l**_r_ : Copies the value in register *r* and pushes it onto the stack. This does not alter the contents of *r*. **S**_r_ : Pops the value off the top of the (main) stack and pushes it onto the stack of register *r*. The previous value of the register becomes inaccessible. **L**_r_ : Pops the value off the top of the stack for register *r* and push it onto the main stack. The previous value in the stack for register *r*, if any, is now accessible via the **l**_r_ command. ## Parameters These commands control the values of **ibase**, **obase**, and **scale**. Also see the **SYNTAX** section. **i** : Pops the value off of the top of the stack and uses it to set **ibase**, which must be between **2** and **16**, inclusive. If the value on top of the stack has any *scale*, the *scale* is ignored. **o** : Pops the value off of the top of the stack and uses it to set **obase**, which must be between **2** and **DC_BASE_MAX**, inclusive (see the **LIMITS** section). If the value on top of the stack has any *scale*, the *scale* is ignored. **k** : Pops the value off of the top of the stack and uses it to set **scale**, which must be non-negative. If the value on top of the stack has any *scale*, the *scale* is ignored. **I** : Pushes the current value of **ibase** onto the main stack. **O** : Pushes the current value of **obase** onto the main stack. **K** : Pushes the current value of **scale** onto the main stack. **T** : Pushes the maximum allowable value of **ibase** onto the main stack. This is a **non-portable extension**. **U** : Pushes the maximum allowable value of **obase** onto the main stack. This is a **non-portable extension**. **V** : Pushes the maximum allowable value of **scale** onto the main stack. This is a **non-portable extension**. ## Strings The following commands control strings. dc(1) can work with both numbers and strings, and registers (see the **REGISTERS** section) can hold both strings and numbers. dc(1) always knows whether the contents of a register are a string or a number. While arithmetic operations have to have numbers, and will print an error if given a string, other commands accept strings. Strings can also be executed as macros. For example, if the string **[1pR]** is executed as a macro, then the code **1pR** is executed, meaning that the **1** will be printed with a newline after and then popped from the stack. **\[**_characters_**\]** : Makes a string containing *characters* and pushes it onto the stack. If there are brackets (**\[** and **\]**) in the string, then they must be balanced. Unbalanced brackets can be escaped using a backslash (**\\**) character. If there is a backslash character in the string, the character after it (even another backslash) is put into the string verbatim, but the (first) backslash is not. **a** : The value on top of the stack is popped. If it is a number, it is truncated and its absolute value is taken. The result mod **256** is calculated. If that result is **0**, push an empty string; otherwise, push a one-character string where the character is the result of the mod interpreted as an ASCII character. If it is a string, then a new string is made. If the original string is empty, the new string is empty. If it is not, then the first character of the original string is used to create the new string as a one-character string. The new string is then pushed onto the stack. This is a **non-portable extension**. **x** : Pops a value off of the top of the stack. If it is a number, it is pushed back onto the stack. If it is a string, it is executed as a macro. This behavior is the norm whenever a macro is executed, whether by this command or by the conditional execution commands below. **\>**_r_ : Pops two values off of the stack that must be numbers and compares them. If the first value is greater than the second, then the contents of register *r* are executed. For example, **0 1>a** will execute the contents of register **a**, and **1 0>a** will not. If either or both of the values are not numbers, dc(1) will raise an error and reset (see the **RESET** section). **>**_r_**e**_s_ : Like the above, but will execute register *s* if the comparison fails. If either or both of the values are not numbers, dc(1) will raise an error and reset (see the **RESET** section). This is a **non-portable extension**. **!\>**_r_ : Pops two values off of the stack that must be numbers and compares them. If the first value is not greater than the second (less than or equal to), then the contents of register *r* are executed. If either or both of the values are not numbers, dc(1) will raise an error and reset (see the **RESET** section). **!\>**_r_**e**_s_ : Like the above, but will execute register *s* if the comparison fails. If either or both of the values are not numbers, dc(1) will raise an error and reset (see the **RESET** section). This is a **non-portable extension**. **\<**_r_ : Pops two values off of the stack that must be numbers and compares them. If the first value is less than the second, then the contents of register *r* are executed. If either or both of the values are not numbers, dc(1) will raise an error and reset (see the **RESET** section). **\<**_r_**e**_s_ : Like the above, but will execute register *s* if the comparison fails. If either or both of the values are not numbers, dc(1) will raise an error and reset (see the **RESET** section). This is a **non-portable extension**. **!\<**_r_ : Pops two values off of the stack that must be numbers and compares them. If the first value is not less than the second (greater than or equal to), then the contents of register *r* are executed. If either or both of the values are not numbers, dc(1) will raise an error and reset (see the **RESET** section). **!\<**_r_**e**_s_ : Like the above, but will execute register *s* if the comparison fails. If either or both of the values are not numbers, dc(1) will raise an error and reset (see the **RESET** section). This is a **non-portable extension**. **=**_r_ : Pops two values off of the stack that must be numbers and compares them. If the first value is equal to the second, then the contents of register *r* are executed. If either or both of the values are not numbers, dc(1) will raise an error and reset (see the **RESET** section). **=**_r_**e**_s_ : Like the above, but will execute register *s* if the comparison fails. If either or both of the values are not numbers, dc(1) will raise an error and reset (see the **RESET** section). This is a **non-portable extension**. **!=**_r_ : Pops two values off of the stack that must be numbers and compares them. If the first value is not equal to the second, then the contents of register *r* are executed. If either or both of the values are not numbers, dc(1) will raise an error and reset (see the **RESET** section). **!=**_r_**e**_s_ : Like the above, but will execute register *s* if the comparison fails. If either or both of the values are not numbers, dc(1) will raise an error and reset (see the **RESET** section). This is a **non-portable extension**. **?** : Reads a line from the **stdin** and executes it. This is to allow macros to request input from users. **q** : During execution of a macro, this exits the execution of that macro and the execution of the macro that executed it. If there are no macros, or only one macro executing, dc(1) exits. **Q** : Pops a value from the stack which must be non-negative and is used the number of macro executions to pop off of the execution stack. If the number of levels to pop is greater than the number of executing macros, dc(1) exits. **,** : Pushes the depth of the execution stack onto the stack. The execution stack is the stack of string executions. The number that is pushed onto the stack is exactly as many as is needed to make dc(1) exit with the **Q** command, so the sequence **,Q** will make dc(1) exit. ## Status These commands query status of the stack or its top value. **Z** : Pops a value off of the stack. If it is a number, calculates the number of significant decimal digits it has and pushes the result. It will push **1** if the argument is **0** with no decimal places. If it is a string, pushes the number of characters the string has. **X** : Pops a value off of the stack. If it is a number, pushes the *scale* of the value onto the stack. If it is a string, pushes **0**. **z** : Pushes the current depth of the stack (before execution of this command) onto the stack. **y**_r_ : Pushes the current stack depth of the register *r* onto the main stack. Because each register has a depth of **1** (with the value **0** in the top item) when dc(1) starts, dc(1) requires that each register's stack must always have at least one item; dc(1) will give an error and reset otherwise (see the **RESET** section). This means that this command will never push **0**. This is a **non-portable extension**. ## Arrays These commands manipulate arrays. **:**_r_ : Pops the top two values off of the stack. The second value will be stored in the array *r* (see the **REGISTERS** section), indexed by the first value. **;**_r_ : Pops the value on top of the stack and uses it as an index into the array *r*. The selected value is then pushed onto the stack. **Y**_r_ : Pushes the length of the array *r* onto the stack. This is a **non-portable extension**. ## Global Settings These commands retrieve global settings. These are the only commands that require multiple specific characters, and all of them begin with the letter **g**. Only the characters below are allowed after the character **g**; any other character produces a parse error (see the **ERRORS** section). **gl** : Pushes the line length set by **DC_LINE_LENGTH** (see the **ENVIRONMENT VARIABLES** section) onto the stack. **gz** : Pushes **0** onto the stack if the leading zero setting has not been enabled with the **-z** or **-\-leading-zeroes** options (see the **OPTIONS** section), non-zero otherwise. # REGISTERS Registers are names that can store strings, numbers, and arrays. (Number/string registers do not interfere with array registers.) Each register is also its own stack, so the current register value is the top of the stack for the register. All registers, when first referenced, have one value (**0**) in their stack, and it is a runtime error to attempt to pop that item off of the register stack. In non-extended register mode, a register name is just the single character that follows any command that needs a register name. The only exceptions are: a newline (**'\\n'**) and a left bracket (**'['**); it is a parse error for a newline or a left bracket to be used as a register name. ## Extended Register Mode Unlike most other dc(1) implentations, this dc(1) provides nearly unlimited amounts of registers, if extended register mode is enabled. If extended register mode is enabled (**-x** or **-\-extended-register** command-line arguments are given), then normal single character registers are used *unless* the character immediately following a command that needs a register name is a space (according to **isspace()**) and not a newline (**'\\n'**). In that case, the register name is found according to the regex **\[a-z\]\[a-z0-9\_\]\*** (like bc(1) identifiers), and it is a parse error if the next non-space characters do not match that regex. # RESET When dc(1) encounters an error or a signal that it has a non-default handler for, it resets. This means that several things happen. First, any macros that are executing are stopped and popped off the stack. The behavior is not unlike that of exceptions in programming languages. Then the execution point is set so that any code waiting to execute (after all macros returned) is skipped. Thus, when dc(1) resets, it skips any remaining code waiting to be executed. Then, if it is interactive mode, and the error was not a fatal error (see the **EXIT STATUS** section), it asks for more input; otherwise, it exits with the appropriate return code. # PERFORMANCE Most dc(1) implementations use **char** types to calculate the value of **1** decimal digit at a time, but that can be slow. This dc(1) does something different. It uses large integers to calculate more than **1** decimal digit at a time. If built in a environment where **DC_LONG_BIT** (see the **LIMITS** section) is **64**, then each integer has **9** decimal digits. If built in an environment where **DC_LONG_BIT** is **32** then each integer has **4** decimal digits. This value (the number of decimal digits per large integer) is called **DC_BASE_DIGS**. In addition, this dc(1) uses an even larger integer for overflow checking. This integer type depends on the value of **DC_LONG_BIT**, but is always at least twice as large as the integer type used to store digits. # LIMITS The following are the limits on dc(1): **DC_LONG_BIT** : The number of bits in the **long** type in the environment where dc(1) was built. This determines how many decimal digits can be stored in a single large integer (see the **PERFORMANCE** section). **DC_BASE_DIGS** : The number of decimal digits per large integer (see the **PERFORMANCE** section). Depends on **DC_LONG_BIT**. **DC_BASE_POW** : The max decimal number that each large integer can store (see **DC_BASE_DIGS**) plus **1**. Depends on **DC_BASE_DIGS**. **DC_OVERFLOW_MAX** : The max number that the overflow type (see the **PERFORMANCE** section) can hold. Depends on **DC_LONG_BIT**. **DC_BASE_MAX** : The maximum output base. Set at **DC_BASE_POW**. **DC_DIM_MAX** : The maximum size of arrays. Set at **SIZE_MAX-1**. **DC_SCALE_MAX** : The maximum **scale**. Set at **DC_OVERFLOW_MAX-1**. **DC_STRING_MAX** : The maximum length of strings. Set at **DC_OVERFLOW_MAX-1**. **DC_NAME_MAX** : The maximum length of identifiers. Set at **DC_OVERFLOW_MAX-1**. **DC_NUM_MAX** : The maximum length of a number (in decimal digits), which includes digits after the decimal point. Set at **DC_OVERFLOW_MAX-1**. Exponent : The maximum allowable exponent (positive or negative). Set at **DC_OVERFLOW_MAX**. Number of vars : The maximum number of vars/arrays. Set at **SIZE_MAX-1**. These limits are meant to be effectively non-existent; the limits are so large (at least on 64-bit machines) that there should not be any point at which they become a problem. In fact, memory should be exhausted before these limits should be hit. # ENVIRONMENT VARIABLES dc(1) recognizes the following environment variables: **DC_ENV_ARGS** : This is another way to give command-line arguments to dc(1). They should be in the same format as all other command-line arguments. These are always processed first, so any files given in **DC_ENV_ARGS** will be processed before arguments and files given on the command-line. This gives the user the ability to set up "standard" options and files to be used at every invocation. The most useful thing for such files to contain would be useful functions that the user might want every time dc(1) runs. Another use would be to use the **-e** option to set **scale** to a value other than **0**. The code that parses **DC_ENV_ARGS** will correctly handle quoted arguments, but it does not understand escape sequences. For example, the string **"/home/gavin/some dc file.dc"** will be correctly parsed, but the string **"/home/gavin/some \"dc\" file.dc"** will include the backslashes. The quote parsing will handle either kind of quotes, **'** or **"**. Thus, if you have a file with any number of single quotes in the name, you can use double quotes as the outside quotes, as in **"some 'dc' file.dc"**, and vice versa if you have a file with double quotes. However, handling a file with both kinds of quotes in **DC_ENV_ARGS** is not supported due to the complexity of the parsing, though such files are still supported on the command-line where the parsing is done by the shell. **DC_LINE_LENGTH** : If this environment variable exists and contains an integer that is greater than **1** and is less than **UINT16_MAX** (**2\^16-1**), dc(1) will output lines to that length, including the backslash newline combo. The default line length is **70**. The special value of **0** will disable line length checking and print numbers without regard to line length and without backslashes and newlines. **DC_SIGINT_RESET** : If dc(1) is not in interactive mode (see the **INTERACTIVE MODE** section), then this environment variable has no effect because dc(1) exits on **SIGINT** when not in interactive mode. However, when dc(1) is in interactive mode, then if this environment variable exists and contains an integer, a non-zero value makes dc(1) reset on **SIGINT**, rather than exit, and zero makes dc(1) exit. If this environment variable exists and is *not* an integer, then dc(1) will exit on **SIGINT**. This environment variable overrides the default, which can be queried with the **-h** or **-\-help** options. **DC_TTY_MODE** : If TTY mode is *not* available (see the **TTY MODE** section), then this environment variable has no effect. However, when TTY mode is available, then if this environment variable exists and contains an integer, then a non-zero value makes dc(1) use TTY mode, and zero makes dc(1) not use TTY mode. This environment variable overrides the default, which can be queried with the **-h** or **-\-help** options. **DC_PROMPT** : If TTY mode is *not* available (see the **TTY MODE** section), then this environment variable has no effect. However, when TTY mode is available, then if this environment variable exists and contains an integer, a non-zero value makes dc(1) use a prompt, and zero or a non-integer makes dc(1) not use a prompt. If this environment variable does not exist and **DC_TTY_MODE** does, then the value of the **DC_TTY_MODE** environment variable is used. This environment variable and the **DC_TTY_MODE** environment variable override the default, which can be queried with the **-h** or **-\-help** options. +**DC_EXPR_EXIT** + +: If any expressions or expression files are given on the command-line with + **-e**, **-\-expression**, **-f**, or **-\-file**, then if this environment + variable exists and contains an integer, a non-zero value makes dc(1) exit + after executing the expressions and expression files, and a non-zero value + makes dc(1) not exit. + + This environment variable overrides the default, which can be queried with + the **-h** or **-\-help** options. + # EXIT STATUS dc(1) returns the following exit statuses: **0** : No error. **1** : A math error occurred. This follows standard practice of using **1** for expected errors, since math errors will happen in the process of normal execution. Math errors include divide by **0**, taking the square root of a negative number, attempting to convert a negative number to a hardware integer, overflow when converting a number to a hardware integer, overflow when calculating the size of a number, and attempting to use a non-integer where an integer is required. Converting to a hardware integer happens for the second operand of the power (**\^**) operator. **2** : A parse error occurred. Parse errors include unexpected **EOF**, using an invalid character, failing to find the end of a string or comment, and using a token where it is invalid. **3** : A runtime error occurred. Runtime errors include assigning an invalid number to any global (**ibase**, **obase**, or **scale**), giving a bad expression to a **read()** call, calling **read()** inside of a **read()** call, type errors (including attempting to execute a number), and attempting an operation when the stack has too few elements. **4** : A fatal error occurred. Fatal errors include memory allocation errors, I/O errors, failing to open files, attempting to use files that do not have only ASCII characters (dc(1) only accepts ASCII characters), attempting to open a directory as a file, and giving invalid command-line options. The exit status **4** is special; when a fatal error occurs, dc(1) always exits and returns **4**, no matter what mode dc(1) is in. The other statuses will only be returned when dc(1) is not in interactive mode (see the **INTERACTIVE MODE** section), since dc(1) resets its state (see the **RESET** section) and accepts more input when one of those errors occurs in interactive mode. This is also the case when interactive mode is forced by the **-i** flag or **-\-interactive** option. These exit statuses allow dc(1) to be used in shell scripting with error checking, and its normal behavior can be forced by using the **-i** flag or **-\-interactive** option. # INTERACTIVE MODE Like bc(1), dc(1) has an interactive mode and a non-interactive mode. Interactive mode is turned on automatically when both **stdin** and **stdout** are hooked to a terminal, but the **-i** flag and **-\-interactive** option can turn it on in other situations. In interactive mode, dc(1) attempts to recover from errors (see the **RESET** section), and in normal execution, flushes **stdout** as soon as execution is done for the current input. dc(1) may also reset on **SIGINT** instead of exit, depending on the contents of, or default for, the **DC_SIGINT_RESET** environment variable (see the **ENVIRONMENT VARIABLES** section). # TTY MODE If **stdin**, **stdout**, and **stderr** are all connected to a TTY, then "TTY mode" is considered to be available, and thus, dc(1) can turn on TTY mode, subject to some settings. If there is the environment variable **DC_TTY_MODE** in the environment (see the **ENVIRONMENT VARIABLES** section), then if that environment variable contains a non-zero integer, dc(1) will turn on TTY mode when **stdin**, **stdout**, and **stderr** are all connected to a TTY. If the **DC_TTY_MODE** environment variable exists but is *not* a non-zero integer, then dc(1) will not turn TTY mode on. If the environment variable **DC_TTY_MODE** does *not* exist, the default setting is used. The default setting can be queried with the **-h** or **-\-help** options. TTY mode is different from interactive mode because interactive mode is required in the [bc(1) specification][1], and interactive mode requires only **stdin** and **stdout** to be connected to a terminal. ## Command-Line History Command-line history is only enabled if TTY mode is, i.e., that **stdin**, **stdout**, and **stderr** are connected to a TTY and the **DC_TTY_MODE** environment variable (see the **ENVIRONMENT VARIABLES** section) and its default do not disable TTY mode. See the **COMMAND LINE HISTORY** section for more information. ## Prompt If TTY mode is available, then a prompt can be enabled. Like TTY mode itself, it can be turned on or off with an environment variable: **DC_PROMPT** (see the **ENVIRONMENT VARIABLES** section). If the environment variable **DC_PROMPT** exists and is a non-zero integer, then the prompt is turned on when **stdin**, **stdout**, and **stderr** are connected to a TTY and the **-P** and **-\-no-prompt** options were not used. The read prompt will be turned on under the same conditions, except that the **-R** and **-\-no-read-prompt** options must also not be used. However, if **DC_PROMPT** does not exist, the prompt can be enabled or disabled with the **DC_TTY_MODE** environment variable, the **-P** and **-\-no-prompt** options, and the **-R** and **-\-no-read-prompt** options. See the **ENVIRONMENT VARIABLES** and **OPTIONS** sections for more details. # SIGNAL HANDLING Sending a **SIGINT** will cause dc(1) to do one of two things. If dc(1) is not in interactive mode (see the **INTERACTIVE MODE** section), or the **DC_SIGINT_RESET** environment variable (see the **ENVIRONMENT VARIABLES** section), or its default, is either not an integer or it is zero, dc(1) will exit. However, if dc(1) is in interactive mode, and the **DC_SIGINT_RESET** or its default is an integer and non-zero, then dc(1) will stop executing the current input and reset (see the **RESET** section) upon receiving a **SIGINT**. Note that "current input" can mean one of two things. If dc(1) is processing input from **stdin** in interactive mode, it will ask for more input. If dc(1) is processing input from a file in interactive mode, it will stop processing the file and start processing the next file, if one exists, or ask for input from **stdin** if no other file exists. This means that if a **SIGINT** is sent to dc(1) as it is executing a file, it can seem as though dc(1) did not respond to the signal since it will immediately start executing the next file. This is by design; most files that users execute when interacting with dc(1) have function definitions, which are quick to parse. If a file takes a long time to execute, there may be a bug in that file. The rest of the files could still be executed without problem, allowing the user to continue. **SIGTERM** and **SIGQUIT** cause dc(1) to clean up and exit, and it uses the default handler for all other signals. The one exception is **SIGHUP**; in that case, and only when dc(1) is in TTY mode (see the **TTY MODE** section), a **SIGHUP** will cause dc(1) to clean up and exit. # COMMAND LINE HISTORY dc(1) supports interactive command-line editing. If dc(1) can be in TTY mode (see the **TTY MODE** section), history can be enabled. This means that command-line history can only be enabled when **stdin**, **stdout**, and **stderr** are all connected to a TTY. Like TTY mode itself, it can be turned on or off with the environment variable **DC_TTY_MODE** (see the **ENVIRONMENT VARIABLES** section). **Note**: tabs are converted to 8 spaces. # SEE ALSO bc(1) # STANDARDS The dc(1) utility operators are compliant with the operators in the bc(1) [IEEE Std 1003.1-2017 (“POSIX.1-2017”)][1] specification. # BUGS None are known. Report bugs at https://git.yzena.com/gavin/bc. # AUTHOR Gavin D. Howard and contributors. [1]: https://pubs.opengroup.org/onlinepubs/9699919799/utilities/bc.html diff --git a/contrib/bc/manuals/dc/H.1 b/contrib/bc/manuals/dc/H.1 index b4ab9f511080..f27358fb7f12 100644 --- a/contrib/bc/manuals/dc/H.1 +++ b/contrib/bc/manuals/dc/H.1 @@ -1,1523 +1,1536 @@ .\" .\" SPDX-License-Identifier: BSD-2-Clause .\" .\" Copyright (c) 2018-2021 Gavin D. Howard and contributors. .\" .\" Redistribution and use in source and binary forms, with or without .\" modification, are permitted provided that the following conditions are met: .\" .\" * Redistributions of source code must retain the above copyright notice, .\" this list of conditions and the following disclaimer. .\" .\" * Redistributions in binary form must reproduce the above copyright notice, .\" this list of conditions and the following disclaimer in the documentation .\" and/or other materials provided with the distribution. .\" .\" THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" .\" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE .\" IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE .\" ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE .\" LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR .\" CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF .\" SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS .\" INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN .\" CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) .\" ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE .\" POSSIBILITY OF SUCH DAMAGE. .\" .TH "DC" "1" "June 2021" "Gavin D. Howard" "General Commands Manual" .SH Name .PP dc - arbitrary-precision decimal reverse-Polish notation calculator .SH SYNOPSIS .PP \f[B]dc\f[R] [\f[B]-hiPRvVx\f[R]] [\f[B]--version\f[R]] [\f[B]--help\f[R]] [\f[B]--interactive\f[R]] [\f[B]--no-prompt\f[R]] [\f[B]--no-read-prompt\f[R]] [\f[B]--extended-register\f[R]] [\f[B]-e\f[R] \f[I]expr\f[R]] [\f[B]--expression\f[R]=\f[I]expr\f[R]\&...] [\f[B]-f\f[R] \f[I]file\f[R]\&...] [\f[B]--file\f[R]=\f[I]file\f[R]\&...] [\f[I]file\f[R]\&...] .SH DESCRIPTION .PP dc(1) is an arbitrary-precision calculator. It uses a stack (reverse Polish notation) to store numbers and results of computations. Arithmetic operations pop arguments off of the stack and push the results. .PP If no files are given on the command-line, then dc(1) reads from \f[B]stdin\f[R] (see the \f[B]STDIN\f[R] section). Otherwise, those files are processed, and dc(1) will then exit. .PP If a user wants to set up a standard environment, they can use \f[B]DC_ENV_ARGS\f[R] (see the \f[B]ENVIRONMENT VARIABLES\f[R] section). For example, if a user wants the \f[B]scale\f[R] always set to \f[B]10\f[R], they can set \f[B]DC_ENV_ARGS\f[R] to \f[B]-e 10k\f[R], and this dc(1) will always start with a \f[B]scale\f[R] of \f[B]10\f[R]. .SH OPTIONS .PP The following are the options that dc(1) accepts. .TP \f[B]-h\f[R], \f[B]--help\f[R] Prints a usage message and quits. .TP \f[B]-v\f[R], \f[B]-V\f[R], \f[B]--version\f[R] Print the version information (copyright header) and exit. .TP \f[B]-i\f[R], \f[B]--interactive\f[R] Forces interactive mode. (See the \f[B]INTERACTIVE MODE\f[R] section.) .RS .PP This is a \f[B]non-portable extension\f[R]. .RE .TP \f[B]-L\f[R], \f[B]--no-line-length\f[R] Disables line length checking and prints numbers without backslashes and newlines. In other words, this option sets \f[B]BC_LINE_LENGTH\f[R] to \f[B]0\f[R] (see the \f[B]ENVIRONMENT VARIABLES\f[R] section). .RS .PP This is a \f[B]non-portable extension\f[R]. .RE .TP \f[B]-P\f[R], \f[B]--no-prompt\f[R] Disables the prompt in TTY mode. (The prompt is only enabled in TTY mode. See the \f[B]TTY MODE\f[R] section.) This is mostly for those users that do not want a prompt or are not used to having them in dc(1). Most of those users would want to put this option in \f[B]DC_ENV_ARGS\f[R]. .RS .PP These options override the \f[B]DC_PROMPT\f[R] and \f[B]DC_TTY_MODE\f[R] environment variables (see the \f[B]ENVIRONMENT VARIABLES\f[R] section). .PP This is a \f[B]non-portable extension\f[R]. .RE .TP \f[B]-R\f[R], \f[B]--no-read-prompt\f[R] Disables the read prompt in TTY mode. (The read prompt is only enabled in TTY mode. See the \f[B]TTY MODE\f[R] section.) This is mostly for those users that do not want a read prompt or are not used to having them in dc(1). Most of those users would want to put this option in \f[B]BC_ENV_ARGS\f[R] (see the \f[B]ENVIRONMENT VARIABLES\f[R] section). This option is also useful in hash bang lines of dc(1) scripts that prompt for user input. .RS .PP This option does not disable the regular prompt because the read prompt is only used when the \f[B]?\f[R] command is used. .PP These options \f[I]do\f[R] override the \f[B]DC_PROMPT\f[R] and \f[B]DC_TTY_MODE\f[R] environment variables (see the \f[B]ENVIRONMENT VARIABLES\f[R] section), but only for the read prompt. .PP This is a \f[B]non-portable extension\f[R]. .RE .TP \f[B]-x\f[R] \f[B]--extended-register\f[R] Enables extended register mode. See the \f[I]Extended Register Mode\f[R] subsection of the \f[B]REGISTERS\f[R] section for more information. .RS .PP This is a \f[B]non-portable extension\f[R]. .RE .TP \f[B]-z\f[R], \f[B]--leading-zeroes\f[R] Makes bc(1) print all numbers greater than \f[B]-1\f[R] and less than \f[B]1\f[R], and not equal to \f[B]0\f[R], with a leading zero. .RS .PP This can be set for individual numbers with the \f[B]plz(x)\f[R], plznl(x)**, \f[B]pnlz(x)\f[R], and \f[B]pnlznl(x)\f[R] functions in the extended math library (see the \f[B]LIBRARY\f[R] section). .PP This is a \f[B]non-portable extension\f[R]. .RE .TP \f[B]-e\f[R] \f[I]expr\f[R], \f[B]--expression\f[R]=\f[I]expr\f[R] Evaluates \f[I]expr\f[R]. If multiple expressions are given, they are evaluated in order. If files are given as well (see below), the expressions and files are evaluated in the order given. This means that if a file is given before an expression, the file is read in and evaluated first. .RS .PP If this option is given on the command-line (i.e., not in \f[B]DC_ENV_ARGS\f[R], see the \f[B]ENVIRONMENT VARIABLES\f[R] section), then after processing all expressions and files, dc(1) will exit, unless \f[B]-\f[R] (\f[B]stdin\f[R]) was given as an argument at least once to \f[B]-f\f[R] or \f[B]--file\f[R], whether on the command-line or in \f[B]DC_ENV_ARGS\f[R]. However, if any other \f[B]-e\f[R], \f[B]--expression\f[R], \f[B]-f\f[R], or \f[B]--file\f[R] arguments are given after \f[B]-f-\f[R] or equivalent is given, dc(1) will give a fatal error and exit. .PP This is a \f[B]non-portable extension\f[R]. .RE .TP \f[B]-f\f[R] \f[I]file\f[R], \f[B]--file\f[R]=\f[I]file\f[R] Reads in \f[I]file\f[R] and evaluates it, line by line, as though it were read through \f[B]stdin\f[R]. If expressions are also given (see above), the expressions are evaluated in the order given. .RS .PP If this option is given on the command-line (i.e., not in \f[B]DC_ENV_ARGS\f[R], see the \f[B]ENVIRONMENT VARIABLES\f[R] section), then after processing all expressions and files, dc(1) will exit, unless \f[B]-\f[R] (\f[B]stdin\f[R]) was given as an argument at least once to \f[B]-f\f[R] or \f[B]--file\f[R]. However, if any other \f[B]-e\f[R], \f[B]--expression\f[R], \f[B]-f\f[R], or \f[B]--file\f[R] arguments are given after \f[B]-f-\f[R] or equivalent is given, dc(1) will give a fatal error and exit. .PP This is a \f[B]non-portable extension\f[R]. .RE .PP All long options are \f[B]non-portable extensions\f[R]. .SH STDIN .PP If no files are given on the command-line and no files or expressions are given by the \f[B]-f\f[R], \f[B]--file\f[R], \f[B]-e\f[R], or \f[B]--expression\f[R] options, then dc(1) read from \f[B]stdin\f[R]. .PP However, there is a caveat to this. .PP First, \f[B]stdin\f[R] is evaluated a line at a time. The only exception to this is if a string has been finished, but not ended. This means that, except for escaped brackets, all brackets must be balanced before dc(1) parses and executes. .SH STDOUT .PP Any non-error output is written to \f[B]stdout\f[R]. In addition, if history (see the \f[B]HISTORY\f[R] section) and the prompt (see the \f[B]TTY MODE\f[R] section) are enabled, both are output to \f[B]stdout\f[R]. .PP \f[B]Note\f[R]: Unlike other dc(1) implementations, this dc(1) will issue a fatal error (see the \f[B]EXIT STATUS\f[R] section) if it cannot write to \f[B]stdout\f[R], so if \f[B]stdout\f[R] is closed, as in \f[B]dc >&-\f[R], it will quit with an error. This is done so that dc(1) can report problems when \f[B]stdout\f[R] is redirected to a file. .PP If there are scripts that depend on the behavior of other dc(1) implementations, it is recommended that those scripts be changed to redirect \f[B]stdout\f[R] to \f[B]/dev/null\f[R]. .SH STDERR .PP Any error output is written to \f[B]stderr\f[R]. .PP \f[B]Note\f[R]: Unlike other dc(1) implementations, this dc(1) will issue a fatal error (see the \f[B]EXIT STATUS\f[R] section) if it cannot write to \f[B]stderr\f[R], so if \f[B]stderr\f[R] is closed, as in \f[B]dc 2>&-\f[R], it will quit with an error. This is done so that dc(1) can exit with an error code when \f[B]stderr\f[R] is redirected to a file. .PP If there are scripts that depend on the behavior of other dc(1) implementations, it is recommended that those scripts be changed to redirect \f[B]stderr\f[R] to \f[B]/dev/null\f[R]. .SH SYNTAX .PP Each item in the input source code, either a number (see the \f[B]NUMBERS\f[R] section) or a command (see the \f[B]COMMANDS\f[R] section), is processed and executed, in order. Input is processed immediately when entered. .PP \f[B]ibase\f[R] is a register (see the \f[B]REGISTERS\f[R] section) that determines how to interpret constant numbers. It is the \[lq]input\[rq] base, or the number base used for interpreting input numbers. \f[B]ibase\f[R] is initially \f[B]10\f[R]. The max allowable value for \f[B]ibase\f[R] is \f[B]16\f[R]. The min allowable value for \f[B]ibase\f[R] is \f[B]2\f[R]. The max allowable value for \f[B]ibase\f[R] can be queried in dc(1) programs with the \f[B]T\f[R] command. .PP \f[B]obase\f[R] is a register (see the \f[B]REGISTERS\f[R] section) that determines how to output results. It is the \[lq]output\[rq] base, or the number base used for outputting numbers. \f[B]obase\f[R] is initially \f[B]10\f[R]. The max allowable value for \f[B]obase\f[R] is \f[B]DC_BASE_MAX\f[R] and can be queried with the \f[B]U\f[R] command. The min allowable value for \f[B]obase\f[R] is \f[B]0\f[R]. If \f[B]obase\f[R] is \f[B]0\f[R], values are output in scientific notation, and if \f[B]obase\f[R] is \f[B]1\f[R], values are output in engineering notation. Otherwise, values are output in the specified base. .PP Outputting in scientific and engineering notations are \f[B]non-portable extensions\f[R]. .PP The \f[I]scale\f[R] of an expression is the number of digits in the result of the expression right of the decimal point, and \f[B]scale\f[R] is a register (see the \f[B]REGISTERS\f[R] section) that sets the precision of any operations (with exceptions). \f[B]scale\f[R] is initially \f[B]0\f[R]. \f[B]scale\f[R] cannot be negative. The max allowable value for \f[B]scale\f[R] can be queried in dc(1) programs with the \f[B]V\f[R] command. .PP \f[B]seed\f[R] is a register containing the current seed for the pseudo-random number generator. If the current value of \f[B]seed\f[R] is queried and stored, then if it is assigned to \f[B]seed\f[R] later, the pseudo-random number generator is guaranteed to produce the same sequence of pseudo-random numbers that were generated after the value of \f[B]seed\f[R] was first queried. .PP Multiple values assigned to \f[B]seed\f[R] can produce the same sequence of pseudo-random numbers. Likewise, when a value is assigned to \f[B]seed\f[R], it is not guaranteed that querying \f[B]seed\f[R] immediately after will return the same value. In addition, the value of \f[B]seed\f[R] will change after any call to the \f[B]\[cq]\f[R] command or the \f[B]\[lq]\f[R] command that does not get receive a value of \f[B]0\f[R] or \f[B]1\f[R]. The maximum integer returned by the \f[B]\[cq]\f[R] command can be queried with the \f[B]W\f[R] command. .PP \f[B]Note\f[R]: The values returned by the pseudo-random number generator with the \f[B]\[cq]\f[R] and \f[B]\[lq]\f[R] commands are guaranteed to \f[B]NOT\f[R] be cryptographically secure. This is a consequence of using a seeded pseudo-random number generator. However, they \f[I]are\f[R] guaranteed to be reproducible with identical \f[B]seed\f[R] values. This means that the pseudo-random values from dc(1) should only be used where a reproducible stream of pseudo-random numbers is \f[I]ESSENTIAL\f[R]. In any other case, use a non-seeded pseudo-random number generator. .PP The pseudo-random number generator, \f[B]seed\f[R], and all associated operations are \f[B]non-portable extensions\f[R]. .SS Comments .PP Comments go from \f[B]#\f[R] until, and not including, the next newline. This is a \f[B]non-portable extension\f[R]. .SH NUMBERS .PP Numbers are strings made up of digits, uppercase letters up to \f[B]F\f[R], and at most \f[B]1\f[R] period for a radix. Numbers can have up to \f[B]DC_NUM_MAX\f[R] digits. Uppercase letters are equal to \f[B]9\f[R] + their position in the alphabet (i.e., \f[B]A\f[R] equals \f[B]10\f[R], or \f[B]9+1\f[R]). If a digit or letter makes no sense with the current value of \f[B]ibase\f[R], they are set to the value of the highest valid digit in \f[B]ibase\f[R]. .PP Single-character numbers (i.e., \f[B]A\f[R] alone) take the value that they would have if they were valid digits, regardless of the value of \f[B]ibase\f[R]. This means that \f[B]A\f[R] alone always equals decimal \f[B]10\f[R] and \f[B]F\f[R] alone always equals decimal \f[B]15\f[R]. .PP In addition, dc(1) accepts numbers in scientific notation. These have the form \f[B]e\f[R]. The exponent (the portion after the \f[B]e\f[R]) must be an integer. An example is \f[B]1.89237e9\f[R], which is equal to \f[B]1892370000\f[R]. Negative exponents are also allowed, so \f[B]4.2890e_3\f[R] is equal to \f[B]0.0042890\f[R]. .PP \f[B]WARNING\f[R]: Both the number and the exponent in scientific notation are interpreted according to the current \f[B]ibase\f[R], but the number is still multiplied by \f[B]10\[ha]exponent\f[R] regardless of the current \f[B]ibase\f[R]. For example, if \f[B]ibase\f[R] is \f[B]16\f[R] and dc(1) is given the number string \f[B]FFeA\f[R], the resulting decimal number will be \f[B]2550000000000\f[R], and if dc(1) is given the number string \f[B]10e_4\f[R], the resulting decimal number will be \f[B]0.0016\f[R]. .PP Accepting input as scientific notation is a \f[B]non-portable extension\f[R]. .SH COMMANDS .PP The valid commands are listed below. .SS Printing .PP These commands are used for printing. .PP Note that both scientific notation and engineering notation are available for printing numbers. Scientific notation is activated by assigning \f[B]0\f[R] to \f[B]obase\f[R] using \f[B]0o\f[R], and engineering notation is activated by assigning \f[B]1\f[R] to \f[B]obase\f[R] using \f[B]1o\f[R]. To deactivate them, just assign a different value to \f[B]obase\f[R]. .PP Printing numbers in scientific notation and/or engineering notation is a \f[B]non-portable extension\f[R]. .TP \f[B]p\f[R] Prints the value on top of the stack, whether number or string, and prints a newline after. .RS .PP This does not alter the stack. .RE .TP \f[B]n\f[R] Prints the value on top of the stack, whether number or string, and pops it off of the stack. .TP \f[B]P\f[R] Pops a value off the stack. .RS .PP If the value is a number, it is truncated and the absolute value of the result is printed as though \f[B]obase\f[R] is \f[B]256\f[R] and each digit is interpreted as an 8-bit ASCII character, making it a byte stream. .PP If the value is a string, it is printed without a trailing newline. .PP This is a \f[B]non-portable extension\f[R]. .RE .TP \f[B]f\f[R] Prints the entire contents of the stack, in order from newest to oldest, without altering anything. .RS .PP Users should use this command when they get lost. .RE .SS Arithmetic .PP These are the commands used for arithmetic. .TP \f[B]+\f[R] The top two values are popped off the stack, added, and the result is pushed onto the stack. The \f[I]scale\f[R] of the result is equal to the max \f[I]scale\f[R] of both operands. .TP \f[B]-\f[R] The top two values are popped off the stack, subtracted, and the result is pushed onto the stack. The \f[I]scale\f[R] of the result is equal to the max \f[I]scale\f[R] of both operands. .TP \f[B]*\f[R] The top two values are popped off the stack, multiplied, and the result is pushed onto the stack. If \f[B]a\f[R] is the \f[I]scale\f[R] of the first expression and \f[B]b\f[R] is the \f[I]scale\f[R] of the second expression, the \f[I]scale\f[R] of the result is equal to \f[B]min(a+b,max(scale,a,b))\f[R] where \f[B]min()\f[R] and \f[B]max()\f[R] return the obvious values. .TP \f[B]/\f[R] The top two values are popped off the stack, divided, and the result is pushed onto the stack. The \f[I]scale\f[R] of the result is equal to \f[B]scale\f[R]. .RS .PP The first value popped off of the stack must be non-zero. .RE .TP \f[B]%\f[R] The top two values are popped off the stack, remaindered, and the result is pushed onto the stack. .RS .PP Remaindering is equivalent to 1) Computing \f[B]a/b\f[R] to current \f[B]scale\f[R], and 2) Using the result of step 1 to calculate \f[B]a-(a/b)*b\f[R] to \f[I]scale\f[R] \f[B]max(scale+scale(b),scale(a))\f[R]. .PP The first value popped off of the stack must be non-zero. .RE .TP \f[B]\[ti]\f[R] The top two values are popped off the stack, divided and remaindered, and the results (divided first, remainder second) are pushed onto the stack. This is equivalent to \f[B]x y / x y %\f[R] except that \f[B]x\f[R] and \f[B]y\f[R] are only evaluated once. .RS .PP The first value popped off of the stack must be non-zero. .PP This is a \f[B]non-portable extension\f[R]. .RE .TP \f[B]\[ha]\f[R] The top two values are popped off the stack, the second is raised to the power of the first, and the result is pushed onto the stack. The \f[I]scale\f[R] of the result is equal to \f[B]scale\f[R]. .RS .PP The first value popped off of the stack must be an integer, and if that value is negative, the second value popped off of the stack must be non-zero. .RE .TP \f[B]v\f[R] The top value is popped off the stack, its square root is computed, and the result is pushed onto the stack. The \f[I]scale\f[R] of the result is equal to \f[B]scale\f[R]. .RS .PP The value popped off of the stack must be non-negative. .RE .TP \f[B]_\f[R] If this command \f[I]immediately\f[R] precedes a number (i.e., no spaces or other commands), then that number is input as a negative number. .RS .PP Otherwise, the top value on the stack is popped and copied, and the copy is negated and pushed onto the stack. This behavior without a number is a \f[B]non-portable extension\f[R]. .RE .TP \f[B]b\f[R] The top value is popped off the stack, and if it is zero, it is pushed back onto the stack. Otherwise, its absolute value is pushed onto the stack. .RS .PP This is a \f[B]non-portable extension\f[R]. .RE .TP \f[B]|\f[R] The top three values are popped off the stack, a modular exponentiation is computed, and the result is pushed onto the stack. .RS .PP The first value popped is used as the reduction modulus and must be an integer and non-zero. The second value popped is used as the exponent and must be an integer and non-negative. The third value popped is the base and must be an integer. .PP This is a \f[B]non-portable extension\f[R]. .RE .TP \f[B]$\f[R] The top value is popped off the stack and copied, and the copy is truncated and pushed onto the stack. .RS .PP This is a \f[B]non-portable extension\f[R]. .RE .TP \f[B]\[at]\f[R] The top two values are popped off the stack, and the precision of the second is set to the value of the first, whether by truncation or extension. .RS .PP The first value popped off of the stack must be an integer and non-negative. .PP This is a \f[B]non-portable extension\f[R]. .RE .TP \f[B]H\f[R] The top two values are popped off the stack, and the second is shifted left (radix shifted right) to the value of the first. .RS .PP The first value popped off of the stack must be an integer and non-negative. .PP This is a \f[B]non-portable extension\f[R]. .RE .TP \f[B]h\f[R] The top two values are popped off the stack, and the second is shifted right (radix shifted left) to the value of the first. .RS .PP The first value popped off of the stack must be an integer and non-negative. .PP This is a \f[B]non-portable extension\f[R]. .RE .TP \f[B]G\f[R] The top two values are popped off of the stack, they are compared, and a \f[B]1\f[R] is pushed if they are equal, or \f[B]0\f[R] otherwise. .RS .PP This is a \f[B]non-portable extension\f[R]. .RE .TP \f[B]N\f[R] The top value is popped off of the stack, and if it a \f[B]0\f[R], a \f[B]1\f[R] is pushed; otherwise, a \f[B]0\f[R] is pushed. .RS .PP This is a \f[B]non-portable extension\f[R]. .RE .TP \f[B](\f[R] The top two values are popped off of the stack, they are compared, and a \f[B]1\f[R] is pushed if the first is less than the second, or \f[B]0\f[R] otherwise. .RS .PP This is a \f[B]non-portable extension\f[R]. .RE .TP \f[B]{\f[R] The top two values are popped off of the stack, they are compared, and a \f[B]1\f[R] is pushed if the first is less than or equal to the second, or \f[B]0\f[R] otherwise. .RS .PP This is a \f[B]non-portable extension\f[R]. .RE .TP \f[B])\f[R] The top two values are popped off of the stack, they are compared, and a \f[B]1\f[R] is pushed if the first is greater than the second, or \f[B]0\f[R] otherwise. .RS .PP This is a \f[B]non-portable extension\f[R]. .RE .TP \f[B]}\f[R] The top two values are popped off of the stack, they are compared, and a \f[B]1\f[R] is pushed if the first is greater than or equal to the second, or \f[B]0\f[R] otherwise. .RS .PP This is a \f[B]non-portable extension\f[R]. .RE .TP \f[B]M\f[R] The top two values are popped off of the stack. If they are both non-zero, a \f[B]1\f[R] is pushed onto the stack. If either of them is zero, or both of them are, then a \f[B]0\f[R] is pushed onto the stack. .RS .PP This is like the \f[B]&&\f[R] operator in bc(1), and it is \f[I]not\f[R] a short-circuit operator. .PP This is a \f[B]non-portable extension\f[R]. .RE .TP \f[B]m\f[R] The top two values are popped off of the stack. If at least one of them is non-zero, a \f[B]1\f[R] is pushed onto the stack. If both of them are zero, then a \f[B]0\f[R] is pushed onto the stack. .RS .PP This is like the \f[B]||\f[R] operator in bc(1), and it is \f[I]not\f[R] a short-circuit operator. .PP This is a \f[B]non-portable extension\f[R]. .RE .SS Pseudo-Random Number Generator .PP dc(1) has a built-in pseudo-random number generator. These commands query the pseudo-random number generator. (See Parameters for more information about the \f[B]seed\f[R] value that controls the pseudo-random number generator.) .PP The pseudo-random number generator is guaranteed to \f[B]NOT\f[R] be cryptographically secure. .TP \f[B]\[cq]\f[R] Generates an integer between 0 and \f[B]DC_RAND_MAX\f[R], inclusive (see the \f[B]LIMITS\f[R] section). .RS .PP The generated integer is made as unbiased as possible, subject to the limitations of the pseudo-random number generator. .PP This is a \f[B]non-portable extension\f[R]. .RE .TP \f[B]\[lq]\f[R] Pops a value off of the stack, which is used as an \f[B]exclusive\f[R] upper bound on the integer that will be generated. If the bound is negative or is a non-integer, an error is raised, and dc(1) resets (see the \f[B]RESET\f[R] section) while \f[B]seed\f[R] remains unchanged. If the bound is larger than \f[B]DC_RAND_MAX\f[R], the higher bound is honored by generating several pseudo-random integers, multiplying them by appropriate powers of \f[B]DC_RAND_MAX+1\f[R], and adding them together. Thus, the size of integer that can be generated with this command is unbounded. Using this command will change the value of \f[B]seed\f[R], unless the operand is \f[B]0\f[R] or \f[B]1\f[R]. In that case, \f[B]0\f[R] is pushed onto the stack, and \f[B]seed\f[R] is \f[I]not\f[R] changed. .RS .PP The generated integer is made as unbiased as possible, subject to the limitations of the pseudo-random number generator. .PP This is a \f[B]non-portable extension\f[R]. .RE .SS Stack Control .PP These commands control the stack. .TP \f[B]c\f[R] Removes all items from (\[lq]clears\[rq]) the stack. .TP \f[B]d\f[R] Copies the item on top of the stack (\[lq]duplicates\[rq]) and pushes the copy onto the stack. .TP \f[B]r\f[R] Swaps (\[lq]reverses\[rq]) the two top items on the stack. .TP \f[B]R\f[R] Pops (\[lq]removes\[rq]) the top value from the stack. .SS Register Control .PP These commands control registers (see the \f[B]REGISTERS\f[R] section). .TP \f[B]s\f[R]\f[I]r\f[R] Pops the value off the top of the stack and stores it into register \f[I]r\f[R]. .TP \f[B]l\f[R]\f[I]r\f[R] Copies the value in register \f[I]r\f[R] and pushes it onto the stack. This does not alter the contents of \f[I]r\f[R]. .TP \f[B]S\f[R]\f[I]r\f[R] Pops the value off the top of the (main) stack and pushes it onto the stack of register \f[I]r\f[R]. The previous value of the register becomes inaccessible. .TP \f[B]L\f[R]\f[I]r\f[R] Pops the value off the top of the stack for register \f[I]r\f[R] and push it onto the main stack. The previous value in the stack for register \f[I]r\f[R], if any, is now accessible via the \f[B]l\f[R]\f[I]r\f[R] command. .SS Parameters .PP These commands control the values of \f[B]ibase\f[R], \f[B]obase\f[R], \f[B]scale\f[R], and \f[B]seed\f[R]. Also see the \f[B]SYNTAX\f[R] section. .TP \f[B]i\f[R] Pops the value off of the top of the stack and uses it to set \f[B]ibase\f[R], which must be between \f[B]2\f[R] and \f[B]16\f[R], inclusive. .RS .PP If the value on top of the stack has any \f[I]scale\f[R], the \f[I]scale\f[R] is ignored. .RE .TP \f[B]o\f[R] Pops the value off of the top of the stack and uses it to set \f[B]obase\f[R], which must be between \f[B]0\f[R] and \f[B]DC_BASE_MAX\f[R], inclusive (see the \f[B]LIMITS\f[R] section and the \f[B]NUMBERS\f[R] section). .RS .PP If the value on top of the stack has any \f[I]scale\f[R], the \f[I]scale\f[R] is ignored. .RE .TP \f[B]k\f[R] Pops the value off of the top of the stack and uses it to set \f[B]scale\f[R], which must be non-negative. .RS .PP If the value on top of the stack has any \f[I]scale\f[R], the \f[I]scale\f[R] is ignored. .RE .TP \f[B]j\f[R] Pops the value off of the top of the stack and uses it to set \f[B]seed\f[R]. The meaning of \f[B]seed\f[R] is dependent on the current pseudo-random number generator but is guaranteed to not change except for new major versions. .RS .PP The \f[I]scale\f[R] and sign of the value may be significant. .PP If a previously used \f[B]seed\f[R] value is used again, the pseudo-random number generator is guaranteed to produce the same sequence of pseudo-random numbers as it did when the \f[B]seed\f[R] value was previously used. .PP The exact value assigned to \f[B]seed\f[R] is not guaranteed to be returned if the \f[B]J\f[R] command is used. However, if \f[B]seed\f[R] \f[I]does\f[R] return a different value, both values, when assigned to \f[B]seed\f[R], are guaranteed to produce the same sequence of pseudo-random numbers. This means that certain values assigned to \f[B]seed\f[R] will not produce unique sequences of pseudo-random numbers. .PP There is no limit to the length (number of significant decimal digits) or \f[I]scale\f[R] of the value that can be assigned to \f[B]seed\f[R]. .PP This is a \f[B]non-portable extension\f[R]. .RE .TP \f[B]I\f[R] Pushes the current value of \f[B]ibase\f[R] onto the main stack. .TP \f[B]O\f[R] Pushes the current value of \f[B]obase\f[R] onto the main stack. .TP \f[B]K\f[R] Pushes the current value of \f[B]scale\f[R] onto the main stack. .TP \f[B]J\f[R] Pushes the current value of \f[B]seed\f[R] onto the main stack. .RS .PP This is a \f[B]non-portable extension\f[R]. .RE .TP \f[B]T\f[R] Pushes the maximum allowable value of \f[B]ibase\f[R] onto the main stack. .RS .PP This is a \f[B]non-portable extension\f[R]. .RE .TP \f[B]U\f[R] Pushes the maximum allowable value of \f[B]obase\f[R] onto the main stack. .RS .PP This is a \f[B]non-portable extension\f[R]. .RE .TP \f[B]V\f[R] Pushes the maximum allowable value of \f[B]scale\f[R] onto the main stack. .RS .PP This is a \f[B]non-portable extension\f[R]. .RE .TP \f[B]W\f[R] Pushes the maximum (inclusive) integer that can be generated with the \f[B]\[cq]\f[R] pseudo-random number generator command. .RS .PP This is a \f[B]non-portable extension\f[R]. .RE .SS Strings .PP The following commands control strings. .PP dc(1) can work with both numbers and strings, and registers (see the \f[B]REGISTERS\f[R] section) can hold both strings and numbers. dc(1) always knows whether the contents of a register are a string or a number. .PP While arithmetic operations have to have numbers, and will print an error if given a string, other commands accept strings. .PP Strings can also be executed as macros. For example, if the string \f[B][1pR]\f[R] is executed as a macro, then the code \f[B]1pR\f[R] is executed, meaning that the \f[B]1\f[R] will be printed with a newline after and then popped from the stack. .TP \f[B][\f[R]\f[I]characters\f[R]\f[B]]\f[R] Makes a string containing \f[I]characters\f[R] and pushes it onto the stack. .RS .PP If there are brackets (\f[B][\f[R] and \f[B]]\f[R]) in the string, then they must be balanced. Unbalanced brackets can be escaped using a backslash (\f[B]\[rs]\f[R]) character. .PP If there is a backslash character in the string, the character after it (even another backslash) is put into the string verbatim, but the (first) backslash is not. .RE .TP \f[B]a\f[R] The value on top of the stack is popped. .RS .PP If it is a number, it is truncated and its absolute value is taken. The result mod \f[B]256\f[R] is calculated. If that result is \f[B]0\f[R], push an empty string; otherwise, push a one-character string where the character is the result of the mod interpreted as an ASCII character. .PP If it is a string, then a new string is made. If the original string is empty, the new string is empty. If it is not, then the first character of the original string is used to create the new string as a one-character string. The new string is then pushed onto the stack. .PP This is a \f[B]non-portable extension\f[R]. .RE .TP \f[B]x\f[R] Pops a value off of the top of the stack. .RS .PP If it is a number, it is pushed back onto the stack. .PP If it is a string, it is executed as a macro. .PP This behavior is the norm whenever a macro is executed, whether by this command or by the conditional execution commands below. .RE .TP \f[B]>\f[R]\f[I]r\f[R] Pops two values off of the stack that must be numbers and compares them. If the first value is greater than the second, then the contents of register \f[I]r\f[R] are executed. .RS .PP For example, \f[B]0 1>a\f[R] will execute the contents of register \f[B]a\f[R], and \f[B]1 0>a\f[R] will not. .PP If either or both of the values are not numbers, dc(1) will raise an error and reset (see the \f[B]RESET\f[R] section). .RE .TP \f[B]>\f[R]\f[I]r\f[R]\f[B]e\f[R]\f[I]s\f[R] Like the above, but will execute register \f[I]s\f[R] if the comparison fails. .RS .PP If either or both of the values are not numbers, dc(1) will raise an error and reset (see the \f[B]RESET\f[R] section). .PP This is a \f[B]non-portable extension\f[R]. .RE .TP \f[B]!>\f[R]\f[I]r\f[R] Pops two values off of the stack that must be numbers and compares them. If the first value is not greater than the second (less than or equal to), then the contents of register \f[I]r\f[R] are executed. .RS .PP If either or both of the values are not numbers, dc(1) will raise an error and reset (see the \f[B]RESET\f[R] section). .RE .TP \f[B]!>\f[R]\f[I]r\f[R]\f[B]e\f[R]\f[I]s\f[R] Like the above, but will execute register \f[I]s\f[R] if the comparison fails. .RS .PP If either or both of the values are not numbers, dc(1) will raise an error and reset (see the \f[B]RESET\f[R] section). .PP This is a \f[B]non-portable extension\f[R]. .RE .TP \f[B]<\f[R]\f[I]r\f[R] Pops two values off of the stack that must be numbers and compares them. If the first value is less than the second, then the contents of register \f[I]r\f[R] are executed. .RS .PP If either or both of the values are not numbers, dc(1) will raise an error and reset (see the \f[B]RESET\f[R] section). .RE .TP \f[B]<\f[R]\f[I]r\f[R]\f[B]e\f[R]\f[I]s\f[R] Like the above, but will execute register \f[I]s\f[R] if the comparison fails. .RS .PP If either or both of the values are not numbers, dc(1) will raise an error and reset (see the \f[B]RESET\f[R] section). .PP This is a \f[B]non-portable extension\f[R]. .RE .TP \f[B]!<\f[R]\f[I]r\f[R] Pops two values off of the stack that must be numbers and compares them. If the first value is not less than the second (greater than or equal to), then the contents of register \f[I]r\f[R] are executed. .RS .PP If either or both of the values are not numbers, dc(1) will raise an error and reset (see the \f[B]RESET\f[R] section). .RE .TP \f[B]!<\f[R]\f[I]r\f[R]\f[B]e\f[R]\f[I]s\f[R] Like the above, but will execute register \f[I]s\f[R] if the comparison fails. .RS .PP If either or both of the values are not numbers, dc(1) will raise an error and reset (see the \f[B]RESET\f[R] section). .PP This is a \f[B]non-portable extension\f[R]. .RE .TP \f[B]=\f[R]\f[I]r\f[R] Pops two values off of the stack that must be numbers and compares them. If the first value is equal to the second, then the contents of register \f[I]r\f[R] are executed. .RS .PP If either or both of the values are not numbers, dc(1) will raise an error and reset (see the \f[B]RESET\f[R] section). .RE .TP \f[B]=\f[R]\f[I]r\f[R]\f[B]e\f[R]\f[I]s\f[R] Like the above, but will execute register \f[I]s\f[R] if the comparison fails. .RS .PP If either or both of the values are not numbers, dc(1) will raise an error and reset (see the \f[B]RESET\f[R] section). .PP This is a \f[B]non-portable extension\f[R]. .RE .TP \f[B]!=\f[R]\f[I]r\f[R] Pops two values off of the stack that must be numbers and compares them. If the first value is not equal to the second, then the contents of register \f[I]r\f[R] are executed. .RS .PP If either or both of the values are not numbers, dc(1) will raise an error and reset (see the \f[B]RESET\f[R] section). .RE .TP \f[B]!=\f[R]\f[I]r\f[R]\f[B]e\f[R]\f[I]s\f[R] Like the above, but will execute register \f[I]s\f[R] if the comparison fails. .RS .PP If either or both of the values are not numbers, dc(1) will raise an error and reset (see the \f[B]RESET\f[R] section). .PP This is a \f[B]non-portable extension\f[R]. .RE .TP \f[B]?\f[R] Reads a line from the \f[B]stdin\f[R] and executes it. This is to allow macros to request input from users. .TP \f[B]q\f[R] During execution of a macro, this exits the execution of that macro and the execution of the macro that executed it. If there are no macros, or only one macro executing, dc(1) exits. .TP \f[B]Q\f[R] Pops a value from the stack which must be non-negative and is used the number of macro executions to pop off of the execution stack. If the number of levels to pop is greater than the number of executing macros, dc(1) exits. .TP \f[B],\f[R] Pushes the depth of the execution stack onto the stack. The execution stack is the stack of string executions. The number that is pushed onto the stack is exactly as many as is needed to make dc(1) exit with the \f[B]Q\f[R] command, so the sequence \f[B],Q\f[R] will make dc(1) exit. .SS Status .PP These commands query status of the stack or its top value. .TP \f[B]Z\f[R] Pops a value off of the stack. .RS .PP If it is a number, calculates the number of significant decimal digits it has and pushes the result. It will push \f[B]1\f[R] if the argument is \f[B]0\f[R] with no decimal places. .PP If it is a string, pushes the number of characters the string has. .RE .TP \f[B]X\f[R] Pops a value off of the stack. .RS .PP If it is a number, pushes the \f[I]scale\f[R] of the value onto the stack. .PP If it is a string, pushes \f[B]0\f[R]. .RE .TP \f[B]z\f[R] Pushes the current depth of the stack (before execution of this command) onto the stack. .TP \f[B]y\f[R]\f[I]r\f[R] Pushes the current stack depth of the register \f[I]r\f[R] onto the main stack. .RS .PP Because each register has a depth of \f[B]1\f[R] (with the value \f[B]0\f[R] in the top item) when dc(1) starts, dc(1) requires that each register\[cq]s stack must always have at least one item; dc(1) will give an error and reset otherwise (see the \f[B]RESET\f[R] section). This means that this command will never push \f[B]0\f[R]. .PP This is a \f[B]non-portable extension\f[R]. .RE .SS Arrays .PP These commands manipulate arrays. .TP \f[B]:\f[R]\f[I]r\f[R] Pops the top two values off of the stack. The second value will be stored in the array \f[I]r\f[R] (see the \f[B]REGISTERS\f[R] section), indexed by the first value. .TP \f[B];\f[R]\f[I]r\f[R] Pops the value on top of the stack and uses it as an index into the array \f[I]r\f[R]. The selected value is then pushed onto the stack. .TP \f[B]Y\f[R]\f[I]r\f[R] Pushes the length of the array \f[I]r\f[R] onto the stack. .RS .PP This is a \f[B]non-portable extension\f[R]. .RE .SS Global Settings .PP These commands retrieve global settings. These are the only commands that require multiple specific characters, and all of them begin with the letter \f[B]g\f[R]. Only the characters below are allowed after the character \f[B]g\f[R]; any other character produces a parse error (see the \f[B]ERRORS\f[R] section). .TP \f[B]gl\f[R] Pushes the line length set by \f[B]DC_LINE_LENGTH\f[R] (see the \f[B]ENVIRONMENT VARIABLES\f[R] section) onto the stack. .TP \f[B]gz\f[R] Pushes \f[B]0\f[R] onto the stack if the leading zero setting has not been enabled with the \f[B]-z\f[R] or \f[B]--leading-zeroes\f[R] options (see the \f[B]OPTIONS\f[R] section), non-zero otherwise. .SH REGISTERS .PP Registers are names that can store strings, numbers, and arrays. (Number/string registers do not interfere with array registers.) .PP Each register is also its own stack, so the current register value is the top of the stack for the register. All registers, when first referenced, have one value (\f[B]0\f[R]) in their stack, and it is a runtime error to attempt to pop that item off of the register stack. .PP In non-extended register mode, a register name is just the single character that follows any command that needs a register name. The only exceptions are: a newline (\f[B]`\[rs]n'\f[R]) and a left bracket (\f[B]`['\f[R]); it is a parse error for a newline or a left bracket to be used as a register name. .SS Extended Register Mode .PP Unlike most other dc(1) implentations, this dc(1) provides nearly unlimited amounts of registers, if extended register mode is enabled. .PP If extended register mode is enabled (\f[B]-x\f[R] or \f[B]--extended-register\f[R] command-line arguments are given), then normal single character registers are used \f[I]unless\f[R] the character immediately following a command that needs a register name is a space (according to \f[B]isspace()\f[R]) and not a newline (\f[B]`\[rs]n'\f[R]). .PP In that case, the register name is found according to the regex \f[B][a-z][a-z0-9_]*\f[R] (like bc(1) identifiers), and it is a parse error if the next non-space characters do not match that regex. .SH RESET .PP When dc(1) encounters an error or a signal that it has a non-default handler for, it resets. This means that several things happen. .PP First, any macros that are executing are stopped and popped off the stack. The behavior is not unlike that of exceptions in programming languages. Then the execution point is set so that any code waiting to execute (after all macros returned) is skipped. .PP Thus, when dc(1) resets, it skips any remaining code waiting to be executed. Then, if it is interactive mode, and the error was not a fatal error (see the \f[B]EXIT STATUS\f[R] section), it asks for more input; otherwise, it exits with the appropriate return code. .SH PERFORMANCE .PP Most dc(1) implementations use \f[B]char\f[R] types to calculate the value of \f[B]1\f[R] decimal digit at a time, but that can be slow. This dc(1) does something different. .PP It uses large integers to calculate more than \f[B]1\f[R] decimal digit at a time. If built in a environment where \f[B]DC_LONG_BIT\f[R] (see the \f[B]LIMITS\f[R] section) is \f[B]64\f[R], then each integer has \f[B]9\f[R] decimal digits. If built in an environment where \f[B]DC_LONG_BIT\f[R] is \f[B]32\f[R] then each integer has \f[B]4\f[R] decimal digits. This value (the number of decimal digits per large integer) is called \f[B]DC_BASE_DIGS\f[R]. .PP In addition, this dc(1) uses an even larger integer for overflow checking. This integer type depends on the value of \f[B]DC_LONG_BIT\f[R], but is always at least twice as large as the integer type used to store digits. .SH LIMITS .PP The following are the limits on dc(1): .TP \f[B]DC_LONG_BIT\f[R] The number of bits in the \f[B]long\f[R] type in the environment where dc(1) was built. This determines how many decimal digits can be stored in a single large integer (see the \f[B]PERFORMANCE\f[R] section). .TP \f[B]DC_BASE_DIGS\f[R] The number of decimal digits per large integer (see the \f[B]PERFORMANCE\f[R] section). Depends on \f[B]DC_LONG_BIT\f[R]. .TP \f[B]DC_BASE_POW\f[R] The max decimal number that each large integer can store (see \f[B]DC_BASE_DIGS\f[R]) plus \f[B]1\f[R]. Depends on \f[B]DC_BASE_DIGS\f[R]. .TP \f[B]DC_OVERFLOW_MAX\f[R] The max number that the overflow type (see the \f[B]PERFORMANCE\f[R] section) can hold. Depends on \f[B]DC_LONG_BIT\f[R]. .TP \f[B]DC_BASE_MAX\f[R] The maximum output base. Set at \f[B]DC_BASE_POW\f[R]. .TP \f[B]DC_DIM_MAX\f[R] The maximum size of arrays. Set at \f[B]SIZE_MAX-1\f[R]. .TP \f[B]DC_SCALE_MAX\f[R] The maximum \f[B]scale\f[R]. Set at \f[B]DC_OVERFLOW_MAX-1\f[R]. .TP \f[B]DC_STRING_MAX\f[R] The maximum length of strings. Set at \f[B]DC_OVERFLOW_MAX-1\f[R]. .TP \f[B]DC_NAME_MAX\f[R] The maximum length of identifiers. Set at \f[B]DC_OVERFLOW_MAX-1\f[R]. .TP \f[B]DC_NUM_MAX\f[R] The maximum length of a number (in decimal digits), which includes digits after the decimal point. Set at \f[B]DC_OVERFLOW_MAX-1\f[R]. .TP \f[B]DC_RAND_MAX\f[R] The maximum integer (inclusive) returned by the \f[B]\[cq]\f[R] command, if dc(1). Set at \f[B]2\[ha]DC_LONG_BIT-1\f[R]. .TP Exponent The maximum allowable exponent (positive or negative). Set at \f[B]DC_OVERFLOW_MAX\f[R]. .TP Number of vars The maximum number of vars/arrays. Set at \f[B]SIZE_MAX-1\f[R]. .PP These limits are meant to be effectively non-existent; the limits are so large (at least on 64-bit machines) that there should not be any point at which they become a problem. In fact, memory should be exhausted before these limits should be hit. .SH ENVIRONMENT VARIABLES .PP dc(1) recognizes the following environment variables: .TP \f[B]DC_ENV_ARGS\f[R] This is another way to give command-line arguments to dc(1). They should be in the same format as all other command-line arguments. These are always processed first, so any files given in \f[B]DC_ENV_ARGS\f[R] will be processed before arguments and files given on the command-line. This gives the user the ability to set up \[lq]standard\[rq] options and files to be used at every invocation. The most useful thing for such files to contain would be useful functions that the user might want every time dc(1) runs. Another use would be to use the \f[B]-e\f[R] option to set \f[B]scale\f[R] to a value other than \f[B]0\f[R]. .RS .PP The code that parses \f[B]DC_ENV_ARGS\f[R] will correctly handle quoted arguments, but it does not understand escape sequences. For example, the string \f[B]\[lq]/home/gavin/some dc file.dc\[rq]\f[R] will be correctly parsed, but the string \f[B]\[lq]/home/gavin/some \[dq]dc\[dq] file.dc\[rq]\f[R] will include the backslashes. .PP The quote parsing will handle either kind of quotes, \f[B]\[cq]\f[R] or \f[B]\[lq]\f[R]. Thus, if you have a file with any number of single quotes in the name, you can use double quotes as the outside quotes, as in \f[B]\[lq]some `dc' file.dc\[rq]\f[R], and vice versa if you have a file with double quotes. However, handling a file with both kinds of quotes in \f[B]DC_ENV_ARGS\f[R] is not supported due to the complexity of the parsing, though such files are still supported on the command-line where the parsing is done by the shell. .RE .TP \f[B]DC_LINE_LENGTH\f[R] If this environment variable exists and contains an integer that is greater than \f[B]1\f[R] and is less than \f[B]UINT16_MAX\f[R] (\f[B]2\[ha]16-1\f[R]), dc(1) will output lines to that length, including the backslash newline combo. The default line length is \f[B]70\f[R]. .RS .PP The special value of \f[B]0\f[R] will disable line length checking and print numbers without regard to line length and without backslashes and newlines. .RE .TP \f[B]DC_SIGINT_RESET\f[R] If dc(1) is not in interactive mode (see the \f[B]INTERACTIVE MODE\f[R] section), then this environment variable has no effect because dc(1) exits on \f[B]SIGINT\f[R] when not in interactive mode. .RS .PP However, when dc(1) is in interactive mode, then if this environment variable exists and contains an integer, a non-zero value makes dc(1) reset on \f[B]SIGINT\f[R], rather than exit, and zero makes dc(1) exit. If this environment variable exists and is \f[I]not\f[R] an integer, then dc(1) will exit on \f[B]SIGINT\f[R]. .PP This environment variable overrides the default, which can be queried with the \f[B]-h\f[R] or \f[B]--help\f[R] options. .RE .TP \f[B]DC_TTY_MODE\f[R] If TTY mode is \f[I]not\f[R] available (see the \f[B]TTY MODE\f[R] section), then this environment variable has no effect. .RS .PP However, when TTY mode is available, then if this environment variable exists and contains an integer, then a non-zero value makes dc(1) use TTY mode, and zero makes dc(1) not use TTY mode. .PP This environment variable overrides the default, which can be queried with the \f[B]-h\f[R] or \f[B]--help\f[R] options. .RE .TP \f[B]DC_PROMPT\f[R] If TTY mode is \f[I]not\f[R] available (see the \f[B]TTY MODE\f[R] section), then this environment variable has no effect. .RS .PP However, when TTY mode is available, then if this environment variable exists and contains an integer, a non-zero value makes dc(1) use a prompt, and zero or a non-integer makes dc(1) not use a prompt. If this environment variable does not exist and \f[B]DC_TTY_MODE\f[R] does, then the value of the \f[B]DC_TTY_MODE\f[R] environment variable is used. .PP This environment variable and the \f[B]DC_TTY_MODE\f[R] environment variable override the default, which can be queried with the \f[B]-h\f[R] or \f[B]--help\f[R] options. .RE +.TP +\f[B]DC_EXPR_EXIT\f[R] +If any expressions or expression files are given on the command-line +with \f[B]-e\f[R], \f[B]--expression\f[R], \f[B]-f\f[R], or +\f[B]--file\f[R], then if this environment variable exists and contains +an integer, a non-zero value makes dc(1) exit after executing the +expressions and expression files, and a non-zero value makes dc(1) not +exit. +.RS +.PP +This environment variable overrides the default, which can be queried +with the \f[B]-h\f[R] or \f[B]--help\f[R] options. +.RE .SH EXIT STATUS .PP dc(1) returns the following exit statuses: .TP \f[B]0\f[R] No error. .TP \f[B]1\f[R] A math error occurred. This follows standard practice of using \f[B]1\f[R] for expected errors, since math errors will happen in the process of normal execution. .RS .PP Math errors include divide by \f[B]0\f[R], taking the square root of a negative number, using a negative number as a bound for the pseudo-random number generator, attempting to convert a negative number to a hardware integer, overflow when converting a number to a hardware integer, overflow when calculating the size of a number, and attempting to use a non-integer where an integer is required. .PP Converting to a hardware integer happens for the second operand of the power (\f[B]\[ha]\f[R]), places (\f[B]\[at]\f[R]), left shift (\f[B]H\f[R]), and right shift (\f[B]h\f[R]) operators. .RE .TP \f[B]2\f[R] A parse error occurred. .RS .PP Parse errors include unexpected \f[B]EOF\f[R], using an invalid character, failing to find the end of a string or comment, and using a token where it is invalid. .RE .TP \f[B]3\f[R] A runtime error occurred. .RS .PP Runtime errors include assigning an invalid number to any global (\f[B]ibase\f[R], \f[B]obase\f[R], or \f[B]scale\f[R]), giving a bad expression to a \f[B]read()\f[R] call, calling \f[B]read()\f[R] inside of a \f[B]read()\f[R] call, type errors (including attempting to execute a number), and attempting an operation when the stack has too few elements. .RE .TP \f[B]4\f[R] A fatal error occurred. .RS .PP Fatal errors include memory allocation errors, I/O errors, failing to open files, attempting to use files that do not have only ASCII characters (dc(1) only accepts ASCII characters), attempting to open a directory as a file, and giving invalid command-line options. .RE .PP The exit status \f[B]4\f[R] is special; when a fatal error occurs, dc(1) always exits and returns \f[B]4\f[R], no matter what mode dc(1) is in. .PP The other statuses will only be returned when dc(1) is not in interactive mode (see the \f[B]INTERACTIVE MODE\f[R] section), since dc(1) resets its state (see the \f[B]RESET\f[R] section) and accepts more input when one of those errors occurs in interactive mode. This is also the case when interactive mode is forced by the \f[B]-i\f[R] flag or \f[B]--interactive\f[R] option. .PP These exit statuses allow dc(1) to be used in shell scripting with error checking, and its normal behavior can be forced by using the \f[B]-i\f[R] flag or \f[B]--interactive\f[R] option. .SH INTERACTIVE MODE .PP Like bc(1), dc(1) has an interactive mode and a non-interactive mode. Interactive mode is turned on automatically when both \f[B]stdin\f[R] and \f[B]stdout\f[R] are hooked to a terminal, but the \f[B]-i\f[R] flag and \f[B]--interactive\f[R] option can turn it on in other situations. .PP In interactive mode, dc(1) attempts to recover from errors (see the \f[B]RESET\f[R] section), and in normal execution, flushes \f[B]stdout\f[R] as soon as execution is done for the current input. dc(1) may also reset on \f[B]SIGINT\f[R] instead of exit, depending on the contents of, or default for, the \f[B]DC_SIGINT_RESET\f[R] environment variable (see the \f[B]ENVIRONMENT VARIABLES\f[R] section). .SH TTY MODE .PP If \f[B]stdin\f[R], \f[B]stdout\f[R], and \f[B]stderr\f[R] are all connected to a TTY, then \[lq]TTY mode\[rq] is considered to be available, and thus, dc(1) can turn on TTY mode, subject to some settings. .PP If there is the environment variable \f[B]DC_TTY_MODE\f[R] in the environment (see the \f[B]ENVIRONMENT VARIABLES\f[R] section), then if that environment variable contains a non-zero integer, dc(1) will turn on TTY mode when \f[B]stdin\f[R], \f[B]stdout\f[R], and \f[B]stderr\f[R] are all connected to a TTY. If the \f[B]DC_TTY_MODE\f[R] environment variable exists but is \f[I]not\f[R] a non-zero integer, then dc(1) will not turn TTY mode on. .PP If the environment variable \f[B]DC_TTY_MODE\f[R] does \f[I]not\f[R] exist, the default setting is used. The default setting can be queried with the \f[B]-h\f[R] or \f[B]--help\f[R] options. .PP TTY mode is different from interactive mode because interactive mode is required in the bc(1) specification (https://pubs.opengroup.org/onlinepubs/9699919799/utilities/bc.html), and interactive mode requires only \f[B]stdin\f[R] and \f[B]stdout\f[R] to be connected to a terminal. .SS Prompt .PP If TTY mode is available, then a prompt can be enabled. Like TTY mode itself, it can be turned on or off with an environment variable: \f[B]DC_PROMPT\f[R] (see the \f[B]ENVIRONMENT VARIABLES\f[R] section). .PP If the environment variable \f[B]DC_PROMPT\f[R] exists and is a non-zero integer, then the prompt is turned on when \f[B]stdin\f[R], \f[B]stdout\f[R], and \f[B]stderr\f[R] are connected to a TTY and the \f[B]-P\f[R] and \f[B]--no-prompt\f[R] options were not used. The read prompt will be turned on under the same conditions, except that the \f[B]-R\f[R] and \f[B]--no-read-prompt\f[R] options must also not be used. .PP However, if \f[B]DC_PROMPT\f[R] does not exist, the prompt can be enabled or disabled with the \f[B]DC_TTY_MODE\f[R] environment variable, the \f[B]-P\f[R] and \f[B]--no-prompt\f[R] options, and the \f[B]-R\f[R] and \f[B]--no-read-prompt\f[R] options. See the \f[B]ENVIRONMENT VARIABLES\f[R] and \f[B]OPTIONS\f[R] sections for more details. .SH SIGNAL HANDLING .PP Sending a \f[B]SIGINT\f[R] will cause dc(1) to do one of two things. .PP If dc(1) is not in interactive mode (see the \f[B]INTERACTIVE MODE\f[R] section), or the \f[B]DC_SIGINT_RESET\f[R] environment variable (see the \f[B]ENVIRONMENT VARIABLES\f[R] section), or its default, is either not an integer or it is zero, dc(1) will exit. .PP However, if dc(1) is in interactive mode, and the \f[B]DC_SIGINT_RESET\f[R] or its default is an integer and non-zero, then dc(1) will stop executing the current input and reset (see the \f[B]RESET\f[R] section) upon receiving a \f[B]SIGINT\f[R]. .PP Note that \[lq]current input\[rq] can mean one of two things. If dc(1) is processing input from \f[B]stdin\f[R] in interactive mode, it will ask for more input. If dc(1) is processing input from a file in interactive mode, it will stop processing the file and start processing the next file, if one exists, or ask for input from \f[B]stdin\f[R] if no other file exists. .PP This means that if a \f[B]SIGINT\f[R] is sent to dc(1) as it is executing a file, it can seem as though dc(1) did not respond to the signal since it will immediately start executing the next file. This is by design; most files that users execute when interacting with dc(1) have function definitions, which are quick to parse. If a file takes a long time to execute, there may be a bug in that file. The rest of the files could still be executed without problem, allowing the user to continue. .PP \f[B]SIGTERM\f[R] and \f[B]SIGQUIT\f[R] cause dc(1) to clean up and exit, and it uses the default handler for all other signals. .SH LOCALES .PP This dc(1) ships with support for adding error messages for different locales and thus, supports \f[B]LC_MESSAGES\f[R]. .SH SEE ALSO .PP bc(1) .SH STANDARDS .PP The dc(1) utility operators are compliant with the operators in the bc(1) IEEE Std 1003.1-2017 (\[lq]POSIX.1-2017\[rq]) (https://pubs.opengroup.org/onlinepubs/9699919799/utilities/bc.html) specification. .SH BUGS .PP None are known. Report bugs at https://git.yzena.com/gavin/bc. .SH AUTHOR .PP Gavin D. Howard and contributors. diff --git a/contrib/bc/manuals/dc/H.1.md b/contrib/bc/manuals/dc/H.1.md index 647d486adc38..c97cc8b58eef 100644 --- a/contrib/bc/manuals/dc/H.1.md +++ b/contrib/bc/manuals/dc/H.1.md @@ -1,1361 +1,1372 @@ # Name dc - arbitrary-precision decimal reverse-Polish notation calculator # SYNOPSIS **dc** [**-hiPRvVx**] [**-\-version**] [**-\-help**] [**-\-interactive**] [**-\-no-prompt**] [**-\-no-read-prompt**] [**-\-extended-register**] [**-e** *expr*] [**-\-expression**=*expr*...] [**-f** *file*...] [**-\-file**=*file*...] [*file*...] # DESCRIPTION dc(1) is an arbitrary-precision calculator. It uses a stack (reverse Polish notation) to store numbers and results of computations. Arithmetic operations pop arguments off of the stack and push the results. If no files are given on the command-line, then dc(1) reads from **stdin** (see the **STDIN** section). Otherwise, those files are processed, and dc(1) will then exit. If a user wants to set up a standard environment, they can use **DC_ENV_ARGS** (see the **ENVIRONMENT VARIABLES** section). For example, if a user wants the **scale** always set to **10**, they can set **DC_ENV_ARGS** to **-e 10k**, and this dc(1) will always start with a **scale** of **10**. # OPTIONS The following are the options that dc(1) accepts. **-h**, **-\-help** : Prints a usage message and quits. **-v**, **-V**, **-\-version** : Print the version information (copyright header) and exit. **-i**, **-\-interactive** : Forces interactive mode. (See the **INTERACTIVE MODE** section.) This is a **non-portable extension**. **-L**, **-\-no-line-length** : Disables line length checking and prints numbers without backslashes and newlines. In other words, this option sets **BC_LINE_LENGTH** to **0** (see the **ENVIRONMENT VARIABLES** section). This is a **non-portable extension**. **-P**, **-\-no-prompt** : Disables the prompt in TTY mode. (The prompt is only enabled in TTY mode. See the **TTY MODE** section.) This is mostly for those users that do not want a prompt or are not used to having them in dc(1). Most of those users would want to put this option in **DC_ENV_ARGS**. These options override the **DC_PROMPT** and **DC_TTY_MODE** environment variables (see the **ENVIRONMENT VARIABLES** section). This is a **non-portable extension**. **-R**, **-\-no-read-prompt** : Disables the read prompt in TTY mode. (The read prompt is only enabled in TTY mode. See the **TTY MODE** section.) This is mostly for those users that do not want a read prompt or are not used to having them in dc(1). Most of those users would want to put this option in **BC_ENV_ARGS** (see the **ENVIRONMENT VARIABLES** section). This option is also useful in hash bang lines of dc(1) scripts that prompt for user input. This option does not disable the regular prompt because the read prompt is only used when the **?** command is used. These options *do* override the **DC_PROMPT** and **DC_TTY_MODE** environment variables (see the **ENVIRONMENT VARIABLES** section), but only for the read prompt. This is a **non-portable extension**. **-x** **-\-extended-register** : Enables extended register mode. See the *Extended Register Mode* subsection of the **REGISTERS** section for more information. This is a **non-portable extension**. **-z**, **-\-leading-zeroes** : Makes bc(1) print all numbers greater than **-1** and less than **1**, and not equal to **0**, with a leading zero. This can be set for individual numbers with the **plz(x)**, plznl(x)**, **pnlz(x)**, and **pnlznl(x)** functions in the extended math library (see the **LIBRARY** section). This is a **non-portable extension**. **-e** *expr*, **-\-expression**=*expr* : Evaluates *expr*. If multiple expressions are given, they are evaluated in order. If files are given as well (see below), the expressions and files are evaluated in the order given. This means that if a file is given before an expression, the file is read in and evaluated first. If this option is given on the command-line (i.e., not in **DC_ENV_ARGS**, see the **ENVIRONMENT VARIABLES** section), then after processing all expressions and files, dc(1) will exit, unless **-** (**stdin**) was given as an argument at least once to **-f** or **-\-file**, whether on the command-line or in **DC_ENV_ARGS**. However, if any other **-e**, **-\-expression**, **-f**, or **-\-file** arguments are given after **-f-** or equivalent is given, dc(1) will give a fatal error and exit. This is a **non-portable extension**. **-f** *file*, **-\-file**=*file* : Reads in *file* and evaluates it, line by line, as though it were read through **stdin**. If expressions are also given (see above), the expressions are evaluated in the order given. If this option is given on the command-line (i.e., not in **DC_ENV_ARGS**, see the **ENVIRONMENT VARIABLES** section), then after processing all expressions and files, dc(1) will exit, unless **-** (**stdin**) was given as an argument at least once to **-f** or **-\-file**. However, if any other **-e**, **-\-expression**, **-f**, or **-\-file** arguments are given after **-f-** or equivalent is given, dc(1) will give a fatal error and exit. This is a **non-portable extension**. All long options are **non-portable extensions**. # STDIN If no files are given on the command-line and no files or expressions are given by the **-f**, **-\-file**, **-e**, or **-\-expression** options, then dc(1) read from **stdin**. However, there is a caveat to this. First, **stdin** is evaluated a line at a time. The only exception to this is if a string has been finished, but not ended. This means that, except for escaped brackets, all brackets must be balanced before dc(1) parses and executes. # STDOUT Any non-error output is written to **stdout**. In addition, if history (see the **HISTORY** section) and the prompt (see the **TTY MODE** section) are enabled, both are output to **stdout**. **Note**: Unlike other dc(1) implementations, this dc(1) will issue a fatal error (see the **EXIT STATUS** section) if it cannot write to **stdout**, so if **stdout** is closed, as in **dc >&-**, it will quit with an error. This is done so that dc(1) can report problems when **stdout** is redirected to a file. If there are scripts that depend on the behavior of other dc(1) implementations, it is recommended that those scripts be changed to redirect **stdout** to **/dev/null**. # STDERR Any error output is written to **stderr**. **Note**: Unlike other dc(1) implementations, this dc(1) will issue a fatal error (see the **EXIT STATUS** section) if it cannot write to **stderr**, so if **stderr** is closed, as in **dc 2>&-**, it will quit with an error. This is done so that dc(1) can exit with an error code when **stderr** is redirected to a file. If there are scripts that depend on the behavior of other dc(1) implementations, it is recommended that those scripts be changed to redirect **stderr** to **/dev/null**. # SYNTAX Each item in the input source code, either a number (see the **NUMBERS** section) or a command (see the **COMMANDS** section), is processed and executed, in order. Input is processed immediately when entered. **ibase** is a register (see the **REGISTERS** section) that determines how to interpret constant numbers. It is the "input" base, or the number base used for interpreting input numbers. **ibase** is initially **10**. The max allowable value for **ibase** is **16**. The min allowable value for **ibase** is **2**. The max allowable value for **ibase** can be queried in dc(1) programs with the **T** command. **obase** is a register (see the **REGISTERS** section) that determines how to output results. It is the "output" base, or the number base used for outputting numbers. **obase** is initially **10**. The max allowable value for **obase** is **DC_BASE_MAX** and can be queried with the **U** command. The min allowable value for **obase** is **0**. If **obase** is **0**, values are output in scientific notation, and if **obase** is **1**, values are output in engineering notation. Otherwise, values are output in the specified base. Outputting in scientific and engineering notations are **non-portable extensions**. The *scale* of an expression is the number of digits in the result of the expression right of the decimal point, and **scale** is a register (see the **REGISTERS** section) that sets the precision of any operations (with exceptions). **scale** is initially **0**. **scale** cannot be negative. The max allowable value for **scale** can be queried in dc(1) programs with the **V** command. **seed** is a register containing the current seed for the pseudo-random number generator. If the current value of **seed** is queried and stored, then if it is assigned to **seed** later, the pseudo-random number generator is guaranteed to produce the same sequence of pseudo-random numbers that were generated after the value of **seed** was first queried. Multiple values assigned to **seed** can produce the same sequence of pseudo-random numbers. Likewise, when a value is assigned to **seed**, it is not guaranteed that querying **seed** immediately after will return the same value. In addition, the value of **seed** will change after any call to the **'** command or the **"** command that does not get receive a value of **0** or **1**. The maximum integer returned by the **'** command can be queried with the **W** command. **Note**: The values returned by the pseudo-random number generator with the **'** and **"** commands are guaranteed to **NOT** be cryptographically secure. This is a consequence of using a seeded pseudo-random number generator. However, they *are* guaranteed to be reproducible with identical **seed** values. This means that the pseudo-random values from dc(1) should only be used where a reproducible stream of pseudo-random numbers is *ESSENTIAL*. In any other case, use a non-seeded pseudo-random number generator. The pseudo-random number generator, **seed**, and all associated operations are **non-portable extensions**. ## Comments Comments go from **#** until, and not including, the next newline. This is a **non-portable extension**. # NUMBERS Numbers are strings made up of digits, uppercase letters up to **F**, and at most **1** period for a radix. Numbers can have up to **DC_NUM_MAX** digits. Uppercase letters are equal to **9** + their position in the alphabet (i.e., **A** equals **10**, or **9+1**). If a digit or letter makes no sense with the current value of **ibase**, they are set to the value of the highest valid digit in **ibase**. Single-character numbers (i.e., **A** alone) take the value that they would have if they were valid digits, regardless of the value of **ibase**. This means that **A** alone always equals decimal **10** and **F** alone always equals decimal **15**. In addition, dc(1) accepts numbers in scientific notation. These have the form **\e\**. The exponent (the portion after the **e**) must be an integer. An example is **1.89237e9**, which is equal to **1892370000**. Negative exponents are also allowed, so **4.2890e_3** is equal to **0.0042890**. **WARNING**: Both the number and the exponent in scientific notation are interpreted according to the current **ibase**, but the number is still multiplied by **10\^exponent** regardless of the current **ibase**. For example, if **ibase** is **16** and dc(1) is given the number string **FFeA**, the resulting decimal number will be **2550000000000**, and if dc(1) is given the number string **10e_4**, the resulting decimal number will be **0.0016**. Accepting input as scientific notation is a **non-portable extension**. # COMMANDS The valid commands are listed below. ## Printing These commands are used for printing. Note that both scientific notation and engineering notation are available for printing numbers. Scientific notation is activated by assigning **0** to **obase** using **0o**, and engineering notation is activated by assigning **1** to **obase** using **1o**. To deactivate them, just assign a different value to **obase**. Printing numbers in scientific notation and/or engineering notation is a **non-portable extension**. **p** : Prints the value on top of the stack, whether number or string, and prints a newline after. This does not alter the stack. **n** : Prints the value on top of the stack, whether number or string, and pops it off of the stack. **P** : Pops a value off the stack. If the value is a number, it is truncated and the absolute value of the result is printed as though **obase** is **256** and each digit is interpreted as an 8-bit ASCII character, making it a byte stream. If the value is a string, it is printed without a trailing newline. This is a **non-portable extension**. **f** : Prints the entire contents of the stack, in order from newest to oldest, without altering anything. Users should use this command when they get lost. ## Arithmetic These are the commands used for arithmetic. **+** : The top two values are popped off the stack, added, and the result is pushed onto the stack. The *scale* of the result is equal to the max *scale* of both operands. **-** : The top two values are popped off the stack, subtracted, and the result is pushed onto the stack. The *scale* of the result is equal to the max *scale* of both operands. **\*** : The top two values are popped off the stack, multiplied, and the result is pushed onto the stack. If **a** is the *scale* of the first expression and **b** is the *scale* of the second expression, the *scale* of the result is equal to **min(a+b,max(scale,a,b))** where **min()** and **max()** return the obvious values. **/** : The top two values are popped off the stack, divided, and the result is pushed onto the stack. The *scale* of the result is equal to **scale**. The first value popped off of the stack must be non-zero. **%** : The top two values are popped off the stack, remaindered, and the result is pushed onto the stack. Remaindering is equivalent to 1) Computing **a/b** to current **scale**, and 2) Using the result of step 1 to calculate **a-(a/b)\*b** to *scale* **max(scale+scale(b),scale(a))**. The first value popped off of the stack must be non-zero. **~** : The top two values are popped off the stack, divided and remaindered, and the results (divided first, remainder second) are pushed onto the stack. This is equivalent to **x y / x y %** except that **x** and **y** are only evaluated once. The first value popped off of the stack must be non-zero. This is a **non-portable extension**. **\^** : The top two values are popped off the stack, the second is raised to the power of the first, and the result is pushed onto the stack. The *scale* of the result is equal to **scale**. The first value popped off of the stack must be an integer, and if that value is negative, the second value popped off of the stack must be non-zero. **v** : The top value is popped off the stack, its square root is computed, and the result is pushed onto the stack. The *scale* of the result is equal to **scale**. The value popped off of the stack must be non-negative. **\_** : If this command *immediately* precedes a number (i.e., no spaces or other commands), then that number is input as a negative number. Otherwise, the top value on the stack is popped and copied, and the copy is negated and pushed onto the stack. This behavior without a number is a **non-portable extension**. **b** : The top value is popped off the stack, and if it is zero, it is pushed back onto the stack. Otherwise, its absolute value is pushed onto the stack. This is a **non-portable extension**. **|** : The top three values are popped off the stack, a modular exponentiation is computed, and the result is pushed onto the stack. The first value popped is used as the reduction modulus and must be an integer and non-zero. The second value popped is used as the exponent and must be an integer and non-negative. The third value popped is the base and must be an integer. This is a **non-portable extension**. **\$** : The top value is popped off the stack and copied, and the copy is truncated and pushed onto the stack. This is a **non-portable extension**. **\@** : The top two values are popped off the stack, and the precision of the second is set to the value of the first, whether by truncation or extension. The first value popped off of the stack must be an integer and non-negative. This is a **non-portable extension**. **H** : The top two values are popped off the stack, and the second is shifted left (radix shifted right) to the value of the first. The first value popped off of the stack must be an integer and non-negative. This is a **non-portable extension**. **h** : The top two values are popped off the stack, and the second is shifted right (radix shifted left) to the value of the first. The first value popped off of the stack must be an integer and non-negative. This is a **non-portable extension**. **G** : The top two values are popped off of the stack, they are compared, and a **1** is pushed if they are equal, or **0** otherwise. This is a **non-portable extension**. **N** : The top value is popped off of the stack, and if it a **0**, a **1** is pushed; otherwise, a **0** is pushed. This is a **non-portable extension**. **(** : The top two values are popped off of the stack, they are compared, and a **1** is pushed if the first is less than the second, or **0** otherwise. This is a **non-portable extension**. **{** : The top two values are popped off of the stack, they are compared, and a **1** is pushed if the first is less than or equal to the second, or **0** otherwise. This is a **non-portable extension**. **)** : The top two values are popped off of the stack, they are compared, and a **1** is pushed if the first is greater than the second, or **0** otherwise. This is a **non-portable extension**. **}** : The top two values are popped off of the stack, they are compared, and a **1** is pushed if the first is greater than or equal to the second, or **0** otherwise. This is a **non-portable extension**. **M** : The top two values are popped off of the stack. If they are both non-zero, a **1** is pushed onto the stack. If either of them is zero, or both of them are, then a **0** is pushed onto the stack. This is like the **&&** operator in bc(1), and it is *not* a short-circuit operator. This is a **non-portable extension**. **m** : The top two values are popped off of the stack. If at least one of them is non-zero, a **1** is pushed onto the stack. If both of them are zero, then a **0** is pushed onto the stack. This is like the **||** operator in bc(1), and it is *not* a short-circuit operator. This is a **non-portable extension**. ## Pseudo-Random Number Generator dc(1) has a built-in pseudo-random number generator. These commands query the pseudo-random number generator. (See Parameters for more information about the **seed** value that controls the pseudo-random number generator.) The pseudo-random number generator is guaranteed to **NOT** be cryptographically secure. **'** : Generates an integer between 0 and **DC_RAND_MAX**, inclusive (see the **LIMITS** section). The generated integer is made as unbiased as possible, subject to the limitations of the pseudo-random number generator. This is a **non-portable extension**. **"** : Pops a value off of the stack, which is used as an **exclusive** upper bound on the integer that will be generated. If the bound is negative or is a non-integer, an error is raised, and dc(1) resets (see the **RESET** section) while **seed** remains unchanged. If the bound is larger than **DC_RAND_MAX**, the higher bound is honored by generating several pseudo-random integers, multiplying them by appropriate powers of **DC_RAND_MAX+1**, and adding them together. Thus, the size of integer that can be generated with this command is unbounded. Using this command will change the value of **seed**, unless the operand is **0** or **1**. In that case, **0** is pushed onto the stack, and **seed** is *not* changed. The generated integer is made as unbiased as possible, subject to the limitations of the pseudo-random number generator. This is a **non-portable extension**. ## Stack Control These commands control the stack. **c** : Removes all items from ("clears") the stack. **d** : Copies the item on top of the stack ("duplicates") and pushes the copy onto the stack. **r** : Swaps ("reverses") the two top items on the stack. **R** : Pops ("removes") the top value from the stack. ## Register Control These commands control registers (see the **REGISTERS** section). **s**_r_ : Pops the value off the top of the stack and stores it into register *r*. **l**_r_ : Copies the value in register *r* and pushes it onto the stack. This does not alter the contents of *r*. **S**_r_ : Pops the value off the top of the (main) stack and pushes it onto the stack of register *r*. The previous value of the register becomes inaccessible. **L**_r_ : Pops the value off the top of the stack for register *r* and push it onto the main stack. The previous value in the stack for register *r*, if any, is now accessible via the **l**_r_ command. ## Parameters These commands control the values of **ibase**, **obase**, **scale**, and **seed**. Also see the **SYNTAX** section. **i** : Pops the value off of the top of the stack and uses it to set **ibase**, which must be between **2** and **16**, inclusive. If the value on top of the stack has any *scale*, the *scale* is ignored. **o** : Pops the value off of the top of the stack and uses it to set **obase**, which must be between **0** and **DC_BASE_MAX**, inclusive (see the **LIMITS** section and the **NUMBERS** section). If the value on top of the stack has any *scale*, the *scale* is ignored. **k** : Pops the value off of the top of the stack and uses it to set **scale**, which must be non-negative. If the value on top of the stack has any *scale*, the *scale* is ignored. **j** : Pops the value off of the top of the stack and uses it to set **seed**. The meaning of **seed** is dependent on the current pseudo-random number generator but is guaranteed to not change except for new major versions. The *scale* and sign of the value may be significant. If a previously used **seed** value is used again, the pseudo-random number generator is guaranteed to produce the same sequence of pseudo-random numbers as it did when the **seed** value was previously used. The exact value assigned to **seed** is not guaranteed to be returned if the **J** command is used. However, if **seed** *does* return a different value, both values, when assigned to **seed**, are guaranteed to produce the same sequence of pseudo-random numbers. This means that certain values assigned to **seed** will not produce unique sequences of pseudo-random numbers. There is no limit to the length (number of significant decimal digits) or *scale* of the value that can be assigned to **seed**. This is a **non-portable extension**. **I** : Pushes the current value of **ibase** onto the main stack. **O** : Pushes the current value of **obase** onto the main stack. **K** : Pushes the current value of **scale** onto the main stack. **J** : Pushes the current value of **seed** onto the main stack. This is a **non-portable extension**. **T** : Pushes the maximum allowable value of **ibase** onto the main stack. This is a **non-portable extension**. **U** : Pushes the maximum allowable value of **obase** onto the main stack. This is a **non-portable extension**. **V** : Pushes the maximum allowable value of **scale** onto the main stack. This is a **non-portable extension**. **W** : Pushes the maximum (inclusive) integer that can be generated with the **'** pseudo-random number generator command. This is a **non-portable extension**. ## Strings The following commands control strings. dc(1) can work with both numbers and strings, and registers (see the **REGISTERS** section) can hold both strings and numbers. dc(1) always knows whether the contents of a register are a string or a number. While arithmetic operations have to have numbers, and will print an error if given a string, other commands accept strings. Strings can also be executed as macros. For example, if the string **[1pR]** is executed as a macro, then the code **1pR** is executed, meaning that the **1** will be printed with a newline after and then popped from the stack. **\[**_characters_**\]** : Makes a string containing *characters* and pushes it onto the stack. If there are brackets (**\[** and **\]**) in the string, then they must be balanced. Unbalanced brackets can be escaped using a backslash (**\\**) character. If there is a backslash character in the string, the character after it (even another backslash) is put into the string verbatim, but the (first) backslash is not. **a** : The value on top of the stack is popped. If it is a number, it is truncated and its absolute value is taken. The result mod **256** is calculated. If that result is **0**, push an empty string; otherwise, push a one-character string where the character is the result of the mod interpreted as an ASCII character. If it is a string, then a new string is made. If the original string is empty, the new string is empty. If it is not, then the first character of the original string is used to create the new string as a one-character string. The new string is then pushed onto the stack. This is a **non-portable extension**. **x** : Pops a value off of the top of the stack. If it is a number, it is pushed back onto the stack. If it is a string, it is executed as a macro. This behavior is the norm whenever a macro is executed, whether by this command or by the conditional execution commands below. **\>**_r_ : Pops two values off of the stack that must be numbers and compares them. If the first value is greater than the second, then the contents of register *r* are executed. For example, **0 1>a** will execute the contents of register **a**, and **1 0>a** will not. If either or both of the values are not numbers, dc(1) will raise an error and reset (see the **RESET** section). **>**_r_**e**_s_ : Like the above, but will execute register *s* if the comparison fails. If either or both of the values are not numbers, dc(1) will raise an error and reset (see the **RESET** section). This is a **non-portable extension**. **!\>**_r_ : Pops two values off of the stack that must be numbers and compares them. If the first value is not greater than the second (less than or equal to), then the contents of register *r* are executed. If either or both of the values are not numbers, dc(1) will raise an error and reset (see the **RESET** section). **!\>**_r_**e**_s_ : Like the above, but will execute register *s* if the comparison fails. If either or both of the values are not numbers, dc(1) will raise an error and reset (see the **RESET** section). This is a **non-portable extension**. **\<**_r_ : Pops two values off of the stack that must be numbers and compares them. If the first value is less than the second, then the contents of register *r* are executed. If either or both of the values are not numbers, dc(1) will raise an error and reset (see the **RESET** section). **\<**_r_**e**_s_ : Like the above, but will execute register *s* if the comparison fails. If either or both of the values are not numbers, dc(1) will raise an error and reset (see the **RESET** section). This is a **non-portable extension**. **!\<**_r_ : Pops two values off of the stack that must be numbers and compares them. If the first value is not less than the second (greater than or equal to), then the contents of register *r* are executed. If either or both of the values are not numbers, dc(1) will raise an error and reset (see the **RESET** section). **!\<**_r_**e**_s_ : Like the above, but will execute register *s* if the comparison fails. If either or both of the values are not numbers, dc(1) will raise an error and reset (see the **RESET** section). This is a **non-portable extension**. **=**_r_ : Pops two values off of the stack that must be numbers and compares them. If the first value is equal to the second, then the contents of register *r* are executed. If either or both of the values are not numbers, dc(1) will raise an error and reset (see the **RESET** section). **=**_r_**e**_s_ : Like the above, but will execute register *s* if the comparison fails. If either or both of the values are not numbers, dc(1) will raise an error and reset (see the **RESET** section). This is a **non-portable extension**. **!=**_r_ : Pops two values off of the stack that must be numbers and compares them. If the first value is not equal to the second, then the contents of register *r* are executed. If either or both of the values are not numbers, dc(1) will raise an error and reset (see the **RESET** section). **!=**_r_**e**_s_ : Like the above, but will execute register *s* if the comparison fails. If either or both of the values are not numbers, dc(1) will raise an error and reset (see the **RESET** section). This is a **non-portable extension**. **?** : Reads a line from the **stdin** and executes it. This is to allow macros to request input from users. **q** : During execution of a macro, this exits the execution of that macro and the execution of the macro that executed it. If there are no macros, or only one macro executing, dc(1) exits. **Q** : Pops a value from the stack which must be non-negative and is used the number of macro executions to pop off of the execution stack. If the number of levels to pop is greater than the number of executing macros, dc(1) exits. **,** : Pushes the depth of the execution stack onto the stack. The execution stack is the stack of string executions. The number that is pushed onto the stack is exactly as many as is needed to make dc(1) exit with the **Q** command, so the sequence **,Q** will make dc(1) exit. ## Status These commands query status of the stack or its top value. **Z** : Pops a value off of the stack. If it is a number, calculates the number of significant decimal digits it has and pushes the result. It will push **1** if the argument is **0** with no decimal places. If it is a string, pushes the number of characters the string has. **X** : Pops a value off of the stack. If it is a number, pushes the *scale* of the value onto the stack. If it is a string, pushes **0**. **z** : Pushes the current depth of the stack (before execution of this command) onto the stack. **y**_r_ : Pushes the current stack depth of the register *r* onto the main stack. Because each register has a depth of **1** (with the value **0** in the top item) when dc(1) starts, dc(1) requires that each register's stack must always have at least one item; dc(1) will give an error and reset otherwise (see the **RESET** section). This means that this command will never push **0**. This is a **non-portable extension**. ## Arrays These commands manipulate arrays. **:**_r_ : Pops the top two values off of the stack. The second value will be stored in the array *r* (see the **REGISTERS** section), indexed by the first value. **;**_r_ : Pops the value on top of the stack and uses it as an index into the array *r*. The selected value is then pushed onto the stack. **Y**_r_ : Pushes the length of the array *r* onto the stack. This is a **non-portable extension**. ## Global Settings These commands retrieve global settings. These are the only commands that require multiple specific characters, and all of them begin with the letter **g**. Only the characters below are allowed after the character **g**; any other character produces a parse error (see the **ERRORS** section). **gl** : Pushes the line length set by **DC_LINE_LENGTH** (see the **ENVIRONMENT VARIABLES** section) onto the stack. **gz** : Pushes **0** onto the stack if the leading zero setting has not been enabled with the **-z** or **-\-leading-zeroes** options (see the **OPTIONS** section), non-zero otherwise. # REGISTERS Registers are names that can store strings, numbers, and arrays. (Number/string registers do not interfere with array registers.) Each register is also its own stack, so the current register value is the top of the stack for the register. All registers, when first referenced, have one value (**0**) in their stack, and it is a runtime error to attempt to pop that item off of the register stack. In non-extended register mode, a register name is just the single character that follows any command that needs a register name. The only exceptions are: a newline (**'\\n'**) and a left bracket (**'['**); it is a parse error for a newline or a left bracket to be used as a register name. ## Extended Register Mode Unlike most other dc(1) implentations, this dc(1) provides nearly unlimited amounts of registers, if extended register mode is enabled. If extended register mode is enabled (**-x** or **-\-extended-register** command-line arguments are given), then normal single character registers are used *unless* the character immediately following a command that needs a register name is a space (according to **isspace()**) and not a newline (**'\\n'**). In that case, the register name is found according to the regex **\[a-z\]\[a-z0-9\_\]\*** (like bc(1) identifiers), and it is a parse error if the next non-space characters do not match that regex. # RESET When dc(1) encounters an error or a signal that it has a non-default handler for, it resets. This means that several things happen. First, any macros that are executing are stopped and popped off the stack. The behavior is not unlike that of exceptions in programming languages. Then the execution point is set so that any code waiting to execute (after all macros returned) is skipped. Thus, when dc(1) resets, it skips any remaining code waiting to be executed. Then, if it is interactive mode, and the error was not a fatal error (see the **EXIT STATUS** section), it asks for more input; otherwise, it exits with the appropriate return code. # PERFORMANCE Most dc(1) implementations use **char** types to calculate the value of **1** decimal digit at a time, but that can be slow. This dc(1) does something different. It uses large integers to calculate more than **1** decimal digit at a time. If built in a environment where **DC_LONG_BIT** (see the **LIMITS** section) is **64**, then each integer has **9** decimal digits. If built in an environment where **DC_LONG_BIT** is **32** then each integer has **4** decimal digits. This value (the number of decimal digits per large integer) is called **DC_BASE_DIGS**. In addition, this dc(1) uses an even larger integer for overflow checking. This integer type depends on the value of **DC_LONG_BIT**, but is always at least twice as large as the integer type used to store digits. # LIMITS The following are the limits on dc(1): **DC_LONG_BIT** : The number of bits in the **long** type in the environment where dc(1) was built. This determines how many decimal digits can be stored in a single large integer (see the **PERFORMANCE** section). **DC_BASE_DIGS** : The number of decimal digits per large integer (see the **PERFORMANCE** section). Depends on **DC_LONG_BIT**. **DC_BASE_POW** : The max decimal number that each large integer can store (see **DC_BASE_DIGS**) plus **1**. Depends on **DC_BASE_DIGS**. **DC_OVERFLOW_MAX** : The max number that the overflow type (see the **PERFORMANCE** section) can hold. Depends on **DC_LONG_BIT**. **DC_BASE_MAX** : The maximum output base. Set at **DC_BASE_POW**. **DC_DIM_MAX** : The maximum size of arrays. Set at **SIZE_MAX-1**. **DC_SCALE_MAX** : The maximum **scale**. Set at **DC_OVERFLOW_MAX-1**. **DC_STRING_MAX** : The maximum length of strings. Set at **DC_OVERFLOW_MAX-1**. **DC_NAME_MAX** : The maximum length of identifiers. Set at **DC_OVERFLOW_MAX-1**. **DC_NUM_MAX** : The maximum length of a number (in decimal digits), which includes digits after the decimal point. Set at **DC_OVERFLOW_MAX-1**. **DC_RAND_MAX** : The maximum integer (inclusive) returned by the **'** command, if dc(1). Set at **2\^DC_LONG_BIT-1**. Exponent : The maximum allowable exponent (positive or negative). Set at **DC_OVERFLOW_MAX**. Number of vars : The maximum number of vars/arrays. Set at **SIZE_MAX-1**. These limits are meant to be effectively non-existent; the limits are so large (at least on 64-bit machines) that there should not be any point at which they become a problem. In fact, memory should be exhausted before these limits should be hit. # ENVIRONMENT VARIABLES dc(1) recognizes the following environment variables: **DC_ENV_ARGS** : This is another way to give command-line arguments to dc(1). They should be in the same format as all other command-line arguments. These are always processed first, so any files given in **DC_ENV_ARGS** will be processed before arguments and files given on the command-line. This gives the user the ability to set up "standard" options and files to be used at every invocation. The most useful thing for such files to contain would be useful functions that the user might want every time dc(1) runs. Another use would be to use the **-e** option to set **scale** to a value other than **0**. The code that parses **DC_ENV_ARGS** will correctly handle quoted arguments, but it does not understand escape sequences. For example, the string **"/home/gavin/some dc file.dc"** will be correctly parsed, but the string **"/home/gavin/some \"dc\" file.dc"** will include the backslashes. The quote parsing will handle either kind of quotes, **'** or **"**. Thus, if you have a file with any number of single quotes in the name, you can use double quotes as the outside quotes, as in **"some 'dc' file.dc"**, and vice versa if you have a file with double quotes. However, handling a file with both kinds of quotes in **DC_ENV_ARGS** is not supported due to the complexity of the parsing, though such files are still supported on the command-line where the parsing is done by the shell. **DC_LINE_LENGTH** : If this environment variable exists and contains an integer that is greater than **1** and is less than **UINT16_MAX** (**2\^16-1**), dc(1) will output lines to that length, including the backslash newline combo. The default line length is **70**. The special value of **0** will disable line length checking and print numbers without regard to line length and without backslashes and newlines. **DC_SIGINT_RESET** : If dc(1) is not in interactive mode (see the **INTERACTIVE MODE** section), then this environment variable has no effect because dc(1) exits on **SIGINT** when not in interactive mode. However, when dc(1) is in interactive mode, then if this environment variable exists and contains an integer, a non-zero value makes dc(1) reset on **SIGINT**, rather than exit, and zero makes dc(1) exit. If this environment variable exists and is *not* an integer, then dc(1) will exit on **SIGINT**. This environment variable overrides the default, which can be queried with the **-h** or **-\-help** options. **DC_TTY_MODE** : If TTY mode is *not* available (see the **TTY MODE** section), then this environment variable has no effect. However, when TTY mode is available, then if this environment variable exists and contains an integer, then a non-zero value makes dc(1) use TTY mode, and zero makes dc(1) not use TTY mode. This environment variable overrides the default, which can be queried with the **-h** or **-\-help** options. **DC_PROMPT** : If TTY mode is *not* available (see the **TTY MODE** section), then this environment variable has no effect. However, when TTY mode is available, then if this environment variable exists and contains an integer, a non-zero value makes dc(1) use a prompt, and zero or a non-integer makes dc(1) not use a prompt. If this environment variable does not exist and **DC_TTY_MODE** does, then the value of the **DC_TTY_MODE** environment variable is used. This environment variable and the **DC_TTY_MODE** environment variable override the default, which can be queried with the **-h** or **-\-help** options. +**DC_EXPR_EXIT** + +: If any expressions or expression files are given on the command-line with + **-e**, **-\-expression**, **-f**, or **-\-file**, then if this environment + variable exists and contains an integer, a non-zero value makes dc(1) exit + after executing the expressions and expression files, and a non-zero value + makes dc(1) not exit. + + This environment variable overrides the default, which can be queried with + the **-h** or **-\-help** options. + # EXIT STATUS dc(1) returns the following exit statuses: **0** : No error. **1** : A math error occurred. This follows standard practice of using **1** for expected errors, since math errors will happen in the process of normal execution. Math errors include divide by **0**, taking the square root of a negative number, using a negative number as a bound for the pseudo-random number generator, attempting to convert a negative number to a hardware integer, overflow when converting a number to a hardware integer, overflow when calculating the size of a number, and attempting to use a non-integer where an integer is required. Converting to a hardware integer happens for the second operand of the power (**\^**), places (**\@**), left shift (**H**), and right shift (**h**) operators. **2** : A parse error occurred. Parse errors include unexpected **EOF**, using an invalid character, failing to find the end of a string or comment, and using a token where it is invalid. **3** : A runtime error occurred. Runtime errors include assigning an invalid number to any global (**ibase**, **obase**, or **scale**), giving a bad expression to a **read()** call, calling **read()** inside of a **read()** call, type errors (including attempting to execute a number), and attempting an operation when the stack has too few elements. **4** : A fatal error occurred. Fatal errors include memory allocation errors, I/O errors, failing to open files, attempting to use files that do not have only ASCII characters (dc(1) only accepts ASCII characters), attempting to open a directory as a file, and giving invalid command-line options. The exit status **4** is special; when a fatal error occurs, dc(1) always exits and returns **4**, no matter what mode dc(1) is in. The other statuses will only be returned when dc(1) is not in interactive mode (see the **INTERACTIVE MODE** section), since dc(1) resets its state (see the **RESET** section) and accepts more input when one of those errors occurs in interactive mode. This is also the case when interactive mode is forced by the **-i** flag or **-\-interactive** option. These exit statuses allow dc(1) to be used in shell scripting with error checking, and its normal behavior can be forced by using the **-i** flag or **-\-interactive** option. # INTERACTIVE MODE Like bc(1), dc(1) has an interactive mode and a non-interactive mode. Interactive mode is turned on automatically when both **stdin** and **stdout** are hooked to a terminal, but the **-i** flag and **-\-interactive** option can turn it on in other situations. In interactive mode, dc(1) attempts to recover from errors (see the **RESET** section), and in normal execution, flushes **stdout** as soon as execution is done for the current input. dc(1) may also reset on **SIGINT** instead of exit, depending on the contents of, or default for, the **DC_SIGINT_RESET** environment variable (see the **ENVIRONMENT VARIABLES** section). # TTY MODE If **stdin**, **stdout**, and **stderr** are all connected to a TTY, then "TTY mode" is considered to be available, and thus, dc(1) can turn on TTY mode, subject to some settings. If there is the environment variable **DC_TTY_MODE** in the environment (see the **ENVIRONMENT VARIABLES** section), then if that environment variable contains a non-zero integer, dc(1) will turn on TTY mode when **stdin**, **stdout**, and **stderr** are all connected to a TTY. If the **DC_TTY_MODE** environment variable exists but is *not* a non-zero integer, then dc(1) will not turn TTY mode on. If the environment variable **DC_TTY_MODE** does *not* exist, the default setting is used. The default setting can be queried with the **-h** or **-\-help** options. TTY mode is different from interactive mode because interactive mode is required in the [bc(1) specification][1], and interactive mode requires only **stdin** and **stdout** to be connected to a terminal. ## Prompt If TTY mode is available, then a prompt can be enabled. Like TTY mode itself, it can be turned on or off with an environment variable: **DC_PROMPT** (see the **ENVIRONMENT VARIABLES** section). If the environment variable **DC_PROMPT** exists and is a non-zero integer, then the prompt is turned on when **stdin**, **stdout**, and **stderr** are connected to a TTY and the **-P** and **-\-no-prompt** options were not used. The read prompt will be turned on under the same conditions, except that the **-R** and **-\-no-read-prompt** options must also not be used. However, if **DC_PROMPT** does not exist, the prompt can be enabled or disabled with the **DC_TTY_MODE** environment variable, the **-P** and **-\-no-prompt** options, and the **-R** and **-\-no-read-prompt** options. See the **ENVIRONMENT VARIABLES** and **OPTIONS** sections for more details. # SIGNAL HANDLING Sending a **SIGINT** will cause dc(1) to do one of two things. If dc(1) is not in interactive mode (see the **INTERACTIVE MODE** section), or the **DC_SIGINT_RESET** environment variable (see the **ENVIRONMENT VARIABLES** section), or its default, is either not an integer or it is zero, dc(1) will exit. However, if dc(1) is in interactive mode, and the **DC_SIGINT_RESET** or its default is an integer and non-zero, then dc(1) will stop executing the current input and reset (see the **RESET** section) upon receiving a **SIGINT**. Note that "current input" can mean one of two things. If dc(1) is processing input from **stdin** in interactive mode, it will ask for more input. If dc(1) is processing input from a file in interactive mode, it will stop processing the file and start processing the next file, if one exists, or ask for input from **stdin** if no other file exists. This means that if a **SIGINT** is sent to dc(1) as it is executing a file, it can seem as though dc(1) did not respond to the signal since it will immediately start executing the next file. This is by design; most files that users execute when interacting with dc(1) have function definitions, which are quick to parse. If a file takes a long time to execute, there may be a bug in that file. The rest of the files could still be executed without problem, allowing the user to continue. **SIGTERM** and **SIGQUIT** cause dc(1) to clean up and exit, and it uses the default handler for all other signals. # LOCALES This dc(1) ships with support for adding error messages for different locales and thus, supports **LC_MESSAGES**. # SEE ALSO bc(1) # STANDARDS The dc(1) utility operators are compliant with the operators in the bc(1) [IEEE Std 1003.1-2017 (“POSIX.1-2017”)][1] specification. # BUGS None are known. Report bugs at https://git.yzena.com/gavin/bc. # AUTHOR Gavin D. Howard and contributors. [1]: https://pubs.opengroup.org/onlinepubs/9699919799/utilities/bc.html diff --git a/contrib/bc/manuals/dc/HN.1 b/contrib/bc/manuals/dc/HN.1 index eb35cb23ff7b..13a39ef26540 100644 --- a/contrib/bc/manuals/dc/HN.1 +++ b/contrib/bc/manuals/dc/HN.1 @@ -1,1519 +1,1532 @@ .\" .\" SPDX-License-Identifier: BSD-2-Clause .\" .\" Copyright (c) 2018-2021 Gavin D. Howard and contributors. .\" .\" Redistribution and use in source and binary forms, with or without .\" modification, are permitted provided that the following conditions are met: .\" .\" * Redistributions of source code must retain the above copyright notice, .\" this list of conditions and the following disclaimer. .\" .\" * Redistributions in binary form must reproduce the above copyright notice, .\" this list of conditions and the following disclaimer in the documentation .\" and/or other materials provided with the distribution. .\" .\" THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" .\" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE .\" IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE .\" ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE .\" LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR .\" CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF .\" SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS .\" INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN .\" CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) .\" ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE .\" POSSIBILITY OF SUCH DAMAGE. .\" .TH "DC" "1" "June 2021" "Gavin D. Howard" "General Commands Manual" .SH Name .PP dc - arbitrary-precision decimal reverse-Polish notation calculator .SH SYNOPSIS .PP \f[B]dc\f[R] [\f[B]-hiPRvVx\f[R]] [\f[B]--version\f[R]] [\f[B]--help\f[R]] [\f[B]--interactive\f[R]] [\f[B]--no-prompt\f[R]] [\f[B]--no-read-prompt\f[R]] [\f[B]--extended-register\f[R]] [\f[B]-e\f[R] \f[I]expr\f[R]] [\f[B]--expression\f[R]=\f[I]expr\f[R]\&...] [\f[B]-f\f[R] \f[I]file\f[R]\&...] [\f[B]--file\f[R]=\f[I]file\f[R]\&...] [\f[I]file\f[R]\&...] .SH DESCRIPTION .PP dc(1) is an arbitrary-precision calculator. It uses a stack (reverse Polish notation) to store numbers and results of computations. Arithmetic operations pop arguments off of the stack and push the results. .PP If no files are given on the command-line, then dc(1) reads from \f[B]stdin\f[R] (see the \f[B]STDIN\f[R] section). Otherwise, those files are processed, and dc(1) will then exit. .PP If a user wants to set up a standard environment, they can use \f[B]DC_ENV_ARGS\f[R] (see the \f[B]ENVIRONMENT VARIABLES\f[R] section). For example, if a user wants the \f[B]scale\f[R] always set to \f[B]10\f[R], they can set \f[B]DC_ENV_ARGS\f[R] to \f[B]-e 10k\f[R], and this dc(1) will always start with a \f[B]scale\f[R] of \f[B]10\f[R]. .SH OPTIONS .PP The following are the options that dc(1) accepts. .TP \f[B]-h\f[R], \f[B]--help\f[R] Prints a usage message and quits. .TP \f[B]-v\f[R], \f[B]-V\f[R], \f[B]--version\f[R] Print the version information (copyright header) and exit. .TP \f[B]-i\f[R], \f[B]--interactive\f[R] Forces interactive mode. (See the \f[B]INTERACTIVE MODE\f[R] section.) .RS .PP This is a \f[B]non-portable extension\f[R]. .RE .TP \f[B]-L\f[R], \f[B]--no-line-length\f[R] Disables line length checking and prints numbers without backslashes and newlines. In other words, this option sets \f[B]BC_LINE_LENGTH\f[R] to \f[B]0\f[R] (see the \f[B]ENVIRONMENT VARIABLES\f[R] section). .RS .PP This is a \f[B]non-portable extension\f[R]. .RE .TP \f[B]-P\f[R], \f[B]--no-prompt\f[R] Disables the prompt in TTY mode. (The prompt is only enabled in TTY mode. See the \f[B]TTY MODE\f[R] section.) This is mostly for those users that do not want a prompt or are not used to having them in dc(1). Most of those users would want to put this option in \f[B]DC_ENV_ARGS\f[R]. .RS .PP These options override the \f[B]DC_PROMPT\f[R] and \f[B]DC_TTY_MODE\f[R] environment variables (see the \f[B]ENVIRONMENT VARIABLES\f[R] section). .PP This is a \f[B]non-portable extension\f[R]. .RE .TP \f[B]-R\f[R], \f[B]--no-read-prompt\f[R] Disables the read prompt in TTY mode. (The read prompt is only enabled in TTY mode. See the \f[B]TTY MODE\f[R] section.) This is mostly for those users that do not want a read prompt or are not used to having them in dc(1). Most of those users would want to put this option in \f[B]BC_ENV_ARGS\f[R] (see the \f[B]ENVIRONMENT VARIABLES\f[R] section). This option is also useful in hash bang lines of dc(1) scripts that prompt for user input. .RS .PP This option does not disable the regular prompt because the read prompt is only used when the \f[B]?\f[R] command is used. .PP These options \f[I]do\f[R] override the \f[B]DC_PROMPT\f[R] and \f[B]DC_TTY_MODE\f[R] environment variables (see the \f[B]ENVIRONMENT VARIABLES\f[R] section), but only for the read prompt. .PP This is a \f[B]non-portable extension\f[R]. .RE .TP \f[B]-x\f[R] \f[B]--extended-register\f[R] Enables extended register mode. See the \f[I]Extended Register Mode\f[R] subsection of the \f[B]REGISTERS\f[R] section for more information. .RS .PP This is a \f[B]non-portable extension\f[R]. .RE .TP \f[B]-z\f[R], \f[B]--leading-zeroes\f[R] Makes bc(1) print all numbers greater than \f[B]-1\f[R] and less than \f[B]1\f[R], and not equal to \f[B]0\f[R], with a leading zero. .RS .PP This can be set for individual numbers with the \f[B]plz(x)\f[R], plznl(x)**, \f[B]pnlz(x)\f[R], and \f[B]pnlznl(x)\f[R] functions in the extended math library (see the \f[B]LIBRARY\f[R] section). .PP This is a \f[B]non-portable extension\f[R]. .RE .TP \f[B]-e\f[R] \f[I]expr\f[R], \f[B]--expression\f[R]=\f[I]expr\f[R] Evaluates \f[I]expr\f[R]. If multiple expressions are given, they are evaluated in order. If files are given as well (see below), the expressions and files are evaluated in the order given. This means that if a file is given before an expression, the file is read in and evaluated first. .RS .PP If this option is given on the command-line (i.e., not in \f[B]DC_ENV_ARGS\f[R], see the \f[B]ENVIRONMENT VARIABLES\f[R] section), then after processing all expressions and files, dc(1) will exit, unless \f[B]-\f[R] (\f[B]stdin\f[R]) was given as an argument at least once to \f[B]-f\f[R] or \f[B]--file\f[R], whether on the command-line or in \f[B]DC_ENV_ARGS\f[R]. However, if any other \f[B]-e\f[R], \f[B]--expression\f[R], \f[B]-f\f[R], or \f[B]--file\f[R] arguments are given after \f[B]-f-\f[R] or equivalent is given, dc(1) will give a fatal error and exit. .PP This is a \f[B]non-portable extension\f[R]. .RE .TP \f[B]-f\f[R] \f[I]file\f[R], \f[B]--file\f[R]=\f[I]file\f[R] Reads in \f[I]file\f[R] and evaluates it, line by line, as though it were read through \f[B]stdin\f[R]. If expressions are also given (see above), the expressions are evaluated in the order given. .RS .PP If this option is given on the command-line (i.e., not in \f[B]DC_ENV_ARGS\f[R], see the \f[B]ENVIRONMENT VARIABLES\f[R] section), then after processing all expressions and files, dc(1) will exit, unless \f[B]-\f[R] (\f[B]stdin\f[R]) was given as an argument at least once to \f[B]-f\f[R] or \f[B]--file\f[R]. However, if any other \f[B]-e\f[R], \f[B]--expression\f[R], \f[B]-f\f[R], or \f[B]--file\f[R] arguments are given after \f[B]-f-\f[R] or equivalent is given, dc(1) will give a fatal error and exit. .PP This is a \f[B]non-portable extension\f[R]. .RE .PP All long options are \f[B]non-portable extensions\f[R]. .SH STDIN .PP If no files are given on the command-line and no files or expressions are given by the \f[B]-f\f[R], \f[B]--file\f[R], \f[B]-e\f[R], or \f[B]--expression\f[R] options, then dc(1) read from \f[B]stdin\f[R]. .PP However, there is a caveat to this. .PP First, \f[B]stdin\f[R] is evaluated a line at a time. The only exception to this is if a string has been finished, but not ended. This means that, except for escaped brackets, all brackets must be balanced before dc(1) parses and executes. .SH STDOUT .PP Any non-error output is written to \f[B]stdout\f[R]. In addition, if history (see the \f[B]HISTORY\f[R] section) and the prompt (see the \f[B]TTY MODE\f[R] section) are enabled, both are output to \f[B]stdout\f[R]. .PP \f[B]Note\f[R]: Unlike other dc(1) implementations, this dc(1) will issue a fatal error (see the \f[B]EXIT STATUS\f[R] section) if it cannot write to \f[B]stdout\f[R], so if \f[B]stdout\f[R] is closed, as in \f[B]dc >&-\f[R], it will quit with an error. This is done so that dc(1) can report problems when \f[B]stdout\f[R] is redirected to a file. .PP If there are scripts that depend on the behavior of other dc(1) implementations, it is recommended that those scripts be changed to redirect \f[B]stdout\f[R] to \f[B]/dev/null\f[R]. .SH STDERR .PP Any error output is written to \f[B]stderr\f[R]. .PP \f[B]Note\f[R]: Unlike other dc(1) implementations, this dc(1) will issue a fatal error (see the \f[B]EXIT STATUS\f[R] section) if it cannot write to \f[B]stderr\f[R], so if \f[B]stderr\f[R] is closed, as in \f[B]dc 2>&-\f[R], it will quit with an error. This is done so that dc(1) can exit with an error code when \f[B]stderr\f[R] is redirected to a file. .PP If there are scripts that depend on the behavior of other dc(1) implementations, it is recommended that those scripts be changed to redirect \f[B]stderr\f[R] to \f[B]/dev/null\f[R]. .SH SYNTAX .PP Each item in the input source code, either a number (see the \f[B]NUMBERS\f[R] section) or a command (see the \f[B]COMMANDS\f[R] section), is processed and executed, in order. Input is processed immediately when entered. .PP \f[B]ibase\f[R] is a register (see the \f[B]REGISTERS\f[R] section) that determines how to interpret constant numbers. It is the \[lq]input\[rq] base, or the number base used for interpreting input numbers. \f[B]ibase\f[R] is initially \f[B]10\f[R]. The max allowable value for \f[B]ibase\f[R] is \f[B]16\f[R]. The min allowable value for \f[B]ibase\f[R] is \f[B]2\f[R]. The max allowable value for \f[B]ibase\f[R] can be queried in dc(1) programs with the \f[B]T\f[R] command. .PP \f[B]obase\f[R] is a register (see the \f[B]REGISTERS\f[R] section) that determines how to output results. It is the \[lq]output\[rq] base, or the number base used for outputting numbers. \f[B]obase\f[R] is initially \f[B]10\f[R]. The max allowable value for \f[B]obase\f[R] is \f[B]DC_BASE_MAX\f[R] and can be queried with the \f[B]U\f[R] command. The min allowable value for \f[B]obase\f[R] is \f[B]0\f[R]. If \f[B]obase\f[R] is \f[B]0\f[R], values are output in scientific notation, and if \f[B]obase\f[R] is \f[B]1\f[R], values are output in engineering notation. Otherwise, values are output in the specified base. .PP Outputting in scientific and engineering notations are \f[B]non-portable extensions\f[R]. .PP The \f[I]scale\f[R] of an expression is the number of digits in the result of the expression right of the decimal point, and \f[B]scale\f[R] is a register (see the \f[B]REGISTERS\f[R] section) that sets the precision of any operations (with exceptions). \f[B]scale\f[R] is initially \f[B]0\f[R]. \f[B]scale\f[R] cannot be negative. The max allowable value for \f[B]scale\f[R] can be queried in dc(1) programs with the \f[B]V\f[R] command. .PP \f[B]seed\f[R] is a register containing the current seed for the pseudo-random number generator. If the current value of \f[B]seed\f[R] is queried and stored, then if it is assigned to \f[B]seed\f[R] later, the pseudo-random number generator is guaranteed to produce the same sequence of pseudo-random numbers that were generated after the value of \f[B]seed\f[R] was first queried. .PP Multiple values assigned to \f[B]seed\f[R] can produce the same sequence of pseudo-random numbers. Likewise, when a value is assigned to \f[B]seed\f[R], it is not guaranteed that querying \f[B]seed\f[R] immediately after will return the same value. In addition, the value of \f[B]seed\f[R] will change after any call to the \f[B]\[cq]\f[R] command or the \f[B]\[lq]\f[R] command that does not get receive a value of \f[B]0\f[R] or \f[B]1\f[R]. The maximum integer returned by the \f[B]\[cq]\f[R] command can be queried with the \f[B]W\f[R] command. .PP \f[B]Note\f[R]: The values returned by the pseudo-random number generator with the \f[B]\[cq]\f[R] and \f[B]\[lq]\f[R] commands are guaranteed to \f[B]NOT\f[R] be cryptographically secure. This is a consequence of using a seeded pseudo-random number generator. However, they \f[I]are\f[R] guaranteed to be reproducible with identical \f[B]seed\f[R] values. This means that the pseudo-random values from dc(1) should only be used where a reproducible stream of pseudo-random numbers is \f[I]ESSENTIAL\f[R]. In any other case, use a non-seeded pseudo-random number generator. .PP The pseudo-random number generator, \f[B]seed\f[R], and all associated operations are \f[B]non-portable extensions\f[R]. .SS Comments .PP Comments go from \f[B]#\f[R] until, and not including, the next newline. This is a \f[B]non-portable extension\f[R]. .SH NUMBERS .PP Numbers are strings made up of digits, uppercase letters up to \f[B]F\f[R], and at most \f[B]1\f[R] period for a radix. Numbers can have up to \f[B]DC_NUM_MAX\f[R] digits. Uppercase letters are equal to \f[B]9\f[R] + their position in the alphabet (i.e., \f[B]A\f[R] equals \f[B]10\f[R], or \f[B]9+1\f[R]). If a digit or letter makes no sense with the current value of \f[B]ibase\f[R], they are set to the value of the highest valid digit in \f[B]ibase\f[R]. .PP Single-character numbers (i.e., \f[B]A\f[R] alone) take the value that they would have if they were valid digits, regardless of the value of \f[B]ibase\f[R]. This means that \f[B]A\f[R] alone always equals decimal \f[B]10\f[R] and \f[B]F\f[R] alone always equals decimal \f[B]15\f[R]. .PP In addition, dc(1) accepts numbers in scientific notation. These have the form \f[B]e\f[R]. The exponent (the portion after the \f[B]e\f[R]) must be an integer. An example is \f[B]1.89237e9\f[R], which is equal to \f[B]1892370000\f[R]. Negative exponents are also allowed, so \f[B]4.2890e_3\f[R] is equal to \f[B]0.0042890\f[R]. .PP \f[B]WARNING\f[R]: Both the number and the exponent in scientific notation are interpreted according to the current \f[B]ibase\f[R], but the number is still multiplied by \f[B]10\[ha]exponent\f[R] regardless of the current \f[B]ibase\f[R]. For example, if \f[B]ibase\f[R] is \f[B]16\f[R] and dc(1) is given the number string \f[B]FFeA\f[R], the resulting decimal number will be \f[B]2550000000000\f[R], and if dc(1) is given the number string \f[B]10e_4\f[R], the resulting decimal number will be \f[B]0.0016\f[R]. .PP Accepting input as scientific notation is a \f[B]non-portable extension\f[R]. .SH COMMANDS .PP The valid commands are listed below. .SS Printing .PP These commands are used for printing. .PP Note that both scientific notation and engineering notation are available for printing numbers. Scientific notation is activated by assigning \f[B]0\f[R] to \f[B]obase\f[R] using \f[B]0o\f[R], and engineering notation is activated by assigning \f[B]1\f[R] to \f[B]obase\f[R] using \f[B]1o\f[R]. To deactivate them, just assign a different value to \f[B]obase\f[R]. .PP Printing numbers in scientific notation and/or engineering notation is a \f[B]non-portable extension\f[R]. .TP \f[B]p\f[R] Prints the value on top of the stack, whether number or string, and prints a newline after. .RS .PP This does not alter the stack. .RE .TP \f[B]n\f[R] Prints the value on top of the stack, whether number or string, and pops it off of the stack. .TP \f[B]P\f[R] Pops a value off the stack. .RS .PP If the value is a number, it is truncated and the absolute value of the result is printed as though \f[B]obase\f[R] is \f[B]256\f[R] and each digit is interpreted as an 8-bit ASCII character, making it a byte stream. .PP If the value is a string, it is printed without a trailing newline. .PP This is a \f[B]non-portable extension\f[R]. .RE .TP \f[B]f\f[R] Prints the entire contents of the stack, in order from newest to oldest, without altering anything. .RS .PP Users should use this command when they get lost. .RE .SS Arithmetic .PP These are the commands used for arithmetic. .TP \f[B]+\f[R] The top two values are popped off the stack, added, and the result is pushed onto the stack. The \f[I]scale\f[R] of the result is equal to the max \f[I]scale\f[R] of both operands. .TP \f[B]-\f[R] The top two values are popped off the stack, subtracted, and the result is pushed onto the stack. The \f[I]scale\f[R] of the result is equal to the max \f[I]scale\f[R] of both operands. .TP \f[B]*\f[R] The top two values are popped off the stack, multiplied, and the result is pushed onto the stack. If \f[B]a\f[R] is the \f[I]scale\f[R] of the first expression and \f[B]b\f[R] is the \f[I]scale\f[R] of the second expression, the \f[I]scale\f[R] of the result is equal to \f[B]min(a+b,max(scale,a,b))\f[R] where \f[B]min()\f[R] and \f[B]max()\f[R] return the obvious values. .TP \f[B]/\f[R] The top two values are popped off the stack, divided, and the result is pushed onto the stack. The \f[I]scale\f[R] of the result is equal to \f[B]scale\f[R]. .RS .PP The first value popped off of the stack must be non-zero. .RE .TP \f[B]%\f[R] The top two values are popped off the stack, remaindered, and the result is pushed onto the stack. .RS .PP Remaindering is equivalent to 1) Computing \f[B]a/b\f[R] to current \f[B]scale\f[R], and 2) Using the result of step 1 to calculate \f[B]a-(a/b)*b\f[R] to \f[I]scale\f[R] \f[B]max(scale+scale(b),scale(a))\f[R]. .PP The first value popped off of the stack must be non-zero. .RE .TP \f[B]\[ti]\f[R] The top two values are popped off the stack, divided and remaindered, and the results (divided first, remainder second) are pushed onto the stack. This is equivalent to \f[B]x y / x y %\f[R] except that \f[B]x\f[R] and \f[B]y\f[R] are only evaluated once. .RS .PP The first value popped off of the stack must be non-zero. .PP This is a \f[B]non-portable extension\f[R]. .RE .TP \f[B]\[ha]\f[R] The top two values are popped off the stack, the second is raised to the power of the first, and the result is pushed onto the stack. The \f[I]scale\f[R] of the result is equal to \f[B]scale\f[R]. .RS .PP The first value popped off of the stack must be an integer, and if that value is negative, the second value popped off of the stack must be non-zero. .RE .TP \f[B]v\f[R] The top value is popped off the stack, its square root is computed, and the result is pushed onto the stack. The \f[I]scale\f[R] of the result is equal to \f[B]scale\f[R]. .RS .PP The value popped off of the stack must be non-negative. .RE .TP \f[B]_\f[R] If this command \f[I]immediately\f[R] precedes a number (i.e., no spaces or other commands), then that number is input as a negative number. .RS .PP Otherwise, the top value on the stack is popped and copied, and the copy is negated and pushed onto the stack. This behavior without a number is a \f[B]non-portable extension\f[R]. .RE .TP \f[B]b\f[R] The top value is popped off the stack, and if it is zero, it is pushed back onto the stack. Otherwise, its absolute value is pushed onto the stack. .RS .PP This is a \f[B]non-portable extension\f[R]. .RE .TP \f[B]|\f[R] The top three values are popped off the stack, a modular exponentiation is computed, and the result is pushed onto the stack. .RS .PP The first value popped is used as the reduction modulus and must be an integer and non-zero. The second value popped is used as the exponent and must be an integer and non-negative. The third value popped is the base and must be an integer. .PP This is a \f[B]non-portable extension\f[R]. .RE .TP \f[B]$\f[R] The top value is popped off the stack and copied, and the copy is truncated and pushed onto the stack. .RS .PP This is a \f[B]non-portable extension\f[R]. .RE .TP \f[B]\[at]\f[R] The top two values are popped off the stack, and the precision of the second is set to the value of the first, whether by truncation or extension. .RS .PP The first value popped off of the stack must be an integer and non-negative. .PP This is a \f[B]non-portable extension\f[R]. .RE .TP \f[B]H\f[R] The top two values are popped off the stack, and the second is shifted left (radix shifted right) to the value of the first. .RS .PP The first value popped off of the stack must be an integer and non-negative. .PP This is a \f[B]non-portable extension\f[R]. .RE .TP \f[B]h\f[R] The top two values are popped off the stack, and the second is shifted right (radix shifted left) to the value of the first. .RS .PP The first value popped off of the stack must be an integer and non-negative. .PP This is a \f[B]non-portable extension\f[R]. .RE .TP \f[B]G\f[R] The top two values are popped off of the stack, they are compared, and a \f[B]1\f[R] is pushed if they are equal, or \f[B]0\f[R] otherwise. .RS .PP This is a \f[B]non-portable extension\f[R]. .RE .TP \f[B]N\f[R] The top value is popped off of the stack, and if it a \f[B]0\f[R], a \f[B]1\f[R] is pushed; otherwise, a \f[B]0\f[R] is pushed. .RS .PP This is a \f[B]non-portable extension\f[R]. .RE .TP \f[B](\f[R] The top two values are popped off of the stack, they are compared, and a \f[B]1\f[R] is pushed if the first is less than the second, or \f[B]0\f[R] otherwise. .RS .PP This is a \f[B]non-portable extension\f[R]. .RE .TP \f[B]{\f[R] The top two values are popped off of the stack, they are compared, and a \f[B]1\f[R] is pushed if the first is less than or equal to the second, or \f[B]0\f[R] otherwise. .RS .PP This is a \f[B]non-portable extension\f[R]. .RE .TP \f[B])\f[R] The top two values are popped off of the stack, they are compared, and a \f[B]1\f[R] is pushed if the first is greater than the second, or \f[B]0\f[R] otherwise. .RS .PP This is a \f[B]non-portable extension\f[R]. .RE .TP \f[B]}\f[R] The top two values are popped off of the stack, they are compared, and a \f[B]1\f[R] is pushed if the first is greater than or equal to the second, or \f[B]0\f[R] otherwise. .RS .PP This is a \f[B]non-portable extension\f[R]. .RE .TP \f[B]M\f[R] The top two values are popped off of the stack. If they are both non-zero, a \f[B]1\f[R] is pushed onto the stack. If either of them is zero, or both of them are, then a \f[B]0\f[R] is pushed onto the stack. .RS .PP This is like the \f[B]&&\f[R] operator in bc(1), and it is \f[I]not\f[R] a short-circuit operator. .PP This is a \f[B]non-portable extension\f[R]. .RE .TP \f[B]m\f[R] The top two values are popped off of the stack. If at least one of them is non-zero, a \f[B]1\f[R] is pushed onto the stack. If both of them are zero, then a \f[B]0\f[R] is pushed onto the stack. .RS .PP This is like the \f[B]||\f[R] operator in bc(1), and it is \f[I]not\f[R] a short-circuit operator. .PP This is a \f[B]non-portable extension\f[R]. .RE .SS Pseudo-Random Number Generator .PP dc(1) has a built-in pseudo-random number generator. These commands query the pseudo-random number generator. (See Parameters for more information about the \f[B]seed\f[R] value that controls the pseudo-random number generator.) .PP The pseudo-random number generator is guaranteed to \f[B]NOT\f[R] be cryptographically secure. .TP \f[B]\[cq]\f[R] Generates an integer between 0 and \f[B]DC_RAND_MAX\f[R], inclusive (see the \f[B]LIMITS\f[R] section). .RS .PP The generated integer is made as unbiased as possible, subject to the limitations of the pseudo-random number generator. .PP This is a \f[B]non-portable extension\f[R]. .RE .TP \f[B]\[lq]\f[R] Pops a value off of the stack, which is used as an \f[B]exclusive\f[R] upper bound on the integer that will be generated. If the bound is negative or is a non-integer, an error is raised, and dc(1) resets (see the \f[B]RESET\f[R] section) while \f[B]seed\f[R] remains unchanged. If the bound is larger than \f[B]DC_RAND_MAX\f[R], the higher bound is honored by generating several pseudo-random integers, multiplying them by appropriate powers of \f[B]DC_RAND_MAX+1\f[R], and adding them together. Thus, the size of integer that can be generated with this command is unbounded. Using this command will change the value of \f[B]seed\f[R], unless the operand is \f[B]0\f[R] or \f[B]1\f[R]. In that case, \f[B]0\f[R] is pushed onto the stack, and \f[B]seed\f[R] is \f[I]not\f[R] changed. .RS .PP The generated integer is made as unbiased as possible, subject to the limitations of the pseudo-random number generator. .PP This is a \f[B]non-portable extension\f[R]. .RE .SS Stack Control .PP These commands control the stack. .TP \f[B]c\f[R] Removes all items from (\[lq]clears\[rq]) the stack. .TP \f[B]d\f[R] Copies the item on top of the stack (\[lq]duplicates\[rq]) and pushes the copy onto the stack. .TP \f[B]r\f[R] Swaps (\[lq]reverses\[rq]) the two top items on the stack. .TP \f[B]R\f[R] Pops (\[lq]removes\[rq]) the top value from the stack. .SS Register Control .PP These commands control registers (see the \f[B]REGISTERS\f[R] section). .TP \f[B]s\f[R]\f[I]r\f[R] Pops the value off the top of the stack and stores it into register \f[I]r\f[R]. .TP \f[B]l\f[R]\f[I]r\f[R] Copies the value in register \f[I]r\f[R] and pushes it onto the stack. This does not alter the contents of \f[I]r\f[R]. .TP \f[B]S\f[R]\f[I]r\f[R] Pops the value off the top of the (main) stack and pushes it onto the stack of register \f[I]r\f[R]. The previous value of the register becomes inaccessible. .TP \f[B]L\f[R]\f[I]r\f[R] Pops the value off the top of the stack for register \f[I]r\f[R] and push it onto the main stack. The previous value in the stack for register \f[I]r\f[R], if any, is now accessible via the \f[B]l\f[R]\f[I]r\f[R] command. .SS Parameters .PP These commands control the values of \f[B]ibase\f[R], \f[B]obase\f[R], \f[B]scale\f[R], and \f[B]seed\f[R]. Also see the \f[B]SYNTAX\f[R] section. .TP \f[B]i\f[R] Pops the value off of the top of the stack and uses it to set \f[B]ibase\f[R], which must be between \f[B]2\f[R] and \f[B]16\f[R], inclusive. .RS .PP If the value on top of the stack has any \f[I]scale\f[R], the \f[I]scale\f[R] is ignored. .RE .TP \f[B]o\f[R] Pops the value off of the top of the stack and uses it to set \f[B]obase\f[R], which must be between \f[B]0\f[R] and \f[B]DC_BASE_MAX\f[R], inclusive (see the \f[B]LIMITS\f[R] section and the \f[B]NUMBERS\f[R] section). .RS .PP If the value on top of the stack has any \f[I]scale\f[R], the \f[I]scale\f[R] is ignored. .RE .TP \f[B]k\f[R] Pops the value off of the top of the stack and uses it to set \f[B]scale\f[R], which must be non-negative. .RS .PP If the value on top of the stack has any \f[I]scale\f[R], the \f[I]scale\f[R] is ignored. .RE .TP \f[B]j\f[R] Pops the value off of the top of the stack and uses it to set \f[B]seed\f[R]. The meaning of \f[B]seed\f[R] is dependent on the current pseudo-random number generator but is guaranteed to not change except for new major versions. .RS .PP The \f[I]scale\f[R] and sign of the value may be significant. .PP If a previously used \f[B]seed\f[R] value is used again, the pseudo-random number generator is guaranteed to produce the same sequence of pseudo-random numbers as it did when the \f[B]seed\f[R] value was previously used. .PP The exact value assigned to \f[B]seed\f[R] is not guaranteed to be returned if the \f[B]J\f[R] command is used. However, if \f[B]seed\f[R] \f[I]does\f[R] return a different value, both values, when assigned to \f[B]seed\f[R], are guaranteed to produce the same sequence of pseudo-random numbers. This means that certain values assigned to \f[B]seed\f[R] will not produce unique sequences of pseudo-random numbers. .PP There is no limit to the length (number of significant decimal digits) or \f[I]scale\f[R] of the value that can be assigned to \f[B]seed\f[R]. .PP This is a \f[B]non-portable extension\f[R]. .RE .TP \f[B]I\f[R] Pushes the current value of \f[B]ibase\f[R] onto the main stack. .TP \f[B]O\f[R] Pushes the current value of \f[B]obase\f[R] onto the main stack. .TP \f[B]K\f[R] Pushes the current value of \f[B]scale\f[R] onto the main stack. .TP \f[B]J\f[R] Pushes the current value of \f[B]seed\f[R] onto the main stack. .RS .PP This is a \f[B]non-portable extension\f[R]. .RE .TP \f[B]T\f[R] Pushes the maximum allowable value of \f[B]ibase\f[R] onto the main stack. .RS .PP This is a \f[B]non-portable extension\f[R]. .RE .TP \f[B]U\f[R] Pushes the maximum allowable value of \f[B]obase\f[R] onto the main stack. .RS .PP This is a \f[B]non-portable extension\f[R]. .RE .TP \f[B]V\f[R] Pushes the maximum allowable value of \f[B]scale\f[R] onto the main stack. .RS .PP This is a \f[B]non-portable extension\f[R]. .RE .TP \f[B]W\f[R] Pushes the maximum (inclusive) integer that can be generated with the \f[B]\[cq]\f[R] pseudo-random number generator command. .RS .PP This is a \f[B]non-portable extension\f[R]. .RE .SS Strings .PP The following commands control strings. .PP dc(1) can work with both numbers and strings, and registers (see the \f[B]REGISTERS\f[R] section) can hold both strings and numbers. dc(1) always knows whether the contents of a register are a string or a number. .PP While arithmetic operations have to have numbers, and will print an error if given a string, other commands accept strings. .PP Strings can also be executed as macros. For example, if the string \f[B][1pR]\f[R] is executed as a macro, then the code \f[B]1pR\f[R] is executed, meaning that the \f[B]1\f[R] will be printed with a newline after and then popped from the stack. .TP \f[B][\f[R]\f[I]characters\f[R]\f[B]]\f[R] Makes a string containing \f[I]characters\f[R] and pushes it onto the stack. .RS .PP If there are brackets (\f[B][\f[R] and \f[B]]\f[R]) in the string, then they must be balanced. Unbalanced brackets can be escaped using a backslash (\f[B]\[rs]\f[R]) character. .PP If there is a backslash character in the string, the character after it (even another backslash) is put into the string verbatim, but the (first) backslash is not. .RE .TP \f[B]a\f[R] The value on top of the stack is popped. .RS .PP If it is a number, it is truncated and its absolute value is taken. The result mod \f[B]256\f[R] is calculated. If that result is \f[B]0\f[R], push an empty string; otherwise, push a one-character string where the character is the result of the mod interpreted as an ASCII character. .PP If it is a string, then a new string is made. If the original string is empty, the new string is empty. If it is not, then the first character of the original string is used to create the new string as a one-character string. The new string is then pushed onto the stack. .PP This is a \f[B]non-portable extension\f[R]. .RE .TP \f[B]x\f[R] Pops a value off of the top of the stack. .RS .PP If it is a number, it is pushed back onto the stack. .PP If it is a string, it is executed as a macro. .PP This behavior is the norm whenever a macro is executed, whether by this command or by the conditional execution commands below. .RE .TP \f[B]>\f[R]\f[I]r\f[R] Pops two values off of the stack that must be numbers and compares them. If the first value is greater than the second, then the contents of register \f[I]r\f[R] are executed. .RS .PP For example, \f[B]0 1>a\f[R] will execute the contents of register \f[B]a\f[R], and \f[B]1 0>a\f[R] will not. .PP If either or both of the values are not numbers, dc(1) will raise an error and reset (see the \f[B]RESET\f[R] section). .RE .TP \f[B]>\f[R]\f[I]r\f[R]\f[B]e\f[R]\f[I]s\f[R] Like the above, but will execute register \f[I]s\f[R] if the comparison fails. .RS .PP If either or both of the values are not numbers, dc(1) will raise an error and reset (see the \f[B]RESET\f[R] section). .PP This is a \f[B]non-portable extension\f[R]. .RE .TP \f[B]!>\f[R]\f[I]r\f[R] Pops two values off of the stack that must be numbers and compares them. If the first value is not greater than the second (less than or equal to), then the contents of register \f[I]r\f[R] are executed. .RS .PP If either or both of the values are not numbers, dc(1) will raise an error and reset (see the \f[B]RESET\f[R] section). .RE .TP \f[B]!>\f[R]\f[I]r\f[R]\f[B]e\f[R]\f[I]s\f[R] Like the above, but will execute register \f[I]s\f[R] if the comparison fails. .RS .PP If either or both of the values are not numbers, dc(1) will raise an error and reset (see the \f[B]RESET\f[R] section). .PP This is a \f[B]non-portable extension\f[R]. .RE .TP \f[B]<\f[R]\f[I]r\f[R] Pops two values off of the stack that must be numbers and compares them. If the first value is less than the second, then the contents of register \f[I]r\f[R] are executed. .RS .PP If either or both of the values are not numbers, dc(1) will raise an error and reset (see the \f[B]RESET\f[R] section). .RE .TP \f[B]<\f[R]\f[I]r\f[R]\f[B]e\f[R]\f[I]s\f[R] Like the above, but will execute register \f[I]s\f[R] if the comparison fails. .RS .PP If either or both of the values are not numbers, dc(1) will raise an error and reset (see the \f[B]RESET\f[R] section). .PP This is a \f[B]non-portable extension\f[R]. .RE .TP \f[B]!<\f[R]\f[I]r\f[R] Pops two values off of the stack that must be numbers and compares them. If the first value is not less than the second (greater than or equal to), then the contents of register \f[I]r\f[R] are executed. .RS .PP If either or both of the values are not numbers, dc(1) will raise an error and reset (see the \f[B]RESET\f[R] section). .RE .TP \f[B]!<\f[R]\f[I]r\f[R]\f[B]e\f[R]\f[I]s\f[R] Like the above, but will execute register \f[I]s\f[R] if the comparison fails. .RS .PP If either or both of the values are not numbers, dc(1) will raise an error and reset (see the \f[B]RESET\f[R] section). .PP This is a \f[B]non-portable extension\f[R]. .RE .TP \f[B]=\f[R]\f[I]r\f[R] Pops two values off of the stack that must be numbers and compares them. If the first value is equal to the second, then the contents of register \f[I]r\f[R] are executed. .RS .PP If either or both of the values are not numbers, dc(1) will raise an error and reset (see the \f[B]RESET\f[R] section). .RE .TP \f[B]=\f[R]\f[I]r\f[R]\f[B]e\f[R]\f[I]s\f[R] Like the above, but will execute register \f[I]s\f[R] if the comparison fails. .RS .PP If either or both of the values are not numbers, dc(1) will raise an error and reset (see the \f[B]RESET\f[R] section). .PP This is a \f[B]non-portable extension\f[R]. .RE .TP \f[B]!=\f[R]\f[I]r\f[R] Pops two values off of the stack that must be numbers and compares them. If the first value is not equal to the second, then the contents of register \f[I]r\f[R] are executed. .RS .PP If either or both of the values are not numbers, dc(1) will raise an error and reset (see the \f[B]RESET\f[R] section). .RE .TP \f[B]!=\f[R]\f[I]r\f[R]\f[B]e\f[R]\f[I]s\f[R] Like the above, but will execute register \f[I]s\f[R] if the comparison fails. .RS .PP If either or both of the values are not numbers, dc(1) will raise an error and reset (see the \f[B]RESET\f[R] section). .PP This is a \f[B]non-portable extension\f[R]. .RE .TP \f[B]?\f[R] Reads a line from the \f[B]stdin\f[R] and executes it. This is to allow macros to request input from users. .TP \f[B]q\f[R] During execution of a macro, this exits the execution of that macro and the execution of the macro that executed it. If there are no macros, or only one macro executing, dc(1) exits. .TP \f[B]Q\f[R] Pops a value from the stack which must be non-negative and is used the number of macro executions to pop off of the execution stack. If the number of levels to pop is greater than the number of executing macros, dc(1) exits. .TP \f[B],\f[R] Pushes the depth of the execution stack onto the stack. The execution stack is the stack of string executions. The number that is pushed onto the stack is exactly as many as is needed to make dc(1) exit with the \f[B]Q\f[R] command, so the sequence \f[B],Q\f[R] will make dc(1) exit. .SS Status .PP These commands query status of the stack or its top value. .TP \f[B]Z\f[R] Pops a value off of the stack. .RS .PP If it is a number, calculates the number of significant decimal digits it has and pushes the result. It will push \f[B]1\f[R] if the argument is \f[B]0\f[R] with no decimal places. .PP If it is a string, pushes the number of characters the string has. .RE .TP \f[B]X\f[R] Pops a value off of the stack. .RS .PP If it is a number, pushes the \f[I]scale\f[R] of the value onto the stack. .PP If it is a string, pushes \f[B]0\f[R]. .RE .TP \f[B]z\f[R] Pushes the current depth of the stack (before execution of this command) onto the stack. .TP \f[B]y\f[R]\f[I]r\f[R] Pushes the current stack depth of the register \f[I]r\f[R] onto the main stack. .RS .PP Because each register has a depth of \f[B]1\f[R] (with the value \f[B]0\f[R] in the top item) when dc(1) starts, dc(1) requires that each register\[cq]s stack must always have at least one item; dc(1) will give an error and reset otherwise (see the \f[B]RESET\f[R] section). This means that this command will never push \f[B]0\f[R]. .PP This is a \f[B]non-portable extension\f[R]. .RE .SS Arrays .PP These commands manipulate arrays. .TP \f[B]:\f[R]\f[I]r\f[R] Pops the top two values off of the stack. The second value will be stored in the array \f[I]r\f[R] (see the \f[B]REGISTERS\f[R] section), indexed by the first value. .TP \f[B];\f[R]\f[I]r\f[R] Pops the value on top of the stack and uses it as an index into the array \f[I]r\f[R]. The selected value is then pushed onto the stack. .TP \f[B]Y\f[R]\f[I]r\f[R] Pushes the length of the array \f[I]r\f[R] onto the stack. .RS .PP This is a \f[B]non-portable extension\f[R]. .RE .SS Global Settings .PP These commands retrieve global settings. These are the only commands that require multiple specific characters, and all of them begin with the letter \f[B]g\f[R]. Only the characters below are allowed after the character \f[B]g\f[R]; any other character produces a parse error (see the \f[B]ERRORS\f[R] section). .TP \f[B]gl\f[R] Pushes the line length set by \f[B]DC_LINE_LENGTH\f[R] (see the \f[B]ENVIRONMENT VARIABLES\f[R] section) onto the stack. .TP \f[B]gz\f[R] Pushes \f[B]0\f[R] onto the stack if the leading zero setting has not been enabled with the \f[B]-z\f[R] or \f[B]--leading-zeroes\f[R] options (see the \f[B]OPTIONS\f[R] section), non-zero otherwise. .SH REGISTERS .PP Registers are names that can store strings, numbers, and arrays. (Number/string registers do not interfere with array registers.) .PP Each register is also its own stack, so the current register value is the top of the stack for the register. All registers, when first referenced, have one value (\f[B]0\f[R]) in their stack, and it is a runtime error to attempt to pop that item off of the register stack. .PP In non-extended register mode, a register name is just the single character that follows any command that needs a register name. The only exceptions are: a newline (\f[B]`\[rs]n'\f[R]) and a left bracket (\f[B]`['\f[R]); it is a parse error for a newline or a left bracket to be used as a register name. .SS Extended Register Mode .PP Unlike most other dc(1) implentations, this dc(1) provides nearly unlimited amounts of registers, if extended register mode is enabled. .PP If extended register mode is enabled (\f[B]-x\f[R] or \f[B]--extended-register\f[R] command-line arguments are given), then normal single character registers are used \f[I]unless\f[R] the character immediately following a command that needs a register name is a space (according to \f[B]isspace()\f[R]) and not a newline (\f[B]`\[rs]n'\f[R]). .PP In that case, the register name is found according to the regex \f[B][a-z][a-z0-9_]*\f[R] (like bc(1) identifiers), and it is a parse error if the next non-space characters do not match that regex. .SH RESET .PP When dc(1) encounters an error or a signal that it has a non-default handler for, it resets. This means that several things happen. .PP First, any macros that are executing are stopped and popped off the stack. The behavior is not unlike that of exceptions in programming languages. Then the execution point is set so that any code waiting to execute (after all macros returned) is skipped. .PP Thus, when dc(1) resets, it skips any remaining code waiting to be executed. Then, if it is interactive mode, and the error was not a fatal error (see the \f[B]EXIT STATUS\f[R] section), it asks for more input; otherwise, it exits with the appropriate return code. .SH PERFORMANCE .PP Most dc(1) implementations use \f[B]char\f[R] types to calculate the value of \f[B]1\f[R] decimal digit at a time, but that can be slow. This dc(1) does something different. .PP It uses large integers to calculate more than \f[B]1\f[R] decimal digit at a time. If built in a environment where \f[B]DC_LONG_BIT\f[R] (see the \f[B]LIMITS\f[R] section) is \f[B]64\f[R], then each integer has \f[B]9\f[R] decimal digits. If built in an environment where \f[B]DC_LONG_BIT\f[R] is \f[B]32\f[R] then each integer has \f[B]4\f[R] decimal digits. This value (the number of decimal digits per large integer) is called \f[B]DC_BASE_DIGS\f[R]. .PP In addition, this dc(1) uses an even larger integer for overflow checking. This integer type depends on the value of \f[B]DC_LONG_BIT\f[R], but is always at least twice as large as the integer type used to store digits. .SH LIMITS .PP The following are the limits on dc(1): .TP \f[B]DC_LONG_BIT\f[R] The number of bits in the \f[B]long\f[R] type in the environment where dc(1) was built. This determines how many decimal digits can be stored in a single large integer (see the \f[B]PERFORMANCE\f[R] section). .TP \f[B]DC_BASE_DIGS\f[R] The number of decimal digits per large integer (see the \f[B]PERFORMANCE\f[R] section). Depends on \f[B]DC_LONG_BIT\f[R]. .TP \f[B]DC_BASE_POW\f[R] The max decimal number that each large integer can store (see \f[B]DC_BASE_DIGS\f[R]) plus \f[B]1\f[R]. Depends on \f[B]DC_BASE_DIGS\f[R]. .TP \f[B]DC_OVERFLOW_MAX\f[R] The max number that the overflow type (see the \f[B]PERFORMANCE\f[R] section) can hold. Depends on \f[B]DC_LONG_BIT\f[R]. .TP \f[B]DC_BASE_MAX\f[R] The maximum output base. Set at \f[B]DC_BASE_POW\f[R]. .TP \f[B]DC_DIM_MAX\f[R] The maximum size of arrays. Set at \f[B]SIZE_MAX-1\f[R]. .TP \f[B]DC_SCALE_MAX\f[R] The maximum \f[B]scale\f[R]. Set at \f[B]DC_OVERFLOW_MAX-1\f[R]. .TP \f[B]DC_STRING_MAX\f[R] The maximum length of strings. Set at \f[B]DC_OVERFLOW_MAX-1\f[R]. .TP \f[B]DC_NAME_MAX\f[R] The maximum length of identifiers. Set at \f[B]DC_OVERFLOW_MAX-1\f[R]. .TP \f[B]DC_NUM_MAX\f[R] The maximum length of a number (in decimal digits), which includes digits after the decimal point. Set at \f[B]DC_OVERFLOW_MAX-1\f[R]. .TP \f[B]DC_RAND_MAX\f[R] The maximum integer (inclusive) returned by the \f[B]\[cq]\f[R] command, if dc(1). Set at \f[B]2\[ha]DC_LONG_BIT-1\f[R]. .TP Exponent The maximum allowable exponent (positive or negative). Set at \f[B]DC_OVERFLOW_MAX\f[R]. .TP Number of vars The maximum number of vars/arrays. Set at \f[B]SIZE_MAX-1\f[R]. .PP These limits are meant to be effectively non-existent; the limits are so large (at least on 64-bit machines) that there should not be any point at which they become a problem. In fact, memory should be exhausted before these limits should be hit. .SH ENVIRONMENT VARIABLES .PP dc(1) recognizes the following environment variables: .TP \f[B]DC_ENV_ARGS\f[R] This is another way to give command-line arguments to dc(1). They should be in the same format as all other command-line arguments. These are always processed first, so any files given in \f[B]DC_ENV_ARGS\f[R] will be processed before arguments and files given on the command-line. This gives the user the ability to set up \[lq]standard\[rq] options and files to be used at every invocation. The most useful thing for such files to contain would be useful functions that the user might want every time dc(1) runs. Another use would be to use the \f[B]-e\f[R] option to set \f[B]scale\f[R] to a value other than \f[B]0\f[R]. .RS .PP The code that parses \f[B]DC_ENV_ARGS\f[R] will correctly handle quoted arguments, but it does not understand escape sequences. For example, the string \f[B]\[lq]/home/gavin/some dc file.dc\[rq]\f[R] will be correctly parsed, but the string \f[B]\[lq]/home/gavin/some \[dq]dc\[dq] file.dc\[rq]\f[R] will include the backslashes. .PP The quote parsing will handle either kind of quotes, \f[B]\[cq]\f[R] or \f[B]\[lq]\f[R]. Thus, if you have a file with any number of single quotes in the name, you can use double quotes as the outside quotes, as in \f[B]\[lq]some `dc' file.dc\[rq]\f[R], and vice versa if you have a file with double quotes. However, handling a file with both kinds of quotes in \f[B]DC_ENV_ARGS\f[R] is not supported due to the complexity of the parsing, though such files are still supported on the command-line where the parsing is done by the shell. .RE .TP \f[B]DC_LINE_LENGTH\f[R] If this environment variable exists and contains an integer that is greater than \f[B]1\f[R] and is less than \f[B]UINT16_MAX\f[R] (\f[B]2\[ha]16-1\f[R]), dc(1) will output lines to that length, including the backslash newline combo. The default line length is \f[B]70\f[R]. .RS .PP The special value of \f[B]0\f[R] will disable line length checking and print numbers without regard to line length and without backslashes and newlines. .RE .TP \f[B]DC_SIGINT_RESET\f[R] If dc(1) is not in interactive mode (see the \f[B]INTERACTIVE MODE\f[R] section), then this environment variable has no effect because dc(1) exits on \f[B]SIGINT\f[R] when not in interactive mode. .RS .PP However, when dc(1) is in interactive mode, then if this environment variable exists and contains an integer, a non-zero value makes dc(1) reset on \f[B]SIGINT\f[R], rather than exit, and zero makes dc(1) exit. If this environment variable exists and is \f[I]not\f[R] an integer, then dc(1) will exit on \f[B]SIGINT\f[R]. .PP This environment variable overrides the default, which can be queried with the \f[B]-h\f[R] or \f[B]--help\f[R] options. .RE .TP \f[B]DC_TTY_MODE\f[R] If TTY mode is \f[I]not\f[R] available (see the \f[B]TTY MODE\f[R] section), then this environment variable has no effect. .RS .PP However, when TTY mode is available, then if this environment variable exists and contains an integer, then a non-zero value makes dc(1) use TTY mode, and zero makes dc(1) not use TTY mode. .PP This environment variable overrides the default, which can be queried with the \f[B]-h\f[R] or \f[B]--help\f[R] options. .RE .TP \f[B]DC_PROMPT\f[R] If TTY mode is \f[I]not\f[R] available (see the \f[B]TTY MODE\f[R] section), then this environment variable has no effect. .RS .PP However, when TTY mode is available, then if this environment variable exists and contains an integer, a non-zero value makes dc(1) use a prompt, and zero or a non-integer makes dc(1) not use a prompt. If this environment variable does not exist and \f[B]DC_TTY_MODE\f[R] does, then the value of the \f[B]DC_TTY_MODE\f[R] environment variable is used. .PP This environment variable and the \f[B]DC_TTY_MODE\f[R] environment variable override the default, which can be queried with the \f[B]-h\f[R] or \f[B]--help\f[R] options. .RE +.TP +\f[B]DC_EXPR_EXIT\f[R] +If any expressions or expression files are given on the command-line +with \f[B]-e\f[R], \f[B]--expression\f[R], \f[B]-f\f[R], or +\f[B]--file\f[R], then if this environment variable exists and contains +an integer, a non-zero value makes dc(1) exit after executing the +expressions and expression files, and a non-zero value makes dc(1) not +exit. +.RS +.PP +This environment variable overrides the default, which can be queried +with the \f[B]-h\f[R] or \f[B]--help\f[R] options. +.RE .SH EXIT STATUS .PP dc(1) returns the following exit statuses: .TP \f[B]0\f[R] No error. .TP \f[B]1\f[R] A math error occurred. This follows standard practice of using \f[B]1\f[R] for expected errors, since math errors will happen in the process of normal execution. .RS .PP Math errors include divide by \f[B]0\f[R], taking the square root of a negative number, using a negative number as a bound for the pseudo-random number generator, attempting to convert a negative number to a hardware integer, overflow when converting a number to a hardware integer, overflow when calculating the size of a number, and attempting to use a non-integer where an integer is required. .PP Converting to a hardware integer happens for the second operand of the power (\f[B]\[ha]\f[R]), places (\f[B]\[at]\f[R]), left shift (\f[B]H\f[R]), and right shift (\f[B]h\f[R]) operators. .RE .TP \f[B]2\f[R] A parse error occurred. .RS .PP Parse errors include unexpected \f[B]EOF\f[R], using an invalid character, failing to find the end of a string or comment, and using a token where it is invalid. .RE .TP \f[B]3\f[R] A runtime error occurred. .RS .PP Runtime errors include assigning an invalid number to any global (\f[B]ibase\f[R], \f[B]obase\f[R], or \f[B]scale\f[R]), giving a bad expression to a \f[B]read()\f[R] call, calling \f[B]read()\f[R] inside of a \f[B]read()\f[R] call, type errors (including attempting to execute a number), and attempting an operation when the stack has too few elements. .RE .TP \f[B]4\f[R] A fatal error occurred. .RS .PP Fatal errors include memory allocation errors, I/O errors, failing to open files, attempting to use files that do not have only ASCII characters (dc(1) only accepts ASCII characters), attempting to open a directory as a file, and giving invalid command-line options. .RE .PP The exit status \f[B]4\f[R] is special; when a fatal error occurs, dc(1) always exits and returns \f[B]4\f[R], no matter what mode dc(1) is in. .PP The other statuses will only be returned when dc(1) is not in interactive mode (see the \f[B]INTERACTIVE MODE\f[R] section), since dc(1) resets its state (see the \f[B]RESET\f[R] section) and accepts more input when one of those errors occurs in interactive mode. This is also the case when interactive mode is forced by the \f[B]-i\f[R] flag or \f[B]--interactive\f[R] option. .PP These exit statuses allow dc(1) to be used in shell scripting with error checking, and its normal behavior can be forced by using the \f[B]-i\f[R] flag or \f[B]--interactive\f[R] option. .SH INTERACTIVE MODE .PP Like bc(1), dc(1) has an interactive mode and a non-interactive mode. Interactive mode is turned on automatically when both \f[B]stdin\f[R] and \f[B]stdout\f[R] are hooked to a terminal, but the \f[B]-i\f[R] flag and \f[B]--interactive\f[R] option can turn it on in other situations. .PP In interactive mode, dc(1) attempts to recover from errors (see the \f[B]RESET\f[R] section), and in normal execution, flushes \f[B]stdout\f[R] as soon as execution is done for the current input. dc(1) may also reset on \f[B]SIGINT\f[R] instead of exit, depending on the contents of, or default for, the \f[B]DC_SIGINT_RESET\f[R] environment variable (see the \f[B]ENVIRONMENT VARIABLES\f[R] section). .SH TTY MODE .PP If \f[B]stdin\f[R], \f[B]stdout\f[R], and \f[B]stderr\f[R] are all connected to a TTY, then \[lq]TTY mode\[rq] is considered to be available, and thus, dc(1) can turn on TTY mode, subject to some settings. .PP If there is the environment variable \f[B]DC_TTY_MODE\f[R] in the environment (see the \f[B]ENVIRONMENT VARIABLES\f[R] section), then if that environment variable contains a non-zero integer, dc(1) will turn on TTY mode when \f[B]stdin\f[R], \f[B]stdout\f[R], and \f[B]stderr\f[R] are all connected to a TTY. If the \f[B]DC_TTY_MODE\f[R] environment variable exists but is \f[I]not\f[R] a non-zero integer, then dc(1) will not turn TTY mode on. .PP If the environment variable \f[B]DC_TTY_MODE\f[R] does \f[I]not\f[R] exist, the default setting is used. The default setting can be queried with the \f[B]-h\f[R] or \f[B]--help\f[R] options. .PP TTY mode is different from interactive mode because interactive mode is required in the bc(1) specification (https://pubs.opengroup.org/onlinepubs/9699919799/utilities/bc.html), and interactive mode requires only \f[B]stdin\f[R] and \f[B]stdout\f[R] to be connected to a terminal. .SS Prompt .PP If TTY mode is available, then a prompt can be enabled. Like TTY mode itself, it can be turned on or off with an environment variable: \f[B]DC_PROMPT\f[R] (see the \f[B]ENVIRONMENT VARIABLES\f[R] section). .PP If the environment variable \f[B]DC_PROMPT\f[R] exists and is a non-zero integer, then the prompt is turned on when \f[B]stdin\f[R], \f[B]stdout\f[R], and \f[B]stderr\f[R] are connected to a TTY and the \f[B]-P\f[R] and \f[B]--no-prompt\f[R] options were not used. The read prompt will be turned on under the same conditions, except that the \f[B]-R\f[R] and \f[B]--no-read-prompt\f[R] options must also not be used. .PP However, if \f[B]DC_PROMPT\f[R] does not exist, the prompt can be enabled or disabled with the \f[B]DC_TTY_MODE\f[R] environment variable, the \f[B]-P\f[R] and \f[B]--no-prompt\f[R] options, and the \f[B]-R\f[R] and \f[B]--no-read-prompt\f[R] options. See the \f[B]ENVIRONMENT VARIABLES\f[R] and \f[B]OPTIONS\f[R] sections for more details. .SH SIGNAL HANDLING .PP Sending a \f[B]SIGINT\f[R] will cause dc(1) to do one of two things. .PP If dc(1) is not in interactive mode (see the \f[B]INTERACTIVE MODE\f[R] section), or the \f[B]DC_SIGINT_RESET\f[R] environment variable (see the \f[B]ENVIRONMENT VARIABLES\f[R] section), or its default, is either not an integer or it is zero, dc(1) will exit. .PP However, if dc(1) is in interactive mode, and the \f[B]DC_SIGINT_RESET\f[R] or its default is an integer and non-zero, then dc(1) will stop executing the current input and reset (see the \f[B]RESET\f[R] section) upon receiving a \f[B]SIGINT\f[R]. .PP Note that \[lq]current input\[rq] can mean one of two things. If dc(1) is processing input from \f[B]stdin\f[R] in interactive mode, it will ask for more input. If dc(1) is processing input from a file in interactive mode, it will stop processing the file and start processing the next file, if one exists, or ask for input from \f[B]stdin\f[R] if no other file exists. .PP This means that if a \f[B]SIGINT\f[R] is sent to dc(1) as it is executing a file, it can seem as though dc(1) did not respond to the signal since it will immediately start executing the next file. This is by design; most files that users execute when interacting with dc(1) have function definitions, which are quick to parse. If a file takes a long time to execute, there may be a bug in that file. The rest of the files could still be executed without problem, allowing the user to continue. .PP \f[B]SIGTERM\f[R] and \f[B]SIGQUIT\f[R] cause dc(1) to clean up and exit, and it uses the default handler for all other signals. .SH SEE ALSO .PP bc(1) .SH STANDARDS .PP The dc(1) utility operators are compliant with the operators in the bc(1) IEEE Std 1003.1-2017 (\[lq]POSIX.1-2017\[rq]) (https://pubs.opengroup.org/onlinepubs/9699919799/utilities/bc.html) specification. .SH BUGS .PP None are known. Report bugs at https://git.yzena.com/gavin/bc. .SH AUTHOR .PP Gavin D. Howard and contributors. diff --git a/contrib/bc/manuals/dc/HN.1.md b/contrib/bc/manuals/dc/HN.1.md index 70c962624833..47c2a0330ae9 100644 --- a/contrib/bc/manuals/dc/HN.1.md +++ b/contrib/bc/manuals/dc/HN.1.md @@ -1,1356 +1,1367 @@ # Name dc - arbitrary-precision decimal reverse-Polish notation calculator # SYNOPSIS **dc** [**-hiPRvVx**] [**-\-version**] [**-\-help**] [**-\-interactive**] [**-\-no-prompt**] [**-\-no-read-prompt**] [**-\-extended-register**] [**-e** *expr*] [**-\-expression**=*expr*...] [**-f** *file*...] [**-\-file**=*file*...] [*file*...] # DESCRIPTION dc(1) is an arbitrary-precision calculator. It uses a stack (reverse Polish notation) to store numbers and results of computations. Arithmetic operations pop arguments off of the stack and push the results. If no files are given on the command-line, then dc(1) reads from **stdin** (see the **STDIN** section). Otherwise, those files are processed, and dc(1) will then exit. If a user wants to set up a standard environment, they can use **DC_ENV_ARGS** (see the **ENVIRONMENT VARIABLES** section). For example, if a user wants the **scale** always set to **10**, they can set **DC_ENV_ARGS** to **-e 10k**, and this dc(1) will always start with a **scale** of **10**. # OPTIONS The following are the options that dc(1) accepts. **-h**, **-\-help** : Prints a usage message and quits. **-v**, **-V**, **-\-version** : Print the version information (copyright header) and exit. **-i**, **-\-interactive** : Forces interactive mode. (See the **INTERACTIVE MODE** section.) This is a **non-portable extension**. **-L**, **-\-no-line-length** : Disables line length checking and prints numbers without backslashes and newlines. In other words, this option sets **BC_LINE_LENGTH** to **0** (see the **ENVIRONMENT VARIABLES** section). This is a **non-portable extension**. **-P**, **-\-no-prompt** : Disables the prompt in TTY mode. (The prompt is only enabled in TTY mode. See the **TTY MODE** section.) This is mostly for those users that do not want a prompt or are not used to having them in dc(1). Most of those users would want to put this option in **DC_ENV_ARGS**. These options override the **DC_PROMPT** and **DC_TTY_MODE** environment variables (see the **ENVIRONMENT VARIABLES** section). This is a **non-portable extension**. **-R**, **-\-no-read-prompt** : Disables the read prompt in TTY mode. (The read prompt is only enabled in TTY mode. See the **TTY MODE** section.) This is mostly for those users that do not want a read prompt or are not used to having them in dc(1). Most of those users would want to put this option in **BC_ENV_ARGS** (see the **ENVIRONMENT VARIABLES** section). This option is also useful in hash bang lines of dc(1) scripts that prompt for user input. This option does not disable the regular prompt because the read prompt is only used when the **?** command is used. These options *do* override the **DC_PROMPT** and **DC_TTY_MODE** environment variables (see the **ENVIRONMENT VARIABLES** section), but only for the read prompt. This is a **non-portable extension**. **-x** **-\-extended-register** : Enables extended register mode. See the *Extended Register Mode* subsection of the **REGISTERS** section for more information. This is a **non-portable extension**. **-z**, **-\-leading-zeroes** : Makes bc(1) print all numbers greater than **-1** and less than **1**, and not equal to **0**, with a leading zero. This can be set for individual numbers with the **plz(x)**, plznl(x)**, **pnlz(x)**, and **pnlznl(x)** functions in the extended math library (see the **LIBRARY** section). This is a **non-portable extension**. **-e** *expr*, **-\-expression**=*expr* : Evaluates *expr*. If multiple expressions are given, they are evaluated in order. If files are given as well (see below), the expressions and files are evaluated in the order given. This means that if a file is given before an expression, the file is read in and evaluated first. If this option is given on the command-line (i.e., not in **DC_ENV_ARGS**, see the **ENVIRONMENT VARIABLES** section), then after processing all expressions and files, dc(1) will exit, unless **-** (**stdin**) was given as an argument at least once to **-f** or **-\-file**, whether on the command-line or in **DC_ENV_ARGS**. However, if any other **-e**, **-\-expression**, **-f**, or **-\-file** arguments are given after **-f-** or equivalent is given, dc(1) will give a fatal error and exit. This is a **non-portable extension**. **-f** *file*, **-\-file**=*file* : Reads in *file* and evaluates it, line by line, as though it were read through **stdin**. If expressions are also given (see above), the expressions are evaluated in the order given. If this option is given on the command-line (i.e., not in **DC_ENV_ARGS**, see the **ENVIRONMENT VARIABLES** section), then after processing all expressions and files, dc(1) will exit, unless **-** (**stdin**) was given as an argument at least once to **-f** or **-\-file**. However, if any other **-e**, **-\-expression**, **-f**, or **-\-file** arguments are given after **-f-** or equivalent is given, dc(1) will give a fatal error and exit. This is a **non-portable extension**. All long options are **non-portable extensions**. # STDIN If no files are given on the command-line and no files or expressions are given by the **-f**, **-\-file**, **-e**, or **-\-expression** options, then dc(1) read from **stdin**. However, there is a caveat to this. First, **stdin** is evaluated a line at a time. The only exception to this is if a string has been finished, but not ended. This means that, except for escaped brackets, all brackets must be balanced before dc(1) parses and executes. # STDOUT Any non-error output is written to **stdout**. In addition, if history (see the **HISTORY** section) and the prompt (see the **TTY MODE** section) are enabled, both are output to **stdout**. **Note**: Unlike other dc(1) implementations, this dc(1) will issue a fatal error (see the **EXIT STATUS** section) if it cannot write to **stdout**, so if **stdout** is closed, as in **dc >&-**, it will quit with an error. This is done so that dc(1) can report problems when **stdout** is redirected to a file. If there are scripts that depend on the behavior of other dc(1) implementations, it is recommended that those scripts be changed to redirect **stdout** to **/dev/null**. # STDERR Any error output is written to **stderr**. **Note**: Unlike other dc(1) implementations, this dc(1) will issue a fatal error (see the **EXIT STATUS** section) if it cannot write to **stderr**, so if **stderr** is closed, as in **dc 2>&-**, it will quit with an error. This is done so that dc(1) can exit with an error code when **stderr** is redirected to a file. If there are scripts that depend on the behavior of other dc(1) implementations, it is recommended that those scripts be changed to redirect **stderr** to **/dev/null**. # SYNTAX Each item in the input source code, either a number (see the **NUMBERS** section) or a command (see the **COMMANDS** section), is processed and executed, in order. Input is processed immediately when entered. **ibase** is a register (see the **REGISTERS** section) that determines how to interpret constant numbers. It is the "input" base, or the number base used for interpreting input numbers. **ibase** is initially **10**. The max allowable value for **ibase** is **16**. The min allowable value for **ibase** is **2**. The max allowable value for **ibase** can be queried in dc(1) programs with the **T** command. **obase** is a register (see the **REGISTERS** section) that determines how to output results. It is the "output" base, or the number base used for outputting numbers. **obase** is initially **10**. The max allowable value for **obase** is **DC_BASE_MAX** and can be queried with the **U** command. The min allowable value for **obase** is **0**. If **obase** is **0**, values are output in scientific notation, and if **obase** is **1**, values are output in engineering notation. Otherwise, values are output in the specified base. Outputting in scientific and engineering notations are **non-portable extensions**. The *scale* of an expression is the number of digits in the result of the expression right of the decimal point, and **scale** is a register (see the **REGISTERS** section) that sets the precision of any operations (with exceptions). **scale** is initially **0**. **scale** cannot be negative. The max allowable value for **scale** can be queried in dc(1) programs with the **V** command. **seed** is a register containing the current seed for the pseudo-random number generator. If the current value of **seed** is queried and stored, then if it is assigned to **seed** later, the pseudo-random number generator is guaranteed to produce the same sequence of pseudo-random numbers that were generated after the value of **seed** was first queried. Multiple values assigned to **seed** can produce the same sequence of pseudo-random numbers. Likewise, when a value is assigned to **seed**, it is not guaranteed that querying **seed** immediately after will return the same value. In addition, the value of **seed** will change after any call to the **'** command or the **"** command that does not get receive a value of **0** or **1**. The maximum integer returned by the **'** command can be queried with the **W** command. **Note**: The values returned by the pseudo-random number generator with the **'** and **"** commands are guaranteed to **NOT** be cryptographically secure. This is a consequence of using a seeded pseudo-random number generator. However, they *are* guaranteed to be reproducible with identical **seed** values. This means that the pseudo-random values from dc(1) should only be used where a reproducible stream of pseudo-random numbers is *ESSENTIAL*. In any other case, use a non-seeded pseudo-random number generator. The pseudo-random number generator, **seed**, and all associated operations are **non-portable extensions**. ## Comments Comments go from **#** until, and not including, the next newline. This is a **non-portable extension**. # NUMBERS Numbers are strings made up of digits, uppercase letters up to **F**, and at most **1** period for a radix. Numbers can have up to **DC_NUM_MAX** digits. Uppercase letters are equal to **9** + their position in the alphabet (i.e., **A** equals **10**, or **9+1**). If a digit or letter makes no sense with the current value of **ibase**, they are set to the value of the highest valid digit in **ibase**. Single-character numbers (i.e., **A** alone) take the value that they would have if they were valid digits, regardless of the value of **ibase**. This means that **A** alone always equals decimal **10** and **F** alone always equals decimal **15**. In addition, dc(1) accepts numbers in scientific notation. These have the form **\e\**. The exponent (the portion after the **e**) must be an integer. An example is **1.89237e9**, which is equal to **1892370000**. Negative exponents are also allowed, so **4.2890e_3** is equal to **0.0042890**. **WARNING**: Both the number and the exponent in scientific notation are interpreted according to the current **ibase**, but the number is still multiplied by **10\^exponent** regardless of the current **ibase**. For example, if **ibase** is **16** and dc(1) is given the number string **FFeA**, the resulting decimal number will be **2550000000000**, and if dc(1) is given the number string **10e_4**, the resulting decimal number will be **0.0016**. Accepting input as scientific notation is a **non-portable extension**. # COMMANDS The valid commands are listed below. ## Printing These commands are used for printing. Note that both scientific notation and engineering notation are available for printing numbers. Scientific notation is activated by assigning **0** to **obase** using **0o**, and engineering notation is activated by assigning **1** to **obase** using **1o**. To deactivate them, just assign a different value to **obase**. Printing numbers in scientific notation and/or engineering notation is a **non-portable extension**. **p** : Prints the value on top of the stack, whether number or string, and prints a newline after. This does not alter the stack. **n** : Prints the value on top of the stack, whether number or string, and pops it off of the stack. **P** : Pops a value off the stack. If the value is a number, it is truncated and the absolute value of the result is printed as though **obase** is **256** and each digit is interpreted as an 8-bit ASCII character, making it a byte stream. If the value is a string, it is printed without a trailing newline. This is a **non-portable extension**. **f** : Prints the entire contents of the stack, in order from newest to oldest, without altering anything. Users should use this command when they get lost. ## Arithmetic These are the commands used for arithmetic. **+** : The top two values are popped off the stack, added, and the result is pushed onto the stack. The *scale* of the result is equal to the max *scale* of both operands. **-** : The top two values are popped off the stack, subtracted, and the result is pushed onto the stack. The *scale* of the result is equal to the max *scale* of both operands. **\*** : The top two values are popped off the stack, multiplied, and the result is pushed onto the stack. If **a** is the *scale* of the first expression and **b** is the *scale* of the second expression, the *scale* of the result is equal to **min(a+b,max(scale,a,b))** where **min()** and **max()** return the obvious values. **/** : The top two values are popped off the stack, divided, and the result is pushed onto the stack. The *scale* of the result is equal to **scale**. The first value popped off of the stack must be non-zero. **%** : The top two values are popped off the stack, remaindered, and the result is pushed onto the stack. Remaindering is equivalent to 1) Computing **a/b** to current **scale**, and 2) Using the result of step 1 to calculate **a-(a/b)\*b** to *scale* **max(scale+scale(b),scale(a))**. The first value popped off of the stack must be non-zero. **~** : The top two values are popped off the stack, divided and remaindered, and the results (divided first, remainder second) are pushed onto the stack. This is equivalent to **x y / x y %** except that **x** and **y** are only evaluated once. The first value popped off of the stack must be non-zero. This is a **non-portable extension**. **\^** : The top two values are popped off the stack, the second is raised to the power of the first, and the result is pushed onto the stack. The *scale* of the result is equal to **scale**. The first value popped off of the stack must be an integer, and if that value is negative, the second value popped off of the stack must be non-zero. **v** : The top value is popped off the stack, its square root is computed, and the result is pushed onto the stack. The *scale* of the result is equal to **scale**. The value popped off of the stack must be non-negative. **\_** : If this command *immediately* precedes a number (i.e., no spaces or other commands), then that number is input as a negative number. Otherwise, the top value on the stack is popped and copied, and the copy is negated and pushed onto the stack. This behavior without a number is a **non-portable extension**. **b** : The top value is popped off the stack, and if it is zero, it is pushed back onto the stack. Otherwise, its absolute value is pushed onto the stack. This is a **non-portable extension**. **|** : The top three values are popped off the stack, a modular exponentiation is computed, and the result is pushed onto the stack. The first value popped is used as the reduction modulus and must be an integer and non-zero. The second value popped is used as the exponent and must be an integer and non-negative. The third value popped is the base and must be an integer. This is a **non-portable extension**. **\$** : The top value is popped off the stack and copied, and the copy is truncated and pushed onto the stack. This is a **non-portable extension**. **\@** : The top two values are popped off the stack, and the precision of the second is set to the value of the first, whether by truncation or extension. The first value popped off of the stack must be an integer and non-negative. This is a **non-portable extension**. **H** : The top two values are popped off the stack, and the second is shifted left (radix shifted right) to the value of the first. The first value popped off of the stack must be an integer and non-negative. This is a **non-portable extension**. **h** : The top two values are popped off the stack, and the second is shifted right (radix shifted left) to the value of the first. The first value popped off of the stack must be an integer and non-negative. This is a **non-portable extension**. **G** : The top two values are popped off of the stack, they are compared, and a **1** is pushed if they are equal, or **0** otherwise. This is a **non-portable extension**. **N** : The top value is popped off of the stack, and if it a **0**, a **1** is pushed; otherwise, a **0** is pushed. This is a **non-portable extension**. **(** : The top two values are popped off of the stack, they are compared, and a **1** is pushed if the first is less than the second, or **0** otherwise. This is a **non-portable extension**. **{** : The top two values are popped off of the stack, they are compared, and a **1** is pushed if the first is less than or equal to the second, or **0** otherwise. This is a **non-portable extension**. **)** : The top two values are popped off of the stack, they are compared, and a **1** is pushed if the first is greater than the second, or **0** otherwise. This is a **non-portable extension**. **}** : The top two values are popped off of the stack, they are compared, and a **1** is pushed if the first is greater than or equal to the second, or **0** otherwise. This is a **non-portable extension**. **M** : The top two values are popped off of the stack. If they are both non-zero, a **1** is pushed onto the stack. If either of them is zero, or both of them are, then a **0** is pushed onto the stack. This is like the **&&** operator in bc(1), and it is *not* a short-circuit operator. This is a **non-portable extension**. **m** : The top two values are popped off of the stack. If at least one of them is non-zero, a **1** is pushed onto the stack. If both of them are zero, then a **0** is pushed onto the stack. This is like the **||** operator in bc(1), and it is *not* a short-circuit operator. This is a **non-portable extension**. ## Pseudo-Random Number Generator dc(1) has a built-in pseudo-random number generator. These commands query the pseudo-random number generator. (See Parameters for more information about the **seed** value that controls the pseudo-random number generator.) The pseudo-random number generator is guaranteed to **NOT** be cryptographically secure. **'** : Generates an integer between 0 and **DC_RAND_MAX**, inclusive (see the **LIMITS** section). The generated integer is made as unbiased as possible, subject to the limitations of the pseudo-random number generator. This is a **non-portable extension**. **"** : Pops a value off of the stack, which is used as an **exclusive** upper bound on the integer that will be generated. If the bound is negative or is a non-integer, an error is raised, and dc(1) resets (see the **RESET** section) while **seed** remains unchanged. If the bound is larger than **DC_RAND_MAX**, the higher bound is honored by generating several pseudo-random integers, multiplying them by appropriate powers of **DC_RAND_MAX+1**, and adding them together. Thus, the size of integer that can be generated with this command is unbounded. Using this command will change the value of **seed**, unless the operand is **0** or **1**. In that case, **0** is pushed onto the stack, and **seed** is *not* changed. The generated integer is made as unbiased as possible, subject to the limitations of the pseudo-random number generator. This is a **non-portable extension**. ## Stack Control These commands control the stack. **c** : Removes all items from ("clears") the stack. **d** : Copies the item on top of the stack ("duplicates") and pushes the copy onto the stack. **r** : Swaps ("reverses") the two top items on the stack. **R** : Pops ("removes") the top value from the stack. ## Register Control These commands control registers (see the **REGISTERS** section). **s**_r_ : Pops the value off the top of the stack and stores it into register *r*. **l**_r_ : Copies the value in register *r* and pushes it onto the stack. This does not alter the contents of *r*. **S**_r_ : Pops the value off the top of the (main) stack and pushes it onto the stack of register *r*. The previous value of the register becomes inaccessible. **L**_r_ : Pops the value off the top of the stack for register *r* and push it onto the main stack. The previous value in the stack for register *r*, if any, is now accessible via the **l**_r_ command. ## Parameters These commands control the values of **ibase**, **obase**, **scale**, and **seed**. Also see the **SYNTAX** section. **i** : Pops the value off of the top of the stack and uses it to set **ibase**, which must be between **2** and **16**, inclusive. If the value on top of the stack has any *scale*, the *scale* is ignored. **o** : Pops the value off of the top of the stack and uses it to set **obase**, which must be between **0** and **DC_BASE_MAX**, inclusive (see the **LIMITS** section and the **NUMBERS** section). If the value on top of the stack has any *scale*, the *scale* is ignored. **k** : Pops the value off of the top of the stack and uses it to set **scale**, which must be non-negative. If the value on top of the stack has any *scale*, the *scale* is ignored. **j** : Pops the value off of the top of the stack and uses it to set **seed**. The meaning of **seed** is dependent on the current pseudo-random number generator but is guaranteed to not change except for new major versions. The *scale* and sign of the value may be significant. If a previously used **seed** value is used again, the pseudo-random number generator is guaranteed to produce the same sequence of pseudo-random numbers as it did when the **seed** value was previously used. The exact value assigned to **seed** is not guaranteed to be returned if the **J** command is used. However, if **seed** *does* return a different value, both values, when assigned to **seed**, are guaranteed to produce the same sequence of pseudo-random numbers. This means that certain values assigned to **seed** will not produce unique sequences of pseudo-random numbers. There is no limit to the length (number of significant decimal digits) or *scale* of the value that can be assigned to **seed**. This is a **non-portable extension**. **I** : Pushes the current value of **ibase** onto the main stack. **O** : Pushes the current value of **obase** onto the main stack. **K** : Pushes the current value of **scale** onto the main stack. **J** : Pushes the current value of **seed** onto the main stack. This is a **non-portable extension**. **T** : Pushes the maximum allowable value of **ibase** onto the main stack. This is a **non-portable extension**. **U** : Pushes the maximum allowable value of **obase** onto the main stack. This is a **non-portable extension**. **V** : Pushes the maximum allowable value of **scale** onto the main stack. This is a **non-portable extension**. **W** : Pushes the maximum (inclusive) integer that can be generated with the **'** pseudo-random number generator command. This is a **non-portable extension**. ## Strings The following commands control strings. dc(1) can work with both numbers and strings, and registers (see the **REGISTERS** section) can hold both strings and numbers. dc(1) always knows whether the contents of a register are a string or a number. While arithmetic operations have to have numbers, and will print an error if given a string, other commands accept strings. Strings can also be executed as macros. For example, if the string **[1pR]** is executed as a macro, then the code **1pR** is executed, meaning that the **1** will be printed with a newline after and then popped from the stack. **\[**_characters_**\]** : Makes a string containing *characters* and pushes it onto the stack. If there are brackets (**\[** and **\]**) in the string, then they must be balanced. Unbalanced brackets can be escaped using a backslash (**\\**) character. If there is a backslash character in the string, the character after it (even another backslash) is put into the string verbatim, but the (first) backslash is not. **a** : The value on top of the stack is popped. If it is a number, it is truncated and its absolute value is taken. The result mod **256** is calculated. If that result is **0**, push an empty string; otherwise, push a one-character string where the character is the result of the mod interpreted as an ASCII character. If it is a string, then a new string is made. If the original string is empty, the new string is empty. If it is not, then the first character of the original string is used to create the new string as a one-character string. The new string is then pushed onto the stack. This is a **non-portable extension**. **x** : Pops a value off of the top of the stack. If it is a number, it is pushed back onto the stack. If it is a string, it is executed as a macro. This behavior is the norm whenever a macro is executed, whether by this command or by the conditional execution commands below. **\>**_r_ : Pops two values off of the stack that must be numbers and compares them. If the first value is greater than the second, then the contents of register *r* are executed. For example, **0 1>a** will execute the contents of register **a**, and **1 0>a** will not. If either or both of the values are not numbers, dc(1) will raise an error and reset (see the **RESET** section). **>**_r_**e**_s_ : Like the above, but will execute register *s* if the comparison fails. If either or both of the values are not numbers, dc(1) will raise an error and reset (see the **RESET** section). This is a **non-portable extension**. **!\>**_r_ : Pops two values off of the stack that must be numbers and compares them. If the first value is not greater than the second (less than or equal to), then the contents of register *r* are executed. If either or both of the values are not numbers, dc(1) will raise an error and reset (see the **RESET** section). **!\>**_r_**e**_s_ : Like the above, but will execute register *s* if the comparison fails. If either or both of the values are not numbers, dc(1) will raise an error and reset (see the **RESET** section). This is a **non-portable extension**. **\<**_r_ : Pops two values off of the stack that must be numbers and compares them. If the first value is less than the second, then the contents of register *r* are executed. If either or both of the values are not numbers, dc(1) will raise an error and reset (see the **RESET** section). **\<**_r_**e**_s_ : Like the above, but will execute register *s* if the comparison fails. If either or both of the values are not numbers, dc(1) will raise an error and reset (see the **RESET** section). This is a **non-portable extension**. **!\<**_r_ : Pops two values off of the stack that must be numbers and compares them. If the first value is not less than the second (greater than or equal to), then the contents of register *r* are executed. If either or both of the values are not numbers, dc(1) will raise an error and reset (see the **RESET** section). **!\<**_r_**e**_s_ : Like the above, but will execute register *s* if the comparison fails. If either or both of the values are not numbers, dc(1) will raise an error and reset (see the **RESET** section). This is a **non-portable extension**. **=**_r_ : Pops two values off of the stack that must be numbers and compares them. If the first value is equal to the second, then the contents of register *r* are executed. If either or both of the values are not numbers, dc(1) will raise an error and reset (see the **RESET** section). **=**_r_**e**_s_ : Like the above, but will execute register *s* if the comparison fails. If either or both of the values are not numbers, dc(1) will raise an error and reset (see the **RESET** section). This is a **non-portable extension**. **!=**_r_ : Pops two values off of the stack that must be numbers and compares them. If the first value is not equal to the second, then the contents of register *r* are executed. If either or both of the values are not numbers, dc(1) will raise an error and reset (see the **RESET** section). **!=**_r_**e**_s_ : Like the above, but will execute register *s* if the comparison fails. If either or both of the values are not numbers, dc(1) will raise an error and reset (see the **RESET** section). This is a **non-portable extension**. **?** : Reads a line from the **stdin** and executes it. This is to allow macros to request input from users. **q** : During execution of a macro, this exits the execution of that macro and the execution of the macro that executed it. If there are no macros, or only one macro executing, dc(1) exits. **Q** : Pops a value from the stack which must be non-negative and is used the number of macro executions to pop off of the execution stack. If the number of levels to pop is greater than the number of executing macros, dc(1) exits. **,** : Pushes the depth of the execution stack onto the stack. The execution stack is the stack of string executions. The number that is pushed onto the stack is exactly as many as is needed to make dc(1) exit with the **Q** command, so the sequence **,Q** will make dc(1) exit. ## Status These commands query status of the stack or its top value. **Z** : Pops a value off of the stack. If it is a number, calculates the number of significant decimal digits it has and pushes the result. It will push **1** if the argument is **0** with no decimal places. If it is a string, pushes the number of characters the string has. **X** : Pops a value off of the stack. If it is a number, pushes the *scale* of the value onto the stack. If it is a string, pushes **0**. **z** : Pushes the current depth of the stack (before execution of this command) onto the stack. **y**_r_ : Pushes the current stack depth of the register *r* onto the main stack. Because each register has a depth of **1** (with the value **0** in the top item) when dc(1) starts, dc(1) requires that each register's stack must always have at least one item; dc(1) will give an error and reset otherwise (see the **RESET** section). This means that this command will never push **0**. This is a **non-portable extension**. ## Arrays These commands manipulate arrays. **:**_r_ : Pops the top two values off of the stack. The second value will be stored in the array *r* (see the **REGISTERS** section), indexed by the first value. **;**_r_ : Pops the value on top of the stack and uses it as an index into the array *r*. The selected value is then pushed onto the stack. **Y**_r_ : Pushes the length of the array *r* onto the stack. This is a **non-portable extension**. ## Global Settings These commands retrieve global settings. These are the only commands that require multiple specific characters, and all of them begin with the letter **g**. Only the characters below are allowed after the character **g**; any other character produces a parse error (see the **ERRORS** section). **gl** : Pushes the line length set by **DC_LINE_LENGTH** (see the **ENVIRONMENT VARIABLES** section) onto the stack. **gz** : Pushes **0** onto the stack if the leading zero setting has not been enabled with the **-z** or **-\-leading-zeroes** options (see the **OPTIONS** section), non-zero otherwise. # REGISTERS Registers are names that can store strings, numbers, and arrays. (Number/string registers do not interfere with array registers.) Each register is also its own stack, so the current register value is the top of the stack for the register. All registers, when first referenced, have one value (**0**) in their stack, and it is a runtime error to attempt to pop that item off of the register stack. In non-extended register mode, a register name is just the single character that follows any command that needs a register name. The only exceptions are: a newline (**'\\n'**) and a left bracket (**'['**); it is a parse error for a newline or a left bracket to be used as a register name. ## Extended Register Mode Unlike most other dc(1) implentations, this dc(1) provides nearly unlimited amounts of registers, if extended register mode is enabled. If extended register mode is enabled (**-x** or **-\-extended-register** command-line arguments are given), then normal single character registers are used *unless* the character immediately following a command that needs a register name is a space (according to **isspace()**) and not a newline (**'\\n'**). In that case, the register name is found according to the regex **\[a-z\]\[a-z0-9\_\]\*** (like bc(1) identifiers), and it is a parse error if the next non-space characters do not match that regex. # RESET When dc(1) encounters an error or a signal that it has a non-default handler for, it resets. This means that several things happen. First, any macros that are executing are stopped and popped off the stack. The behavior is not unlike that of exceptions in programming languages. Then the execution point is set so that any code waiting to execute (after all macros returned) is skipped. Thus, when dc(1) resets, it skips any remaining code waiting to be executed. Then, if it is interactive mode, and the error was not a fatal error (see the **EXIT STATUS** section), it asks for more input; otherwise, it exits with the appropriate return code. # PERFORMANCE Most dc(1) implementations use **char** types to calculate the value of **1** decimal digit at a time, but that can be slow. This dc(1) does something different. It uses large integers to calculate more than **1** decimal digit at a time. If built in a environment where **DC_LONG_BIT** (see the **LIMITS** section) is **64**, then each integer has **9** decimal digits. If built in an environment where **DC_LONG_BIT** is **32** then each integer has **4** decimal digits. This value (the number of decimal digits per large integer) is called **DC_BASE_DIGS**. In addition, this dc(1) uses an even larger integer for overflow checking. This integer type depends on the value of **DC_LONG_BIT**, but is always at least twice as large as the integer type used to store digits. # LIMITS The following are the limits on dc(1): **DC_LONG_BIT** : The number of bits in the **long** type in the environment where dc(1) was built. This determines how many decimal digits can be stored in a single large integer (see the **PERFORMANCE** section). **DC_BASE_DIGS** : The number of decimal digits per large integer (see the **PERFORMANCE** section). Depends on **DC_LONG_BIT**. **DC_BASE_POW** : The max decimal number that each large integer can store (see **DC_BASE_DIGS**) plus **1**. Depends on **DC_BASE_DIGS**. **DC_OVERFLOW_MAX** : The max number that the overflow type (see the **PERFORMANCE** section) can hold. Depends on **DC_LONG_BIT**. **DC_BASE_MAX** : The maximum output base. Set at **DC_BASE_POW**. **DC_DIM_MAX** : The maximum size of arrays. Set at **SIZE_MAX-1**. **DC_SCALE_MAX** : The maximum **scale**. Set at **DC_OVERFLOW_MAX-1**. **DC_STRING_MAX** : The maximum length of strings. Set at **DC_OVERFLOW_MAX-1**. **DC_NAME_MAX** : The maximum length of identifiers. Set at **DC_OVERFLOW_MAX-1**. **DC_NUM_MAX** : The maximum length of a number (in decimal digits), which includes digits after the decimal point. Set at **DC_OVERFLOW_MAX-1**. **DC_RAND_MAX** : The maximum integer (inclusive) returned by the **'** command, if dc(1). Set at **2\^DC_LONG_BIT-1**. Exponent : The maximum allowable exponent (positive or negative). Set at **DC_OVERFLOW_MAX**. Number of vars : The maximum number of vars/arrays. Set at **SIZE_MAX-1**. These limits are meant to be effectively non-existent; the limits are so large (at least on 64-bit machines) that there should not be any point at which they become a problem. In fact, memory should be exhausted before these limits should be hit. # ENVIRONMENT VARIABLES dc(1) recognizes the following environment variables: **DC_ENV_ARGS** : This is another way to give command-line arguments to dc(1). They should be in the same format as all other command-line arguments. These are always processed first, so any files given in **DC_ENV_ARGS** will be processed before arguments and files given on the command-line. This gives the user the ability to set up "standard" options and files to be used at every invocation. The most useful thing for such files to contain would be useful functions that the user might want every time dc(1) runs. Another use would be to use the **-e** option to set **scale** to a value other than **0**. The code that parses **DC_ENV_ARGS** will correctly handle quoted arguments, but it does not understand escape sequences. For example, the string **"/home/gavin/some dc file.dc"** will be correctly parsed, but the string **"/home/gavin/some \"dc\" file.dc"** will include the backslashes. The quote parsing will handle either kind of quotes, **'** or **"**. Thus, if you have a file with any number of single quotes in the name, you can use double quotes as the outside quotes, as in **"some 'dc' file.dc"**, and vice versa if you have a file with double quotes. However, handling a file with both kinds of quotes in **DC_ENV_ARGS** is not supported due to the complexity of the parsing, though such files are still supported on the command-line where the parsing is done by the shell. **DC_LINE_LENGTH** : If this environment variable exists and contains an integer that is greater than **1** and is less than **UINT16_MAX** (**2\^16-1**), dc(1) will output lines to that length, including the backslash newline combo. The default line length is **70**. The special value of **0** will disable line length checking and print numbers without regard to line length and without backslashes and newlines. **DC_SIGINT_RESET** : If dc(1) is not in interactive mode (see the **INTERACTIVE MODE** section), then this environment variable has no effect because dc(1) exits on **SIGINT** when not in interactive mode. However, when dc(1) is in interactive mode, then if this environment variable exists and contains an integer, a non-zero value makes dc(1) reset on **SIGINT**, rather than exit, and zero makes dc(1) exit. If this environment variable exists and is *not* an integer, then dc(1) will exit on **SIGINT**. This environment variable overrides the default, which can be queried with the **-h** or **-\-help** options. **DC_TTY_MODE** : If TTY mode is *not* available (see the **TTY MODE** section), then this environment variable has no effect. However, when TTY mode is available, then if this environment variable exists and contains an integer, then a non-zero value makes dc(1) use TTY mode, and zero makes dc(1) not use TTY mode. This environment variable overrides the default, which can be queried with the **-h** or **-\-help** options. **DC_PROMPT** : If TTY mode is *not* available (see the **TTY MODE** section), then this environment variable has no effect. However, when TTY mode is available, then if this environment variable exists and contains an integer, a non-zero value makes dc(1) use a prompt, and zero or a non-integer makes dc(1) not use a prompt. If this environment variable does not exist and **DC_TTY_MODE** does, then the value of the **DC_TTY_MODE** environment variable is used. This environment variable and the **DC_TTY_MODE** environment variable override the default, which can be queried with the **-h** or **-\-help** options. +**DC_EXPR_EXIT** + +: If any expressions or expression files are given on the command-line with + **-e**, **-\-expression**, **-f**, or **-\-file**, then if this environment + variable exists and contains an integer, a non-zero value makes dc(1) exit + after executing the expressions and expression files, and a non-zero value + makes dc(1) not exit. + + This environment variable overrides the default, which can be queried with + the **-h** or **-\-help** options. + # EXIT STATUS dc(1) returns the following exit statuses: **0** : No error. **1** : A math error occurred. This follows standard practice of using **1** for expected errors, since math errors will happen in the process of normal execution. Math errors include divide by **0**, taking the square root of a negative number, using a negative number as a bound for the pseudo-random number generator, attempting to convert a negative number to a hardware integer, overflow when converting a number to a hardware integer, overflow when calculating the size of a number, and attempting to use a non-integer where an integer is required. Converting to a hardware integer happens for the second operand of the power (**\^**), places (**\@**), left shift (**H**), and right shift (**h**) operators. **2** : A parse error occurred. Parse errors include unexpected **EOF**, using an invalid character, failing to find the end of a string or comment, and using a token where it is invalid. **3** : A runtime error occurred. Runtime errors include assigning an invalid number to any global (**ibase**, **obase**, or **scale**), giving a bad expression to a **read()** call, calling **read()** inside of a **read()** call, type errors (including attempting to execute a number), and attempting an operation when the stack has too few elements. **4** : A fatal error occurred. Fatal errors include memory allocation errors, I/O errors, failing to open files, attempting to use files that do not have only ASCII characters (dc(1) only accepts ASCII characters), attempting to open a directory as a file, and giving invalid command-line options. The exit status **4** is special; when a fatal error occurs, dc(1) always exits and returns **4**, no matter what mode dc(1) is in. The other statuses will only be returned when dc(1) is not in interactive mode (see the **INTERACTIVE MODE** section), since dc(1) resets its state (see the **RESET** section) and accepts more input when one of those errors occurs in interactive mode. This is also the case when interactive mode is forced by the **-i** flag or **-\-interactive** option. These exit statuses allow dc(1) to be used in shell scripting with error checking, and its normal behavior can be forced by using the **-i** flag or **-\-interactive** option. # INTERACTIVE MODE Like bc(1), dc(1) has an interactive mode and a non-interactive mode. Interactive mode is turned on automatically when both **stdin** and **stdout** are hooked to a terminal, but the **-i** flag and **-\-interactive** option can turn it on in other situations. In interactive mode, dc(1) attempts to recover from errors (see the **RESET** section), and in normal execution, flushes **stdout** as soon as execution is done for the current input. dc(1) may also reset on **SIGINT** instead of exit, depending on the contents of, or default for, the **DC_SIGINT_RESET** environment variable (see the **ENVIRONMENT VARIABLES** section). # TTY MODE If **stdin**, **stdout**, and **stderr** are all connected to a TTY, then "TTY mode" is considered to be available, and thus, dc(1) can turn on TTY mode, subject to some settings. If there is the environment variable **DC_TTY_MODE** in the environment (see the **ENVIRONMENT VARIABLES** section), then if that environment variable contains a non-zero integer, dc(1) will turn on TTY mode when **stdin**, **stdout**, and **stderr** are all connected to a TTY. If the **DC_TTY_MODE** environment variable exists but is *not* a non-zero integer, then dc(1) will not turn TTY mode on. If the environment variable **DC_TTY_MODE** does *not* exist, the default setting is used. The default setting can be queried with the **-h** or **-\-help** options. TTY mode is different from interactive mode because interactive mode is required in the [bc(1) specification][1], and interactive mode requires only **stdin** and **stdout** to be connected to a terminal. ## Prompt If TTY mode is available, then a prompt can be enabled. Like TTY mode itself, it can be turned on or off with an environment variable: **DC_PROMPT** (see the **ENVIRONMENT VARIABLES** section). If the environment variable **DC_PROMPT** exists and is a non-zero integer, then the prompt is turned on when **stdin**, **stdout**, and **stderr** are connected to a TTY and the **-P** and **-\-no-prompt** options were not used. The read prompt will be turned on under the same conditions, except that the **-R** and **-\-no-read-prompt** options must also not be used. However, if **DC_PROMPT** does not exist, the prompt can be enabled or disabled with the **DC_TTY_MODE** environment variable, the **-P** and **-\-no-prompt** options, and the **-R** and **-\-no-read-prompt** options. See the **ENVIRONMENT VARIABLES** and **OPTIONS** sections for more details. # SIGNAL HANDLING Sending a **SIGINT** will cause dc(1) to do one of two things. If dc(1) is not in interactive mode (see the **INTERACTIVE MODE** section), or the **DC_SIGINT_RESET** environment variable (see the **ENVIRONMENT VARIABLES** section), or its default, is either not an integer or it is zero, dc(1) will exit. However, if dc(1) is in interactive mode, and the **DC_SIGINT_RESET** or its default is an integer and non-zero, then dc(1) will stop executing the current input and reset (see the **RESET** section) upon receiving a **SIGINT**. Note that "current input" can mean one of two things. If dc(1) is processing input from **stdin** in interactive mode, it will ask for more input. If dc(1) is processing input from a file in interactive mode, it will stop processing the file and start processing the next file, if one exists, or ask for input from **stdin** if no other file exists. This means that if a **SIGINT** is sent to dc(1) as it is executing a file, it can seem as though dc(1) did not respond to the signal since it will immediately start executing the next file. This is by design; most files that users execute when interacting with dc(1) have function definitions, which are quick to parse. If a file takes a long time to execute, there may be a bug in that file. The rest of the files could still be executed without problem, allowing the user to continue. **SIGTERM** and **SIGQUIT** cause dc(1) to clean up and exit, and it uses the default handler for all other signals. # SEE ALSO bc(1) # STANDARDS The dc(1) utility operators are compliant with the operators in the bc(1) [IEEE Std 1003.1-2017 (“POSIX.1-2017”)][1] specification. # BUGS None are known. Report bugs at https://git.yzena.com/gavin/bc. # AUTHOR Gavin D. Howard and contributors. [1]: https://pubs.opengroup.org/onlinepubs/9699919799/utilities/bc.html diff --git a/contrib/bc/manuals/dc/N.1 b/contrib/bc/manuals/dc/N.1 index c5cc36ac9b10..16f89b7ee2a1 100644 --- a/contrib/bc/manuals/dc/N.1 +++ b/contrib/bc/manuals/dc/N.1 @@ -1,1545 +1,1558 @@ .\" .\" SPDX-License-Identifier: BSD-2-Clause .\" .\" Copyright (c) 2018-2021 Gavin D. Howard and contributors. .\" .\" Redistribution and use in source and binary forms, with or without .\" modification, are permitted provided that the following conditions are met: .\" .\" * Redistributions of source code must retain the above copyright notice, .\" this list of conditions and the following disclaimer. .\" .\" * Redistributions in binary form must reproduce the above copyright notice, .\" this list of conditions and the following disclaimer in the documentation .\" and/or other materials provided with the distribution. .\" .\" THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" .\" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE .\" IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE .\" ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE .\" LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR .\" CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF .\" SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS .\" INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN .\" CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) .\" ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE .\" POSSIBILITY OF SUCH DAMAGE. .\" .TH "DC" "1" "June 2021" "Gavin D. Howard" "General Commands Manual" .SH Name .PP dc - arbitrary-precision decimal reverse-Polish notation calculator .SH SYNOPSIS .PP \f[B]dc\f[R] [\f[B]-hiPRvVx\f[R]] [\f[B]--version\f[R]] [\f[B]--help\f[R]] [\f[B]--interactive\f[R]] [\f[B]--no-prompt\f[R]] [\f[B]--no-read-prompt\f[R]] [\f[B]--extended-register\f[R]] [\f[B]-e\f[R] \f[I]expr\f[R]] [\f[B]--expression\f[R]=\f[I]expr\f[R]\&...] [\f[B]-f\f[R] \f[I]file\f[R]\&...] [\f[B]--file\f[R]=\f[I]file\f[R]\&...] [\f[I]file\f[R]\&...] .SH DESCRIPTION .PP dc(1) is an arbitrary-precision calculator. It uses a stack (reverse Polish notation) to store numbers and results of computations. Arithmetic operations pop arguments off of the stack and push the results. .PP If no files are given on the command-line, then dc(1) reads from \f[B]stdin\f[R] (see the \f[B]STDIN\f[R] section). Otherwise, those files are processed, and dc(1) will then exit. .PP If a user wants to set up a standard environment, they can use \f[B]DC_ENV_ARGS\f[R] (see the \f[B]ENVIRONMENT VARIABLES\f[R] section). For example, if a user wants the \f[B]scale\f[R] always set to \f[B]10\f[R], they can set \f[B]DC_ENV_ARGS\f[R] to \f[B]-e 10k\f[R], and this dc(1) will always start with a \f[B]scale\f[R] of \f[B]10\f[R]. .SH OPTIONS .PP The following are the options that dc(1) accepts. .TP \f[B]-h\f[R], \f[B]--help\f[R] Prints a usage message and quits. .TP \f[B]-v\f[R], \f[B]-V\f[R], \f[B]--version\f[R] Print the version information (copyright header) and exit. .TP \f[B]-i\f[R], \f[B]--interactive\f[R] Forces interactive mode. (See the \f[B]INTERACTIVE MODE\f[R] section.) .RS .PP This is a \f[B]non-portable extension\f[R]. .RE .TP \f[B]-L\f[R], \f[B]--no-line-length\f[R] Disables line length checking and prints numbers without backslashes and newlines. In other words, this option sets \f[B]BC_LINE_LENGTH\f[R] to \f[B]0\f[R] (see the \f[B]ENVIRONMENT VARIABLES\f[R] section). .RS .PP This is a \f[B]non-portable extension\f[R]. .RE .TP \f[B]-P\f[R], \f[B]--no-prompt\f[R] Disables the prompt in TTY mode. (The prompt is only enabled in TTY mode. See the \f[B]TTY MODE\f[R] section.) This is mostly for those users that do not want a prompt or are not used to having them in dc(1). Most of those users would want to put this option in \f[B]DC_ENV_ARGS\f[R]. .RS .PP These options override the \f[B]DC_PROMPT\f[R] and \f[B]DC_TTY_MODE\f[R] environment variables (see the \f[B]ENVIRONMENT VARIABLES\f[R] section). .PP This is a \f[B]non-portable extension\f[R]. .RE .TP \f[B]-R\f[R], \f[B]--no-read-prompt\f[R] Disables the read prompt in TTY mode. (The read prompt is only enabled in TTY mode. See the \f[B]TTY MODE\f[R] section.) This is mostly for those users that do not want a read prompt or are not used to having them in dc(1). Most of those users would want to put this option in \f[B]BC_ENV_ARGS\f[R] (see the \f[B]ENVIRONMENT VARIABLES\f[R] section). This option is also useful in hash bang lines of dc(1) scripts that prompt for user input. .RS .PP This option does not disable the regular prompt because the read prompt is only used when the \f[B]?\f[R] command is used. .PP These options \f[I]do\f[R] override the \f[B]DC_PROMPT\f[R] and \f[B]DC_TTY_MODE\f[R] environment variables (see the \f[B]ENVIRONMENT VARIABLES\f[R] section), but only for the read prompt. .PP This is a \f[B]non-portable extension\f[R]. .RE .TP \f[B]-x\f[R] \f[B]--extended-register\f[R] Enables extended register mode. See the \f[I]Extended Register Mode\f[R] subsection of the \f[B]REGISTERS\f[R] section for more information. .RS .PP This is a \f[B]non-portable extension\f[R]. .RE .TP \f[B]-z\f[R], \f[B]--leading-zeroes\f[R] Makes bc(1) print all numbers greater than \f[B]-1\f[R] and less than \f[B]1\f[R], and not equal to \f[B]0\f[R], with a leading zero. .RS .PP This can be set for individual numbers with the \f[B]plz(x)\f[R], plznl(x)**, \f[B]pnlz(x)\f[R], and \f[B]pnlznl(x)\f[R] functions in the extended math library (see the \f[B]LIBRARY\f[R] section). .PP This is a \f[B]non-portable extension\f[R]. .RE .TP \f[B]-e\f[R] \f[I]expr\f[R], \f[B]--expression\f[R]=\f[I]expr\f[R] Evaluates \f[I]expr\f[R]. If multiple expressions are given, they are evaluated in order. If files are given as well (see below), the expressions and files are evaluated in the order given. This means that if a file is given before an expression, the file is read in and evaluated first. .RS .PP If this option is given on the command-line (i.e., not in \f[B]DC_ENV_ARGS\f[R], see the \f[B]ENVIRONMENT VARIABLES\f[R] section), then after processing all expressions and files, dc(1) will exit, unless \f[B]-\f[R] (\f[B]stdin\f[R]) was given as an argument at least once to \f[B]-f\f[R] or \f[B]--file\f[R], whether on the command-line or in \f[B]DC_ENV_ARGS\f[R]. However, if any other \f[B]-e\f[R], \f[B]--expression\f[R], \f[B]-f\f[R], or \f[B]--file\f[R] arguments are given after \f[B]-f-\f[R] or equivalent is given, dc(1) will give a fatal error and exit. .PP This is a \f[B]non-portable extension\f[R]. .RE .TP \f[B]-f\f[R] \f[I]file\f[R], \f[B]--file\f[R]=\f[I]file\f[R] Reads in \f[I]file\f[R] and evaluates it, line by line, as though it were read through \f[B]stdin\f[R]. If expressions are also given (see above), the expressions are evaluated in the order given. .RS .PP If this option is given on the command-line (i.e., not in \f[B]DC_ENV_ARGS\f[R], see the \f[B]ENVIRONMENT VARIABLES\f[R] section), then after processing all expressions and files, dc(1) will exit, unless \f[B]-\f[R] (\f[B]stdin\f[R]) was given as an argument at least once to \f[B]-f\f[R] or \f[B]--file\f[R]. However, if any other \f[B]-e\f[R], \f[B]--expression\f[R], \f[B]-f\f[R], or \f[B]--file\f[R] arguments are given after \f[B]-f-\f[R] or equivalent is given, dc(1) will give a fatal error and exit. .PP This is a \f[B]non-portable extension\f[R]. .RE .PP All long options are \f[B]non-portable extensions\f[R]. .SH STDIN .PP If no files are given on the command-line and no files or expressions are given by the \f[B]-f\f[R], \f[B]--file\f[R], \f[B]-e\f[R], or \f[B]--expression\f[R] options, then dc(1) read from \f[B]stdin\f[R]. .PP However, there is a caveat to this. .PP First, \f[B]stdin\f[R] is evaluated a line at a time. The only exception to this is if a string has been finished, but not ended. This means that, except for escaped brackets, all brackets must be balanced before dc(1) parses and executes. .SH STDOUT .PP Any non-error output is written to \f[B]stdout\f[R]. In addition, if history (see the \f[B]HISTORY\f[R] section) and the prompt (see the \f[B]TTY MODE\f[R] section) are enabled, both are output to \f[B]stdout\f[R]. .PP \f[B]Note\f[R]: Unlike other dc(1) implementations, this dc(1) will issue a fatal error (see the \f[B]EXIT STATUS\f[R] section) if it cannot write to \f[B]stdout\f[R], so if \f[B]stdout\f[R] is closed, as in \f[B]dc >&-\f[R], it will quit with an error. This is done so that dc(1) can report problems when \f[B]stdout\f[R] is redirected to a file. .PP If there are scripts that depend on the behavior of other dc(1) implementations, it is recommended that those scripts be changed to redirect \f[B]stdout\f[R] to \f[B]/dev/null\f[R]. .SH STDERR .PP Any error output is written to \f[B]stderr\f[R]. .PP \f[B]Note\f[R]: Unlike other dc(1) implementations, this dc(1) will issue a fatal error (see the \f[B]EXIT STATUS\f[R] section) if it cannot write to \f[B]stderr\f[R], so if \f[B]stderr\f[R] is closed, as in \f[B]dc 2>&-\f[R], it will quit with an error. This is done so that dc(1) can exit with an error code when \f[B]stderr\f[R] is redirected to a file. .PP If there are scripts that depend on the behavior of other dc(1) implementations, it is recommended that those scripts be changed to redirect \f[B]stderr\f[R] to \f[B]/dev/null\f[R]. .SH SYNTAX .PP Each item in the input source code, either a number (see the \f[B]NUMBERS\f[R] section) or a command (see the \f[B]COMMANDS\f[R] section), is processed and executed, in order. Input is processed immediately when entered. .PP \f[B]ibase\f[R] is a register (see the \f[B]REGISTERS\f[R] section) that determines how to interpret constant numbers. It is the \[lq]input\[rq] base, or the number base used for interpreting input numbers. \f[B]ibase\f[R] is initially \f[B]10\f[R]. The max allowable value for \f[B]ibase\f[R] is \f[B]16\f[R]. The min allowable value for \f[B]ibase\f[R] is \f[B]2\f[R]. The max allowable value for \f[B]ibase\f[R] can be queried in dc(1) programs with the \f[B]T\f[R] command. .PP \f[B]obase\f[R] is a register (see the \f[B]REGISTERS\f[R] section) that determines how to output results. It is the \[lq]output\[rq] base, or the number base used for outputting numbers. \f[B]obase\f[R] is initially \f[B]10\f[R]. The max allowable value for \f[B]obase\f[R] is \f[B]DC_BASE_MAX\f[R] and can be queried with the \f[B]U\f[R] command. The min allowable value for \f[B]obase\f[R] is \f[B]0\f[R]. If \f[B]obase\f[R] is \f[B]0\f[R], values are output in scientific notation, and if \f[B]obase\f[R] is \f[B]1\f[R], values are output in engineering notation. Otherwise, values are output in the specified base. .PP Outputting in scientific and engineering notations are \f[B]non-portable extensions\f[R]. .PP The \f[I]scale\f[R] of an expression is the number of digits in the result of the expression right of the decimal point, and \f[B]scale\f[R] is a register (see the \f[B]REGISTERS\f[R] section) that sets the precision of any operations (with exceptions). \f[B]scale\f[R] is initially \f[B]0\f[R]. \f[B]scale\f[R] cannot be negative. The max allowable value for \f[B]scale\f[R] can be queried in dc(1) programs with the \f[B]V\f[R] command. .PP \f[B]seed\f[R] is a register containing the current seed for the pseudo-random number generator. If the current value of \f[B]seed\f[R] is queried and stored, then if it is assigned to \f[B]seed\f[R] later, the pseudo-random number generator is guaranteed to produce the same sequence of pseudo-random numbers that were generated after the value of \f[B]seed\f[R] was first queried. .PP Multiple values assigned to \f[B]seed\f[R] can produce the same sequence of pseudo-random numbers. Likewise, when a value is assigned to \f[B]seed\f[R], it is not guaranteed that querying \f[B]seed\f[R] immediately after will return the same value. In addition, the value of \f[B]seed\f[R] will change after any call to the \f[B]\[cq]\f[R] command or the \f[B]\[lq]\f[R] command that does not get receive a value of \f[B]0\f[R] or \f[B]1\f[R]. The maximum integer returned by the \f[B]\[cq]\f[R] command can be queried with the \f[B]W\f[R] command. .PP \f[B]Note\f[R]: The values returned by the pseudo-random number generator with the \f[B]\[cq]\f[R] and \f[B]\[lq]\f[R] commands are guaranteed to \f[B]NOT\f[R] be cryptographically secure. This is a consequence of using a seeded pseudo-random number generator. However, they \f[I]are\f[R] guaranteed to be reproducible with identical \f[B]seed\f[R] values. This means that the pseudo-random values from dc(1) should only be used where a reproducible stream of pseudo-random numbers is \f[I]ESSENTIAL\f[R]. In any other case, use a non-seeded pseudo-random number generator. .PP The pseudo-random number generator, \f[B]seed\f[R], and all associated operations are \f[B]non-portable extensions\f[R]. .SS Comments .PP Comments go from \f[B]#\f[R] until, and not including, the next newline. This is a \f[B]non-portable extension\f[R]. .SH NUMBERS .PP Numbers are strings made up of digits, uppercase letters up to \f[B]F\f[R], and at most \f[B]1\f[R] period for a radix. Numbers can have up to \f[B]DC_NUM_MAX\f[R] digits. Uppercase letters are equal to \f[B]9\f[R] + their position in the alphabet (i.e., \f[B]A\f[R] equals \f[B]10\f[R], or \f[B]9+1\f[R]). If a digit or letter makes no sense with the current value of \f[B]ibase\f[R], they are set to the value of the highest valid digit in \f[B]ibase\f[R]. .PP Single-character numbers (i.e., \f[B]A\f[R] alone) take the value that they would have if they were valid digits, regardless of the value of \f[B]ibase\f[R]. This means that \f[B]A\f[R] alone always equals decimal \f[B]10\f[R] and \f[B]F\f[R] alone always equals decimal \f[B]15\f[R]. .PP In addition, dc(1) accepts numbers in scientific notation. These have the form \f[B]e\f[R]. The exponent (the portion after the \f[B]e\f[R]) must be an integer. An example is \f[B]1.89237e9\f[R], which is equal to \f[B]1892370000\f[R]. Negative exponents are also allowed, so \f[B]4.2890e_3\f[R] is equal to \f[B]0.0042890\f[R]. .PP \f[B]WARNING\f[R]: Both the number and the exponent in scientific notation are interpreted according to the current \f[B]ibase\f[R], but the number is still multiplied by \f[B]10\[ha]exponent\f[R] regardless of the current \f[B]ibase\f[R]. For example, if \f[B]ibase\f[R] is \f[B]16\f[R] and dc(1) is given the number string \f[B]FFeA\f[R], the resulting decimal number will be \f[B]2550000000000\f[R], and if dc(1) is given the number string \f[B]10e_4\f[R], the resulting decimal number will be \f[B]0.0016\f[R]. .PP Accepting input as scientific notation is a \f[B]non-portable extension\f[R]. .SH COMMANDS .PP The valid commands are listed below. .SS Printing .PP These commands are used for printing. .PP Note that both scientific notation and engineering notation are available for printing numbers. Scientific notation is activated by assigning \f[B]0\f[R] to \f[B]obase\f[R] using \f[B]0o\f[R], and engineering notation is activated by assigning \f[B]1\f[R] to \f[B]obase\f[R] using \f[B]1o\f[R]. To deactivate them, just assign a different value to \f[B]obase\f[R]. .PP Printing numbers in scientific notation and/or engineering notation is a \f[B]non-portable extension\f[R]. .TP \f[B]p\f[R] Prints the value on top of the stack, whether number or string, and prints a newline after. .RS .PP This does not alter the stack. .RE .TP \f[B]n\f[R] Prints the value on top of the stack, whether number or string, and pops it off of the stack. .TP \f[B]P\f[R] Pops a value off the stack. .RS .PP If the value is a number, it is truncated and the absolute value of the result is printed as though \f[B]obase\f[R] is \f[B]256\f[R] and each digit is interpreted as an 8-bit ASCII character, making it a byte stream. .PP If the value is a string, it is printed without a trailing newline. .PP This is a \f[B]non-portable extension\f[R]. .RE .TP \f[B]f\f[R] Prints the entire contents of the stack, in order from newest to oldest, without altering anything. .RS .PP Users should use this command when they get lost. .RE .SS Arithmetic .PP These are the commands used for arithmetic. .TP \f[B]+\f[R] The top two values are popped off the stack, added, and the result is pushed onto the stack. The \f[I]scale\f[R] of the result is equal to the max \f[I]scale\f[R] of both operands. .TP \f[B]-\f[R] The top two values are popped off the stack, subtracted, and the result is pushed onto the stack. The \f[I]scale\f[R] of the result is equal to the max \f[I]scale\f[R] of both operands. .TP \f[B]*\f[R] The top two values are popped off the stack, multiplied, and the result is pushed onto the stack. If \f[B]a\f[R] is the \f[I]scale\f[R] of the first expression and \f[B]b\f[R] is the \f[I]scale\f[R] of the second expression, the \f[I]scale\f[R] of the result is equal to \f[B]min(a+b,max(scale,a,b))\f[R] where \f[B]min()\f[R] and \f[B]max()\f[R] return the obvious values. .TP \f[B]/\f[R] The top two values are popped off the stack, divided, and the result is pushed onto the stack. The \f[I]scale\f[R] of the result is equal to \f[B]scale\f[R]. .RS .PP The first value popped off of the stack must be non-zero. .RE .TP \f[B]%\f[R] The top two values are popped off the stack, remaindered, and the result is pushed onto the stack. .RS .PP Remaindering is equivalent to 1) Computing \f[B]a/b\f[R] to current \f[B]scale\f[R], and 2) Using the result of step 1 to calculate \f[B]a-(a/b)*b\f[R] to \f[I]scale\f[R] \f[B]max(scale+scale(b),scale(a))\f[R]. .PP The first value popped off of the stack must be non-zero. .RE .TP \f[B]\[ti]\f[R] The top two values are popped off the stack, divided and remaindered, and the results (divided first, remainder second) are pushed onto the stack. This is equivalent to \f[B]x y / x y %\f[R] except that \f[B]x\f[R] and \f[B]y\f[R] are only evaluated once. .RS .PP The first value popped off of the stack must be non-zero. .PP This is a \f[B]non-portable extension\f[R]. .RE .TP \f[B]\[ha]\f[R] The top two values are popped off the stack, the second is raised to the power of the first, and the result is pushed onto the stack. The \f[I]scale\f[R] of the result is equal to \f[B]scale\f[R]. .RS .PP The first value popped off of the stack must be an integer, and if that value is negative, the second value popped off of the stack must be non-zero. .RE .TP \f[B]v\f[R] The top value is popped off the stack, its square root is computed, and the result is pushed onto the stack. The \f[I]scale\f[R] of the result is equal to \f[B]scale\f[R]. .RS .PP The value popped off of the stack must be non-negative. .RE .TP \f[B]_\f[R] If this command \f[I]immediately\f[R] precedes a number (i.e., no spaces or other commands), then that number is input as a negative number. .RS .PP Otherwise, the top value on the stack is popped and copied, and the copy is negated and pushed onto the stack. This behavior without a number is a \f[B]non-portable extension\f[R]. .RE .TP \f[B]b\f[R] The top value is popped off the stack, and if it is zero, it is pushed back onto the stack. Otherwise, its absolute value is pushed onto the stack. .RS .PP This is a \f[B]non-portable extension\f[R]. .RE .TP \f[B]|\f[R] The top three values are popped off the stack, a modular exponentiation is computed, and the result is pushed onto the stack. .RS .PP The first value popped is used as the reduction modulus and must be an integer and non-zero. The second value popped is used as the exponent and must be an integer and non-negative. The third value popped is the base and must be an integer. .PP This is a \f[B]non-portable extension\f[R]. .RE .TP \f[B]$\f[R] The top value is popped off the stack and copied, and the copy is truncated and pushed onto the stack. .RS .PP This is a \f[B]non-portable extension\f[R]. .RE .TP \f[B]\[at]\f[R] The top two values are popped off the stack, and the precision of the second is set to the value of the first, whether by truncation or extension. .RS .PP The first value popped off of the stack must be an integer and non-negative. .PP This is a \f[B]non-portable extension\f[R]. .RE .TP \f[B]H\f[R] The top two values are popped off the stack, and the second is shifted left (radix shifted right) to the value of the first. .RS .PP The first value popped off of the stack must be an integer and non-negative. .PP This is a \f[B]non-portable extension\f[R]. .RE .TP \f[B]h\f[R] The top two values are popped off the stack, and the second is shifted right (radix shifted left) to the value of the first. .RS .PP The first value popped off of the stack must be an integer and non-negative. .PP This is a \f[B]non-portable extension\f[R]. .RE .TP \f[B]G\f[R] The top two values are popped off of the stack, they are compared, and a \f[B]1\f[R] is pushed if they are equal, or \f[B]0\f[R] otherwise. .RS .PP This is a \f[B]non-portable extension\f[R]. .RE .TP \f[B]N\f[R] The top value is popped off of the stack, and if it a \f[B]0\f[R], a \f[B]1\f[R] is pushed; otherwise, a \f[B]0\f[R] is pushed. .RS .PP This is a \f[B]non-portable extension\f[R]. .RE .TP \f[B](\f[R] The top two values are popped off of the stack, they are compared, and a \f[B]1\f[R] is pushed if the first is less than the second, or \f[B]0\f[R] otherwise. .RS .PP This is a \f[B]non-portable extension\f[R]. .RE .TP \f[B]{\f[R] The top two values are popped off of the stack, they are compared, and a \f[B]1\f[R] is pushed if the first is less than or equal to the second, or \f[B]0\f[R] otherwise. .RS .PP This is a \f[B]non-portable extension\f[R]. .RE .TP \f[B])\f[R] The top two values are popped off of the stack, they are compared, and a \f[B]1\f[R] is pushed if the first is greater than the second, or \f[B]0\f[R] otherwise. .RS .PP This is a \f[B]non-portable extension\f[R]. .RE .TP \f[B]}\f[R] The top two values are popped off of the stack, they are compared, and a \f[B]1\f[R] is pushed if the first is greater than or equal to the second, or \f[B]0\f[R] otherwise. .RS .PP This is a \f[B]non-portable extension\f[R]. .RE .TP \f[B]M\f[R] The top two values are popped off of the stack. If they are both non-zero, a \f[B]1\f[R] is pushed onto the stack. If either of them is zero, or both of them are, then a \f[B]0\f[R] is pushed onto the stack. .RS .PP This is like the \f[B]&&\f[R] operator in bc(1), and it is \f[I]not\f[R] a short-circuit operator. .PP This is a \f[B]non-portable extension\f[R]. .RE .TP \f[B]m\f[R] The top two values are popped off of the stack. If at least one of them is non-zero, a \f[B]1\f[R] is pushed onto the stack. If both of them are zero, then a \f[B]0\f[R] is pushed onto the stack. .RS .PP This is like the \f[B]||\f[R] operator in bc(1), and it is \f[I]not\f[R] a short-circuit operator. .PP This is a \f[B]non-portable extension\f[R]. .RE .SS Pseudo-Random Number Generator .PP dc(1) has a built-in pseudo-random number generator. These commands query the pseudo-random number generator. (See Parameters for more information about the \f[B]seed\f[R] value that controls the pseudo-random number generator.) .PP The pseudo-random number generator is guaranteed to \f[B]NOT\f[R] be cryptographically secure. .TP \f[B]\[cq]\f[R] Generates an integer between 0 and \f[B]DC_RAND_MAX\f[R], inclusive (see the \f[B]LIMITS\f[R] section). .RS .PP The generated integer is made as unbiased as possible, subject to the limitations of the pseudo-random number generator. .PP This is a \f[B]non-portable extension\f[R]. .RE .TP \f[B]\[lq]\f[R] Pops a value off of the stack, which is used as an \f[B]exclusive\f[R] upper bound on the integer that will be generated. If the bound is negative or is a non-integer, an error is raised, and dc(1) resets (see the \f[B]RESET\f[R] section) while \f[B]seed\f[R] remains unchanged. If the bound is larger than \f[B]DC_RAND_MAX\f[R], the higher bound is honored by generating several pseudo-random integers, multiplying them by appropriate powers of \f[B]DC_RAND_MAX+1\f[R], and adding them together. Thus, the size of integer that can be generated with this command is unbounded. Using this command will change the value of \f[B]seed\f[R], unless the operand is \f[B]0\f[R] or \f[B]1\f[R]. In that case, \f[B]0\f[R] is pushed onto the stack, and \f[B]seed\f[R] is \f[I]not\f[R] changed. .RS .PP The generated integer is made as unbiased as possible, subject to the limitations of the pseudo-random number generator. .PP This is a \f[B]non-portable extension\f[R]. .RE .SS Stack Control .PP These commands control the stack. .TP \f[B]c\f[R] Removes all items from (\[lq]clears\[rq]) the stack. .TP \f[B]d\f[R] Copies the item on top of the stack (\[lq]duplicates\[rq]) and pushes the copy onto the stack. .TP \f[B]r\f[R] Swaps (\[lq]reverses\[rq]) the two top items on the stack. .TP \f[B]R\f[R] Pops (\[lq]removes\[rq]) the top value from the stack. .SS Register Control .PP These commands control registers (see the \f[B]REGISTERS\f[R] section). .TP \f[B]s\f[R]\f[I]r\f[R] Pops the value off the top of the stack and stores it into register \f[I]r\f[R]. .TP \f[B]l\f[R]\f[I]r\f[R] Copies the value in register \f[I]r\f[R] and pushes it onto the stack. This does not alter the contents of \f[I]r\f[R]. .TP \f[B]S\f[R]\f[I]r\f[R] Pops the value off the top of the (main) stack and pushes it onto the stack of register \f[I]r\f[R]. The previous value of the register becomes inaccessible. .TP \f[B]L\f[R]\f[I]r\f[R] Pops the value off the top of the stack for register \f[I]r\f[R] and push it onto the main stack. The previous value in the stack for register \f[I]r\f[R], if any, is now accessible via the \f[B]l\f[R]\f[I]r\f[R] command. .SS Parameters .PP These commands control the values of \f[B]ibase\f[R], \f[B]obase\f[R], \f[B]scale\f[R], and \f[B]seed\f[R]. Also see the \f[B]SYNTAX\f[R] section. .TP \f[B]i\f[R] Pops the value off of the top of the stack and uses it to set \f[B]ibase\f[R], which must be between \f[B]2\f[R] and \f[B]16\f[R], inclusive. .RS .PP If the value on top of the stack has any \f[I]scale\f[R], the \f[I]scale\f[R] is ignored. .RE .TP \f[B]o\f[R] Pops the value off of the top of the stack and uses it to set \f[B]obase\f[R], which must be between \f[B]0\f[R] and \f[B]DC_BASE_MAX\f[R], inclusive (see the \f[B]LIMITS\f[R] section and the \f[B]NUMBERS\f[R] section). .RS .PP If the value on top of the stack has any \f[I]scale\f[R], the \f[I]scale\f[R] is ignored. .RE .TP \f[B]k\f[R] Pops the value off of the top of the stack and uses it to set \f[B]scale\f[R], which must be non-negative. .RS .PP If the value on top of the stack has any \f[I]scale\f[R], the \f[I]scale\f[R] is ignored. .RE .TP \f[B]j\f[R] Pops the value off of the top of the stack and uses it to set \f[B]seed\f[R]. The meaning of \f[B]seed\f[R] is dependent on the current pseudo-random number generator but is guaranteed to not change except for new major versions. .RS .PP The \f[I]scale\f[R] and sign of the value may be significant. .PP If a previously used \f[B]seed\f[R] value is used again, the pseudo-random number generator is guaranteed to produce the same sequence of pseudo-random numbers as it did when the \f[B]seed\f[R] value was previously used. .PP The exact value assigned to \f[B]seed\f[R] is not guaranteed to be returned if the \f[B]J\f[R] command is used. However, if \f[B]seed\f[R] \f[I]does\f[R] return a different value, both values, when assigned to \f[B]seed\f[R], are guaranteed to produce the same sequence of pseudo-random numbers. This means that certain values assigned to \f[B]seed\f[R] will not produce unique sequences of pseudo-random numbers. .PP There is no limit to the length (number of significant decimal digits) or \f[I]scale\f[R] of the value that can be assigned to \f[B]seed\f[R]. .PP This is a \f[B]non-portable extension\f[R]. .RE .TP \f[B]I\f[R] Pushes the current value of \f[B]ibase\f[R] onto the main stack. .TP \f[B]O\f[R] Pushes the current value of \f[B]obase\f[R] onto the main stack. .TP \f[B]K\f[R] Pushes the current value of \f[B]scale\f[R] onto the main stack. .TP \f[B]J\f[R] Pushes the current value of \f[B]seed\f[R] onto the main stack. .RS .PP This is a \f[B]non-portable extension\f[R]. .RE .TP \f[B]T\f[R] Pushes the maximum allowable value of \f[B]ibase\f[R] onto the main stack. .RS .PP This is a \f[B]non-portable extension\f[R]. .RE .TP \f[B]U\f[R] Pushes the maximum allowable value of \f[B]obase\f[R] onto the main stack. .RS .PP This is a \f[B]non-portable extension\f[R]. .RE .TP \f[B]V\f[R] Pushes the maximum allowable value of \f[B]scale\f[R] onto the main stack. .RS .PP This is a \f[B]non-portable extension\f[R]. .RE .TP \f[B]W\f[R] Pushes the maximum (inclusive) integer that can be generated with the \f[B]\[cq]\f[R] pseudo-random number generator command. .RS .PP This is a \f[B]non-portable extension\f[R]. .RE .SS Strings .PP The following commands control strings. .PP dc(1) can work with both numbers and strings, and registers (see the \f[B]REGISTERS\f[R] section) can hold both strings and numbers. dc(1) always knows whether the contents of a register are a string or a number. .PP While arithmetic operations have to have numbers, and will print an error if given a string, other commands accept strings. .PP Strings can also be executed as macros. For example, if the string \f[B][1pR]\f[R] is executed as a macro, then the code \f[B]1pR\f[R] is executed, meaning that the \f[B]1\f[R] will be printed with a newline after and then popped from the stack. .TP \f[B][\f[R]\f[I]characters\f[R]\f[B]]\f[R] Makes a string containing \f[I]characters\f[R] and pushes it onto the stack. .RS .PP If there are brackets (\f[B][\f[R] and \f[B]]\f[R]) in the string, then they must be balanced. Unbalanced brackets can be escaped using a backslash (\f[B]\[rs]\f[R]) character. .PP If there is a backslash character in the string, the character after it (even another backslash) is put into the string verbatim, but the (first) backslash is not. .RE .TP \f[B]a\f[R] The value on top of the stack is popped. .RS .PP If it is a number, it is truncated and its absolute value is taken. The result mod \f[B]256\f[R] is calculated. If that result is \f[B]0\f[R], push an empty string; otherwise, push a one-character string where the character is the result of the mod interpreted as an ASCII character. .PP If it is a string, then a new string is made. If the original string is empty, the new string is empty. If it is not, then the first character of the original string is used to create the new string as a one-character string. The new string is then pushed onto the stack. .PP This is a \f[B]non-portable extension\f[R]. .RE .TP \f[B]x\f[R] Pops a value off of the top of the stack. .RS .PP If it is a number, it is pushed back onto the stack. .PP If it is a string, it is executed as a macro. .PP This behavior is the norm whenever a macro is executed, whether by this command or by the conditional execution commands below. .RE .TP \f[B]>\f[R]\f[I]r\f[R] Pops two values off of the stack that must be numbers and compares them. If the first value is greater than the second, then the contents of register \f[I]r\f[R] are executed. .RS .PP For example, \f[B]0 1>a\f[R] will execute the contents of register \f[B]a\f[R], and \f[B]1 0>a\f[R] will not. .PP If either or both of the values are not numbers, dc(1) will raise an error and reset (see the \f[B]RESET\f[R] section). .RE .TP \f[B]>\f[R]\f[I]r\f[R]\f[B]e\f[R]\f[I]s\f[R] Like the above, but will execute register \f[I]s\f[R] if the comparison fails. .RS .PP If either or both of the values are not numbers, dc(1) will raise an error and reset (see the \f[B]RESET\f[R] section). .PP This is a \f[B]non-portable extension\f[R]. .RE .TP \f[B]!>\f[R]\f[I]r\f[R] Pops two values off of the stack that must be numbers and compares them. If the first value is not greater than the second (less than or equal to), then the contents of register \f[I]r\f[R] are executed. .RS .PP If either or both of the values are not numbers, dc(1) will raise an error and reset (see the \f[B]RESET\f[R] section). .RE .TP \f[B]!>\f[R]\f[I]r\f[R]\f[B]e\f[R]\f[I]s\f[R] Like the above, but will execute register \f[I]s\f[R] if the comparison fails. .RS .PP If either or both of the values are not numbers, dc(1) will raise an error and reset (see the \f[B]RESET\f[R] section). .PP This is a \f[B]non-portable extension\f[R]. .RE .TP \f[B]<\f[R]\f[I]r\f[R] Pops two values off of the stack that must be numbers and compares them. If the first value is less than the second, then the contents of register \f[I]r\f[R] are executed. .RS .PP If either or both of the values are not numbers, dc(1) will raise an error and reset (see the \f[B]RESET\f[R] section). .RE .TP \f[B]<\f[R]\f[I]r\f[R]\f[B]e\f[R]\f[I]s\f[R] Like the above, but will execute register \f[I]s\f[R] if the comparison fails. .RS .PP If either or both of the values are not numbers, dc(1) will raise an error and reset (see the \f[B]RESET\f[R] section). .PP This is a \f[B]non-portable extension\f[R]. .RE .TP \f[B]!<\f[R]\f[I]r\f[R] Pops two values off of the stack that must be numbers and compares them. If the first value is not less than the second (greater than or equal to), then the contents of register \f[I]r\f[R] are executed. .RS .PP If either or both of the values are not numbers, dc(1) will raise an error and reset (see the \f[B]RESET\f[R] section). .RE .TP \f[B]!<\f[R]\f[I]r\f[R]\f[B]e\f[R]\f[I]s\f[R] Like the above, but will execute register \f[I]s\f[R] if the comparison fails. .RS .PP If either or both of the values are not numbers, dc(1) will raise an error and reset (see the \f[B]RESET\f[R] section). .PP This is a \f[B]non-portable extension\f[R]. .RE .TP \f[B]=\f[R]\f[I]r\f[R] Pops two values off of the stack that must be numbers and compares them. If the first value is equal to the second, then the contents of register \f[I]r\f[R] are executed. .RS .PP If either or both of the values are not numbers, dc(1) will raise an error and reset (see the \f[B]RESET\f[R] section). .RE .TP \f[B]=\f[R]\f[I]r\f[R]\f[B]e\f[R]\f[I]s\f[R] Like the above, but will execute register \f[I]s\f[R] if the comparison fails. .RS .PP If either or both of the values are not numbers, dc(1) will raise an error and reset (see the \f[B]RESET\f[R] section). .PP This is a \f[B]non-portable extension\f[R]. .RE .TP \f[B]!=\f[R]\f[I]r\f[R] Pops two values off of the stack that must be numbers and compares them. If the first value is not equal to the second, then the contents of register \f[I]r\f[R] are executed. .RS .PP If either or both of the values are not numbers, dc(1) will raise an error and reset (see the \f[B]RESET\f[R] section). .RE .TP \f[B]!=\f[R]\f[I]r\f[R]\f[B]e\f[R]\f[I]s\f[R] Like the above, but will execute register \f[I]s\f[R] if the comparison fails. .RS .PP If either or both of the values are not numbers, dc(1) will raise an error and reset (see the \f[B]RESET\f[R] section). .PP This is a \f[B]non-portable extension\f[R]. .RE .TP \f[B]?\f[R] Reads a line from the \f[B]stdin\f[R] and executes it. This is to allow macros to request input from users. .TP \f[B]q\f[R] During execution of a macro, this exits the execution of that macro and the execution of the macro that executed it. If there are no macros, or only one macro executing, dc(1) exits. .TP \f[B]Q\f[R] Pops a value from the stack which must be non-negative and is used the number of macro executions to pop off of the execution stack. If the number of levels to pop is greater than the number of executing macros, dc(1) exits. .TP \f[B],\f[R] Pushes the depth of the execution stack onto the stack. The execution stack is the stack of string executions. The number that is pushed onto the stack is exactly as many as is needed to make dc(1) exit with the \f[B]Q\f[R] command, so the sequence \f[B],Q\f[R] will make dc(1) exit. .SS Status .PP These commands query status of the stack or its top value. .TP \f[B]Z\f[R] Pops a value off of the stack. .RS .PP If it is a number, calculates the number of significant decimal digits it has and pushes the result. It will push \f[B]1\f[R] if the argument is \f[B]0\f[R] with no decimal places. .PP If it is a string, pushes the number of characters the string has. .RE .TP \f[B]X\f[R] Pops a value off of the stack. .RS .PP If it is a number, pushes the \f[I]scale\f[R] of the value onto the stack. .PP If it is a string, pushes \f[B]0\f[R]. .RE .TP \f[B]z\f[R] Pushes the current depth of the stack (before execution of this command) onto the stack. .TP \f[B]y\f[R]\f[I]r\f[R] Pushes the current stack depth of the register \f[I]r\f[R] onto the main stack. .RS .PP Because each register has a depth of \f[B]1\f[R] (with the value \f[B]0\f[R] in the top item) when dc(1) starts, dc(1) requires that each register\[cq]s stack must always have at least one item; dc(1) will give an error and reset otherwise (see the \f[B]RESET\f[R] section). This means that this command will never push \f[B]0\f[R]. .PP This is a \f[B]non-portable extension\f[R]. .RE .SS Arrays .PP These commands manipulate arrays. .TP \f[B]:\f[R]\f[I]r\f[R] Pops the top two values off of the stack. The second value will be stored in the array \f[I]r\f[R] (see the \f[B]REGISTERS\f[R] section), indexed by the first value. .TP \f[B];\f[R]\f[I]r\f[R] Pops the value on top of the stack and uses it as an index into the array \f[I]r\f[R]. The selected value is then pushed onto the stack. .TP \f[B]Y\f[R]\f[I]r\f[R] Pushes the length of the array \f[I]r\f[R] onto the stack. .RS .PP This is a \f[B]non-portable extension\f[R]. .RE .SS Global Settings .PP These commands retrieve global settings. These are the only commands that require multiple specific characters, and all of them begin with the letter \f[B]g\f[R]. Only the characters below are allowed after the character \f[B]g\f[R]; any other character produces a parse error (see the \f[B]ERRORS\f[R] section). .TP \f[B]gl\f[R] Pushes the line length set by \f[B]DC_LINE_LENGTH\f[R] (see the \f[B]ENVIRONMENT VARIABLES\f[R] section) onto the stack. .TP \f[B]gz\f[R] Pushes \f[B]0\f[R] onto the stack if the leading zero setting has not been enabled with the \f[B]-z\f[R] or \f[B]--leading-zeroes\f[R] options (see the \f[B]OPTIONS\f[R] section), non-zero otherwise. .SH REGISTERS .PP Registers are names that can store strings, numbers, and arrays. (Number/string registers do not interfere with array registers.) .PP Each register is also its own stack, so the current register value is the top of the stack for the register. All registers, when first referenced, have one value (\f[B]0\f[R]) in their stack, and it is a runtime error to attempt to pop that item off of the register stack. .PP In non-extended register mode, a register name is just the single character that follows any command that needs a register name. The only exceptions are: a newline (\f[B]`\[rs]n'\f[R]) and a left bracket (\f[B]`['\f[R]); it is a parse error for a newline or a left bracket to be used as a register name. .SS Extended Register Mode .PP Unlike most other dc(1) implentations, this dc(1) provides nearly unlimited amounts of registers, if extended register mode is enabled. .PP If extended register mode is enabled (\f[B]-x\f[R] or \f[B]--extended-register\f[R] command-line arguments are given), then normal single character registers are used \f[I]unless\f[R] the character immediately following a command that needs a register name is a space (according to \f[B]isspace()\f[R]) and not a newline (\f[B]`\[rs]n'\f[R]). .PP In that case, the register name is found according to the regex \f[B][a-z][a-z0-9_]*\f[R] (like bc(1) identifiers), and it is a parse error if the next non-space characters do not match that regex. .SH RESET .PP When dc(1) encounters an error or a signal that it has a non-default handler for, it resets. This means that several things happen. .PP First, any macros that are executing are stopped and popped off the stack. The behavior is not unlike that of exceptions in programming languages. Then the execution point is set so that any code waiting to execute (after all macros returned) is skipped. .PP Thus, when dc(1) resets, it skips any remaining code waiting to be executed. Then, if it is interactive mode, and the error was not a fatal error (see the \f[B]EXIT STATUS\f[R] section), it asks for more input; otherwise, it exits with the appropriate return code. .SH PERFORMANCE .PP Most dc(1) implementations use \f[B]char\f[R] types to calculate the value of \f[B]1\f[R] decimal digit at a time, but that can be slow. This dc(1) does something different. .PP It uses large integers to calculate more than \f[B]1\f[R] decimal digit at a time. If built in a environment where \f[B]DC_LONG_BIT\f[R] (see the \f[B]LIMITS\f[R] section) is \f[B]64\f[R], then each integer has \f[B]9\f[R] decimal digits. If built in an environment where \f[B]DC_LONG_BIT\f[R] is \f[B]32\f[R] then each integer has \f[B]4\f[R] decimal digits. This value (the number of decimal digits per large integer) is called \f[B]DC_BASE_DIGS\f[R]. .PP In addition, this dc(1) uses an even larger integer for overflow checking. This integer type depends on the value of \f[B]DC_LONG_BIT\f[R], but is always at least twice as large as the integer type used to store digits. .SH LIMITS .PP The following are the limits on dc(1): .TP \f[B]DC_LONG_BIT\f[R] The number of bits in the \f[B]long\f[R] type in the environment where dc(1) was built. This determines how many decimal digits can be stored in a single large integer (see the \f[B]PERFORMANCE\f[R] section). .TP \f[B]DC_BASE_DIGS\f[R] The number of decimal digits per large integer (see the \f[B]PERFORMANCE\f[R] section). Depends on \f[B]DC_LONG_BIT\f[R]. .TP \f[B]DC_BASE_POW\f[R] The max decimal number that each large integer can store (see \f[B]DC_BASE_DIGS\f[R]) plus \f[B]1\f[R]. Depends on \f[B]DC_BASE_DIGS\f[R]. .TP \f[B]DC_OVERFLOW_MAX\f[R] The max number that the overflow type (see the \f[B]PERFORMANCE\f[R] section) can hold. Depends on \f[B]DC_LONG_BIT\f[R]. .TP \f[B]DC_BASE_MAX\f[R] The maximum output base. Set at \f[B]DC_BASE_POW\f[R]. .TP \f[B]DC_DIM_MAX\f[R] The maximum size of arrays. Set at \f[B]SIZE_MAX-1\f[R]. .TP \f[B]DC_SCALE_MAX\f[R] The maximum \f[B]scale\f[R]. Set at \f[B]DC_OVERFLOW_MAX-1\f[R]. .TP \f[B]DC_STRING_MAX\f[R] The maximum length of strings. Set at \f[B]DC_OVERFLOW_MAX-1\f[R]. .TP \f[B]DC_NAME_MAX\f[R] The maximum length of identifiers. Set at \f[B]DC_OVERFLOW_MAX-1\f[R]. .TP \f[B]DC_NUM_MAX\f[R] The maximum length of a number (in decimal digits), which includes digits after the decimal point. Set at \f[B]DC_OVERFLOW_MAX-1\f[R]. .TP \f[B]DC_RAND_MAX\f[R] The maximum integer (inclusive) returned by the \f[B]\[cq]\f[R] command, if dc(1). Set at \f[B]2\[ha]DC_LONG_BIT-1\f[R]. .TP Exponent The maximum allowable exponent (positive or negative). Set at \f[B]DC_OVERFLOW_MAX\f[R]. .TP Number of vars The maximum number of vars/arrays. Set at \f[B]SIZE_MAX-1\f[R]. .PP These limits are meant to be effectively non-existent; the limits are so large (at least on 64-bit machines) that there should not be any point at which they become a problem. In fact, memory should be exhausted before these limits should be hit. .SH ENVIRONMENT VARIABLES .PP dc(1) recognizes the following environment variables: .TP \f[B]DC_ENV_ARGS\f[R] This is another way to give command-line arguments to dc(1). They should be in the same format as all other command-line arguments. These are always processed first, so any files given in \f[B]DC_ENV_ARGS\f[R] will be processed before arguments and files given on the command-line. This gives the user the ability to set up \[lq]standard\[rq] options and files to be used at every invocation. The most useful thing for such files to contain would be useful functions that the user might want every time dc(1) runs. Another use would be to use the \f[B]-e\f[R] option to set \f[B]scale\f[R] to a value other than \f[B]0\f[R]. .RS .PP The code that parses \f[B]DC_ENV_ARGS\f[R] will correctly handle quoted arguments, but it does not understand escape sequences. For example, the string \f[B]\[lq]/home/gavin/some dc file.dc\[rq]\f[R] will be correctly parsed, but the string \f[B]\[lq]/home/gavin/some \[dq]dc\[dq] file.dc\[rq]\f[R] will include the backslashes. .PP The quote parsing will handle either kind of quotes, \f[B]\[cq]\f[R] or \f[B]\[lq]\f[R]. Thus, if you have a file with any number of single quotes in the name, you can use double quotes as the outside quotes, as in \f[B]\[lq]some `dc' file.dc\[rq]\f[R], and vice versa if you have a file with double quotes. However, handling a file with both kinds of quotes in \f[B]DC_ENV_ARGS\f[R] is not supported due to the complexity of the parsing, though such files are still supported on the command-line where the parsing is done by the shell. .RE .TP \f[B]DC_LINE_LENGTH\f[R] If this environment variable exists and contains an integer that is greater than \f[B]1\f[R] and is less than \f[B]UINT16_MAX\f[R] (\f[B]2\[ha]16-1\f[R]), dc(1) will output lines to that length, including the backslash newline combo. The default line length is \f[B]70\f[R]. .RS .PP The special value of \f[B]0\f[R] will disable line length checking and print numbers without regard to line length and without backslashes and newlines. .RE .TP \f[B]DC_SIGINT_RESET\f[R] If dc(1) is not in interactive mode (see the \f[B]INTERACTIVE MODE\f[R] section), then this environment variable has no effect because dc(1) exits on \f[B]SIGINT\f[R] when not in interactive mode. .RS .PP However, when dc(1) is in interactive mode, then if this environment variable exists and contains an integer, a non-zero value makes dc(1) reset on \f[B]SIGINT\f[R], rather than exit, and zero makes dc(1) exit. If this environment variable exists and is \f[I]not\f[R] an integer, then dc(1) will exit on \f[B]SIGINT\f[R]. .PP This environment variable overrides the default, which can be queried with the \f[B]-h\f[R] or \f[B]--help\f[R] options. .RE .TP \f[B]DC_TTY_MODE\f[R] If TTY mode is \f[I]not\f[R] available (see the \f[B]TTY MODE\f[R] section), then this environment variable has no effect. .RS .PP However, when TTY mode is available, then if this environment variable exists and contains an integer, then a non-zero value makes dc(1) use TTY mode, and zero makes dc(1) not use TTY mode. .PP This environment variable overrides the default, which can be queried with the \f[B]-h\f[R] or \f[B]--help\f[R] options. .RE .TP \f[B]DC_PROMPT\f[R] If TTY mode is \f[I]not\f[R] available (see the \f[B]TTY MODE\f[R] section), then this environment variable has no effect. .RS .PP However, when TTY mode is available, then if this environment variable exists and contains an integer, a non-zero value makes dc(1) use a prompt, and zero or a non-integer makes dc(1) not use a prompt. If this environment variable does not exist and \f[B]DC_TTY_MODE\f[R] does, then the value of the \f[B]DC_TTY_MODE\f[R] environment variable is used. .PP This environment variable and the \f[B]DC_TTY_MODE\f[R] environment variable override the default, which can be queried with the \f[B]-h\f[R] or \f[B]--help\f[R] options. .RE +.TP +\f[B]DC_EXPR_EXIT\f[R] +If any expressions or expression files are given on the command-line +with \f[B]-e\f[R], \f[B]--expression\f[R], \f[B]-f\f[R], or +\f[B]--file\f[R], then if this environment variable exists and contains +an integer, a non-zero value makes dc(1) exit after executing the +expressions and expression files, and a non-zero value makes dc(1) not +exit. +.RS +.PP +This environment variable overrides the default, which can be queried +with the \f[B]-h\f[R] or \f[B]--help\f[R] options. +.RE .SH EXIT STATUS .PP dc(1) returns the following exit statuses: .TP \f[B]0\f[R] No error. .TP \f[B]1\f[R] A math error occurred. This follows standard practice of using \f[B]1\f[R] for expected errors, since math errors will happen in the process of normal execution. .RS .PP Math errors include divide by \f[B]0\f[R], taking the square root of a negative number, using a negative number as a bound for the pseudo-random number generator, attempting to convert a negative number to a hardware integer, overflow when converting a number to a hardware integer, overflow when calculating the size of a number, and attempting to use a non-integer where an integer is required. .PP Converting to a hardware integer happens for the second operand of the power (\f[B]\[ha]\f[R]), places (\f[B]\[at]\f[R]), left shift (\f[B]H\f[R]), and right shift (\f[B]h\f[R]) operators. .RE .TP \f[B]2\f[R] A parse error occurred. .RS .PP Parse errors include unexpected \f[B]EOF\f[R], using an invalid character, failing to find the end of a string or comment, and using a token where it is invalid. .RE .TP \f[B]3\f[R] A runtime error occurred. .RS .PP Runtime errors include assigning an invalid number to any global (\f[B]ibase\f[R], \f[B]obase\f[R], or \f[B]scale\f[R]), giving a bad expression to a \f[B]read()\f[R] call, calling \f[B]read()\f[R] inside of a \f[B]read()\f[R] call, type errors (including attempting to execute a number), and attempting an operation when the stack has too few elements. .RE .TP \f[B]4\f[R] A fatal error occurred. .RS .PP Fatal errors include memory allocation errors, I/O errors, failing to open files, attempting to use files that do not have only ASCII characters (dc(1) only accepts ASCII characters), attempting to open a directory as a file, and giving invalid command-line options. .RE .PP The exit status \f[B]4\f[R] is special; when a fatal error occurs, dc(1) always exits and returns \f[B]4\f[R], no matter what mode dc(1) is in. .PP The other statuses will only be returned when dc(1) is not in interactive mode (see the \f[B]INTERACTIVE MODE\f[R] section), since dc(1) resets its state (see the \f[B]RESET\f[R] section) and accepts more input when one of those errors occurs in interactive mode. This is also the case when interactive mode is forced by the \f[B]-i\f[R] flag or \f[B]--interactive\f[R] option. .PP These exit statuses allow dc(1) to be used in shell scripting with error checking, and its normal behavior can be forced by using the \f[B]-i\f[R] flag or \f[B]--interactive\f[R] option. .SH INTERACTIVE MODE .PP Like bc(1), dc(1) has an interactive mode and a non-interactive mode. Interactive mode is turned on automatically when both \f[B]stdin\f[R] and \f[B]stdout\f[R] are hooked to a terminal, but the \f[B]-i\f[R] flag and \f[B]--interactive\f[R] option can turn it on in other situations. .PP In interactive mode, dc(1) attempts to recover from errors (see the \f[B]RESET\f[R] section), and in normal execution, flushes \f[B]stdout\f[R] as soon as execution is done for the current input. dc(1) may also reset on \f[B]SIGINT\f[R] instead of exit, depending on the contents of, or default for, the \f[B]DC_SIGINT_RESET\f[R] environment variable (see the \f[B]ENVIRONMENT VARIABLES\f[R] section). .SH TTY MODE .PP If \f[B]stdin\f[R], \f[B]stdout\f[R], and \f[B]stderr\f[R] are all connected to a TTY, then \[lq]TTY mode\[rq] is considered to be available, and thus, dc(1) can turn on TTY mode, subject to some settings. .PP If there is the environment variable \f[B]DC_TTY_MODE\f[R] in the environment (see the \f[B]ENVIRONMENT VARIABLES\f[R] section), then if that environment variable contains a non-zero integer, dc(1) will turn on TTY mode when \f[B]stdin\f[R], \f[B]stdout\f[R], and \f[B]stderr\f[R] are all connected to a TTY. If the \f[B]DC_TTY_MODE\f[R] environment variable exists but is \f[I]not\f[R] a non-zero integer, then dc(1) will not turn TTY mode on. .PP If the environment variable \f[B]DC_TTY_MODE\f[R] does \f[I]not\f[R] exist, the default setting is used. The default setting can be queried with the \f[B]-h\f[R] or \f[B]--help\f[R] options. .PP TTY mode is different from interactive mode because interactive mode is required in the bc(1) specification (https://pubs.opengroup.org/onlinepubs/9699919799/utilities/bc.html), and interactive mode requires only \f[B]stdin\f[R] and \f[B]stdout\f[R] to be connected to a terminal. .SS Command-Line History .PP Command-line history is only enabled if TTY mode is, i.e., that \f[B]stdin\f[R], \f[B]stdout\f[R], and \f[B]stderr\f[R] are connected to a TTY and the \f[B]DC_TTY_MODE\f[R] environment variable (see the \f[B]ENVIRONMENT VARIABLES\f[R] section) and its default do not disable TTY mode. See the \f[B]COMMAND LINE HISTORY\f[R] section for more information. .SS Prompt .PP If TTY mode is available, then a prompt can be enabled. Like TTY mode itself, it can be turned on or off with an environment variable: \f[B]DC_PROMPT\f[R] (see the \f[B]ENVIRONMENT VARIABLES\f[R] section). .PP If the environment variable \f[B]DC_PROMPT\f[R] exists and is a non-zero integer, then the prompt is turned on when \f[B]stdin\f[R], \f[B]stdout\f[R], and \f[B]stderr\f[R] are connected to a TTY and the \f[B]-P\f[R] and \f[B]--no-prompt\f[R] options were not used. The read prompt will be turned on under the same conditions, except that the \f[B]-R\f[R] and \f[B]--no-read-prompt\f[R] options must also not be used. .PP However, if \f[B]DC_PROMPT\f[R] does not exist, the prompt can be enabled or disabled with the \f[B]DC_TTY_MODE\f[R] environment variable, the \f[B]-P\f[R] and \f[B]--no-prompt\f[R] options, and the \f[B]-R\f[R] and \f[B]--no-read-prompt\f[R] options. See the \f[B]ENVIRONMENT VARIABLES\f[R] and \f[B]OPTIONS\f[R] sections for more details. .SH SIGNAL HANDLING .PP Sending a \f[B]SIGINT\f[R] will cause dc(1) to do one of two things. .PP If dc(1) is not in interactive mode (see the \f[B]INTERACTIVE MODE\f[R] section), or the \f[B]DC_SIGINT_RESET\f[R] environment variable (see the \f[B]ENVIRONMENT VARIABLES\f[R] section), or its default, is either not an integer or it is zero, dc(1) will exit. .PP However, if dc(1) is in interactive mode, and the \f[B]DC_SIGINT_RESET\f[R] or its default is an integer and non-zero, then dc(1) will stop executing the current input and reset (see the \f[B]RESET\f[R] section) upon receiving a \f[B]SIGINT\f[R]. .PP Note that \[lq]current input\[rq] can mean one of two things. If dc(1) is processing input from \f[B]stdin\f[R] in interactive mode, it will ask for more input. If dc(1) is processing input from a file in interactive mode, it will stop processing the file and start processing the next file, if one exists, or ask for input from \f[B]stdin\f[R] if no other file exists. .PP This means that if a \f[B]SIGINT\f[R] is sent to dc(1) as it is executing a file, it can seem as though dc(1) did not respond to the signal since it will immediately start executing the next file. This is by design; most files that users execute when interacting with dc(1) have function definitions, which are quick to parse. If a file takes a long time to execute, there may be a bug in that file. The rest of the files could still be executed without problem, allowing the user to continue. .PP \f[B]SIGTERM\f[R] and \f[B]SIGQUIT\f[R] cause dc(1) to clean up and exit, and it uses the default handler for all other signals. The one exception is \f[B]SIGHUP\f[R]; in that case, and only when dc(1) is in TTY mode (see the \f[B]TTY MODE\f[R] section), a \f[B]SIGHUP\f[R] will cause dc(1) to clean up and exit. .SH COMMAND LINE HISTORY .PP dc(1) supports interactive command-line editing. .PP If dc(1) can be in TTY mode (see the \f[B]TTY MODE\f[R] section), history can be enabled. This means that command-line history can only be enabled when \f[B]stdin\f[R], \f[B]stdout\f[R], and \f[B]stderr\f[R] are all connected to a TTY. .PP Like TTY mode itself, it can be turned on or off with the environment variable \f[B]DC_TTY_MODE\f[R] (see the \f[B]ENVIRONMENT VARIABLES\f[R] section). .PP \f[B]Note\f[R]: tabs are converted to 8 spaces. .SH SEE ALSO .PP bc(1) .SH STANDARDS .PP The dc(1) utility operators are compliant with the operators in the bc(1) IEEE Std 1003.1-2017 (\[lq]POSIX.1-2017\[rq]) (https://pubs.opengroup.org/onlinepubs/9699919799/utilities/bc.html) specification. .SH BUGS .PP None are known. Report bugs at https://git.yzena.com/gavin/bc. .SH AUTHOR .PP Gavin D. Howard and contributors. diff --git a/contrib/bc/manuals/dc/N.1.md b/contrib/bc/manuals/dc/N.1.md index fea23028e483..a14c922b4dbc 100644 --- a/contrib/bc/manuals/dc/N.1.md +++ b/contrib/bc/manuals/dc/N.1.md @@ -1,1379 +1,1390 @@ # Name dc - arbitrary-precision decimal reverse-Polish notation calculator # SYNOPSIS **dc** [**-hiPRvVx**] [**-\-version**] [**-\-help**] [**-\-interactive**] [**-\-no-prompt**] [**-\-no-read-prompt**] [**-\-extended-register**] [**-e** *expr*] [**-\-expression**=*expr*...] [**-f** *file*...] [**-\-file**=*file*...] [*file*...] # DESCRIPTION dc(1) is an arbitrary-precision calculator. It uses a stack (reverse Polish notation) to store numbers and results of computations. Arithmetic operations pop arguments off of the stack and push the results. If no files are given on the command-line, then dc(1) reads from **stdin** (see the **STDIN** section). Otherwise, those files are processed, and dc(1) will then exit. If a user wants to set up a standard environment, they can use **DC_ENV_ARGS** (see the **ENVIRONMENT VARIABLES** section). For example, if a user wants the **scale** always set to **10**, they can set **DC_ENV_ARGS** to **-e 10k**, and this dc(1) will always start with a **scale** of **10**. # OPTIONS The following are the options that dc(1) accepts. **-h**, **-\-help** : Prints a usage message and quits. **-v**, **-V**, **-\-version** : Print the version information (copyright header) and exit. **-i**, **-\-interactive** : Forces interactive mode. (See the **INTERACTIVE MODE** section.) This is a **non-portable extension**. **-L**, **-\-no-line-length** : Disables line length checking and prints numbers without backslashes and newlines. In other words, this option sets **BC_LINE_LENGTH** to **0** (see the **ENVIRONMENT VARIABLES** section). This is a **non-portable extension**. **-P**, **-\-no-prompt** : Disables the prompt in TTY mode. (The prompt is only enabled in TTY mode. See the **TTY MODE** section.) This is mostly for those users that do not want a prompt or are not used to having them in dc(1). Most of those users would want to put this option in **DC_ENV_ARGS**. These options override the **DC_PROMPT** and **DC_TTY_MODE** environment variables (see the **ENVIRONMENT VARIABLES** section). This is a **non-portable extension**. **-R**, **-\-no-read-prompt** : Disables the read prompt in TTY mode. (The read prompt is only enabled in TTY mode. See the **TTY MODE** section.) This is mostly for those users that do not want a read prompt or are not used to having them in dc(1). Most of those users would want to put this option in **BC_ENV_ARGS** (see the **ENVIRONMENT VARIABLES** section). This option is also useful in hash bang lines of dc(1) scripts that prompt for user input. This option does not disable the regular prompt because the read prompt is only used when the **?** command is used. These options *do* override the **DC_PROMPT** and **DC_TTY_MODE** environment variables (see the **ENVIRONMENT VARIABLES** section), but only for the read prompt. This is a **non-portable extension**. **-x** **-\-extended-register** : Enables extended register mode. See the *Extended Register Mode* subsection of the **REGISTERS** section for more information. This is a **non-portable extension**. **-z**, **-\-leading-zeroes** : Makes bc(1) print all numbers greater than **-1** and less than **1**, and not equal to **0**, with a leading zero. This can be set for individual numbers with the **plz(x)**, plznl(x)**, **pnlz(x)**, and **pnlznl(x)** functions in the extended math library (see the **LIBRARY** section). This is a **non-portable extension**. **-e** *expr*, **-\-expression**=*expr* : Evaluates *expr*. If multiple expressions are given, they are evaluated in order. If files are given as well (see below), the expressions and files are evaluated in the order given. This means that if a file is given before an expression, the file is read in and evaluated first. If this option is given on the command-line (i.e., not in **DC_ENV_ARGS**, see the **ENVIRONMENT VARIABLES** section), then after processing all expressions and files, dc(1) will exit, unless **-** (**stdin**) was given as an argument at least once to **-f** or **-\-file**, whether on the command-line or in **DC_ENV_ARGS**. However, if any other **-e**, **-\-expression**, **-f**, or **-\-file** arguments are given after **-f-** or equivalent is given, dc(1) will give a fatal error and exit. This is a **non-portable extension**. **-f** *file*, **-\-file**=*file* : Reads in *file* and evaluates it, line by line, as though it were read through **stdin**. If expressions are also given (see above), the expressions are evaluated in the order given. If this option is given on the command-line (i.e., not in **DC_ENV_ARGS**, see the **ENVIRONMENT VARIABLES** section), then after processing all expressions and files, dc(1) will exit, unless **-** (**stdin**) was given as an argument at least once to **-f** or **-\-file**. However, if any other **-e**, **-\-expression**, **-f**, or **-\-file** arguments are given after **-f-** or equivalent is given, dc(1) will give a fatal error and exit. This is a **non-portable extension**. All long options are **non-portable extensions**. # STDIN If no files are given on the command-line and no files or expressions are given by the **-f**, **-\-file**, **-e**, or **-\-expression** options, then dc(1) read from **stdin**. However, there is a caveat to this. First, **stdin** is evaluated a line at a time. The only exception to this is if a string has been finished, but not ended. This means that, except for escaped brackets, all brackets must be balanced before dc(1) parses and executes. # STDOUT Any non-error output is written to **stdout**. In addition, if history (see the **HISTORY** section) and the prompt (see the **TTY MODE** section) are enabled, both are output to **stdout**. **Note**: Unlike other dc(1) implementations, this dc(1) will issue a fatal error (see the **EXIT STATUS** section) if it cannot write to **stdout**, so if **stdout** is closed, as in **dc >&-**, it will quit with an error. This is done so that dc(1) can report problems when **stdout** is redirected to a file. If there are scripts that depend on the behavior of other dc(1) implementations, it is recommended that those scripts be changed to redirect **stdout** to **/dev/null**. # STDERR Any error output is written to **stderr**. **Note**: Unlike other dc(1) implementations, this dc(1) will issue a fatal error (see the **EXIT STATUS** section) if it cannot write to **stderr**, so if **stderr** is closed, as in **dc 2>&-**, it will quit with an error. This is done so that dc(1) can exit with an error code when **stderr** is redirected to a file. If there are scripts that depend on the behavior of other dc(1) implementations, it is recommended that those scripts be changed to redirect **stderr** to **/dev/null**. # SYNTAX Each item in the input source code, either a number (see the **NUMBERS** section) or a command (see the **COMMANDS** section), is processed and executed, in order. Input is processed immediately when entered. **ibase** is a register (see the **REGISTERS** section) that determines how to interpret constant numbers. It is the "input" base, or the number base used for interpreting input numbers. **ibase** is initially **10**. The max allowable value for **ibase** is **16**. The min allowable value for **ibase** is **2**. The max allowable value for **ibase** can be queried in dc(1) programs with the **T** command. **obase** is a register (see the **REGISTERS** section) that determines how to output results. It is the "output" base, or the number base used for outputting numbers. **obase** is initially **10**. The max allowable value for **obase** is **DC_BASE_MAX** and can be queried with the **U** command. The min allowable value for **obase** is **0**. If **obase** is **0**, values are output in scientific notation, and if **obase** is **1**, values are output in engineering notation. Otherwise, values are output in the specified base. Outputting in scientific and engineering notations are **non-portable extensions**. The *scale* of an expression is the number of digits in the result of the expression right of the decimal point, and **scale** is a register (see the **REGISTERS** section) that sets the precision of any operations (with exceptions). **scale** is initially **0**. **scale** cannot be negative. The max allowable value for **scale** can be queried in dc(1) programs with the **V** command. **seed** is a register containing the current seed for the pseudo-random number generator. If the current value of **seed** is queried and stored, then if it is assigned to **seed** later, the pseudo-random number generator is guaranteed to produce the same sequence of pseudo-random numbers that were generated after the value of **seed** was first queried. Multiple values assigned to **seed** can produce the same sequence of pseudo-random numbers. Likewise, when a value is assigned to **seed**, it is not guaranteed that querying **seed** immediately after will return the same value. In addition, the value of **seed** will change after any call to the **'** command or the **"** command that does not get receive a value of **0** or **1**. The maximum integer returned by the **'** command can be queried with the **W** command. **Note**: The values returned by the pseudo-random number generator with the **'** and **"** commands are guaranteed to **NOT** be cryptographically secure. This is a consequence of using a seeded pseudo-random number generator. However, they *are* guaranteed to be reproducible with identical **seed** values. This means that the pseudo-random values from dc(1) should only be used where a reproducible stream of pseudo-random numbers is *ESSENTIAL*. In any other case, use a non-seeded pseudo-random number generator. The pseudo-random number generator, **seed**, and all associated operations are **non-portable extensions**. ## Comments Comments go from **#** until, and not including, the next newline. This is a **non-portable extension**. # NUMBERS Numbers are strings made up of digits, uppercase letters up to **F**, and at most **1** period for a radix. Numbers can have up to **DC_NUM_MAX** digits. Uppercase letters are equal to **9** + their position in the alphabet (i.e., **A** equals **10**, or **9+1**). If a digit or letter makes no sense with the current value of **ibase**, they are set to the value of the highest valid digit in **ibase**. Single-character numbers (i.e., **A** alone) take the value that they would have if they were valid digits, regardless of the value of **ibase**. This means that **A** alone always equals decimal **10** and **F** alone always equals decimal **15**. In addition, dc(1) accepts numbers in scientific notation. These have the form **\e\**. The exponent (the portion after the **e**) must be an integer. An example is **1.89237e9**, which is equal to **1892370000**. Negative exponents are also allowed, so **4.2890e_3** is equal to **0.0042890**. **WARNING**: Both the number and the exponent in scientific notation are interpreted according to the current **ibase**, but the number is still multiplied by **10\^exponent** regardless of the current **ibase**. For example, if **ibase** is **16** and dc(1) is given the number string **FFeA**, the resulting decimal number will be **2550000000000**, and if dc(1) is given the number string **10e_4**, the resulting decimal number will be **0.0016**. Accepting input as scientific notation is a **non-portable extension**. # COMMANDS The valid commands are listed below. ## Printing These commands are used for printing. Note that both scientific notation and engineering notation are available for printing numbers. Scientific notation is activated by assigning **0** to **obase** using **0o**, and engineering notation is activated by assigning **1** to **obase** using **1o**. To deactivate them, just assign a different value to **obase**. Printing numbers in scientific notation and/or engineering notation is a **non-portable extension**. **p** : Prints the value on top of the stack, whether number or string, and prints a newline after. This does not alter the stack. **n** : Prints the value on top of the stack, whether number or string, and pops it off of the stack. **P** : Pops a value off the stack. If the value is a number, it is truncated and the absolute value of the result is printed as though **obase** is **256** and each digit is interpreted as an 8-bit ASCII character, making it a byte stream. If the value is a string, it is printed without a trailing newline. This is a **non-portable extension**. **f** : Prints the entire contents of the stack, in order from newest to oldest, without altering anything. Users should use this command when they get lost. ## Arithmetic These are the commands used for arithmetic. **+** : The top two values are popped off the stack, added, and the result is pushed onto the stack. The *scale* of the result is equal to the max *scale* of both operands. **-** : The top two values are popped off the stack, subtracted, and the result is pushed onto the stack. The *scale* of the result is equal to the max *scale* of both operands. **\*** : The top two values are popped off the stack, multiplied, and the result is pushed onto the stack. If **a** is the *scale* of the first expression and **b** is the *scale* of the second expression, the *scale* of the result is equal to **min(a+b,max(scale,a,b))** where **min()** and **max()** return the obvious values. **/** : The top two values are popped off the stack, divided, and the result is pushed onto the stack. The *scale* of the result is equal to **scale**. The first value popped off of the stack must be non-zero. **%** : The top two values are popped off the stack, remaindered, and the result is pushed onto the stack. Remaindering is equivalent to 1) Computing **a/b** to current **scale**, and 2) Using the result of step 1 to calculate **a-(a/b)\*b** to *scale* **max(scale+scale(b),scale(a))**. The first value popped off of the stack must be non-zero. **~** : The top two values are popped off the stack, divided and remaindered, and the results (divided first, remainder second) are pushed onto the stack. This is equivalent to **x y / x y %** except that **x** and **y** are only evaluated once. The first value popped off of the stack must be non-zero. This is a **non-portable extension**. **\^** : The top two values are popped off the stack, the second is raised to the power of the first, and the result is pushed onto the stack. The *scale* of the result is equal to **scale**. The first value popped off of the stack must be an integer, and if that value is negative, the second value popped off of the stack must be non-zero. **v** : The top value is popped off the stack, its square root is computed, and the result is pushed onto the stack. The *scale* of the result is equal to **scale**. The value popped off of the stack must be non-negative. **\_** : If this command *immediately* precedes a number (i.e., no spaces or other commands), then that number is input as a negative number. Otherwise, the top value on the stack is popped and copied, and the copy is negated and pushed onto the stack. This behavior without a number is a **non-portable extension**. **b** : The top value is popped off the stack, and if it is zero, it is pushed back onto the stack. Otherwise, its absolute value is pushed onto the stack. This is a **non-portable extension**. **|** : The top three values are popped off the stack, a modular exponentiation is computed, and the result is pushed onto the stack. The first value popped is used as the reduction modulus and must be an integer and non-zero. The second value popped is used as the exponent and must be an integer and non-negative. The third value popped is the base and must be an integer. This is a **non-portable extension**. **\$** : The top value is popped off the stack and copied, and the copy is truncated and pushed onto the stack. This is a **non-portable extension**. **\@** : The top two values are popped off the stack, and the precision of the second is set to the value of the first, whether by truncation or extension. The first value popped off of the stack must be an integer and non-negative. This is a **non-portable extension**. **H** : The top two values are popped off the stack, and the second is shifted left (radix shifted right) to the value of the first. The first value popped off of the stack must be an integer and non-negative. This is a **non-portable extension**. **h** : The top two values are popped off the stack, and the second is shifted right (radix shifted left) to the value of the first. The first value popped off of the stack must be an integer and non-negative. This is a **non-portable extension**. **G** : The top two values are popped off of the stack, they are compared, and a **1** is pushed if they are equal, or **0** otherwise. This is a **non-portable extension**. **N** : The top value is popped off of the stack, and if it a **0**, a **1** is pushed; otherwise, a **0** is pushed. This is a **non-portable extension**. **(** : The top two values are popped off of the stack, they are compared, and a **1** is pushed if the first is less than the second, or **0** otherwise. This is a **non-portable extension**. **{** : The top two values are popped off of the stack, they are compared, and a **1** is pushed if the first is less than or equal to the second, or **0** otherwise. This is a **non-portable extension**. **)** : The top two values are popped off of the stack, they are compared, and a **1** is pushed if the first is greater than the second, or **0** otherwise. This is a **non-portable extension**. **}** : The top two values are popped off of the stack, they are compared, and a **1** is pushed if the first is greater than or equal to the second, or **0** otherwise. This is a **non-portable extension**. **M** : The top two values are popped off of the stack. If they are both non-zero, a **1** is pushed onto the stack. If either of them is zero, or both of them are, then a **0** is pushed onto the stack. This is like the **&&** operator in bc(1), and it is *not* a short-circuit operator. This is a **non-portable extension**. **m** : The top two values are popped off of the stack. If at least one of them is non-zero, a **1** is pushed onto the stack. If both of them are zero, then a **0** is pushed onto the stack. This is like the **||** operator in bc(1), and it is *not* a short-circuit operator. This is a **non-portable extension**. ## Pseudo-Random Number Generator dc(1) has a built-in pseudo-random number generator. These commands query the pseudo-random number generator. (See Parameters for more information about the **seed** value that controls the pseudo-random number generator.) The pseudo-random number generator is guaranteed to **NOT** be cryptographically secure. **'** : Generates an integer between 0 and **DC_RAND_MAX**, inclusive (see the **LIMITS** section). The generated integer is made as unbiased as possible, subject to the limitations of the pseudo-random number generator. This is a **non-portable extension**. **"** : Pops a value off of the stack, which is used as an **exclusive** upper bound on the integer that will be generated. If the bound is negative or is a non-integer, an error is raised, and dc(1) resets (see the **RESET** section) while **seed** remains unchanged. If the bound is larger than **DC_RAND_MAX**, the higher bound is honored by generating several pseudo-random integers, multiplying them by appropriate powers of **DC_RAND_MAX+1**, and adding them together. Thus, the size of integer that can be generated with this command is unbounded. Using this command will change the value of **seed**, unless the operand is **0** or **1**. In that case, **0** is pushed onto the stack, and **seed** is *not* changed. The generated integer is made as unbiased as possible, subject to the limitations of the pseudo-random number generator. This is a **non-portable extension**. ## Stack Control These commands control the stack. **c** : Removes all items from ("clears") the stack. **d** : Copies the item on top of the stack ("duplicates") and pushes the copy onto the stack. **r** : Swaps ("reverses") the two top items on the stack. **R** : Pops ("removes") the top value from the stack. ## Register Control These commands control registers (see the **REGISTERS** section). **s**_r_ : Pops the value off the top of the stack and stores it into register *r*. **l**_r_ : Copies the value in register *r* and pushes it onto the stack. This does not alter the contents of *r*. **S**_r_ : Pops the value off the top of the (main) stack and pushes it onto the stack of register *r*. The previous value of the register becomes inaccessible. **L**_r_ : Pops the value off the top of the stack for register *r* and push it onto the main stack. The previous value in the stack for register *r*, if any, is now accessible via the **l**_r_ command. ## Parameters These commands control the values of **ibase**, **obase**, **scale**, and **seed**. Also see the **SYNTAX** section. **i** : Pops the value off of the top of the stack and uses it to set **ibase**, which must be between **2** and **16**, inclusive. If the value on top of the stack has any *scale*, the *scale* is ignored. **o** : Pops the value off of the top of the stack and uses it to set **obase**, which must be between **0** and **DC_BASE_MAX**, inclusive (see the **LIMITS** section and the **NUMBERS** section). If the value on top of the stack has any *scale*, the *scale* is ignored. **k** : Pops the value off of the top of the stack and uses it to set **scale**, which must be non-negative. If the value on top of the stack has any *scale*, the *scale* is ignored. **j** : Pops the value off of the top of the stack and uses it to set **seed**. The meaning of **seed** is dependent on the current pseudo-random number generator but is guaranteed to not change except for new major versions. The *scale* and sign of the value may be significant. If a previously used **seed** value is used again, the pseudo-random number generator is guaranteed to produce the same sequence of pseudo-random numbers as it did when the **seed** value was previously used. The exact value assigned to **seed** is not guaranteed to be returned if the **J** command is used. However, if **seed** *does* return a different value, both values, when assigned to **seed**, are guaranteed to produce the same sequence of pseudo-random numbers. This means that certain values assigned to **seed** will not produce unique sequences of pseudo-random numbers. There is no limit to the length (number of significant decimal digits) or *scale* of the value that can be assigned to **seed**. This is a **non-portable extension**. **I** : Pushes the current value of **ibase** onto the main stack. **O** : Pushes the current value of **obase** onto the main stack. **K** : Pushes the current value of **scale** onto the main stack. **J** : Pushes the current value of **seed** onto the main stack. This is a **non-portable extension**. **T** : Pushes the maximum allowable value of **ibase** onto the main stack. This is a **non-portable extension**. **U** : Pushes the maximum allowable value of **obase** onto the main stack. This is a **non-portable extension**. **V** : Pushes the maximum allowable value of **scale** onto the main stack. This is a **non-portable extension**. **W** : Pushes the maximum (inclusive) integer that can be generated with the **'** pseudo-random number generator command. This is a **non-portable extension**. ## Strings The following commands control strings. dc(1) can work with both numbers and strings, and registers (see the **REGISTERS** section) can hold both strings and numbers. dc(1) always knows whether the contents of a register are a string or a number. While arithmetic operations have to have numbers, and will print an error if given a string, other commands accept strings. Strings can also be executed as macros. For example, if the string **[1pR]** is executed as a macro, then the code **1pR** is executed, meaning that the **1** will be printed with a newline after and then popped from the stack. **\[**_characters_**\]** : Makes a string containing *characters* and pushes it onto the stack. If there are brackets (**\[** and **\]**) in the string, then they must be balanced. Unbalanced brackets can be escaped using a backslash (**\\**) character. If there is a backslash character in the string, the character after it (even another backslash) is put into the string verbatim, but the (first) backslash is not. **a** : The value on top of the stack is popped. If it is a number, it is truncated and its absolute value is taken. The result mod **256** is calculated. If that result is **0**, push an empty string; otherwise, push a one-character string where the character is the result of the mod interpreted as an ASCII character. If it is a string, then a new string is made. If the original string is empty, the new string is empty. If it is not, then the first character of the original string is used to create the new string as a one-character string. The new string is then pushed onto the stack. This is a **non-portable extension**. **x** : Pops a value off of the top of the stack. If it is a number, it is pushed back onto the stack. If it is a string, it is executed as a macro. This behavior is the norm whenever a macro is executed, whether by this command or by the conditional execution commands below. **\>**_r_ : Pops two values off of the stack that must be numbers and compares them. If the first value is greater than the second, then the contents of register *r* are executed. For example, **0 1>a** will execute the contents of register **a**, and **1 0>a** will not. If either or both of the values are not numbers, dc(1) will raise an error and reset (see the **RESET** section). **>**_r_**e**_s_ : Like the above, but will execute register *s* if the comparison fails. If either or both of the values are not numbers, dc(1) will raise an error and reset (see the **RESET** section). This is a **non-portable extension**. **!\>**_r_ : Pops two values off of the stack that must be numbers and compares them. If the first value is not greater than the second (less than or equal to), then the contents of register *r* are executed. If either or both of the values are not numbers, dc(1) will raise an error and reset (see the **RESET** section). **!\>**_r_**e**_s_ : Like the above, but will execute register *s* if the comparison fails. If either or both of the values are not numbers, dc(1) will raise an error and reset (see the **RESET** section). This is a **non-portable extension**. **\<**_r_ : Pops two values off of the stack that must be numbers and compares them. If the first value is less than the second, then the contents of register *r* are executed. If either or both of the values are not numbers, dc(1) will raise an error and reset (see the **RESET** section). **\<**_r_**e**_s_ : Like the above, but will execute register *s* if the comparison fails. If either or both of the values are not numbers, dc(1) will raise an error and reset (see the **RESET** section). This is a **non-portable extension**. **!\<**_r_ : Pops two values off of the stack that must be numbers and compares them. If the first value is not less than the second (greater than or equal to), then the contents of register *r* are executed. If either or both of the values are not numbers, dc(1) will raise an error and reset (see the **RESET** section). **!\<**_r_**e**_s_ : Like the above, but will execute register *s* if the comparison fails. If either or both of the values are not numbers, dc(1) will raise an error and reset (see the **RESET** section). This is a **non-portable extension**. **=**_r_ : Pops two values off of the stack that must be numbers and compares them. If the first value is equal to the second, then the contents of register *r* are executed. If either or both of the values are not numbers, dc(1) will raise an error and reset (see the **RESET** section). **=**_r_**e**_s_ : Like the above, but will execute register *s* if the comparison fails. If either or both of the values are not numbers, dc(1) will raise an error and reset (see the **RESET** section). This is a **non-portable extension**. **!=**_r_ : Pops two values off of the stack that must be numbers and compares them. If the first value is not equal to the second, then the contents of register *r* are executed. If either or both of the values are not numbers, dc(1) will raise an error and reset (see the **RESET** section). **!=**_r_**e**_s_ : Like the above, but will execute register *s* if the comparison fails. If either or both of the values are not numbers, dc(1) will raise an error and reset (see the **RESET** section). This is a **non-portable extension**. **?** : Reads a line from the **stdin** and executes it. This is to allow macros to request input from users. **q** : During execution of a macro, this exits the execution of that macro and the execution of the macro that executed it. If there are no macros, or only one macro executing, dc(1) exits. **Q** : Pops a value from the stack which must be non-negative and is used the number of macro executions to pop off of the execution stack. If the number of levels to pop is greater than the number of executing macros, dc(1) exits. **,** : Pushes the depth of the execution stack onto the stack. The execution stack is the stack of string executions. The number that is pushed onto the stack is exactly as many as is needed to make dc(1) exit with the **Q** command, so the sequence **,Q** will make dc(1) exit. ## Status These commands query status of the stack or its top value. **Z** : Pops a value off of the stack. If it is a number, calculates the number of significant decimal digits it has and pushes the result. It will push **1** if the argument is **0** with no decimal places. If it is a string, pushes the number of characters the string has. **X** : Pops a value off of the stack. If it is a number, pushes the *scale* of the value onto the stack. If it is a string, pushes **0**. **z** : Pushes the current depth of the stack (before execution of this command) onto the stack. **y**_r_ : Pushes the current stack depth of the register *r* onto the main stack. Because each register has a depth of **1** (with the value **0** in the top item) when dc(1) starts, dc(1) requires that each register's stack must always have at least one item; dc(1) will give an error and reset otherwise (see the **RESET** section). This means that this command will never push **0**. This is a **non-portable extension**. ## Arrays These commands manipulate arrays. **:**_r_ : Pops the top two values off of the stack. The second value will be stored in the array *r* (see the **REGISTERS** section), indexed by the first value. **;**_r_ : Pops the value on top of the stack and uses it as an index into the array *r*. The selected value is then pushed onto the stack. **Y**_r_ : Pushes the length of the array *r* onto the stack. This is a **non-portable extension**. ## Global Settings These commands retrieve global settings. These are the only commands that require multiple specific characters, and all of them begin with the letter **g**. Only the characters below are allowed after the character **g**; any other character produces a parse error (see the **ERRORS** section). **gl** : Pushes the line length set by **DC_LINE_LENGTH** (see the **ENVIRONMENT VARIABLES** section) onto the stack. **gz** : Pushes **0** onto the stack if the leading zero setting has not been enabled with the **-z** or **-\-leading-zeroes** options (see the **OPTIONS** section), non-zero otherwise. # REGISTERS Registers are names that can store strings, numbers, and arrays. (Number/string registers do not interfere with array registers.) Each register is also its own stack, so the current register value is the top of the stack for the register. All registers, when first referenced, have one value (**0**) in their stack, and it is a runtime error to attempt to pop that item off of the register stack. In non-extended register mode, a register name is just the single character that follows any command that needs a register name. The only exceptions are: a newline (**'\\n'**) and a left bracket (**'['**); it is a parse error for a newline or a left bracket to be used as a register name. ## Extended Register Mode Unlike most other dc(1) implentations, this dc(1) provides nearly unlimited amounts of registers, if extended register mode is enabled. If extended register mode is enabled (**-x** or **-\-extended-register** command-line arguments are given), then normal single character registers are used *unless* the character immediately following a command that needs a register name is a space (according to **isspace()**) and not a newline (**'\\n'**). In that case, the register name is found according to the regex **\[a-z\]\[a-z0-9\_\]\*** (like bc(1) identifiers), and it is a parse error if the next non-space characters do not match that regex. # RESET When dc(1) encounters an error or a signal that it has a non-default handler for, it resets. This means that several things happen. First, any macros that are executing are stopped and popped off the stack. The behavior is not unlike that of exceptions in programming languages. Then the execution point is set so that any code waiting to execute (after all macros returned) is skipped. Thus, when dc(1) resets, it skips any remaining code waiting to be executed. Then, if it is interactive mode, and the error was not a fatal error (see the **EXIT STATUS** section), it asks for more input; otherwise, it exits with the appropriate return code. # PERFORMANCE Most dc(1) implementations use **char** types to calculate the value of **1** decimal digit at a time, but that can be slow. This dc(1) does something different. It uses large integers to calculate more than **1** decimal digit at a time. If built in a environment where **DC_LONG_BIT** (see the **LIMITS** section) is **64**, then each integer has **9** decimal digits. If built in an environment where **DC_LONG_BIT** is **32** then each integer has **4** decimal digits. This value (the number of decimal digits per large integer) is called **DC_BASE_DIGS**. In addition, this dc(1) uses an even larger integer for overflow checking. This integer type depends on the value of **DC_LONG_BIT**, but is always at least twice as large as the integer type used to store digits. # LIMITS The following are the limits on dc(1): **DC_LONG_BIT** : The number of bits in the **long** type in the environment where dc(1) was built. This determines how many decimal digits can be stored in a single large integer (see the **PERFORMANCE** section). **DC_BASE_DIGS** : The number of decimal digits per large integer (see the **PERFORMANCE** section). Depends on **DC_LONG_BIT**. **DC_BASE_POW** : The max decimal number that each large integer can store (see **DC_BASE_DIGS**) plus **1**. Depends on **DC_BASE_DIGS**. **DC_OVERFLOW_MAX** : The max number that the overflow type (see the **PERFORMANCE** section) can hold. Depends on **DC_LONG_BIT**. **DC_BASE_MAX** : The maximum output base. Set at **DC_BASE_POW**. **DC_DIM_MAX** : The maximum size of arrays. Set at **SIZE_MAX-1**. **DC_SCALE_MAX** : The maximum **scale**. Set at **DC_OVERFLOW_MAX-1**. **DC_STRING_MAX** : The maximum length of strings. Set at **DC_OVERFLOW_MAX-1**. **DC_NAME_MAX** : The maximum length of identifiers. Set at **DC_OVERFLOW_MAX-1**. **DC_NUM_MAX** : The maximum length of a number (in decimal digits), which includes digits after the decimal point. Set at **DC_OVERFLOW_MAX-1**. **DC_RAND_MAX** : The maximum integer (inclusive) returned by the **'** command, if dc(1). Set at **2\^DC_LONG_BIT-1**. Exponent : The maximum allowable exponent (positive or negative). Set at **DC_OVERFLOW_MAX**. Number of vars : The maximum number of vars/arrays. Set at **SIZE_MAX-1**. These limits are meant to be effectively non-existent; the limits are so large (at least on 64-bit machines) that there should not be any point at which they become a problem. In fact, memory should be exhausted before these limits should be hit. # ENVIRONMENT VARIABLES dc(1) recognizes the following environment variables: **DC_ENV_ARGS** : This is another way to give command-line arguments to dc(1). They should be in the same format as all other command-line arguments. These are always processed first, so any files given in **DC_ENV_ARGS** will be processed before arguments and files given on the command-line. This gives the user the ability to set up "standard" options and files to be used at every invocation. The most useful thing for such files to contain would be useful functions that the user might want every time dc(1) runs. Another use would be to use the **-e** option to set **scale** to a value other than **0**. The code that parses **DC_ENV_ARGS** will correctly handle quoted arguments, but it does not understand escape sequences. For example, the string **"/home/gavin/some dc file.dc"** will be correctly parsed, but the string **"/home/gavin/some \"dc\" file.dc"** will include the backslashes. The quote parsing will handle either kind of quotes, **'** or **"**. Thus, if you have a file with any number of single quotes in the name, you can use double quotes as the outside quotes, as in **"some 'dc' file.dc"**, and vice versa if you have a file with double quotes. However, handling a file with both kinds of quotes in **DC_ENV_ARGS** is not supported due to the complexity of the parsing, though such files are still supported on the command-line where the parsing is done by the shell. **DC_LINE_LENGTH** : If this environment variable exists and contains an integer that is greater than **1** and is less than **UINT16_MAX** (**2\^16-1**), dc(1) will output lines to that length, including the backslash newline combo. The default line length is **70**. The special value of **0** will disable line length checking and print numbers without regard to line length and without backslashes and newlines. **DC_SIGINT_RESET** : If dc(1) is not in interactive mode (see the **INTERACTIVE MODE** section), then this environment variable has no effect because dc(1) exits on **SIGINT** when not in interactive mode. However, when dc(1) is in interactive mode, then if this environment variable exists and contains an integer, a non-zero value makes dc(1) reset on **SIGINT**, rather than exit, and zero makes dc(1) exit. If this environment variable exists and is *not* an integer, then dc(1) will exit on **SIGINT**. This environment variable overrides the default, which can be queried with the **-h** or **-\-help** options. **DC_TTY_MODE** : If TTY mode is *not* available (see the **TTY MODE** section), then this environment variable has no effect. However, when TTY mode is available, then if this environment variable exists and contains an integer, then a non-zero value makes dc(1) use TTY mode, and zero makes dc(1) not use TTY mode. This environment variable overrides the default, which can be queried with the **-h** or **-\-help** options. **DC_PROMPT** : If TTY mode is *not* available (see the **TTY MODE** section), then this environment variable has no effect. However, when TTY mode is available, then if this environment variable exists and contains an integer, a non-zero value makes dc(1) use a prompt, and zero or a non-integer makes dc(1) not use a prompt. If this environment variable does not exist and **DC_TTY_MODE** does, then the value of the **DC_TTY_MODE** environment variable is used. This environment variable and the **DC_TTY_MODE** environment variable override the default, which can be queried with the **-h** or **-\-help** options. +**DC_EXPR_EXIT** + +: If any expressions or expression files are given on the command-line with + **-e**, **-\-expression**, **-f**, or **-\-file**, then if this environment + variable exists and contains an integer, a non-zero value makes dc(1) exit + after executing the expressions and expression files, and a non-zero value + makes dc(1) not exit. + + This environment variable overrides the default, which can be queried with + the **-h** or **-\-help** options. + # EXIT STATUS dc(1) returns the following exit statuses: **0** : No error. **1** : A math error occurred. This follows standard practice of using **1** for expected errors, since math errors will happen in the process of normal execution. Math errors include divide by **0**, taking the square root of a negative number, using a negative number as a bound for the pseudo-random number generator, attempting to convert a negative number to a hardware integer, overflow when converting a number to a hardware integer, overflow when calculating the size of a number, and attempting to use a non-integer where an integer is required. Converting to a hardware integer happens for the second operand of the power (**\^**), places (**\@**), left shift (**H**), and right shift (**h**) operators. **2** : A parse error occurred. Parse errors include unexpected **EOF**, using an invalid character, failing to find the end of a string or comment, and using a token where it is invalid. **3** : A runtime error occurred. Runtime errors include assigning an invalid number to any global (**ibase**, **obase**, or **scale**), giving a bad expression to a **read()** call, calling **read()** inside of a **read()** call, type errors (including attempting to execute a number), and attempting an operation when the stack has too few elements. **4** : A fatal error occurred. Fatal errors include memory allocation errors, I/O errors, failing to open files, attempting to use files that do not have only ASCII characters (dc(1) only accepts ASCII characters), attempting to open a directory as a file, and giving invalid command-line options. The exit status **4** is special; when a fatal error occurs, dc(1) always exits and returns **4**, no matter what mode dc(1) is in. The other statuses will only be returned when dc(1) is not in interactive mode (see the **INTERACTIVE MODE** section), since dc(1) resets its state (see the **RESET** section) and accepts more input when one of those errors occurs in interactive mode. This is also the case when interactive mode is forced by the **-i** flag or **-\-interactive** option. These exit statuses allow dc(1) to be used in shell scripting with error checking, and its normal behavior can be forced by using the **-i** flag or **-\-interactive** option. # INTERACTIVE MODE Like bc(1), dc(1) has an interactive mode and a non-interactive mode. Interactive mode is turned on automatically when both **stdin** and **stdout** are hooked to a terminal, but the **-i** flag and **-\-interactive** option can turn it on in other situations. In interactive mode, dc(1) attempts to recover from errors (see the **RESET** section), and in normal execution, flushes **stdout** as soon as execution is done for the current input. dc(1) may also reset on **SIGINT** instead of exit, depending on the contents of, or default for, the **DC_SIGINT_RESET** environment variable (see the **ENVIRONMENT VARIABLES** section). # TTY MODE If **stdin**, **stdout**, and **stderr** are all connected to a TTY, then "TTY mode" is considered to be available, and thus, dc(1) can turn on TTY mode, subject to some settings. If there is the environment variable **DC_TTY_MODE** in the environment (see the **ENVIRONMENT VARIABLES** section), then if that environment variable contains a non-zero integer, dc(1) will turn on TTY mode when **stdin**, **stdout**, and **stderr** are all connected to a TTY. If the **DC_TTY_MODE** environment variable exists but is *not* a non-zero integer, then dc(1) will not turn TTY mode on. If the environment variable **DC_TTY_MODE** does *not* exist, the default setting is used. The default setting can be queried with the **-h** or **-\-help** options. TTY mode is different from interactive mode because interactive mode is required in the [bc(1) specification][1], and interactive mode requires only **stdin** and **stdout** to be connected to a terminal. ## Command-Line History Command-line history is only enabled if TTY mode is, i.e., that **stdin**, **stdout**, and **stderr** are connected to a TTY and the **DC_TTY_MODE** environment variable (see the **ENVIRONMENT VARIABLES** section) and its default do not disable TTY mode. See the **COMMAND LINE HISTORY** section for more information. ## Prompt If TTY mode is available, then a prompt can be enabled. Like TTY mode itself, it can be turned on or off with an environment variable: **DC_PROMPT** (see the **ENVIRONMENT VARIABLES** section). If the environment variable **DC_PROMPT** exists and is a non-zero integer, then the prompt is turned on when **stdin**, **stdout**, and **stderr** are connected to a TTY and the **-P** and **-\-no-prompt** options were not used. The read prompt will be turned on under the same conditions, except that the **-R** and **-\-no-read-prompt** options must also not be used. However, if **DC_PROMPT** does not exist, the prompt can be enabled or disabled with the **DC_TTY_MODE** environment variable, the **-P** and **-\-no-prompt** options, and the **-R** and **-\-no-read-prompt** options. See the **ENVIRONMENT VARIABLES** and **OPTIONS** sections for more details. # SIGNAL HANDLING Sending a **SIGINT** will cause dc(1) to do one of two things. If dc(1) is not in interactive mode (see the **INTERACTIVE MODE** section), or the **DC_SIGINT_RESET** environment variable (see the **ENVIRONMENT VARIABLES** section), or its default, is either not an integer or it is zero, dc(1) will exit. However, if dc(1) is in interactive mode, and the **DC_SIGINT_RESET** or its default is an integer and non-zero, then dc(1) will stop executing the current input and reset (see the **RESET** section) upon receiving a **SIGINT**. Note that "current input" can mean one of two things. If dc(1) is processing input from **stdin** in interactive mode, it will ask for more input. If dc(1) is processing input from a file in interactive mode, it will stop processing the file and start processing the next file, if one exists, or ask for input from **stdin** if no other file exists. This means that if a **SIGINT** is sent to dc(1) as it is executing a file, it can seem as though dc(1) did not respond to the signal since it will immediately start executing the next file. This is by design; most files that users execute when interacting with dc(1) have function definitions, which are quick to parse. If a file takes a long time to execute, there may be a bug in that file. The rest of the files could still be executed without problem, allowing the user to continue. **SIGTERM** and **SIGQUIT** cause dc(1) to clean up and exit, and it uses the default handler for all other signals. The one exception is **SIGHUP**; in that case, and only when dc(1) is in TTY mode (see the **TTY MODE** section), a **SIGHUP** will cause dc(1) to clean up and exit. # COMMAND LINE HISTORY dc(1) supports interactive command-line editing. If dc(1) can be in TTY mode (see the **TTY MODE** section), history can be enabled. This means that command-line history can only be enabled when **stdin**, **stdout**, and **stderr** are all connected to a TTY. Like TTY mode itself, it can be turned on or off with the environment variable **DC_TTY_MODE** (see the **ENVIRONMENT VARIABLES** section). **Note**: tabs are converted to 8 spaces. # SEE ALSO bc(1) # STANDARDS The dc(1) utility operators are compliant with the operators in the bc(1) [IEEE Std 1003.1-2017 (“POSIX.1-2017”)][1] specification. # BUGS None are known. Report bugs at https://git.yzena.com/gavin/bc. # AUTHOR Gavin D. Howard and contributors. [1]: https://pubs.opengroup.org/onlinepubs/9699919799/utilities/bc.html diff --git a/contrib/bc/scripts/exec-install.sh b/contrib/bc/scripts/exec-install.sh index 25d56c6fc688..f36caa37e6f8 100755 --- a/contrib/bc/scripts/exec-install.sh +++ b/contrib/bc/scripts/exec-install.sh @@ -1,67 +1,72 @@ #! /bin/sh # # SPDX-License-Identifier: BSD-2-Clause # # Copyright (c) 2018-2021 Gavin D. Howard and contributors. # # Redistribution and use in source and binary forms, with or without # modification, are permitted provided that the following conditions are met: # # * Redistributions of source code must retain the above copyright notice, this # list of conditions and the following disclaimer. # # * Redistributions in binary form must reproduce the above copyright notice, # this list of conditions and the following disclaimer in the documentation # and/or other materials provided with the distribution. # # THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" # AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE # IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE # ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE # LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR # CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF # SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS # INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN # CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) # ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE # POSSIBILITY OF SUCH DAMAGE. # # Print usage and exit with an error. usage() { - printf "usage: %s install_dir exec_suffix\n" "$0" 1>&2 + printf "usage: %s install_dir exec_suffix [bindir]\n" "$0" 1>&2 exit 1 } script="$0" scriptdir=$(dirname "$script") . "$scriptdir/functions.sh" INSTALL="$scriptdir/safe-install.sh" # Process command-line arguments. test "$#" -ge 2 || usage installdir="$1" shift exec_suffix="$1" shift -bindir="$scriptdir/../bin" +if [ "$#" -gt 0 ]; then + bindir="$1" + shift +else + bindir="$scriptdir/../bin" +fi # Install or symlink, depending on the type of file. If it's a file, install it. # If it's a symlink, create an equivalent in the install directory. for exe in $bindir/*; do base=$(basename "$exe") if [ -L "$exe" ]; then link=$(readlink "$exe") "$INSTALL" -Dlm 755 "$link$exec_suffix" "$installdir/$base$exec_suffix" else "$INSTALL" -Dm 755 "$exe" "$installdir/$base$exec_suffix" fi done diff --git a/contrib/bc/scripts/karatsuba.py b/contrib/bc/scripts/karatsuba.py index b8505186b526..9aa1c2a5457f 100755 --- a/contrib/bc/scripts/karatsuba.py +++ b/contrib/bc/scripts/karatsuba.py @@ -1,255 +1,252 @@ #! /usr/bin/python3 -B # # SPDX-License-Identifier: BSD-2-Clause # # Copyright (c) 2018-2021 Gavin D. Howard and contributors. # # Redistribution and use in source and binary forms, with or without # modification, are permitted provided that the following conditions are met: # # * Redistributions of source code must retain the above copyright notice, this # list of conditions and the following disclaimer. # # * Redistributions in binary form must reproduce the above copyright notice, # this list of conditions and the following disclaimer in the documentation # and/or other materials provided with the distribution. # # THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" # AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE # IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE # ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE # LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR # CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF # SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS # INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN # CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) # ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE # POSSIBILITY OF SUCH DAMAGE. # import os import sys import subprocess import time # Print the usage and exit with an error. def usage(): print("usage: {} [num_iterations test_num exe]".format(script)) print("\n num_iterations is the number of times to run each karatsuba number; default is 4") print("\n test_num is the last Karatsuba number to run through tests") sys.exit(1) # Run a command. This is basically an alias. def run(cmd, env=None): return subprocess.run(cmd, stdout=subprocess.PIPE, stderr=subprocess.PIPE, env=env) script = sys.argv[0] testdir = os.path.dirname(script) if testdir == "": testdir = os.getcwd() -# We want to be in the root directory. -os.chdir(testdir + "/..") - print("\nWARNING: This script is for distro and package maintainers.") print("It is for finding the optimal Karatsuba number.") print("Though it only needs to be run once per release/platform,") print("it takes forever to run.") print("You have been warned.\n") print("Note: If you send an interrupt, it will report the current best number.\n") # This script has to be run by itself. if __name__ != "__main__": usage() # These constants can be changed, but I found they work well enough. mx = 520 mx2 = mx // 2 mn = 16 num = "9" * mx args_idx = 4 # Command-line processing. if len(sys.argv) >= 2: num_iterations = int(sys.argv[1]) else: num_iterations = 4 if len(sys.argv) >= 3: test_num = int(sys.argv[2]) else: test_num = 0 if len(sys.argv) >= args_idx: exe = sys.argv[3] else: exe = testdir + "/bin/bc" exedir = os.path.dirname(exe) # Some basic tests. indata = "for (i = 0; i < 100; ++i) {} * {}\n" indata += "1.23456789^100000\n1.23456789^100000\nhalt" indata = indata.format(num, num).encode() times = [] nums = [] runs = [] nruns = num_iterations + 1 # We build the list first because I want to just edit slots. for i in range(0, nruns): runs.append(0) tests = [ "multiply", "modulus", "power", "sqrt" ] scripts = [ "multiply" ] # Test Link-Time Optimization. print("Testing CFLAGS=\"-flto\"...") flags = dict(os.environ) try: flags["CFLAGS"] = flags["CFLAGS"] + " " + "-flto" except KeyError: flags["CFLAGS"] = "-flto" -p = run([ "./configure.sh", "-O3" ], flags) +p = run([ "{}/../configure.sh".format(testdir), "-O3" ], flags) if p.returncode != 0: print("configure.sh returned an error ({}); exiting...".format(p.returncode)) sys.exit(p.returncode) p = run([ "make" ]) if p.returncode == 0: config_env = flags print("Using CFLAGS=\"-flto\"") else: config_env = os.environ print("Not using CFLAGS=\"-flto\"") p = run([ "make", "clean" ]) # Test parallel build. My machine has 16 cores. print("Testing \"make -j16\"") if p.returncode != 0: print("make returned an error ({}); exiting...".format(p.returncode)) sys.exit(p.returncode) p = run([ "make", "-j16" ]) if p.returncode == 0: makecmd = [ "make", "-j16" ] print("Using \"make -j16\"") else: makecmd = [ "make" ] print("Not using \"make -j16\"") # Set the max if the user did. if test_num != 0: mx2 = test_num # This is the meat here. try: # For each possible KARATSUBA_LEN... for i in range(mn, mx2 + 1): # Configure and compile. print("\nCompiling...\n") - p = run([ "./configure.sh", "-O3", "-k{}".format(i) ], config_env) + p = run([ "{}/../configure.sh".format(testdir), "-O3", "-k{}".format(i) ], config_env) if p.returncode != 0: print("configure.sh returned an error ({}); exiting...".format(p.returncode)) sys.exit(p.returncode) p = run(makecmd) if p.returncode != 0: print("make returned an error ({}); exiting...".format(p.returncode)) sys.exit(p.returncode) # Test if desired. if (test_num >= i): print("Running tests for Karatsuba Num: {}\n".format(i)) for test in tests: cmd = [ "{}/../tests/test.sh".format(testdir), "bc", test, "0", "0", exe ] p = subprocess.run(cmd + sys.argv[args_idx:], stderr=subprocess.PIPE) if p.returncode != 0: print("{} test failed:\n".format(test, p.returncode)) print(p.stderr.decode()) print("\nexiting...") sys.exit(p.returncode) print("") for script in scripts: cmd = [ "{}/../tests/script.sh".format(testdir), "bc", script + ".bc", "0", "1", "1", "0", exe ] p = subprocess.run(cmd + sys.argv[args_idx:], stderr=subprocess.PIPE) if p.returncode != 0: print("{} test failed:\n".format(test, p.returncode)) print(p.stderr.decode()) print("\nexiting...") sys.exit(p.returncode) print("") # If testing was *not* desired, assume the user wanted to time it. elif test_num == 0: print("Timing Karatsuba Num: {}".format(i), end='', flush=True) for j in range(0, nruns): cmd = [ exe, "{}/../tests/bc/power.txt".format(testdir) ] start = time.perf_counter() p = subprocess.run(cmd, input=indata, stdout=subprocess.PIPE, stderr=subprocess.PIPE) end = time.perf_counter() if p.returncode != 0: print("bc returned an error; exiting...") sys.exit(p.returncode) runs[j] = end - start run_times = runs[1:] avg = sum(run_times) / len(run_times) times.append(avg) nums.append(i) print(", Time: {}".format(times[i - mn])) except KeyboardInterrupt: # When timing, we want to quit when the user tells us to. However, we also # want to report the best run, so we make sure to grab the times here before # moving on. nums = nums[0:i] times = times[0:i] # If running timed tests... if test_num == 0: # Report the optimal KARATSUBA_LEN opt = nums[times.index(min(times))] print("\n\nOptimal Karatsuba Num (for this machine): {}".format(opt)) print("Run the following:\n") if "-flto" in config_env["CFLAGS"]: print("CFLAGS=\"-flto\" ./configure.sh -O3 -k {}".format(opt)) else: print("./configure.sh -O3 -k {}".format(opt)) print("make") diff --git a/contrib/bc/src/args.c b/contrib/bc/src/args.c index 6601cfb2eeb6..5eee96f5b559 100644 --- a/contrib/bc/src/args.c +++ b/contrib/bc/src/args.c @@ -1,288 +1,290 @@ /* * ***************************************************************************** * * SPDX-License-Identifier: BSD-2-Clause * * Copyright (c) 2018-2021 Gavin D. Howard and contributors. * * Redistribution and use in source and binary forms, with or without * modification, are permitted provided that the following conditions are met: * * * Redistributions of source code must retain the above copyright notice, this * list of conditions and the following disclaimer. * * * Redistributions in binary form must reproduce the above copyright notice, * this list of conditions and the following disclaimer in the documentation * and/or other materials provided with the distribution. * * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE * POSSIBILITY OF SUCH DAMAGE. * * ***************************************************************************** * * Code for processing command-line arguments. * */ #include #include #include #include #include #ifndef _WIN32 #include #endif // _WIN32 #include #include #include #include /** * Adds @a str to the list of expressions to execute later. * @param str The string to add to the list of expressions. */ static void bc_args_exprs(const char *str) { BC_SIG_ASSERT_LOCKED; if (vm.exprs.v == NULL) bc_vec_init(&vm.exprs, sizeof(uchar), BC_DTOR_NONE); bc_vec_concat(&vm.exprs, str); bc_vec_concat(&vm.exprs, "\n"); } /** * Adds the contents of @a file to the list of expressions to execute later. * @param file The name of the file whose contents should be added to the list * of expressions to execute. */ static void bc_args_file(const char *file) { char *buf; BC_SIG_ASSERT_LOCKED; vm.file = file; buf = bc_read_file(file); assert(buf != NULL); bc_args_exprs(buf); free(buf); } #if BC_ENABLED /** * Redefines a keyword, if it exists and is not a POSIX keyword. Otherwise, it * throws a fatal error. * @param keyword The keyword to redefine. */ static void bc_args_redefine(const char *keyword) { size_t i; + BC_SIG_ASSERT_LOCKED; + for (i = 0; i < bc_lex_kws_len; ++i) { const BcLexKeyword *kw = bc_lex_kws + i; if (!strcmp(keyword, kw->name)) { if (BC_LEX_KW_POSIX(kw)) break; vm.redefined_kws[i] = true; return; } } bc_error(BC_ERR_FATAL_ARG, 0, keyword); } #endif // BC_ENABLED void bc_args(int argc, char *argv[], bool exit_exprs) { int c; size_t i; bool do_exit = false, version = false; BcOpt opts; BC_SIG_ASSERT_LOCKED; bc_opt_init(&opts, argv); // This loop should look familiar to anyone who has used getopt() or // getopt_long() in C. while ((c = bc_opt_parse(&opts, bc_args_lopt)) != -1) { switch (c) { case 'e': { // Barf if not allowed. if (vm.no_exprs) bc_verr(BC_ERR_FATAL_OPTION, "-e (--expression)"); // Add the expressions and set exit. bc_args_exprs(opts.optarg); vm.exit_exprs = (exit_exprs || vm.exit_exprs); break; } case 'f': { // Figure out if exiting on expressions is disabled. if (!strcmp(opts.optarg, "-")) vm.no_exprs = true; else { // Barf if not allowed. if (vm.no_exprs) bc_verr(BC_ERR_FATAL_OPTION, "-f (--file)"); // Add the expressions and set exit. bc_args_file(opts.optarg); vm.exit_exprs = (exit_exprs || vm.exit_exprs); } break; } case 'h': { bc_vm_info(vm.help); do_exit = true; break; } case 'i': { vm.flags |= BC_FLAG_I; break; } case 'z': { vm.flags |= BC_FLAG_Z; break; } case 'L': { vm.line_len = 0; break; } case 'P': { vm.flags &= ~(BC_FLAG_P); break; } case 'R': { vm.flags &= ~(BC_FLAG_R); break; } #if BC_ENABLED case 'g': { assert(BC_IS_BC); vm.flags |= BC_FLAG_G; break; } case 'l': { assert(BC_IS_BC); vm.flags |= BC_FLAG_L; break; } case 'q': { assert(BC_IS_BC); vm.flags &= ~(BC_FLAG_Q); break; } case 'r': { bc_args_redefine(opts.optarg); break; } case 's': { assert(BC_IS_BC); vm.flags |= BC_FLAG_S; break; } case 'w': { assert(BC_IS_BC); vm.flags |= BC_FLAG_W; break; } #endif // BC_ENABLED case 'V': case 'v': { do_exit = version = true; break; } #if DC_ENABLED case 'x': { assert(BC_IS_DC); vm.flags |= DC_FLAG_X; break; } #endif // DC_ENABLED #ifndef NDEBUG // We shouldn't get here because bc_opt_error()/bc_error() should // longjmp() out. case '?': case ':': default: { BC_UNREACHABLE abort(); } #endif // NDEBUG } } if (version) bc_vm_info(NULL); if (do_exit) { vm.status = (sig_atomic_t) BC_STATUS_QUIT; BC_JMP; } // We do not print the banner if expressions are used or dc is used. if (!BC_IS_BC || vm.exprs.len > 1) vm.flags &= ~(BC_FLAG_Q); // We need to make sure the files list is initialized. We don't want to // initialize it if there are no files because it's just a waste of memory. if (opts.optind < (size_t) argc && vm.files.v == NULL) bc_vec_init(&vm.files, sizeof(char*), BC_DTOR_NONE); // Add all the files to the vector. for (i = opts.optind; i < (size_t) argc; ++i) bc_vec_push(&vm.files, argv + i); } diff --git a/contrib/bc/src/bc_lex.c b/contrib/bc/src/bc_lex.c index cdbdf24b17ac..bd03d169ee06 100644 --- a/contrib/bc/src/bc_lex.c +++ b/contrib/bc/src/bc_lex.c @@ -1,479 +1,481 @@ /* * ***************************************************************************** * * SPDX-License-Identifier: BSD-2-Clause * * Copyright (c) 2018-2021 Gavin D. Howard and contributors. * * Redistribution and use in source and binary forms, with or without * modification, are permitted provided that the following conditions are met: * * * Redistributions of source code must retain the above copyright notice, this * list of conditions and the following disclaimer. * * * Redistributions in binary form must reproduce the above copyright notice, * this list of conditions and the following disclaimer in the documentation * and/or other materials provided with the distribution. * * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE * POSSIBILITY OF SUCH DAMAGE. * * ***************************************************************************** * * The lexer for bc. * */ #if BC_ENABLED #include #include #include #include #include /** * Lexes an identifier, which may be a keyword. * @param l The lexer. */ static void bc_lex_identifier(BcLex *l) { // We already passed the first character, so we need to be sure to include // it. const char *buf = l->buf + l->i - 1; size_t i; // This loop is simply checking for keywords. for (i = 0; i < bc_lex_kws_len; ++i) { const BcLexKeyword *kw = bc_lex_kws + i; size_t n = BC_LEX_KW_LEN(kw); if (!strncmp(buf, kw->name, n) && !isalnum(buf[n]) && buf[n] != '_') { // If the keyword has been redefined, and redefinition is allowed // (it is not allowed for builtin libraries), break out of the loop // and use it as a name. This depends on the argument parser to // ensure that only non-POSIX keywords get redefined. if (!vm.no_redefine && vm.redefined_kws[i]) break; l->t = BC_LEX_KW_AUTO + (BcLexType) i; // Warn or error, as appropriate for the mode, if the keyword is not // in the POSIX standard. if (!BC_LEX_KW_POSIX(kw)) bc_lex_verr(l, BC_ERR_POSIX_KW, kw->name); // We minus 1 because the index has already been incremented. l->i += n - 1; // Already have the token; bail. return; } } // If not a keyword, parse the name. bc_lex_name(l); // POSIX doesn't allow identifiers that are more than one character, so we // might have to warn or error here too. if (BC_ERR(l->str.len - 1 > 1)) bc_lex_verr(l, BC_ERR_POSIX_NAME_LEN, l->str.v); } /** * Parses a bc string. This is separate from dc strings because dc strings need * to be balanced. * @param l The lexer. */ static void bc_lex_string(BcLex *l) { // We need to keep track of newlines to increment them properly. size_t len, nlines, i; const char *buf; char c; bool got_more; l->t = BC_LEX_STR; do { nlines = 0; buf = l->buf; got_more = false; assert(!vm.is_stdin || buf == vm.buffer.v); // Fortunately for us, bc doesn't escape quotes. Instead, the equivalent // is '\q', which makes this loop simpler. for (i = l->i; (c = buf[i]) && c != '"'; ++i) nlines += (c == '\n'); if (BC_ERR(c == '\0') && !vm.eof && l->is_stdin) got_more = bc_lex_readLine(l); } while (got_more && c != '"'); // If the string did not end properly, barf. if (c != '"') { l->i = i; bc_lex_err(l, BC_ERR_PARSE_STRING); } // Set the temp string to the parsed string. len = i - l->i; bc_vec_string(&l->str, len, l->buf + l->i); l->i = i + 1; l->line += nlines; } /** * This function takes a lexed operator and checks to see if it's the assignment * version, setting the token appropriately. * @param l The lexer. * @param with The token to assign if it is an assignment operator. * @param without The token to assign if it is not an assignment operator. */ static void bc_lex_assign(BcLex *l, BcLexType with, BcLexType without) { if (l->buf[l->i] == '=') { l->i += 1; l->t = with; } else l->t = without; } void bc_lex_token(BcLex *l) { // We increment here. This means that all lexing needs to take that into // account, such as when parsing an identifier. If we don't, the first // character of every identifier would be missing. char c = l->buf[l->i++], c2; + BC_SIG_ASSERT_LOCKED; + // This is the workhorse of the lexer. switch (c) { case '\0': case '\n': case '\t': case '\v': case '\f': case '\r': case ' ': { bc_lex_commonTokens(l, c); break; } case '!': { // Even though it's not an assignment, we can use this. bc_lex_assign(l, BC_LEX_OP_REL_NE, BC_LEX_OP_BOOL_NOT); // POSIX doesn't allow boolean not. if (l->t == BC_LEX_OP_BOOL_NOT) bc_lex_verr(l, BC_ERR_POSIX_BOOL, "!"); break; } case '"': { bc_lex_string(l); break; } case '#': { // POSIX does not allow line comments. bc_lex_err(l, BC_ERR_POSIX_COMMENT); bc_lex_lineComment(l); break; } case '%': { bc_lex_assign(l, BC_LEX_OP_ASSIGN_MODULUS, BC_LEX_OP_MODULUS); break; } case '&': { c2 = l->buf[l->i]; // Either we have boolean and or an error. And boolean and is not // allowed by POSIX. if (BC_NO_ERR(c2 == '&')) { bc_lex_verr(l, BC_ERR_POSIX_BOOL, "&&"); l->i += 1; l->t = BC_LEX_OP_BOOL_AND; } else bc_lex_invalidChar(l, c); break; } #if BC_ENABLE_EXTRA_MATH case '$': { l->t = BC_LEX_OP_TRUNC; break; } case '@': { bc_lex_assign(l, BC_LEX_OP_ASSIGN_PLACES, BC_LEX_OP_PLACES); break; } #endif // BC_ENABLE_EXTRA_MATH case '(': case ')': { l->t = (BcLexType) (c - '(' + BC_LEX_LPAREN); break; } case '*': { bc_lex_assign(l, BC_LEX_OP_ASSIGN_MULTIPLY, BC_LEX_OP_MULTIPLY); break; } case '+': { c2 = l->buf[l->i]; // Have to check for increment first. if (c2 == '+') { l->i += 1; l->t = BC_LEX_OP_INC; } else bc_lex_assign(l, BC_LEX_OP_ASSIGN_PLUS, BC_LEX_OP_PLUS); break; } case ',': { l->t = BC_LEX_COMMA; break; } case '-': { c2 = l->buf[l->i]; // Have to check for decrement first. if (c2 == '-') { l->i += 1; l->t = BC_LEX_OP_DEC; } else bc_lex_assign(l, BC_LEX_OP_ASSIGN_MINUS, BC_LEX_OP_MINUS); break; } case '.': { c2 = l->buf[l->i]; // If it's alone, it's an alias for last. if (BC_LEX_NUM_CHAR(c2, true, false)) bc_lex_number(l, c); else { l->t = BC_LEX_KW_LAST; bc_lex_err(l, BC_ERR_POSIX_DOT); } break; } case '/': { c2 = l->buf[l->i]; if (c2 =='*') bc_lex_comment(l); else bc_lex_assign(l, BC_LEX_OP_ASSIGN_DIVIDE, BC_LEX_OP_DIVIDE); break; } case '0': case '1': case '2': case '3': case '4': case '5': case '6': case '7': case '8': case '9': case 'A': case 'B': case 'C': case 'D': case 'E': case 'F': // Apparently, GNU bc (and maybe others) allows any uppercase letter as // a number. When single digits, they act like the ones above. When // multi-digit, any letter above the input base is automatically set to // the biggest allowable digit in the input base. case 'G': case 'H': case 'I': case 'J': case 'K': case 'L': case 'M': case 'N': case 'O': case 'P': case 'Q': case 'R': case 'S': case 'T': case 'U': case 'V': case 'W': case 'X': case 'Y': case 'Z': { bc_lex_number(l, c); break; } case ';': { l->t = BC_LEX_SCOLON; break; } case '<': { #if BC_ENABLE_EXTRA_MATH c2 = l->buf[l->i]; // Check for shift. if (c2 == '<') { l->i += 1; bc_lex_assign(l, BC_LEX_OP_ASSIGN_LSHIFT, BC_LEX_OP_LSHIFT); break; } #endif // BC_ENABLE_EXTRA_MATH bc_lex_assign(l, BC_LEX_OP_REL_LE, BC_LEX_OP_REL_LT); break; } case '=': { bc_lex_assign(l, BC_LEX_OP_REL_EQ, BC_LEX_OP_ASSIGN); break; } case '>': { #if BC_ENABLE_EXTRA_MATH c2 = l->buf[l->i]; // Check for shift. if (c2 == '>') { l->i += 1; bc_lex_assign(l, BC_LEX_OP_ASSIGN_RSHIFT, BC_LEX_OP_RSHIFT); break; } #endif // BC_ENABLE_EXTRA_MATH bc_lex_assign(l, BC_LEX_OP_REL_GE, BC_LEX_OP_REL_GT); break; } case '[': case ']': { l->t = (BcLexType) (c - '[' + BC_LEX_LBRACKET); break; } case '\\': { // In bc, a backslash+newline is whitespace. if (BC_NO_ERR(l->buf[l->i] == '\n')) { l->i += 1; l->t = BC_LEX_WHITESPACE; } else bc_lex_invalidChar(l, c); break; } case '^': { bc_lex_assign(l, BC_LEX_OP_ASSIGN_POWER, BC_LEX_OP_POWER); break; } case 'a': case 'b': case 'c': case 'd': case 'e': case 'f': case 'g': case 'h': case 'i': case 'j': case 'k': case 'l': case 'm': case 'n': case 'o': case 'p': case 'q': case 'r': case 's': case 't': case 'u': case 'v': case 'w': case 'x': case 'y': case 'z': { bc_lex_identifier(l); break; } case '{': case '}': { l->t = (BcLexType) (c - '{' + BC_LEX_LBRACE); break; } case '|': { c2 = l->buf[l->i]; // Once again, boolean or is not allowed by POSIX. if (BC_NO_ERR(c2 == '|')) { bc_lex_verr(l, BC_ERR_POSIX_BOOL, "||"); l->i += 1; l->t = BC_LEX_OP_BOOL_OR; } else bc_lex_invalidChar(l, c); break; } default: { bc_lex_invalidChar(l, c); } } } #endif // BC_ENABLED diff --git a/contrib/bc/src/bc_parse.c b/contrib/bc/src/bc_parse.c index c2fc2186a065..8849c1b8e9c7 100644 --- a/contrib/bc/src/bc_parse.c +++ b/contrib/bc/src/bc_parse.c @@ -1,2313 +1,2326 @@ /* * ***************************************************************************** * * SPDX-License-Identifier: BSD-2-Clause * * Copyright (c) 2018-2021 Gavin D. Howard and contributors. * * Redistribution and use in source and binary forms, with or without * modification, are permitted provided that the following conditions are met: * * * Redistributions of source code must retain the above copyright notice, this * list of conditions and the following disclaimer. * * * Redistributions in binary form must reproduce the above copyright notice, * this list of conditions and the following disclaimer in the documentation * and/or other materials provided with the distribution. * * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE * POSSIBILITY OF SUCH DAMAGE. * * ***************************************************************************** * * The parser for bc. * */ #if BC_ENABLED #include #include #include #include #include #include #include #include // Before you embark on trying to understand this code, have you read the // Development manual (manuals/development.md) and the comment in include/bc.h // yet? No? Do that first. I'm serious. // // The reason is because this file holds the most sensitive and finicky code in // the entire codebase. Even getting history to work on Windows was nothing // compared to this. This is where dreams go to die, where dragons live, and // from which Ken Thompson himself would flee. static void bc_parse_else(BcParse *p); static void bc_parse_stmt(BcParse *p); static BcParseStatus bc_parse_expr_err(BcParse *p, uint8_t flags, BcParseNext next); static void bc_parse_expr_status(BcParse *p, uint8_t flags, BcParseNext next); /** * Returns true if an instruction could only have come from a "leaf" expression. * For more on what leaf expressions are, read the comment for BC_PARSE_LEAF(). * @param t The instruction to test. */ static bool bc_parse_inst_isLeaf(BcInst t) { return (t >= BC_INST_NUM && t <= BC_INST_MAXSCALE) || #if BC_ENABLE_EXTRA_MATH t == BC_INST_TRUNC || #endif // BC_ENABLE_EXTRA_MATH t <= BC_INST_DEC; } /** * Returns true if the *previous* token was a delimiter. A delimiter is anything * that can legally end a statement. In bc's case, it could be a newline, a * semicolon, and a brace in certain cases. * @param p The parser. + * @return True if the token is a legal delimiter. */ static bool bc_parse_isDelimiter(const BcParse *p) { BcLexType t = p->l.t; bool good; // If it's an obvious delimiter, say so. if (BC_PARSE_DELIMITER(t)) return true; good = false; // If the current token is a keyword, then...beware. That means that we need // to check for a "dangling" else, where there was no brace-delimited block // on the previous if. if (t == BC_LEX_KW_ELSE) { size_t i; uint16_t *fptr = NULL, flags = BC_PARSE_FLAG_ELSE; // As long as going up the stack is valid for a dangling else, keep on. for (i = 0; i < p->flags.len && BC_PARSE_BLOCK_STMT(flags); ++i) { fptr = bc_vec_item_rev(&p->flags, i); flags = *fptr; // If we need a brace and don't have one, then we don't have a // delimiter. if ((flags & BC_PARSE_FLAG_BRACE) && p->l.last != BC_LEX_RBRACE) return false; } // Oh, and we had also better have an if statement somewhere. good = ((flags & BC_PARSE_FLAG_IF) != 0); } else if (t == BC_LEX_RBRACE) { size_t i; // Since we have a brace, we need to just check if a brace was needed. for (i = 0; !good && i < p->flags.len; ++i) { uint16_t *fptr = bc_vec_item_rev(&p->flags, i); good = (((*fptr) & BC_PARSE_FLAG_BRACE) != 0); } } return good; } +/** + * Returns true if we are in top level of a function body. The POSIX grammar + * is defined such that anything is allowed after a function body, so we must + * use this function to detect that case when ending a function body. + * @param p The parser. + * @return True if we are in the top level of parsing a function body. + */ +static bool bc_parse_TopFunc(const BcParse *p) { + + bool good = p->flags.len == 2; + + uint16_t val = BC_PARSE_FLAG_BRACE | BC_PARSE_FLAG_FUNC_INNER; + val |= BC_PARSE_FLAG_FUNC; + + return good && BC_PARSE_TOP_FLAG(p) == val; +} + /** * Sets a previously defined exit label. What are labels? See the bc Parsing * section of the Development manual (manuals/development.md). * @param p The parser. */ static void bc_parse_setLabel(BcParse *p) { BcFunc *func = p->func; BcInstPtr *ip = bc_vec_top(&p->exits); size_t *label; assert(func == bc_vec_item(&p->prog->fns, p->fidx)); // Set the preallocated label to the correct index. label = bc_vec_item(&func->labels, ip->idx); *label = func->code.len; // Now, we don't need the exit label; it is done. bc_vec_pop(&p->exits); } /** * Creates a label and sets it to idx. If this is an exit label, then idx is * actually invalid, but it doesn't matter because it will be fixed by * bc_parse_setLabel() later. * @param p The parser. * @param idx The index of the label. */ static void bc_parse_createLabel(BcParse *p, size_t idx) { bc_vec_push(&p->func->labels, &idx); } /** * Creates a conditional label. Unlike an exit label, this label is set at * creation time because it comes *before* the code that will target it. * @param p The parser. * @param idx The index of the label. */ static void bc_parse_createCondLabel(BcParse *p, size_t idx) { bc_parse_createLabel(p, p->func->code.len); bc_vec_push(&p->conds, &idx); } /* * Creates an exit label to be filled in later by bc_parse_setLabel(). Also, why * create a label to be filled in later? Because exit labels are meant to be * targeted by code that comes *before* the label. Since we have to parse that * code first, and don't know how long it will be, we need to just make sure to * reserve a slot to be filled in later when we know. * * By the way, this uses BcInstPtr because it was convenient. The field idx * holds the index, and the field func holds the loop boolean. * * @param p The parser. * @param idx The index of the label's position. * @param loop True if the exit label is for a loop or not. */ static void bc_parse_createExitLabel(BcParse *p, size_t idx, bool loop) { BcInstPtr ip; assert(p->func == bc_vec_item(&p->prog->fns, p->fidx)); ip.func = loop; ip.idx = idx; ip.len = 0; bc_vec_push(&p->exits, &ip); bc_parse_createLabel(p, SIZE_MAX); } /** * Pops the correct operators off of the operator stack based on the current * operator. This is because of the Shunting-Yard algorithm. Lower prec means * higher precedence. * @param p The parser. * @param type The operator. * @param start The previous start of the operator stack. For more * information, see the bc Parsing section of the Development * manual (manuals/development.md). * @param nexprs A pointer to the current number of expressions that have not * been consumed yet. This is an IN and OUT parameter. */ static void bc_parse_operator(BcParse *p, BcLexType type, size_t start, size_t *nexprs) { BcLexType t; uchar l, r = BC_PARSE_OP_PREC(type); uchar left = BC_PARSE_OP_LEFT(type); // While we haven't hit the stop point yet. while (p->ops.len > start) { // Get the top operator. t = BC_PARSE_TOP_OP(p); // If it's a right paren, we have reached the end of whatever expression // this is no matter what. if (t == BC_LEX_LPAREN) break; // Break for precedence. Precedence operates differently on left and // right associativity, by the way. A left associative operator that // matches the current precedence should take priority, but a right // associative operator should not. l = BC_PARSE_OP_PREC(t); if (l >= r && (l != r || !left)) break; // Do the housekeeping. In particular, make sure to note that one // expression was consumed. (Two were, but another was added.) bc_parse_push(p, BC_PARSE_TOKEN_INST(t)); bc_vec_pop(&p->ops); *nexprs -= !BC_PARSE_OP_PREFIX(t); } bc_vec_push(&p->ops, &type); } /** * Parses a right paren. In the Shunting-Yard algorithm, it needs to be put on * the operator stack. But before that, it needs to consume whatever operators * there are until it hits a left paren. * @param p The parser. * @param nexprs A pointer to the current number of expressions that have not * been consumed yet. This is an IN and OUT parameter. */ static void bc_parse_rightParen(BcParse *p, size_t *nexprs) { BcLexType top; // Consume operators until a left paren. while ((top = BC_PARSE_TOP_OP(p)) != BC_LEX_LPAREN) { bc_parse_push(p, BC_PARSE_TOKEN_INST(top)); bc_vec_pop(&p->ops); *nexprs -= !BC_PARSE_OP_PREFIX(top); } // We need to pop the left paren as well. bc_vec_pop(&p->ops); // Oh, and we also want the next token. bc_lex_next(&p->l); } /** * Parses function arguments. * @param p The parser. * @param flags Flags restricting what kind of expressions the arguments can * be. */ static void bc_parse_args(BcParse *p, uint8_t flags) { bool comma = false; size_t nargs; bc_lex_next(&p->l); // Print and comparison operators not allowed. Well, comparison operators // only for POSIX. But we do allow arrays, and we *must* get a value. flags &= ~(BC_PARSE_PRINT | BC_PARSE_REL); flags |= (BC_PARSE_ARRAY | BC_PARSE_NEEDVAL); // Count the arguments and parse them. for (nargs = 0; p->l.t != BC_LEX_RPAREN; ++nargs) { bc_parse_expr_status(p, flags, bc_parse_next_arg); comma = (p->l.t == BC_LEX_COMMA); if (comma) bc_lex_next(&p->l); } // An ending comma is FAIL. if (BC_ERR(comma)) bc_parse_err(p, BC_ERR_PARSE_TOKEN); // Now do the call with the number of arguments. bc_parse_push(p, BC_INST_CALL); bc_parse_pushIndex(p, nargs); } /** * Parses a function call. * @param p The parser. * @param flags Flags restricting what kind of expressions the arguments can * be. */ static void bc_parse_call(BcParse *p, const char *name, uint8_t flags) { size_t idx; bc_parse_args(p, flags); // We just assert this because bc_parse_args() should // ensure that the next token is what it should be. assert(p->l.t == BC_LEX_RPAREN); // We cannot use bc_program_insertFunc() here // because it will overwrite an existing function. idx = bc_map_index(&p->prog->fn_map, name); // The function does not exist yet. Create a space for it. If the user does // not define it, it's a *runtime* error, not a parse error. if (idx == BC_VEC_INVALID_IDX) { - BC_SIG_LOCK; - idx = bc_program_insertFunc(p->prog, name); - BC_SIG_UNLOCK; - assert(idx != BC_VEC_INVALID_IDX); // Make sure that this pointer was not invalidated. p->func = bc_vec_item(&p->prog->fns, p->fidx); } // The function exists, so set the right function index. else idx = ((BcId*) bc_vec_item(&p->prog->fn_map, idx))->idx; bc_parse_pushIndex(p, idx); // Make sure to get the next token. bc_lex_next(&p->l); } /** * Parses a name/identifier-based expression. It could be a variable, an array * element, an array itself (for function arguments), a function call, etc. * */ static void bc_parse_name(BcParse *p, BcInst *type, bool *can_assign, uint8_t flags) { char *name; - BC_SIG_LOCK; + BC_SIG_ASSERT_LOCKED; // We want a copy of the name since the lexer might overwrite its copy. name = bc_vm_strdup(p->l.str.v); BC_SETJMP_LOCKED(err); - BC_SIG_UNLOCK; - // We need the next token to see if it's just a variable or something more. bc_lex_next(&p->l); // Array element or array. if (p->l.t == BC_LEX_LBRACKET) { bc_lex_next(&p->l); // Array only. This has to be a function parameter. if (p->l.t == BC_LEX_RBRACKET) { // Error if arrays are not allowed. if (BC_ERR(!(flags & BC_PARSE_ARRAY))) bc_parse_err(p, BC_ERR_PARSE_EXPR); *type = BC_INST_ARRAY; *can_assign = false; } else { // If we are here, we have an array element. We need to set the // expression parsing flags. uint8_t flags2 = (flags & ~(BC_PARSE_PRINT | BC_PARSE_REL)) | BC_PARSE_NEEDVAL; bc_parse_expr_status(p, flags2, bc_parse_next_elem); // The next token *must* be a right bracket. if (BC_ERR(p->l.t != BC_LEX_RBRACKET)) bc_parse_err(p, BC_ERR_PARSE_TOKEN); *type = BC_INST_ARRAY_ELEM; *can_assign = true; } // Make sure to get the next token. bc_lex_next(&p->l); // Push the instruction and the name of the identifier. bc_parse_push(p, *type); bc_parse_pushName(p, name, false); } else if (p->l.t == BC_LEX_LPAREN) { // We are parsing a function call; error if not allowed. if (BC_ERR(flags & BC_PARSE_NOCALL)) bc_parse_err(p, BC_ERR_PARSE_TOKEN); *type = BC_INST_CALL; *can_assign = false; bc_parse_call(p, name, flags); } else { // Just a variable. *type = BC_INST_VAR; *can_assign = true; bc_parse_push(p, BC_INST_VAR); bc_parse_pushName(p, name, true); } err: // Need to make sure to unallocate the name. - BC_SIG_MAYLOCK; free(name); BC_LONGJMP_CONT; + BC_SIG_MAYLOCK; } /** * Parses a builtin function that takes no arguments. This includes read(), * rand(), maxibase(), maxobase(), maxscale(), and maxrand(). * @param p The parser. * @param inst The instruction corresponding to the builtin. */ static void bc_parse_noArgBuiltin(BcParse *p, BcInst inst) { // Must have a left paren. bc_lex_next(&p->l); if (BC_ERR(p->l.t != BC_LEX_LPAREN)) bc_parse_err(p, BC_ERR_PARSE_TOKEN); // Must have a right paren. bc_lex_next(&p->l); if ((p->l.t != BC_LEX_RPAREN)) bc_parse_err(p, BC_ERR_PARSE_TOKEN); bc_parse_push(p, inst); bc_lex_next(&p->l); } /** * Parses a builtin function that takes 1 argument. This includes length(), * sqrt(), abs(), scale(), and irand(). * @param p The parser. * @param type The lex token. * @param flags The expression parsing flags for parsing the argument. * @param prev An out parameter; the previous instruction pointer. */ static void bc_parse_builtin(BcParse *p, BcLexType type, uint8_t flags, BcInst *prev) { // Must have a left paren. bc_lex_next(&p->l); if (BC_ERR(p->l.t != BC_LEX_LPAREN)) bc_parse_err(p, BC_ERR_PARSE_TOKEN); bc_lex_next(&p->l); // Change the flags as needed for parsing the argument. flags &= ~(BC_PARSE_PRINT | BC_PARSE_REL); flags |= BC_PARSE_NEEDVAL; // Since length can take arrays, we need to specially add that flag. if (type == BC_LEX_KW_LENGTH) flags |= BC_PARSE_ARRAY; bc_parse_expr_status(p, flags, bc_parse_next_rel); // Must have a right paren. if (BC_ERR(p->l.t != BC_LEX_RPAREN)) bc_parse_err(p, BC_ERR_PARSE_TOKEN); // Adjust previous based on the token and push it. *prev = type - BC_LEX_KW_LENGTH + BC_INST_LENGTH; bc_parse_push(p, *prev); bc_lex_next(&p->l); } /** * Parses a builtin function that takes 3 arguments. This includes modexp() and * divmod(). */ static void bc_parse_builtin3(BcParse *p, BcLexType type, uint8_t flags, BcInst *prev) { assert(type == BC_LEX_KW_MODEXP || type == BC_LEX_KW_DIVMOD); // Must have a left paren. bc_lex_next(&p->l); if (BC_ERR(p->l.t != BC_LEX_LPAREN)) bc_parse_err(p, BC_ERR_PARSE_TOKEN); bc_lex_next(&p->l); // Change the flags as needed for parsing the argument. flags &= ~(BC_PARSE_PRINT | BC_PARSE_REL); flags |= BC_PARSE_NEEDVAL; bc_parse_expr_status(p, flags, bc_parse_next_builtin); // Must have a comma. if (BC_ERR(p->l.t != BC_LEX_COMMA)) bc_parse_err(p, BC_ERR_PARSE_TOKEN); bc_lex_next(&p->l); bc_parse_expr_status(p, flags, bc_parse_next_builtin); // Must have a comma. if (BC_ERR(p->l.t != BC_LEX_COMMA)) bc_parse_err(p, BC_ERR_PARSE_TOKEN); bc_lex_next(&p->l); // If it is a divmod, parse an array name. Otherwise, just parse another // expression. if (type == BC_LEX_KW_DIVMOD) { // Must have a name. if (BC_ERR(p->l.t != BC_LEX_NAME)) bc_parse_err(p, BC_ERR_PARSE_TOKEN); // This is safe because the next token should not overwrite the name. bc_lex_next(&p->l); // Must have a left bracket. if (BC_ERR(p->l.t != BC_LEX_LBRACKET)) bc_parse_err(p, BC_ERR_PARSE_TOKEN); // This is safe because the next token should not overwrite the name. bc_lex_next(&p->l); // Must have a right bracket. if (BC_ERR(p->l.t != BC_LEX_RBRACKET)) bc_parse_err(p, BC_ERR_PARSE_TOKEN); // This is safe because the next token should not overwrite the name. bc_lex_next(&p->l); } else bc_parse_expr_status(p, flags, bc_parse_next_rel); // Must have a right paren. if (BC_ERR(p->l.t != BC_LEX_RPAREN)) bc_parse_err(p, BC_ERR_PARSE_TOKEN); // Adjust previous based on the token and push it. *prev = type - BC_LEX_KW_MODEXP + BC_INST_MODEXP; bc_parse_push(p, *prev); // If we have divmod, we need to assign the modulus to the array element, so // we need to push the instructions for doing so. if (type == BC_LEX_KW_DIVMOD) { // The zeroth element. bc_parse_push(p, BC_INST_ZERO); bc_parse_push(p, BC_INST_ARRAY_ELEM); // Push the array. bc_parse_pushName(p, p->l.str.v, false); // Swap them and assign. After this, the top item on the stack should // be the quotient. bc_parse_push(p, BC_INST_SWAP); bc_parse_push(p, BC_INST_ASSIGN_NO_VAL); } bc_lex_next(&p->l); } /** * Parses the scale keyword. This is special because scale can be a value or a * builtin function. * @param p The parser. * @param type An out parameter; the instruction for the parse. * @param can_assign An out parameter; whether the expression can be assigned * to. * @param flags The expression parsing flags for parsing a scale() arg. */ static void bc_parse_scale(BcParse *p, BcInst *type, bool *can_assign, uint8_t flags) { bc_lex_next(&p->l); // Without the left paren, it's just the keyword. if (p->l.t != BC_LEX_LPAREN) { // Set, push, and return. *type = BC_INST_SCALE; *can_assign = true; bc_parse_push(p, BC_INST_SCALE); return; } // Handle the scale function. *type = BC_INST_SCALE_FUNC; *can_assign = false; // Once again, adjust the flags. flags &= ~(BC_PARSE_PRINT | BC_PARSE_REL); flags |= BC_PARSE_NEEDVAL; bc_lex_next(&p->l); bc_parse_expr_status(p, flags, bc_parse_next_rel); // Must have a right paren. if (BC_ERR(p->l.t != BC_LEX_RPAREN)) bc_parse_err(p, BC_ERR_PARSE_TOKEN); bc_parse_push(p, BC_INST_SCALE_FUNC); bc_lex_next(&p->l); } /** * Parses and increment or decrement operator. This is a bit complex. * @param p The parser. * @param prev An out parameter; the previous instruction pointer. * @param can_assign An out parameter; whether the expression can be assigned * to. * @param nexs An in/out parameter; the number of expressions in the * parse tree that are not used. * @param flags The expression parsing flags for parsing a scale() arg. */ static void bc_parse_incdec(BcParse *p, BcInst *prev, bool *can_assign, size_t *nexs, uint8_t flags) { BcLexType type; uchar inst; BcInst etype = *prev; BcLexType last = p->l.last; assert(prev != NULL && can_assign != NULL); // If we can't assign to the previous token, then we have an error. if (BC_ERR(last == BC_LEX_OP_INC || last == BC_LEX_OP_DEC || last == BC_LEX_RPAREN)) { bc_parse_err(p, BC_ERR_PARSE_ASSIGN); } // Is the previous instruction for a variable? if (BC_PARSE_INST_VAR(etype)) { // If so, this is a postfix operator. if (!*can_assign) bc_parse_err(p, BC_ERR_PARSE_ASSIGN); // Only postfix uses BC_INST_INC and BC_INST_DEC. *prev = inst = BC_INST_INC + (p->l.t != BC_LEX_OP_INC); bc_parse_push(p, inst); bc_lex_next(&p->l); *can_assign = false; } else { // This is a prefix operator. In that case, we just convert it to // an assignment instruction. *prev = inst = BC_INST_ASSIGN_PLUS + (p->l.t != BC_LEX_OP_INC); bc_lex_next(&p->l); type = p->l.t; // Because we parse the next part of the expression // right here, we need to increment this. *nexs = *nexs + 1; // Is the next token a normal identifier? if (type == BC_LEX_NAME) { // Parse the name. uint8_t flags2 = flags & ~BC_PARSE_ARRAY; bc_parse_name(p, prev, can_assign, flags2 | BC_PARSE_NOCALL); } // Is the next token a global? else if (type >= BC_LEX_KW_LAST && type <= BC_LEX_KW_OBASE) { bc_parse_push(p, type - BC_LEX_KW_LAST + BC_INST_LAST); bc_lex_next(&p->l); } // Is the next token specifically scale, which needs special treatment? else if (BC_NO_ERR(type == BC_LEX_KW_SCALE)) { bc_lex_next(&p->l); // Check that scale() was not used. if (BC_ERR(p->l.t == BC_LEX_LPAREN)) bc_parse_err(p, BC_ERR_PARSE_TOKEN); else bc_parse_push(p, BC_INST_SCALE); } // Now we know we have an error. else bc_parse_err(p, BC_ERR_PARSE_TOKEN); *can_assign = false; bc_parse_push(p, BC_INST_ONE); bc_parse_push(p, inst); } } /** * Parses the minus operator. This needs special treatment because it is either * subtract or negation. * @param p The parser. * @param prev An in/out parameter; the previous instruction. * @param ops_bgn The size of the operator stack. * @param rparen True if the last token was a right paren. * @param binlast True if the last token was a binary operator. * @param nexprs An in/out parameter; the number of unused expressions. */ static void bc_parse_minus(BcParse *p, BcInst *prev, size_t ops_bgn, bool rparen, bool binlast, size_t *nexprs) { BcLexType type; bc_lex_next(&p->l); // Figure out if it's a minus or a negation. type = BC_PARSE_LEAF(*prev, binlast, rparen) ? BC_LEX_OP_MINUS : BC_LEX_NEG; *prev = BC_PARSE_TOKEN_INST(type); // We can just push onto the op stack because this is the largest // precedence operator that gets pushed. Inc/dec does not. if (type != BC_LEX_OP_MINUS) bc_vec_push(&p->ops, &type); else bc_parse_operator(p, type, ops_bgn, nexprs); } /** * Parses a string. * @param p The parser. * @param inst The instruction corresponding to how the string was found and * how it should be printed. */ static void bc_parse_str(BcParse *p, BcInst inst) { bc_parse_addString(p); bc_parse_push(p, inst); bc_lex_next(&p->l); } /** * Parses a print statement. * @param p The parser. */ static void bc_parse_print(BcParse *p, BcLexType type) { BcLexType t; bool comma = false; BcInst inst = type == BC_LEX_KW_STREAM ? BC_INST_PRINT_STREAM : BC_INST_PRINT_POP; bc_lex_next(&p->l); t = p->l.t; // A print or stream statement has to have *something*. if (bc_parse_isDelimiter(p)) bc_parse_err(p, BC_ERR_PARSE_PRINT); do { // If the token is a string, then print it with escapes. // BC_INST_PRINT_POP plays that role for bc. if (t == BC_LEX_STR) bc_parse_str(p, inst); else { // We have an actual number; parse and add a print instruction. bc_parse_expr_status(p, BC_PARSE_NEEDVAL, bc_parse_next_print); bc_parse_push(p, inst); } // Is the next token a comma? comma = (p->l.t == BC_LEX_COMMA); // Get the next token if we have a comma. if (comma) bc_lex_next(&p->l); else { // If we don't have a comma, the statement needs to end. if (!bc_parse_isDelimiter(p)) bc_parse_err(p, BC_ERR_PARSE_TOKEN); else break; } t = p->l.t; } while (true); // If we have a comma but no token, that's bad. if (BC_ERR(comma)) bc_parse_err(p, BC_ERR_PARSE_TOKEN); } /** * Parses a return statement. * @param p The parser. */ static void bc_parse_return(BcParse *p) { BcLexType t; bool paren; uchar inst = BC_INST_RET0; // If we are not in a function, that's an error. if (BC_ERR(!BC_PARSE_FUNC(p))) bc_parse_err(p, BC_ERR_PARSE_TOKEN); // If we are in a void function, make sure to return void. if (p->func->voidfn) inst = BC_INST_RET_VOID; bc_lex_next(&p->l); t = p->l.t; paren = (t == BC_LEX_LPAREN); // An empty return statement just needs to push the selected instruction. if (bc_parse_isDelimiter(p)) bc_parse_push(p, inst); else { BcParseStatus s; // Need to parse the expression whose value will be returned. s = bc_parse_expr_err(p, BC_PARSE_NEEDVAL, bc_parse_next_expr); // If the expression was empty, just push the selected instruction. if (s == BC_PARSE_STATUS_EMPTY_EXPR) { bc_parse_push(p, inst); bc_lex_next(&p->l); } // POSIX requires parentheses. if (!paren || p->l.last != BC_LEX_RPAREN) { bc_parse_err(p, BC_ERR_POSIX_RET); } // Void functions require an empty expression. if (BC_ERR(p->func->voidfn)) { if (s != BC_PARSE_STATUS_EMPTY_EXPR) bc_parse_verr(p, BC_ERR_PARSE_RET_VOID, p->func->name); } // If we got here, we want to be sure to end the function with a real // return instruction, just in case. else bc_parse_push(p, BC_INST_RET); } } /** * Clears flags that indicate the end of an if statement and its block and sets * the jump location. * @param p The parser. */ static void bc_parse_noElse(BcParse *p) { uint16_t *flag_ptr = BC_PARSE_TOP_FLAG_PTR(p); *flag_ptr = (*flag_ptr & ~(BC_PARSE_FLAG_IF_END)); bc_parse_setLabel(p); } /** * Ends (finishes parsing) the body of a control statement or a function. * @param p The parser. * @param brace True if the body was ended by a brace, false otherwise. */ static void bc_parse_endBody(BcParse *p, bool brace) { bool has_brace, new_else = false; // We cannot be ending a body if there are no bodies to end. if (BC_ERR(p->flags.len <= 1)) bc_parse_err(p, BC_ERR_PARSE_TOKEN); if (brace) { // The brace was already gotten; make sure that the caller did not lie. // We check for the requirement of braces later. assert(p->l.t == BC_LEX_RBRACE); bc_lex_next(&p->l); // If the next token is not a delimiter, that is a problem. - if (BC_ERR(!bc_parse_isDelimiter(p))) + if (BC_ERR(!bc_parse_isDelimiter(p) && !bc_parse_TopFunc(p))) bc_parse_err(p, BC_ERR_PARSE_TOKEN); } // Do we have a brace flag? has_brace = (BC_PARSE_BRACE(p) != 0); do { size_t len = p->flags.len; bool loop; // If we have a brace flag but not a brace, that's a problem. if (has_brace && !brace) bc_parse_err(p, BC_ERR_PARSE_TOKEN); // Are we inside a loop? loop = (BC_PARSE_LOOP_INNER(p) != 0); // If we are ending a loop or an else... if (loop || BC_PARSE_ELSE(p)) { // Loops have condition labels that we have to take care of as well. if (loop) { size_t *label = bc_vec_top(&p->conds); bc_parse_push(p, BC_INST_JUMP); bc_parse_pushIndex(p, *label); bc_vec_pop(&p->conds); } bc_parse_setLabel(p); bc_vec_pop(&p->flags); } // If we are ending a function... else if (BC_PARSE_FUNC_INNER(p)) { BcInst inst = (p->func->voidfn ? BC_INST_RET_VOID : BC_INST_RET0); bc_parse_push(p, inst); bc_parse_updateFunc(p, BC_PROG_MAIN); bc_vec_pop(&p->flags); } // If we have a brace flag and not an if statement, we can pop the top // of the flags stack because they have been taken care of above. else if (has_brace && !BC_PARSE_IF(p)) bc_vec_pop(&p->flags); // This needs to be last to parse nested if's properly. if (BC_PARSE_IF(p) && (len == p->flags.len || !BC_PARSE_BRACE(p))) { // Eat newlines. while (p->l.t == BC_LEX_NLINE) bc_lex_next(&p->l); // *Now* we can pop the flags. bc_vec_pop(&p->flags); // If we are allowed non-POSIX stuff... if (!BC_S) { // Have we found yet another dangling else? *(BC_PARSE_TOP_FLAG_PTR(p)) |= BC_PARSE_FLAG_IF_END; new_else = (p->l.t == BC_LEX_KW_ELSE); // Parse the else or end the if statement body. if (new_else) bc_parse_else(p); else if (!has_brace && (!BC_PARSE_IF_END(p) || brace)) bc_parse_noElse(p); } // POSIX requires us to do the bare minimum only. else bc_parse_noElse(p); } // If these are both true, we have "used" the braces that we found. if (brace && has_brace) brace = false; // This condition was perhaps the hardest single part of the parser. If the // flags stack does not have enough, we should stop. If we have a new else // statement, we should stop. If we do have the end of an if statement and // we have eaten the brace, we should stop. If we do have a brace flag, we // should stop. } while (p->flags.len > 1 && !new_else && (!BC_PARSE_IF_END(p) || brace) && !(has_brace = (BC_PARSE_BRACE(p) != 0))); // If we have a brace, yet no body for it, that's a problem. if (BC_ERR(p->flags.len == 1 && brace)) bc_parse_err(p, BC_ERR_PARSE_TOKEN); else if (brace && BC_PARSE_BRACE(p)) { // If we make it here, we have a brace and a flag for it. uint16_t flags = BC_PARSE_TOP_FLAG(p); // This condition ensure that the *last* body is correctly finished by // popping its flags. if (!(flags & (BC_PARSE_FLAG_FUNC_INNER | BC_PARSE_FLAG_LOOP_INNER)) && !(flags & (BC_PARSE_FLAG_IF | BC_PARSE_FLAG_ELSE)) && !(flags & (BC_PARSE_FLAG_IF_END))) { bc_vec_pop(&p->flags); } } } /** * Starts the body of a control statement or function. * @param p The parser. * @param flags The current flags (will be edited). */ static void bc_parse_startBody(BcParse *p, uint16_t flags) { assert(flags); flags |= (BC_PARSE_TOP_FLAG(p) & (BC_PARSE_FLAG_FUNC | BC_PARSE_FLAG_LOOP)); flags |= BC_PARSE_FLAG_BODY; bc_vec_push(&p->flags, &flags); } void bc_parse_endif(BcParse *p) { size_t i; bool good; // Not a problem if this is true. if (BC_NO_ERR(!BC_PARSE_NO_EXEC(p))) return; good = true; // Find an instance of a body that needs closing, i.e., a statement that did // not have a right brace when it should have. for (i = 0; good && i < p->flags.len; ++i) { uint16_t flag = *((uint16_t*) bc_vec_item(&p->flags, i)); good = ((flag & BC_PARSE_FLAG_BRACE) != BC_PARSE_FLAG_BRACE); } // If we did not find such an instance... if (good) { // We set this to restore it later. We don't want the parser thinking // that we are on stdin for this one because it will want more. bool is_stdin = vm.is_stdin; vm.is_stdin = false; // End all of the if statements and loops. while (p->flags.len > 1 || BC_PARSE_IF_END(p)) { if (BC_PARSE_IF_END(p)) bc_parse_noElse(p); if (p->flags.len > 1) bc_parse_endBody(p, false); } vm.is_stdin = is_stdin; } // If we reach here, a block was not properly closed, and we should error. else bc_parse_err(&vm.prs, BC_ERR_PARSE_BLOCK); } /** * Parses an if statement. * @param p The parser. */ static void bc_parse_if(BcParse *p) { // We are allowed relational operators, and we must have a value. size_t idx; uint8_t flags = (BC_PARSE_REL | BC_PARSE_NEEDVAL); // Get the left paren and barf if necessary. bc_lex_next(&p->l); if (BC_ERR(p->l.t != BC_LEX_LPAREN)) bc_parse_err(p, BC_ERR_PARSE_TOKEN); // Parse the condition. bc_lex_next(&p->l); bc_parse_expr_status(p, flags, bc_parse_next_rel); // Must have a right paren. if (BC_ERR(p->l.t != BC_LEX_RPAREN)) bc_parse_err(p, BC_ERR_PARSE_TOKEN); bc_lex_next(&p->l); // Insert the conditional jump instruction. bc_parse_push(p, BC_INST_JUMP_ZERO); idx = p->func->labels.len; // Push the index for the instruction and create an exit label for an else // statement. bc_parse_pushIndex(p, idx); bc_parse_createExitLabel(p, idx, false); bc_parse_startBody(p, BC_PARSE_FLAG_IF); } /** * Parses an else statement. * @param p The parser. */ static void bc_parse_else(BcParse *p) { size_t idx = p->func->labels.len; // We must be at the end of an if statement. if (BC_ERR(!BC_PARSE_IF_END(p))) bc_parse_err(p, BC_ERR_PARSE_TOKEN); // Push an unconditional jump to make bc jump over the else statement if it // executed the original if statement. bc_parse_push(p, BC_INST_JUMP); bc_parse_pushIndex(p, idx); // Clear the else stuff. Yes, that function is misnamed for its use here, // but deal with it. bc_parse_noElse(p); // Create the exit label and parse the body. bc_parse_createExitLabel(p, idx, false); bc_parse_startBody(p, BC_PARSE_FLAG_ELSE); bc_lex_next(&p->l); } /** * Parse a while loop. * @param p The parser. */ static void bc_parse_while(BcParse *p) { // We are allowed relational operators, and we must have a value. size_t idx; uint8_t flags = (BC_PARSE_REL | BC_PARSE_NEEDVAL); // Get the left paren and barf if necessary. bc_lex_next(&p->l); if (BC_ERR(p->l.t != BC_LEX_LPAREN)) bc_parse_err(p, BC_ERR_PARSE_TOKEN); bc_lex_next(&p->l); // Create the labels. Loops need both. bc_parse_createCondLabel(p, p->func->labels.len); idx = p->func->labels.len; bc_parse_createExitLabel(p, idx, true); // Parse the actual condition and barf on non-right paren. bc_parse_expr_status(p, flags, bc_parse_next_rel); if (BC_ERR(p->l.t != BC_LEX_RPAREN)) bc_parse_err(p, BC_ERR_PARSE_TOKEN); bc_lex_next(&p->l); // Now we can push the conditional jump and start the body. bc_parse_push(p, BC_INST_JUMP_ZERO); bc_parse_pushIndex(p, idx); bc_parse_startBody(p, BC_PARSE_FLAG_LOOP | BC_PARSE_FLAG_LOOP_INNER); } /** * Parse a for loop. * @param p The parser. */ static void bc_parse_for(BcParse *p) { size_t cond_idx, exit_idx, body_idx, update_idx; // Barf on the missing left paren. bc_lex_next(&p->l); if (BC_ERR(p->l.t != BC_LEX_LPAREN)) bc_parse_err(p, BC_ERR_PARSE_TOKEN); bc_lex_next(&p->l); // The first statement can be empty, but if it is, check for error in POSIX // mode. Otherwise, parse it. if (p->l.t != BC_LEX_SCOLON) bc_parse_expr_status(p, 0, bc_parse_next_for); else bc_parse_err(p, BC_ERR_POSIX_FOR); // Must have a semicolon. if (BC_ERR(p->l.t != BC_LEX_SCOLON)) bc_parse_err(p, BC_ERR_PARSE_TOKEN); bc_lex_next(&p->l); // These are indices for labels. There are so many of them because the end // of the loop must unconditionally jump to the update code. Then the update // code must unconditionally jump to the condition code. Then the condition // code must *conditionally* jump to the exit. cond_idx = p->func->labels.len; update_idx = cond_idx + 1; body_idx = update_idx + 1; exit_idx = body_idx + 1; // This creates the condition label. bc_parse_createLabel(p, p->func->code.len); // Parse an expression if it exists. if (p->l.t != BC_LEX_SCOLON) { uint8_t flags = (BC_PARSE_REL | BC_PARSE_NEEDVAL); bc_parse_expr_status(p, flags, bc_parse_next_for); } else { // Set this for the next call to bc_parse_number because an empty // condition means that it is an infinite loop, so the condition must be // non-zero. This is safe to set because the current token is a // semicolon, which has no string requirement. bc_vec_string(&p->l.str, sizeof(bc_parse_one) - 1, bc_parse_one); bc_parse_number(p); // An empty condition makes POSIX mad. bc_parse_err(p, BC_ERR_POSIX_FOR); } // Must have a semicolon. if (BC_ERR(p->l.t != BC_LEX_SCOLON)) bc_parse_err(p, BC_ERR_PARSE_TOKEN); bc_lex_next(&p->l); // Now we can set up the conditional jump to the exit and an unconditional // jump to the body right after. The unconditional jump to the body is // because there is update code coming right after the condition, so we need // to skip it to get to the body. bc_parse_push(p, BC_INST_JUMP_ZERO); bc_parse_pushIndex(p, exit_idx); bc_parse_push(p, BC_INST_JUMP); bc_parse_pushIndex(p, body_idx); // Now create the label for the update code. bc_parse_createCondLabel(p, update_idx); // Parse if not empty, and if it is, let POSIX yell if necessary. if (p->l.t != BC_LEX_RPAREN) bc_parse_expr_status(p, 0, bc_parse_next_rel); else bc_parse_err(p, BC_ERR_POSIX_FOR); // Must have a right paren. if (BC_ERR(p->l.t != BC_LEX_RPAREN)) bc_parse_err(p, BC_ERR_PARSE_TOKEN); // Set up a jump to the condition right after the update code. bc_parse_push(p, BC_INST_JUMP); bc_parse_pushIndex(p, cond_idx); bc_parse_createLabel(p, p->func->code.len); // Create an exit label for the body and start the body. bc_parse_createExitLabel(p, exit_idx, true); bc_lex_next(&p->l); bc_parse_startBody(p, BC_PARSE_FLAG_LOOP | BC_PARSE_FLAG_LOOP_INNER); } /** * Parse a statement or token that indicates a loop exit. This includes an * actual loop exit, the break keyword, or the continue keyword. * @param p The parser. * @param type The type of exit. */ static void bc_parse_loopExit(BcParse *p, BcLexType type) { size_t i; BcInstPtr *ip; // Must have a loop. If we don't, that's an error. if (BC_ERR(!BC_PARSE_LOOP(p))) bc_parse_err(p, BC_ERR_PARSE_TOKEN); // If we have a break statement... if (type == BC_LEX_KW_BREAK) { // If there are no exits, something went wrong somewhere. if (BC_ERR(!p->exits.len)) bc_parse_err(p, BC_ERR_PARSE_TOKEN); // Get the exit. i = p->exits.len - 1; ip = bc_vec_item(&p->exits, i); // The condition !ip->func is true if the exit is not for a loop, so we // need to find the first actual loop exit. while (!ip->func && i < p->exits.len) ip = bc_vec_item(&p->exits, i--); // Make sure everything is hunky dory. assert(ip != NULL && (i < p->exits.len || ip->func)); // Set the index for the exit. i = ip->idx; } // If we have a continue statement or just the loop end, jump to the // condition (or update for a foor loop). else i = *((size_t*) bc_vec_top(&p->conds)); // Add the unconditional jump. bc_parse_push(p, BC_INST_JUMP); bc_parse_pushIndex(p, i); bc_lex_next(&p->l); } /** * Parse a function (header). * @param p The parser. */ static void bc_parse_func(BcParse *p) { bool comma = false, voidfn; uint16_t flags; size_t idx; bc_lex_next(&p->l); // Must have a name. if (BC_ERR(p->l.t != BC_LEX_NAME)) bc_parse_err(p, BC_ERR_PARSE_FUNC); // If the name is "void", and POSIX is not on, mark as void. voidfn = (!BC_IS_POSIX && p->l.t == BC_LEX_NAME && !strcmp(p->l.str.v, "void")); // We can safely do this because the expected token should not overwrite the // function name. bc_lex_next(&p->l); // If we *don't* have another name, then void is the name of the function. voidfn = (voidfn && p->l.t == BC_LEX_NAME); // With a void function, allow POSIX to complain and get a new token. if (voidfn) { bc_parse_err(p, BC_ERR_POSIX_VOID); // We can safely do this because the expected token should not overwrite // the function name. bc_lex_next(&p->l); } // Must have a left paren. if (BC_ERR(p->l.t != BC_LEX_LPAREN)) bc_parse_err(p, BC_ERR_PARSE_FUNC); // Make sure the functions map and vector are synchronized. assert(p->prog->fns.len == p->prog->fn_map.len); - // Must lock signals because vectors are changed, and the vector functions - // expect signals to be locked. - BC_SIG_LOCK; - // Insert the function by name into the map and vector. idx = bc_program_insertFunc(p->prog, p->l.str.v); - BC_SIG_UNLOCK; - // Make sure the insert worked. assert(idx); // Update the function pointer and stuff in the parser and set its void. bc_parse_updateFunc(p, idx); p->func->voidfn = voidfn; bc_lex_next(&p->l); // While we do not have a right paren, we are still parsing arguments. while (p->l.t != BC_LEX_RPAREN) { BcType t = BC_TYPE_VAR; // If we have an asterisk, we are parsing a reference argument. if (p->l.t == BC_LEX_OP_MULTIPLY) { t = BC_TYPE_REF; bc_lex_next(&p->l); // Let POSIX complain if necessary. bc_parse_err(p, BC_ERR_POSIX_REF); } // If we don't have a name, the argument will not have a name. Barf. if (BC_ERR(p->l.t != BC_LEX_NAME)) bc_parse_err(p, BC_ERR_PARSE_FUNC); // Increment the number of parameters. p->func->nparams += 1; // Copy the string in the lexer so that we can use the lexer again. bc_vec_string(&p->buf, p->l.str.len, p->l.str.v); bc_lex_next(&p->l); // We are parsing an array parameter if this is true. if (p->l.t == BC_LEX_LBRACKET) { // Set the array type, unless we are already parsing a reference. if (t == BC_TYPE_VAR) t = BC_TYPE_ARRAY; bc_lex_next(&p->l); // The brackets *must* be empty. if (BC_ERR(p->l.t != BC_LEX_RBRACKET)) bc_parse_err(p, BC_ERR_PARSE_FUNC); bc_lex_next(&p->l); } // If we did *not* get a bracket, but we are expecting a reference, we // have a problem. else if (BC_ERR(t == BC_TYPE_REF)) bc_parse_verr(p, BC_ERR_PARSE_REF_VAR, p->buf.v); // Test for comma and get the next token if it exists. comma = (p->l.t == BC_LEX_COMMA); if (comma) bc_lex_next(&p->l); // Insert the parameter into the function. bc_func_insert(p->func, p->prog, p->buf.v, t, p->l.line); } // If we have a comma, but no parameter, barf. if (BC_ERR(comma)) bc_parse_err(p, BC_ERR_PARSE_FUNC); // Start the body. flags = BC_PARSE_FLAG_FUNC | BC_PARSE_FLAG_FUNC_INNER; bc_parse_startBody(p, flags); bc_lex_next(&p->l); // POSIX requires that a brace be on the same line as the function header. // If we don't have a brace, let POSIX throw an error. if (p->l.t != BC_LEX_LBRACE) bc_parse_err(p, BC_ERR_POSIX_BRACE); } /** * Parse an auto list. * @param p The parser. */ static void bc_parse_auto(BcParse *p) { bool comma, one; // Error if the auto keyword appeared in the wrong place. if (BC_ERR(!p->auto_part)) bc_parse_err(p, BC_ERR_PARSE_TOKEN); bc_lex_next(&p->l); p->auto_part = comma = false; // We need at least one variable or array. one = (p->l.t == BC_LEX_NAME); // While we have a variable or array. while (p->l.t == BC_LEX_NAME) { BcType t; // Copy the name from the lexer, so we can use it again. bc_vec_string(&p->buf, p->l.str.len - 1, p->l.str.v); bc_lex_next(&p->l); // If we are parsing an array... if (p->l.t == BC_LEX_LBRACKET) { t = BC_TYPE_ARRAY; bc_lex_next(&p->l); // The brackets *must* be empty. if (BC_ERR(p->l.t != BC_LEX_RBRACKET)) bc_parse_err(p, BC_ERR_PARSE_FUNC); bc_lex_next(&p->l); } else t = BC_TYPE_VAR; // Test for comma and get the next token if it exists. comma = (p->l.t == BC_LEX_COMMA); if (comma) bc_lex_next(&p->l); // Insert the auto into the function. bc_func_insert(p->func, p->prog, p->buf.v, t, p->l.line); } // If we have a comma, but no auto, barf. if (BC_ERR(comma)) bc_parse_err(p, BC_ERR_PARSE_FUNC); // If we don't have any variables or arrays, barf. if (BC_ERR(!one)) bc_parse_err(p, BC_ERR_PARSE_NO_AUTO); // The auto statement should be all that's in the statement. if (BC_ERR(!bc_parse_isDelimiter(p))) bc_parse_err(p, BC_ERR_PARSE_TOKEN); } /** * Parses a body. * @param p The parser. * @param brace True if a brace was encountered, false otherwise. */ static void bc_parse_body(BcParse *p, bool brace) { uint16_t *flag_ptr = BC_PARSE_TOP_FLAG_PTR(p); assert(flag_ptr != NULL); assert(p->flags.len >= 2); // The body flag is for when we expect a body. We got a body, so clear the // flag. *flag_ptr &= ~(BC_PARSE_FLAG_BODY); // If we are inside a function, that means we just barely entered it, and // we can expect an auto list. if (*flag_ptr & BC_PARSE_FLAG_FUNC_INNER) { // We *must* have a brace in this case. if (BC_ERR(!brace)) bc_parse_err(p, BC_ERR_PARSE_TOKEN); p->auto_part = (p->l.t != BC_LEX_KW_AUTO); if (!p->auto_part) { // Make sure this is true to not get a parse error. p->auto_part = true; // Since we already have the auto keyword, parse. bc_parse_auto(p); } // Eat a newline. if (p->l.t == BC_LEX_NLINE) bc_lex_next(&p->l); } else { // This is the easy part. size_t len = p->flags.len; assert(*flag_ptr); // Parse a statement. bc_parse_stmt(p); // This is a very important condition to get right. If there is no // brace, and no body flag, and the flags len hasn't shrunk, then we // have a body that was not delimited by braces, so we need to end it // now, after just one statement. if (!brace && !BC_PARSE_BODY(p) && len <= p->flags.len) bc_parse_endBody(p, false); } } /** * Parses a statement. This is the entry point for just about everything, except * function definitions. * @param p The parser. */ static void bc_parse_stmt(BcParse *p) { size_t len; uint16_t flags; BcLexType type = p->l.t; // Eat newline. if (type == BC_LEX_NLINE) { bc_lex_next(&p->l); return; } // Eat auto list. if (type == BC_LEX_KW_AUTO) { bc_parse_auto(p); return; } // If we reach this point, no auto list is allowed. p->auto_part = false; // Everything but an else needs to be taken care of here, but else is // special. if (type != BC_LEX_KW_ELSE) { // After an if, no else found. if (BC_PARSE_IF_END(p)) { // Clear the expectation for else, end body, and return. Returning // gives us a clean slate for parsing again. bc_parse_noElse(p); if (p->flags.len > 1 && !BC_PARSE_BRACE(p)) bc_parse_endBody(p, false); return; } // With a left brace, we are parsing a body. else if (type == BC_LEX_LBRACE) { // We need to start a body if we are not expecting one yet. if (!BC_PARSE_BODY(p)) { bc_parse_startBody(p, BC_PARSE_FLAG_BRACE); bc_lex_next(&p->l); } // If we *are* expecting a body, that body should get a brace. This // takes care of braces being on a different line than if and loop // headers. else { *(BC_PARSE_TOP_FLAG_PTR(p)) |= BC_PARSE_FLAG_BRACE; bc_lex_next(&p->l); bc_parse_body(p, true); } // If we have reached this point, we need to return for a clean // slate. return; } // This happens when we are expecting a body and get a single statement, // i.e., a body with no braces surrounding it. Returns after for a clean // slate. else if (BC_PARSE_BODY(p) && !BC_PARSE_BRACE(p)) { bc_parse_body(p, false); return; } } len = p->flags.len; flags = BC_PARSE_TOP_FLAG(p); switch (type) { // All of these are valid for expressions. case BC_LEX_OP_INC: case BC_LEX_OP_DEC: case BC_LEX_OP_MINUS: case BC_LEX_OP_BOOL_NOT: case BC_LEX_LPAREN: case BC_LEX_NAME: case BC_LEX_NUMBER: case BC_LEX_KW_IBASE: case BC_LEX_KW_LAST: case BC_LEX_KW_LENGTH: case BC_LEX_KW_OBASE: case BC_LEX_KW_SCALE: #if BC_ENABLE_EXTRA_MATH case BC_LEX_KW_SEED: #endif // BC_ENABLE_EXTRA_MATH case BC_LEX_KW_SQRT: case BC_LEX_KW_ABS: #if BC_ENABLE_EXTRA_MATH case BC_LEX_KW_IRAND: #endif // BC_ENABLE_EXTRA_MATH case BC_LEX_KW_ASCIIFY: case BC_LEX_KW_MODEXP: case BC_LEX_KW_DIVMOD: case BC_LEX_KW_READ: #if BC_ENABLE_EXTRA_MATH case BC_LEX_KW_RAND: #endif // BC_ENABLE_EXTRA_MATH case BC_LEX_KW_MAXIBASE: case BC_LEX_KW_MAXOBASE: case BC_LEX_KW_MAXSCALE: #if BC_ENABLE_EXTRA_MATH case BC_LEX_KW_MAXRAND: #endif // BC_ENABLE_EXTRA_MATH case BC_LEX_KW_LINE_LENGTH: case BC_LEX_KW_GLOBAL_STACKS: case BC_LEX_KW_LEADING_ZERO: { bc_parse_expr_status(p, BC_PARSE_PRINT, bc_parse_next_expr); break; } case BC_LEX_KW_ELSE: { bc_parse_else(p); break; } // Just eat. case BC_LEX_SCOLON: { // Do nothing. break; } case BC_LEX_RBRACE: { bc_parse_endBody(p, true); break; } case BC_LEX_STR: { bc_parse_str(p, BC_INST_PRINT_STR); break; } case BC_LEX_KW_BREAK: case BC_LEX_KW_CONTINUE: { bc_parse_loopExit(p, p->l.t); break; } case BC_LEX_KW_FOR: { bc_parse_for(p); break; } case BC_LEX_KW_HALT: { bc_parse_push(p, BC_INST_HALT); bc_lex_next(&p->l); break; } case BC_LEX_KW_IF: { bc_parse_if(p); break; } case BC_LEX_KW_LIMITS: { // `limits` is a compile-time command, so execute it right away. bc_vm_printf("BC_LONG_BIT = %lu\n", (ulong) BC_LONG_BIT); bc_vm_printf("BC_BASE_DIGS = %lu\n", (ulong) BC_BASE_DIGS); bc_vm_printf("BC_BASE_POW = %lu\n", (ulong) BC_BASE_POW); bc_vm_printf("BC_OVERFLOW_MAX = %lu\n", (ulong) BC_NUM_BIGDIG_MAX); bc_vm_printf("\n"); bc_vm_printf("BC_BASE_MAX = %lu\n", BC_MAX_OBASE); bc_vm_printf("BC_DIM_MAX = %lu\n", BC_MAX_DIM); bc_vm_printf("BC_SCALE_MAX = %lu\n", BC_MAX_SCALE); bc_vm_printf("BC_STRING_MAX = %lu\n", BC_MAX_STRING); bc_vm_printf("BC_NAME_MAX = %lu\n", BC_MAX_NAME); bc_vm_printf("BC_NUM_MAX = %lu\n", BC_MAX_NUM); #if BC_ENABLE_EXTRA_MATH bc_vm_printf("BC_RAND_MAX = %lu\n", BC_MAX_RAND); #endif // BC_ENABLE_EXTRA_MATH bc_vm_printf("MAX Exponent = %lu\n", BC_MAX_EXP); bc_vm_printf("Number of vars = %lu\n", BC_MAX_VARS); bc_lex_next(&p->l); break; } case BC_LEX_KW_STREAM: case BC_LEX_KW_PRINT: { bc_parse_print(p, type); break; } case BC_LEX_KW_QUIT: { // Quit is a compile-time command. We don't exit directly, so the vm // can clean up. vm.status = BC_STATUS_QUIT; BC_JMP; break; } case BC_LEX_KW_RETURN: { bc_parse_return(p); break; } case BC_LEX_KW_WHILE: { bc_parse_while(p); break; } default: { bc_parse_err(p, BC_ERR_PARSE_TOKEN); } } // If the flags did not change, we expect a delimiter. if (len == p->flags.len && flags == BC_PARSE_TOP_FLAG(p)) { if (BC_ERR(!bc_parse_isDelimiter(p))) bc_parse_err(p, BC_ERR_PARSE_TOKEN); } // Make sure semicolons are eaten. while (p->l.t == BC_LEX_SCOLON) bc_lex_next(&p->l); + + // POSIX's grammar does not allow a function definition after a semicolon + // without a newline, so check specifically for that case and error if + // the POSIX standard flag is set. + if (p->l.last == BC_LEX_SCOLON && p->l.t == BC_LEX_KW_DEFINE && BC_IS_POSIX) + { + bc_parse_err(p, BC_ERR_POSIX_FUNC_AFTER_SEMICOLON); + } } void bc_parse_parse(BcParse *p) { assert(p); - BC_SETJMP(exit); + BC_SETJMP_LOCKED(exit); // We should not let an EOF get here unless some partial parse was not // completed, in which case, it's the user's fault. if (BC_ERR(p->l.t == BC_LEX_EOF)) bc_parse_err(p, BC_ERR_PARSE_EOF); // Functions need special parsing. else if (p->l.t == BC_LEX_KW_DEFINE) { if (BC_ERR(BC_PARSE_NO_EXEC(p))) { bc_parse_endif(p); if (BC_ERR(BC_PARSE_NO_EXEC(p))) bc_parse_err(p, BC_ERR_PARSE_TOKEN); } bc_parse_func(p); } // Otherwise, parse a normal statement. else bc_parse_stmt(p); exit: - BC_SIG_MAYLOCK; - // We need to reset on error. if (BC_ERR(((vm.status && vm.status != BC_STATUS_QUIT) || vm.sig))) bc_parse_reset(p); BC_LONGJMP_CONT; + BC_SIG_MAYLOCK; } /** * Parse an expression. This is the actual implementation of the Shunting-Yard * Algorithm. * @param p The parser. * @param flags The flags for what is valid in the expression. * @param next A set of tokens for what is valid *after* the expression. * @return A parse status. In some places, an empty expression is an * error, and sometimes, it is required. This allows this function * to tell the caller if the expression was empty and let the * caller handle it. */ static BcParseStatus bc_parse_expr_err(BcParse *p, uint8_t flags, BcParseNext next) { BcInst prev = BC_INST_PRINT; uchar inst = BC_INST_INVALID; BcLexType top, t; size_t nexprs, ops_bgn; uint32_t i, nparens, nrelops; bool pfirst, rprn, done, get_token, assign, bin_last, incdec, can_assign; // One of these *must* be true. assert(!(flags & BC_PARSE_PRINT) || !(flags & BC_PARSE_NEEDVAL)); // These are set very carefully. In fact, controlling the values of these // locals is the biggest part of making this work. ops_bgn especially is // important because it marks where the operator stack begins for *this* // invocation of this function. That's because bc_parse_expr_err() is // recursive (the Shunting-Yard Algorithm is most easily expressed // recursively when parsing subexpressions), and each invocation needs to // know where to stop. // // - nparens is the number of left parens without matches. // - nrelops is the number of relational operators that appear in the expr. // - nexprs is the number of unused expressions. // - rprn is a right paren encountered last. // - done means the expression has been fully parsed. // - get_token is true when a token is needed at the end of an iteration. // - assign is true when an assignment statement was parsed last. // - incdec is true when the previous operator was an inc or dec operator. // - can_assign is true when an assignemnt is valid. // - bin_last is true when the previous instruction was a binary operator. t = p->l.t; pfirst = (p->l.t == BC_LEX_LPAREN); nparens = nrelops = 0; nexprs = 0; ops_bgn = p->ops.len; rprn = done = get_token = assign = incdec = can_assign = false; bin_last = true; // We want to eat newlines if newlines are not a valid ending token. // This is for spacing in things like for loop headers. if (!(flags & BC_PARSE_NOREAD)) { while ((t = p->l.t) == BC_LEX_NLINE) bc_lex_next(&p->l); } // This is the Shunting-Yard algorithm loop. for (; !done && BC_PARSE_EXPR(t); t = p->l.t) { switch (t) { case BC_LEX_OP_INC: case BC_LEX_OP_DEC: { // These operators can only be used with items that can be // assigned to. if (BC_ERR(incdec)) bc_parse_err(p, BC_ERR_PARSE_ASSIGN); bc_parse_incdec(p, &prev, &can_assign, &nexprs, flags); rprn = get_token = bin_last = false; incdec = true; flags &= ~(BC_PARSE_ARRAY); break; } #if BC_ENABLE_EXTRA_MATH case BC_LEX_OP_TRUNC: { // The previous token must have been a leaf expression, or the // operator is in the wrong place. if (BC_ERR(!BC_PARSE_LEAF(prev, bin_last, rprn))) bc_parse_err(p, BC_ERR_PARSE_TOKEN); // I can just add the instruction because // negative will already be taken care of. bc_parse_push(p, BC_INST_TRUNC); rprn = can_assign = incdec = false; get_token = true; flags &= ~(BC_PARSE_ARRAY); break; } #endif // BC_ENABLE_EXTRA_MATH case BC_LEX_OP_MINUS: { bc_parse_minus(p, &prev, ops_bgn, rprn, bin_last, &nexprs); rprn = get_token = can_assign = false; // This is true if it was a binary operator last. bin_last = (prev == BC_INST_MINUS); if (bin_last) incdec = false; flags &= ~(BC_PARSE_ARRAY); break; } // All of this group, including the fallthrough, is to parse binary // operators. case BC_LEX_OP_ASSIGN_POWER: case BC_LEX_OP_ASSIGN_MULTIPLY: case BC_LEX_OP_ASSIGN_DIVIDE: case BC_LEX_OP_ASSIGN_MODULUS: case BC_LEX_OP_ASSIGN_PLUS: case BC_LEX_OP_ASSIGN_MINUS: #if BC_ENABLE_EXTRA_MATH case BC_LEX_OP_ASSIGN_PLACES: case BC_LEX_OP_ASSIGN_LSHIFT: case BC_LEX_OP_ASSIGN_RSHIFT: #endif // BC_ENABLE_EXTRA_MATH case BC_LEX_OP_ASSIGN: { // We need to make sure the assignment is valid. if (!BC_PARSE_INST_VAR(prev)) bc_parse_err(p, BC_ERR_PARSE_ASSIGN); } // Fallthrough. BC_FALLTHROUGH case BC_LEX_OP_POWER: case BC_LEX_OP_MULTIPLY: case BC_LEX_OP_DIVIDE: case BC_LEX_OP_MODULUS: case BC_LEX_OP_PLUS: #if BC_ENABLE_EXTRA_MATH case BC_LEX_OP_PLACES: case BC_LEX_OP_LSHIFT: case BC_LEX_OP_RSHIFT: #endif // BC_ENABLE_EXTRA_MATH case BC_LEX_OP_REL_EQ: case BC_LEX_OP_REL_LE: case BC_LEX_OP_REL_GE: case BC_LEX_OP_REL_NE: case BC_LEX_OP_REL_LT: case BC_LEX_OP_REL_GT: case BC_LEX_OP_BOOL_NOT: case BC_LEX_OP_BOOL_OR: case BC_LEX_OP_BOOL_AND: { // This is true if the operator if the token is a prefix // operator. This is only for boolean not. if (BC_PARSE_OP_PREFIX(t)) { // Prefix operators are only allowed after binary operators // or prefix operators. if (BC_ERR(!bin_last && !BC_PARSE_OP_PREFIX(p->l.last))) bc_parse_err(p, BC_ERR_PARSE_EXPR); } // If we execute the else, that means we have a binary operator. // If the previous operator was a prefix or a binary operator, // then a binary operator is not allowed. else if (BC_ERR(BC_PARSE_PREV_PREFIX(prev) || bin_last)) bc_parse_err(p, BC_ERR_PARSE_EXPR); nrelops += (t >= BC_LEX_OP_REL_EQ && t <= BC_LEX_OP_REL_GT); prev = BC_PARSE_TOKEN_INST(t); bc_parse_operator(p, t, ops_bgn, &nexprs); rprn = incdec = can_assign = false; get_token = true; bin_last = !BC_PARSE_OP_PREFIX(t); flags &= ~(BC_PARSE_ARRAY); break; } case BC_LEX_LPAREN: { // A left paren is *not* allowed right after a leaf expr. if (BC_ERR(BC_PARSE_LEAF(prev, bin_last, rprn))) bc_parse_err(p, BC_ERR_PARSE_EXPR); nparens += 1; rprn = incdec = can_assign = false; get_token = true; // Push the paren onto the operator stack. bc_vec_push(&p->ops, &t); break; } case BC_LEX_RPAREN: { // This needs to be a status. The error is handled in // bc_parse_expr_status(). if (BC_ERR(p->l.last == BC_LEX_LPAREN)) return BC_PARSE_STATUS_EMPTY_EXPR; // The right paren must not come after a prefix or binary // operator. if (BC_ERR(bin_last || BC_PARSE_PREV_PREFIX(prev))) bc_parse_err(p, BC_ERR_PARSE_EXPR); // If there are no parens left, we are done, but we need another // token. if (!nparens) { done = true; get_token = false; break; } nparens -= 1; rprn = true; get_token = bin_last = incdec = false; bc_parse_rightParen(p, &nexprs); break; } case BC_LEX_STR: { // POSIX only allows strings alone. if (BC_IS_POSIX) bc_parse_err(p, BC_ERR_POSIX_EXPR_STRING); // A string is a leaf and cannot come right after a leaf. if (BC_ERR(BC_PARSE_LEAF(prev, bin_last, rprn))) bc_parse_err(p, BC_ERR_PARSE_EXPR); bc_parse_addString(p); get_token = true; bin_last = rprn = false; nexprs += 1; break; } case BC_LEX_NAME: { // A name is a leaf and cannot come right after a leaf. if (BC_ERR(BC_PARSE_LEAF(prev, bin_last, rprn))) bc_parse_err(p, BC_ERR_PARSE_EXPR); get_token = bin_last = false; bc_parse_name(p, &prev, &can_assign, flags & ~BC_PARSE_NOCALL); rprn = (prev == BC_INST_CALL); nexprs += 1; flags &= ~(BC_PARSE_ARRAY); break; } case BC_LEX_NUMBER: { // A number is a leaf and cannot come right after a leaf. if (BC_ERR(BC_PARSE_LEAF(prev, bin_last, rprn))) bc_parse_err(p, BC_ERR_PARSE_EXPR); // The number instruction is pushed in here. bc_parse_number(p); nexprs += 1; prev = BC_INST_NUM; get_token = true; rprn = bin_last = can_assign = false; flags &= ~(BC_PARSE_ARRAY); break; } case BC_LEX_KW_IBASE: case BC_LEX_KW_LAST: case BC_LEX_KW_OBASE: #if BC_ENABLE_EXTRA_MATH case BC_LEX_KW_SEED: #endif // BC_ENABLE_EXTRA_MATH { // All of these are leaves and cannot come right after a leaf. if (BC_ERR(BC_PARSE_LEAF(prev, bin_last, rprn))) bc_parse_err(p, BC_ERR_PARSE_EXPR); prev = t - BC_LEX_KW_LAST + BC_INST_LAST; bc_parse_push(p, prev); get_token = can_assign = true; rprn = bin_last = false; nexprs += 1; flags &= ~(BC_PARSE_ARRAY); break; } case BC_LEX_KW_LENGTH: case BC_LEX_KW_SQRT: case BC_LEX_KW_ABS: #if BC_ENABLE_EXTRA_MATH case BC_LEX_KW_IRAND: #endif // BC_ENABLE_EXTRA_MATH case BC_LEX_KW_ASCIIFY: { // All of these are leaves and cannot come right after a leaf. if (BC_ERR(BC_PARSE_LEAF(prev, bin_last, rprn))) bc_parse_err(p, BC_ERR_PARSE_EXPR); bc_parse_builtin(p, t, flags, &prev); rprn = get_token = bin_last = incdec = can_assign = false; nexprs += 1; flags &= ~(BC_PARSE_ARRAY); break; } case BC_LEX_KW_READ: #if BC_ENABLE_EXTRA_MATH case BC_LEX_KW_RAND: #endif // BC_ENABLE_EXTRA_MATH case BC_LEX_KW_MAXIBASE: case BC_LEX_KW_MAXOBASE: case BC_LEX_KW_MAXSCALE: #if BC_ENABLE_EXTRA_MATH case BC_LEX_KW_MAXRAND: #endif // BC_ENABLE_EXTRA_MATH case BC_LEX_KW_LINE_LENGTH: case BC_LEX_KW_GLOBAL_STACKS: case BC_LEX_KW_LEADING_ZERO: { // All of these are leaves and cannot come right after a leaf. if (BC_ERR(BC_PARSE_LEAF(prev, bin_last, rprn))) bc_parse_err(p, BC_ERR_PARSE_EXPR); // Error if we have read and it's not allowed. else if (t == BC_LEX_KW_READ && BC_ERR(flags & BC_PARSE_NOREAD)) bc_parse_err(p, BC_ERR_EXEC_REC_READ); prev = t - BC_LEX_KW_READ + BC_INST_READ; bc_parse_noArgBuiltin(p, prev); rprn = get_token = bin_last = incdec = can_assign = false; nexprs += 1; flags &= ~(BC_PARSE_ARRAY); break; } case BC_LEX_KW_SCALE: { // This is a leaf and cannot come right after a leaf. if (BC_ERR(BC_PARSE_LEAF(prev, bin_last, rprn))) bc_parse_err(p, BC_ERR_PARSE_EXPR); // Scale needs special work because it can be a variable *or* a // function. bc_parse_scale(p, &prev, &can_assign, flags); rprn = get_token = bin_last = false; nexprs += 1; flags &= ~(BC_PARSE_ARRAY); break; } case BC_LEX_KW_MODEXP: case BC_LEX_KW_DIVMOD: { // This is a leaf and cannot come right after a leaf. if (BC_ERR(BC_PARSE_LEAF(prev, bin_last, rprn))) bc_parse_err(p, BC_ERR_PARSE_EXPR); bc_parse_builtin3(p, t, flags, &prev); rprn = get_token = bin_last = incdec = can_assign = false; nexprs += 1; flags &= ~(BC_PARSE_ARRAY); break; } default: { #ifndef NDEBUG // We should never get here, even in debug builds. bc_parse_err(p, BC_ERR_PARSE_TOKEN); break; #endif // NDEBUG } } if (get_token) bc_lex_next(&p->l); } // Now that we have parsed the expression, we need to empty the operator // stack. while (p->ops.len > ops_bgn) { top = BC_PARSE_TOP_OP(p); assign = top >= BC_LEX_OP_ASSIGN_POWER && top <= BC_LEX_OP_ASSIGN; // There should not be *any* parens on the stack anymore. if (BC_ERR(top == BC_LEX_LPAREN || top == BC_LEX_RPAREN)) bc_parse_err(p, BC_ERR_PARSE_EXPR); bc_parse_push(p, BC_PARSE_TOKEN_INST(top)); // Adjust the number of unused expressions. nexprs -= !BC_PARSE_OP_PREFIX(top); bc_vec_pop(&p->ops); incdec = false; } // There must be only one expression at the top. if (BC_ERR(nexprs != 1)) bc_parse_err(p, BC_ERR_PARSE_EXPR); // Check that the next token is correct. for (i = 0; i < next.len && t != next.tokens[i]; ++i); if (BC_ERR(i == next.len && !bc_parse_isDelimiter(p))) bc_parse_err(p, BC_ERR_PARSE_EXPR); // Check that POSIX would be happy with the number of relational operators. if (!(flags & BC_PARSE_REL) && nrelops) bc_parse_err(p, BC_ERR_POSIX_REL_POS); else if ((flags & BC_PARSE_REL) && nrelops > 1) bc_parse_err(p, BC_ERR_POSIX_MULTIREL); // If this is true, then we might be in a situation where we don't print. // We would want to have the increment/decrement operator not make an extra // copy if it's not necessary. if (!(flags & BC_PARSE_NEEDVAL) && !pfirst) { // We have the easy case if the last operator was an assignment // operator. if (assign) { inst = *((uchar*) bc_vec_top(&p->func->code)); inst += (BC_INST_ASSIGN_POWER_NO_VAL - BC_INST_ASSIGN_POWER); incdec = false; } // If we have an inc/dec operator and we are *not* printing, implement // the optimization to get rid of the extra copy. else if (incdec && !(flags & BC_PARSE_PRINT)) { inst = *((uchar*) bc_vec_top(&p->func->code)); incdec = (inst <= BC_INST_DEC); inst = BC_INST_ASSIGN_PLUS_NO_VAL + (inst != BC_INST_INC && inst != BC_INST_ASSIGN_PLUS); } // This condition allows us to change the previous assignment // instruction (which does a copy) for a NO_VAL version, which does not. // This condition is set if either of the above if statements ends up // being true. if (inst >= BC_INST_ASSIGN_POWER_NO_VAL && inst <= BC_INST_ASSIGN_NO_VAL) { // Pop the previous assignment instruction and push a new one. // Inc/dec needs the extra instruction because it is now a binary // operator and needs a second operand. bc_vec_pop(&p->func->code); if (incdec) bc_parse_push(p, BC_INST_ONE); bc_parse_push(p, inst); } } // If we might have to print... if ((flags & BC_PARSE_PRINT)) { // With a paren first or the last operator not being an assignment, we // *do* want to print. if (pfirst || !assign) bc_parse_push(p, BC_INST_PRINT); } // We need to make sure to push a pop instruction for assignment statements // that will not print. The print will pop, but without it, we need to pop. else if (!(flags & BC_PARSE_NEEDVAL) && (inst < BC_INST_ASSIGN_POWER_NO_VAL || inst > BC_INST_ASSIGN_NO_VAL)) { bc_parse_push(p, BC_INST_POP); } // We want to eat newlines if newlines are not a valid ending token. // This is for spacing in things like for loop headers. // // Yes, this is one case where I reuse a variable for a different purpose; // in this case, incdec being true now means that newlines are not valid. for (incdec = true, i = 0; i < next.len && incdec; ++i) incdec = (next.tokens[i] != BC_LEX_NLINE); if (incdec) { while (p->l.t == BC_LEX_NLINE) bc_lex_next(&p->l); } return BC_PARSE_STATUS_SUCCESS; } /** * Parses an expression with bc_parse_expr_err(), but throws an error if it gets * an empty expression. * @param p The parser. * @param flags The flags for what is valid in the expression. * @param next A set of tokens for what is valid *after* the expression. */ static void bc_parse_expr_status(BcParse *p, uint8_t flags, BcParseNext next) { BcParseStatus s = bc_parse_expr_err(p, flags, next); if (BC_ERR(s == BC_PARSE_STATUS_EMPTY_EXPR)) bc_parse_err(p, BC_ERR_PARSE_EMPTY_EXPR); } void bc_parse_expr(BcParse *p, uint8_t flags) { assert(p); bc_parse_expr_status(p, flags, bc_parse_next_read); } #endif // BC_ENABLED diff --git a/contrib/bc/src/data.c b/contrib/bc/src/data.c index 82475299ed78..959af600c1af 100644 --- a/contrib/bc/src/data.c +++ b/contrib/bc/src/data.c @@ -1,1320 +1,1321 @@ /* * ***************************************************************************** * * SPDX-License-Identifier: BSD-2-Clause * * Copyright (c) 2018-2021 Gavin D. Howard and contributors. * * Redistribution and use in source and binary forms, with or without * modification, are permitted provided that the following conditions are met: * * * Redistributions of source code must retain the above copyright notice, this * list of conditions and the following disclaimer. * * * Redistributions in binary form must reproduce the above copyright notice, * this list of conditions and the following disclaimer in the documentation * and/or other materials provided with the distribution. * * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE * POSSIBILITY OF SUCH DAMAGE. * * ***************************************************************************** * * Constant data for bc. * */ #include #include #include #include #include #include #include #include #include #include #include #include #include #if !BC_ENABLE_LIBRARY #if BC_ENABLED /// The bc signal message and its length. const char bc_sig_msg[] = "\ninterrupt (type \"quit\" to exit)\n"; const uchar bc_sig_msg_len = (uchar) (sizeof(bc_sig_msg) - 1); #endif // BC_ENABLED #if DC_ENABLED /// The dc signal message and its length. const char dc_sig_msg[] = "\ninterrupt (type \"q\" to exit)\n"; const uchar dc_sig_msg_len = (uchar) (sizeof(dc_sig_msg) - 1); #endif // DC_ENABLED /// The copyright banner. const char bc_copyright[] = "Copyright (c) 2018-2021 Gavin D. Howard and contributors\n" "Report bugs at: https://git.yzena.com/gavin/bc\n\n" "This is free software with ABSOLUTELY NO WARRANTY.\n"; #ifdef __OpenBSD__ #if BC_ENABLE_EXTRA_MATH #if BC_ENABLE_HISTORY /// The pledges for starting bc. const char bc_pledge_start[] = "rpath stdio tty unveil"; /// The final pledges with history enabled. const char bc_pledge_end_history[] = "rpath stdio tty"; #else // BC_ENABLE_HISTORY /// The pledges for starting bc. const char bc_pledge_start[] = "rpath stdio unveil"; #endif // BC_ENABLE_HISTORY /// The final pledges with history history disabled. const char bc_pledge_end[] = "rpath stdio"; #else // BC_ENABLE_EXTRA_MATH #if BC_ENABLE_HISTORY /// The pledges for starting bc. const char bc_pledge_start[] = "rpath stdio tty"; /// The final pledges with history enabled. const char bc_pledge_end_history[] = "stdio tty"; #else // BC_ENABLE_HISTORY /// The pledges for starting bc. const char bc_pledge_start[] = "rpath stdio"; #endif // BC_ENABLE_HISTORY /// The final pledges with history history disabled. const char bc_pledge_end[] = "stdio"; #endif // BC_ENABLE_EXTRA_MATH #else // __OpenBSD__ /// The pledges for starting bc. const char bc_pledge_start[] = ""; #if BC_ENABLE_HISTORY /// The final pledges with history enabled. const char bc_pledge_end_history[] = ""; #endif // BC_ENABLE_HISTORY /// The final pledges with history history disabled. const char bc_pledge_end[] = ""; #endif // __OpenBSD__ /// The list of long options. There is a zero set at the end for detecting the /// end. const BcOptLong bc_args_lopt[] = { { "expression", BC_OPT_REQUIRED, 'e' }, { "file", BC_OPT_REQUIRED, 'f' }, { "help", BC_OPT_NONE, 'h' }, { "interactive", BC_OPT_NONE, 'i' }, { "leading-zeroes", BC_OPT_NONE, 'z' }, { "no-line-length", BC_OPT_NONE, 'L' }, { "no-prompt", BC_OPT_NONE, 'P' }, { "no-read-prompt", BC_OPT_NONE, 'R' }, #if BC_ENABLED { "global-stacks", BC_OPT_BC_ONLY, 'g' }, { "mathlib", BC_OPT_BC_ONLY, 'l' }, { "quiet", BC_OPT_BC_ONLY, 'q' }, { "redefine", BC_OPT_REQUIRED_BC_ONLY, 'r' }, { "standard", BC_OPT_BC_ONLY, 's' }, { "warn", BC_OPT_BC_ONLY, 'w' }, #endif // BC_ENABLED { "version", BC_OPT_NONE, 'v' }, { "version", BC_OPT_NONE, 'V' }, #if DC_ENABLED { "extended-register", BC_OPT_DC_ONLY, 'x' }, #endif // DC_ENABLED { NULL, 0, 0 }, }; /// The function header for error messages. const char* const bc_err_func_header = "Function:"; /// The line format string for error messages. const char* const bc_err_line = ":%zu"; /// The default error category strings. const char *bc_errs[] = { "Math error:", "Parse error:", "Runtime error:", "Fatal error:", #if BC_ENABLED "Warning:", #endif // BC_ENABLED }; /// The error category for each error. const uchar bc_err_ids[] = { BC_ERR_IDX_MATH, BC_ERR_IDX_MATH, BC_ERR_IDX_MATH, BC_ERR_IDX_MATH, BC_ERR_IDX_FATAL, BC_ERR_IDX_FATAL, BC_ERR_IDX_FATAL, BC_ERR_IDX_FATAL, BC_ERR_IDX_FATAL, BC_ERR_IDX_FATAL, BC_ERR_IDX_FATAL, BC_ERR_IDX_FATAL, BC_ERR_IDX_FATAL, BC_ERR_IDX_EXEC, BC_ERR_IDX_EXEC, BC_ERR_IDX_EXEC, BC_ERR_IDX_EXEC, BC_ERR_IDX_EXEC, BC_ERR_IDX_EXEC, BC_ERR_IDX_EXEC, BC_ERR_IDX_EXEC, BC_ERR_IDX_EXEC, BC_ERR_IDX_EXEC, BC_ERR_IDX_EXEC, BC_ERR_IDX_PARSE, BC_ERR_IDX_PARSE, BC_ERR_IDX_PARSE, BC_ERR_IDX_PARSE, BC_ERR_IDX_PARSE, #if BC_ENABLED BC_ERR_IDX_PARSE, BC_ERR_IDX_PARSE, BC_ERR_IDX_PARSE, BC_ERR_IDX_PARSE, BC_ERR_IDX_PARSE, BC_ERR_IDX_PARSE, BC_ERR_IDX_PARSE, BC_ERR_IDX_PARSE, BC_ERR_IDX_PARSE, BC_ERR_IDX_PARSE, BC_ERR_IDX_PARSE, BC_ERR_IDX_PARSE, BC_ERR_IDX_PARSE, BC_ERR_IDX_PARSE, BC_ERR_IDX_PARSE, BC_ERR_IDX_PARSE, BC_ERR_IDX_PARSE, BC_ERR_IDX_PARSE, BC_ERR_IDX_PARSE, BC_ERR_IDX_PARSE, BC_ERR_IDX_PARSE, BC_ERR_IDX_PARSE, - BC_ERR_IDX_PARSE, BC_ERR_IDX_PARSE, + BC_ERR_IDX_PARSE, BC_ERR_IDX_PARSE, BC_ERR_IDX_PARSE, #endif // BC_ENABLED }; /// The default error messages. There are NULL pointers because the positions /// must be preserved for the locales. const char* const bc_err_msgs[] = { "negative number", "non-integer number", "overflow: number cannot fit", "divide by 0", "memory allocation failed", "I/O error", "cannot open file: %s", "file is not text: %s", "path is a directory: %s", "bad command-line option: \"%s\"", "option requires an argument: '%c' (\"%s\")", "option takes no arguments: '%c' (\"%s\")", "bad option argument: \"%s\"", "bad ibase: must be [%lu, %lu]", "bad obase: must be [%lu, %lu]", "bad scale: must be [%lu, %lu]", "bad read() expression", "read() call inside of a read() call", "variable or array element is the wrong type", #if DC_ENABLED "stack has too few elements", "stack for register \"%s\" has too few elements", #else // DC_ENABLED NULL, NULL, #endif // DC_ENABLED #if BC_ENABLED "wrong number of parameters; need %zu, have %zu", "undefined function: %s()", "cannot use a void value in an expression", #else NULL, NULL, NULL, #endif // BC_ENABLED "end of file", "bad character '%c'", "string end cannot be found", "comment end cannot be found", "bad token", #if BC_ENABLED "bad expression", "empty expression", "bad print or stream statement", "bad function definition", ("bad assignment: left side must be scale, ibase, " "obase, seed, last, var, or array element"), "no auto variable found", "function parameter or auto \"%s%s\" already exists", "block end cannot be found", "cannot return a value from void function: %s()", "var cannot be a reference: %s", "POSIX does not allow names longer than 1 character: %s", "POSIX does not allow '#' script comments", "POSIX does not allow the following keyword: %s", "POSIX does not allow a period ('.') as a shortcut for the last result", "POSIX requires parentheses around return expressions", "POSIX does not allow the following operator: %s", "POSIX does not allow comparison operators outside if statements or loops", "POSIX requires 0 or 1 comparison operators per condition", "POSIX requires all 3 parts of a for loop to be non-empty", + "POSIX requires a newline between a semicolon and a function definition", #if BC_ENABLE_EXTRA_MATH "POSIX does not allow exponential notation", #else NULL, #endif // BC_ENABLE_EXTRA_MATH "POSIX does not allow array references as function parameters", "POSIX does not allow void functions", "POSIX requires the left brace be on the same line as the function header", "POSIX does not allow strings to be assigned to variables or arrays", #endif // BC_ENABLED }; #endif // !BC_ENABLE_LIBRARY /// The destructors corresponding to BcDtorType enum items. const BcVecFree bc_vec_dtors[] = { NULL, bc_vec_free, bc_num_free, #if !BC_ENABLE_LIBRARY #ifndef NDEBUG bc_func_free, #endif // NDEBUG bc_slab_free, bc_const_free, bc_result_free, #if BC_ENABLE_HISTORY bc_history_string_free, #endif // BC_ENABLE_HISTORY #else // !BC_ENABLE_LIBRARY bcl_num_destruct, #endif // !BC_ENABLE_LIBRARY }; #if !BC_ENABLE_LIBRARY #if BC_ENABLE_HISTORY /// A flush type for not clearing current extras but not saving new ones either. const BcFlushType bc_flush_none = BC_FLUSH_NO_EXTRAS_NO_CLEAR; /// A flush type for clearing extras and not saving new ones. const BcFlushType bc_flush_err = BC_FLUSH_NO_EXTRAS_CLEAR; /// A flush type for clearing previous extras and saving new ones. const BcFlushType bc_flush_save = BC_FLUSH_SAVE_EXTRAS_CLEAR; #endif // BC_ENABLE_HISTORY #if BC_ENABLE_HISTORY /// A list of known bad terminals. const char *bc_history_bad_terms[] = { "dumb", "cons25", "emacs", NULL }; /// A constant for tabs and its length. My tab handling is dumb and always /// outputs the entire thing. const char bc_history_tab[] = " "; const size_t bc_history_tab_len = sizeof(bc_history_tab) - 1; /// A list of wide chars. These are listed in ascending order for efficiency. const uint32_t bc_history_wchars[][2] = { { 0x1100, 0x115F }, { 0x231A, 0x231B }, { 0x2329, 0x232A }, { 0x23E9, 0x23EC }, { 0x23F0, 0x23F0 }, { 0x23F3, 0x23F3 }, { 0x25FD, 0x25FE }, { 0x2614, 0x2615 }, { 0x2648, 0x2653 }, { 0x267F, 0x267F }, { 0x2693, 0x2693 }, { 0x26A1, 0x26A1 }, { 0x26AA, 0x26AB }, { 0x26BD, 0x26BE }, { 0x26C4, 0x26C5 }, { 0x26CE, 0x26CE }, { 0x26D4, 0x26D4 }, { 0x26EA, 0x26EA }, { 0x26F2, 0x26F3 }, { 0x26F5, 0x26F5 }, { 0x26FA, 0x26FA }, { 0x26FD, 0x26FD }, { 0x2705, 0x2705 }, { 0x270A, 0x270B }, { 0x2728, 0x2728 }, { 0x274C, 0x274C }, { 0x274E, 0x274E }, { 0x2753, 0x2755 }, { 0x2757, 0x2757 }, { 0x2795, 0x2797 }, { 0x27B0, 0x27B0 }, { 0x27BF, 0x27BF }, { 0x2B1B, 0x2B1C }, { 0x2B50, 0x2B50 }, { 0x2B55, 0x2B55 }, { 0x2E80, 0x2E99 }, { 0x2E9B, 0x2EF3 }, { 0x2F00, 0x2FD5 }, { 0x2FF0, 0x2FFB }, { 0x3001, 0x303E }, { 0x3041, 0x3096 }, { 0x3099, 0x30FF }, { 0x3105, 0x312D }, { 0x3131, 0x318E }, { 0x3190, 0x31BA }, { 0x31C0, 0x31E3 }, { 0x31F0, 0x321E }, { 0x3220, 0x3247 }, { 0x3250, 0x32FE }, { 0x3300, 0x4DBF }, { 0x4E00, 0xA48C }, { 0xA490, 0xA4C6 }, { 0xA960, 0xA97C }, { 0xAC00, 0xD7A3 }, { 0xF900, 0xFAFF }, { 0xFE10, 0xFE19 }, { 0xFE30, 0xFE52 }, { 0xFE54, 0xFE66 }, { 0xFE68, 0xFE6B }, { 0x16FE0, 0x16FE0 }, { 0x17000, 0x187EC }, { 0x18800, 0x18AF2 }, { 0x1B000, 0x1B001 }, { 0x1F004, 0x1F004 }, { 0x1F0CF, 0x1F0CF }, { 0x1F18E, 0x1F18E }, { 0x1F191, 0x1F19A }, { 0x1F200, 0x1F202 }, { 0x1F210, 0x1F23B }, { 0x1F240, 0x1F248 }, { 0x1F250, 0x1F251 }, { 0x1F300, 0x1F320 }, { 0x1F32D, 0x1F335 }, { 0x1F337, 0x1F37C }, { 0x1F37E, 0x1F393 }, { 0x1F3A0, 0x1F3CA }, { 0x1F3CF, 0x1F3D3 }, { 0x1F3E0, 0x1F3F0 }, { 0x1F3F4, 0x1F3F4 }, { 0x1F3F8, 0x1F43E }, { 0x1F440, 0x1F440 }, { 0x1F442, 0x1F4FC }, { 0x1F4FF, 0x1F53D }, { 0x1F54B, 0x1F54E }, { 0x1F550, 0x1F567 }, { 0x1F57A, 0x1F57A }, { 0x1F595, 0x1F596 }, { 0x1F5A4, 0x1F5A4 }, { 0x1F5FB, 0x1F64F }, { 0x1F680, 0x1F6C5 }, { 0x1F6CC, 0x1F6CC }, { 0x1F6D0, 0x1F6D2 }, { 0x1F6EB, 0x1F6EC }, { 0x1F6F4, 0x1F6F6 }, { 0x1F910, 0x1F91E }, { 0x1F920, 0x1F927 }, { 0x1F930, 0x1F930 }, { 0x1F933, 0x1F93E }, { 0x1F940, 0x1F94B }, { 0x1F950, 0x1F95E }, { 0x1F980, 0x1F991 }, { 0x1F9C0, 0x1F9C0 }, { 0x20000, 0x2FFFD }, { 0x30000, 0x3FFFD }, }; /// The length of the wide chars list. const size_t bc_history_wchars_len = sizeof(bc_history_wchars) / sizeof(bc_history_wchars[0]); /// A list of combining characters in Unicode. These are listed in ascending /// order for efficiency. const uint32_t bc_history_combo_chars[] = { 0x0300,0x0301,0x0302,0x0303,0x0304,0x0305,0x0306,0x0307, 0x0308,0x0309,0x030A,0x030B,0x030C,0x030D,0x030E,0x030F, 0x0310,0x0311,0x0312,0x0313,0x0314,0x0315,0x0316,0x0317, 0x0318,0x0319,0x031A,0x031B,0x031C,0x031D,0x031E,0x031F, 0x0320,0x0321,0x0322,0x0323,0x0324,0x0325,0x0326,0x0327, 0x0328,0x0329,0x032A,0x032B,0x032C,0x032D,0x032E,0x032F, 0x0330,0x0331,0x0332,0x0333,0x0334,0x0335,0x0336,0x0337, 0x0338,0x0339,0x033A,0x033B,0x033C,0x033D,0x033E,0x033F, 0x0340,0x0341,0x0342,0x0343,0x0344,0x0345,0x0346,0x0347, 0x0348,0x0349,0x034A,0x034B,0x034C,0x034D,0x034E,0x034F, 0x0350,0x0351,0x0352,0x0353,0x0354,0x0355,0x0356,0x0357, 0x0358,0x0359,0x035A,0x035B,0x035C,0x035D,0x035E,0x035F, 0x0360,0x0361,0x0362,0x0363,0x0364,0x0365,0x0366,0x0367, 0x0368,0x0369,0x036A,0x036B,0x036C,0x036D,0x036E,0x036F, 0x0483,0x0484,0x0485,0x0486,0x0487,0x0591,0x0592,0x0593, 0x0594,0x0595,0x0596,0x0597,0x0598,0x0599,0x059A,0x059B, 0x059C,0x059D,0x059E,0x059F,0x05A0,0x05A1,0x05A2,0x05A3, 0x05A4,0x05A5,0x05A6,0x05A7,0x05A8,0x05A9,0x05AA,0x05AB, 0x05AC,0x05AD,0x05AE,0x05AF,0x05B0,0x05B1,0x05B2,0x05B3, 0x05B4,0x05B5,0x05B6,0x05B7,0x05B8,0x05B9,0x05BA,0x05BB, 0x05BC,0x05BD,0x05BF,0x05C1,0x05C2,0x05C4,0x05C5,0x05C7, 0x0610,0x0611,0x0612,0x0613,0x0614,0x0615,0x0616,0x0617, 0x0618,0x0619,0x061A,0x064B,0x064C,0x064D,0x064E,0x064F, 0x0650,0x0651,0x0652,0x0653,0x0654,0x0655,0x0656,0x0657, 0x0658,0x0659,0x065A,0x065B,0x065C,0x065D,0x065E,0x065F, 0x0670,0x06D6,0x06D7,0x06D8,0x06D9,0x06DA,0x06DB,0x06DC, 0x06DF,0x06E0,0x06E1,0x06E2,0x06E3,0x06E4,0x06E7,0x06E8, 0x06EA,0x06EB,0x06EC,0x06ED,0x0711,0x0730,0x0731,0x0732, 0x0733,0x0734,0x0735,0x0736,0x0737,0x0738,0x0739,0x073A, 0x073B,0x073C,0x073D,0x073E,0x073F,0x0740,0x0741,0x0742, 0x0743,0x0744,0x0745,0x0746,0x0747,0x0748,0x0749,0x074A, 0x07A6,0x07A7,0x07A8,0x07A9,0x07AA,0x07AB,0x07AC,0x07AD, 0x07AE,0x07AF,0x07B0,0x07EB,0x07EC,0x07ED,0x07EE,0x07EF, 0x07F0,0x07F1,0x07F2,0x07F3,0x0816,0x0817,0x0818,0x0819, 0x081B,0x081C,0x081D,0x081E,0x081F,0x0820,0x0821,0x0822, 0x0823,0x0825,0x0826,0x0827,0x0829,0x082A,0x082B,0x082C, 0x082D,0x0859,0x085A,0x085B,0x08D4,0x08D5,0x08D6,0x08D7, 0x08D8,0x08D9,0x08DA,0x08DB,0x08DC,0x08DD,0x08DE,0x08DF, 0x08E0,0x08E1,0x08E3,0x08E4,0x08E5,0x08E6,0x08E7,0x08E8, 0x08E9,0x08EA,0x08EB,0x08EC,0x08ED,0x08EE,0x08EF,0x08F0, 0x08F1,0x08F2,0x08F3,0x08F4,0x08F5,0x08F6,0x08F7,0x08F8, 0x08F9,0x08FA,0x08FB,0x08FC,0x08FD,0x08FE,0x08FF,0x0900, 0x0901,0x0902,0x093A,0x093C,0x0941,0x0942,0x0943,0x0944, 0x0945,0x0946,0x0947,0x0948,0x094D,0x0951,0x0952,0x0953, 0x0954,0x0955,0x0956,0x0957,0x0962,0x0963,0x0981,0x09BC, 0x09C1,0x09C2,0x09C3,0x09C4,0x09CD,0x09E2,0x09E3,0x0A01, 0x0A02,0x0A3C,0x0A41,0x0A42,0x0A47,0x0A48,0x0A4B,0x0A4C, 0x0A4D,0x0A51,0x0A70,0x0A71,0x0A75,0x0A81,0x0A82,0x0ABC, 0x0AC1,0x0AC2,0x0AC3,0x0AC4,0x0AC5,0x0AC7,0x0AC8,0x0ACD, 0x0AE2,0x0AE3,0x0B01,0x0B3C,0x0B3F,0x0B41,0x0B42,0x0B43, 0x0B44,0x0B4D,0x0B56,0x0B62,0x0B63,0x0B82,0x0BC0,0x0BCD, 0x0C00,0x0C3E,0x0C3F,0x0C40,0x0C46,0x0C47,0x0C48,0x0C4A, 0x0C4B,0x0C4C,0x0C4D,0x0C55,0x0C56,0x0C62,0x0C63,0x0C81, 0x0CBC,0x0CBF,0x0CC6,0x0CCC,0x0CCD,0x0CE2,0x0CE3,0x0D01, 0x0D41,0x0D42,0x0D43,0x0D44,0x0D4D,0x0D62,0x0D63,0x0DCA, 0x0DD2,0x0DD3,0x0DD4,0x0DD6,0x0E31,0x0E34,0x0E35,0x0E36, 0x0E37,0x0E38,0x0E39,0x0E3A,0x0E47,0x0E48,0x0E49,0x0E4A, 0x0E4B,0x0E4C,0x0E4D,0x0E4E,0x0EB1,0x0EB4,0x0EB5,0x0EB6, 0x0EB7,0x0EB8,0x0EB9,0x0EBB,0x0EBC,0x0EC8,0x0EC9,0x0ECA, 0x0ECB,0x0ECC,0x0ECD,0x0F18,0x0F19,0x0F35,0x0F37,0x0F39, 0x0F71,0x0F72,0x0F73,0x0F74,0x0F75,0x0F76,0x0F77,0x0F78, 0x0F79,0x0F7A,0x0F7B,0x0F7C,0x0F7D,0x0F7E,0x0F80,0x0F81, 0x0F82,0x0F83,0x0F84,0x0F86,0x0F87,0x0F8D,0x0F8E,0x0F8F, 0x0F90,0x0F91,0x0F92,0x0F93,0x0F94,0x0F95,0x0F96,0x0F97, 0x0F99,0x0F9A,0x0F9B,0x0F9C,0x0F9D,0x0F9E,0x0F9F,0x0FA0, 0x0FA1,0x0FA2,0x0FA3,0x0FA4,0x0FA5,0x0FA6,0x0FA7,0x0FA8, 0x0FA9,0x0FAA,0x0FAB,0x0FAC,0x0FAD,0x0FAE,0x0FAF,0x0FB0, 0x0FB1,0x0FB2,0x0FB3,0x0FB4,0x0FB5,0x0FB6,0x0FB7,0x0FB8, 0x0FB9,0x0FBA,0x0FBB,0x0FBC,0x0FC6,0x102D,0x102E,0x102F, 0x1030,0x1032,0x1033,0x1034,0x1035,0x1036,0x1037,0x1039, 0x103A,0x103D,0x103E,0x1058,0x1059,0x105E,0x105F,0x1060, 0x1071,0x1072,0x1073,0x1074,0x1082,0x1085,0x1086,0x108D, 0x109D,0x135D,0x135E,0x135F,0x1712,0x1713,0x1714,0x1732, 0x1733,0x1734,0x1752,0x1753,0x1772,0x1773,0x17B4,0x17B5, 0x17B7,0x17B8,0x17B9,0x17BA,0x17BB,0x17BC,0x17BD,0x17C6, 0x17C9,0x17CA,0x17CB,0x17CC,0x17CD,0x17CE,0x17CF,0x17D0, 0x17D1,0x17D2,0x17D3,0x17DD,0x180B,0x180C,0x180D,0x1885, 0x1886,0x18A9,0x1920,0x1921,0x1922,0x1927,0x1928,0x1932, 0x1939,0x193A,0x193B,0x1A17,0x1A18,0x1A1B,0x1A56,0x1A58, 0x1A59,0x1A5A,0x1A5B,0x1A5C,0x1A5D,0x1A5E,0x1A60,0x1A62, 0x1A65,0x1A66,0x1A67,0x1A68,0x1A69,0x1A6A,0x1A6B,0x1A6C, 0x1A73,0x1A74,0x1A75,0x1A76,0x1A77,0x1A78,0x1A79,0x1A7A, 0x1A7B,0x1A7C,0x1A7F,0x1AB0,0x1AB1,0x1AB2,0x1AB3,0x1AB4, 0x1AB5,0x1AB6,0x1AB7,0x1AB8,0x1AB9,0x1ABA,0x1ABB,0x1ABC, 0x1ABD,0x1B00,0x1B01,0x1B02,0x1B03,0x1B34,0x1B36,0x1B37, 0x1B38,0x1B39,0x1B3A,0x1B3C,0x1B42,0x1B6B,0x1B6C,0x1B6D, 0x1B6E,0x1B6F,0x1B70,0x1B71,0x1B72,0x1B73,0x1B80,0x1B81, 0x1BA2,0x1BA3,0x1BA4,0x1BA5,0x1BA8,0x1BA9,0x1BAB,0x1BAC, 0x1BAD,0x1BE6,0x1BE8,0x1BE9,0x1BED,0x1BEF,0x1BF0,0x1BF1, 0x1C2C,0x1C2D,0x1C2E,0x1C2F,0x1C30,0x1C31,0x1C32,0x1C33, 0x1C36,0x1C37,0x1CD0,0x1CD1,0x1CD2,0x1CD4,0x1CD5,0x1CD6, 0x1CD7,0x1CD8,0x1CD9,0x1CDA,0x1CDB,0x1CDC,0x1CDD,0x1CDE, 0x1CDF,0x1CE0,0x1CE2,0x1CE3,0x1CE4,0x1CE5,0x1CE6,0x1CE7, 0x1CE8,0x1CED,0x1CF4,0x1CF8,0x1CF9,0x1DC0,0x1DC1,0x1DC2, 0x1DC3,0x1DC4,0x1DC5,0x1DC6,0x1DC7,0x1DC8,0x1DC9,0x1DCA, 0x1DCB,0x1DCC,0x1DCD,0x1DCE,0x1DCF,0x1DD0,0x1DD1,0x1DD2, 0x1DD3,0x1DD4,0x1DD5,0x1DD6,0x1DD7,0x1DD8,0x1DD9,0x1DDA, 0x1DDB,0x1DDC,0x1DDD,0x1DDE,0x1DDF,0x1DE0,0x1DE1,0x1DE2, 0x1DE3,0x1DE4,0x1DE5,0x1DE6,0x1DE7,0x1DE8,0x1DE9,0x1DEA, 0x1DEB,0x1DEC,0x1DED,0x1DEE,0x1DEF,0x1DF0,0x1DF1,0x1DF2, 0x1DF3,0x1DF4,0x1DF5,0x1DFB,0x1DFC,0x1DFD,0x1DFE,0x1DFF, 0x20D0,0x20D1,0x20D2,0x20D3,0x20D4,0x20D5,0x20D6,0x20D7, 0x20D8,0x20D9,0x20DA,0x20DB,0x20DC,0x20E1,0x20E5,0x20E6, 0x20E7,0x20E8,0x20E9,0x20EA,0x20EB,0x20EC,0x20ED,0x20EE, 0x20EF,0x20F0,0x2CEF,0x2CF0,0x2CF1,0x2D7F,0x2DE0,0x2DE1, 0x2DE2,0x2DE3,0x2DE4,0x2DE5,0x2DE6,0x2DE7,0x2DE8,0x2DE9, 0x2DEA,0x2DEB,0x2DEC,0x2DED,0x2DEE,0x2DEF,0x2DF0,0x2DF1, 0x2DF2,0x2DF3,0x2DF4,0x2DF5,0x2DF6,0x2DF7,0x2DF8,0x2DF9, 0x2DFA,0x2DFB,0x2DFC,0x2DFD,0x2DFE,0x2DFF,0x302A,0x302B, 0x302C,0x302D,0x3099,0x309A,0xA66F,0xA674,0xA675,0xA676, 0xA677,0xA678,0xA679,0xA67A,0xA67B,0xA67C,0xA67D,0xA69E, 0xA69F,0xA6F0,0xA6F1,0xA802,0xA806,0xA80B,0xA825,0xA826, 0xA8C4,0xA8C5,0xA8E0,0xA8E1,0xA8E2,0xA8E3,0xA8E4,0xA8E5, 0xA8E6,0xA8E7,0xA8E8,0xA8E9,0xA8EA,0xA8EB,0xA8EC,0xA8ED, 0xA8EE,0xA8EF,0xA8F0,0xA8F1,0xA926,0xA927,0xA928,0xA929, 0xA92A,0xA92B,0xA92C,0xA92D,0xA947,0xA948,0xA949,0xA94A, 0xA94B,0xA94C,0xA94D,0xA94E,0xA94F,0xA950,0xA951,0xA980, 0xA981,0xA982,0xA9B3,0xA9B6,0xA9B7,0xA9B8,0xA9B9,0xA9BC, 0xA9E5,0xAA29,0xAA2A,0xAA2B,0xAA2C,0xAA2D,0xAA2E,0xAA31, 0xAA32,0xAA35,0xAA36,0xAA43,0xAA4C,0xAA7C,0xAAB0,0xAAB2, 0xAAB3,0xAAB4,0xAAB7,0xAAB8,0xAABE,0xAABF,0xAAC1,0xAAEC, 0xAAED,0xAAF6,0xABE5,0xABE8,0xABED,0xFB1E,0xFE00,0xFE01, 0xFE02,0xFE03,0xFE04,0xFE05,0xFE06,0xFE07,0xFE08,0xFE09, 0xFE0A,0xFE0B,0xFE0C,0xFE0D,0xFE0E,0xFE0F,0xFE20,0xFE21, 0xFE22,0xFE23,0xFE24,0xFE25,0xFE26,0xFE27,0xFE28,0xFE29, 0xFE2A,0xFE2B,0xFE2C,0xFE2D,0xFE2E,0xFE2F, 0x101FD,0x102E0,0x10376,0x10377,0x10378,0x10379,0x1037A,0x10A01, 0x10A02,0x10A03,0x10A05,0x10A06,0x10A0C,0x10A0D,0x10A0E,0x10A0F, 0x10A38,0x10A39,0x10A3A,0x10A3F,0x10AE5,0x10AE6,0x11001,0x11038, 0x11039,0x1103A,0x1103B,0x1103C,0x1103D,0x1103E,0x1103F,0x11040, 0x11041,0x11042,0x11043,0x11044,0x11045,0x11046,0x1107F,0x11080, 0x11081,0x110B3,0x110B4,0x110B5,0x110B6,0x110B9,0x110BA,0x11100, 0x11101,0x11102,0x11127,0x11128,0x11129,0x1112A,0x1112B,0x1112D, 0x1112E,0x1112F,0x11130,0x11131,0x11132,0x11133,0x11134,0x11173, 0x11180,0x11181,0x111B6,0x111B7,0x111B8,0x111B9,0x111BA,0x111BB, 0x111BC,0x111BD,0x111BE,0x111CA,0x111CB,0x111CC,0x1122F,0x11230, 0x11231,0x11234,0x11236,0x11237,0x1123E,0x112DF,0x112E3,0x112E4, 0x112E5,0x112E6,0x112E7,0x112E8,0x112E9,0x112EA,0x11300,0x11301, 0x1133C,0x11340,0x11366,0x11367,0x11368,0x11369,0x1136A,0x1136B, 0x1136C,0x11370,0x11371,0x11372,0x11373,0x11374,0x11438,0x11439, 0x1143A,0x1143B,0x1143C,0x1143D,0x1143E,0x1143F,0x11442,0x11443, 0x11444,0x11446,0x114B3,0x114B4,0x114B5,0x114B6,0x114B7,0x114B8, 0x114BA,0x114BF,0x114C0,0x114C2,0x114C3,0x115B2,0x115B3,0x115B4, 0x115B5,0x115BC,0x115BD,0x115BF,0x115C0,0x115DC,0x115DD,0x11633, 0x11634,0x11635,0x11636,0x11637,0x11638,0x11639,0x1163A,0x1163D, 0x1163F,0x11640,0x116AB,0x116AD,0x116B0,0x116B1,0x116B2,0x116B3, 0x116B4,0x116B5,0x116B7,0x1171D,0x1171E,0x1171F,0x11722,0x11723, 0x11724,0x11725,0x11727,0x11728,0x11729,0x1172A,0x1172B,0x11C30, 0x11C31,0x11C32,0x11C33,0x11C34,0x11C35,0x11C36,0x11C38,0x11C39, 0x11C3A,0x11C3B,0x11C3C,0x11C3D,0x11C3F,0x11C92,0x11C93,0x11C94, 0x11C95,0x11C96,0x11C97,0x11C98,0x11C99,0x11C9A,0x11C9B,0x11C9C, 0x11C9D,0x11C9E,0x11C9F,0x11CA0,0x11CA1,0x11CA2,0x11CA3,0x11CA4, 0x11CA5,0x11CA6,0x11CA7,0x11CAA,0x11CAB,0x11CAC,0x11CAD,0x11CAE, 0x11CAF,0x11CB0,0x11CB2,0x11CB3,0x11CB5,0x11CB6,0x16AF0,0x16AF1, 0x16AF2,0x16AF3,0x16AF4,0x16B30,0x16B31,0x16B32,0x16B33,0x16B34, 0x16B35,0x16B36,0x16F8F,0x16F90,0x16F91,0x16F92,0x1BC9D,0x1BC9E, 0x1D167,0x1D168,0x1D169,0x1D17B,0x1D17C,0x1D17D,0x1D17E,0x1D17F, 0x1D180,0x1D181,0x1D182,0x1D185,0x1D186,0x1D187,0x1D188,0x1D189, 0x1D18A,0x1D18B,0x1D1AA,0x1D1AB,0x1D1AC,0x1D1AD,0x1D242,0x1D243, 0x1D244,0x1DA00,0x1DA01,0x1DA02,0x1DA03,0x1DA04,0x1DA05,0x1DA06, 0x1DA07,0x1DA08,0x1DA09,0x1DA0A,0x1DA0B,0x1DA0C,0x1DA0D,0x1DA0E, 0x1DA0F,0x1DA10,0x1DA11,0x1DA12,0x1DA13,0x1DA14,0x1DA15,0x1DA16, 0x1DA17,0x1DA18,0x1DA19,0x1DA1A,0x1DA1B,0x1DA1C,0x1DA1D,0x1DA1E, 0x1DA1F,0x1DA20,0x1DA21,0x1DA22,0x1DA23,0x1DA24,0x1DA25,0x1DA26, 0x1DA27,0x1DA28,0x1DA29,0x1DA2A,0x1DA2B,0x1DA2C,0x1DA2D,0x1DA2E, 0x1DA2F,0x1DA30,0x1DA31,0x1DA32,0x1DA33,0x1DA34,0x1DA35,0x1DA36, 0x1DA3B,0x1DA3C,0x1DA3D,0x1DA3E,0x1DA3F,0x1DA40,0x1DA41,0x1DA42, 0x1DA43,0x1DA44,0x1DA45,0x1DA46,0x1DA47,0x1DA48,0x1DA49,0x1DA4A, 0x1DA4B,0x1DA4C,0x1DA4D,0x1DA4E,0x1DA4F,0x1DA50,0x1DA51,0x1DA52, 0x1DA53,0x1DA54,0x1DA55,0x1DA56,0x1DA57,0x1DA58,0x1DA59,0x1DA5A, 0x1DA5B,0x1DA5C,0x1DA5D,0x1DA5E,0x1DA5F,0x1DA60,0x1DA61,0x1DA62, 0x1DA63,0x1DA64,0x1DA65,0x1DA66,0x1DA67,0x1DA68,0x1DA69,0x1DA6A, 0x1DA6B,0x1DA6C,0x1DA75,0x1DA84,0x1DA9B,0x1DA9C,0x1DA9D,0x1DA9E, 0x1DA9F,0x1DAA1,0x1DAA2,0x1DAA3,0x1DAA4,0x1DAA5,0x1DAA6,0x1DAA7, 0x1DAA8,0x1DAA9,0x1DAAA,0x1DAAB,0x1DAAC,0x1DAAD,0x1DAAE,0x1DAAF, 0x1E000,0x1E001,0x1E002,0x1E003,0x1E004,0x1E005,0x1E006,0x1E008, 0x1E009,0x1E00A,0x1E00B,0x1E00C,0x1E00D,0x1E00E,0x1E00F,0x1E010, 0x1E011,0x1E012,0x1E013,0x1E014,0x1E015,0x1E016,0x1E017,0x1E018, 0x1E01B,0x1E01C,0x1E01D,0x1E01E,0x1E01F,0x1E020,0x1E021,0x1E023, 0x1E024,0x1E026,0x1E027,0x1E028,0x1E029,0x1E02A,0x1E8D0,0x1E8D1, 0x1E8D2,0x1E8D3,0x1E8D4,0x1E8D5,0x1E8D6,0x1E944,0x1E945,0x1E946, 0x1E947,0x1E948,0x1E949,0x1E94A,0xE0100,0xE0101,0xE0102,0xE0103, 0xE0104,0xE0105,0xE0106,0xE0107,0xE0108,0xE0109,0xE010A,0xE010B, 0xE010C,0xE010D,0xE010E,0xE010F,0xE0110,0xE0111,0xE0112,0xE0113, 0xE0114,0xE0115,0xE0116,0xE0117,0xE0118,0xE0119,0xE011A,0xE011B, 0xE011C,0xE011D,0xE011E,0xE011F,0xE0120,0xE0121,0xE0122,0xE0123, 0xE0124,0xE0125,0xE0126,0xE0127,0xE0128,0xE0129,0xE012A,0xE012B, 0xE012C,0xE012D,0xE012E,0xE012F,0xE0130,0xE0131,0xE0132,0xE0133, 0xE0134,0xE0135,0xE0136,0xE0137,0xE0138,0xE0139,0xE013A,0xE013B, 0xE013C,0xE013D,0xE013E,0xE013F,0xE0140,0xE0141,0xE0142,0xE0143, 0xE0144,0xE0145,0xE0146,0xE0147,0xE0148,0xE0149,0xE014A,0xE014B, 0xE014C,0xE014D,0xE014E,0xE014F,0xE0150,0xE0151,0xE0152,0xE0153, 0xE0154,0xE0155,0xE0156,0xE0157,0xE0158,0xE0159,0xE015A,0xE015B, 0xE015C,0xE015D,0xE015E,0xE015F,0xE0160,0xE0161,0xE0162,0xE0163, 0xE0164,0xE0165,0xE0166,0xE0167,0xE0168,0xE0169,0xE016A,0xE016B, 0xE016C,0xE016D,0xE016E,0xE016F,0xE0170,0xE0171,0xE0172,0xE0173, 0xE0174,0xE0175,0xE0176,0xE0177,0xE0178,0xE0179,0xE017A,0xE017B, 0xE017C,0xE017D,0xE017E,0xE017F,0xE0180,0xE0181,0xE0182,0xE0183, 0xE0184,0xE0185,0xE0186,0xE0187,0xE0188,0xE0189,0xE018A,0xE018B, 0xE018C,0xE018D,0xE018E,0xE018F,0xE0190,0xE0191,0xE0192,0xE0193, 0xE0194,0xE0195,0xE0196,0xE0197,0xE0198,0xE0199,0xE019A,0xE019B, 0xE019C,0xE019D,0xE019E,0xE019F,0xE01A0,0xE01A1,0xE01A2,0xE01A3, 0xE01A4,0xE01A5,0xE01A6,0xE01A7,0xE01A8,0xE01A9,0xE01AA,0xE01AB, 0xE01AC,0xE01AD,0xE01AE,0xE01AF,0xE01B0,0xE01B1,0xE01B2,0xE01B3, 0xE01B4,0xE01B5,0xE01B6,0xE01B7,0xE01B8,0xE01B9,0xE01BA,0xE01BB, 0xE01BC,0xE01BD,0xE01BE,0xE01BF,0xE01C0,0xE01C1,0xE01C2,0xE01C3, 0xE01C4,0xE01C5,0xE01C6,0xE01C7,0xE01C8,0xE01C9,0xE01CA,0xE01CB, 0xE01CC,0xE01CD,0xE01CE,0xE01CF,0xE01D0,0xE01D1,0xE01D2,0xE01D3, 0xE01D4,0xE01D5,0xE01D6,0xE01D7,0xE01D8,0xE01D9,0xE01DA,0xE01DB, 0xE01DC,0xE01DD,0xE01DE,0xE01DF,0xE01E0,0xE01E1,0xE01E2,0xE01E3, 0xE01E4,0xE01E5,0xE01E6,0xE01E7,0xE01E8,0xE01E9,0xE01EA,0xE01EB, 0xE01EC,0xE01ED,0xE01EE,0xE01EF, }; /// The length of the combining characters list. const size_t bc_history_combo_chars_len = sizeof(bc_history_combo_chars) / sizeof(bc_history_combo_chars[0]); #endif // BC_ENABLE_HISTORY /// The human-readable name of the main function in bc source code. const char bc_func_main[] = "(main)"; /// The human-readable name of the read function in bc source code. const char bc_func_read[] = "(read)"; #if BC_DEBUG_CODE /// A list of names of instructions for easy debugging output. const char* bc_inst_names[] = { #if BC_ENABLED "BC_INST_INC", "BC_INST_DEC", #endif // BC_ENABLED "BC_INST_NEG", "BC_INST_BOOL_NOT", #if BC_ENABLE_EXTRA_MATH "BC_INST_TRUNC", #endif // BC_ENABLE_EXTRA_MATH "BC_INST_POWER", "BC_INST_MULTIPLY", "BC_INST_DIVIDE", "BC_INST_MODULUS", "BC_INST_PLUS", "BC_INST_MINUS", #if BC_ENABLE_EXTRA_MATH "BC_INST_PLACES", "BC_INST_LSHIFT", "BC_INST_RSHIFT", #endif // BC_ENABLE_EXTRA_MATH "BC_INST_REL_EQ", "BC_INST_REL_LE", "BC_INST_REL_GE", "BC_INST_REL_NE", "BC_INST_REL_LT", "BC_INST_REL_GT", "BC_INST_BOOL_OR", "BC_INST_BOOL_AND", #if BC_ENABLED "BC_INST_ASSIGN_POWER", "BC_INST_ASSIGN_MULTIPLY", "BC_INST_ASSIGN_DIVIDE", "BC_INST_ASSIGN_MODULUS", "BC_INST_ASSIGN_PLUS", "BC_INST_ASSIGN_MINUS", #if BC_ENABLE_EXTRA_MATH "BC_INST_ASSIGN_PLACES", "BC_INST_ASSIGN_LSHIFT", "BC_INST_ASSIGN_RSHIFT", #endif // BC_ENABLE_EXTRA_MATH "BC_INST_ASSIGN", "BC_INST_ASSIGN_POWER_NO_VAL", "BC_INST_ASSIGN_MULTIPLY_NO_VAL", "BC_INST_ASSIGN_DIVIDE_NO_VAL", "BC_INST_ASSIGN_MODULUS_NO_VAL", "BC_INST_ASSIGN_PLUS_NO_VAL", "BC_INST_ASSIGN_MINUS_NO_VAL", #if BC_ENABLE_EXTRA_MATH "BC_INST_ASSIGN_PLACES_NO_VAL", "BC_INST_ASSIGN_LSHIFT_NO_VAL", "BC_INST_ASSIGN_RSHIFT_NO_VAL", #endif // BC_ENABLE_EXTRA_MATH #endif // BC_ENABLED "BC_INST_ASSIGN_NO_VAL", "BC_INST_NUM", "BC_INST_VAR", "BC_INST_ARRAY_ELEM", "BC_INST_ARRAY", "BC_INST_ZERO", "BC_INST_ONE", #if BC_ENABLED "BC_INST_LAST", #endif // BC_ENABLED "BC_INST_IBASE", "BC_INST_OBASE", "BC_INST_SCALE", #if BC_ENABLE_EXTRA_MATH "BC_INST_SEED", #endif // BC_ENABLE_EXTRA_MATH "BC_INST_LENGTH", "BC_INST_SCALE_FUNC", "BC_INST_SQRT", "BC_INST_ABS", #if BC_ENABLE_EXTRA_MATH "BC_INST_IRAND", #endif // BC_ENABLE_EXTRA_MATH "BC_INST_ASCIIFY", "BC_INST_READ", #if BC_ENABLE_EXTRA_MATH "BC_INST_RAND", #endif // BC_ENABLE_EXTRA_MATH "BC_INST_MAXIBASE", "BC_INST_MAXOBASE", "BC_INST_MAXSCALE", #if BC_ENABLE_EXTRA_MATH "BC_INST_MAXRAND", #endif // BC_ENABLE_EXTRA_MATH "BC_INST_PRINT", "BC_INST_PRINT_POP", "BC_INST_STR", #if BC_ENABLED "BC_INST_PRINT_STR", "BC_INST_JUMP", "BC_INST_JUMP_ZERO", "BC_INST_CALL", "BC_INST_RET", "BC_INST_RET0", "BC_INST_RET_VOID", "BC_INST_HALT", #endif // BC_ENABLED "BC_INST_POP", "BC_INST_SWAP", "BC_INST_MODEXP", "BC_INST_DIVMOD", "BC_INST_PRINT_STREAM", #if DC_ENABLED "BC_INST_POP_EXEC", "BC_INST_EXECUTE", "BC_INST_EXEC_COND", "BC_INST_PRINT_STACK", "BC_INST_CLEAR_STACK", "BC_INST_REG_STACK_LEN", "BC_INST_STACK_LEN", "BC_INST_DUPLICATE", "BC_INST_LOAD", "BC_INST_PUSH_VAR", "BC_INST_PUSH_TO_VAR", "BC_INST_QUIT", "BC_INST_NQUIT", "BC_INST_EXEC_STACK_LEN", #endif // DC_ENABLED "BC_INST_INVALID", }; #endif // BC_DEBUG_CODE /// A constant string for 0. const char bc_parse_zero[2] = "0"; /// A constant string for 1. const char bc_parse_one[2] = "1"; #if BC_ENABLED /// A list of keywords for bc. This needs to be updated if keywords change. const BcLexKeyword bc_lex_kws[] = { BC_LEX_KW_ENTRY("auto", 4, true), BC_LEX_KW_ENTRY("break", 5, true), BC_LEX_KW_ENTRY("continue", 8, false), BC_LEX_KW_ENTRY("define", 6, true), BC_LEX_KW_ENTRY("for", 3, true), BC_LEX_KW_ENTRY("if", 2, true), BC_LEX_KW_ENTRY("limits", 6, false), BC_LEX_KW_ENTRY("return", 6, true), BC_LEX_KW_ENTRY("while", 5, true), BC_LEX_KW_ENTRY("halt", 4, false), BC_LEX_KW_ENTRY("last", 4, false), BC_LEX_KW_ENTRY("ibase", 5, true), BC_LEX_KW_ENTRY("obase", 5, true), BC_LEX_KW_ENTRY("scale", 5, true), #if BC_ENABLE_EXTRA_MATH BC_LEX_KW_ENTRY("seed", 4, false), #endif // BC_ENABLE_EXTRA_MATH BC_LEX_KW_ENTRY("length", 6, true), BC_LEX_KW_ENTRY("print", 5, false), BC_LEX_KW_ENTRY("sqrt", 4, true), BC_LEX_KW_ENTRY("abs", 3, false), #if BC_ENABLE_EXTRA_MATH BC_LEX_KW_ENTRY("irand", 5, false), #endif // BC_ENABLE_EXTRA_MATH BC_LEX_KW_ENTRY("asciify", 7, false), BC_LEX_KW_ENTRY("modexp", 6, false), BC_LEX_KW_ENTRY("divmod", 6, false), BC_LEX_KW_ENTRY("quit", 4, true), BC_LEX_KW_ENTRY("read", 4, false), #if BC_ENABLE_EXTRA_MATH BC_LEX_KW_ENTRY("rand", 4, false), #endif // BC_ENABLE_EXTRA_MATH BC_LEX_KW_ENTRY("maxibase", 8, false), BC_LEX_KW_ENTRY("maxobase", 8, false), BC_LEX_KW_ENTRY("maxscale", 8, false), #if BC_ENABLE_EXTRA_MATH BC_LEX_KW_ENTRY("maxrand", 7, false), #endif // BC_ENABLE_EXTRA_MATH BC_LEX_KW_ENTRY("line_length", 11, false), BC_LEX_KW_ENTRY("global_stacks", 13, false), BC_LEX_KW_ENTRY("leading_zero", 12, false), BC_LEX_KW_ENTRY("stream", 6, false), BC_LEX_KW_ENTRY("else", 4, false), }; /// The length of the list of bc keywords. const size_t bc_lex_kws_len = sizeof(bc_lex_kws) / sizeof(BcLexKeyword); #if BC_C11 // This is here to ensure that BC_LEX_NKWS, which is needed for the // redefined_kws in BcVm, is correct. If it's correct under C11, it will be // correct under C99, and I did not know any other way of ensuring they remained // synchronized. static_assert(sizeof(bc_lex_kws) / sizeof(BcLexKeyword) == BC_LEX_NKWS, "BC_LEX_NKWS is wrong."); #endif // BC_C11 /// An array of booleans that correspond to token types. An entry is true if the /// token is valid in an expression, false otherwise. This will need to change /// if tokens change. const uint8_t bc_parse_exprs[] = { // Starts with BC_LEX_EOF. BC_PARSE_EXPR_ENTRY(false, false, true, true, true, true, true, true), // Starts with BC_LEX_OP_MULTIPLY if extra math is enabled, BC_LEX_OP_DIVIDE // otherwise. BC_PARSE_EXPR_ENTRY(true, true, true, true, true, true, true, true), // Starts with BC_LEX_OP_REL_EQ if extra math is enabled, BC_LEX_OP_REL_LT // otherwise. BC_PARSE_EXPR_ENTRY(true, true, true, true, true, true, true, true), #if BC_ENABLE_EXTRA_MATH // Starts with BC_LEX_OP_ASSIGN_POWER. BC_PARSE_EXPR_ENTRY(true, true, true, true, true, true, true, true), // Starts with BC_LEX_OP_ASSIGN_RSHIFT. BC_PARSE_EXPR_ENTRY(true, true, false, false, true, true, false, false), // Starts with BC_LEX_RBRACKET. BC_PARSE_EXPR_ENTRY(false, false, false, false, true, true, true, false), // Starts with BC_LEX_KW_BREAK. BC_PARSE_EXPR_ENTRY(false, false, false, false, false, false, false, false), // Starts with BC_LEX_KW_HALT. BC_PARSE_EXPR_ENTRY(false, true, true, true, true, true, true, false), // Starts with BC_LEX_KW_SQRT. BC_PARSE_EXPR_ENTRY(true, true, true, true, true, true, false, true), // Starts with BC_LEX_KW_MAXIBASE. BC_PARSE_EXPR_ENTRY(true, true, true, true, true, true, true, true), // Starts with BC_LEX_KW_STREAM. BC_PARSE_EXPR_ENTRY(false, false, 0, 0, 0, 0, 0, 0) #else // BC_ENABLE_EXTRA_MATH // Starts with BC_LEX_OP_ASSIGN_PLUS. BC_PARSE_EXPR_ENTRY(true, true, true, false, false, true, true, false), // Starts with BC_LEX_COMMA. BC_PARSE_EXPR_ENTRY(false, false, false, false, false, true, true, true), // Starts with BC_LEX_KW_AUTO. BC_PARSE_EXPR_ENTRY(false, false, false, false, false, false, false, false), // Starts with BC_LEX_KW_WHILE. BC_PARSE_EXPR_ENTRY(false, false, true, true, true, true, true, false), // Starts with BC_LEX_KW_SQRT. BC_PARSE_EXPR_ENTRY(true, true, true, true, true, false, true, true), // Starts with BC_LEX_KW_MAXSCALE, BC_PARSE_EXPR_ENTRY(true, true, true, true, true, false, false, 0) #endif // BC_ENABLE_EXTRA_MATH }; /// An array of data for operators that correspond to token types. const uchar bc_parse_ops[] = { BC_PARSE_OP(0, false), BC_PARSE_OP(0, false), BC_PARSE_OP(1, false), BC_PARSE_OP(1, false), #if BC_ENABLE_EXTRA_MATH BC_PARSE_OP(2, false), #endif // BC_ENABLE_EXTRA_MATH BC_PARSE_OP(4, false), BC_PARSE_OP(5, true), BC_PARSE_OP(5, true), BC_PARSE_OP(5, true), BC_PARSE_OP(6, true), BC_PARSE_OP(6, true), #if BC_ENABLE_EXTRA_MATH BC_PARSE_OP(3, false), BC_PARSE_OP(7, true), BC_PARSE_OP(7, true), #endif // BC_ENABLE_EXTRA_MATH BC_PARSE_OP(9, true), BC_PARSE_OP(9, true), BC_PARSE_OP(9, true), BC_PARSE_OP(9, true), BC_PARSE_OP(9, true), BC_PARSE_OP(9, true), BC_PARSE_OP(11, true), BC_PARSE_OP(10, true), BC_PARSE_OP(8, false), BC_PARSE_OP(8, false), BC_PARSE_OP(8, false), BC_PARSE_OP(8, false), BC_PARSE_OP(8, false), BC_PARSE_OP(8, false), #if BC_ENABLE_EXTRA_MATH BC_PARSE_OP(8, false), BC_PARSE_OP(8, false), BC_PARSE_OP(8, false), #endif // BC_ENABLE_EXTRA_MATH BC_PARSE_OP(8, false), }; // These identify what tokens can come after expressions in certain cases. /// The valid next tokens for normal expressions. const BcParseNext bc_parse_next_expr = BC_PARSE_NEXT(4, BC_LEX_NLINE, BC_LEX_SCOLON, BC_LEX_RBRACE, BC_LEX_EOF); /// The valid next tokens for function argument expressions. const BcParseNext bc_parse_next_arg = BC_PARSE_NEXT(2, BC_LEX_RPAREN, BC_LEX_COMMA); /// The valid next tokens for expressions in print statements. const BcParseNext bc_parse_next_print = BC_PARSE_NEXT(4, BC_LEX_COMMA, BC_LEX_NLINE, BC_LEX_SCOLON, BC_LEX_EOF); /// The valid next tokens for if statement conditions or loop conditions. This /// is used in for loops for the update expression and for builtin function. /// /// The name is an artifact of history, and is related to @a BC_PARSE_REL (see /// include/parse.h). It refers to how POSIX only allows some operators as part /// of the conditional of for loops, while loops, and if statements. const BcParseNext bc_parse_next_rel = BC_PARSE_NEXT(1, BC_LEX_RPAREN); /// The valid next tokens for array element expressions. const BcParseNext bc_parse_next_elem = BC_PARSE_NEXT(1, BC_LEX_RBRACKET); /// The valid next tokens for for loop initialization expressions and condition /// expressions. const BcParseNext bc_parse_next_for = BC_PARSE_NEXT(1, BC_LEX_SCOLON); /// The valid next tokens for read expressions. const BcParseNext bc_parse_next_read = BC_PARSE_NEXT(2, BC_LEX_NLINE, BC_LEX_EOF); /// The valid next tokens for the arguments of a builtin function with multiple /// arguments. const BcParseNext bc_parse_next_builtin = BC_PARSE_NEXT(1, BC_LEX_COMMA); #endif // BC_ENABLED #if DC_ENABLED /// A list of instructions that need register arguments in dc. const uint8_t dc_lex_regs[] = { BC_LEX_OP_REL_EQ, BC_LEX_OP_REL_LE, BC_LEX_OP_REL_GE, BC_LEX_OP_REL_NE, BC_LEX_OP_REL_LT, BC_LEX_OP_REL_GT, BC_LEX_SCOLON, BC_LEX_COLON, BC_LEX_KW_ELSE, BC_LEX_LOAD, BC_LEX_LOAD_POP, BC_LEX_OP_ASSIGN, BC_LEX_STORE_PUSH, BC_LEX_REG_STACK_LEVEL, BC_LEX_ARRAY_LENGTH, }; /// The length of the list of register instructions. const size_t dc_lex_regs_len = sizeof(dc_lex_regs) / sizeof(uint8_t); /// A list corresponding to characters starting at double quote ("). If an entry /// is BC_LEX_INVALID, then that character needs extra lexing in dc. If it does /// not, the character can trivially be replaced by the entry. Positions are /// kept because it corresponds to the ASCII table. This may need to be changed /// if tokens change. const uchar dc_lex_tokens[] = { #if BC_ENABLE_EXTRA_MATH BC_LEX_KW_IRAND, #else // BC_ENABLE_EXTRA_MATH BC_LEX_INVALID, #endif // BC_ENABLE_EXTRA_MATH BC_LEX_INVALID, #if BC_ENABLE_EXTRA_MATH BC_LEX_OP_TRUNC, #else // BC_ENABLE_EXTRA_MATH BC_LEX_INVALID, #endif // BC_ENABLE_EXTRA_MATH BC_LEX_OP_MODULUS, BC_LEX_INVALID, #if BC_ENABLE_EXTRA_MATH BC_LEX_KW_RAND, #else // BC_ENABLE_EXTRA_MATH BC_LEX_INVALID, #endif // BC_ENABLE_EXTRA_MATH BC_LEX_LPAREN, BC_LEX_RPAREN, BC_LEX_OP_MULTIPLY, BC_LEX_OP_PLUS, BC_LEX_EXEC_STACK_LENGTH, BC_LEX_OP_MINUS, BC_LEX_INVALID, BC_LEX_OP_DIVIDE, BC_LEX_INVALID, BC_LEX_INVALID, BC_LEX_INVALID, BC_LEX_INVALID, BC_LEX_INVALID, BC_LEX_INVALID, BC_LEX_INVALID, BC_LEX_INVALID, BC_LEX_INVALID, BC_LEX_INVALID, BC_LEX_COLON, BC_LEX_SCOLON, BC_LEX_OP_REL_GT, BC_LEX_OP_REL_EQ, BC_LEX_OP_REL_LT, BC_LEX_KW_READ, #if BC_ENABLE_EXTRA_MATH BC_LEX_OP_PLACES, #else // BC_ENABLE_EXTRA_MATH BC_LEX_INVALID, #endif // BC_ENABLE_EXTRA_MATH BC_LEX_INVALID, BC_LEX_INVALID, BC_LEX_INVALID, BC_LEX_INVALID, BC_LEX_INVALID, BC_LEX_INVALID, BC_LEX_EQ_NO_REG, #if BC_ENABLE_EXTRA_MATH BC_LEX_OP_LSHIFT, #else // BC_ENABLE_EXTRA_MATH BC_LEX_INVALID, #endif // BC_ENABLE_EXTRA_MATH BC_LEX_KW_IBASE, #if BC_ENABLE_EXTRA_MATH BC_LEX_KW_SEED, #else // BC_ENABLE_EXTRA_MATH BC_LEX_INVALID, #endif // BC_ENABLE_EXTRA_MATH BC_LEX_KW_SCALE, BC_LEX_LOAD_POP, BC_LEX_OP_BOOL_AND, BC_LEX_OP_BOOL_NOT, BC_LEX_KW_OBASE, BC_LEX_KW_STREAM, BC_LEX_NQUIT, BC_LEX_POP, BC_LEX_STORE_PUSH, BC_LEX_KW_MAXIBASE, BC_LEX_KW_MAXOBASE, BC_LEX_KW_MAXSCALE, #if BC_ENABLE_EXTRA_MATH BC_LEX_KW_MAXRAND, #else // BC_ENABLE_EXTRA_MATH BC_LEX_INVALID, #endif // BC_ENABLE_EXTRA_MATH BC_LEX_SCALE_FACTOR, BC_LEX_ARRAY_LENGTH, BC_LEX_KW_LENGTH, BC_LEX_INVALID, BC_LEX_INVALID, BC_LEX_INVALID, BC_LEX_OP_POWER, BC_LEX_NEG, BC_LEX_INVALID, BC_LEX_KW_ASCIIFY, BC_LEX_KW_ABS, BC_LEX_CLEAR_STACK, BC_LEX_DUPLICATE, BC_LEX_KW_ELSE, BC_LEX_PRINT_STACK, BC_LEX_INVALID, #if BC_ENABLE_EXTRA_MATH BC_LEX_OP_RSHIFT, #else // BC_ENABLE_EXTRA_MATH BC_LEX_INVALID, #endif // BC_ENABLE_EXTRA_MATH BC_LEX_STORE_IBASE, #if BC_ENABLE_EXTRA_MATH BC_LEX_STORE_SEED, #else // BC_ENABLE_EXTRA_MATH BC_LEX_INVALID, #endif // BC_ENABLE_EXTRA_MATH BC_LEX_STORE_SCALE, BC_LEX_LOAD, BC_LEX_OP_BOOL_OR, BC_LEX_PRINT_POP, BC_LEX_STORE_OBASE, BC_LEX_KW_PRINT, BC_LEX_KW_QUIT, BC_LEX_SWAP, BC_LEX_OP_ASSIGN, BC_LEX_INVALID, BC_LEX_INVALID, BC_LEX_KW_SQRT, BC_LEX_INVALID, BC_LEX_EXECUTE, BC_LEX_REG_STACK_LEVEL, BC_LEX_STACK_LEVEL, BC_LEX_LBRACE, BC_LEX_KW_MODEXP, BC_LEX_RBRACE, BC_LEX_KW_DIVMOD, BC_LEX_INVALID }; /// A list of instructions that correspond to lex tokens. If an entry is /// BC_INST_INVALID, that lex token needs extra parsing in the dc parser. /// Otherwise, the token can trivially be replaced by the entry. This needs to /// be updated if the tokens change. const uchar dc_parse_insts[] = { BC_INST_INVALID, BC_INST_INVALID, #if BC_ENABLED BC_INST_INVALID, BC_INST_INVALID, #endif // BC_ENABLED BC_INST_INVALID, BC_INST_BOOL_NOT, #if BC_ENABLE_EXTRA_MATH BC_INST_TRUNC, #endif // BC_ENABLE_EXTRA_MATH BC_INST_POWER, BC_INST_MULTIPLY, BC_INST_DIVIDE, BC_INST_MODULUS, BC_INST_PLUS, BC_INST_MINUS, #if BC_ENABLE_EXTRA_MATH BC_INST_PLACES, BC_INST_LSHIFT, BC_INST_RSHIFT, #endif // BC_ENABLE_EXTRA_MATH BC_INST_INVALID, BC_INST_INVALID, BC_INST_INVALID, BC_INST_INVALID, BC_INST_INVALID, BC_INST_INVALID, BC_INST_BOOL_OR, BC_INST_BOOL_AND, #if BC_ENABLED BC_INST_INVALID, BC_INST_INVALID, BC_INST_INVALID, BC_INST_INVALID, BC_INST_INVALID, BC_INST_INVALID, #if BC_ENABLE_EXTRA_MATH BC_INST_INVALID, BC_INST_INVALID, BC_INST_INVALID, #endif // BC_ENABLE_EXTRA_MATH #endif // BC_ENABLED BC_INST_INVALID, BC_INST_INVALID, BC_INST_INVALID, BC_INST_REL_GT, BC_INST_REL_LT, BC_INST_INVALID, BC_INST_INVALID, BC_INST_INVALID, BC_INST_REL_GE, BC_INST_INVALID, BC_INST_REL_LE, BC_INST_INVALID, BC_INST_INVALID, BC_INST_INVALID, #if BC_ENABLED BC_INST_INVALID, BC_INST_INVALID, BC_INST_INVALID, BC_INST_INVALID, BC_INST_INVALID, BC_INST_INVALID, BC_INST_INVALID, BC_INST_INVALID, BC_INST_INVALID, BC_INST_INVALID, BC_INST_INVALID, #endif // BC_ENABLED BC_INST_IBASE, BC_INST_OBASE, BC_INST_SCALE, #if BC_ENABLE_EXTRA_MATH BC_INST_SEED, #endif // BC_ENABLE_EXTRA_MATH BC_INST_LENGTH, BC_INST_PRINT, BC_INST_SQRT, BC_INST_ABS, #if BC_ENABLE_EXTRA_MATH BC_INST_IRAND, #endif // BC_ENABLE_EXTRA_MATH BC_INST_ASCIIFY, BC_INST_MODEXP, BC_INST_DIVMOD, BC_INST_QUIT, BC_INST_INVALID, #if BC_ENABLE_EXTRA_MATH BC_INST_RAND, #endif // BC_ENABLE_EXTRA_MATH BC_INST_MAXIBASE, BC_INST_MAXOBASE, BC_INST_MAXSCALE, #if BC_ENABLE_EXTRA_MATH BC_INST_MAXRAND, #endif // BC_ENABLE_EXTRA_MATH BC_INST_LINE_LENGTH, #if BC_ENABLED BC_INST_INVALID, #endif // BC_ENABLED BC_INST_LEADING_ZERO, BC_INST_PRINT_STREAM, BC_INST_INVALID, BC_INST_REL_EQ, BC_INST_INVALID, BC_INST_EXECUTE, BC_INST_PRINT_STACK, BC_INST_CLEAR_STACK, BC_INST_INVALID, BC_INST_STACK_LEN, BC_INST_DUPLICATE, BC_INST_SWAP, BC_INST_POP, BC_INST_INVALID, BC_INST_INVALID, BC_INST_INVALID, #if BC_ENABLE_EXTRA_MATH BC_INST_INVALID, #endif // BC_ENABLE_EXTRA_MATH BC_INST_INVALID, BC_INST_INVALID, BC_INST_INVALID, BC_INST_PRINT_POP, BC_INST_NQUIT, BC_INST_EXEC_STACK_LEN, BC_INST_SCALE_FUNC, BC_INST_INVALID, }; #endif // DC_ENABLED #endif // !BC_ENABLE_LIBRARY #if BC_ENABLE_EXTRA_MATH /// A constant for the rand multiplier. const BcRandState bc_rand_multiplier = BC_RAND_MULTIPLIER; #endif // BC_ENABLE_EXTRA_MATH #if BC_LONG_BIT >= 64 /// A constant array for the max of a bigdig number as a BcDig array. const BcDig bc_num_bigdigMax[] = { 709551616U, 446744073U, 18U, }; /// A constant array for the max of 2 times a bigdig number as a BcDig array. const BcDig bc_num_bigdigMax2[] = { 768211456U, 374607431U, 938463463U, 282366920U, 340U, }; #else // BC_LONG_BIT >= 64 /// A constant array for the max of a bigdig number as a BcDig array. const BcDig bc_num_bigdigMax[] = { 7296U, 9496U, 42U, }; /// A constant array for the max of 2 times a bigdig number as a BcDig array. const BcDig bc_num_bigdigMax2[] = { 1616U, 955U, 737U, 6744U, 1844U, }; #endif // BC_LONG_BIT >= 64 /// The size of the bigdig max array. const size_t bc_num_bigdigMax_size = sizeof(bc_num_bigdigMax) / sizeof(BcDig); /// The size of the bigdig max times 2 array. const size_t bc_num_bigdigMax2_size = sizeof(bc_num_bigdigMax2) / sizeof(BcDig); /// A string of digits for easy conversion from characters to digits. const char bc_num_hex_digits[] = "0123456789ABCDEF"; /// An array for easy conversion from exponent to power of 10. const BcBigDig bc_num_pow10[BC_BASE_DIGS + 1] = { 1, 10, 100, 1000, 10000, #if BC_BASE_DIGS > 4 100000, 1000000, 10000000, 100000000, 1000000000, #endif // BC_BASE_DIGS > 4 }; #if !BC_ENABLE_LIBRARY /// An array of functions for binary operators corresponding to the order of /// the instructions for the operators. const BcNumBinaryOp bc_program_ops[] = { bc_num_pow, bc_num_mul, bc_num_div, bc_num_mod, bc_num_add, bc_num_sub, #if BC_ENABLE_EXTRA_MATH bc_num_places, bc_num_lshift, bc_num_rshift, #endif // BC_ENABLE_EXTRA_MATH }; /// An array of functions for binary operators allocation requests corresponding /// to the order of the instructions for the operators. const BcNumBinaryOpReq bc_program_opReqs[] = { bc_num_powReq, bc_num_mulReq, bc_num_divReq, bc_num_divReq, bc_num_addReq, bc_num_addReq, #if BC_ENABLE_EXTRA_MATH bc_num_placesReq, bc_num_placesReq, bc_num_placesReq, #endif // BC_ENABLE_EXTRA_MATH }; /// An array of unary operator functions corresponding to the order of the /// instructions. const BcProgramUnary bc_program_unarys[] = { bc_program_negate, bc_program_not, #if BC_ENABLE_EXTRA_MATH bc_program_trunc, #endif // BC_ENABLE_EXTRA_MATH }; /// A filename for when parsing expressions. const char bc_program_exprs_name[] = ""; /// A filename for when parsing stdin.. const char bc_program_stdin_name[] = ""; /// A ready message for SIGINT catching. const char bc_program_ready_msg[] = "ready for more input\n"; /// The length of the ready message. const size_t bc_program_ready_msg_len = sizeof(bc_program_ready_msg) - 1; /// A list of escape characters that a print statement should treat specially. const char bc_program_esc_chars[] = "ab\\efnqrt"; /// A list of characters corresponding to the escape characters above. const char bc_program_esc_seqs[] = "\a\b\\\\\f\n\"\r\t"; #endif // !BC_ENABLE_LIBRARY diff --git a/contrib/bc/src/dc_lex.c b/contrib/bc/src/dc_lex.c index 5c6950ba9698..576d50943f25 100644 --- a/contrib/bc/src/dc_lex.c +++ b/contrib/bc/src/dc_lex.c @@ -1,276 +1,278 @@ /* * ***************************************************************************** * * SPDX-License-Identifier: BSD-2-Clause * * Copyright (c) 2018-2021 Gavin D. Howard and contributors. * * Redistribution and use in source and binary forms, with or without * modification, are permitted provided that the following conditions are met: * * * Redistributions of source code must retain the above copyright notice, this * list of conditions and the following disclaimer. * * * Redistributions in binary form must reproduce the above copyright notice, * this list of conditions and the following disclaimer in the documentation * and/or other materials provided with the distribution. * * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE * POSSIBILITY OF SUCH DAMAGE. * * ***************************************************************************** * * The lexer for dc. * */ #if DC_ENABLED #include #include #include bool dc_lex_negCommand(BcLex *l) { char c = l->buf[l->i]; return !BC_LEX_NUM_CHAR(c, false, false); } /** * Processes a dc command that needs a register. This is where the * extended-register extension is implemented. * @param l The lexer. */ static void dc_lex_register(BcLex *l) { // If extended register is enabled and the character is whitespace... if (DC_X && isspace(l->buf[l->i - 1])) { char c; // Eat the whitespace. bc_lex_whitespace(l); c = l->buf[l->i]; // Check for a letter or underscore. if (BC_ERR(!isalpha(c) && c != '_')) bc_lex_verr(l, BC_ERR_PARSE_CHAR, c); // Parse a normal identifier. l->i += 1; bc_lex_name(l); } else { // I don't allow newlines because newlines are used for controlling when // execution happens, and allowing newlines would just be complex. if (BC_ERR(l->buf[l->i - 1] == '\n')) bc_lex_verr(l, BC_ERR_PARSE_CHAR, l->buf[l->i - 1]); // Set the lexer string and token. bc_vec_popAll(&l->str); bc_vec_pushByte(&l->str, (uchar) l->buf[l->i - 1]); bc_vec_pushByte(&l->str, '\0'); l->t = BC_LEX_NAME; } } /** * Parses a dc string. Since dc's strings need to check for balanced brackets, * we can't just parse bc and dc strings with different start and end * characters. Oh, and dc strings need to check for escaped brackets. * @param l The lexer. */ static void dc_lex_string(BcLex *l) { size_t depth, nls, i; char c; bool got_more; // Set the token and clear the string. l->t = BC_LEX_STR; bc_vec_popAll(&l->str); do { depth = 1; nls = 0; got_more = false; assert(!l->is_stdin || l->buf == vm.buffer.v); // This is the meat. As long as we don't run into the NUL byte, and we // have "depth", which means we haven't completely balanced brackets // yet, we continue eating the string. for (i = l->i; (c = l->buf[i]) && depth; ++i) { // Check for escaped brackets and set the depths as appropriate. if (c == '\\') { c = l->buf[++i]; if (!c) break; } else { depth += (c == '['); depth -= (c == ']'); } // We want to adjust the line in the lexer as necessary. nls += (c == '\n'); if (depth) bc_vec_push(&l->str, &c); } if (BC_ERR(c == '\0' && depth)) { if (!vm.eof && l->is_stdin) got_more = bc_lex_readLine(l); if (got_more) bc_vec_popAll(&l->str); } } while (got_more && depth); // Obviously, if we didn't balance, that's an error. if (BC_ERR(c == '\0' && depth)) { l->i = i; bc_lex_err(l, BC_ERR_PARSE_STRING); } bc_vec_pushByte(&l->str, '\0'); l->i = i; l->line += nls; } /** * Lexes a dc token. This is the dc implementation of BcLexNext. * @param l The lexer. */ void dc_lex_token(BcLex *l) { char c = l->buf[l->i++], c2; size_t i; + BC_SIG_ASSERT_LOCKED; + // If the last token was a command that needs a register, we need to parse a // register, so do so. for (i = 0; i < dc_lex_regs_len; ++i) { // If the token is a register token, take care of it and return. if (l->last == dc_lex_regs[i]) { dc_lex_register(l); return; } } // These lines are for tokens that easily correspond to one character. We // just set the token. if (c >= '"' && c <= '~' && (l->t = dc_lex_tokens[(c - '"')]) != BC_LEX_INVALID) { return; } // This is the workhorse of the lexer when more complicated things are // needed. switch (c) { case '\0': case '\n': case '\t': case '\v': case '\f': case '\r': case ' ': { bc_lex_commonTokens(l, c); break; } // We don't have the ! command, so we always expect certain things // after the exclamation point. case '!': { c2 = l->buf[l->i]; if (c2 == '=') l->t = BC_LEX_OP_REL_NE; else if (c2 == '<') l->t = BC_LEX_OP_REL_LE; else if (c2 == '>') l->t = BC_LEX_OP_REL_GE; else bc_lex_invalidChar(l, c); l->i += 1; break; } case '#': { bc_lex_lineComment(l); break; } case '.': { c2 = l->buf[l->i]; // If the character after is a number, this dot is part of a number. // Otherwise, it's the BSD dot (equivalent to last). if (BC_NO_ERR(BC_LEX_NUM_CHAR(c2, true, false))) bc_lex_number(l, c); else bc_lex_invalidChar(l, c); break; } case '0': case '1': case '2': case '3': case '4': case '5': case '6': case '7': case '8': case '9': case 'A': case 'B': case 'C': case 'D': case 'E': case 'F': { bc_lex_number(l, c); break; } case 'g': { c2 = l->buf[l->i]; if (c2 == 'l') l->t = BC_LEX_KW_LINE_LENGTH; else if (c2 == 'z') l->t = BC_LEX_KW_LEADING_ZERO; else bc_lex_invalidChar(l, c2); l->i += 1; break; } case '[': { dc_lex_string(l); break; } default: { bc_lex_invalidChar(l, c); } } } #endif // DC_ENABLED diff --git a/contrib/bc/src/dc_parse.c b/contrib/bc/src/dc_parse.c index b9b5afb66c44..26aad6796d88 100644 --- a/contrib/bc/src/dc_parse.c +++ b/contrib/bc/src/dc_parse.c @@ -1,321 +1,320 @@ /* * ***************************************************************************** * * SPDX-License-Identifier: BSD-2-Clause * * Copyright (c) 2018-2021 Gavin D. Howard and contributors. * * Redistribution and use in source and binary forms, with or without * modification, are permitted provided that the following conditions are met: * * * Redistributions of source code must retain the above copyright notice, this * list of conditions and the following disclaimer. * * * Redistributions in binary form must reproduce the above copyright notice, * this list of conditions and the following disclaimer in the documentation * and/or other materials provided with the distribution. * * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE * POSSIBILITY OF SUCH DAMAGE. * * ***************************************************************************** * * The parser for dc. * */ #if DC_ENABLED #include #include #include #include #include #include #include /** * Parses a register. The lexer should have already lexed the true name of the * register, per extended registers and such. * @param p The parser. * @param var True if the parser is for a variable, false otherwise. */ static void dc_parse_register(BcParse *p, bool var) { bc_lex_next(&p->l); if (p->l.t != BC_LEX_NAME) bc_parse_err(p, BC_ERR_PARSE_TOKEN); bc_parse_pushName(p, p->l.str.v, var); } /** * Parses a dc string. * @param p The parser. */ static inline void dc_parse_string(BcParse *p) { bc_parse_addString(p); bc_lex_next(&p->l); } /** * Parses a token that requires a memory operation, like load or store. * @param p The parser. * @param inst The instruction to push for the memory operation. * @param name Whether the load or store is to a variable or array, and not to * a global. * @param store True if the operation is a store, false otherwise. */ static void dc_parse_mem(BcParse *p, uchar inst, bool name, bool store) { // Push the instruction. bc_parse_push(p, inst); // Parse the register if necessary. if (name) dc_parse_register(p, inst != BC_INST_ARRAY_ELEM); // Stores use the bc assign infrastructure, but they need to do a swap // first. if (store) { bc_parse_push(p, BC_INST_SWAP); bc_parse_push(p, BC_INST_ASSIGN_NO_VAL); } bc_lex_next(&p->l); } /** * Parses a conditional execution instruction. * @param p The parser. * @param inst The instruction for the condition. */ static void dc_parse_cond(BcParse *p, uchar inst) { // Push the instruction for the condition and the conditional execution. bc_parse_push(p, inst); bc_parse_push(p, BC_INST_EXEC_COND); // Parse the register. dc_parse_register(p, true); bc_lex_next(&p->l); // If the next token is an else, parse the else. if (p->l.t == BC_LEX_KW_ELSE) { dc_parse_register(p, true); bc_lex_next(&p->l); } // Otherwise, push a marker for no else. else bc_parse_pushIndex(p, SIZE_MAX); } /** * Parses a token for dc. * @param p The parser. * @param t The token to parse. * @param flags The flags that say what is allowed or not. */ static void dc_parse_token(BcParse *p, BcLexType t, uint8_t flags) { uchar inst; bool assign, get_token = false; switch (t) { case BC_LEX_OP_REL_EQ: case BC_LEX_OP_REL_LE: case BC_LEX_OP_REL_GE: case BC_LEX_OP_REL_NE: case BC_LEX_OP_REL_LT: case BC_LEX_OP_REL_GT: { inst = (uchar) (t - BC_LEX_OP_REL_EQ + BC_INST_REL_EQ); dc_parse_cond(p, inst); break; } case BC_LEX_SCOLON: case BC_LEX_COLON: { dc_parse_mem(p, BC_INST_ARRAY_ELEM, true, t == BC_LEX_COLON); break; } case BC_LEX_STR: { dc_parse_string(p); break; } case BC_LEX_NEG: { // This tells us whether or not the neg is for a command or at the // beginning of a number. If it's a command, push it. Otherwise, // fallthrough and parse the number. if (dc_lex_negCommand(&p->l)) { bc_parse_push(p, BC_INST_NEG); get_token = true; break; } bc_lex_next(&p->l); } // Fallthrough. BC_FALLTHROUGH case BC_LEX_NUMBER: { bc_parse_number(p); // Push the negative instruction if we fell through from above. if (t == BC_LEX_NEG) bc_parse_push(p, BC_INST_NEG); get_token = true; break; } case BC_LEX_KW_READ: { // Make sure the read is not recursive. if (BC_ERR(flags & BC_PARSE_NOREAD)) bc_parse_err(p, BC_ERR_EXEC_REC_READ); else bc_parse_push(p, BC_INST_READ); get_token = true; break; } case BC_LEX_OP_ASSIGN: case BC_LEX_STORE_PUSH: { assign = t == BC_LEX_OP_ASSIGN; inst = assign ? BC_INST_VAR : BC_INST_PUSH_TO_VAR; dc_parse_mem(p, inst, true, assign); break; } case BC_LEX_LOAD: case BC_LEX_LOAD_POP: { inst = t == BC_LEX_LOAD_POP ? BC_INST_PUSH_VAR : BC_INST_LOAD; dc_parse_mem(p, inst, true, false); break; } case BC_LEX_REG_STACK_LEVEL: { dc_parse_mem(p, BC_INST_REG_STACK_LEN, true, false); break; } case BC_LEX_STORE_IBASE: case BC_LEX_STORE_OBASE: case BC_LEX_STORE_SCALE: #if BC_ENABLE_EXTRA_MATH case BC_LEX_STORE_SEED: #endif // BC_ENABLE_EXTRA_MATH { inst = (uchar) (t - BC_LEX_STORE_IBASE + BC_INST_IBASE); dc_parse_mem(p, inst, false, true); break; } case BC_LEX_ARRAY_LENGTH: { // Need to push the array first, based on how length is implemented. bc_parse_push(p, BC_INST_ARRAY); dc_parse_register(p, false); bc_parse_push(p, BC_INST_LENGTH); get_token = true; break; } default: { // All other tokens should be taken care of by the caller, or they // actually *are* invalid. bc_parse_err(p, BC_ERR_PARSE_TOKEN); } } if (get_token) bc_lex_next(&p->l); } void dc_parse_expr(BcParse *p, uint8_t flags) { BcInst inst; BcLexType t; bool need_expr, have_expr = false; need_expr = ((flags & BC_PARSE_NOREAD) != 0); // dc can just keep parsing forever basically, unlike bc, which has to have // a whole bunch of complicated nonsense because its language was horribly // designed. // While we don't have EOF... while ((t = p->l.t) != BC_LEX_EOF) { // Eat newline. if (t == BC_LEX_NLINE) { bc_lex_next(&p->l); continue; } // Get the instruction that corresponds to the token. inst = dc_parse_insts[t]; // If the instruction is invalid, that means we have to do some harder // parsing. So if not invalid, just push the instruction; otherwise, // parse the token. if (inst != BC_INST_INVALID) { bc_parse_push(p, inst); bc_lex_next(&p->l); } else dc_parse_token(p, t, flags); have_expr = true; } // If we don't have an expression and need one, barf. Otherwise, just push a // BC_INST_POP_EXEC if we have EOF and BC_PARSE_NOCALL, which dc uses to // indicate that it is executing a string. if (BC_ERR(need_expr && !have_expr)) bc_err(BC_ERR_EXEC_READ_EXPR); else if (p->l.t == BC_LEX_EOF && (flags & BC_PARSE_NOCALL)) bc_parse_push(p, BC_INST_POP_EXEC); } void dc_parse_parse(BcParse *p) { assert(p != NULL); - BC_SETJMP(exit); + BC_SETJMP_LOCKED(exit); // If we have EOF, someone called this function one too many times. // Otherwise, parse. if (BC_ERR(p->l.t == BC_LEX_EOF)) bc_parse_err(p, BC_ERR_PARSE_EOF); else dc_parse_expr(p, 0); exit: - BC_SIG_MAYLOCK; - // Need to reset if there was an error. if (BC_SIG_EXC) bc_parse_reset(p); BC_LONGJMP_CONT; + BC_SIG_MAYLOCK; } #endif // DC_ENABLED diff --git a/contrib/bc/src/file.c b/contrib/bc/src/file.c index 35a4647dfabf..627664a9c261 100644 --- a/contrib/bc/src/file.c +++ b/contrib/bc/src/file.c @@ -1,311 +1,344 @@ /* * ***************************************************************************** * * SPDX-License-Identifier: BSD-2-Clause * * Copyright (c) 2018-2021 Gavin D. Howard and contributors. * * Redistribution and use in source and binary forms, with or without * modification, are permitted provided that the following conditions are met: * * * Redistributions of source code must retain the above copyright notice, this * list of conditions and the following disclaimer. * * * Redistributions in binary form must reproduce the above copyright notice, * this list of conditions and the following disclaimer in the documentation * and/or other materials provided with the distribution. * * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE * POSSIBILITY OF SUCH DAMAGE. * * ***************************************************************************** * * Code for implementing buffered I/O on my own terms. * */ #include #include #include #ifndef _WIN32 #include #endif // _WIN32 #include #include /** * Translates an integer into a string. * @param val The value to translate. * @param buf The return parameter. */ static void bc_file_ultoa(unsigned long long val, char buf[BC_FILE_ULL_LENGTH]) { char buf2[BC_FILE_ULL_LENGTH]; size_t i, len; // We need to make sure the entire thing is zeroed. memset(buf2, 0, BC_FILE_ULL_LENGTH); // The i = 1 is to ensure that there is a null byte at the end. for (i = 1; val; ++i) { unsigned long long mod = val % 10; buf2[i] = ((char) mod) + '0'; val /= 10; } len = i; // Since buf2 is reversed, reverse it into buf. for (i = 0; i < len; ++i) buf[i] = buf2[len - i - 1]; } /** * Output to the file directly. * @param fd The file descriptor. * @param buf The buffer of data to output. * @param n The number of bytes to output. * @return A status indicating error or success. We could have a fatal I/O * error or EOF. */ static BcStatus bc_file_output(int fd, const char *buf, size_t n) { size_t bytes = 0; sig_atomic_t lock; BC_SIG_TRYLOCK(lock); // While the number of bytes written is less than intended... while (bytes < n) { // Write. ssize_t written = write(fd, buf + bytes, n - bytes); // Check for error and return, if any. - if (BC_ERR(written == -1)) + if (BC_ERR(written == -1)) { + + BC_SIG_TRYUNLOCK(lock); + return errno == EPIPE ? BC_STATUS_EOF : BC_STATUS_ERROR_FATAL; + } bytes += (size_t) written; } BC_SIG_TRYUNLOCK(lock); return BC_STATUS_SUCCESS; } BcStatus bc_file_flushErr(BcFile *restrict f, BcFlushType type) { BcStatus s; + BC_SIG_ASSERT_LOCKED; + // If there is stuff to output... if (f->len) { #if BC_ENABLE_HISTORY // If history is enabled... if (BC_TTY) { // If we have been told to save the extras, and there *are* // extras... if (f->buf[f->len - 1] != '\n' && (type == BC_FLUSH_SAVE_EXTRAS_CLEAR || type == BC_FLUSH_SAVE_EXTRAS_NO_CLEAR)) { size_t i; // Look for the last newline. for (i = f->len - 2; i < f->len && f->buf[i] != '\n'; --i); i += 1; // Save the extras. bc_vec_string(&vm.history.extras, f->len - i, f->buf + i); } // Else clear the extras if told to. else if (type >= BC_FLUSH_NO_EXTRAS_CLEAR) { bc_vec_popAll(&vm.history.extras); } } #endif // BC_ENABLE_HISTORY // Actually output. s = bc_file_output(f->fd, f->buf, f->len); f->len = 0; } else s = BC_STATUS_SUCCESS; return s; } void bc_file_flush(BcFile *restrict f, BcFlushType type) { - BcStatus s = bc_file_flushErr(f, type); + BcStatus s; + sig_atomic_t lock; + + BC_SIG_TRYLOCK(lock); + + s = bc_file_flushErr(f, type); // If we have an error... if (BC_ERR(s)) { // For EOF, set it and jump. if (s == BC_STATUS_EOF) { vm.status = (sig_atomic_t) s; + BC_SIG_TRYUNLOCK(lock); BC_JMP; } // Blow up on fatal error. Okay, not blow up, just quit. else bc_vm_fatalError(BC_ERR_FATAL_IO_ERR); } + + BC_SIG_TRYUNLOCK(lock); } void bc_file_write(BcFile *restrict f, BcFlushType type, const char *buf, size_t n) { + sig_atomic_t lock; + + BC_SIG_TRYLOCK(lock); + // If we have enough to flush, do it. if (n > f->cap - f->len) { bc_file_flush(f, type); assert(!f->len); } // If the output is large enough to flush by itself, just output it. // Otherwise, put it into the buffer. if (BC_UNLIKELY(n > f->cap - f->len)) bc_file_output(f->fd, buf, n); else { memcpy(f->buf + f->len, buf, n); f->len += n; } + + BC_SIG_TRYUNLOCK(lock); } void bc_file_printf(BcFile *restrict f, const char *fmt, ...) { va_list args; + sig_atomic_t lock; + + BC_SIG_TRYLOCK(lock); va_start(args, fmt); bc_file_vprintf(f, fmt, args); va_end(args); + + BC_SIG_TRYUNLOCK(lock); } void bc_file_vprintf(BcFile *restrict f, const char *fmt, va_list args) { char *percent; const char *ptr = fmt; char buf[BC_FILE_ULL_LENGTH]; + BC_SIG_ASSERT_LOCKED; + // This is a poor man's printf(). While I could look up algorithms to make // it as fast as possible, and should when I write the standard library for // a new language, for bc, outputting is not the bottleneck. So we cheese it // for now. // Find each percent sign. while ((percent = strchr(ptr, '%')) != NULL) { char c; // If the percent sign is not where we are, write what's inbetween to // the buffer. if (percent != ptr) { size_t len = (size_t) (percent - ptr); bc_file_write(f, bc_flush_none, ptr, len); } c = percent[1]; // We only parse some format specifiers, the ones bc uses. If you add // more, you need to make sure to add them here. if (c == 'c') { uchar uc = (uchar) va_arg(args, int); bc_file_putchar(f, bc_flush_none, uc); } else if (c == 's') { char *s = va_arg(args, char*); bc_file_puts(f, bc_flush_none, s); } #if BC_DEBUG_CODE // We only print signed integers in debug code. else if (c == 'd') { int d = va_arg(args, int); // Take care of negative. Let's not worry about overflow. if (d < 0) { bc_file_putchar(f, bc_flush_none, '-'); d = -d; } // Either print 0 or translate and print. if (!d) bc_file_putchar(f, bc_flush_none, '0'); else { bc_file_ultoa((unsigned long long) d, buf); bc_file_puts(f, bc_flush_none, buf); } } #endif // BC_DEBUG_CODE else { unsigned long long ull; // These are the ones that it expects from here. Fortunately, all of // these are unsigned types, so they can use the same code, more or // less. assert((c == 'l' || c == 'z') && percent[2] == 'u'); if (c == 'z') ull = (unsigned long long) va_arg(args, size_t); else ull = (unsigned long long) va_arg(args, unsigned long); // Either print 0 or translate and print. if (!ull) bc_file_putchar(f, bc_flush_none, '0'); else { bc_file_ultoa(ull, buf); bc_file_puts(f, bc_flush_none, buf); } } // Increment to the next spot after the specifier. ptr = percent + 2 + (c == 'l' || c == 'z'); } // If we get here, there are no more percent signs, so we just output // whatever is left. if (ptr[0]) bc_file_puts(f, bc_flush_none, ptr); } void bc_file_puts(BcFile *restrict f, BcFlushType type, const char *str) { bc_file_write(f, type, str, strlen(str)); } void bc_file_putchar(BcFile *restrict f, BcFlushType type, uchar c) { + sig_atomic_t lock; + + BC_SIG_TRYLOCK(lock); + if (f->len == f->cap) bc_file_flush(f, type); assert(f->len < f->cap); f->buf[f->len] = (char) c; f->len += 1; + + BC_SIG_TRYUNLOCK(lock); } void bc_file_init(BcFile *f, int fd, char *buf, size_t cap) { BC_SIG_ASSERT_LOCKED; f->fd = fd; f->buf = buf; f->len = 0; f->cap = cap; } void bc_file_free(BcFile *f) { BC_SIG_ASSERT_LOCKED; bc_file_flush(f, bc_flush_none); } diff --git a/contrib/bc/src/history.c b/contrib/bc/src/history.c index b5ba0758075c..9f158413efc2 100644 --- a/contrib/bc/src/history.c +++ b/contrib/bc/src/history.c @@ -1,1765 +1,1818 @@ /* * ***************************************************************************** * * SPDX-License-Identifier: BSD-2-Clause * * Copyright (c) 2018-2021 Gavin D. Howard and contributors. * * Redistribution and use in source and binary forms, with or without * modification, are permitted provided that the following conditions are met: * * * Redistributions of source code must retain the above copyright notice, this * list of conditions and the following disclaimer. * * * Redistributions in binary form must reproduce the above copyright notice, * this list of conditions and the following disclaimer in the documentation * and/or other materials provided with the distribution. * * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE * POSSIBILITY OF SUCH DAMAGE. * * ***************************************************************************** * * Adapted from the following: * * linenoise.c -- guerrilla line editing library against the idea that a * line editing lib needs to be 20,000 lines of C code. * * You can find the original source code at: * http://github.com/antirez/linenoise * * You can find the fork that this code is based on at: * https://github.com/rain-1/linenoise-mob * * ------------------------------------------------------------------------ * * This code is also under the following license: * * Copyright (c) 2010-2016, Salvatore Sanfilippo * Copyright (c) 2010-2013, Pieter Noordhuis * * Redistribution and use in source and binary forms, with or without * modification, are permitted provided that the following conditions are * met: * * * Redistributions of source code must retain the above copyright * notice, this list of conditions and the following disclaimer. * * * Redistributions in binary form must reproduce the above copyright * notice, this list of conditions and the following disclaimer in the * documentation and/or other materials provided with the distribution. * * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT * HOLDER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. * * ------------------------------------------------------------------------ * * Does a number of crazy assumptions that happen to be true in 99.9999% of * the 2010 UNIX computers around. * * References: * - http://invisible-island.net/xterm/ctlseqs/ctlseqs.html * - http://www.3waylabs.com/nw/WWW/products/wizcon/vt220.html * * Todo list: * - Filter bogus Ctrl+ combinations. * - Win32 support * * Bloat: * - History search like Ctrl+r in readline? * * List of escape sequences used by this program, we do everything just * with three sequences. In order to be so cheap we may have some * flickering effect with some slow terminal, but the lesser sequences * the more compatible. * * EL (Erase Line) * Sequence: ESC [ n K * Effect: if n is 0 or missing, clear from cursor to end of line * Effect: if n is 1, clear from beginning of line to cursor * Effect: if n is 2, clear entire line * * CUF (CUrsor Forward) * Sequence: ESC [ n C * Effect: moves cursor forward n chars * * CUB (CUrsor Backward) * Sequence: ESC [ n D * Effect: moves cursor backward n chars * * The following is used to get the terminal width if getting * the width with the TIOCGWINSZ ioctl fails * * DSR (Device Status Report) * Sequence: ESC [ 6 n * Effect: reports the current cusor position as ESC [ n ; m R * where n is the row and m is the column * * When multi line mode is enabled, we also use two additional escape * sequences. However multi line editing is disabled by default. * * CUU (CUrsor Up) * Sequence: ESC [ n A * Effect: moves cursor up of n chars. * * CUD (CUrsor Down) * Sequence: ESC [ n B * Effect: moves cursor down of n chars. * * When bc_history_clearScreen() is called, two additional escape sequences * are used in order to clear the screen and position the cursor at home * position. * * CUP (CUrsor Position) * Sequence: ESC [ H * Effect: moves the cursor to upper left corner * * ED (Erase Display) * Sequence: ESC [ 2 J * Effect: clear the whole screen * * ***************************************************************************** * * Code for line history. * */ #if BC_ENABLE_HISTORY #include #include #include #include #include #include #include #include #ifndef _WIN32 #include #include #include #include #include #endif // _WIN32 #include #include #include #include #include #include #if BC_DEBUG_CODE /// A file for outputting to when debugging. BcFile bc_history_debug_fp; /// A buffer for the above file. char *bc_history_debug_buf; #endif // BC_DEBUG_CODE /** * Checks if the code is a wide character. * @param cp The codepoint to check. * @return True if @a cp is a wide character, false otherwise. */ static bool bc_history_wchar(uint32_t cp) { size_t i; for (i = 0; i < bc_history_wchars_len; ++i) { // Ranges are listed in ascending order. Therefore, once the // whole range is higher than the codepoint we're testing, the // codepoint won't be found in any remaining range => bail early. if (bc_history_wchars[i][0] > cp) return false; // Test this range. if (bc_history_wchars[i][0] <= cp && cp <= bc_history_wchars[i][1]) return true; } return false; } /** * Checks if the code is a combining character. * @param cp The codepoint to check. * @return True if @a cp is a combining character, false otherwise. */ static bool bc_history_comboChar(uint32_t cp) { size_t i; for (i = 0; i < bc_history_combo_chars_len; ++i) { // Combining chars are listed in ascending order, so once we pass // the codepoint of interest, we know it's not a combining char. if (bc_history_combo_chars[i] > cp) return false; if (bc_history_combo_chars[i] == cp) return true; } return false; } /** * Gets the length of previous UTF8 character. * @param buf The buffer of characters. * @param pos The index into the buffer. */ static size_t bc_history_prevCharLen(const char *buf, size_t pos) { size_t end = pos; for (pos -= 1; pos < end && (buf[pos] & 0xC0) == 0x80; --pos); return end - (pos >= end ? 0 : pos); } /** * Converts UTF-8 to a Unicode code point. * @param s The string. * @param len The length of the string. * @param cp An out parameter for the codepoint. * @return The number of bytes eaten by the codepoint. */ static size_t bc_history_codePoint(const char *s, size_t len, uint32_t *cp) { if (len) { uchar byte = (uchar) s[0]; // This is literally the UTF-8 decoding algorithm. Look that up if you // don't understand this. if ((byte & 0x80) == 0) { *cp = byte; return 1; } else if ((byte & 0xE0) == 0xC0) { if (len >= 2) { *cp = (((uint32_t) (s[0] & 0x1F)) << 6) | ((uint32_t) (s[1] & 0x3F)); return 2; } } else if ((byte & 0xF0) == 0xE0) { if (len >= 3) { *cp = (((uint32_t) (s[0] & 0x0F)) << 12) | (((uint32_t) (s[1] & 0x3F)) << 6) | ((uint32_t) (s[2] & 0x3F)); return 3; } } else if ((byte & 0xF8) == 0xF0) { if (len >= 4) { *cp = (((uint32_t) (s[0] & 0x07)) << 18) | (((uint32_t) (s[1] & 0x3F)) << 12) | (((uint32_t) (s[2] & 0x3F)) << 6) | ((uint32_t) (s[3] & 0x3F)); return 4; } } else { *cp = 0xFFFD; return 1; } } *cp = 0; return 1; } /** * Gets the length of next grapheme. * @param buf The buffer. * @param buf_len The length of the buffer. * @param pos The index into the buffer. * @param col_len An out parameter for the length of the grapheme on screen. * @return The number of bytes in the grapheme. */ static size_t bc_history_nextLen(const char *buf, size_t buf_len, size_t pos, size_t *col_len) { uint32_t cp; size_t beg = pos; size_t len = bc_history_codePoint(buf + pos, buf_len - pos, &cp); if (bc_history_comboChar(cp)) { BC_UNREACHABLE if (col_len != NULL) *col_len = 0; return 0; } // Store the width of the character on screen. if (col_len != NULL) *col_len = bc_history_wchar(cp) ? 2 : 1; pos += len; // Find the first non-combining character. while (pos < buf_len) { len = bc_history_codePoint(buf + pos, buf_len - pos, &cp); if (!bc_history_comboChar(cp)) return pos - beg; pos += len; } return pos - beg; } /** * Gets the length of previous grapheme. * @param buf The buffer. * @param pos The index into the buffer. * @return The number of bytes in the grapheme. */ static size_t bc_history_prevLen(const char *buf, size_t pos) { size_t end = pos; // Find the first non-combining character. while (pos > 0) { uint32_t cp; size_t len = bc_history_prevCharLen(buf, pos); pos -= len; bc_history_codePoint(buf + pos, len, &cp); // The original linenoise-mob had an extra parameter col_len, like // bc_history_nextLen(), which, if not NULL, was set in this if // statement. However, we always passed NULL, so just skip that. if (!bc_history_comboChar(cp)) return end - pos; } BC_UNREACHABLE return 0; } /** * Reads @a n characters from stdin. * @param buf The buffer to read into. The caller is responsible for making * sure this is big enough for @a n. * @param n The number of characters to read. * @return The number of characters read or less than 0 on error. */ static ssize_t bc_history_read(char *buf, size_t n) { ssize_t ret; - BC_SIG_LOCK; + BC_SIG_ASSERT_LOCKED; #ifndef _WIN32 do { // We don't care about being interrupted. ret = read(STDIN_FILENO, buf, n); } while (ret == EINTR); #else // _WIN32 bool good; DWORD read; HANDLE hn = GetStdHandle(STD_INPUT_HANDLE); good = ReadConsole(hn, buf, (DWORD) n, &read, NULL); ret = (read != n) ? -1 : 1; #endif // _WIN32 - BC_SIG_UNLOCK; - return ret; } /** * Reads a Unicode code point into a buffer. * @param buf The buffer to read into. * @param buf_len The length of the buffer. * @param cp An out parameter for the codepoint. * @param nread An out parameter for the number of bytes read. * @return BC_STATUS_EOF or BC_STATUS_SUCCESS. */ static BcStatus bc_history_readCode(char *buf, size_t buf_len, uint32_t *cp, size_t *nread) { ssize_t n; assert(buf_len >= 1); + BC_SIG_LOCK; + // Read a byte. n = bc_history_read(buf, 1); + + BC_SIG_UNLOCK; + if (BC_ERR(n <= 0)) goto err; // Get the byte. uchar byte = ((uchar*) buf)[0]; // Once again, this is the UTF-8 decoding algorithm, but it has reads // instead of actual decoding. if ((byte & 0x80) != 0) { if ((byte & 0xE0) == 0xC0) { assert(buf_len >= 2); + BC_SIG_LOCK; + n = bc_history_read(buf + 1, 1); + BC_SIG_UNLOCK; + if (BC_ERR(n <= 0)) goto err; } else if ((byte & 0xF0) == 0xE0) { assert(buf_len >= 3); + BC_SIG_LOCK; + n = bc_history_read(buf + 1, 2); + BC_SIG_UNLOCK; + if (BC_ERR(n <= 0)) goto err; } else if ((byte & 0xF8) == 0xF0) { assert(buf_len >= 3); + BC_SIG_LOCK; + n = bc_history_read(buf + 1, 3); + BC_SIG_UNLOCK; + if (BC_ERR(n <= 0)) goto err; } else { n = -1; goto err; } } // Convert to the codepoint. *nread = bc_history_codePoint(buf, buf_len, cp); return BC_STATUS_SUCCESS; err: // If we get here, we either had a fatal error of EOF. if (BC_ERR(n < 0)) bc_vm_fatalError(BC_ERR_FATAL_IO_ERR); else *nread = (size_t) n; return BC_STATUS_EOF; } /** * Gets the column length from beginning of buffer to current byte position. * @param buf The buffer. * @param buf_len The length of the buffer. * @param pos The index into the buffer. * @return The number of columns between the beginning of @a buffer to * @a pos. */ static size_t bc_history_colPos(const char *buf, size_t buf_len, size_t pos) { size_t ret = 0, off = 0; // While we haven't reached the offset, get the length of the next grapheme. while (off < pos && off < buf_len) { size_t col_len, len; len = bc_history_nextLen(buf, buf_len, off, &col_len); off += len; ret += col_len; } return ret; } /** * Returns true if the terminal name is in the list of terminals we know are * not able to understand basic escape sequences. * @return True if the terminal is a bad terminal. */ static inline bool bc_history_isBadTerm(void) { size_t i; bool ret = false; char *term = bc_vm_getenv("TERM"); if (term == NULL) return false; for (i = 0; !ret && bc_history_bad_terms[i]; ++i) ret = (!strcasecmp(term, bc_history_bad_terms[i])); bc_vm_getenvFree(term); return ret; } /** * Enables raw mode (1960's black magic). * @param h The history data. */ static void bc_history_enableRaw(BcHistory *h) { // I don't do anything for Windows because in Windows, you set their // equivalent of raw mode and leave it, so I do it in bc_history_init(). #ifndef _WIN32 struct termios raw; int err; assert(BC_TTYIN); if (h->rawMode) return; BC_SIG_LOCK; if (BC_ERR(tcgetattr(STDIN_FILENO, &h->orig_termios) == -1)) bc_vm_fatalError(BC_ERR_FATAL_IO_ERR); BC_SIG_UNLOCK; // Modify the original mode. raw = h->orig_termios; // Input modes: no break, no CR to NL, no parity check, no strip char, // no start/stop output control. raw.c_iflag &= (unsigned int) (~(BRKINT | ICRNL | INPCK | ISTRIP | IXON)); // Control modes: set 8 bit chars. raw.c_cflag |= (CS8); // Local modes - choing off, canonical off, no extended functions, // no signal chars (^Z,^C). raw.c_lflag &= (unsigned int) (~(ECHO | ICANON | IEXTEN | ISIG)); // Control chars - set return condition: min number of bytes and timer. // We want read to give every single byte, w/o timeout (1 byte, no timer). raw.c_cc[VMIN] = 1; raw.c_cc[VTIME] = 0; BC_SIG_LOCK; // Put terminal in raw mode after flushing. do { err = tcsetattr(STDIN_FILENO, TCSAFLUSH, &raw); } while (BC_ERR(err < 0) && errno == EINTR); BC_SIG_UNLOCK; if (BC_ERR(err < 0)) bc_vm_fatalError(BC_ERR_FATAL_IO_ERR); #endif // _WIN32 h->rawMode = true; } /** * Disables raw mode. * @param h The history data. */ static void bc_history_disableRaw(BcHistory *h) { sig_atomic_t lock; if (!h->rawMode) return; BC_SIG_TRYLOCK(lock); #ifndef _WIN32 if (BC_ERR(tcsetattr(STDIN_FILENO, TCSAFLUSH, &h->orig_termios) != -1)) h->rawMode = false; #endif // _WIN32 BC_SIG_TRYUNLOCK(lock); } /** * Uses the ESC [6n escape sequence to query the horizontal cursor position * and return it. On error -1 is returned, on success the position of the * cursor. * @return The horizontal cursor position. */ static size_t bc_history_cursorPos(void) { char buf[BC_HIST_SEQ_SIZE]; char *ptr, *ptr2; size_t cols, rows, i; + BC_SIG_ASSERT_LOCKED; + // Report cursor location. bc_file_write(&vm.fout, bc_flush_none, "\x1b[6n", 4); bc_file_flush(&vm.fout, bc_flush_none); // Read the response: ESC [ rows ; cols R. for (i = 0; i < sizeof(buf) - 1; ++i) { if (bc_history_read(buf + i, 1) != 1 || buf[i] == 'R') break; } buf[i] = '\0'; // This is basically an error; we didn't get what we were expecting. if (BC_ERR(buf[0] != BC_ACTION_ESC || buf[1] != '[')) return SIZE_MAX; // Parse the rows. ptr = buf + 2; rows = strtoul(ptr, &ptr2, 10); // Here we also didn't get what we were expecting. if (BC_ERR(!rows || ptr2[0] != ';')) return SIZE_MAX; // Parse the columns. ptr = ptr2 + 1; cols = strtoul(ptr, NULL, 10); if (BC_ERR(!cols)) return SIZE_MAX; return cols <= UINT16_MAX ? cols : 0; } /** * Tries to get the number of columns in the current terminal, or assume 80 * if it fails. * @return The number of columns in the terminal. */ static size_t bc_history_columns(void) { #ifndef _WIN32 struct winsize ws; int ret; - BC_SIG_LOCK; - ret = ioctl(vm.fout.fd, TIOCGWINSZ, &ws); - BC_SIG_UNLOCK; - if (BC_ERR(ret == -1 || !ws.ws_col)) { // Calling ioctl() failed. Try to query the terminal itself. size_t start, cols; // Get the initial position so we can restore it later. start = bc_history_cursorPos(); if (BC_ERR(start == SIZE_MAX)) return BC_HIST_DEF_COLS; // Go to right margin and get position. bc_file_write(&vm.fout, bc_flush_none, "\x1b[999C", 6); bc_file_flush(&vm.fout, bc_flush_none); cols = bc_history_cursorPos(); if (BC_ERR(cols == SIZE_MAX)) return BC_HIST_DEF_COLS; // Restore position. if (cols > start) { bc_file_printf(&vm.fout, "\x1b[%zuD", cols - start); bc_file_flush(&vm.fout, bc_flush_none); } return cols; } return ws.ws_col; #else // _WIN32 CONSOLE_SCREEN_BUFFER_INFO csbi; if (!GetConsoleScreenBufferInfo(GetStdHandle(STD_OUTPUT_HANDLE), &csbi)) return 80; return ((size_t) (csbi.srWindow.Right)) - csbi.srWindow.Left + 1; #endif // _WIN32 } /** * Gets the column length of prompt text. This is probably unnecessary because * the prompts that I use are ASCII, but I kept it just in case. * @param prompt The prompt. * @param plen The length of the prompt. * @return The column length of the prompt. */ static size_t bc_history_promptColLen(const char *prompt, size_t plen) { char buf[BC_HIST_MAX_LINE + 1]; size_t buf_len = 0, off = 0; // The original linenoise-mob checked for ANSI escapes here on the prompt. I // know the prompts do not have ANSI escapes. I deleted the code. while (off < plen) buf[buf_len++] = prompt[off++]; return bc_history_colPos(buf, buf_len, buf_len); } /** * Rewrites the currently edited line accordingly to the buffer content, * cursor position, and number of columns of the terminal. * @param h The history data. */ static void bc_history_refresh(BcHistory *h) { char* buf = h->buf.v; size_t colpos, len = BC_HIST_BUF_LEN(h), pos = h->pos, extras_len = 0; + BC_SIG_ASSERT_LOCKED; + bc_file_flush(&vm.fout, bc_flush_none); // Get to the prompt column position from the left. while(h->pcol + bc_history_colPos(buf, len, pos) >= h->cols) { size_t chlen = bc_history_nextLen(buf, len, 0, NULL); buf += chlen; len -= chlen; pos -= chlen; } // Get to the prompt column position from the right. while (h->pcol + bc_history_colPos(buf, len, len) > h->cols) len -= bc_history_prevLen(buf, len); // Cursor to left edge. bc_file_write(&vm.fout, bc_flush_none, "\r", 1); // Take the extra stuff into account. This is where history makes sure to // preserve stuff that was printed without a newline. if (h->extras.len > 1) { extras_len = h->extras.len - 1; bc_vec_grow(&h->buf, extras_len); len += extras_len; pos += extras_len; bc_file_write(&vm.fout, bc_flush_none, h->extras.v, extras_len); } // Write the prompt, if desired. if (BC_PROMPT) bc_file_write(&vm.fout, bc_flush_none, h->prompt, h->plen); bc_file_write(&vm.fout, bc_flush_none, h->buf.v, len - extras_len); // Erase to right. bc_file_write(&vm.fout, bc_flush_none, "\x1b[0K", 4); // We need to be sure to grow this. if (pos >= h->buf.len - extras_len) bc_vec_grow(&h->buf, pos + extras_len); // Move cursor to original position. colpos = bc_history_colPos(h->buf.v, len - extras_len, pos) + h->pcol; // Set the cursor position again. if (colpos) bc_file_printf(&vm.fout, "\r\x1b[%zuC", colpos); bc_file_flush(&vm.fout, bc_flush_none); } /** * Inserts the character(s) 'c' at cursor current position. * @param h The history data. * @param cbuf The character buffer to copy from. * @param clen The number of characters to copy. */ static void bc_history_edit_insert(BcHistory *h, const char *cbuf, size_t clen) { + BC_SIG_ASSERT_LOCKED; + bc_vec_grow(&h->buf, clen); // If we are at the end of the line... if (h->pos == BC_HIST_BUF_LEN(h)) { size_t colpos = 0, len; // Copy into the buffer. memcpy(bc_vec_item(&h->buf, h->pos), cbuf, clen); // Adjust the buffer. h->pos += clen; h->buf.len += clen - 1; bc_vec_pushByte(&h->buf, '\0'); // Set the length and column position. len = BC_HIST_BUF_LEN(h) + h->extras.len - 1; colpos = bc_history_promptColLen(h->prompt, h->plen); colpos += bc_history_colPos(h->buf.v, len, len); // Do we have the trivial case? if (colpos < h->cols) { // Avoid a full update of the line in the trivial case. bc_file_write(&vm.fout, bc_flush_none, cbuf, clen); bc_file_flush(&vm.fout, bc_flush_none); } else bc_history_refresh(h); } else { // Amount that we need to move. size_t amt = BC_HIST_BUF_LEN(h) - h->pos; // Move the stuff. memmove(h->buf.v + h->pos + clen, h->buf.v + h->pos, amt); memcpy(h->buf.v + h->pos, cbuf, clen); // Adjust the buffer. h->pos += clen; h->buf.len += clen; h->buf.v[BC_HIST_BUF_LEN(h)] = '\0'; bc_history_refresh(h); } } /** * Moves the cursor to the left. * @param h The history data. */ static void bc_history_edit_left(BcHistory *h) { + BC_SIG_ASSERT_LOCKED; + // Stop at the left end. if (h->pos <= 0) return; h->pos -= bc_history_prevLen(h->buf.v, h->pos); bc_history_refresh(h); } /** * Moves the cursor to the right. * @param h The history data. */ static void bc_history_edit_right(BcHistory *h) { + BC_SIG_ASSERT_LOCKED; + // Stop at the right end. if (h->pos == BC_HIST_BUF_LEN(h)) return; h->pos += bc_history_nextLen(h->buf.v, BC_HIST_BUF_LEN(h), h->pos, NULL); bc_history_refresh(h); } /** * Moves the cursor to the end of the current word. * @param h The history data. */ static void bc_history_edit_wordEnd(BcHistory *h) { size_t len = BC_HIST_BUF_LEN(h); + BC_SIG_ASSERT_LOCKED; + // Don't overflow. if (!len || h->pos >= len) return; // Find the word, then find the end of it. while (h->pos < len && isspace(h->buf.v[h->pos])) h->pos += 1; while (h->pos < len && !isspace(h->buf.v[h->pos])) h->pos += 1; bc_history_refresh(h); } /** * Moves the cursor to the start of the current word. * @param h The history data. */ static void bc_history_edit_wordStart(BcHistory *h) { size_t len = BC_HIST_BUF_LEN(h); + BC_SIG_ASSERT_LOCKED; + // Stop with no data. if (!len) return; // Find the word, the find the beginning of the word. while (h->pos > 0 && isspace(h->buf.v[h->pos - 1])) h->pos -= 1; while (h->pos > 0 && !isspace(h->buf.v[h->pos - 1])) h->pos -= 1; bc_history_refresh(h); } /** * Moves the cursor to the start of the line. * @param h The history data. */ static void bc_history_edit_home(BcHistory *h) { + BC_SIG_ASSERT_LOCKED; + // Stop at the beginning. if (!h->pos) return; h->pos = 0; bc_history_refresh(h); } /** * Moves the cursor to the end of the line. * @param h The history data. */ static void bc_history_edit_end(BcHistory *h) { + BC_SIG_ASSERT_LOCKED; + // Stop at the end of the line. if (h->pos == BC_HIST_BUF_LEN(h)) return; h->pos = BC_HIST_BUF_LEN(h); bc_history_refresh(h); } /** * Substitutes the currently edited line with the next or previous history * entry as specified by 'dir' (direction). * @param h The history data. * @param dir The direction to substitute; true means previous, false next. */ static void bc_history_edit_next(BcHistory *h, bool dir) { const char *dup, *str; + BC_SIG_ASSERT_LOCKED; + // Stop if there is no history. if (h->history.len <= 1) return; - BC_SIG_LOCK; - // Duplicate the buffer. if (h->buf.v[0]) dup = bc_vm_strdup(h->buf.v); else dup = ""; // Update the current history entry before overwriting it with the next one. bc_vec_replaceAt(&h->history, h->history.len - 1 - h->idx, &dup); - BC_SIG_UNLOCK; - // Show the new entry. h->idx += (dir == BC_HIST_PREV ? 1 : SIZE_MAX); // Se the index appropriately at the ends. if (h->idx == SIZE_MAX) { h->idx = 0; return; } else if (h->idx >= h->history.len) { h->idx = h->history.len - 1; return; } // Get the string. str = *((char**) bc_vec_item(&h->history, h->history.len - 1 - h->idx)); bc_vec_string(&h->buf, strlen(str), str); assert(h->buf.len > 0); // Set the position at the end. h->pos = BC_HIST_BUF_LEN(h); bc_history_refresh(h); } /** * Deletes the character at the right of the cursor without altering the cursor * position. Basically, this is what happens with the "Delete" keyboard key. * @param h The history data. */ static void bc_history_edit_delete(BcHistory *h) { size_t chlen, len = BC_HIST_BUF_LEN(h); + BC_SIG_ASSERT_LOCKED; + // If there is no character, skip. if (!len || h->pos >= len) return; // Get the length of the character. chlen = bc_history_nextLen(h->buf.v, len, h->pos, NULL); // Move characters after it into its place. memmove(h->buf.v + h->pos, h->buf.v + h->pos + chlen, len - h->pos - chlen); // Make the buffer valid again. h->buf.len -= chlen; h->buf.v[BC_HIST_BUF_LEN(h)] = '\0'; bc_history_refresh(h); } /** * Deletes the character to the left of the cursor and moves the cursor back one * space. Basically, this is what happens with the "Backspace" keyboard key. * @param h The history data. */ static void bc_history_edit_backspace(BcHistory *h) { size_t chlen, len = BC_HIST_BUF_LEN(h); + BC_SIG_ASSERT_LOCKED; + // If there are no characters, skip. if (!h->pos || !len) return; // Get the length of the previous character. chlen = bc_history_prevLen(h->buf.v, h->pos); // Move everything back one. memmove(h->buf.v + h->pos - chlen, h->buf.v + h->pos, len - h->pos); // Make the buffer valid again. h->pos -= chlen; h->buf.len -= chlen; h->buf.v[BC_HIST_BUF_LEN(h)] = '\0'; bc_history_refresh(h); } /** * Deletes the previous word, maintaining the cursor at the start of the * current word. * @param h The history data. */ static void bc_history_edit_deletePrevWord(BcHistory *h) { size_t diff, old_pos = h->pos; + BC_SIG_ASSERT_LOCKED; + // If at the beginning of the line, skip. if (!old_pos) return; // Find the word, then the beginning of the word. while (h->pos > 0 && isspace(h->buf.v[h->pos - 1])) --h->pos; while (h->pos > 0 && !isspace(h->buf.v[h->pos - 1])) --h->pos; // Get the difference in position. diff = old_pos - h->pos; // Move the data back. memmove(h->buf.v + h->pos, h->buf.v + old_pos, BC_HIST_BUF_LEN(h) - old_pos + 1); // Make the buffer valid again. h->buf.len -= diff; bc_history_refresh(h); } /** * Deletes the next word, maintaining the cursor at the same position. * @param h The history data. */ static void bc_history_edit_deleteNextWord(BcHistory *h) { size_t next_end = h->pos, len = BC_HIST_BUF_LEN(h); + BC_SIG_ASSERT_LOCKED; + // If at the end of the line, skip. if (next_end == len) return; // Find the word, then the end of the word. while (next_end < len && isspace(h->buf.v[next_end])) ++next_end; while (next_end < len && !isspace(h->buf.v[next_end])) ++next_end; // Move the stuff into position. memmove(h->buf.v + h->pos, h->buf.v + next_end, len - next_end); // Make the buffer valid again. h->buf.len -= next_end - h->pos; bc_history_refresh(h); } /** * Swaps two characters, the one under the cursor and the one to the left. * @param h The history data. */ static void bc_history_swap(BcHistory *h) { size_t pcl, ncl; char auxb[5]; + BC_SIG_ASSERT_LOCKED; + // Get the length of the previous and next characters. pcl = bc_history_prevLen(h->buf.v, h->pos); ncl = bc_history_nextLen(h->buf.v, BC_HIST_BUF_LEN(h), h->pos, NULL); // To perform a swap we need: // * Nonzero char length to the left. // * To not be at the end of the line. if (pcl && h->pos != BC_HIST_BUF_LEN(h) && pcl < 5 && ncl < 5) { // Swap. memcpy(auxb, h->buf.v + h->pos - pcl, pcl); memcpy(h->buf.v + h->pos - pcl, h->buf.v + h->pos, ncl); memcpy(h->buf.v + h->pos - pcl + ncl, auxb, pcl); // Reset the position. h->pos += ((~pcl) + 1) + ncl; bc_history_refresh(h); } } /** * Raises the specified signal. This is a convenience function. * @param h The history data. * @param sig The signal to raise. */ static void bc_history_raise(BcHistory *h, int sig) { // We really don't want to be in raw mode when longjmp()'s are flying. bc_history_disableRaw(h); raise(sig); } /** * Handles escape sequences. This function will make sense if you know VT100 * escape codes; otherwise, it will be confusing. * @param h The history data. */ static void bc_history_escape(BcHistory *h) { char c, seq[3]; + BC_SIG_ASSERT_LOCKED; + // Read a character into seq. if (BC_ERR(BC_HIST_READ(seq, 1))) return; c = seq[0]; // ESC ? sequences. if (c != '[' && c != 'O') { if (c == 'f') bc_history_edit_wordEnd(h); else if (c == 'b') bc_history_edit_wordStart(h); else if (c == 'd') bc_history_edit_deleteNextWord(h); } else { // Read a character into seq. if (BC_ERR(BC_HIST_READ(seq + 1, 1))) bc_vm_fatalError(BC_ERR_FATAL_IO_ERR); // ESC [ sequences. if (c == '[') { c = seq[1]; if (c >= '0' && c <= '9') { // Extended escape, read additional byte. if (BC_ERR(BC_HIST_READ(seq + 2, 1))) bc_vm_fatalError(BC_ERR_FATAL_IO_ERR); if (seq[2] == '~' && c == '3') bc_history_edit_delete(h); else if(seq[2] == ';') { // Read two characters into seq. if (BC_ERR(BC_HIST_READ(seq, 2))) bc_vm_fatalError(BC_ERR_FATAL_IO_ERR); if (seq[0] != '5') return; else if (seq[1] == 'C') bc_history_edit_wordEnd(h); else if (seq[1] == 'D') bc_history_edit_wordStart(h); } } else { switch(c) { // Up. case 'A': { bc_history_edit_next(h, BC_HIST_PREV); break; } // Down. case 'B': { bc_history_edit_next(h, BC_HIST_NEXT); break; } // Right. case 'C': { bc_history_edit_right(h); break; } // Left. case 'D': { bc_history_edit_left(h); break; } // Home. case 'H': case '1': { bc_history_edit_home(h); break; } // End. case 'F': case '4': { bc_history_edit_end(h); break; } case 'd': { bc_history_edit_deleteNextWord(h); break; } } } } // ESC O sequences. else { switch (seq[1]) { case 'A': { bc_history_edit_next(h, BC_HIST_PREV); break; } case 'B': { bc_history_edit_next(h, BC_HIST_NEXT); break; } case 'C': { bc_history_edit_right(h); break; } case 'D': { bc_history_edit_left(h); break; } case 'F': { bc_history_edit_end(h); break; } case 'H': { bc_history_edit_home(h); break; } } } } } /** * Adds a line to the history. * @param h The history data. * @param line The line to add. */ static void bc_history_add(BcHistory *h, char *line) { + BC_SIG_ASSERT_LOCKED; + // If there is something already there... if (h->history.len) { // Get the previous. char *s = *((char**) bc_vec_item_rev(&h->history, 0)); // Check for, and discard, duplicates. if (!strcmp(s, line)) { - - BC_SIG_LOCK; - free(line); - - BC_SIG_UNLOCK; - return; } } bc_vec_push(&h->history, &line); } /** * Adds an empty line to the history. This is separate from bc_history_add() * because we don't want it allocating. * @param h The history data. */ static void bc_history_add_empty(BcHistory *h) { + BC_SIG_ASSERT_LOCKED; + const char *line = ""; // If there is something already there... if (h->history.len) { // Get the previous. char *s = *((char**) bc_vec_item_rev(&h->history, 0)); // Check for, and discard, duplicates. if (!s[0]) return; } bc_vec_push(&h->history, &line); } /** * Resets the history state to nothing. * @param h The history data. */ static void bc_history_reset(BcHistory *h) { + BC_SIG_ASSERT_LOCKED; + h->oldcolpos = h->pos = h->idx = 0; h->cols = bc_history_columns(); // The latest history entry is always our current buffer, that // initially is just an empty string. bc_history_add_empty(h); // Buffer starts empty. bc_vec_empty(&h->buf); } /** * Prints a control character. * @param h The history data. * @param c The control character to print. */ static void bc_history_printCtrl(BcHistory *h, unsigned int c) { char str[3] = "^A"; const char newline[2] = "\n"; + BC_SIG_ASSERT_LOCKED; + // Set the correct character. str[1] = (char) (c + 'A' - BC_ACTION_CTRL_A); // Concatenate the string. bc_vec_concat(&h->buf, str); bc_history_refresh(h); // Pop the string. bc_vec_npop(&h->buf, sizeof(str)); bc_vec_pushByte(&h->buf, '\0'); #ifndef _WIN32 if (c != BC_ACTION_CTRL_C && c != BC_ACTION_CTRL_D) #endif // _WIN32 { // We sometimes want to print a newline; for the times we don't; it's // because newlines are taken care of elsewhere. bc_file_write(&vm.fout, bc_flush_none, newline, sizeof(newline) - 1); bc_history_refresh(h); } } /** * Edits a line of history. This function is the core of the line editing * capability of bc history. It expects 'fd' to be already in "raw mode" so that * every key pressed will be returned ASAP to read(). * @param h The history data. * @param prompt The prompt. * @return BC_STATUS_SUCCESS or BC_STATUS_EOF. */ static BcStatus bc_history_edit(BcHistory *h, const char *prompt) { + BC_SIG_LOCK; + bc_history_reset(h); // Don't write the saved output the first time. This is because it has // already been written to output. In other words, don't uncomment the // line below or add anything like it. // bc_file_write(&vm.fout, bc_flush_none, h->extras.v, h->extras.len - 1); // Write the prompt if desired. if (BC_PROMPT) { h->prompt = prompt; h->plen = strlen(prompt); h->pcol = bc_history_promptColLen(prompt, h->plen); bc_file_write(&vm.fout, bc_flush_none, prompt, h->plen); bc_file_flush(&vm.fout, bc_flush_none); } // This is the input loop. for (;;) { BcStatus s; char cbuf[32]; unsigned int c = 0; size_t nread = 0; + BC_SIG_UNLOCK; + // Read a code. s = bc_history_readCode(cbuf, sizeof(cbuf), &c, &nread); if (BC_ERR(s)) return s; + BC_SIG_LOCK; + switch (c) { case BC_ACTION_LINE_FEED: case BC_ACTION_ENTER: { // Return the line. bc_vec_pop(&h->history); + BC_SIG_UNLOCK; return s; } case BC_ACTION_TAB: { // My tab handling is dumb; it just prints 8 spaces every time. memcpy(cbuf, bc_history_tab, bc_history_tab_len + 1); bc_history_edit_insert(h, cbuf, bc_history_tab_len); break; } #ifndef _WIN32 case BC_ACTION_CTRL_C: { bc_history_printCtrl(h, c); // Quit if the user wants it. if (!BC_SIGINT) { vm.status = BC_STATUS_QUIT; + BC_SIG_UNLOCK; BC_JMP; } // Print the ready message. bc_file_write(&vm.fout, bc_flush_none, vm.sigmsg, vm.siglen); bc_file_write(&vm.fout, bc_flush_none, bc_program_ready_msg, bc_program_ready_msg_len); bc_history_reset(h); bc_history_refresh(h); break; } #endif // _WIN32 case BC_ACTION_BACKSPACE: case BC_ACTION_CTRL_H: { bc_history_edit_backspace(h); break; } #ifndef _WIN32 // Act as end-of-file. case BC_ACTION_CTRL_D: { bc_history_printCtrl(h, c); + BC_SIG_UNLOCK; return BC_STATUS_EOF; } #endif // _WIN32 // Swaps current character with previous. case BC_ACTION_CTRL_T: { bc_history_swap(h); break; } case BC_ACTION_CTRL_B: { bc_history_edit_left(h); break; } case BC_ACTION_CTRL_F: { bc_history_edit_right(h); break; } case BC_ACTION_CTRL_P: { bc_history_edit_next(h, BC_HIST_PREV); break; } case BC_ACTION_CTRL_N: { bc_history_edit_next(h, BC_HIST_NEXT); break; } case BC_ACTION_ESC: { bc_history_escape(h); break; } // Delete the whole line. case BC_ACTION_CTRL_U: { bc_vec_string(&h->buf, 0, ""); h->pos = 0; bc_history_refresh(h); break; } // Delete from current to end of line. case BC_ACTION_CTRL_K: { bc_vec_npop(&h->buf, h->buf.len - h->pos); bc_vec_pushByte(&h->buf, '\0'); bc_history_refresh(h); break; } // Go to the start of the line. case BC_ACTION_CTRL_A: { bc_history_edit_home(h); break; } // Go to the end of the line. case BC_ACTION_CTRL_E: { bc_history_edit_end(h); break; } // Clear screen. case BC_ACTION_CTRL_L: { bc_file_write(&vm.fout, bc_flush_none, "\x1b[H\x1b[2J", 7); bc_history_refresh(h); break; } // Delete previous word. case BC_ACTION_CTRL_W: { bc_history_edit_deletePrevWord(h); break; } default: { // If we have a control character, print it and raise signals as // needed. if ((c >= BC_ACTION_CTRL_A && c <= BC_ACTION_CTRL_Z) || c == BC_ACTION_CTRL_BSLASH) { bc_history_printCtrl(h, c); #ifndef _WIN32 if (c == BC_ACTION_CTRL_Z) bc_history_raise(h, SIGTSTP); if (c == BC_ACTION_CTRL_S) bc_history_raise(h, SIGSTOP); if (c == BC_ACTION_CTRL_BSLASH) bc_history_raise(h, SIGQUIT); #else // _WIN32 vm.status = BC_STATUS_QUIT; + BC_SIG_UNLOCK; BC_JMP; #endif // _WIN32 } // Otherwise, just insert. else bc_history_edit_insert(h, cbuf, nread); break; } } } + BC_SIG_UNLOCK; + return BC_STATUS_SUCCESS; } /** * Returns true if stdin has more data. This is for multi-line pasting, and it * does not work on Windows. * @param h The history data. */ static inline bool bc_history_stdinHasData(BcHistory *h) { #ifndef _WIN32 int n; return pselect(1, &h->rdset, NULL, NULL, &h->ts, &h->sigmask) > 0 || (ioctl(STDIN_FILENO, FIONREAD, &n) >= 0 && n > 0); #else // _WIN32 return false; #endif // _WIN32 } BcStatus bc_history_line(BcHistory *h, BcVec *vec, const char *prompt) { BcStatus s; char* line; assert(vm.fout.len == 0); bc_history_enableRaw(h); do { // Do the edit. s = bc_history_edit(h, prompt); // Print a newline and flush. bc_file_write(&vm.fout, bc_flush_none, "\n", 1); bc_file_flush(&vm.fout, bc_flush_none); + BC_SIG_LOCK; + // If we actually have data... if (h->buf.v[0]) { - BC_SIG_LOCK; - // Duplicate it. line = bc_vm_strdup(h->buf.v); - BC_SIG_UNLOCK; - // Store it. bc_history_add(h, line); } // Add an empty string. else bc_history_add_empty(h); + BC_SIG_UNLOCK; + // Concatenate the line to the return vector. bc_vec_concat(vec, h->buf.v); bc_vec_concat(vec, "\n"); } while (!s && bc_history_stdinHasData(h)); assert(!s || s == BC_STATUS_EOF); bc_history_disableRaw(h); return s; } void bc_history_string_free(void *str) { char *s = *((char**) str); BC_SIG_ASSERT_LOCKED; if (s[0]) free(s); } void bc_history_init(BcHistory *h) { #ifdef _WIN32 HANDLE out, in; #endif // _WIN32 BC_SIG_ASSERT_LOCKED; h->rawMode = false; h->badTerm = bc_history_isBadTerm(); #ifdef _WIN32 h->orig_in = 0; h->orig_out = 0; in = GetStdHandle(STD_INPUT_HANDLE); out = GetStdHandle(STD_OUTPUT_HANDLE); if (!h->badTerm) { SetConsoleCP(CP_UTF8); SetConsoleOutputCP(CP_UTF8); if (!GetConsoleMode(in, &h->orig_in) || !GetConsoleMode(out, &h->orig_out)) { h->badTerm = true; return; } else { DWORD reqOut = ENABLE_VIRTUAL_TERMINAL_PROCESSING | DISABLE_NEWLINE_AUTO_RETURN; DWORD reqIn = ENABLE_VIRTUAL_TERMINAL_INPUT; if (!SetConsoleMode(in, h->orig_in | reqIn) || !SetConsoleMode(out, h->orig_out | reqOut)) { h->badTerm = true; } } } #endif // _WIN32 bc_vec_init(&h->buf, sizeof(char), BC_DTOR_NONE); bc_vec_init(&h->history, sizeof(char*), BC_DTOR_HISTORY_STRING); bc_vec_init(&h->extras, sizeof(char), BC_DTOR_NONE); #ifndef _WIN32 FD_ZERO(&h->rdset); FD_SET(STDIN_FILENO, &h->rdset); h->ts.tv_sec = 0; h->ts.tv_nsec = 0; sigemptyset(&h->sigmask); sigaddset(&h->sigmask, SIGINT); #endif // _WIN32 } void bc_history_free(BcHistory *h) { BC_SIG_ASSERT_LOCKED; #ifndef _WIN32 bc_history_disableRaw(h); #else // _WIN32 SetConsoleMode(GetStdHandle(STD_INPUT_HANDLE), h->orig_in); SetConsoleMode(GetStdHandle(STD_OUTPUT_HANDLE), h->orig_out); #endif // _WIN32 #ifndef NDEBUG bc_vec_free(&h->buf); bc_vec_free(&h->history); bc_vec_free(&h->extras); #endif // NDEBUG } #if BC_DEBUG_CODE /** * Prints scan codes. This special mode is used by bc history in order to print * scan codes on screen for debugging / development purposes. * @param h The history data. */ void bc_history_printKeyCodes(BcHistory *h) { char quit[4]; bc_vm_printf("Linenoise key codes debugging mode.\n" "Press keys to see scan codes. " "Type 'quit' at any time to exit.\n"); bc_history_enableRaw(h); memset(quit, ' ', 4); while(true) { char c; ssize_t nread; nread = bc_history_read(&c, 1); if (nread <= 0) continue; // Shift string to left. memmove(quit, quit + 1, sizeof(quit) - 1); // Insert current char on the right. quit[sizeof(quit) - 1] = c; if (!memcmp(quit, "quit", sizeof(quit))) break; bc_vm_printf("'%c' %lu (type quit to exit)\n", isprint(c) ? c : '?', (unsigned long) c); // Go left edge manually, we are in raw mode. bc_vm_putchar('\r', bc_flush_none); bc_file_flush(&vm.fout, bc_flush_none); } bc_history_disableRaw(h); } #endif // BC_DEBUG_CODE #endif // BC_ENABLE_HISTORY diff --git a/contrib/bc/src/lex.c b/contrib/bc/src/lex.c index f8b32451aef7..51e9f31bfa11 100644 --- a/contrib/bc/src/lex.c +++ b/contrib/bc/src/lex.c @@ -1,311 +1,326 @@ /* * ***************************************************************************** * * SPDX-License-Identifier: BSD-2-Clause * * Copyright (c) 2018-2021 Gavin D. Howard and contributors. * * Redistribution and use in source and binary forms, with or without * modification, are permitted provided that the following conditions are met: * * * Redistributions of source code must retain the above copyright notice, this * list of conditions and the following disclaimer. * * * Redistributions in binary form must reproduce the above copyright notice, * this list of conditions and the following disclaimer in the documentation * and/or other materials provided with the distribution. * * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE * POSSIBILITY OF SUCH DAMAGE. * * ***************************************************************************** * * Common code for the lexers. * */ #include #include #include #include #include #include #include void bc_lex_invalidChar(BcLex *l, char c) { l->t = BC_LEX_INVALID; bc_lex_verr(l, BC_ERR_PARSE_CHAR, c); } void bc_lex_lineComment(BcLex *l) { l->t = BC_LEX_WHITESPACE; while (l->i < l->len && l->buf[l->i] != '\n') l->i += 1; } void bc_lex_comment(BcLex *l) { size_t i, nlines = 0; const char *buf; bool end = false, got_more; char c; l->i += 1; l->t = BC_LEX_WHITESPACE; // This loop is complex because it might need to request more data from // stdin if the comment is not ended. This loop is taken until the comment // is finished or we have EOF. do { buf = l->buf; got_more = false; // If we are in stdin mode, the buffer must be the one used for stdin. assert(!vm.is_stdin || buf == vm.buffer.v); // Find the end of the comment. for (i = l->i; !end; i += !end) { // While we don't have an asterisk, eat, but increment nlines. for (; (c = buf[i]) && c != '*'; ++i) nlines += (c == '\n'); // If this is true, we need to request more data. if (BC_ERR(!c || buf[i + 1] == '\0')) { // Read more. if (!vm.eof && l->is_stdin) got_more = bc_lex_readLine(l); break; } // If this turns true, we found the end. Yay! end = (buf[i + 1] == '/'); } } while (got_more && !end); // If we didn't find the end, barf. if (!end) { l->i = i; bc_lex_err(l, BC_ERR_PARSE_COMMENT); } l->i = i + 2; l->line += nlines; } void bc_lex_whitespace(BcLex *l) { char c; l->t = BC_LEX_WHITESPACE; // Eat. We don't eat newlines because they can be special. for (c = l->buf[l->i]; c != '\n' && isspace(c); c = l->buf[++l->i]); } void bc_lex_commonTokens(BcLex *l, char c) { if (!c) l->t = BC_LEX_EOF; else if (c == '\n') l->t = BC_LEX_NLINE; else bc_lex_whitespace(l); } /** * Parses a number. * @param l The lexer. * @param start The start character. * @param int_only Whether this function should only look for an integer. This * is used to implement the exponent of scientific notation. */ static size_t bc_lex_num(BcLex *l, char start, bool int_only) { const char *buf = l->buf + l->i; size_t i; char c; bool last_pt, pt = (start == '.'); // This loop looks complex. It is not. It is asking if the character is not // a nul byte and it if it a valid num character based on what we have found // thus far, or whether it is a backslash followed by a newline. I can do // i+1 on the buffer because the buffer must have a nul byte. for (i = 0; (c = buf[i]) && (BC_LEX_NUM_CHAR(c, pt, int_only) || (c == '\\' && buf[i + 1] == '\n')); ++i) { // I don't need to test that the next character is a newline because // the loop condition above ensures that. if (c == '\\') { i += 2; // Make sure to eat whitespace at the beginning of the line. while(isspace(buf[i]) && buf[i] != '\n') i += 1; c = buf[i]; // If the next character is not a number character, bail. if (!BC_LEX_NUM_CHAR(c, pt, int_only)) break; } // Did we find the radix point? last_pt = (c == '.'); // If we did, and we already have one, then break because it's not part // of this number. if (pt && last_pt) break; // Set whether we have found a radix point. pt = pt || last_pt; bc_vec_push(&l->str, &c); } return i; } void bc_lex_number(BcLex *l, char start) { l->t = BC_LEX_NUMBER; // Make sure the string is clear. bc_vec_popAll(&l->str); bc_vec_push(&l->str, &start); // Parse the number. l->i += bc_lex_num(l, start, false); #if BC_ENABLE_EXTRA_MATH { char c = l->buf[l->i]; // Do we have a number in scientific notation? if (c == 'e') { #if BC_ENABLED // Barf for POSIX. if (BC_IS_POSIX) bc_lex_err(l, BC_ERR_POSIX_EXP_NUM); #endif // BC_ENABLED // Push the e. bc_vec_push(&l->str, &c); l->i += 1; c = l->buf[l->i]; // Check for negative specifically because bc_lex_num() does not. if (c == BC_LEX_NEG_CHAR) { bc_vec_push(&l->str, &c); l->i += 1; c = l->buf[l->i]; } // We must have a number character, so barf if not. if (BC_ERR(!BC_LEX_NUM_CHAR(c, false, true))) bc_lex_verr(l, BC_ERR_PARSE_CHAR, c); // Parse the exponent. l->i += bc_lex_num(l, 0, true); } } #endif // BC_ENABLE_EXTRA_MATH bc_vec_pushByte(&l->str, '\0'); } void bc_lex_name(BcLex *l) { size_t i = 0; const char *buf = l->buf + l->i - 1; char c = buf[i]; l->t = BC_LEX_NAME; // Should be obvious. It's looking for valid characters. while ((c >= 'a' && c <= 'z') || isdigit(c) || c == '_') c = buf[++i]; // Set the string to the identifier. bc_vec_string(&l->str, i, buf); // Increment the index. We minus 1 because it has already been incremented. l->i += i - 1; } void bc_lex_init(BcLex *l) { BC_SIG_ASSERT_LOCKED; assert(l != NULL); bc_vec_init(&l->str, sizeof(char), BC_DTOR_NONE); } void bc_lex_free(BcLex *l) { BC_SIG_ASSERT_LOCKED; assert(l != NULL); bc_vec_free(&l->str); } void bc_lex_file(BcLex *l, const char *file) { assert(l != NULL && file != NULL); l->line = 1; vm.file = file; } void bc_lex_next(BcLex *l) { + BC_SIG_ASSERT_LOCKED; + assert(l != NULL); l->last = l->t; // If this wasn't here, the line number would be off. l->line += (l->i != 0 && l->buf[l->i - 1] == '\n'); // If the last token was EOF, someone called this one too many times. if (BC_ERR(l->last == BC_LEX_EOF)) bc_lex_err(l, BC_ERR_PARSE_EOF); l->t = BC_LEX_EOF; // We are done if this is true. if (l->i == l->len) return; // Loop until failure or we don't have whitespace. This // is so the parser doesn't get inundated with whitespace. do { vm.next(l); } while (l->t == BC_LEX_WHITESPACE); } /** * Updates the buffer and len so that they are not invalidated when the stdin * buffer grows. * @param l The lexer. * @param text The text. * @param len The length of the text. */ static void bc_lex_fixText(BcLex *l, const char *text, size_t len) { l->buf = text; l->len = len; } bool bc_lex_readLine(BcLex *l) { - bool good = bc_vm_readLine(false); + bool good; + + // These are reversed because they should be already locked, but + // bc_vm_readLine() needs them to be unlocked. + BC_SIG_UNLOCK; + + good = bc_vm_readLine(false); + + BC_SIG_LOCK; bc_lex_fixText(l, vm.buffer.v, vm.buffer.len - 1); return good; } void bc_lex_text(BcLex *l, const char *text, bool is_stdin) { + + BC_SIG_ASSERT_LOCKED; + assert(l != NULL && text != NULL); + bc_lex_fixText(l, text, strlen(text)); l->i = 0; l->t = l->last = BC_LEX_INVALID; l->is_stdin = is_stdin; + bc_lex_next(l); } diff --git a/contrib/bc/src/library.c b/contrib/bc/src/library.c index e0bd3ee98b85..a9246a025206 100644 --- a/contrib/bc/src/library.c +++ b/contrib/bc/src/library.c @@ -1,1281 +1,1287 @@ /* * ***************************************************************************** * * SPDX-License-Identifier: BSD-2-Clause * * Copyright (c) 2018-2021 Gavin D. Howard and contributors. * * Redistribution and use in source and binary forms, with or without * modification, are permitted provided that the following conditions are met: * * * Redistributions of source code must retain the above copyright notice, this * list of conditions and the following disclaimer. * * * Redistributions in binary form must reproduce the above copyright notice, * this list of conditions and the following disclaimer in the documentation * and/or other materials provided with the distribution. * * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE * POSSIBILITY OF SUCH DAMAGE. * * ***************************************************************************** * * The public functions for libbc. * */ #if BC_ENABLE_LIBRARY #include #include #include #include #include #include #include // The asserts in this file are important to testing; in many cases, the test // would not work without the asserts, so don't remove them without reason. // // Also, there are many uses of bc_num_clear() here; that is because numbers are // being reused, and a clean slate is required. // // Also, there are a bunch of BC_UNSETJMP and BC_SETJMP_LOCKED() between calls // to bc_num_init(). That is because locals are being initialized, and unlike bc // proper, this code cannot assume that allocation failures are fatal. So we // have to reset the jumps every time to ensure that the locals will be correct // after jumping. void bcl_handleSignal(void) { // Signal already in flight, or bc is not executing. if (vm.sig || !vm.running) return; vm.sig = 1; assert(vm.jmp_bufs.len); if (!vm.sig_lock) BC_JMP; } bool bcl_running(void) { return vm.running != 0; } BclError bcl_init(void) { BclError e = BCL_ERROR_NONE; + BC_SIG_LOCK; + vm.refs += 1; - if (vm.refs > 1) return e; + if (vm.refs > 1) { + BC_SIG_UNLOCK; + return e; + } // Setting these to NULL ensures that if an error occurs, we only free what // is necessary. vm.ctxts.v = NULL; vm.jmp_bufs.v = NULL; vm.out.v = NULL; vm.abrt = false; - BC_SIG_LOCK; - // The jmp_bufs always has to be initialized first. bc_vec_init(&vm.jmp_bufs, sizeof(sigjmp_buf), BC_DTOR_NONE); BC_FUNC_HEADER_INIT(err); bc_vm_init(); bc_vec_init(&vm.ctxts, sizeof(BclContext), BC_DTOR_NONE); bc_vec_init(&vm.out, sizeof(uchar), BC_DTOR_NONE); // We need to seed this in case /dev/random and /dev/urandm don't work. srand((unsigned int) time(NULL)); bc_rand_init(&vm.rng); err: // This is why we had to set them to NULL. if (BC_ERR(vm.err)) { if (vm.out.v != NULL) bc_vec_free(&vm.out); if (vm.jmp_bufs.v != NULL) bc_vec_free(&vm.jmp_bufs); if (vm.ctxts.v != NULL) bc_vec_free(&vm.ctxts); } BC_FUNC_FOOTER_UNLOCK(e); assert(!vm.running && !vm.sig && !vm.sig_lock); return e; } BclError bcl_pushContext(BclContext ctxt) { BclError e = BCL_ERROR_NONE; BC_FUNC_HEADER_LOCK(err); bc_vec_push(&vm.ctxts, &ctxt); err: BC_FUNC_FOOTER_UNLOCK(e); return e; } void bcl_popContext(void) { if (vm.ctxts.len) bc_vec_pop(&vm.ctxts); } BclContext bcl_context(void) { if (!vm.ctxts.len) return NULL; return *((BclContext*) bc_vec_top(&vm.ctxts)); } void bcl_free(void) { size_t i; - vm.refs -= 1; + BC_SIG_LOCK; - if (vm.refs) return; + vm.refs -= 1; - BC_SIG_LOCK; + if (vm.refs) { + BC_SIG_UNLOCK; + return; + } bc_rand_free(&vm.rng); bc_vec_free(&vm.out); for (i = 0; i < vm.ctxts.len; ++i) { BclContext ctxt = *((BclContext*) bc_vec_item(&vm.ctxts, i)); bcl_ctxt_free(ctxt); } bc_vec_free(&vm.ctxts); bc_vm_atexit(); BC_SIG_UNLOCK; memset(&vm, 0, sizeof(BcVm)); assert(!vm.running && !vm.sig && !vm.sig_lock); } void bcl_gc(void) { BC_SIG_LOCK; bc_vm_freeTemps(); BC_SIG_UNLOCK; } bool bcl_abortOnFatalError(void) { return vm.abrt; } void bcl_setAbortOnFatalError(bool abrt) { vm.abrt = abrt; } bool bcl_leadingZeroes(void) { return vm.leading_zeroes; } void bcl_setLeadingZeroes(bool leadingZeroes) { vm.leading_zeroes = leadingZeroes; } BclContext bcl_ctxt_create(void) { BclContext ctxt = NULL; BC_FUNC_HEADER_LOCK(err); // We want the context to be free of any interference of other parties, so // malloc() is appropriate here. ctxt = bc_vm_malloc(sizeof(BclCtxt)); bc_vec_init(&ctxt->nums, sizeof(BcNum), BC_DTOR_BCL_NUM); bc_vec_init(&ctxt->free_nums, sizeof(BclNumber), BC_DTOR_NONE); ctxt->scale = 0; ctxt->ibase = 10; ctxt->obase= 10; err: if (BC_ERR(vm.err && ctxt != NULL)) { if (ctxt->nums.v != NULL) bc_vec_free(&ctxt->nums); free(ctxt); ctxt = NULL; } BC_FUNC_FOOTER_NO_ERR; assert(!vm.running && !vm.sig && !vm.sig_lock); return ctxt; } void bcl_ctxt_free(BclContext ctxt) { BC_SIG_LOCK; bc_vec_free(&ctxt->free_nums); bc_vec_free(&ctxt->nums); free(ctxt); BC_SIG_UNLOCK; } void bcl_ctxt_freeNums(BclContext ctxt) { bc_vec_popAll(&ctxt->nums); bc_vec_popAll(&ctxt->free_nums); } size_t bcl_ctxt_scale(BclContext ctxt) { return ctxt->scale; } void bcl_ctxt_setScale(BclContext ctxt, size_t scale) { ctxt->scale = scale; } size_t bcl_ctxt_ibase(BclContext ctxt) { return ctxt->ibase; } void bcl_ctxt_setIbase(BclContext ctxt, size_t ibase) { if (ibase < BC_NUM_MIN_BASE) ibase = BC_NUM_MIN_BASE; else if (ibase > BC_NUM_MAX_IBASE) ibase = BC_NUM_MAX_IBASE; ctxt->ibase = ibase; } size_t bcl_ctxt_obase(BclContext ctxt) { return ctxt->obase; } void bcl_ctxt_setObase(BclContext ctxt, size_t obase) { ctxt->obase = obase; } BclError bcl_err(BclNumber n) { BclContext ctxt; BC_CHECK_CTXT_ERR(ctxt); // Errors are encoded as (0 - error_code). If the index is in that range, it // is an encoded error. if (n.i >= ctxt->nums.len) { if (n.i > 0 - (size_t) BCL_ERROR_NELEMS) return (BclError) (0 - n.i); else return BCL_ERROR_INVALID_NUM; } else return BCL_ERROR_NONE; } /** * Inserts a BcNum into a context's list of numbers. * @param ctxt The context to insert into. * @param n The BcNum to insert. * @return The resulting BclNumber from the insert. */ static BclNumber bcl_num_insert(BclContext ctxt, BcNum *restrict n) { BclNumber idx; // If there is a free spot... if (ctxt->free_nums.len) { BcNum *ptr; // Get the index of the free spot and remove it. idx = *((BclNumber*) bc_vec_top(&ctxt->free_nums)); bc_vec_pop(&ctxt->free_nums); // Copy the number into the spot. ptr = bc_vec_item(&ctxt->nums, idx.i); memcpy(ptr, n, sizeof(BcNum)); } else { // Just push the number onto the vector. idx.i = ctxt->nums.len; bc_vec_push(&ctxt->nums, n); } assert(!vm.running && !vm.sig && !vm.sig_lock); return idx; } BclNumber bcl_num_create(void) { BclError e = BCL_ERROR_NONE; BcNum n; BclNumber idx; BclContext ctxt; BC_CHECK_CTXT(ctxt); BC_FUNC_HEADER_LOCK(err); bc_vec_grow(&ctxt->nums, 1); bc_num_init(&n, BC_NUM_DEF_SIZE); err: BC_FUNC_FOOTER_UNLOCK(e); BC_MAYBE_SETUP(ctxt, e, n, idx); assert(!vm.running && !vm.sig && !vm.sig_lock); return idx; } /** * Destructs a number and marks its spot as free. * @param ctxt The context. * @param n The index of the number. * @param num The number to destroy. */ static void bcl_num_dtor(BclContext ctxt, BclNumber n, BcNum *restrict num) { BC_SIG_ASSERT_LOCKED; assert(num != NULL && num->num != NULL); bcl_num_destruct(num); bc_vec_push(&ctxt->free_nums, &n); } void bcl_num_free(BclNumber n) { BcNum *num; BclContext ctxt; BC_CHECK_CTXT_ASSERT(ctxt); BC_SIG_LOCK; assert(n.i < ctxt->nums.len); num = BC_NUM(ctxt, n); bcl_num_dtor(ctxt, n, num); BC_SIG_UNLOCK; } BclError bcl_copy(BclNumber d, BclNumber s) { BclError e = BCL_ERROR_NONE; BcNum *dest, *src; BclContext ctxt; BC_CHECK_CTXT_ERR(ctxt); BC_FUNC_HEADER_LOCK(err); assert(d.i < ctxt->nums.len && s.i < ctxt->nums.len); dest = BC_NUM(ctxt, d); src = BC_NUM(ctxt, s); assert(dest != NULL && src != NULL); assert(dest->num != NULL && src->num != NULL); bc_num_copy(dest, src); err: BC_FUNC_FOOTER_UNLOCK(e); assert(!vm.running && !vm.sig && !vm.sig_lock); return e; } BclNumber bcl_dup(BclNumber s) { BclError e = BCL_ERROR_NONE; BcNum *src, dest; BclNumber idx; BclContext ctxt; BC_CHECK_CTXT(ctxt); BC_FUNC_HEADER_LOCK(err); bc_vec_grow(&ctxt->nums, 1); assert(s.i < ctxt->nums.len); src = BC_NUM(ctxt, s); assert(src != NULL && src->num != NULL); // Copy the number. bc_num_clear(&dest); bc_num_createCopy(&dest, src); err: BC_FUNC_FOOTER_UNLOCK(e); BC_MAYBE_SETUP(ctxt, e, dest, idx); assert(!vm.running && !vm.sig && !vm.sig_lock); return idx; } void bcl_num_destruct(void *num) { BcNum *n = (BcNum*) num; assert(n != NULL); if (n->num == NULL) return; bc_num_free(num); bc_num_clear(num); } bool bcl_num_neg(BclNumber n) { BcNum *num; BclContext ctxt; BC_CHECK_CTXT_ASSERT(ctxt); assert(n.i < ctxt->nums.len); num = BC_NUM(ctxt, n); assert(num != NULL && num->num != NULL); return BC_NUM_NEG(num) != 0; } void bcl_num_setNeg(BclNumber n, bool neg) { BcNum *num; BclContext ctxt; BC_CHECK_CTXT_ASSERT(ctxt); assert(n.i < ctxt->nums.len); num = BC_NUM(ctxt, n); assert(num != NULL && num->num != NULL); num->rdx = BC_NUM_NEG_VAL(num, neg); } size_t bcl_num_scale(BclNumber n) { BcNum *num; BclContext ctxt; BC_CHECK_CTXT_ASSERT(ctxt); assert(n.i < ctxt->nums.len); num = BC_NUM(ctxt, n); assert(num != NULL && num->num != NULL); return bc_num_scale(num); } BclError bcl_num_setScale(BclNumber n, size_t scale) { BclError e = BCL_ERROR_NONE; BcNum *nptr; BclContext ctxt; BC_CHECK_CTXT_ERR(ctxt); BC_CHECK_NUM_ERR(ctxt, n); BC_FUNC_HEADER(err); assert(n.i < ctxt->nums.len); nptr = BC_NUM(ctxt, n); assert(nptr != NULL && nptr->num != NULL); if (scale > nptr->scale) bc_num_extend(nptr, scale - nptr->scale); else if (scale < nptr->scale) bc_num_truncate(nptr, nptr->scale - scale); err: BC_SIG_MAYLOCK; BC_FUNC_FOOTER(e); assert(!vm.running && !vm.sig && !vm.sig_lock); return e; } size_t bcl_num_len(BclNumber n) { BcNum *num; BclContext ctxt; BC_CHECK_CTXT_ASSERT(ctxt); assert(n.i < ctxt->nums.len); num = BC_NUM(ctxt, n); assert(num != NULL && num->num != NULL); return bc_num_len(num); } BclError bcl_bigdig(BclNumber n, BclBigDig *result) { BclError e = BCL_ERROR_NONE; BcNum *num; BclContext ctxt; BC_CHECK_CTXT_ERR(ctxt); BC_FUNC_HEADER_LOCK(err); assert(n.i < ctxt->nums.len); assert(result != NULL); num = BC_NUM(ctxt, n); assert(num != NULL && num->num != NULL); *result = bc_num_bigdig(num); err: bcl_num_dtor(ctxt, n, num); BC_FUNC_FOOTER_UNLOCK(e); assert(!vm.running && !vm.sig && !vm.sig_lock); return e; } BclNumber bcl_bigdig2num(BclBigDig val) { BclError e = BCL_ERROR_NONE; BcNum n; BclNumber idx; BclContext ctxt; BC_CHECK_CTXT(ctxt); BC_FUNC_HEADER_LOCK(err); bc_vec_grow(&ctxt->nums, 1); bc_num_createFromBigdig(&n, val); err: BC_FUNC_FOOTER_UNLOCK(e); BC_MAYBE_SETUP(ctxt, e, n, idx); assert(!vm.running && !vm.sig && !vm.sig_lock); return idx; } /** * Sets up and executes a binary operator operation. * @param a The first operand. * @param b The second operand. * @param op The operation. * @param req The function to get the size of the result for preallocation. * @return The result of the operation. */ static BclNumber bcl_binary(BclNumber a, BclNumber b, const BcNumBinaryOp op, const BcNumBinaryOpReq req) { BclError e = BCL_ERROR_NONE; BcNum *aptr, *bptr; BcNum c; BclNumber idx; BclContext ctxt; BC_CHECK_CTXT(ctxt); BC_CHECK_NUM(ctxt, a); BC_CHECK_NUM(ctxt, b); BC_FUNC_HEADER_LOCK(err); bc_vec_grow(&ctxt->nums, 1); assert(a.i < ctxt->nums.len && b.i < ctxt->nums.len); aptr = BC_NUM(ctxt, a); bptr = BC_NUM(ctxt, b); assert(aptr != NULL && bptr != NULL); assert(aptr->num != NULL && bptr->num != NULL); // Clear and initialize the result. bc_num_clear(&c); bc_num_init(&c, req(aptr, bptr, ctxt->scale)); BC_SIG_UNLOCK; op(aptr, bptr, &c, ctxt->scale); err: BC_SIG_MAYLOCK; // Eat the operands. bcl_num_dtor(ctxt, a, aptr); if (b.i != a.i) bcl_num_dtor(ctxt, b, bptr); BC_FUNC_FOOTER(e); BC_MAYBE_SETUP(ctxt, e, c, idx); assert(!vm.running && !vm.sig && !vm.sig_lock); return idx; } BclNumber bcl_add(BclNumber a, BclNumber b) { return bcl_binary(a, b, bc_num_add, bc_num_addReq); } BclNumber bcl_sub(BclNumber a, BclNumber b) { return bcl_binary(a, b, bc_num_sub, bc_num_addReq); } BclNumber bcl_mul(BclNumber a, BclNumber b) { return bcl_binary(a, b, bc_num_mul, bc_num_mulReq); } BclNumber bcl_div(BclNumber a, BclNumber b) { return bcl_binary(a, b, bc_num_div, bc_num_divReq); } BclNumber bcl_mod(BclNumber a, BclNumber b) { return bcl_binary(a, b, bc_num_mod, bc_num_divReq); } BclNumber bcl_pow(BclNumber a, BclNumber b) { return bcl_binary(a, b, bc_num_pow, bc_num_powReq); } BclNumber bcl_lshift(BclNumber a, BclNumber b) { return bcl_binary(a, b, bc_num_lshift, bc_num_placesReq); } BclNumber bcl_rshift(BclNumber a, BclNumber b) { return bcl_binary(a, b, bc_num_rshift, bc_num_placesReq); } BclNumber bcl_sqrt(BclNumber a) { BclError e = BCL_ERROR_NONE; BcNum *aptr; BcNum b; BclNumber idx; BclContext ctxt; BC_CHECK_CTXT(ctxt); BC_CHECK_NUM(ctxt, a); BC_FUNC_HEADER(err); bc_vec_grow(&ctxt->nums, 1); assert(a.i < ctxt->nums.len); aptr = BC_NUM(ctxt, a); bc_num_sqrt(aptr, &b, ctxt->scale); err: BC_SIG_MAYLOCK; bcl_num_dtor(ctxt, a, aptr); BC_FUNC_FOOTER(e); BC_MAYBE_SETUP(ctxt, e, b, idx); assert(!vm.running && !vm.sig && !vm.sig_lock); return idx; } BclError bcl_divmod(BclNumber a, BclNumber b, BclNumber *c, BclNumber *d) { BclError e = BCL_ERROR_NONE; size_t req; BcNum *aptr, *bptr; BcNum cnum, dnum; BclContext ctxt; BC_CHECK_CTXT_ERR(ctxt); BC_CHECK_NUM_ERR(ctxt, a); BC_CHECK_NUM_ERR(ctxt, b); BC_FUNC_HEADER_LOCK(err); bc_vec_grow(&ctxt->nums, 2); assert(c != NULL && d != NULL); aptr = BC_NUM(ctxt, a); bptr = BC_NUM(ctxt, b); assert(aptr != NULL && bptr != NULL); assert(aptr->num != NULL && bptr->num != NULL); bc_num_clear(&cnum); bc_num_clear(&dnum); req = bc_num_divReq(aptr, bptr, ctxt->scale); // Initialize the numbers. bc_num_init(&cnum, req); BC_UNSETJMP; BC_SETJMP_LOCKED(err); bc_num_init(&dnum, req); BC_SIG_UNLOCK; bc_num_divmod(aptr, bptr, &cnum, &dnum, ctxt->scale); err: BC_SIG_MAYLOCK; // Eat the operands. bcl_num_dtor(ctxt, a, aptr); if (b.i != a.i) bcl_num_dtor(ctxt, b, bptr); // If there was an error... if (BC_ERR(vm.err)) { // Free the results. if (cnum.num != NULL) bc_num_free(&cnum); if (dnum.num != NULL) bc_num_free(&dnum); // Make sure the return values are invalid. c->i = 0 - (size_t) BCL_ERROR_INVALID_NUM; d->i = c->i; BC_FUNC_FOOTER(e); } else { BC_FUNC_FOOTER(e); // Insert the results into the context. *c = bcl_num_insert(ctxt, &cnum); *d = bcl_num_insert(ctxt, &dnum); } assert(!vm.running && !vm.sig && !vm.sig_lock); return e; } BclNumber bcl_modexp(BclNumber a, BclNumber b, BclNumber c) { BclError e = BCL_ERROR_NONE; size_t req; BcNum *aptr, *bptr, *cptr; BcNum d; BclNumber idx; BclContext ctxt; BC_CHECK_CTXT(ctxt); BC_CHECK_NUM(ctxt, a); BC_CHECK_NUM(ctxt, b); BC_CHECK_NUM(ctxt, c); BC_FUNC_HEADER_LOCK(err); bc_vec_grow(&ctxt->nums, 1); assert(a.i < ctxt->nums.len && b.i < ctxt->nums.len); assert(c.i < ctxt->nums.len); aptr = BC_NUM(ctxt, a); bptr = BC_NUM(ctxt, b); cptr = BC_NUM(ctxt, c); assert(aptr != NULL && bptr != NULL && cptr != NULL); assert(aptr->num != NULL && bptr->num != NULL && cptr->num != NULL); // Prepare the result. bc_num_clear(&d); req = bc_num_divReq(aptr, cptr, 0); // Initialize the result. bc_num_init(&d, req); BC_SIG_UNLOCK; bc_num_modexp(aptr, bptr, cptr, &d); err: BC_SIG_MAYLOCK; // Eat the operands. bcl_num_dtor(ctxt, a, aptr); if (b.i != a.i) bcl_num_dtor(ctxt, b, bptr); if (c.i != a.i && c.i != b.i) bcl_num_dtor(ctxt, c, cptr); BC_FUNC_FOOTER(e); BC_MAYBE_SETUP(ctxt, e, d, idx); assert(!vm.running && !vm.sig && !vm.sig_lock); return idx; } ssize_t bcl_cmp(BclNumber a, BclNumber b) { BcNum *aptr, *bptr; BclContext ctxt; BC_CHECK_CTXT_ASSERT(ctxt); assert(a.i < ctxt->nums.len && b.i < ctxt->nums.len); aptr = BC_NUM(ctxt, a); bptr = BC_NUM(ctxt, b); assert(aptr != NULL && bptr != NULL); assert(aptr->num != NULL && bptr->num != NULL); return bc_num_cmp(aptr, bptr); } void bcl_zero(BclNumber n) { BcNum *nptr; BclContext ctxt; BC_CHECK_CTXT_ASSERT(ctxt); assert(n.i < ctxt->nums.len); nptr = BC_NUM(ctxt, n); assert(nptr != NULL && nptr->num != NULL); bc_num_zero(nptr); } void bcl_one(BclNumber n) { BcNum *nptr; BclContext ctxt; BC_CHECK_CTXT_ASSERT(ctxt); assert(n.i < ctxt->nums.len); nptr = BC_NUM(ctxt, n); assert(nptr != NULL && nptr->num != NULL); bc_num_one(nptr); } BclNumber bcl_parse(const char *restrict val) { BclError e = BCL_ERROR_NONE; BcNum n; BclNumber idx; BclContext ctxt; bool neg; BC_CHECK_CTXT(ctxt); BC_FUNC_HEADER_LOCK(err); bc_vec_grow(&ctxt->nums, 1); assert(val != NULL); // We have to take care of negative here because bc's number parsing does // not. neg = (val[0] == '-'); if (neg) val += 1; if (!bc_num_strValid(val)) { vm.err = BCL_ERROR_PARSE_INVALID_STR; goto err; } // Clear and initialize the number. bc_num_clear(&n); bc_num_init(&n, BC_NUM_DEF_SIZE); BC_SIG_UNLOCK; bc_num_parse(&n, val, (BcBigDig) ctxt->ibase); // Set the negative. n.rdx = BC_NUM_NEG_VAL_NP(n, neg); err: BC_SIG_MAYLOCK; BC_FUNC_FOOTER(e); BC_MAYBE_SETUP(ctxt, e, n, idx); assert(!vm.running && !vm.sig && !vm.sig_lock); return idx; } char* bcl_string(BclNumber n) { BcNum *nptr; char *str = NULL; BclContext ctxt; BC_CHECK_CTXT_ASSERT(ctxt); if (BC_ERR(n.i >= ctxt->nums.len)) return str; BC_FUNC_HEADER(err); assert(n.i < ctxt->nums.len); nptr = BC_NUM(ctxt, n); assert(nptr != NULL && nptr->num != NULL); // Clear the buffer. bc_vec_popAll(&vm.out); // Print to the buffer. bc_num_print(nptr, (BcBigDig) ctxt->obase, false); bc_vec_pushByte(&vm.out, '\0'); BC_SIG_LOCK; // Just dup the string; the caller is responsible for it. str = bc_vm_strdup(vm.out.v); err: // Eat the operand. bcl_num_dtor(ctxt, n, nptr); BC_FUNC_FOOTER_NO_ERR; assert(!vm.running && !vm.sig && !vm.sig_lock); return str; } BclNumber bcl_irand(BclNumber a) { BclError e = BCL_ERROR_NONE; BcNum *aptr; BcNum b; BclNumber idx; BclContext ctxt; BC_CHECK_CTXT(ctxt); BC_CHECK_NUM(ctxt, a); BC_FUNC_HEADER_LOCK(err); bc_vec_grow(&ctxt->nums, 1); assert(a.i < ctxt->nums.len); aptr = BC_NUM(ctxt, a); assert(aptr != NULL && aptr->num != NULL); // Clear and initialize the result. bc_num_clear(&b); bc_num_init(&b, BC_NUM_DEF_SIZE); BC_SIG_UNLOCK; bc_num_irand(aptr, &b, &vm.rng); err: BC_SIG_MAYLOCK; // Eat the operand. bcl_num_dtor(ctxt, a, aptr); BC_FUNC_FOOTER(e); BC_MAYBE_SETUP(ctxt, e, b, idx); assert(!vm.running && !vm.sig && !vm.sig_lock); return idx; } /** * Helps bcl_frand(). This is separate because the error handling is easier that * way. It is also easier to do ifrand that way. * @param b The return parameter. * @param places The number of decimal places to generate. */ static void bcl_frandHelper(BcNum *restrict b, size_t places) { BcNum exp, pow, ten; BcDig exp_digs[BC_NUM_BIGDIG_LOG10]; BcDig ten_digs[BC_NUM_BIGDIG_LOG10]; // Set up temporaries. bc_num_setup(&exp, exp_digs, BC_NUM_BIGDIG_LOG10); bc_num_setup(&ten, ten_digs, BC_NUM_BIGDIG_LOG10); ten.num[0] = 10; ten.len = 1; bc_num_bigdig2num(&exp, (BcBigDig) places); // Clear the temporary that might need to grow. bc_num_clear(&pow); BC_SIG_LOCK; // Initialize the temporary that might need to grow. bc_num_init(&pow, bc_num_powReq(&ten, &exp, 0)); BC_SETJMP_LOCKED(err); BC_SIG_UNLOCK; // Generate the number. bc_num_pow(&ten, &exp, &pow, 0); bc_num_irand(&pow, b, &vm.rng); // Make the number entirely fraction. bc_num_shiftRight(b, places); err: BC_SIG_MAYLOCK; bc_num_free(&pow); BC_LONGJMP_CONT; } BclNumber bcl_frand(size_t places) { BclError e = BCL_ERROR_NONE; BcNum n; BclNumber idx; BclContext ctxt; BC_CHECK_CTXT(ctxt); BC_FUNC_HEADER_LOCK(err); bc_vec_grow(&ctxt->nums, 1); // Clear and initialize the number. bc_num_clear(&n); bc_num_init(&n, BC_NUM_DEF_SIZE); BC_SIG_UNLOCK; bcl_frandHelper(&n, places); err: BC_SIG_MAYLOCK; BC_FUNC_FOOTER(e); BC_MAYBE_SETUP(ctxt, e, n, idx); assert(!vm.running && !vm.sig && !vm.sig_lock); return idx; } /** * Helps bc_ifrand(). This is separate because error handling is easier that * way. * @param a The limit for bc_num_irand(). * @param b The return parameter. * @param places The number of decimal places to generate. */ static void bcl_ifrandHelper(BcNum *restrict a, BcNum *restrict b, size_t places) { BcNum ir, fr; // Clear the integer and fractional numbers. bc_num_clear(&ir); bc_num_clear(&fr); BC_SIG_LOCK; // Initialize the integer and fractional numbers. bc_num_init(&ir, BC_NUM_DEF_SIZE); bc_num_init(&fr, BC_NUM_DEF_SIZE); BC_SETJMP_LOCKED(err); BC_SIG_UNLOCK; bc_num_irand(a, &ir, &vm.rng); bcl_frandHelper(&fr, places); bc_num_add(&ir, &fr, b, 0); err: BC_SIG_MAYLOCK; bc_num_free(&fr); bc_num_free(&ir); BC_LONGJMP_CONT; } BclNumber bcl_ifrand(BclNumber a, size_t places) { BclError e = BCL_ERROR_NONE; BcNum *aptr; BcNum b; BclNumber idx; BclContext ctxt; BC_CHECK_CTXT(ctxt); BC_CHECK_NUM(ctxt, a); BC_FUNC_HEADER_LOCK(err); bc_vec_grow(&ctxt->nums, 1); assert(a.i < ctxt->nums.len); aptr = BC_NUM(ctxt, a); assert(aptr != NULL && aptr->num != NULL); // Clear and initialize the number. bc_num_clear(&b); bc_num_init(&b, BC_NUM_DEF_SIZE); BC_SIG_UNLOCK; bcl_ifrandHelper(aptr, &b, places); err: BC_SIG_MAYLOCK; // Eat the oprand. bcl_num_dtor(ctxt, a, aptr); BC_FUNC_FOOTER(e); BC_MAYBE_SETUP(ctxt, e, b, idx); assert(!vm.running && !vm.sig && !vm.sig_lock); return idx; } BclError bcl_rand_seedWithNum(BclNumber n) { BclError e = BCL_ERROR_NONE; BcNum *nptr; BclContext ctxt; BC_CHECK_CTXT_ERR(ctxt); BC_CHECK_NUM_ERR(ctxt, n); BC_FUNC_HEADER(err); assert(n.i < ctxt->nums.len); nptr = BC_NUM(ctxt, n); assert(nptr != NULL && nptr->num != NULL); bc_num_rng(nptr, &vm.rng); err: BC_SIG_MAYLOCK; BC_FUNC_FOOTER(e); assert(!vm.running && !vm.sig && !vm.sig_lock); return e; } BclError bcl_rand_seed(unsigned char seed[BCL_SEED_SIZE]) { BclError e = BCL_ERROR_NONE; size_t i; ulong vals[BCL_SEED_ULONGS]; BC_FUNC_HEADER(err); // Fill the array. for (i = 0; i < BCL_SEED_SIZE; ++i) { ulong val = ((ulong) seed[i]) << (((ulong) CHAR_BIT) * (i % sizeof(ulong))); vals[i / sizeof(long)] |= val; } bc_rand_seed(&vm.rng, vals[0], vals[1], vals[2], vals[3]); err: BC_SIG_MAYLOCK; BC_FUNC_FOOTER(e); return e; } void bcl_rand_reseed(void) { bc_rand_srand(bc_vec_top(&vm.rng.v)); } BclNumber bcl_rand_seed2num(void) { BclError e = BCL_ERROR_NONE; BcNum n; BclNumber idx; BclContext ctxt; BC_CHECK_CTXT(ctxt); BC_FUNC_HEADER_LOCK(err); // Clear and initialize the number. bc_num_clear(&n); bc_num_init(&n, BC_NUM_DEF_SIZE); BC_SIG_UNLOCK; bc_num_createFromRNG(&n, &vm.rng); err: BC_SIG_MAYLOCK; BC_FUNC_FOOTER(e); BC_MAYBE_SETUP(ctxt, e, n, idx); assert(!vm.running && !vm.sig && !vm.sig_lock); return idx; } BclRandInt bcl_rand_int(void) { return (BclRandInt) bc_rand_int(&vm.rng); } BclRandInt bcl_rand_bounded(BclRandInt bound) { if (bound <= 1) return 0; return (BclRandInt) bc_rand_bounded(&vm.rng, (BcRand) bound); } #endif // BC_ENABLE_LIBRARY diff --git a/contrib/bc/src/opt.c b/contrib/bc/src/opt.c index ddc78362e7b1..971e7e5f3ca5 100644 --- a/contrib/bc/src/opt.c +++ b/contrib/bc/src/opt.c @@ -1,359 +1,359 @@ /* * ***************************************************************************** * * SPDX-License-Identifier: BSD-2-Clause * * Copyright (c) 2018-2021 Gavin D. Howard and contributors. * * Redistribution and use in source and binary forms, with or without * modification, are permitted provided that the following conditions are met: * * * Redistributions of source code must retain the above copyright notice, this * list of conditions and the following disclaimer. * * * Redistributions in binary form must reproduce the above copyright notice, * this list of conditions and the following disclaimer in the documentation * and/or other materials provided with the distribution. * * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE * POSSIBILITY OF SUCH DAMAGE. * * ***************************************************************************** * * Adapted from https://github.com/skeeto/optparse * * ***************************************************************************** * * Code for getopt_long() replacement. It turns out that getopt_long() has * different behavior on different platforms. * */ #include #include #include #include #include #include #include /** * Returns true if index @a i is the end of the longopts array. * @param longopts The long options array. * @param i The index to test. * @return True if @a i is the last index, false otherwise. */ static inline bool bc_opt_longoptsEnd(const BcOptLong *longopts, size_t i) { return !longopts[i].name && !longopts[i].val; } /** * Returns the name of the long option that matches the character @a c. * @param longopts The long options array. * @param c The character to match against. * @return The name of the long option that matches @a c, or "NULL". */ static const char* bc_opt_longopt(const BcOptLong *longopts, int c) { size_t i; for (i = 0; !bc_opt_longoptsEnd(longopts, i); ++i) { if (longopts[i].val == c) return longopts[i].name; } BC_UNREACHABLE return "NULL"; } /** * Issues a fatal error for an option parsing failure. * @param err The error. * @param c The character for the failing option. * @param str Either the string for the failing option, or the invalid * option. * @param use_short True if the short option should be used for error printing, * false otherwise. */ static void bc_opt_error(BcErr err, int c, const char *str, bool use_short) { if (err == BC_ERR_FATAL_OPTION) { if (use_short) { char short_str[2]; short_str[0] = (char) c; short_str[1] = '\0'; bc_error(err, 0, short_str); } else bc_error(err, 0, str); } else bc_error(err, 0, (int) c, str); } /** * Returns the type of the long option that matches @a c. * @param longopts The long options array. * @param c The character to match against. * @return The type of the long option as an integer, or -1 if none. */ static int bc_opt_type(const BcOptLong *longopts, char c) { size_t i; if (c == ':') return -1; for (i = 0; !bc_opt_longoptsEnd(longopts, i) && longopts[i].val != c; ++i); if (bc_opt_longoptsEnd(longopts, i)) return -1; return (int) longopts[i].type; } /** * Parses a short option. * @param o The option parser. * @param longopts The long options array. * @return The character for the short option, or -1 if none left. */ static int bc_opt_parseShort(BcOpt *o, const BcOptLong *longopts) { int type; char *next; char *option = o->argv[o->optind]; int ret = -1; // Make sure to clear these. o->optopt = 0; o->optarg = NULL; // Get the next option. option += o->subopt + 1; o->optopt = option[0]; // Get the type and the next data. type = bc_opt_type(longopts, option[0]); next = o->argv[o->optind + 1]; switch (type) { case -1: case BC_OPT_BC_ONLY: case BC_OPT_DC_ONLY: { // Check for invalid option and barf if so. if (type == -1 || (type == BC_OPT_BC_ONLY && BC_IS_DC) || (type == BC_OPT_DC_ONLY && BC_IS_BC)) { char str[2] = {0, 0}; str[0] = option[0]; o->optind += 1; bc_opt_error(BC_ERR_FATAL_OPTION, option[0], str, true); } } // Fallthrough. BC_FALLTHROUGH case BC_OPT_NONE: { // If there is something else, update the suboption. if (option[1]) o->subopt += 1; else { // Go to the next argument. o->subopt = 0; o->optind += 1; } ret = (int) option[0]; break; } case BC_OPT_REQUIRED_BC_ONLY: { if (BC_IS_DC) bc_opt_error(BC_ERR_FATAL_OPTION, option[0], bc_opt_longopt(longopts, option[0]), true); } // Fallthrough BC_FALLTHROUGH case BC_OPT_REQUIRED: { // Always go to the next argument. o->subopt = 0; o->optind += 1; // Use the next characters, if they exist. if (option[1]) o->optarg = option + 1; else if (next != NULL) { // USe the next. o->optarg = next; o->optind += 1; } // No argument, barf. else bc_opt_error(BC_ERR_FATAL_OPTION_NO_ARG, option[0], bc_opt_longopt(longopts, option[0]), true); ret = (int) option[0]; break; } } return ret; } /** * Ensures that a long option argument matches a long option name, regardless of * "=" at the end. * @param name The name to match. * @param option The command-line argument. * @return True if @a option matches @a name, false otherwise. */ static bool bc_opt_longoptsMatch(const char *name, const char *option) { const char *a = option, *n = name; // Can never match a NULL name. if (name == NULL) return false; - // Loop through + // Loop through. for (; *a && *n && *a != '='; ++a, ++n) { if (*a != *n) return false; } // Ensure they both end at the same place. return (*n == '\0' && (*a == '\0' || *a == '=')); } /** * Returns a pointer to the argument of a long option, or NULL if it not in the * same argument. * @param option The option to find the argument of. * @return A pointer to the argument of the option, or NULL if none. */ static char* bc_opt_longoptsArg(char *option) { // Find the end or equals sign. for (; *option && *option != '='; ++option); if (*option == '=') return option + 1; else return NULL; } int bc_opt_parse(BcOpt *o, const BcOptLong *longopts) { size_t i; char *option; bool empty; // This just eats empty options. do { option = o->argv[o->optind]; if (option == NULL) return -1; empty = !strcmp(option, ""); o->optind += empty; } while (empty); // If the option is just a "--". if (BC_OPT_ISDASHDASH(option)) { // Consume "--". o->optind += 1; return -1; } // Parse a short option. else if (BC_OPT_ISSHORTOPT(option)) return bc_opt_parseShort(o, longopts); // If the option is not long at this point, we are done. else if (!BC_OPT_ISLONGOPT(option)) return -1; // Clear these. o->optopt = 0; o->optarg = NULL; // Skip "--" at beginning of the option. option += 2; o->optind += 1; // Loop through the valid long options. for (i = 0; !bc_opt_longoptsEnd(longopts, i); i++) { const char *name = longopts[i].name; // If we have a match... if (bc_opt_longoptsMatch(name, option)) { char *arg; // Get the option char and the argument. o->optopt = longopts[i].val; arg = bc_opt_longoptsArg(option); // Error if the option is invalid.. if ((longopts[i].type == BC_OPT_BC_ONLY && BC_IS_DC) || (longopts[i].type == BC_OPT_REQUIRED_BC_ONLY && BC_IS_DC) || (longopts[i].type == BC_OPT_DC_ONLY && BC_IS_BC)) { bc_opt_error(BC_ERR_FATAL_OPTION, o->optopt, name, false); } // Error if we have an argument and should not. if (longopts[i].type == BC_OPT_NONE && arg != NULL) { bc_opt_error(BC_ERR_FATAL_OPTION_ARG, o->optopt, name, false); } // Set the argument, or check the next argument if we don't have // one. if (arg != NULL) o->optarg = arg; else if (longopts[i].type == BC_OPT_REQUIRED || longopts[i].type == BC_OPT_REQUIRED_BC_ONLY) { // Get the next argument. o->optarg = o->argv[o->optind]; // All's good if it exists; otherwise, barf. if (o->optarg != NULL) o->optind += 1; else bc_opt_error(BC_ERR_FATAL_OPTION_NO_ARG, o->optopt, name, false); } return o->optopt; } } // If we reach this point, the option is invalid. bc_opt_error(BC_ERR_FATAL_OPTION, 0, option, false); BC_UNREACHABLE return -1; } void bc_opt_init(BcOpt *o, char *argv[]) { o->argv = argv; o->optind = 1; o->subopt = 0; o->optarg = NULL; } diff --git a/contrib/bc/src/parse.c b/contrib/bc/src/parse.c index ea4c25e8ba10..7fdfa31df4ac 100644 --- a/contrib/bc/src/parse.c +++ b/contrib/bc/src/parse.c @@ -1,251 +1,249 @@ /* * ***************************************************************************** * * SPDX-License-Identifier: BSD-2-Clause * * Copyright (c) 2018-2021 Gavin D. Howard and contributors. * * Redistribution and use in source and binary forms, with or without * modification, are permitted provided that the following conditions are met: * * * Redistributions of source code must retain the above copyright notice, this * list of conditions and the following disclaimer. * * * Redistributions in binary form must reproduce the above copyright notice, * this list of conditions and the following disclaimer in the documentation * and/or other materials provided with the distribution. * * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE * POSSIBILITY OF SUCH DAMAGE. * * ***************************************************************************** * * Code common to the parsers. * */ #include #include #include #include #include #include #include #include void bc_parse_updateFunc(BcParse *p, size_t fidx) { p->fidx = fidx; p->func = bc_vec_item(&p->prog->fns, fidx); } inline void bc_parse_pushName(const BcParse *p, char *name, bool var) { bc_parse_pushIndex(p, bc_program_search(p->prog, name, var)); } /** * Updates the function, then pushes the instruction and the index. This is a * convenience function. * @param p The parser. * @param inst The instruction to push. * @param idx The index to push. */ static void bc_parse_update(BcParse *p, uchar inst, size_t idx) { bc_parse_updateFunc(p, p->fidx); bc_parse_push(p, inst); bc_parse_pushIndex(p, idx); } void bc_parse_addString(BcParse *p) { size_t idx; - BC_SIG_LOCK; - idx = bc_program_addString(p->prog, p->l.str.v, p->fidx); // Push the string info. bc_parse_update(p, BC_INST_STR, p->fidx); bc_parse_pushIndex(p, idx); - - BC_SIG_UNLOCK; } static void bc_parse_addNum(BcParse *p, const char *string) { BcVec *consts = &p->func->consts; size_t idx; BcConst *c; BcVec *slabs; + BC_SIG_ASSERT_LOCKED; + // Special case 0. if (bc_parse_zero[0] == string[0] && bc_parse_zero[1] == string[1]) { bc_parse_push(p, BC_INST_ZERO); return; } // Special case 1. if (bc_parse_one[0] == string[0] && bc_parse_one[1] == string[1]) { bc_parse_push(p, BC_INST_ONE); return; } // Get the index. idx = consts->len; - BC_SIG_LOCK; - // Get the right slab. slabs = p->fidx == BC_PROG_MAIN || p->fidx == BC_PROG_READ ? &vm.main_const_slab : &vm.other_slabs; // Push an empty constant. c = bc_vec_pushEmpty(consts); // Set the fields. c->val = bc_slabvec_strdup(slabs, string); c->base = BC_NUM_BIGDIG_MAX; // We need this to be able to tell that the number has not been allocated. bc_num_clear(&c->num); bc_parse_update(p, BC_INST_NUM, idx); - - BC_SIG_UNLOCK; } void bc_parse_number(BcParse *p) { #if BC_ENABLE_EXTRA_MATH char *exp = strchr(p->l.str.v, 'e'); size_t idx = SIZE_MAX; // Do we have a number in scientific notation? If so, add a nul byte where // the e is. if (exp != NULL) { idx = ((size_t) (exp - p->l.str.v)); *exp = 0; } #endif // BC_ENABLE_EXTRA_MATH bc_parse_addNum(p, p->l.str.v); #if BC_ENABLE_EXTRA_MATH // If we have a number in scientific notation... if (exp != NULL) { bool neg; // Figure out if the exponent is negative. neg = (*((char*) bc_vec_item(&p->l.str, idx + 1)) == BC_LEX_NEG_CHAR); // Add the number and instruction. bc_parse_addNum(p, bc_vec_item(&p->l.str, idx + 1 + neg)); bc_parse_push(p, BC_INST_LSHIFT + neg); } #endif // BC_ENABLE_EXTRA_MATH } void bc_parse_text(BcParse *p, const char *text, bool is_stdin) { + BC_SIG_LOCK; + // Make sure the pointer isn't invalidated. p->func = bc_vec_item(&p->prog->fns, p->fidx); bc_lex_text(&p->l, text, is_stdin); + + BC_SIG_UNLOCK; } void bc_parse_reset(BcParse *p) { BC_SIG_ASSERT_LOCKED; // Reset the function if it isn't main and switch to main. if (p->fidx != BC_PROG_MAIN) { bc_func_reset(p->func); bc_parse_updateFunc(p, BC_PROG_MAIN); } // Reset the lexer. p->l.i = p->l.len; p->l.t = BC_LEX_EOF; #if BC_ENABLED if (BC_IS_BC) { // Get rid of the bc parser state. p->auto_part = false; bc_vec_npop(&p->flags, p->flags.len - 1); bc_vec_popAll(&p->exits); bc_vec_popAll(&p->conds); bc_vec_popAll(&p->ops); } #endif // BC_ENABLED // Reset the program. This might clear the error. bc_program_reset(p->prog); // Jump if there is an error. if (BC_ERR(vm.status)) BC_JMP; } #ifndef NDEBUG void bc_parse_free(BcParse *p) { BC_SIG_ASSERT_LOCKED; assert(p != NULL); #if BC_ENABLED if (BC_IS_BC) { bc_vec_free(&p->flags); bc_vec_free(&p->exits); bc_vec_free(&p->conds); bc_vec_free(&p->ops); bc_vec_free(&p->buf); } #endif // BC_ENABLED bc_lex_free(&p->l); } #endif // NDEBUG void bc_parse_init(BcParse *p, BcProgram *prog, size_t func) { #if BC_ENABLED uint16_t flag = 0; #endif // BC_ENABLED BC_SIG_ASSERT_LOCKED; assert(p != NULL && prog != NULL); #if BC_ENABLED if (BC_IS_BC) { // We always want at least one flag set on the flags stack. bc_vec_init(&p->flags, sizeof(uint16_t), BC_DTOR_NONE); bc_vec_push(&p->flags, &flag); bc_vec_init(&p->exits, sizeof(BcInstPtr), BC_DTOR_NONE); bc_vec_init(&p->conds, sizeof(size_t), BC_DTOR_NONE); bc_vec_init(&p->ops, sizeof(BcLexType), BC_DTOR_NONE); bc_vec_init(&p->buf, sizeof(char), BC_DTOR_NONE); p->auto_part = false; } #endif // BC_ENABLED bc_lex_init(&p->l); // Set up the function. p->prog = prog; bc_parse_updateFunc(p, func); } diff --git a/contrib/bc/src/program.c b/contrib/bc/src/program.c index 1ff9c24f323b..bc5b88011638 100644 --- a/contrib/bc/src/program.c +++ b/contrib/bc/src/program.c @@ -1,3307 +1,3348 @@ /* * ***************************************************************************** * * SPDX-License-Identifier: BSD-2-Clause * * Copyright (c) 2018-2021 Gavin D. Howard and contributors. * * Redistribution and use in source and binary forms, with or without * modification, are permitted provided that the following conditions are met: * * * Redistributions of source code must retain the above copyright notice, this * list of conditions and the following disclaimer. * * * Redistributions in binary form must reproduce the above copyright notice, * this list of conditions and the following disclaimer in the documentation * and/or other materials provided with the distribution. * * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE * POSSIBILITY OF SUCH DAMAGE. * * ***************************************************************************** * * Code to execute bc programs. * */ #include #include #include #include #include #include #include #include #include #include /** * Quickly sets the const and strs vector pointers in the program. This is a * convenience function. * @param p The program. * @param f The new function. */ static inline void bc_program_setVecs(BcProgram *p, BcFunc *f) { + BC_SIG_ASSERT_LOCKED; p->consts = &f->consts; p->strs = &f->strs; } /** * Does a type check for something that expects a number. * @param r The result that will be checked. * @param n The result's number. */ static inline void bc_program_type_num(BcResult *r, BcNum *n) { #if BC_ENABLED // This should have already been taken care of. assert(r->t != BC_RESULT_VOID); #endif // BC_ENABLED if (BC_ERR(!BC_PROG_NUM(r, n))) bc_err(BC_ERR_EXEC_TYPE); } #if BC_ENABLED /** * Does a type check. * @param r The result to check. * @param t The type that the result should be. */ static void bc_program_type_match(BcResult *r, BcType t) { if (BC_ERR((r->t != BC_RESULT_ARRAY) != (!t))) bc_err(BC_ERR_EXEC_TYPE); } #endif // BC_ENABLED /** * Pulls an index out of a bytecode vector and updates the index into the vector * to point to the spot after the index. For more details on bytecode indices, * see the development manual (manuals/development.md#bytecode-indices). * @param code The bytecode vector. * @param bgn An in/out parameter; the index into the vector that will be * updated. * @return The index at @a bgn in the bytecode vector. */ static size_t bc_program_index(const char *restrict code, size_t *restrict bgn) { uchar amt = (uchar) code[(*bgn)++], i = 0; size_t res = 0; for (; i < amt; ++i, ++(*bgn)) { size_t temp = ((size_t) ((int) (uchar) code[*bgn]) & UCHAR_MAX); res |= (temp << (i * CHAR_BIT)); } return res; } /** * Returns a string from a result and its number. * @param p The program. * @param n The number tied to the result. * @return The string corresponding to the result and number. */ static char* bc_program_string(BcProgram *p, const BcNum *n) { BcFunc *f = bc_vec_item(&p->fns, n->rdx); return *((char**) bc_vec_item(&f->strs, n->scale)); } #if BC_ENABLED /** * Prepares the globals for a function call. This is only called when global * stacks are on because it pushes a copy of the current globals onto each of * their respective stacks. * @param p The program. */ static void bc_program_prepGlobals(BcProgram *p) { size_t i; for (i = 0; i < BC_PROG_GLOBALS_LEN; ++i) bc_vec_push(p->globals_v + i, p->globals + i); #if BC_ENABLE_EXTRA_MATH bc_rand_push(&p->rng); #endif // BC_ENABLE_EXTRA_MATH } /** * Pops globals stacks on returning from a function, or in the case of reset, * pops all but one item on each global stack. * @param p The program. * @param reset True if all but one item on each stack should be popped, false * otherwise. */ static void bc_program_popGlobals(BcProgram *p, bool reset) { size_t i; + BC_SIG_ASSERT_LOCKED; + for (i = 0; i < BC_PROG_GLOBALS_LEN; ++i) { BcVec *v = p->globals_v + i; bc_vec_npop(v, reset ? v->len - 1 : 1); p->globals[i] = BC_PROG_GLOBAL(v); } #if BC_ENABLE_EXTRA_MATH bc_rand_pop(&p->rng, reset); #endif // BC_ENABLE_EXTRA_MATH } /** * Derefeneces an array reference and returns a pointer to the real array. * @param p The program. * @param vec The reference vector. * @return A pointer to the desired array. */ static BcVec* bc_program_dereference(const BcProgram *p, BcVec *vec) { BcVec *v; size_t vidx, nidx, i = 0; // We want to be sure we have a reference vector. assert(vec->size == sizeof(uchar)); // Get the index of the vector in arrs, then the index of the original // referenced vector. vidx = bc_program_index(vec->v, &i); nidx = bc_program_index(vec->v, &i); v = bc_vec_item(bc_vec_item(&p->arrs, vidx), nidx); // We want to be sure we do *not* have a reference vector. assert(v->size != sizeof(uchar)); return v; } #endif // BC_ENABLED /** * Creates a BcNum from a BcBigDig and pushes onto the results stack. This is a * convenience function. * @param p The program. * @param dig The BcBigDig to push onto the results stack. * @param type The type that the pushed result should be. */ static void bc_program_pushBigdig(BcProgram *p, BcBigDig dig, BcResultType type) { BcResult res; res.t = type; BC_SIG_LOCK; bc_num_createFromBigdig(&res.d.n, dig); bc_vec_push(&p->results, &res); BC_SIG_UNLOCK; } size_t bc_program_addString(BcProgram *p, const char *str, size_t fidx) { BcFunc *f; char **str_ptr; BcVec *slabs; BC_SIG_ASSERT_LOCKED; // Push an empty string on the proper vector. f = bc_vec_item(&p->fns, fidx); str_ptr = bc_vec_pushEmpty(&f->strs); // Figure out which slab vector to use. slabs = fidx == BC_PROG_MAIN || fidx == BC_PROG_READ ? &vm.main_slabs : &vm.other_slabs; *str_ptr = bc_slabvec_strdup(slabs, str); return f->strs.len - 1; } size_t bc_program_search(BcProgram *p, const char *id, bool var) { BcVec *v, *map; size_t i; + BC_SIG_ASSERT_LOCKED; + // Grab the right vector and map. v = var ? &p->vars : &p->arrs; map = var ? &p->var_map : &p->arr_map; - BC_SIG_LOCK; - // We do an insert because the variable might not exist yet. This is because // the parser calls this function. If the insert succeeds, we create a stack // for the variable/array. But regardless, bc_map_insert() gives us the // index of the item in i. if (bc_map_insert(map, id, v->len, &i)) { BcVec *temp = bc_vec_pushEmpty(v); bc_array_init(temp, var); } - BC_SIG_UNLOCK; - return ((BcId*) bc_vec_item(map, i))->idx; } /** * Returns the correct variable or array stack for the type. * @param p The program. * @param idx The index of the variable or array in the variable or array * vector. * @param type The type of vector to return. * @return A pointer to the variable or array stack. */ static inline BcVec* bc_program_vec(const BcProgram *p, size_t idx, BcType type) { const BcVec *v = (type == BC_TYPE_VAR) ? &p->vars : &p->arrs; return bc_vec_item(v, idx); } /** * Returns a pointer to the BcNum corresponding to the result. There is one * case, however, where this returns a pointer to a BcVec: if the type of the * result is array. In that case, the pointer is casted to a pointer to BcNum, * but is never used. The function that calls this expecting an array casts the * pointer back. This function is called a lot and needs to be as fast as * possible. * @param p The program. * @param r The result whose number will be returned. * @return The BcNum corresponding to the result. */ static BcNum* bc_program_num(BcProgram *p, BcResult *r) { BcNum *n; #ifdef _WIN32 // Windows made it an error to not initialize this, so shut it up. // I don't want to do this on other platforms because this procedure // is one of the most heavily-used, and eliminating the initialization // is a performance win. n = NULL; #endif // _WIN32 switch (r->t) { case BC_RESULT_STR: case BC_RESULT_TEMP: case BC_RESULT_IBASE: case BC_RESULT_SCALE: case BC_RESULT_OBASE: #if BC_ENABLE_EXTRA_MATH case BC_RESULT_SEED: #endif // BC_ENABLE_EXTRA_MATH { n = &r->d.n; break; } case BC_RESULT_VAR: case BC_RESULT_ARRAY: case BC_RESULT_ARRAY_ELEM: { BcVec *v; BcType type = (r->t == BC_RESULT_VAR) ? BC_TYPE_VAR : BC_TYPE_ARRAY; // Get the correct variable or array vector. v = bc_program_vec(p, r->d.loc.loc, type); // Surprisingly enough, the hard case is *not* returning an array; // it's returning an array element. This is because we have to dig // deeper to get *to* the element. That's what the code inside this // if statement does. if (r->t == BC_RESULT_ARRAY_ELEM) { size_t idx = r->d.loc.idx; v = bc_vec_top(v); #if BC_ENABLED // If this is true, we have a reference vector, so dereference // it. The reason we don't need to worry about it for returning // a straight array is because we only care about references // when we access elements of an array that is a reference. That // is this code, so in essence, this line takes care of arrays // as well. if (v->size == sizeof(uchar)) v = bc_program_dereference(p, v); #endif // BC_ENABLED // We want to be sure we got a valid array of numbers. assert(v->size == sizeof(BcNum)); // The bc spec says that if an element is accessed that does not // exist, it should be preinitialized to 0. Well, if we access // an element *way* out there, we have to preinitialize all // elements between the current last element and the actual // accessed element. if (v->len <= idx) { BC_SIG_LOCK; bc_array_expand(v, bc_vm_growSize(idx, 1)); BC_SIG_UNLOCK; } n = bc_vec_item(v, idx); } // This is either a number (for a var) or an array (for an array). // Because bc_vec_top() returns a void*, we don't need to cast. else n = bc_vec_top(v); break; } case BC_RESULT_ZERO: { n = &vm.zero; break; } case BC_RESULT_ONE: { n = &vm.one; break; } #if BC_ENABLED // We should never get here; this is taken care of earlier because a // result is expected. case BC_RESULT_VOID: #ifndef NDEBUG { abort(); } #endif // NDEBUG // Fallthrough case BC_RESULT_LAST: { n = &p->last; break; } #endif // BC_ENABLED } return n; } /** * Prepares an operand for use. * @param p The program. * @param r An out parameter; this is set to the pointer to the result that * we care about. * @param n An out parameter; this is set to the pointer to the number that * we care about. * @param idx The index of the result from the top of the results stack. */ static void bc_program_operand(BcProgram *p, BcResult **r, BcNum **n, size_t idx) { *r = bc_vec_item_rev(&p->results, idx); #if BC_ENABLED if (BC_ERR((*r)->t == BC_RESULT_VOID)) bc_err(BC_ERR_EXEC_VOID_VAL); #endif // BC_ENABLED *n = bc_program_num(p, *r); } /** * Prepares the operands of a binary operator. * @param p The program. * @param l An out parameter; this is set to the pointer to the result for * the left operand. * @param ln An out parameter; this is set to the pointer to the number for * the left operand. * @param r An out parameter; this is set to the pointer to the result for * the right operand. * @param rn An out parameter; this is set to the pointer to the number for * the right operand. * @param idx The starting index where the operands are in the results stack, * starting from the top. */ static void bc_program_binPrep(BcProgram *p, BcResult **l, BcNum **ln, BcResult **r, BcNum **rn, size_t idx) { BcResultType lt; assert(p != NULL && l != NULL && ln != NULL && r != NULL && rn != NULL); #ifndef BC_PROG_NO_STACK_CHECK // Check the stack for dc. if (BC_IS_DC) { if (BC_ERR(!BC_PROG_STACK(&p->results, idx + 2))) bc_err(BC_ERR_EXEC_STACK); } #endif // BC_PROG_NO_STACK_CHECK assert(BC_PROG_STACK(&p->results, idx + 2)); // Get the operands. bc_program_operand(p, l, ln, idx + 1); bc_program_operand(p, r, rn, idx); lt = (*l)->t; #if BC_ENABLED // bc_program_operand() checked these for us. assert(lt != BC_RESULT_VOID && (*r)->t != BC_RESULT_VOID); #endif // BC_ENABLED // We run this again under these conditions in case any vector has been // reallocated out from under the BcNums or arrays we had. In other words, // this is to fix pointer invalidation. if (lt == (*r)->t && (lt == BC_RESULT_VAR || lt == BC_RESULT_ARRAY_ELEM)) *ln = bc_program_num(p, *l); if (BC_ERR(lt == BC_RESULT_STR)) bc_err(BC_ERR_EXEC_TYPE); } /** * Prepares the operands of a binary operator and type checks them. This is * separate from bc_program_binPrep() because some places want this, others want * bc_program_binPrep(). * @param p The program. * @param l An out parameter; this is set to the pointer to the result for * the left operand. * @param ln An out parameter; this is set to the pointer to the number for * the left operand. * @param r An out parameter; this is set to the pointer to the result for * the right operand. * @param rn An out parameter; this is set to the pointer to the number for * the right operand. * @param idx The starting index where the operands are in the results stack, * starting from the top. */ static void bc_program_binOpPrep(BcProgram *p, BcResult **l, BcNum **ln, BcResult **r, BcNum **rn, size_t idx) { bc_program_binPrep(p, l, ln, r, rn, idx); bc_program_type_num(*l, *ln); bc_program_type_num(*r, *rn); } /** * Prepares the operands of an assignment operator. * @param p The program. * @param l An out parameter; this is set to the pointer to the result for the * left operand. * @param ln An out parameter; this is set to the pointer to the number for the * left operand. * @param r An out parameter; this is set to the pointer to the result for the * right operand. * @param rn An out parameter; this is set to the pointer to the number for the * right operand. */ static void bc_program_assignPrep(BcProgram *p, BcResult **l, BcNum **ln, BcResult **r, BcNum **rn) { BcResultType lt, min; // This is the min non-allowable result type. dc allows strings. min = BC_RESULT_TEMP - ((unsigned int) (BC_IS_BC)); // Prepare the operands. bc_program_binPrep(p, l, ln, r, rn, 0); lt = (*l)->t; // Typecheck the left. if (BC_ERR(lt >= min && lt <= BC_RESULT_ONE)) bc_err(BC_ERR_EXEC_TYPE); // Strings can be assigned to variables. We are already good if we are // assigning a string. bool good = ((*r)->t == BC_RESULT_STR && lt <= BC_RESULT_ARRAY_ELEM); assert(BC_PROG_STR(*rn) || (*r)->t != BC_RESULT_STR); // If not, type check for a number. if (!good) bc_program_type_num(*r, *rn); } /** * Prepares a single operand and type checks it. This is separate from * bc_program_operand() because different places want one or the other. * @param p The program. * @param r An out parameter; this is set to the pointer to the result that * we care about. * @param n An out parameter; this is set to the pointer to the number that * we care about. * @param idx The index of the result from the top of the results stack. */ static void bc_program_prep(BcProgram *p, BcResult **r, BcNum **n, size_t idx) { assert(p != NULL && r != NULL && n != NULL); #ifndef BC_PROG_NO_STACK_CHECK // Check the stack for dc. if (BC_IS_DC) { if (BC_ERR(!BC_PROG_STACK(&p->results, idx + 1))) bc_err(BC_ERR_EXEC_STACK); } #endif // BC_PROG_NO_STACK_CHECK assert(BC_PROG_STACK(&p->results, idx + 1)); bc_program_operand(p, r, n, idx); // dc does not allow strings in this case. bc_program_type_num(*r, *n); } /** * Prepares and returns a clean result for the result of an operation. * @param p The program. * @return A clean result. */ static BcResult* bc_program_prepResult(BcProgram *p) { BcResult *res = bc_vec_pushEmpty(&p->results); bc_result_clear(res); return res; } /** * Prepares a constant for use. This parses the constant into a number and then * pushes that number onto the results stack. * @param p The program. * @param code The bytecode vector that we will pull the index of the constant * from. * @param bgn An in/out parameter; marks the start of the index in the * bytecode vector and will be updated to point to after the index. */ static void bc_program_const(BcProgram *p, const char *code, size_t *bgn) { // I lied. I actually push the result first. I can do this because the // result will be popped on error. I also get the constant itself. BcResult *r = bc_program_prepResult(p); BcConst *c = bc_vec_item(p->consts, bc_program_index(code, bgn)); BcBigDig base = BC_PROG_IBASE(p); // Only reparse if the base changed. if (c->base != base) { // Allocate if we haven't yet. if (c->num.num == NULL) { BC_SIG_LOCK; bc_num_init(&c->num, BC_NUM_RDX(strlen(c->val))); BC_SIG_UNLOCK; } // bc_num_parse() should only do operations that cannot fail. bc_num_parse(&c->num, c->val, base); c->base = base; } BC_SIG_LOCK; bc_num_createCopy(&r->d.n, &c->num); BC_SIG_UNLOCK; } /** * Executes a binary operator operation. * @param p The program. * @param inst The instruction corresponding to the binary operator to execute. */ static void bc_program_op(BcProgram *p, uchar inst) { BcResult *opd1, *opd2, *res; BcNum *n1, *n2; size_t idx = inst - BC_INST_POWER; res = bc_program_prepResult(p); bc_program_binOpPrep(p, &opd1, &n1, &opd2, &n2, 1); BC_SIG_LOCK; // Initialize the number with enough space, using the correct // BcNumBinaryOpReq function. This looks weird because it is executing an // item of an array. Rest assured that item is a function. bc_num_init(&res->d.n, bc_program_opReqs[idx](n1, n2, BC_PROG_SCALE(p))); BC_SIG_UNLOCK; assert(BC_NUM_RDX_VALID(n1)); assert(BC_NUM_RDX_VALID(n2)); // Run the operation. This also executes an item of an array. bc_program_ops[idx](n1, n2, &res->d.n, BC_PROG_SCALE(p)); bc_program_retire(p, 1, 2); } /** * Executes a read() or ? command. * @param p The program. */ static void bc_program_read(BcProgram *p) { BcStatus s; BcInstPtr ip; size_t i; const char* file; bool is_stdin; BcFunc *f = bc_vec_item(&p->fns, BC_PROG_READ); // If we are already executing a read, that is an error. So look for a read // and barf. for (i = 0; i < p->stack.len; ++i) { BcInstPtr *ip_ptr = bc_vec_item(&p->stack, i); if (ip_ptr->func == BC_PROG_READ) bc_err(BC_ERR_EXEC_REC_READ); } BC_SIG_LOCK; // Save the filename because we are going to overwrite it. file = vm.file; is_stdin = vm.is_stdin; // It is a parse error if there needs to be more than one line, so we unset // this to tell the lexer to not request more. We set it back later. vm.is_stdin = false; if (!BC_PARSE_IS_INITED(&vm.read_prs, p)) { // We need to parse, but we don't want to use the existing parser // because it has state it needs to keep. (It could have a partial parse // state.) So we create a new parser. This parser is in the BcVm struct // so that it is not local, which means that a longjmp() could change // it. bc_parse_init(&vm.read_prs, p, BC_PROG_READ); // We need a separate input buffer; that's why it is also in the BcVm // struct. bc_vec_init(&vm.read_buf, sizeof(char), BC_DTOR_NONE); } // This needs to be updated because the parser could have been used // somewhere else else bc_parse_updateFunc(&vm.read_prs, BC_PROG_READ); BC_SETJMP_LOCKED(exec_err); BC_SIG_UNLOCK; // Set up the lexer and the read function. bc_lex_file(&vm.read_prs.l, bc_program_stdin_name); bc_vec_popAll(&f->code); // Read a line. if (!BC_R) s = bc_read_line(&vm.read_buf, ""); else s = bc_read_line(&vm.read_buf, BC_IS_BC ? "read> " : "?> "); // We should *not* have run into EOF. if (s == BC_STATUS_EOF) bc_err(BC_ERR_EXEC_READ_EXPR); // Parse *one* expression. bc_parse_text(&vm.read_prs, vm.read_buf.v, false); + BC_SIG_LOCK; vm.expr(&vm.read_prs, BC_PARSE_NOREAD | BC_PARSE_NEEDVAL); + BC_SIG_UNLOCK; // We *must* have a valid expression. A semicolon cannot end an expression, // although EOF can. if (BC_ERR(vm.read_prs.l.t != BC_LEX_NLINE && vm.read_prs.l.t != BC_LEX_EOF)) { bc_err(BC_ERR_EXEC_READ_EXPR); } #if BC_ENABLED // Push on the globals stack if necessary. if (BC_G) bc_program_prepGlobals(p); #endif // BC_ENABLED // Set up a new BcInstPtr. ip.func = BC_PROG_READ; ip.idx = 0; ip.len = p->results.len; // Update this pointer, just in case. f = bc_vec_item(&p->fns, BC_PROG_READ); // We want a return instruction to simplify things. bc_vec_pushByte(&f->code, vm.read_ret); + + // This lock is here to make sure dc's tail calls are the same length. + BC_SIG_LOCK; bc_vec_push(&p->stack, &ip); #if DC_ENABLED // We need a new tail call entry for dc. if (BC_IS_DC) { size_t temp = 0; bc_vec_push(&p->tail_calls, &temp); } #endif // DC_ENABLED exec_err: BC_SIG_MAYLOCK; vm.is_stdin = is_stdin; vm.file = file; BC_LONGJMP_CONT; } #if BC_ENABLE_EXTRA_MATH /** * Execute a rand(). * @param p The program. */ static void bc_program_rand(BcProgram *p) { BcRand rand = bc_rand_int(&p->rng); bc_program_pushBigdig(p, (BcBigDig) rand, BC_RESULT_TEMP); #ifndef NDEBUG // This is just to ensure that the generated number is correct. I also use // braces because I declare every local at the top of the scope. { BcResult *r = bc_vec_top(&p->results); assert(BC_NUM_RDX_VALID_NP(r->d.n)); } #endif // NDEBUG } #endif // BC_ENABLE_EXTRA_MATH /** * Prints a series of characters, without escapes. * @param str The string (series of characters). */ static void bc_program_printChars(const char *str) { const char *nl; size_t len = vm.nchars + strlen(str); + sig_atomic_t lock; + + BC_SIG_TRYLOCK(lock); bc_file_puts(&vm.fout, bc_flush_save, str); // We need to update the number of characters, so we find the last newline // and set the characters accordingly. nl = strrchr(str, '\n'); if (nl != NULL) len = strlen(nl + 1); vm.nchars = len > UINT16_MAX ? UINT16_MAX : (uint16_t) len; + + BC_SIG_TRYUNLOCK(lock); } /** * Prints a string with escapes. * @param str The string. */ static void bc_program_printString(const char *restrict str) { size_t i, len = strlen(str); #if DC_ENABLED // This is to ensure a nul byte is printed for dc's stream operation. if (!len && BC_IS_DC) { bc_vm_putchar('\0', bc_flush_save); return; } #endif // DC_ENABLED // Loop over the characters, processing escapes and printing the rest. for (i = 0; i < len; ++i) { int c = str[i]; // If we have an escape... if (c == '\\' && i != len - 1) { const char *ptr; // Get the escape character and its companion. c = str[++i]; ptr = strchr(bc_program_esc_chars, c); // If we have a companion character... if (ptr != NULL) { // We need to specially handle a newline. - if (c == 'n') vm.nchars = UINT16_MAX; + if (c == 'n') { + BC_SIG_LOCK; + vm.nchars = UINT16_MAX; + BC_SIG_UNLOCK; + } // Grab the actual character. c = bc_program_esc_seqs[(size_t) (ptr - bc_program_esc_chars)]; } else { // Just print the backslash if there is no companion character. // The following character will be printed later after the outer // if statement. bc_vm_putchar('\\', bc_flush_save); } } bc_vm_putchar(c, bc_flush_save); } } /** * Executes a print. This function handles all printing except streaming. * @param p The program. * @param inst The instruction for the type of print we are doing. * @param idx The index of the result that we are printing. */ static void bc_program_print(BcProgram *p, uchar inst, size_t idx) { BcResult *r; char *str; BcNum *n; bool pop = (inst != BC_INST_PRINT); assert(p != NULL); #ifndef BC_PROG_NO_STACK_CHECK if (BC_IS_DC) { if (BC_ERR(!BC_PROG_STACK(&p->results, idx + 1))) bc_err(BC_ERR_EXEC_STACK); } #endif // BC_PROG_NO_STACK_CHECK assert(BC_PROG_STACK(&p->results, idx + 1)); r = bc_vec_item_rev(&p->results, idx); #if BC_ENABLED // If we have a void value, that's not necessarily an error. It is if pop is // true because that means that we are executing a print statement, but // attempting to do a print on a lone void value is allowed because that's // exactly how we want void values used. if (r->t == BC_RESULT_VOID) { if (BC_ERR(pop)) bc_err(BC_ERR_EXEC_VOID_VAL); bc_vec_pop(&p->results); return; } #endif // BC_ENABLED n = bc_program_num(p, r); // If we have a number... if (BC_PROG_NUM(r, n)) { #if BC_ENABLED assert(inst != BC_INST_PRINT_STR); #endif // BC_ENABLED // Print the number. bc_num_print(n, BC_PROG_OBASE(p), !pop); #if BC_ENABLED // Need to store the number in last. if (BC_IS_BC) bc_num_copy(&p->last, n); #endif // BC_ENABLED } else { // We want to flush any stuff in the stdout buffer first. bc_file_flush(&vm.fout, bc_flush_save); str = bc_program_string(p, n); #if BC_ENABLED if (inst == BC_INST_PRINT_STR) bc_program_printChars(str); else #endif // BC_ENABLED { bc_program_printString(str); // Need to print a newline only in this case. if (inst == BC_INST_PRINT) bc_vm_putchar('\n', bc_flush_err); } } // bc always pops. if (BC_IS_BC || pop) bc_vec_pop(&p->results); } void bc_program_negate(BcResult *r, BcNum *n) { bc_num_copy(&r->d.n, n); if (BC_NUM_NONZERO(&r->d.n)) BC_NUM_NEG_TGL_NP(r->d.n); } void bc_program_not(BcResult *r, BcNum *n) { if (!bc_num_cmpZero(n)) bc_num_one(&r->d.n); } #if BC_ENABLE_EXTRA_MATH void bc_program_trunc(BcResult *r, BcNum *n) { bc_num_copy(&r->d.n, n); bc_num_truncate(&r->d.n, n->scale); } #endif // BC_ENABLE_EXTRA_MATH /** * Runs a unary operation. * @param p The program. * @param inst The unary operation. */ static void bc_program_unary(BcProgram *p, uchar inst) { BcResult *res, *ptr; BcNum *num; res = bc_program_prepResult(p); bc_program_prep(p, &ptr, &num, 1); BC_SIG_LOCK; bc_num_init(&res->d.n, num->len); BC_SIG_UNLOCK; // This calls a function that is in an array. bc_program_unarys[inst - BC_INST_NEG](res, num); bc_program_retire(p, 1, 1); } /** * Executes a logical operator. * @param p The program. * @param inst The operator. */ static void bc_program_logical(BcProgram *p, uchar inst) { BcResult *opd1, *opd2, *res; BcNum *n1, *n2; bool cond = 0; ssize_t cmp; res = bc_program_prepResult(p); // All logical operators (except boolean not, which is taken care of by // bc_program_unary()), are binary operators. bc_program_binOpPrep(p, &opd1, &n1, &opd2, &n2, 1); // Boolean and and or are not short circuiting. This is why; they can be // implemented much easier this way. if (inst == BC_INST_BOOL_AND) cond = (bc_num_cmpZero(n1) && bc_num_cmpZero(n2)); else if (inst == BC_INST_BOOL_OR) cond = (bc_num_cmpZero(n1) || bc_num_cmpZero(n2)); else { // We have a relational operator, so do a comparison. cmp = bc_num_cmp(n1, n2); switch (inst) { case BC_INST_REL_EQ: { cond = (cmp == 0); break; } case BC_INST_REL_LE: { cond = (cmp <= 0); break; } case BC_INST_REL_GE: { cond = (cmp >= 0); break; } case BC_INST_REL_NE: { cond = (cmp != 0); break; } case BC_INST_REL_LT: { cond = (cmp < 0); break; } case BC_INST_REL_GT: { cond = (cmp > 0); break; } #ifndef NDEBUG default: { // There is a bug if we get here. abort(); } #endif // NDEBUG } } BC_SIG_LOCK; bc_num_init(&res->d.n, BC_NUM_DEF_SIZE); BC_SIG_UNLOCK; if (cond) bc_num_one(&res->d.n); bc_program_retire(p, 1, 2); } /** * Assigns a string to a variable. * @param p The program. * @param num The location of the string as a BcNum. * @param v The stack for the variable. * @param push Whether to push the string or not. To push means to move the * string from the results stack and push it onto the variable * stack. */ static void bc_program_assignStr(BcProgram *p, BcNum *num, BcVec *v, bool push) { BcNum *n; assert(BC_PROG_STACK(&p->results, 1 + !push)); assert(num != NULL && num->num == NULL && num->cap == 0); // If we are not pushing onto the variable stack, we need to replace the // top of the variable stack. if (!push) bc_vec_pop(v); bc_vec_npop(&p->results, 1 + !push); n = bc_vec_pushEmpty(v); // We can just copy because the num should not have allocated anything. memcpy(n, num, sizeof(BcNum)); } /** * Copies a value to a variable. This is used for storing in dc as well as to * set function parameters to arguments in bc. * @param p The program. * @param idx The index of the variable or array to copy to. * @param t The type to copy to. This could be a variable or an array. * @param last Whether to grab the last item on the variable stack or not (for * bc function parameters). This is important because if a new * value has been pushed to the variable already, we need to grab * the value pushed before. This happens when you have a parameter * named something like "x", and a variable "x" is passed to * another parameter. */ static void bc_program_copyToVar(BcProgram *p, size_t idx, BcType t, bool last) { BcResult *ptr = NULL, r; BcVec *vec; BcNum *n = NULL; bool var = (t == BC_TYPE_VAR); #if DC_ENABLED // Check the stack for dc. if (BC_IS_DC) { if (BC_ERR(!BC_PROG_STACK(&p->results, 1))) bc_err(BC_ERR_EXEC_STACK); } #endif assert(BC_PROG_STACK(&p->results, 1)); bc_program_operand(p, &ptr, &n, 0); #if BC_ENABLED // Get the variable for a bc function call. if (BC_IS_BC) { // Type match the result. bc_program_type_match(ptr, t); // Get the variable or array, taking care to get the real item. We take // care of last with arrays later. if (!last && var) n = bc_vec_item_rev(bc_program_vec(p, ptr->d.loc.loc, t), 1); } #endif // BC_ENABLED vec = bc_program_vec(p, idx, t); // We can shortcut in dc if it's assigning a string by using // bc_program_assignStr(). if (ptr->t == BC_RESULT_STR) { assert(BC_PROG_STR(n)); if (BC_ERR(!var)) bc_err(BC_ERR_EXEC_TYPE); bc_program_assignStr(p, n, vec, true); return; } BC_SIG_LOCK; // Just create and copy for a normal variable. if (var) { if (BC_PROG_STR(n)) memcpy(&r.d.n, n, sizeof(BcNum)); else bc_num_createCopy(&r.d.n, n); } else { // If we get here, we are handling an array. This is one place we need // to cast the number from bc_program_num() to a vector. BcVec *v = (BcVec*) n, *rv = &r.d.v; #if BC_ENABLED if (BC_IS_BC) { BcVec *parent; bool ref, ref_size; // We need to figure out if the parameter is a reference or not and // construct the reference vector, if necessary. So this gets the // parent stack for the array. parent = bc_program_vec(p, ptr->d.loc.loc, t); assert(parent != NULL); // This takes care of last for arrays. Mostly. if (!last) v = bc_vec_item_rev(parent, !last); assert(v != NULL); // True if we are using a reference. ref = (v->size == sizeof(BcNum) && t == BC_TYPE_REF); // True if we already have a reference vector. This is slightly // (okay, a lot; it just doesn't look that way) different from // above. The above means that we need to construct a reference // vector, whereas this means that we have one and we might have to // *dereference* it. ref_size = (v->size == sizeof(uchar)); // If we *should* have a reference. if (ref || (ref_size && t == BC_TYPE_REF)) { // Create a new reference vector. bc_vec_init(rv, sizeof(uchar), BC_DTOR_NONE); // If this is true, then we need to construct a reference. if (ref) { assert(parent->len >= (size_t) (!last + 1)); // Make sure the pointer was not invalidated. vec = bc_program_vec(p, idx, t); // Push the indices onto the reference vector. This takes // care of last; it ensures the reference goes to the right // place. bc_vec_pushIndex(rv, ptr->d.loc.loc); bc_vec_pushIndex(rv, parent->len - !last - 1); } // If we get here, we are copying a ref to a ref. Just push a // copy of all of the bytes. else bc_vec_npush(rv, v->len * sizeof(uchar), v->v); // Push the reference vector onto the array stack and pop the // source. bc_vec_push(vec, &r.d); bc_vec_pop(&p->results); // We need to return early to avoid executing code that we must // not touch. BC_SIG_UNLOCK; return; } // If we get here, we have a reference, but we need an array, so // dereference the array. else if (ref_size && t != BC_TYPE_REF) v = bc_program_dereference(p, v); } #endif // BC_ENABLED // If we get here, we need to copy the array because in bc, all // arguments are passed by value. Yes, this is expensive. bc_array_init(rv, true); bc_array_copy(rv, v); } // Push the vector onto the array stack and pop the source. bc_vec_push(vec, &r.d); bc_vec_pop(&p->results); BC_SIG_UNLOCK; } /** * Executes an assignment operator. * @param p The program. * @param inst The assignment operator to execute. */ static void bc_program_assign(BcProgram *p, uchar inst) { // The local use_val is true when the assigned value needs to be copied. BcResult *left, *right, res; BcNum *l, *r; bool ob, sc, use_val = BC_INST_USE_VAL(inst); bc_program_assignPrep(p, &left, &l, &right, &r); // Assigning to a string should be impossible simply because of the parse. assert(left->t != BC_RESULT_STR); // If we are assigning a string... if (right->t == BC_RESULT_STR) { assert(BC_PROG_STR(r)); #if BC_ENABLED if (inst != BC_INST_ASSIGN && inst != BC_INST_ASSIGN_NO_VAL) bc_err(BC_ERR_EXEC_TYPE); #endif // BC_ENABLED // If we are assigning to an array element... if (left->t == BC_RESULT_ARRAY_ELEM) { BC_SIG_LOCK; // We need to free the number and clear it. bc_num_free(l); memcpy(l, r, sizeof(BcNum)); // Now we can pop the results. bc_vec_npop(&p->results, 2); BC_SIG_UNLOCK; } else { // If we get here, we are assigning to a variable, which we can use // bc_program_assignStr() for. BcVec *v = bc_program_vec(p, left->d.loc.loc, BC_TYPE_VAR); bc_program_assignStr(p, r, v, false); } #if BC_ENABLED // If this is true, the value is going to be used again, so we want to // push a temporary with the string. if (inst == BC_INST_ASSIGN) { res.t = BC_RESULT_STR; memcpy(&res.d.n, r, sizeof(BcNum)); bc_vec_push(&p->results, &res); } #endif // BC_ENABLED // By using bc_program_assignStr(), we short-circuited this, so return. return; } // If we have a normal assignment operator, not a math one... if (BC_INST_IS_ASSIGN(inst)) { // Assigning to a variable that has a string here is fine because there // is no math done on it. // BC_RESULT_TEMP, BC_RESULT_IBASE, BC_RESULT_OBASE, BC_RESULT_SCALE, // and BC_RESULT_SEED all have temporary copies. Because that's the // case, we can free the left and just move the value over. We set the // type of right to BC_RESULT_ZERO in order to prevent it from being // freed. We also don't have to worry about BC_RESULT_STR because it's // take care of above. if (right->t == BC_RESULT_TEMP || right->t >= BC_RESULT_IBASE) { BC_SIG_LOCK; bc_num_free(l); memcpy(l, r, sizeof(BcNum)); right->t = BC_RESULT_ZERO; BC_SIG_UNLOCK; } // Copy over. else bc_num_copy(l, r); } #if BC_ENABLED else { // If we get here, we are doing a math assignment (+=, -=, etc.). So // we need to prepare for a binary operator. BcBigDig scale = BC_PROG_SCALE(p); // At this point, the left side could still be a string because it could // be a variable that has the string. If that's the case, we have a type // error. if (BC_PROG_STR(l)) bc_err(BC_ERR_EXEC_TYPE); // Get the right type of assignment operator, whether val is used or // NO_VAL for performance. if (!use_val) inst -= (BC_INST_ASSIGN_POWER_NO_VAL - BC_INST_ASSIGN_POWER); assert(BC_NUM_RDX_VALID(l)); assert(BC_NUM_RDX_VALID(r)); // Run the actual operation. We do not need worry about reallocating l // because bc_num_binary() does that behind the scenes for us. bc_program_ops[inst - BC_INST_ASSIGN_POWER](l, r, l, scale); } #endif // BC_ENABLED ob = (left->t == BC_RESULT_OBASE); sc = (left->t == BC_RESULT_SCALE); // The globals need special handling, especially the non-seed ones. The // first part of the if statement handles them. if (ob || sc || left->t == BC_RESULT_IBASE) { BcVec *v; BcBigDig *ptr, *ptr_t, val, max, min; // Get the actual value. val = bc_num_bigdig(l); // Scale needs handling separate from ibase and obase. if (sc) { // Set the min and max. min = 0; max = vm.maxes[BC_PROG_GLOBALS_SCALE]; // Get a pointer to the stack and to the current value. v = p->globals_v + BC_PROG_GLOBALS_SCALE; ptr_t = p->globals + BC_PROG_GLOBALS_SCALE; } else { // Set the min and max. min = BC_NUM_MIN_BASE; if (BC_ENABLE_EXTRA_MATH && ob && (BC_IS_DC || !BC_IS_POSIX)) min = 0; max = vm.maxes[ob + BC_PROG_GLOBALS_IBASE]; // Get a pointer to the stack and to the current value. v = p->globals_v + BC_PROG_GLOBALS_IBASE + ob; ptr_t = p->globals + BC_PROG_GLOBALS_IBASE + ob; } // Check for error. if (BC_ERR(val > max || val < min)) { // This grabs the right error. BcErr e = left->t - BC_RESULT_IBASE + BC_ERR_EXEC_IBASE; bc_verr(e, min, max); } // Set the top of the stack and the actual global value. ptr = bc_vec_top(v); *ptr = val; *ptr_t = val; } #if BC_ENABLE_EXTRA_MATH // To assign to steed, let bc_num_rng() do its magic. else if (left->t == BC_RESULT_SEED) bc_num_rng(l, &p->rng); #endif // BC_ENABLE_EXTRA_MATH BC_SIG_LOCK; // If we needed to use the value, then we need to copy it. Otherwise, we can // pop indiscriminately. Oh, and the copy should be a BC_RESULT_TEMP. if (use_val) { bc_num_createCopy(&res.d.n, l); res.t = BC_RESULT_TEMP; bc_vec_npop(&p->results, 2); bc_vec_push(&p->results, &res); } else bc_vec_npop(&p->results, 2); BC_SIG_UNLOCK; } /** * Pushes a variable's value onto the results stack. * @param p The program. * @param code The bytecode vector to pull the variable's index out of. * @param bgn An in/out parameter; the start of the index in the bytecode * vector, and will be updated to point after the index on return. * @param pop True if the variable's value should be popped off its stack. * This is only used in dc. * @param copy True if the variable's value should be copied to the results * stack. This is only used in dc. */ static void bc_program_pushVar(BcProgram *p, const char *restrict code, size_t *restrict bgn, bool pop, bool copy) { BcResult r; size_t idx = bc_program_index(code, bgn); // Set the result appropriately. r.t = BC_RESULT_VAR; r.d.loc.loc = idx; #if DC_ENABLED // If this condition is true, then we have the hard case, where we have to // adjust dc registers. if (BC_IS_DC && (pop || copy)) { // Get the stack for the variable and the number at the top. BcVec *v = bc_program_vec(p, idx, BC_TYPE_VAR); BcNum *num = bc_vec_top(v); // Ensure there are enough elements on the stack. if (BC_ERR(!BC_PROG_STACK(v, 2 - copy))) { const char *name = bc_map_name(&p->var_map, idx); bc_verr(BC_ERR_EXEC_STACK_REGISTER, name); } assert(BC_PROG_STACK(v, 2 - copy)); // If the top of the stack is actually a number... if (!BC_PROG_STR(num)) { BC_SIG_LOCK; // Create a copy to go onto the results stack as appropriate. r.t = BC_RESULT_TEMP; bc_num_createCopy(&r.d.n, num); // If we are not actually copying, we need to do a replace, so pop. if (!copy) bc_vec_pop(v); bc_vec_push(&p->results, &r); BC_SIG_UNLOCK; return; } else { // Set the string result. We can just memcpy because all of the // fields in the num should be cleared. memcpy(&r.d.n, num, sizeof(BcNum)); r.t = BC_RESULT_STR; } // If we are not actually copying, we need to do a replace, so pop. if (!copy) bc_vec_pop(v); } #endif // DC_ENABLED bc_vec_push(&p->results, &r); } /** * Pushes an array or an array element onto the results stack. * @param p The program. * @param code The bytecode vector to pull the variable's index out of. * @param bgn An in/out parameter; the start of the index in the bytecode * vector, and will be updated to point after the index on return. * @param inst The instruction; whether to push an array or an array element. */ static void bc_program_pushArray(BcProgram *p, const char *restrict code, size_t *restrict bgn, uchar inst) { BcResult r, *operand; BcNum *num; BcBigDig temp; // Get the index of the array. r.d.loc.loc = bc_program_index(code, bgn); // Doing an array is easy; just set the result type and finish. if (inst == BC_INST_ARRAY) { r.t = BC_RESULT_ARRAY; bc_vec_push(&p->results, &r); return; } // Grab the top element of the results stack for the array index. bc_program_prep(p, &operand, &num, 0); temp = bc_num_bigdig(num); // Set the result. r.t = BC_RESULT_ARRAY_ELEM; r.d.loc.idx = (size_t) temp; BC_SIG_LOCK; // Pop the index and push the element. bc_vec_pop(&p->results); bc_vec_push(&p->results, &r); BC_SIG_UNLOCK; } #if BC_ENABLED /** * Executes an increment or decrement operator. This only handles postfix * inc/dec because the parser translates prefix inc/dec into an assignment where * the value is used. * @param p The program. * @param inst The instruction; whether to do an increment or decrement. */ static void bc_program_incdec(BcProgram *p, uchar inst) { BcResult *ptr, res, copy; BcNum *num; uchar inst2; bc_program_prep(p, &ptr, &num, 0); BC_SIG_LOCK; // We need a copy from *before* the operation. copy.t = BC_RESULT_TEMP; bc_num_createCopy(©.d.n, num); BC_SETJMP_LOCKED(exit); BC_SIG_UNLOCK; // Create the proper assignment. res.t = BC_RESULT_ONE; inst2 = BC_INST_ASSIGN_PLUS_NO_VAL + (inst & 0x01); bc_vec_push(&p->results, &res); bc_program_assign(p, inst2); BC_SIG_LOCK; bc_vec_push(&p->results, ©); BC_UNSETJMP; BC_SIG_UNLOCK; // No need to free the copy here because we pushed it onto the stack. return; exit: BC_SIG_MAYLOCK; bc_num_free(©.d.n); BC_LONGJMP_CONT; } /** * Executes a function call for bc. * @param p The program. * @param code The bytecode vector to pull the number of arguments and the * function index out of. * @param bgn An in/out parameter; the start of the indices in the bytecode * vector, and will be updated to point after the indices on * return. */ static void bc_program_call(BcProgram *p, const char *restrict code, size_t *restrict bgn) { BcInstPtr ip; size_t i, nargs; BcFunc *f; BcVec *v; BcAuto *a; BcResult *arg; // Pull the number of arguments out of the bytecode vector. nargs = bc_program_index(code, bgn); // Set up instruction pointer. ip.idx = 0; ip.func = bc_program_index(code, bgn); f = bc_vec_item(&p->fns, ip.func); // Error checking. if (BC_ERR(!f->code.len)) bc_verr(BC_ERR_EXEC_UNDEF_FUNC, f->name); if (BC_ERR(nargs != f->nparams)) bc_verr(BC_ERR_EXEC_PARAMS, f->nparams, nargs); // Set the length of the results stack. We discount the argument, of course. ip.len = p->results.len - nargs; assert(BC_PROG_STACK(&p->results, nargs)); // Prepare the globals' stacks. if (BC_G) bc_program_prepGlobals(p); // Push the arguments onto the stacks of their respective parameters. for (i = 0; i < nargs; ++i) { size_t j; bool last = true; arg = bc_vec_top(&p->results); if (BC_ERR(arg->t == BC_RESULT_VOID)) bc_err(BC_ERR_EXEC_VOID_VAL); // Get the corresponding parameter. a = bc_vec_item(&f->autos, nargs - 1 - i); // If I have already pushed to a var, I need to make sure I // get the previous version, not the already pushed one. This condition // must be true for that to even be possible. if (arg->t == BC_RESULT_VAR || arg->t == BC_RESULT_ARRAY) { // Loop through all of the previous parameters. for (j = 0; j < i && last; ++j) { BcAuto *aptr = bc_vec_item(&f->autos, nargs - 1 - j); // This condition is true if there is a previous parameter with // the same name *and* type because variables and arrays do not // interfere with each other. last = (arg->d.loc.loc != aptr->idx || (!aptr->type) != (arg->t == BC_RESULT_VAR)); } } // Actually push the value onto the parameter's stack. bc_program_copyToVar(p, a->idx, a->type, last); } BC_SIG_LOCK; // Push zeroes onto the stacks of the auto variables. for (; i < f->autos.len; ++i) { // Get the auto and its stack. a = bc_vec_item(&f->autos, i); v = bc_program_vec(p, a->idx, a->type); // If a variable, just push a 0; otherwise, push an array. if (a->type == BC_TYPE_VAR) { BcNum *n = bc_vec_pushEmpty(v); bc_num_init(n, BC_NUM_DEF_SIZE); } else { BcVec *v2; assert(a->type == BC_TYPE_ARRAY); v2 = bc_vec_pushEmpty(v); bc_array_init(v2, true); } } // Push the instruction pointer onto the execution stack. bc_vec_push(&p->stack, &ip); BC_SIG_UNLOCK; } /** * Executes a return instruction. * @param p The program. * @param inst The return instruction. bc can return void, and we need to know * if it is. */ static void bc_program_return(BcProgram *p, uchar inst) { BcResult *res; BcFunc *f; BcInstPtr *ip; size_t i, nresults; // Get the instruction pointer. ip = bc_vec_top(&p->stack); // Get the difference between the actual number of results and the number of // results the caller expects. nresults = p->results.len - ip->len; // If this isn't true, there was a missing call somewhere. assert(BC_PROG_STACK(&p->stack, 2)); // If this isn't true, the parser screwed by giving us no value when we // expected one, or giving us a value when we expected none. assert(BC_PROG_STACK(&p->results, ip->len + (inst == BC_INST_RET))); // Get the function we are returning from. f = bc_vec_item(&p->fns, ip->func); res = bc_program_prepResult(p); // If we are returning normally... if (inst == BC_INST_RET) { BcNum *num; BcResult *operand; // Prepare and copy the return value. bc_program_operand(p, &operand, &num, 1); if (BC_PROG_STR(num)) { // We need to set this because otherwise, it will be a // BC_RESULT_TEMP, and BC_RESULT_TEMP needs an actual number to make // it easier to do type checking. res->t = BC_RESULT_STR; memcpy(&res->d.n, num, sizeof(BcNum)); } else { BC_SIG_LOCK; bc_num_createCopy(&res->d.n, num); } } // Void is easy; set the result. else if (inst == BC_INST_RET_VOID) res->t = BC_RESULT_VOID; else { BC_SIG_LOCK; // If we get here, the instruction is for returning a zero, so do that. bc_num_init(&res->d.n, BC_NUM_DEF_SIZE); } BC_SIG_MAYUNLOCK; // We need to pop items off of the stacks of arguments and autos as well. for (i = 0; i < f->autos.len; ++i) { BcAuto *a = bc_vec_item(&f->autos, i); BcVec *v = bc_program_vec(p, a->idx, a->type); bc_vec_pop(v); } + BC_SIG_LOCK; + // When we retire, pop all of the unused results. bc_program_retire(p, 1, nresults); // Pop the globals, if necessary. if (BC_G) bc_program_popGlobals(p, false); // Pop the stack. This is what causes the function to actually "return." bc_vec_pop(&p->stack); + + BC_SIG_UNLOCK; } #endif // BC_ENABLED /** * Executes a builtin function. * @param p The program. * @param inst The builtin to execute. */ static void bc_program_builtin(BcProgram *p, uchar inst) { BcResult *opd, *res; BcNum *num; bool len = (inst == BC_INST_LENGTH); // Ensure we have a valid builtin. #if BC_ENABLE_EXTRA_MATH assert(inst >= BC_INST_LENGTH && inst <= BC_INST_IRAND); #else // BC_ENABLE_EXTRA_MATH assert(inst >= BC_INST_LENGTH && inst <= BC_INST_ABS); #endif // BC_ENABLE_EXTRA_MATH #ifndef BC_PROG_NO_STACK_CHECK // Check stack for dc. if (BC_IS_DC && BC_ERR(!BC_PROG_STACK(&p->results, 1))) bc_err(BC_ERR_EXEC_STACK); #endif // BC_PROG_NO_STACK_CHECK assert(BC_PROG_STACK(&p->results, 1)); res = bc_program_prepResult(p); bc_program_operand(p, &opd, &num, 1); assert(num != NULL); // We need to ensure that strings and arrays aren't passed to most builtins. // The scale function can take strings in dc. if (!len && (inst != BC_INST_SCALE_FUNC || BC_IS_BC)) bc_program_type_num(opd, num); // Square root is easy. if (inst == BC_INST_SQRT) bc_num_sqrt(num, &res->d.n, BC_PROG_SCALE(p)); // Absolute value is easy. else if (inst == BC_INST_ABS) { BC_SIG_LOCK; bc_num_createCopy(&res->d.n, num); BC_SIG_UNLOCK; BC_NUM_NEG_CLR_NP(res->d.n); } #if BC_ENABLE_EXTRA_MATH // irand() is easy. else if (inst == BC_INST_IRAND) { BC_SIG_LOCK; bc_num_init(&res->d.n, num->len - BC_NUM_RDX_VAL(num)); BC_SIG_UNLOCK; bc_num_irand(num, &res->d.n, &p->rng); } #endif // BC_ENABLE_EXTRA_MATH // Everything else is...not easy. else { BcBigDig val = 0; // Well, scale() is easy, but length() is not. if (len) { // If we are bc and we have an array... if (opd->t == BC_RESULT_ARRAY) { // Yes, this is one place where we need to cast the number from // bc_program_num() to a vector. BcVec *v = (BcVec*) num; #if BC_ENABLED // Dereference the array, if necessary. if (BC_IS_BC && v->size == sizeof(uchar)) v = bc_program_dereference(p, v); #endif // BC_ENABLED assert(v->size == sizeof(BcNum)); val = (BcBigDig) v->len; } else { // If the item is a string... if (!BC_PROG_NUM(opd, num)) { char *str; // Get the string, then get the length. str = bc_program_string(p, num); val = (BcBigDig) strlen(str); } else { // Calculate the length of the number. val = (BcBigDig) bc_num_len(num); } } } // Like I said; scale() is actually easy. It just also needs the integer // conversion that length() does. else if (BC_IS_BC || BC_PROG_NUM(opd, num)) val = (BcBigDig) bc_num_scale(num); BC_SIG_LOCK; // Create the result. bc_num_createFromBigdig(&res->d.n, val); BC_SIG_UNLOCK; } bc_program_retire(p, 1, 1); } /** * Executes a divmod. * @param p The program. */ static void bc_program_divmod(BcProgram *p) { BcResult *opd1, *opd2, *res, *res2; BcNum *n1, *n2; size_t req; // We grow first to avoid pointer invalidation. bc_vec_grow(&p->results, 2); // We don't need to update the pointer because // the capacity is enough due to the line above. res2 = bc_program_prepResult(p); res = bc_program_prepResult(p); // Prepare the operands. bc_program_binOpPrep(p, &opd1, &n1, &opd2, &n2, 2); req = bc_num_mulReq(n1, n2, BC_PROG_SCALE(p)); BC_SIG_LOCK; // Initialize the results. bc_num_init(&res->d.n, req); bc_num_init(&res2->d.n, req); BC_SIG_UNLOCK; // Execute. bc_num_divmod(n1, n2, &res2->d.n, &res->d.n, BC_PROG_SCALE(p)); bc_program_retire(p, 2, 2); } /** * Executes modular exponentiation. * @param p The program. */ static void bc_program_modexp(BcProgram *p) { BcResult *r1, *r2, *r3, *res; BcNum *n1, *n2, *n3; #if DC_ENABLED // Check the stack. if (BC_IS_DC && BC_ERR(!BC_PROG_STACK(&p->results, 3))) bc_err(BC_ERR_EXEC_STACK); #endif // DC_ENABLED assert(BC_PROG_STACK(&p->results, 3)); res = bc_program_prepResult(p); // Get the first operand and typecheck. bc_program_operand(p, &r1, &n1, 3); bc_program_type_num(r1, n1); // Get the last two operands. bc_program_binOpPrep(p, &r2, &n2, &r3, &n3, 1); // Make sure that the values have their pointers updated, if necessary. // Only array elements are possible because this is dc. if (r1->t == BC_RESULT_ARRAY_ELEM && (r1->t == r2->t || r1->t == r3->t)) n1 = bc_program_num(p, r1); BC_SIG_LOCK; bc_num_init(&res->d.n, n3->len); BC_SIG_UNLOCK; bc_num_modexp(n1, n2, n3, &res->d.n); bc_program_retire(p, 1, 3); } /** * Asciifies a number for dc. This is a helper for bc_program_asciify(). * @param p The program. * @param n The number to asciify. */ static uchar bc_program_asciifyNum(BcProgram *p, BcNum *n) { BcNum num; BcBigDig val; #ifndef NDEBUG // This is entirely to satisfy a useless scan-build error. val = 0; #endif // NDEBUG bc_num_clear(&num); BC_SETJMP(num_err); BC_SIG_LOCK; bc_num_createCopy(&num, n); BC_SIG_UNLOCK; // We want to clear the scale and sign for easy mod later. bc_num_truncate(&num, num.scale); BC_NUM_NEG_CLR_NP(num); // This is guaranteed to not have a divide by 0 // because strmb is equal to 256. bc_num_mod(&num, &p->strmb, &num, 0); // This is also guaranteed to not error because num is in the range // [0, UCHAR_MAX], which is definitely in range for a BcBigDig. And // it is not negative. val = bc_num_bigdig2(&num); num_err: BC_SIG_MAYLOCK; bc_num_free(&num); BC_LONGJMP_CONT; return (uchar) val; } /** * Executes the "asciify" command in dc. * @param p The program. * @param fidx The index of the current function. */ static void bc_program_asciify(BcProgram *p, size_t fidx) { BcResult *r, res; BcNum *n; char str[2], *str2; uchar c; size_t idx; // Check the stack. if (BC_ERR(!BC_PROG_STACK(&p->results, 1))) bc_err(BC_ERR_EXEC_STACK); assert(BC_PROG_STACK(&p->results, 1)); // Get the top of the results stack. bc_program_operand(p, &r, &n, 0); assert(n != NULL); // Asciify. if (BC_PROG_NUM(r, n)) c = bc_program_asciifyNum(p, n); else { // Get the string itself, then the first character. str2 = bc_program_string(p, n); c = (uchar) str2[0]; } // Fill the resulting string. str[0] = (char) c; str[1] = '\0'; // Add the string to the data structures. BC_SIG_LOCK; idx = bc_program_addString(p, str, fidx); BC_SIG_UNLOCK; // Set the result res.t = BC_RESULT_STR; bc_num_clear(&res.d.n); res.d.n.rdx = fidx; res.d.n.scale = idx; // Pop and push. bc_vec_pop(&p->results); bc_vec_push(&p->results, &res); } /** * Streams a number or a string to stdout. * @param p The program. */ static void bc_program_printStream(BcProgram *p) { BcResult *r; BcNum *n; // Check the stack. if (BC_ERR(!BC_PROG_STACK(&p->results, 1))) bc_err(BC_ERR_EXEC_STACK); assert(BC_PROG_STACK(&p->results, 1)); // Get the top of the results stack. bc_program_operand(p, &r, &n, 0); assert(n != NULL); // Stream appropriately. if (BC_PROG_NUM(r, n)) bc_num_stream(n); else bc_program_printChars(bc_program_string(p, n)); // Pop the operand. bc_vec_pop(&p->results); } #if DC_ENABLED /** * Gets the length of a register in dc and pushes it onto the results stack. * @param p The program. * @param code The bytecode vector to pull the register's index out of. * @param bgn An in/out parameter; the start of the index in the bytecode * vector, and will be updated to point after the index on return. */ static void bc_program_regStackLen(BcProgram *p, const char *restrict code, size_t *restrict bgn) { size_t idx = bc_program_index(code, bgn); BcVec *v = bc_program_vec(p, idx, BC_TYPE_VAR); bc_program_pushBigdig(p, (BcBigDig) v->len, BC_RESULT_TEMP); } /** * Pushes the length of the results stack onto the results stack. * @param p The program. */ static void bc_program_stackLen(BcProgram *p) { bc_program_pushBigdig(p, (BcBigDig) p->results.len, BC_RESULT_TEMP); } /** * Pops a certain number of elements off the execution stack. * @param p The program. * @param inst The instruction to tell us how many. There is one to pop up to * 2, and one to pop the amount equal to the number at the top of * the results stack. */ static void bc_program_nquit(BcProgram *p, uchar inst) { BcResult *opnd; BcNum *num; BcBigDig val; size_t i; // Ensure that the tail calls stack is correct. assert(p->stack.len == p->tail_calls.len); // Get the number of executions to pop. if (inst == BC_INST_QUIT) val = 2; else { bc_program_prep(p, &opnd, &num, 0); val = bc_num_bigdig(num); bc_vec_pop(&p->results); } // Loop over the tail call stack and adjust the quit value appropriately. for (i = 0; val && i < p->tail_calls.len; ++i) { // Get the number of tail calls for this one. size_t calls = *((size_t*) bc_vec_item_rev(&p->tail_calls, i)) + 1; // Adjust the value. if (calls >= val) val = 0; else val -= (BcBigDig) calls; } // If we don't have enough executions, just quit. if (i == p->stack.len) { vm.status = BC_STATUS_QUIT; BC_JMP; } else { // We can always pop the last item we reached on the tail call stack // because these are for tail calls. That means that any executions that // we would not have quit in that position on the stack would have quit // anyway. + BC_SIG_LOCK; bc_vec_npop(&p->stack, i); bc_vec_npop(&p->tail_calls, i); + BC_SIG_UNLOCK; } } /** * Pushes the depth of the execution stack onto the stack. * @param p The program. */ static void bc_program_execStackLen(BcProgram *p) { size_t i, amt, len = p->tail_calls.len; amt = len; for (i = 0; i < len; ++i) amt += *((size_t*) bc_vec_item(&p->tail_calls, i)); bc_program_pushBigdig(p, (BcBigDig) amt, BC_RESULT_TEMP); } /** * * @param p The program. * @param code The bytecode vector to pull the register's index out of. * @param bgn An in/out parameter; the start of the index in the bytecode * vector, and will be updated to point after the index on return. * @param cond True if the execution is conditional, false otherwise. * @param len The number of bytes in the bytecode vector. */ static void bc_program_execStr(BcProgram *p, const char *restrict code, size_t *restrict bgn, bool cond, size_t len) { BcResult *r; char *str; BcFunc *f; BcInstPtr ip; size_t fidx; BcNum *n; assert(p->stack.len == p->tail_calls.len); // Check the stack. if (BC_ERR(!BC_PROG_STACK(&p->results, 1))) bc_err(BC_ERR_EXEC_STACK); assert(BC_PROG_STACK(&p->results, 1)); // Get the operand. bc_program_operand(p, &r, &n, 0); // If execution is conditional... if (cond) { bool exec; size_t idx, then_idx, else_idx; // Get the index of the "then" var and "else" var. then_idx = bc_program_index(code, bgn); else_idx = bc_program_index(code, bgn); // Figure out if we should execute. exec = (r->d.n.len != 0); idx = exec ? then_idx : else_idx; BC_SIG_LOCK; BC_SETJMP_LOCKED(exit); // If we are supposed to execute, execute. If else_idx == SIZE_MAX, that // means there was no else clause, so if execute is false and else does // not exist, we don't execute. The goto skips all of the setup for the // execution. if (exec || (else_idx != SIZE_MAX)) n = bc_vec_top(bc_program_vec(p, idx, BC_TYPE_VAR)); else goto exit; if (BC_ERR(!BC_PROG_STR(n))) bc_err(BC_ERR_EXEC_TYPE); BC_UNSETJMP; BC_SIG_UNLOCK; } else { // In non-conditional situations, only the top of stack can be executed, // and in those cases, variables are not allowed to be "on the stack"; // they are only put on the stack to be assigned to. assert(r->t != BC_RESULT_VAR); if (r->t != BC_RESULT_STR) return; } assert(BC_PROG_STR(n)); // Get the string. str = bc_program_string(p, n); // Get the function index and function. BC_SIG_LOCK; fidx = bc_program_insertFunc(p, str); BC_SIG_UNLOCK; f = bc_vec_item(&p->fns, fidx); // If the function has not been parsed yet... if (!f->code.len) { BC_SIG_LOCK; if (!BC_PARSE_IS_INITED(&vm.read_prs, p)) { bc_parse_init(&vm.read_prs, p, fidx); // Initialize this too because bc_vm_shutdown() expects them to be // initialized togther. bc_vec_init(&vm.read_buf, sizeof(char), BC_DTOR_NONE); } // This needs to be updated because the parser could have been used // somewhere else else bc_parse_updateFunc(&vm.read_prs, fidx); bc_lex_file(&vm.read_prs.l, vm.file); BC_SETJMP_LOCKED(err); BC_SIG_UNLOCK; // Parse. bc_parse_text(&vm.read_prs, str, false); - vm.expr(&vm.read_prs, BC_PARSE_NOCALL); BC_SIG_LOCK; + vm.expr(&vm.read_prs, BC_PARSE_NOCALL); BC_UNSETJMP; // We can just assert this here because // dc should parse everything until EOF. assert(vm.read_prs.l.t == BC_LEX_EOF); BC_SIG_UNLOCK; } // Set the instruction pointer. ip.idx = 0; ip.len = p->results.len; ip.func = fidx; + BC_SIG_LOCK; + // Pop the operand. bc_vec_pop(&p->results); // Tail call processing. This condition means that there is more on the // execution stack, and we are at the end of the bytecode vector, and the // last instruction is just a BC_INST_POP_EXEC, which would return. if (p->stack.len > 1 && *bgn == len - 1 && code[*bgn] == BC_INST_POP_EXEC) { size_t *call_ptr = bc_vec_top(&p->tail_calls); // Add one to the tail call. *call_ptr += 1; // Pop the execution stack before pushing the new instruction pointer // on. bc_vec_pop(&p->stack); } // If not a tail call, just push a new one. else bc_vec_push(&p->tail_calls, &ip.idx); // Push the new function onto the execution stack and return. bc_vec_push(&p->stack, &ip); + BC_SIG_UNLOCK; + return; err: BC_SIG_MAYLOCK; f = bc_vec_item(&p->fns, fidx); // Make sure to erase the bytecode vector so dc knows it is not parsed. bc_vec_popAll(&f->code); exit: bc_vec_pop(&p->results); BC_LONGJMP_CONT; } /** * Prints every item on the results stack, one per line. * @param p The program. */ static void bc_program_printStack(BcProgram *p) { size_t idx; for (idx = 0; idx < p->results.len; ++idx) bc_program_print(p, BC_INST_PRINT, idx); } #endif // DC_ENABLED /** * Pushes the value of a global onto the results stack. * @param p The program. * @param inst Which global to push, as an instruction. */ static void bc_program_pushGlobal(BcProgram *p, uchar inst) { BcResultType t; // Make sure the instruction is valid. assert(inst >= BC_INST_IBASE && inst <= BC_INST_SCALE); // Push the global. t = inst - BC_INST_IBASE + BC_RESULT_IBASE; bc_program_pushBigdig(p, p->globals[inst - BC_INST_IBASE], t); } /** * Pushes the value of a global setting onto the stack. * @param p The program. * @param inst Which global setting to push, as an instruction. */ static void bc_program_globalSetting(BcProgram *p, uchar inst) { BcBigDig val; // Make sure the instruction is valid. assert(inst >= BC_INST_LINE_LENGTH && inst <= BC_INST_LEADING_ZERO); if (inst == BC_INST_LINE_LENGTH) val = (BcBigDig) vm.line_len; #if BC_ENABLED else if (inst == BC_INST_GLOBAL_STACKS) val = (BC_G != 0); #endif // BC_ENABLED else val = (BC_Z != 0); // Push the global. bc_program_pushBigdig(p, val, BC_RESULT_TEMP); } #if BC_ENABLE_EXTRA_MATH /** * Pushes the value of seed on the stack. * @param p The program. */ static void bc_program_pushSeed(BcProgram *p) { BcResult *res; res = bc_program_prepResult(p); res->t = BC_RESULT_SEED; BC_SIG_LOCK; // We need 2*BC_RAND_NUM_SIZE because of the size of the state. bc_num_init(&res->d.n, 2 * BC_RAND_NUM_SIZE); BC_SIG_UNLOCK; bc_num_createFromRNG(&res->d.n, &p->rng); } #endif // BC_ENABLE_EXTRA_MATH /** * Adds a function to the fns array. The function's ID must have already been * inserted into the map. * @param p The program. * @param id_ptr The ID of the function as inserted into the map. */ static void bc_program_addFunc(BcProgram *p, BcId *id_ptr) { BcInstPtr *ip; BcFunc *f; BC_SIG_ASSERT_LOCKED; // Push and init. f = bc_vec_pushEmpty(&p->fns); bc_func_init(f, id_ptr->name); // This is to make sure pointers are updated if the array was moved. if (p->stack.len) { ip = bc_vec_top(&p->stack); bc_program_setVecs(p, (BcFunc*) bc_vec_item(&p->fns, ip->func)); } } size_t bc_program_insertFunc(BcProgram *p, const char *name) { BcId *id_ptr; bool new; size_t idx; BC_SIG_ASSERT_LOCKED; assert(p != NULL && name != NULL); // Insert into the map and get the resulting ID. new = bc_map_insert(&p->fn_map, name, p->fns.len, &idx); id_ptr = (BcId*) bc_vec_item(&p->fn_map, idx); idx = id_ptr->idx; // If the function is new... if (new) { // Add the function to the fns array. bc_program_addFunc(p, id_ptr); } #if BC_ENABLED // bc has to reset the function because it's about to be redefined. else if (BC_IS_BC) { BcFunc *func = bc_vec_item(&p->fns, idx); bc_func_reset(func); } #endif // BC_ENABLED return idx; } #ifndef NDEBUG void bc_program_free(BcProgram *p) { size_t i; BC_SIG_ASSERT_LOCKED; assert(p != NULL); // Free the globals stacks. for (i = 0; i < BC_PROG_GLOBALS_LEN; ++i) bc_vec_free(p->globals_v + i); bc_vec_free(&p->fns); bc_vec_free(&p->fn_map); bc_vec_free(&p->vars); bc_vec_free(&p->var_map); bc_vec_free(&p->arrs); bc_vec_free(&p->arr_map); bc_vec_free(&p->results); bc_vec_free(&p->stack); #if BC_ENABLED if (BC_IS_BC) bc_num_free(&p->last); #endif // BC_ENABLED #if BC_ENABLE_EXTRA_MATH bc_rand_free(&p->rng); #endif // BC_ENABLE_EXTRA_MATH #if DC_ENABLED if (BC_IS_DC) bc_vec_free(&p->tail_calls); #endif // DC_ENABLED } #endif // NDEBUG void bc_program_init(BcProgram *p) { BcInstPtr ip; size_t i; BC_SIG_ASSERT_LOCKED; assert(p != NULL); // We want this clear. memset(&ip, 0, sizeof(BcInstPtr)); // Setup the globals stacks and the current values. for (i = 0; i < BC_PROG_GLOBALS_LEN; ++i) { BcBigDig val = i == BC_PROG_GLOBALS_SCALE ? 0 : BC_BASE; bc_vec_init(p->globals_v + i, sizeof(BcBigDig), BC_DTOR_NONE); bc_vec_push(p->globals_v + i, &val); p->globals[i] = val; } #if DC_ENABLED // dc-only setup. if (BC_IS_DC) { bc_vec_init(&p->tail_calls, sizeof(size_t), BC_DTOR_NONE); // We want an item for the main function on the tail call stack. i = 0; bc_vec_push(&p->tail_calls, &i); } #endif // DC_ENABLED bc_num_setup(&p->strmb, p->strmb_num, BC_NUM_BIGDIG_LOG10); bc_num_bigdig2num(&p->strmb, BC_NUM_STREAM_BASE); #if BC_ENABLE_EXTRA_MATH // We need to initialize srand() just in case /dev/urandom and /dev/random // are not available. srand((unsigned int) time(NULL)); bc_rand_init(&p->rng); #endif // BC_ENABLE_EXTRA_MATH #if BC_ENABLED if (BC_IS_BC) bc_num_init(&p->last, BC_NUM_DEF_SIZE); #endif // BC_ENABLED #ifndef NDEBUG bc_vec_init(&p->fns, sizeof(BcFunc), BC_DTOR_FUNC); #else // NDEBUG bc_vec_init(&p->fns, sizeof(BcFunc), BC_DTOR_NONE); #endif // NDEBUG bc_map_init(&p->fn_map); bc_program_insertFunc(p, bc_func_main); bc_program_insertFunc(p, bc_func_read); bc_vec_init(&p->vars, sizeof(BcVec), BC_DTOR_VEC); bc_map_init(&p->var_map); bc_vec_init(&p->arrs, sizeof(BcVec), BC_DTOR_VEC); bc_map_init(&p->arr_map); bc_vec_init(&p->results, sizeof(BcResult), BC_DTOR_RESULT); // Push the first instruction pointer onto the execution stack. bc_vec_init(&p->stack, sizeof(BcInstPtr), BC_DTOR_NONE); bc_vec_push(&p->stack, &ip); // Make sure the pointers are properly set up. bc_program_setVecs(p, (BcFunc*) bc_vec_item(&p->fns, BC_PROG_MAIN)); assert(p->consts != NULL && p->strs != NULL); } void bc_program_reset(BcProgram *p) { BcFunc *f; BcInstPtr *ip; BC_SIG_ASSERT_LOCKED; // Pop all but the last execution and all results. bc_vec_npop(&p->stack, p->stack.len - 1); bc_vec_popAll(&p->results); #if BC_ENABLED // Clear the globals' stacks. if (BC_G) bc_program_popGlobals(p, true); #endif // BC_ENABLED // Clear the bytecode vector of the main function. f = bc_vec_item(&p->fns, BC_PROG_MAIN); bc_vec_npop(&f->code, f->code.len); // Reset the instruction pointer. ip = bc_vec_top(&p->stack); bc_program_setVecs(p, f); memset(ip, 0, sizeof(BcInstPtr)); // Write the ready message for a signal, and clear the signal. if (vm.sig) { bc_file_write(&vm.fout, bc_flush_none, bc_program_ready_msg, bc_program_ready_msg_len); bc_file_flush(&vm.fout, bc_flush_err); vm.sig = 0; } } void bc_program_exec(BcProgram *p) { size_t idx; BcResult r, *ptr; BcInstPtr *ip; BcFunc *func; char *code; bool cond = false; uchar inst; #if BC_ENABLED BcNum *num; #endif // BC_ENABLED #if !BC_HAS_COMPUTED_GOTO #ifndef NDEBUG size_t jmp_bufs_len; #endif // NDEBUG #endif // !BC_HAS_COMPUTED_GOTO #if BC_HAS_COMPUTED_GOTO BC_PROG_LBLS; BC_PROG_LBLS_ASSERT; // BC_INST_INVALID is a marker for the end so that we don't have to have an // execution loop. func = (BcFunc*) bc_vec_item(&p->fns, BC_PROG_MAIN); bc_vec_pushByte(&func->code, BC_INST_INVALID); #endif // BC_HAS_COMPUTED_GOTO ip = bc_vec_top(&p->stack); func = (BcFunc*) bc_vec_item(&p->fns, ip->func); code = func->code.v; // Ensure the pointers are correct. + BC_SIG_LOCK; bc_program_setVecs(p, func); + BC_SIG_UNLOCK; #if !BC_HAS_COMPUTED_GOTO #ifndef NDEBUG jmp_bufs_len = vm.jmp_bufs.len; #endif // NDEBUG // This loop is the heart of the execution engine. It *is* the engine. For // computed goto, it is ignored. while (ip->idx < func->code.len) #endif // !BC_HAS_COMPUTED_GOTO { BC_SIG_ASSERT_NOT_LOCKED; #if BC_HAS_COMPUTED_GOTO BC_PROG_JUMP(inst, code, ip); #else // BC_HAS_COMPUTED_GOTO // Get the next instruction and increment the index. inst = (uchar) code[(ip->idx)++]; #endif // BC_HAS_COMPUTED_GOTO #if BC_DEBUG_CODE bc_file_printf(&vm.ferr, "inst: %s\n", bc_inst_names[inst]); bc_file_flush(&vm.ferr, bc_flush_none); #endif // BC_DEBUG_CODE #if !BC_HAS_COMPUTED_GOTO switch (inst) #endif // !BC_HAS_COMPUTED_GOTO { #if BC_ENABLED // This just sets up the condition for the unconditional jump below, // which checks the condition, if necessary. BC_PROG_LBL(BC_INST_JUMP_ZERO): { bc_program_prep(p, &ptr, &num, 0); cond = !bc_num_cmpZero(num); bc_vec_pop(&p->results); BC_PROG_DIRECT_JUMP(BC_INST_JUMP) } // Fallthrough. BC_PROG_FALLTHROUGH BC_PROG_LBL(BC_INST_JUMP): { idx = bc_program_index(code, &ip->idx); // If a jump is required... if (inst == BC_INST_JUMP || cond) { // Get the address to jump to. size_t *addr = bc_vec_item(&func->labels, idx); // If this fails, then the parser failed to set up the // labels correctly. assert(*addr != SIZE_MAX); // Set the new address. ip->idx = *addr; } BC_PROG_JUMP(inst, code, ip); } BC_PROG_LBL(BC_INST_CALL): { assert(BC_IS_BC); bc_program_call(p, code, &ip->idx); // Because we changed the execution stack and where we are // executing, we have to update all of this. + BC_SIG_LOCK; ip = bc_vec_top(&p->stack); func = bc_vec_item(&p->fns, ip->func); code = func->code.v; bc_program_setVecs(p, func); + BC_SIG_UNLOCK; BC_PROG_JUMP(inst, code, ip); } BC_PROG_LBL(BC_INST_INC): BC_PROG_LBL(BC_INST_DEC): { bc_program_incdec(p, inst); BC_PROG_JUMP(inst, code, ip); } BC_PROG_LBL(BC_INST_HALT): { vm.status = BC_STATUS_QUIT; // Just jump out. The jump series will take care of everything. BC_JMP; BC_PROG_JUMP(inst, code, ip); } BC_PROG_LBL(BC_INST_RET): BC_PROG_LBL(BC_INST_RET0): BC_PROG_LBL(BC_INST_RET_VOID): { bc_program_return(p, inst); // Because we changed the execution stack and where we are // executing, we have to update all of this. + BC_SIG_LOCK; ip = bc_vec_top(&p->stack); func = bc_vec_item(&p->fns, ip->func); code = func->code.v; bc_program_setVecs(p, func); + BC_SIG_UNLOCK; BC_PROG_JUMP(inst, code, ip); } #endif // BC_ENABLED BC_PROG_LBL(BC_INST_BOOL_OR): BC_PROG_LBL(BC_INST_BOOL_AND): BC_PROG_LBL(BC_INST_REL_EQ): BC_PROG_LBL(BC_INST_REL_LE): BC_PROG_LBL(BC_INST_REL_GE): BC_PROG_LBL(BC_INST_REL_NE): BC_PROG_LBL(BC_INST_REL_LT): BC_PROG_LBL(BC_INST_REL_GT): { bc_program_logical(p, inst); BC_PROG_JUMP(inst, code, ip); } BC_PROG_LBL(BC_INST_READ): { // We want to flush output before // this in case there is a prompt. bc_file_flush(&vm.fout, bc_flush_save); bc_program_read(p); // Because we changed the execution stack and where we are // executing, we have to update all of this. + BC_SIG_LOCK; ip = bc_vec_top(&p->stack); func = bc_vec_item(&p->fns, ip->func); code = func->code.v; bc_program_setVecs(p, func); + BC_SIG_UNLOCK; BC_PROG_JUMP(inst, code, ip); } #if BC_ENABLE_EXTRA_MATH BC_PROG_LBL(BC_INST_RAND): { bc_program_rand(p); BC_PROG_JUMP(inst, code, ip); } #endif // BC_ENABLE_EXTRA_MATH BC_PROG_LBL(BC_INST_MAXIBASE): BC_PROG_LBL(BC_INST_MAXOBASE): BC_PROG_LBL(BC_INST_MAXSCALE): #if BC_ENABLE_EXTRA_MATH BC_PROG_LBL(BC_INST_MAXRAND): #endif // BC_ENABLE_EXTRA_MATH { BcBigDig dig = vm.maxes[inst - BC_INST_MAXIBASE]; bc_program_pushBigdig(p, dig, BC_RESULT_TEMP); BC_PROG_JUMP(inst, code, ip); } BC_PROG_LBL(BC_INST_LINE_LENGTH): #if BC_ENABLED BC_PROG_LBL(BC_INST_GLOBAL_STACKS): #endif // BC_ENABLED BC_PROG_LBL(BC_INST_LEADING_ZERO): { bc_program_globalSetting(p, inst); BC_PROG_JUMP(inst, code, ip); } BC_PROG_LBL(BC_INST_VAR): { bc_program_pushVar(p, code, &ip->idx, false, false); BC_PROG_JUMP(inst, code, ip); } BC_PROG_LBL(BC_INST_ARRAY_ELEM): BC_PROG_LBL(BC_INST_ARRAY): { bc_program_pushArray(p, code, &ip->idx, inst); BC_PROG_JUMP(inst, code, ip); } BC_PROG_LBL(BC_INST_IBASE): BC_PROG_LBL(BC_INST_SCALE): BC_PROG_LBL(BC_INST_OBASE): { bc_program_pushGlobal(p, inst); BC_PROG_JUMP(inst, code, ip); } #if BC_ENABLE_EXTRA_MATH BC_PROG_LBL(BC_INST_SEED): { bc_program_pushSeed(p); BC_PROG_JUMP(inst, code, ip); } #endif // BC_ENABLE_EXTRA_MATH BC_PROG_LBL(BC_INST_LENGTH): BC_PROG_LBL(BC_INST_SCALE_FUNC): BC_PROG_LBL(BC_INST_SQRT): BC_PROG_LBL(BC_INST_ABS): #if BC_ENABLE_EXTRA_MATH BC_PROG_LBL(BC_INST_IRAND): #endif // BC_ENABLE_EXTRA_MATH { bc_program_builtin(p, inst); BC_PROG_JUMP(inst, code, ip); } BC_PROG_LBL(BC_INST_ASCIIFY): { bc_program_asciify(p, ip->func); // Because we changed the execution stack and where we are // executing, we have to update all of this. + BC_SIG_LOCK; ip = bc_vec_top(&p->stack); func = bc_vec_item(&p->fns, ip->func); code = func->code.v; bc_program_setVecs(p, func); + BC_SIG_UNLOCK; BC_PROG_JUMP(inst, code, ip); } BC_PROG_LBL(BC_INST_NUM): { bc_program_const(p, code, &ip->idx); BC_PROG_JUMP(inst, code, ip); } BC_PROG_LBL(BC_INST_ZERO): BC_PROG_LBL(BC_INST_ONE): #if BC_ENABLED BC_PROG_LBL(BC_INST_LAST): #endif // BC_ENABLED { r.t = BC_RESULT_ZERO + (inst - BC_INST_ZERO); bc_vec_push(&p->results, &r); BC_PROG_JUMP(inst, code, ip); } BC_PROG_LBL(BC_INST_PRINT): BC_PROG_LBL(BC_INST_PRINT_POP): #if BC_ENABLED BC_PROG_LBL(BC_INST_PRINT_STR): #endif // BC_ENABLED { bc_program_print(p, inst, 0); // We want to flush right away to save the output for history, // if history must preserve it when taking input. bc_file_flush(&vm.fout, bc_flush_save); BC_PROG_JUMP(inst, code, ip); } BC_PROG_LBL(BC_INST_STR): { // Set up the result and push. r.t = BC_RESULT_STR; bc_num_clear(&r.d.n); r.d.n.rdx = bc_program_index(code, &ip->idx); r.d.n.scale = bc_program_index(code, &ip->idx); bc_vec_push(&p->results, &r); BC_PROG_JUMP(inst, code, ip); } BC_PROG_LBL(BC_INST_POWER): BC_PROG_LBL(BC_INST_MULTIPLY): BC_PROG_LBL(BC_INST_DIVIDE): BC_PROG_LBL(BC_INST_MODULUS): BC_PROG_LBL(BC_INST_PLUS): BC_PROG_LBL(BC_INST_MINUS): #if BC_ENABLE_EXTRA_MATH BC_PROG_LBL(BC_INST_PLACES): BC_PROG_LBL(BC_INST_LSHIFT): BC_PROG_LBL(BC_INST_RSHIFT): #endif // BC_ENABLE_EXTRA_MATH { bc_program_op(p, inst); BC_PROG_JUMP(inst, code, ip); } BC_PROG_LBL(BC_INST_NEG): BC_PROG_LBL(BC_INST_BOOL_NOT): #if BC_ENABLE_EXTRA_MATH BC_PROG_LBL(BC_INST_TRUNC): #endif // BC_ENABLE_EXTRA_MATH { bc_program_unary(p, inst); BC_PROG_JUMP(inst, code, ip); } #if BC_ENABLED BC_PROG_LBL(BC_INST_ASSIGN_POWER): BC_PROG_LBL(BC_INST_ASSIGN_MULTIPLY): BC_PROG_LBL(BC_INST_ASSIGN_DIVIDE): BC_PROG_LBL(BC_INST_ASSIGN_MODULUS): BC_PROG_LBL(BC_INST_ASSIGN_PLUS): BC_PROG_LBL(BC_INST_ASSIGN_MINUS): #if BC_ENABLE_EXTRA_MATH BC_PROG_LBL(BC_INST_ASSIGN_PLACES): BC_PROG_LBL(BC_INST_ASSIGN_LSHIFT): BC_PROG_LBL(BC_INST_ASSIGN_RSHIFT): #endif // BC_ENABLE_EXTRA_MATH BC_PROG_LBL(BC_INST_ASSIGN): BC_PROG_LBL(BC_INST_ASSIGN_POWER_NO_VAL): BC_PROG_LBL(BC_INST_ASSIGN_MULTIPLY_NO_VAL): BC_PROG_LBL(BC_INST_ASSIGN_DIVIDE_NO_VAL): BC_PROG_LBL(BC_INST_ASSIGN_MODULUS_NO_VAL): BC_PROG_LBL(BC_INST_ASSIGN_PLUS_NO_VAL): BC_PROG_LBL(BC_INST_ASSIGN_MINUS_NO_VAL): #if BC_ENABLE_EXTRA_MATH BC_PROG_LBL(BC_INST_ASSIGN_PLACES_NO_VAL): BC_PROG_LBL(BC_INST_ASSIGN_LSHIFT_NO_VAL): BC_PROG_LBL(BC_INST_ASSIGN_RSHIFT_NO_VAL): #endif // BC_ENABLE_EXTRA_MATH #endif // BC_ENABLED BC_PROG_LBL(BC_INST_ASSIGN_NO_VAL): { bc_program_assign(p, inst); BC_PROG_JUMP(inst, code, ip); } BC_PROG_LBL(BC_INST_POP): { #ifndef BC_PROG_NO_STACK_CHECK // dc must do a stack check, but bc does not. if (BC_IS_DC) { if (BC_ERR(!BC_PROG_STACK(&p->results, 1))) bc_err(BC_ERR_EXEC_STACK); } #endif // BC_PROG_NO_STACK_CHECK assert(BC_PROG_STACK(&p->results, 1)); bc_vec_pop(&p->results); BC_PROG_JUMP(inst, code, ip); } BC_PROG_LBL(BC_INST_SWAP): { BcResult *ptr2; // Check the stack. if (BC_ERR(!BC_PROG_STACK(&p->results, 2))) bc_err(BC_ERR_EXEC_STACK); assert(BC_PROG_STACK(&p->results, 2)); // Get the two items. ptr = bc_vec_item_rev(&p->results, 0); ptr2 = bc_vec_item_rev(&p->results, 1); // Swap. It's just easiest to do it this way. memcpy(&r, ptr, sizeof(BcResult)); memcpy(ptr, ptr2, sizeof(BcResult)); memcpy(ptr2, &r, sizeof(BcResult)); BC_PROG_JUMP(inst, code, ip); } BC_PROG_LBL(BC_INST_MODEXP): { bc_program_modexp(p); BC_PROG_JUMP(inst, code, ip); } BC_PROG_LBL(BC_INST_DIVMOD): { bc_program_divmod(p); BC_PROG_JUMP(inst, code, ip); } BC_PROG_LBL(BC_INST_PRINT_STREAM): { bc_program_printStream(p); BC_PROG_JUMP(inst, code, ip); } #if DC_ENABLED BC_PROG_LBL(BC_INST_POP_EXEC): { // If this fails, the dc parser got something wrong. assert(BC_PROG_STACK(&p->stack, 2)); // Pop the execution stack and tail call stack. bc_vec_pop(&p->stack); bc_vec_pop(&p->tail_calls); // Because we changed the execution stack and where we are // executing, we have to update all of this. + BC_SIG_LOCK; ip = bc_vec_top(&p->stack); func = bc_vec_item(&p->fns, ip->func); code = func->code.v; bc_program_setVecs(p, func); + BC_SIG_UNLOCK; BC_PROG_JUMP(inst, code, ip); } BC_PROG_LBL(BC_INST_EXECUTE): BC_PROG_LBL(BC_INST_EXEC_COND): { cond = (inst == BC_INST_EXEC_COND); bc_program_execStr(p, code, &ip->idx, cond, func->code.len); // Because we changed the execution stack and where we are // executing, we have to update all of this. + BC_SIG_LOCK; ip = bc_vec_top(&p->stack); func = bc_vec_item(&p->fns, ip->func); code = func->code.v; bc_program_setVecs(p, func); + BC_SIG_UNLOCK; BC_PROG_JUMP(inst, code, ip); } BC_PROG_LBL(BC_INST_PRINT_STACK): { bc_program_printStack(p); BC_PROG_JUMP(inst, code, ip); } BC_PROG_LBL(BC_INST_CLEAR_STACK): { bc_vec_popAll(&p->results); BC_PROG_JUMP(inst, code, ip); } BC_PROG_LBL(BC_INST_REG_STACK_LEN): { bc_program_regStackLen(p, code, &ip->idx); BC_PROG_JUMP(inst, code, ip); } BC_PROG_LBL(BC_INST_STACK_LEN): { bc_program_stackLen(p); BC_PROG_JUMP(inst, code, ip); } BC_PROG_LBL(BC_INST_DUPLICATE): { // Check the stack. if (BC_ERR(!BC_PROG_STACK(&p->results, 1))) bc_err(BC_ERR_EXEC_STACK); assert(BC_PROG_STACK(&p->results, 1)); // Get the top of the stack. ptr = bc_vec_top(&p->results); BC_SIG_LOCK; // Copy and push. bc_result_copy(&r, ptr); bc_vec_push(&p->results, &r); BC_SIG_UNLOCK; BC_PROG_JUMP(inst, code, ip); } BC_PROG_LBL(BC_INST_LOAD): BC_PROG_LBL(BC_INST_PUSH_VAR): { bool copy = (inst == BC_INST_LOAD); bc_program_pushVar(p, code, &ip->idx, true, copy); BC_PROG_JUMP(inst, code, ip); } BC_PROG_LBL(BC_INST_PUSH_TO_VAR): { idx = bc_program_index(code, &ip->idx); bc_program_copyToVar(p, idx, BC_TYPE_VAR, true); BC_PROG_JUMP(inst, code, ip); } BC_PROG_LBL(BC_INST_QUIT): BC_PROG_LBL(BC_INST_NQUIT): { bc_program_nquit(p, inst); // Because we changed the execution stack and where we are // executing, we have to update all of this. + BC_SIG_LOCK; ip = bc_vec_top(&p->stack); func = bc_vec_item(&p->fns, ip->func); code = func->code.v; bc_program_setVecs(p, func); + BC_SIG_UNLOCK; BC_PROG_JUMP(inst, code, ip); } BC_PROG_LBL(BC_INST_EXEC_STACK_LEN): { bc_program_execStackLen(p); BC_PROG_JUMP(inst, code, ip); } #endif // DC_ENABLED #if BC_HAS_COMPUTED_GOTO BC_PROG_LBL(BC_INST_INVALID): { return; } #else // BC_HAS_COMPUTED_GOTO default: { BC_UNREACHABLE #ifndef NDEBUG abort(); #endif // NDEBUG } #endif // BC_HAS_COMPUTED_GOTO } #if !BC_HAS_COMPUTED_GOTO #ifndef NDEBUG // This is to allow me to use a debugger to see the last instruction, // which will point to which function was the problem. But it's also a // good smoke test for error handling changes. assert(jmp_bufs_len == vm.jmp_bufs.len); #endif // NDEBUG #endif // !BC_HAS_COMPUTED_GOTO } } #if BC_DEBUG_CODE #if BC_ENABLED && DC_ENABLED void bc_program_printStackDebug(BcProgram *p) { bc_file_puts(&vm.fout, bc_flush_err, "-------------- Stack ----------\n"); bc_program_printStack(p); bc_file_puts(&vm.fout, bc_flush_err, "-------------- Stack End ------\n"); } static void bc_program_printIndex(const char *restrict code, size_t *restrict bgn) { uchar byte, i, bytes = (uchar) code[(*bgn)++]; ulong val = 0; for (byte = 1, i = 0; byte && i < bytes; ++i) { byte = (uchar) code[(*bgn)++]; if (byte) val |= ((ulong) byte) << (CHAR_BIT * i); } bc_vm_printf(" (%lu) ", val); } static void bc_program_printStr(const BcProgram *p, const char *restrict code, size_t *restrict bgn) { size_t idx = bc_program_index(code, bgn); char *s; s = *((char**) bc_vec_item(p->strs, idx)); bc_vm_printf(" (\"%s\") ", s); } void bc_program_printInst(const BcProgram *p, const char *restrict code, size_t *restrict bgn) { uchar inst = (uchar) code[(*bgn)++]; bc_vm_printf("Inst[%zu]: %s [%lu]; ", *bgn - 1, bc_inst_names[inst], (unsigned long) inst); if (inst == BC_INST_VAR || inst == BC_INST_ARRAY_ELEM || inst == BC_INST_ARRAY) { bc_program_printIndex(code, bgn); } else if (inst == BC_INST_STR) bc_program_printStr(p, code, bgn); else if (inst == BC_INST_NUM) { size_t idx = bc_program_index(code, bgn); BcConst *c = bc_vec_item(p->consts, idx); bc_vm_printf("(%s)", c->val); } else if (inst == BC_INST_CALL || (inst > BC_INST_STR && inst <= BC_INST_JUMP_ZERO)) { bc_program_printIndex(code, bgn); if (inst == BC_INST_CALL) bc_program_printIndex(code, bgn); } bc_vm_putchar('\n', bc_flush_err); } void bc_program_code(const BcProgram* p) { BcFunc *f; char *code; BcInstPtr ip; size_t i; for (i = 0; i < p->fns.len; ++i) { ip.idx = ip.len = 0; ip.func = i; f = bc_vec_item(&p->fns, ip.func); code = f->code.v; bc_vm_printf("func[%zu]:\n", ip.func); while (ip.idx < f->code.len) bc_program_printInst(p, code, &ip.idx); bc_file_puts(&vm.fout, bc_flush_err, "\n\n"); } } #endif // BC_ENABLED && DC_ENABLED #endif // BC_DEBUG_CODE diff --git a/contrib/bc/src/rand.c b/contrib/bc/src/rand.c index bfc79be7cfb9..a3b8942a6042 100644 --- a/contrib/bc/src/rand.c +++ b/contrib/bc/src/rand.c @@ -1,581 +1,586 @@ /* * ***************************************************************************** * * Parts of this code are adapted from the following: * * PCG, A Family of Better Random Number Generators. * * You can find the original source code at: * https://github.com/imneme/pcg-c * * ----------------------------------------------------------------------------- * * This code is under the following license: * * Copyright (c) 2014-2017 Melissa O'Neill and PCG Project contributors * Copyright (c) 2018-2021 Gavin D. Howard and contributors. * * Permission is hereby granted, free of charge, to any person obtaining a copy * of this software and associated documentation files (the "Software"), to deal * in the Software without restriction, including without limitation the rights * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell * copies of the Software, and to permit persons to whom the Software is * furnished to do so, subject to the following conditions: * * The above copyright notice and this permission notice shall be included in * all copies or substantial portions of the Software. * * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE * SOFTWARE. * * ***************************************************************************** * * Code for the RNG. * */ #include #include #include #include #include #ifndef _WIN32 #include #else // _WIN32 #include #include #endif // _WIN32 #include #include #include #if BC_ENABLE_EXTRA_MATH #if !BC_RAND_BUILTIN /** * Adds two 64-bit values and preserves the overflow. * @param a The first operand. * @param b The second operand. * @return The sum, including overflow. */ static BcRandState bc_rand_addition(uint_fast64_t a, uint_fast64_t b) { BcRandState res; res.lo = a + b; res.hi = (res.lo < a); return res; } /** * Adds two 128-bit values and discards the overflow. * @param a The first operand. * @param b The second operand. * @return The sum, without overflow. */ static BcRandState bc_rand_addition2(BcRandState a, BcRandState b) { BcRandState temp, res; res = bc_rand_addition(a.lo, b.lo); temp = bc_rand_addition(a.hi, b.hi); res.hi += temp.lo; return res; } /** * Multiplies two 64-bit values and preserves the overflow. * @param a The first operand. * @param b The second operand. * @return The product, including overflow. */ static BcRandState bc_rand_multiply(uint_fast64_t a, uint_fast64_t b) { uint_fast64_t al, ah, bl, bh, c0, c1, c2, c3; BcRandState carry, res; al = BC_RAND_TRUNC32(a); ah = BC_RAND_CHOP32(a); bl = BC_RAND_TRUNC32(b); bh = BC_RAND_CHOP32(b); c0 = al * bl; c1 = al * bh; c2 = ah * bl; c3 = ah * bh; carry = bc_rand_addition(c1, c2); res = bc_rand_addition(c0, (BC_RAND_TRUNC32(carry.lo)) << 32); res.hi += BC_RAND_CHOP32(carry.lo) + c3 + (carry.hi << 32); return res; } /** * Multiplies two 128-bit values and discards the overflow. * @param a The first operand. * @param b The second operand. * @return The product, without overflow. */ static BcRandState bc_rand_multiply2(BcRandState a, BcRandState b) { BcRandState c0, c1, c2, carry; c0 = bc_rand_multiply(a.lo, b.lo); c1 = bc_rand_multiply(a.lo, b.hi); c2 = bc_rand_multiply(a.hi, b.lo); carry = bc_rand_addition2(c1, c2); carry.hi = carry.lo; carry.lo = 0; return bc_rand_addition2(c0, carry); } #endif // BC_RAND_BUILTIN /** * Marks a PRNG as modified. This is important for properly maintaining the * stack of PRNG's. * @param r The PRNG to mark as modified. */ static void bc_rand_setModified(BcRNGData *r) { #if BC_RAND_BUILTIN r->inc |= (BcRandState) 1UL; #else // BC_RAND_BUILTIN r->inc.lo |= (uint_fast64_t) 1UL; #endif // BC_RAND_BUILTIN } /** * Marks a PRNG as not modified. This is important for properly maintaining the * stack of PRNG's. * @param r The PRNG to mark as not modified. */ static void bc_rand_clearModified(BcRNGData *r) { #if BC_RAND_BUILTIN r->inc &= ~((BcRandState) 1UL); #else // BC_RAND_BUILTIN r->inc.lo &= ~(1UL); #endif // BC_RAND_BUILTIN } /** * Copies a PRNG to another and marks the copy as modified if it already was or * marks it modified if it already was. * @param d The destination PRNG. * @param s The source PRNG. */ static void bc_rand_copy(BcRNGData *d, BcRNGData *s) { bool unmod = BC_RAND_NOTMODIFIED(d); memcpy(d, s, sizeof(BcRNGData)); if (!unmod) bc_rand_setModified(d); else if (!BC_RAND_NOTMODIFIED(s)) bc_rand_clearModified(d); } #ifndef _WIN32 /** * Reads random data from a file. * @param ptr A pointer to the file, as a void pointer. * @return The random data as an unsigned long. */ static ulong bc_rand_frand(void* ptr) { ulong buf[1]; int fd; ssize_t nread; assert(ptr != NULL); fd = *((int*)ptr); nread = read(fd, buf, sizeof(ulong)); if (BC_ERR(nread != sizeof(ulong))) bc_vm_fatalError(BC_ERR_FATAL_IO_ERR); return *((ulong*)buf); } #else // _WIN32 /** * Reads random data from BCryptGenRandom(). * @param ptr An unused parameter. * @return The random data as an unsigned long. */ static ulong bc_rand_winrand(void *ptr) { ulong buf[1]; NTSTATUS s; BC_UNUSED(ptr); buf[0] = 0; s = BCryptGenRandom(NULL, (char*) buf, sizeof(ulong), BCRYPT_USE_SYSTEM_PREFERRED_RNG); if (BC_ERR(!BCRYPT_SUCCESS(s))) buf[0] = 0; return buf[0]; } #endif // _WIN32 /** * Reads random data from rand(), byte-by-byte because rand() is only guaranteed * to return 15 bits of random data. This is the final fallback and is not * preferred as it is possible to access cryptographically-secure PRNG's on most * systems. * @param ptr An unused parameter. * @return The random data as an unsigned long. */ static ulong bc_rand_rand(void *ptr) { size_t i; ulong res = 0; BC_UNUSED(ptr); // Fill up the unsigned long byte-by-byte. for (i = 0; i < sizeof(ulong); ++i) res |= ((ulong) (rand() & BC_RAND_SRAND_BITS)) << (i * CHAR_BIT); return res; } /** * Returns the actual increment of the PRNG, including the required last odd * bit. * @param r The PRNG. * @return The increment of the PRNG, including the last odd bit. */ static BcRandState bc_rand_inc(BcRNGData *r) { BcRandState inc; #if BC_RAND_BUILTIN inc = r->inc | 1; #else // BC_RAND_BUILTIN inc.lo = r->inc.lo | 1; inc.hi = r->inc.hi; #endif // BC_RAND_BUILTIN return inc; } /** * Sets up the increment for the PRNG. * @param r The PRNG whose increment will be set up. */ static void bc_rand_setupInc(BcRNGData *r) { #if BC_RAND_BUILTIN r->inc <<= 1UL; #else // BC_RAND_BUILTIN r->inc.hi <<= 1UL; r->inc.hi |= (r->inc.lo & (1UL << (BC_LONG_BIT - 1))) >> (BC_LONG_BIT - 1); r->inc.lo <<= 1UL; #endif // BC_RAND_BUILTIN } /** * Seeds the state of a PRNG. * @param state The return parameter; the state to seed. * @param val1 The lower half of the state. * @param val2 The upper half of the state. */ static void bc_rand_seedState(BcRandState *state, ulong val1, ulong val2) { #if BC_RAND_BUILTIN *state = ((BcRandState) val1) | ((BcRandState) val2) << (BC_LONG_BIT); #else // BC_RAND_BUILTIN state->lo = val1; state->hi = val2; #endif // BC_RAND_BUILTIN } /** * Seeds a PRNG. * @param r The return parameter; the PRNG to seed. * @param state1 The lower half of the state. * @param state2 The upper half of the state. * @param inc1 The lower half of the increment. * @param inc2 The upper half of the increment. */ static void bc_rand_seedRNG(BcRNGData *r, ulong state1, ulong state2, ulong inc1, ulong inc2) { bc_rand_seedState(&r->state, state1, state2); bc_rand_seedState(&r->inc, inc1, inc2); bc_rand_setupInc(r); } /** * Fills a PRNG with random data to seed it. * @param r The PRNG. * @param fulong The function to fill an unsigned long. * @param ptr The parameter to pass to @a fulong. */ static void bc_rand_fill(BcRNGData *r, BcRandUlong fulong, void *ptr) { ulong state1, state2, inc1, inc2; state1 = fulong(ptr); state2 = fulong(ptr); inc1 = fulong(ptr); inc2 = fulong(ptr); bc_rand_seedRNG(r, state1, state2, inc1, inc2); } /** * Executes the "step" portion of a PCG udpate. * @param r The PRNG. */ static void bc_rand_step(BcRNGData *r) { BcRandState temp = bc_rand_mul2(r->state, bc_rand_multiplier); r->state = bc_rand_add2(temp, bc_rand_inc(r)); } /** * Returns the new output of PCG. * @param r The PRNG. * @return The new output from the PRNG. */ static BcRand bc_rand_output(BcRNGData *r) { return BC_RAND_ROT(BC_RAND_FOLD(r->state), BC_RAND_ROTAMT(r->state)); } /** * Seeds every PRNG on the PRNG stack between the top and @a idx that has not * been seeded. * @param r The PRNG stack. * @param rng The PRNG on the top of the stack. Must have been seeded. */ static void bc_rand_seedZeroes(BcRNG *r, BcRNGData *rng, size_t idx) { BcRNGData *rng2; // Just return if there are none to do. if (r->v.len <= idx) return; // Get the first PRNG that might need to be seeded. rng2 = bc_vec_item_rev(&r->v, idx); // Does it need seeding? Then it, and maybe more, do. if (BC_RAND_ZERO(rng2)) { size_t i; // Seed the ones that need seeding. for (i = 1; i < r->v.len; ++i) bc_rand_copy(bc_vec_item_rev(&r->v, i), rng); } } void bc_rand_srand(BcRNGData *rng) { int fd = 0; BC_SIG_LOCK; #ifndef _WIN32 // Try /dev/urandom first. fd = open("/dev/urandom", O_RDONLY); if (BC_NO_ERR(fd >= 0)) { bc_rand_fill(rng, bc_rand_frand, &fd); close(fd); } else { // Try /dev/random second. fd = open("/dev/random", O_RDONLY); if (BC_NO_ERR(fd >= 0)) { bc_rand_fill(rng, bc_rand_frand, &fd); close(fd); } } #else // _WIN32 // Try BCryptGenRandom first. bc_rand_fill(rng, bc_rand_winrand, NULL); #endif // _WIN32 // Fallback to rand() until the thing is seeded. while (BC_ERR(BC_RAND_ZERO(rng))) bc_rand_fill(rng, bc_rand_rand, NULL); BC_SIG_UNLOCK; } /** * Propagates a change to the PRNG to all PRNG's in the stack that should have * it. The ones that should have it are laid out in the manpages. * @param r The PRNG stack. * @param rng The PRNG that will be used to seed the others. */ static void bc_rand_propagate(BcRNG *r, BcRNGData *rng) { // Just return if there are none to do. if (r->v.len <= 1) return; // If the PRNG has not been modified... if (BC_RAND_NOTMODIFIED(rng)) { size_t i; bool go = true; // Find the first PRNG that is modified and seed the others. for (i = 1; go && i < r->v.len; ++i) { BcRNGData *rng2 = bc_vec_item_rev(&r->v, i); go = BC_RAND_NOTMODIFIED(rng2); bc_rand_copy(rng2, rng); } // Seed everything else. bc_rand_seedZeroes(r, rng, i); } // Seed everything. else bc_rand_seedZeroes(r, rng, 1); } BcRand bc_rand_int(BcRNG *r) { // Get the actual PRNG. BcRNGData *rng = bc_vec_top(&r->v); + BcRand res; // Make sure the PRNG is seeded. if (BC_ERR(BC_RAND_ZERO(rng))) bc_rand_srand(rng); - // This is the important part of the PRNG. This is the stuff from PCG, - // including the return statement. + BC_SIG_LOCK; + + // This is the important part of the PRNG. This is the stuff from PCG. bc_rand_step(rng); bc_rand_propagate(r, rng); + res = bc_rand_output(rng); - return bc_rand_output(rng); + BC_SIG_UNLOCK; + + return res; } BcRand bc_rand_bounded(BcRNG *r, BcRand bound) { // Calculate the threshold below which we have to try again. BcRand rand, threshold = (0 - bound) % bound; do { rand = bc_rand_int(r); } while (rand < threshold); return rand % bound; } void bc_rand_seed(BcRNG *r, ulong state1, ulong state2, ulong inc1, ulong inc2) { // Get the actual PRNG. BcRNGData *rng = bc_vec_top(&r->v); // Seed and set up the PRNG's increment. bc_rand_seedState(&rng->inc, inc1, inc2); bc_rand_setupInc(rng); bc_rand_setModified(rng); // If the state is 0, use the increment as the state. Otherwise, seed it // with the state. if (!state1 && !state2) { memcpy(&rng->state, &rng->inc, sizeof(BcRandState)); bc_rand_step(rng); } else bc_rand_seedState(&rng->state, state1, state2); // Propagate the change to PRNG's that need it. bc_rand_propagate(r, rng); } /** * Returns the increment in the PRNG *without* the odd bit and also with being * shifted one bit down. * @param r The PRNG. * @return The increment without the odd bit and with being shifted one bit * down. */ static BcRandState bc_rand_getInc(BcRNGData *r) { BcRandState res; #if BC_RAND_BUILTIN res = r->inc >> 1; #else // BC_RAND_BUILTIN res = r->inc; res.lo >>= 1; res.lo |= (res.hi & 1) << (BC_LONG_BIT - 1); res.hi >>= 1; #endif // BC_RAND_BUILTIN return res; } void bc_rand_getRands(BcRNG *r, BcRand *s1, BcRand *s2, BcRand *i1, BcRand *i2) { BcRandState inc; BcRNGData *rng = bc_vec_top(&r->v); if (BC_ERR(BC_RAND_ZERO(rng))) bc_rand_srand(rng); // Get the increment. inc = bc_rand_getInc(rng); // Chop the state. *s1 = BC_RAND_TRUNC(rng->state); *s2 = BC_RAND_CHOP(rng->state); // Chop the increment. *i1 = BC_RAND_TRUNC(inc); *i2 = BC_RAND_CHOP(inc); } void bc_rand_push(BcRNG *r) { BcRNGData *rng = bc_vec_pushEmpty(&r->v); // Make sure the PRNG is properly zeroed because that marks it as needing to // be seeded. memset(rng, 0, sizeof(BcRNGData)); // If there is another item, copy it too. if (r->v.len > 1) bc_rand_copy(rng, bc_vec_item_rev(&r->v, 1)); } void bc_rand_pop(BcRNG *r, bool reset) { bc_vec_npop(&r->v, reset ? r->v.len - 1 : 1); } void bc_rand_init(BcRNG *r) { BC_SIG_ASSERT_LOCKED; bc_vec_init(&r->v, sizeof(BcRNGData), BC_DTOR_NONE); bc_rand_push(r); } #if BC_RAND_USE_FREE void bc_rand_free(BcRNG *r) { BC_SIG_ASSERT_LOCKED; bc_vec_free(&r->v); } #endif // BC_RAND_USE_FREE #endif // BC_ENABLE_EXTRA_MATH diff --git a/contrib/bc/src/read.c b/contrib/bc/src/read.c index 84621ad3acac..b9cd4db7bb49 100644 --- a/contrib/bc/src/read.c +++ b/contrib/bc/src/read.c @@ -1,299 +1,303 @@ /* * ***************************************************************************** * * SPDX-License-Identifier: BSD-2-Clause * * Copyright (c) 2018-2021 Gavin D. Howard and contributors. * * Redistribution and use in source and binary forms, with or without * modification, are permitted provided that the following conditions are met: * * * Redistributions of source code must retain the above copyright notice, this * list of conditions and the following disclaimer. * * * Redistributions in binary form must reproduce the above copyright notice, * this list of conditions and the following disclaimer in the documentation * and/or other materials provided with the distribution. * * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE * POSSIBILITY OF SUCH DAMAGE. * * ***************************************************************************** * * Code to handle special I/O for bc. * */ #include #include #include #include #include #include #include #include #ifndef _WIN32 #include #endif // _WIN32 #include #include #include #include /** * A portability file open function. * @param path The path to the file to open. * @param mode The mode to open in. */ static int bc_read_open(const char* path, int mode) { int fd; #ifndef _WIN32 fd = open(path, mode); #else // _WIN32 fd = -1; open(&fd, path, mode); #endif return fd; } /** * Returns true if the buffer data is non-text. * @param buf The buffer to test. * @param size The size of the buffer. */ static bool bc_read_binary(const char *buf, size_t size) { size_t i; for (i = 0; i < size; ++i) { if (BC_ERR(BC_READ_BIN_CHAR(buf[i]))) return true; } return false; } bool bc_read_buf(BcVec *vec, char *buf, size_t *buf_len) { char *nl; // If nothing there, return. if (!*buf_len) return false; // Find the newline. nl = strchr(buf, '\n'); // If a newline exists... if (nl != NULL) { // Get the size of the data up to, and including, the newline. size_t nllen = (size_t) ((nl + 1) - buf); nllen = *buf_len >= nllen ? nllen : *buf_len; // Move data into the vector, and move the rest of the data in the // buffer up. bc_vec_npush(vec, nllen, buf); *buf_len -= nllen; memmove(buf, nl + 1, *buf_len + 1); return true; } // Just put the data into the vector. bc_vec_npush(vec, *buf_len, buf); *buf_len = 0; return false; } BcStatus bc_read_chars(BcVec *vec, const char *prompt) { bool done = false; assert(vec != NULL && vec->size == sizeof(char)); BC_SIG_ASSERT_NOT_LOCKED; // Clear the vector. bc_vec_popAll(vec); // Handle the prompt, if desired. if (BC_PROMPT) { bc_file_puts(&vm.fout, bc_flush_none, prompt); bc_file_flush(&vm.fout, bc_flush_none); } // Try reading from the buffer, and if successful, just return. if (bc_read_buf(vec, vm.buf, &vm.buf_len)) { bc_vec_pushByte(vec, '\0'); return BC_STATUS_SUCCESS; } // Loop until we have something. while (!done) { ssize_t r; BC_SIG_LOCK; // Read data from stdin. r = read(STDIN_FILENO, vm.buf + vm.buf_len, BC_VM_STDIN_BUF_SIZE - vm.buf_len); // If there was an error... if (BC_UNLIKELY(r < 0)) { // If interupted... if (errno == EINTR) { // Jump out if we are supposed to quit, which certain signals // will require. if (vm.status == (sig_atomic_t) BC_STATUS_QUIT) BC_JMP; assert(vm.sig); // Clear the signal and status. vm.sig = 0; vm.status = (sig_atomic_t) BC_STATUS_SUCCESS; // Print the ready message and prompt again. bc_file_puts(&vm.fout, bc_flush_none, bc_program_ready_msg); if (BC_PROMPT) bc_file_puts(&vm.fout, bc_flush_none, prompt); bc_file_flush(&vm.fout, bc_flush_none); BC_SIG_UNLOCK; continue; } BC_SIG_UNLOCK; // If we get here, it's bad. Barf. bc_vm_fatalError(BC_ERR_FATAL_IO_ERR); } BC_SIG_UNLOCK; // If we read nothing, make sure to terminate the string and return EOF. if (r == 0) { bc_vec_pushByte(vec, '\0'); return BC_STATUS_EOF; } + BC_SIG_LOCK; + // Add to the buffer. vm.buf_len += (size_t) r; vm.buf[vm.buf_len] = '\0'; // Read from the buffer. done = bc_read_buf(vec, vm.buf, &vm.buf_len); + + BC_SIG_UNLOCK; } // Terminate the string. bc_vec_pushByte(vec, '\0'); return BC_STATUS_SUCCESS; } BcStatus bc_read_line(BcVec *vec, const char *prompt) { BcStatus s; #if BC_ENABLE_HISTORY // Get a line from either history or manual reading. if (BC_TTY && !vm.history.badTerm) s = bc_history_line(&vm.history, vec, prompt); else s = bc_read_chars(vec, prompt); #else // BC_ENABLE_HISTORY s = bc_read_chars(vec, prompt); #endif // BC_ENABLE_HISTORY if (BC_ERR(bc_read_binary(vec->v, vec->len - 1))) bc_verr(BC_ERR_FATAL_BIN_FILE, bc_program_stdin_name); return s; } char* bc_read_file(const char *path) { BcErr e = BC_ERR_FATAL_IO_ERR; size_t size, to_read; struct stat pstat; int fd; char* buf; char* buf2; BC_SIG_ASSERT_LOCKED; assert(path != NULL); #ifndef NDEBUG // Need this to quiet MSan. memset(&pstat, 0, sizeof(struct stat)); #endif // NDEBUG fd = bc_read_open(path, O_RDONLY); // If we can't read a file, we just barf. if (BC_ERR(fd < 0)) bc_verr(BC_ERR_FATAL_FILE_ERR, path); // The reason we call fstat is to eliminate TOCTOU race conditions. This // way, we have an open file, so it's not going anywhere. if (BC_ERR(fstat(fd, &pstat) == -1)) goto malloc_err; // Make sure it's not a directory. if (BC_ERR(S_ISDIR(pstat.st_mode))) { e = BC_ERR_FATAL_PATH_DIR; goto malloc_err; } // Get the size of the file and allocate that much. size = (size_t) pstat.st_size; buf = bc_vm_malloc(size + 1); buf2 = buf; to_read = size; do { // Read the file. We just bail if a signal interrupts. This is so that // users can interrupt the reading of big files if they want. ssize_t r = read(fd, buf2, to_read); if (BC_ERR(r < 0)) goto read_err; to_read -= (size_t) r; buf2 += (size_t) r; } while (to_read); // Got to have a nul byte. buf[size] = '\0'; if (BC_ERR(bc_read_binary(buf, size))) { e = BC_ERR_FATAL_BIN_FILE; goto read_err; } close(fd); return buf; read_err: free(buf); malloc_err: close(fd); bc_verr(e, path); return NULL; } diff --git a/contrib/bc/src/vm.c b/contrib/bc/src/vm.c index 853dff0820dd..ef2257644f52 100644 --- a/contrib/bc/src/vm.c +++ b/contrib/bc/src/vm.c @@ -1,1437 +1,1461 @@ /* * ***************************************************************************** * * SPDX-License-Identifier: BSD-2-Clause * * Copyright (c) 2018-2021 Gavin D. Howard and contributors. * * Redistribution and use in source and binary forms, with or without * modification, are permitted provided that the following conditions are met: * * * Redistributions of source code must retain the above copyright notice, this * list of conditions and the following disclaimer. * * * Redistributions in binary form must reproduce the above copyright notice, * this list of conditions and the following disclaimer in the documentation * and/or other materials provided with the distribution. * * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE * POSSIBILITY OF SUCH DAMAGE. * * ***************************************************************************** * * Code common to all of bc and dc. * */ #include #include #include #include #include #include #include #ifndef _WIN32 #include #include #include #else // _WIN32 #define WIN32_LEAN_AND_MEAN #include #include #endif // _WIN32 #include #include #include #include #include #include // The actual globals. static BcDig* temps_buf[BC_VM_MAX_TEMPS]; char output_bufs[BC_VM_BUF_SIZE]; BcVm vm; #if BC_DEBUG_CODE BC_NORETURN void bc_vm_jmp(const char* f) { #else // BC_DEBUG_CODE BC_NORETURN void bc_vm_jmp(void) { #endif assert(BC_SIG_EXC); BC_SIG_MAYLOCK; #if BC_DEBUG_CODE bc_file_puts(&vm.ferr, bc_flush_none, "Longjmp: "); bc_file_puts(&vm.ferr, bc_flush_none, f); bc_file_putchar(&vm.ferr, bc_flush_none, '\n'); bc_file_flush(&vm.ferr, bc_flush_none); #endif // BC_DEBUG_CODE #ifndef NDEBUG assert(vm.jmp_bufs.len - (size_t) vm.sig_pop); #endif // NDEBUG if (vm.jmp_bufs.len == 0) abort(); if (vm.sig_pop) bc_vec_pop(&vm.jmp_bufs); else vm.sig_pop = 1; siglongjmp(*((sigjmp_buf*) bc_vec_top(&vm.jmp_bufs)), 1); } #if !BC_ENABLE_LIBRARY /** * Handles signals. This is the signal handler. * @param sig The signal to handle. */ static void bc_vm_sig(int sig) { // There is already a signal in flight. if (vm.status == (sig_atomic_t) BC_STATUS_QUIT || vm.sig) { if (!BC_I || sig != SIGINT) vm.status = BC_STATUS_QUIT; return; } // Only reset under these conditions; otherwise, quit. if (sig == SIGINT && BC_SIGINT && BC_I) { int err = errno; // Write the message. if (write(STDOUT_FILENO, vm.sigmsg, vm.siglen) != (ssize_t) vm.siglen) vm.status = BC_STATUS_ERROR_FATAL; else vm.sig = 1; errno = err; } else vm.status = BC_STATUS_QUIT; assert(vm.jmp_bufs.len); // Only jump if signals are not locked. The jump will happen by whoever // unlocks signals. if (!vm.sig_lock) BC_JMP; } /** * Sets up signal handling. */ static void bc_vm_sigaction(void) { #ifndef _WIN32 struct sigaction sa; sigemptyset(&sa.sa_mask); sa.sa_handler = bc_vm_sig; sa.sa_flags = SA_NODEFER; sigaction(SIGTERM, &sa, NULL); sigaction(SIGQUIT, &sa, NULL); sigaction(SIGINT, &sa, NULL); #if BC_ENABLE_HISTORY if (BC_TTY) sigaction(SIGHUP, &sa, NULL); #endif // BC_ENABLE_HISTORY #else // _WIN32 signal(SIGTERM, bc_vm_sig); signal(SIGINT, bc_vm_sig); #endif // _WIN32 } void bc_vm_info(const char* const help) { BC_SIG_ASSERT_LOCKED; // Print the banner. bc_file_puts(&vm.fout, bc_flush_none, vm.name); bc_file_putchar(&vm.fout, bc_flush_none, ' '); bc_file_puts(&vm.fout, bc_flush_none, BC_VERSION); bc_file_putchar(&vm.fout, bc_flush_none, '\n'); bc_file_puts(&vm.fout, bc_flush_none, bc_copyright); // Print the help. if (help) { bc_file_putchar(&vm.fout, bc_flush_none, '\n'); #if BC_ENABLED if (BC_IS_BC) { const char* const banner = BC_DEFAULT_BANNER ? "to" : "to not"; const char* const sigint = BC_DEFAULT_SIGINT_RESET ? "to reset" : "to exit"; const char* const tty = BC_DEFAULT_TTY_MODE ? "enabled" : "disabled"; const char* const prompt = BC_DEFAULT_PROMPT ? "enabled" : "disabled"; + const char* const expr = BC_DEFAULT_EXPR_EXIT ? "to exit" : + "to not exit"; bc_file_printf(&vm.fout, help, vm.name, vm.name, BC_VERSION, - BC_BUILD_TYPE, banner, sigint, tty, prompt); + BC_BUILD_TYPE, banner, sigint, tty, prompt, expr); } #endif // BC_ENABLED #if DC_ENABLED if (BC_IS_DC) { const char* const sigint = DC_DEFAULT_SIGINT_RESET ? "to reset" : "to exit"; const char* const tty = DC_DEFAULT_TTY_MODE ? "enabled" : "disabled"; const char* const prompt = DC_DEFAULT_PROMPT ? "enabled" : "disabled"; + const char* const expr = DC_DEFAULT_EXPR_EXIT ? "to exit" : + "to not exit"; bc_file_printf(&vm.fout, help, vm.name, vm.name, BC_VERSION, - BC_BUILD_TYPE, sigint, tty, prompt); + BC_BUILD_TYPE, sigint, tty, prompt, expr); } #endif // DC_ENABLED } // Flush. bc_file_flush(&vm.fout, bc_flush_none); } #endif // !BC_ENABLE_LIBRARY #if !BC_ENABLE_LIBRARY && !BC_ENABLE_MEMCHECK BC_NORETURN #endif // !BC_ENABLE_LIBRARY && !BC_ENABLE_MEMCHECK void bc_vm_fatalError(BcErr e) { bc_err(e); #if !BC_ENABLE_LIBRARY && !BC_ENABLE_MEMCHECK BC_UNREACHABLE abort(); #endif // !BC_ENABLE_LIBRARY && !BC_ENABLE_MEMCHECK } #if BC_ENABLE_LIBRARY void bc_vm_handleError(BcErr e) { assert(e < BC_ERR_NELEMS); assert(!vm.sig_pop); BC_SIG_LOCK; // If we have a normal error... if (e <= BC_ERR_MATH_DIVIDE_BY_ZERO) { // Set the error. vm.err = (BclError) (e - BC_ERR_MATH_NEGATIVE + BCL_ERROR_MATH_NEGATIVE); } // Abort if we should. else if (vm.abrt) abort(); else if (e == BC_ERR_FATAL_ALLOC_ERR) vm.err = BCL_ERROR_FATAL_ALLOC_ERR; else vm.err = BCL_ERROR_FATAL_UNKNOWN_ERR; BC_JMP; } #else // BC_ENABLE_LIBRARY void bc_vm_handleError(BcErr e, size_t line, ...) { BcStatus s; va_list args; uchar id = bc_err_ids[e]; const char* err_type = vm.err_ids[id]; sig_atomic_t lock; assert(e < BC_ERR_NELEMS); assert(!vm.sig_pop); #if BC_ENABLED // Figure out if the POSIX error should be an error, a warning, or nothing. if (!BC_S && e >= BC_ERR_POSIX_START) { if (BC_W) { // Make sure to not return an error. id = UCHAR_MAX; err_type = vm.err_ids[BC_ERR_IDX_WARN]; } else return; } #endif // BC_ENABLED BC_SIG_TRYLOCK(lock); // Make sure all of stdout is written first. s = bc_file_flushErr(&vm.fout, bc_flush_err); // Just jump out if the flush failed; there's nothing we can do. if (BC_ERR(s == BC_STATUS_ERROR_FATAL)) { vm.status = (sig_atomic_t) s; BC_JMP; } // Print the error message. va_start(args, line); bc_file_putchar(&vm.ferr, bc_flush_none, '\n'); bc_file_puts(&vm.ferr, bc_flush_none, err_type); bc_file_putchar(&vm.ferr, bc_flush_none, ' '); bc_file_vprintf(&vm.ferr, vm.err_msgs[e], args); va_end(args); // Print the extra information if we have it. if (BC_NO_ERR(vm.file != NULL)) { // This is the condition for parsing vs runtime. // If line is not 0, it is parsing. if (line) { bc_file_puts(&vm.ferr, bc_flush_none, "\n "); bc_file_puts(&vm.ferr, bc_flush_none, vm.file); bc_file_printf(&vm.ferr, bc_err_line, line); } else { BcInstPtr *ip = bc_vec_item_rev(&vm.prog.stack, 0); BcFunc *f = bc_vec_item(&vm.prog.fns, ip->func); bc_file_puts(&vm.ferr, bc_flush_none, "\n "); bc_file_puts(&vm.ferr, bc_flush_none, vm.func_header); bc_file_putchar(&vm.ferr, bc_flush_none, ' '); bc_file_puts(&vm.ferr, bc_flush_none, f->name); #if BC_ENABLED if (BC_IS_BC && ip->func != BC_PROG_MAIN && ip->func != BC_PROG_READ) { bc_file_puts(&vm.ferr, bc_flush_none, "()"); } #endif // BC_ENABLED } } bc_file_puts(&vm.ferr, bc_flush_none, "\n\n"); s = bc_file_flushErr(&vm.ferr, bc_flush_err); #if !BC_ENABLE_MEMCHECK // Because this function is called by a BC_NORETURN function when fatal // errors happen, we need to make sure to exit on fatal errors. This will // be faster anyway. This function *cannot jump when a fatal error occurs!* if (BC_ERR(id == BC_ERR_IDX_FATAL || s == BC_STATUS_ERROR_FATAL)) exit(bc_vm_atexit((int) BC_STATUS_ERROR_FATAL)); #else // !BC_ENABLE_MEMCHECK if (BC_ERR(s == BC_STATUS_ERROR_FATAL)) vm.status = (sig_atomic_t) s; else #endif // !BC_ENABLE_MEMCHECK { vm.status = (sig_atomic_t) (uchar) (id + 1); } // Only jump if there is an error. if (BC_ERR(vm.status)) BC_JMP; BC_SIG_TRYUNLOCK(lock); } char* bc_vm_getenv(const char* var) { char* ret; #ifndef _WIN32 ret = getenv(var); #else // _WIN32 _dupenv_s(&ret, NULL, var); #endif // _WIN32 return ret; } void bc_vm_getenvFree(char* val) { BC_UNUSED(val); #ifdef _WIN32 free(val); #endif // _WIN32 } /** * Sets a flag from an environment variable and the default. * @param var The environment variable. * @param def The default. * @param flag The flag to set. */ static void bc_vm_setenvFlag(const char* const var, int def, uint16_t flag) { // Get the value. char* val = bc_vm_getenv(var); // If there is no value... if (val == NULL) { // Set the default. if (def) vm.flags |= flag; else vm.flags &= ~(flag); } // Parse the value. else if (strtoul(val, NULL, 0)) vm.flags |= flag; else vm.flags &= ~(flag); bc_vm_getenvFree(val); } /** * Parses the arguments in {B,D]C_ENV_ARGS. * @param env_args_name The environment variable to use. */ static void bc_vm_envArgs(const char* const env_args_name) { char *env_args = bc_vm_getenv(env_args_name), *buf, *start; char instr = '\0'; BC_SIG_ASSERT_LOCKED; if (env_args == NULL) return; // Windows already allocates, so we don't need to. #ifndef _WIN32 start = buf = vm.env_args_buffer = bc_vm_strdup(env_args); #else // _WIN32 start = buf = vm.env_args_buffer = env_args; #endif // _WIN32 assert(buf != NULL); // Create two buffers for parsing. These need to stay throughout the entire // execution of bc, unfortunately, because of filenames that might be in // there. bc_vec_init(&vm.env_args, sizeof(char*), BC_DTOR_NONE); bc_vec_push(&vm.env_args, &env_args_name); // While we haven't reached the end of the args... while (*buf) { // If we don't have whitespace... if (!isspace(*buf)) { // If we have the start of a string... if (*buf == '"' || *buf == '\'') { // Set stuff appropriately. instr = *buf; buf += 1; // Check for the empty string. if (*buf == instr) { instr = '\0'; buf += 1; continue; } } // Push the pointer to the args buffer. bc_vec_push(&vm.env_args, &buf); // Parse the string. while (*buf && ((!instr && !isspace(*buf)) || (instr && *buf != instr))) { buf += 1; } // If we did find the end of the string... if (*buf) { if (instr) instr = '\0'; // Reset stuff. *buf = '\0'; buf += 1; start = buf; } else if (instr) bc_error(BC_ERR_FATAL_OPTION, 0, start); } // If we have whitespace, eat it. else buf += 1; } // Make sure to push a NULL pointer at the end. buf = NULL; bc_vec_push(&vm.env_args, &buf); // Parse the arguments. bc_args((int) vm.env_args.len - 1, bc_vec_item(&vm.env_args, 0), false); } /** * Gets the {B,D}C_LINE_LENGTH. * @param var The environment variable to pull it from. * @return The line length. */ static size_t bc_vm_envLen(const char *var) { char *lenv = bc_vm_getenv(var); size_t i, len = BC_NUM_PRINT_WIDTH; int num; // Return the default with none. if (lenv == NULL) return len; len = strlen(lenv); // Figure out if it's a number. for (num = 1, i = 0; num && i < len; ++i) num = isdigit(lenv[i]); // If it is a number... if (num) { // Parse it and clamp it if needed. len = (size_t) atoi(lenv) - 1; if (len == 1 || len >= UINT16_MAX) len = BC_NUM_PRINT_WIDTH; } // Set the default. else len = BC_NUM_PRINT_WIDTH; bc_vm_getenvFree(lenv); return len; } #endif // BC_ENABLE_LIBRARY void bc_vm_shutdown(void) { BC_SIG_ASSERT_LOCKED; #if BC_ENABLE_NLS if (vm.catalog != BC_VM_INVALID_CATALOG) catclose(vm.catalog); #endif // BC_ENABLE_NLS #if BC_ENABLE_HISTORY // This must always run to ensure that the terminal is back to normal, i.e., // has raw mode disabled. if (BC_TTY) bc_history_free(&vm.history); #endif // BC_ENABLE_HISTORY #ifndef NDEBUG #if !BC_ENABLE_LIBRARY bc_vec_free(&vm.env_args); free(vm.env_args_buffer); bc_vec_free(&vm.files); bc_vec_free(&vm.exprs); if (BC_PARSE_IS_INITED(&vm.read_prs, &vm.prog)) { bc_vec_free(&vm.read_buf); bc_parse_free(&vm.read_prs); } bc_parse_free(&vm.prs); bc_program_free(&vm.prog); bc_slabvec_free(&vm.other_slabs); bc_slabvec_free(&vm.main_slabs); bc_slabvec_free(&vm.main_const_slab); #endif // !BC_ENABLE_LIBRARY bc_vm_freeTemps(); #endif // NDEBUG #if !BC_ENABLE_LIBRARY // We always want to flush. bc_file_free(&vm.fout); bc_file_free(&vm.ferr); #endif // !BC_ENABLE_LIBRARY } void bc_vm_addTemp(BcDig *num) { + BC_SIG_ASSERT_LOCKED; + // If we don't have room, just free. if (vm.temps_len == BC_VM_MAX_TEMPS) free(num); else { // Add to the buffer and length. temps_buf[vm.temps_len] = num; vm.temps_len += 1; } } BcDig* bc_vm_takeTemp(void) { + + BC_SIG_ASSERT_LOCKED; + if (!vm.temps_len) return NULL; + vm.temps_len -= 1; + return temps_buf[vm.temps_len]; } void bc_vm_freeTemps(void) { size_t i; BC_SIG_ASSERT_LOCKED; if (!vm.temps_len) return; // Free them all... for (i = 0; i < vm.temps_len; ++i) free(temps_buf[i]); vm.temps_len = 0; } inline size_t bc_vm_arraySize(size_t n, size_t size) { size_t res = n * size; if (BC_ERR(BC_VM_MUL_OVERFLOW(n, size, res))) bc_vm_fatalError(BC_ERR_FATAL_ALLOC_ERR); return res; } inline size_t bc_vm_growSize(size_t a, size_t b) { size_t res = a + b; if (BC_ERR(res >= SIZE_MAX || res < a)) bc_vm_fatalError(BC_ERR_FATAL_ALLOC_ERR); return res; } void* bc_vm_malloc(size_t n) { void* ptr; BC_SIG_ASSERT_LOCKED; ptr = malloc(n); if (BC_ERR(ptr == NULL)) { bc_vm_freeTemps(); ptr = malloc(n); if (BC_ERR(ptr == NULL)) bc_vm_fatalError(BC_ERR_FATAL_ALLOC_ERR); } return ptr; } void* bc_vm_realloc(void *ptr, size_t n) { void* temp; BC_SIG_ASSERT_LOCKED; temp = realloc(ptr, n); if (BC_ERR(temp == NULL)) { bc_vm_freeTemps(); temp = realloc(ptr, n); if (BC_ERR(temp == NULL)) bc_vm_fatalError(BC_ERR_FATAL_ALLOC_ERR); } return temp; } char* bc_vm_strdup(const char *str) { char *s; BC_SIG_ASSERT_LOCKED; s = strdup(str); if (BC_ERR(s == NULL)) { bc_vm_freeTemps(); s = strdup(str); if (BC_ERR(s == NULL)) bc_vm_fatalError(BC_ERR_FATAL_ALLOC_ERR); } return s; } #if !BC_ENABLE_LIBRARY void bc_vm_printf(const char *fmt, ...) { va_list args; + sig_atomic_t lock; - BC_SIG_LOCK; + BC_SIG_TRYLOCK(lock); va_start(args, fmt); bc_file_vprintf(&vm.fout, fmt, args); va_end(args); vm.nchars = 0; - BC_SIG_UNLOCK; + BC_SIG_TRYUNLOCK(lock); } #endif // !BC_ENABLE_LIBRARY void bc_vm_putchar(int c, BcFlushType type) { #if BC_ENABLE_LIBRARY bc_vec_pushByte(&vm.out, (uchar) c); #else // BC_ENABLE_LIBRARY bc_file_putchar(&vm.fout, type, (uchar) c); vm.nchars = (c == '\n' ? 0 : vm.nchars + 1); #endif // BC_ENABLE_LIBRARY } #if !BC_ENABLE_LIBRARY #ifdef __OpenBSD__ /** * Aborts with a message. This should never be called because I have carefully * made sure that the calls to pledge() and unveil() are correct, but it's here * just in case. * @param msg The message to print. */ BC_NORETURN static void bc_abortm(const char* msg) { bc_file_puts(&vm.ferr, bc_flush_none, msg); bc_file_puts(&vm.ferr, bc_flush_none, "; this is a bug"); bc_file_flush(&vm.ferr, bc_flush_none); abort(); } void bc_pledge(const char *promises, const char* execpromises) { int r = pledge(promises, execpromises); if (r) bc_abortm("pledge() failed"); } #if BC_ENABLE_EXTRA_MATH /** * A convenience and portability function for OpenBSD's unveil(). * @param path The path. * @param permissions The permissions for the path. */ static void bc_unveil(const char *path, const char *permissions) { int r = unveil(path, permissions); if (r) bc_abortm("unveil() failed"); } #endif // BC_ENABLE_EXTRA_MATH #else // __OpenBSD__ void bc_pledge(const char *promises, const char *execpromises) { BC_UNUSED(promises); BC_UNUSED(execpromises); } #if BC_ENABLE_EXTRA_MATH static void bc_unveil(const char *path, const char *permissions) { BC_UNUSED(path); BC_UNUSED(permissions); } #endif // BC_ENABLE_EXTRA_MATH #endif // __OpenBSD__ /** * Cleans unneeded variables, arrays, functions, strings, and constants when * done executing a line of stdin. This is to prevent memory usage growing * without bound. This is an idea from busybox. */ static void bc_vm_clean(void) { BcVec *fns = &vm.prog.fns; BcFunc *f = bc_vec_item(fns, BC_PROG_MAIN); BcInstPtr *ip = bc_vec_item(&vm.prog.stack, 0); bool good = ((vm.status && vm.status != BC_STATUS_QUIT) || vm.sig); + BC_SIG_ASSERT_LOCKED; + // If all is good, go ahead and reset. if (good) bc_program_reset(&vm.prog); #if BC_ENABLED // bc has this extra condition. If it not satisfied, it is in the middle of // a parse. if (good && BC_IS_BC) good = !BC_PARSE_NO_EXEC(&vm.prs); #endif // BC_ENABLED #if DC_ENABLED // For dc, it is safe only when all of the results on the results stack are // safe, which means that they are temporaries or other things that don't // need strings or constants. if (BC_IS_DC) { size_t i; good = true; for (i = 0; good && i < vm.prog.results.len; ++i) { BcResult *r = (BcResult*) bc_vec_item(&vm.prog.results, i); good = BC_VM_SAFE_RESULT(r); } } #endif // DC_ENABLED // If this condition is true, we can get rid of strings, // constants, and code. if (good && vm.prog.stack.len == 1 && ip->idx == f->code.len) { #if BC_ENABLED if (BC_IS_BC) { bc_vec_popAll(&f->labels); bc_vec_popAll(&f->strs); bc_vec_popAll(&f->consts); // I can't clear out the other_slabs because it has functions, // consts, strings, vars, and arrays. It has strings from *other* // functions, specifically. bc_slabvec_clear(&vm.main_const_slab); bc_slabvec_clear(&vm.main_slabs); } #endif // BC_ENABLED #if DC_ENABLED // Note to self: you cannot delete strings and functions. Deal with it. if (BC_IS_DC) { bc_vec_popAll(vm.prog.consts); bc_slabvec_clear(&vm.main_const_slab); } #endif // DC_ENABLED bc_vec_popAll(&f->code); ip->idx = 0; } } /** * Process a bunch of text. * @param text The text to process. * @param is_stdin True if the text came from stdin, false otherwise. */ static void bc_vm_process(const char *text, bool is_stdin) { // Set up the parser. bc_parse_text(&vm.prs, text, is_stdin); do { + BC_SIG_LOCK; + #if BC_ENABLED // If the first token is the keyword define, then we need to do this // specially because bc thinks it may not be able to parse. if (vm.prs.l.t == BC_LEX_KW_DEFINE) vm.parse(&vm.prs); #endif // BC_ENABLED // Parse it all. while (BC_PARSE_CAN_PARSE(vm.prs)) vm.parse(&vm.prs); + BC_SIG_UNLOCK; + // Execute if possible. if(BC_IS_DC || !BC_PARSE_NO_EXEC(&vm.prs)) bc_program_exec(&vm.prog); assert(BC_IS_DC || vm.prog.results.len == 0); // Flush in interactive mode. if (BC_I) bc_file_flush(&vm.fout, bc_flush_save); } while (vm.prs.l.t != BC_LEX_EOF); } #if BC_ENABLED /** * Ends a series of if statements. This is to ensure that full parses happen * when a file finishes or stdin has no more data. Without this, bc thinks that * it cannot parse any further. But if we reach the end of a file or stdin has * no more data, we know we can add an empty else clause. */ static void bc_vm_endif(void) { bc_parse_endif(&vm.prs); bc_program_exec(&vm.prog); } #endif // BC_ENABLED /** * Processes a file. * @param file The filename. */ static void bc_vm_file(const char *file) { char *data = NULL; assert(!vm.sig_pop); // Set up the lexer. bc_lex_file(&vm.prs.l, file); BC_SIG_LOCK; // Read the file. data = bc_read_file(file); assert(data != NULL); BC_SETJMP_LOCKED(err); BC_SIG_UNLOCK; // Process it. bc_vm_process(data, false); #if BC_ENABLED // Make sure to end any open if statements. if (BC_IS_BC) bc_vm_endif(); #endif // BC_ENABLED err: BC_SIG_MAYLOCK; // Cleanup. free(data); bc_vm_clean(); // bc_program_reset(), called by bc_vm_clean(), resets the status. // We want it to clear the sig_pop variable in case it was set. if (vm.status == (sig_atomic_t) BC_STATUS_SUCCESS) BC_LONGJMP_STOP; BC_LONGJMP_CONT; } bool bc_vm_readLine(bool clear) { BcStatus s; bool good; + BC_SIG_ASSERT_NOT_LOCKED; + // Clear the buffer if desired. if (clear) bc_vec_empty(&vm.buffer); // Empty the line buffer. bc_vec_empty(&vm.line_buf); if (vm.eof) return false; do { // bc_read_line() must always return either BC_STATUS_SUCCESS or // BC_STATUS_EOF. Everything else, it and whatever it calls, must jump // out instead. s = bc_read_line(&vm.line_buf, ">>> "); vm.eof = (s == BC_STATUS_EOF); } while (!(s) && !vm.eof && vm.line_buf.len < 1); good = (vm.line_buf.len > 1); // Concat if we found something. if (good) bc_vec_concat(&vm.buffer, vm.line_buf.v); return good; } /** * Processes text from stdin. */ static void bc_vm_stdin(void) { bool clear = true; vm.is_stdin = true; // Set up the lexer. bc_lex_file(&vm.prs.l, bc_program_stdin_name); // These are global so that the dc lexer can access them, but they are tied // to this function, really. Well, this and bc_vm_readLine(). These are the // reason that we have vm.is_stdin to tell the dc lexer if we are reading // from stdin. Well, both lexers care. And the reason they care is so that // if a comment or a string goes across multiple lines, the lexer can // request more data from stdin until the comment or string is ended. BC_SIG_LOCK; bc_vec_init(&vm.buffer, sizeof(uchar), BC_DTOR_NONE); bc_vec_init(&vm.line_buf, sizeof(uchar), BC_DTOR_NONE); BC_SETJMP_LOCKED(err); BC_SIG_UNLOCK; // This label exists because errors can cause jumps to end up at the err label // below. If that happens, and the error should be cleared and execution // continue, then we need to jump back. restart: // While we still read data from stdin. while (bc_vm_readLine(clear)) { size_t len = vm.buffer.len - 1; const char *str = vm.buffer.v; // We don't want to clear the buffer when the line ends with a backslash // because a backslash newline is special in bc. clear = (len < 2 || str[len - 2] != '\\' || str[len - 1] != '\n'); if (!clear) continue; // Process the data. bc_vm_process(vm.buffer.v, true); if (vm.eof) break; - else bc_vm_clean(); + else { + BC_SIG_LOCK; + bc_vm_clean(); + BC_SIG_UNLOCK; + } } #if BC_ENABLED // End the if statements. if (BC_IS_BC) bc_vm_endif(); #endif // BC_ENABLED err: BC_SIG_MAYLOCK; // Cleanup. bc_vm_clean(); #if !BC_ENABLE_MEMCHECK assert(vm.status != BC_STATUS_ERROR_FATAL); vm.status = vm.status == BC_STATUS_QUIT || !BC_I ? vm.status : BC_STATUS_SUCCESS; #else // !BC_ENABLE_MEMCHECK vm.status = vm.status == BC_STATUS_ERROR_FATAL || vm.status == BC_STATUS_QUIT || !BC_I ? vm.status : BC_STATUS_SUCCESS; #endif // !BC_ENABLE_MEMCHECK if (!vm.status && !vm.eof) { bc_vec_empty(&vm.buffer); BC_LONGJMP_STOP; BC_SIG_UNLOCK; goto restart; } #ifndef NDEBUG // Since these are tied to this function, free them here. bc_vec_free(&vm.line_buf); bc_vec_free(&vm.buffer); #endif // NDEBUG BC_LONGJMP_CONT; } #if BC_ENABLED /** * Loads a math library. * @param name The name of the library. * @param text The text of the source code. */ static void bc_vm_load(const char *name, const char *text) { bc_lex_file(&vm.prs.l, name); bc_parse_text(&vm.prs, text, false); + BC_SIG_LOCK; + while (vm.prs.l.t != BC_LEX_EOF) vm.parse(&vm.prs); + + BC_SIG_UNLOCK; } #endif // BC_ENABLED /** * Loads the default error messages. */ static void bc_vm_defaultMsgs(void) { size_t i; vm.func_header = bc_err_func_header; // Load the error categories. for (i = 0; i < BC_ERR_IDX_NELEMS + BC_ENABLED; ++i) vm.err_ids[i] = bc_errs[i]; // Load the error messages. for (i = 0; i < BC_ERR_NELEMS; ++i) vm.err_msgs[i] = bc_err_msgs[i]; } /** * Loads the error messages for the locale. If NLS is disabled, this just loads * the default messages. */ static void bc_vm_gettext(void) { #if BC_ENABLE_NLS uchar id = 0; int set = 1, msg = 1; size_t i; // If no locale, load the defaults. if (vm.locale == NULL) { vm.catalog = BC_VM_INVALID_CATALOG; bc_vm_defaultMsgs(); return; } vm.catalog = catopen(BC_MAINEXEC, NL_CAT_LOCALE); // If no catalog, load the defaults. if (vm.catalog == BC_VM_INVALID_CATALOG) { bc_vm_defaultMsgs(); return; } // Load the function header. vm.func_header = catgets(vm.catalog, set, msg, bc_err_func_header); // Load the error categories. for (set += 1; msg <= BC_ERR_IDX_NELEMS + BC_ENABLED; ++msg) vm.err_ids[msg - 1] = catgets(vm.catalog, set, msg, bc_errs[msg - 1]); i = 0; id = bc_err_ids[i]; // Load the error messages. In order to understand this loop, you must know // the order of messages and categories in the enum and in the locale files. for (set = id + 3, msg = 1; i < BC_ERR_NELEMS; ++i, ++msg) { if (id != bc_err_ids[i]) { msg = 1; id = bc_err_ids[i]; set = id + 3; } vm.err_msgs[i] = catgets(vm.catalog, set, msg, bc_err_msgs[i]); } #else // BC_ENABLE_NLS bc_vm_defaultMsgs(); #endif // BC_ENABLE_NLS } /** * Starts execution. Really, this is a function of historical accident; it could * probably be combined with bc_vm_boot(), but I don't care enough. Really, this * function starts when execution of bc or dc source code starts. */ static void bc_vm_exec(void) { size_t i; bool has_file = false; BcVec buf; #if BC_ENABLED // Load the math libraries. if (BC_IS_BC && (vm.flags & BC_FLAG_L)) { // Can't allow redefinitions in the builtin library. vm.no_redefine = true; bc_vm_load(bc_lib_name, bc_lib); #if BC_ENABLE_EXTRA_MATH if (!BC_IS_POSIX) bc_vm_load(bc_lib2_name, bc_lib2); #endif // BC_ENABLE_EXTRA_MATH // Make sure to clear this. vm.no_redefine = false; // Execute to ensure that all is hunky dory. Without this, scale can be // set improperly. bc_program_exec(&vm.prog); } #endif // BC_ENABLED // If there are expressions to execute... if (vm.exprs.len) { size_t len = vm.exprs.len - 1; bool more; BC_SIG_LOCK; // Create this as a buffer for reading into. bc_vec_init(&buf, sizeof(uchar), BC_DTOR_NONE); #ifndef NDEBUG BC_SETJMP_LOCKED(err); #endif // NDEBUG BC_SIG_UNLOCK; // Prepare the lexer. bc_lex_file(&vm.prs.l, bc_program_exprs_name); // Process the expressions one at a time. do { more = bc_read_buf(&buf, vm.exprs.v, &len); bc_vec_pushByte(&buf, '\0'); bc_vm_process(buf.v, false); bc_vec_popAll(&buf); } while (more); BC_SIG_LOCK; bc_vec_free(&buf); #ifndef NDEBUG BC_UNSETJMP; #endif // NDEBUG BC_SIG_UNLOCK; // Sometimes, executing expressions means we need to quit. - if (!vm.no_exprs && vm.exit_exprs) return; + if (!vm.no_exprs && vm.exit_exprs && BC_EXPR_EXIT) return; } // Process files. for (i = 0; i < vm.files.len; ++i) { char *path = *((char**) bc_vec_item(&vm.files, i)); if (!strcmp(path, "")) continue; has_file = true; bc_vm_file(path); } #if BC_ENABLE_EXTRA_MATH // These are needed for the pseudo-random number generator. bc_unveil("/dev/urandom", "r"); bc_unveil("/dev/random", "r"); bc_unveil(NULL, NULL); #endif // BC_ENABLE_EXTRA_MATH #if BC_ENABLE_HISTORY // We need to keep tty if history is enabled, and we need to keep rpath for // the times when we read from /dev/urandom. - if (BC_TTY && !vm.history.badTerm) { - bc_pledge(bc_pledge_end_history, NULL); - } + if (BC_TTY && !vm.history.badTerm) bc_pledge(bc_pledge_end_history, NULL); else #endif // BC_ENABLE_HISTORY { bc_pledge(bc_pledge_end, NULL); } #if BC_ENABLE_AFL // This is the thing that makes fuzzing with AFL++ so fast. If you move this // back, you won't cause any problems, but fuzzing will slow down. If you // move this forward, you won't fuzz anything because you will be skipping // the reading from stdin. __AFL_INIT(); #endif // BC_ENABLE_AFL // Execute from stdin. bc always does. if (BC_IS_BC || !has_file) bc_vm_stdin(); // These are all protected by ifndef NDEBUG because if these are needed, bc is // going to exit anyway, and I see no reason to include this code in a release // build when the OS is going to free all of the resources anyway. #ifndef NDEBUG return; err: BC_SIG_MAYLOCK; bc_vec_free(&buf); BC_LONGJMP_CONT; #endif // NDEBUG } void bc_vm_boot(int argc, char *argv[]) { int ttyin, ttyout, ttyerr; bool tty; const char* const env_len = BC_IS_BC ? "BC_LINE_LENGTH" : "DC_LINE_LENGTH"; const char* const env_args = BC_IS_BC ? "BC_ENV_ARGS" : "DC_ENV_ARGS"; + const char* const env_exit = BC_IS_BC ? "BC_EXPR_EXIT" : "DC_EXPR_EXIT"; + int env_exit_def = BC_IS_BC ? BC_DEFAULT_EXPR_EXIT : DC_DEFAULT_EXPR_EXIT; // We need to know which of stdin, stdout, and stderr are tty's. ttyin = isatty(STDIN_FILENO); ttyout = isatty(STDOUT_FILENO); ttyerr = isatty(STDERR_FILENO); tty = (ttyin != 0 && ttyout != 0 && ttyerr != 0); vm.flags |= ttyin ? BC_FLAG_TTYIN : 0; vm.flags |= tty ? BC_FLAG_TTY : 0; vm.flags |= ttyin && ttyout ? BC_FLAG_I : 0; // Set up signals. bc_vm_sigaction(); // Initialize some vm stuff. This is separate to make things easier for the // library. bc_vm_init(); // Explicitly set this in case NULL isn't all zeroes. vm.file = NULL; // Set the error messages. bc_vm_gettext(); // Initialize the output file buffers. They each take portions of the global // buffer. stdout gets more because it will probably have more data. bc_file_init(&vm.ferr, STDERR_FILENO, output_bufs + BC_VM_STDOUT_BUF_SIZE, BC_VM_STDERR_BUF_SIZE); bc_file_init(&vm.fout, STDOUT_FILENO, output_bufs, BC_VM_STDOUT_BUF_SIZE); // Set the input buffer to the rest of the global buffer. vm.buf = output_bufs + BC_VM_STDOUT_BUF_SIZE + BC_VM_STDERR_BUF_SIZE; // Set the line length by environment variable. vm.line_len = (uint16_t) bc_vm_envLen(env_len); + bc_vm_setenvFlag(env_exit, env_exit_def, BC_FLAG_EXPR_EXIT); + // Clear the files and expressions vectors, just in case. This marks them as // *not* allocated. bc_vec_clear(&vm.files); bc_vec_clear(&vm.exprs); #if !BC_ENABLE_LIBRARY // Initialize the slab vectors. bc_slabvec_init(&vm.main_const_slab); bc_slabvec_init(&vm.main_slabs); bc_slabvec_init(&vm.other_slabs); #endif // !BC_ENABLE_LIBRARY // Initialize the program and main parser. These have to be in this order // because the program has to be initialized first, since a pointer to it is // passed to the parser. bc_program_init(&vm.prog); bc_parse_init(&vm.prs, &vm.prog, BC_PROG_MAIN); + // Set defaults. + vm.flags |= BC_TTY ? BC_FLAG_P | BC_FLAG_R : 0; + vm.flags |= BC_I ? BC_FLAG_Q : 0; + #if BC_ENABLED - // bc checks this environment variable to see if it should run in standard - // mode. if (BC_IS_BC) { + // bc checks this environment variable to see if it should run in + // standard mode. char* var = bc_vm_getenv("POSIXLY_CORRECT"); vm.flags |= BC_FLAG_S * (var != NULL); bc_vm_getenvFree(var); - } -#endif // BC_ENABLED - - // Set defaults. - vm.flags |= BC_TTY ? BC_FLAG_P | BC_FLAG_R : 0; - vm.flags |= BC_I ? BC_FLAG_Q : 0; -#if BC_ENABLED - if (BC_IS_BC && BC_I) { // Set whether we print the banner or not. - bc_vm_setenvFlag("BC_BANNER", BC_DEFAULT_BANNER, BC_FLAG_Q); + if (BC_I) bc_vm_setenvFlag("BC_BANNER", BC_DEFAULT_BANNER, BC_FLAG_Q); } #endif // BC_ENABLED // Are we in TTY mode? if (BC_TTY) { const char* const env_tty = BC_IS_BC ? "BC_TTY_MODE" : "DC_TTY_MODE"; int env_tty_def = BC_IS_BC ? BC_DEFAULT_TTY_MODE : DC_DEFAULT_TTY_MODE; const char* const env_prompt = BC_IS_BC ? "BC_PROMPT" : "DC_PROMPT"; int env_prompt_def = BC_IS_BC ? BC_DEFAULT_PROMPT : DC_DEFAULT_PROMPT; // Set flags for TTY mode and prompt. bc_vm_setenvFlag(env_tty, env_tty_def, BC_FLAG_TTY); bc_vm_setenvFlag(env_prompt, tty ? env_prompt_def : 0, BC_FLAG_P); #if BC_ENABLE_HISTORY // If TTY mode is used, activate history. if (BC_TTY) bc_history_init(&vm.history); #endif // BC_ENABLE_HISTORY } // Process environment and command-line arguments. bc_vm_envArgs(env_args); bc_args(argc, argv, true); // If we are in interactive mode... if (BC_I) { const char* const env_sigint = BC_IS_BC ? "BC_SIGINT_RESET" : "DC_SIGINT_RESET"; int env_sigint_def = BC_IS_BC ? BC_DEFAULT_SIGINT_RESET : DC_DEFAULT_SIGINT_RESET; // Set whether we reset on SIGINT or not. bc_vm_setenvFlag(env_sigint, env_sigint_def, BC_FLAG_SIGINT); } #if BC_ENABLED // Disable global stacks in POSIX mode. if (BC_IS_POSIX) vm.flags &= ~(BC_FLAG_G); -#endif // BC_ENABLED -#if BC_ENABLED // Print the banner if allowed. We have to be in bc, in interactive mode, // and not be quieted by command-line option or environment variable. if (BC_IS_BC && BC_I && (vm.flags & BC_FLAG_Q)) { bc_vm_info(NULL); bc_file_putchar(&vm.fout, bc_flush_none, '\n'); bc_file_flush(&vm.fout, bc_flush_none); } #endif // BC_ENABLED BC_SIG_UNLOCK; // Start executing. bc_vm_exec(); } #endif // !BC_ENABLE_LIBRARY void bc_vm_init(void) { BC_SIG_ASSERT_LOCKED; #if !BC_ENABLE_LIBRARY // Set up the constant zero. bc_num_setup(&vm.zero, vm.zero_num, BC_VM_ONE_CAP); #endif // !BC_ENABLE_LIBRARY // Set up more constant BcNum's. bc_num_setup(&vm.one, vm.one_num, BC_VM_ONE_CAP); bc_num_one(&vm.one); // Set up more constant BcNum's. memcpy(vm.max_num, bc_num_bigdigMax, bc_num_bigdigMax_size * sizeof(BcDig)); memcpy(vm.max2_num, bc_num_bigdigMax2, bc_num_bigdigMax2_size * sizeof(BcDig)); bc_num_setup(&vm.max, vm.max_num, BC_NUM_BIGDIG_LOG10); bc_num_setup(&vm.max2, vm.max2_num, BC_NUM_BIGDIG_LOG10); vm.max.len = bc_num_bigdigMax_size; vm.max2.len = bc_num_bigdigMax2_size; // Set up the maxes for the globals. vm.maxes[BC_PROG_GLOBALS_IBASE] = BC_NUM_MAX_POSIX_IBASE; vm.maxes[BC_PROG_GLOBALS_OBASE] = BC_MAX_OBASE; vm.maxes[BC_PROG_GLOBALS_SCALE] = BC_MAX_SCALE; #if BC_ENABLE_EXTRA_MATH vm.maxes[BC_PROG_MAX_RAND] = ((BcRand) 0) - 1; #endif // BC_ENABLE_EXTRA_MATH #if BC_ENABLED #if !BC_ENABLE_LIBRARY // bc has a higher max ibase when it's not in POSIX mode. if (BC_IS_BC && !BC_IS_POSIX) #endif // !BC_ENABLE_LIBRARY { vm.maxes[BC_PROG_GLOBALS_IBASE] = BC_NUM_MAX_IBASE; } #endif // BC_ENABLED } #if BC_ENABLE_LIBRARY void bc_vm_atexit(void) { bc_vm_shutdown(); #ifndef NDEBUG bc_vec_free(&vm.jmp_bufs); #endif // NDEBUG } #else // BC_ENABLE_LIBRARY int bc_vm_atexit(int status) { // Set the status correctly. int s = BC_STATUS_IS_ERROR(status) ? status : BC_STATUS_SUCCESS; bc_vm_shutdown(); #ifndef NDEBUG bc_vec_free(&vm.jmp_bufs); #endif // NDEBUG return s; } #endif // BC_ENABLE_LIBRARY diff --git a/contrib/bc/tests/bc/all.txt b/contrib/bc/tests/bc/all.txt index 23244773b933..f85491d12424 100644 --- a/contrib/bc/tests/bc/all.txt +++ b/contrib/bc/tests/bc/all.txt @@ -1,52 +1,53 @@ decimal print parse lib2 print2 length scale shift add subtract multiply divide modulus power sqrt trunc places vars boolean comp abs assignments functions scientific engineering globals strings strings2 letters exponent log pi arctangent sine cosine bessel arrays misc misc1 misc2 misc3 misc4 misc5 misc6 misc7 +misc8 void rand recursive_arrays divmod modexp bitfuncs leadingzero diff --git a/contrib/bc/tests/bc/misc8.txt b/contrib/bc/tests/bc/misc8.txt new file mode 100644 index 000000000000..8bef63316ef8 --- /dev/null +++ b/contrib/bc/tests/bc/misc8.txt @@ -0,0 +1,8 @@ +define a(){ + return 5 +}define b(){ + return 6 +} +24 +a() +b() diff --git a/contrib/bc/tests/bc/misc8_results.txt b/contrib/bc/tests/bc/misc8_results.txt new file mode 100644 index 000000000000..daee0f1b2fbf --- /dev/null +++ b/contrib/bc/tests/bc/misc8_results.txt @@ -0,0 +1,3 @@ +24 +5 +6 diff --git a/contrib/bc/tests/bc/posix_errors.txt b/contrib/bc/tests/bc/posix_errors.txt index d880600f7bb1..584a0198b5b3 100644 --- a/contrib/bc/tests/bc/posix_errors.txt +++ b/contrib/bc/tests/bc/posix_errors.txt @@ -1,32 +1,33 @@ aa = 0 # This is a comment. while (q==0) { ++q; continue; } last print "i: ", i halt define x(e) { return 0; } define x(e) { return 4*(e+e); } define x(e) { return (e+e)*4; } +define a() { return (5); };define b() { return (6); } limits . if (q!=0) { x=3; } else { x=4; } x<=0 while (q!=0 && x==0) { ++q; } while (q!=0 || x==0) { ++q; } while (!q) { ++q; } for (; x<0; ++x) { y += 1; } for (x=0;; ++x) { y += 1; } for (x=0; x<0;) { y += 1; } for (x=0;;) { y += 1; } for (; x<0;) { y += 1; } for (;; ++x) { y += 1; } for (;;) { y += 1; } 3e2981 9.892108e-20 obase = 0 obase = 1 define void a(e) { "stuff" } maxibase() maxobase() maxscale() v = "stuff" diff --git a/contrib/bc/tests/bc/timeconst.sh b/contrib/bc/tests/bc/timeconst.sh index 45e10c77bdf4..8b6e1ec596fc 100755 --- a/contrib/bc/tests/bc/timeconst.sh +++ b/contrib/bc/tests/bc/timeconst.sh @@ -1,116 +1,115 @@ #! /bin/sh # # Copyright (c) 2018-2021 Gavin D. Howard and contributors. # # Redistribution and use in source and binary forms, with or without # modification, are permitted provided that the following conditions are met: # # * Redistributions of source code must retain the above copyright notice, this # list of conditions and the following disclaimer. # # * Redistributions in binary form must reproduce the above copyright notice, # this list of conditions and the following disclaimer in the documentation # and/or other materials provided with the distribution. # # THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" # AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE # IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE # ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE # LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR # CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF # SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS # INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN # CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) # ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE # POSSIBILITY OF SUCH DAMAGE. # # Tests the timeconst.bc script from the Linux kernel build. # You can find the script at kernel/time/timeconst.bc in any Linux repo. # One such repo is: https://github.com/torvalds/linux script="$0" testdir=$(dirname "$script") outputdir=${BC_TEST_OUTPUT_DIR:-$testdir/..} # Gets the timeconst script, which could be a command-line argument. if [ "$#" -gt 0 ]; then timeconst="$1" shift else timeconst="$testdir/scripts/timeconst.bc" fi # Gets the executable, which could also be a command-line argument. if [ "$#" -gt 0 ]; then bc="$1" shift else bc="$testdir/../../bin/bc" fi -# out1="$outputdir/bc_outputs/bc_timeconst.txt" out2="$outputdir/bc_outputs/bc_timeconst_results.txt" outdir=$(dirname "$out1") # Make sure the directory exists. if [ ! -d "$outdir" ]; then mkdir -p "$outdir" fi base=$(basename "$timeconst") # If the script does not exist, just skip. Running this test is not necessary. if [ ! -f "$timeconst" ]; then printf 'Warning: %s does not exist\n' "$timeconst" printf 'Skipping...\n' exit 0 fi # I use these, so unset them to make the tests work. unset BC_ENV_ARGS unset BC_LINE_LENGTH unset DC_ENV_ARGS unset DC_LINE_LENGTH printf 'Running %s...' "$base" # Get a list of numbers. Funny how bc can help with that. nums=$(printf 'for (i = 0; i <= 1000; ++i) { i }\n' | bc) # Run each number through the script. for i in $nums; do # Run the GNU bc on the test. printf '%s\n' "$i" | bc -q "$timeconst" > "$out1" err="$?" # If the other bc failed, it's not GNU bc, or this bc. if [ "$err" -ne 0 ]; then printf '\nOther bc is not GNU compatible. Skipping...\n' exit 0 fi # Run the built bc on the test. printf '%s\n' "$i" | "$bc" "$@" -q "$timeconst" > "$out2" diff "$out1" "$out2" error="$?" # If fail, bail. if [ "$error" -ne 0 ]; then printf '\nFailed on input: %s\n' "$i" exit "$error" fi done rm -f "$out1" rm -f "$out2" exec printf 'pass\n' diff --git a/contrib/bc/tests/history.py b/contrib/bc/tests/history.py index 17006c93ef2d..84e32f9612c4 100755 --- a/contrib/bc/tests/history.py +++ b/contrib/bc/tests/history.py @@ -1,1153 +1,1154 @@ #! /usr/bin/python # # SPDX-License-Identifier: BSD-2-Clause # # Copyright (c) 2018-2021 Gavin D. Howard and contributors. # # Redistribution and use in source and binary forms, with or without # modification, are permitted provided that the following conditions are met: # # * Redistributions of source code must retain the above copyright notice, this # list of conditions and the following disclaimer. # # * Redistributions in binary form must reproduce the above copyright notice, # this list of conditions and the following disclaimer in the documentation # and/or other materials provided with the distribution. # # THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" # AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE # IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE # ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE # LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR # CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF # SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS # INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN # CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) # ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE # POSSIBILITY OF SUCH DAMAGE. # import os, sys import time import signal import traceback try: import pexpect except ImportError: print("Could not find pexpect. Skipping...") sys.exit(0) # Housekeeping. script = sys.argv[0] testdir = os.path.dirname(script) if "BC_TEST_OUTPUT_DIR" in os.environ: outputdir = os.environ["BC_TEST_OUTPUT_DIR"] else: outputdir = testdir prompt = ">>> " # This array is for escaping characters that are necessary to escape when # outputting to pexpect. Since pexpect takes regexes, these characters confuse # it unless we escape them. escapes = [ ']', '[', '+', ] # UTF-8 stress tests. utf8_stress1 = "ᆬḰ䋔䗅㜲ತ咡䒢岤䳰稨⣡嶣㷡嶏ⵐ䄺嵕ਅ奰痚㆜䊛拂䅙૩➋䛿ቬ竳Ϳᅠ❄产翷䮊௷Ỉ䷒䳜㛠➕傎ᗋᏯਕ䆐悙癐㺨" utf8_stress2 = "韠싧돳넨큚ꉿ뮴픷ꉲ긌�최릙걆鳬낽ꪁ퍼鈴핐黙헶ꪈ뮩쭀锻끥鉗겉욞며뛯꬐�ﻼ�度錐�" utf8_stress3 = "곻�䣹昲蜴Ὓ桢㎏⚦珢畣갴ﭱ鶶ๅ⶛뀁彻ꖒ䔾ꢚﱤ햔햞㐹�鼳뵡▿ⶾ꠩�纞⊐佧�ⵟ霘紳㱔籠뎼⊓搧硤" utf8_stress4 = "ᄀ𖢾🏴��" # An easy array for UTF-8 tests. utf8_stress_strs = [ utf8_stress1, utf8_stress2, utf8_stress3, utf8_stress4, ] def expect(child, data): child.expect(data) # Eats all of the child's data. # @param child The child whose data should be eaten. def eat(child): while child.buffer is not None and len(child.buffer) > 0: expect(child, ".+") # Send data to a child. This makes sure the buffers are empty first. # @param child The child to send data to. # @param data The data to send. def send(child, data): eat(child) child.send(data) def wait(child): if child.isalive(): child.sendeof() time.sleep(1) if child.isalive(): child.kill(signal.SIGTERM) time.sleep(1) if child.isalive(): child.kill(signal.SIGKILL) child.wait() # Check that the child output the expected line. If history is false, then # the output should change. def check_line(child, expected, prompt=">>> ", history=True): send(child, "\n") prefix = "\r\n" if history else "" expect(child, prefix + expected + "\r\n" + prompt) # Write a string to output, checking all of the characters are output, # one-by-one. def write_str(child, s): for c in s: send(child, c) if c in escapes: expect(child, "\\{}".format(c)) else: expect(child, c) # Check the bc banner. # @param child The child process. def bc_banner(child): bc_banner1 = "bc [0-9]+\.[0-9]+\.[0-9]+\r\n" bc_banner2 = "Copyright \(c\) 2018-[2-9][0-9][0-9][0-9] Gavin D. Howard and contributors\r\n" bc_banner3 = "Report bugs at: https://git.yzena.com/gavin/bc\r\n\r\n" bc_banner4 = "This is free software with ABSOLUTELY NO WARRANTY.\r\n\r\n" expect(child, bc_banner1) expect(child, bc_banner2) expect(child, bc_banner3) expect(child, bc_banner4) expect(child, prompt) # Common UTF-8 testing function. The index is the index into utf8_stress_strs # for which stress string to use. # @param exe The executable. # @param args The arguments to pass to the executable. # @param env The environment. # @param idx The index of the UTF-8 stress string. def test_utf8(exe, args, env, idx, bc=True): # Because both bc and dc use this, make sure the banner doesn't pop. env["BC_BANNER"] = "0" child = pexpect.spawn(exe, args=args, env=env, encoding='utf-8', codec_errors='ignore') try: # Write the stress string. send(child, utf8_stress_strs[idx]) send(child, "\n") if bc: send(child, "quit") else: send(child, "q") send(child, "\n") wait(child) except pexpect.TIMEOUT: traceback.print_tb(sys.exc_info()[2]) print("timed out") print(str(child)) sys.exit(2) except pexpect.EOF: print("EOF") print(str(child)) print(str(child.buffer)) print(str(child.before)) sys.exit(2) return child # A random UTF-8 test with insert. # @param exe The executable. # @param args The arguments to pass to the executable. # @param env The environment. def test_utf8_0(exe, args, env, bc=True): # Because both bc and dc use this, make sure the banner doesn't pop. env["BC_BANNER"] = "0" child = pexpect.spawn(exe, args=args, env=env, encoding='utf-8', codec_errors='ignore') try: # Just random UTF-8 I generated somewhow, plus ensuring that insert works. write_str(child, "ﴪáá̵̗🈐ã") send(child, "\x1b[D\x1b[D\x1b[D\x1b\x1b[Aℐ") send(child, "\n") if bc: send(child, "quit") else: send(child, "q") send(child, "\n") eat(child) wait(child) except pexpect.TIMEOUT: traceback.print_tb(sys.exc_info()[2]) print("timed out") print(str(child)) sys.exit(2) except pexpect.EOF: print("EOF") print(str(child)) print(str(child.buffer)) print(str(child.before)) sys.exit(2) return child def test_utf8_1(exe, args, env, bc=True): return test_utf8(exe, args, env, 0, bc) def test_utf8_2(exe, args, env, bc=True): return test_utf8(exe, args, env, 1, bc) def test_utf8_3(exe, args, env, bc=True): return test_utf8(exe, args, env, 2, bc) def test_utf8_4(exe, args, env, bc=True): return test_utf8(exe, args, env, 3, bc) # This tests a SIGINT with reset followed by a SIGQUIT. # @param exe The executable. # @param args The arguments to pass to the executable. # @param env The environment. def test_sigint_sigquit(exe, args, env): # Because both bc and dc use this, make sure the banner doesn't pop. env["BC_BANNER"] = "0" child = pexpect.spawn(exe, args=args, env=env) try: send(child, "\t") expect(child, " ") send(child, "\x03") - send(child, "\x1c") + # send(child, "\x1c") wait(child) except pexpect.TIMEOUT: traceback.print_tb(sys.exc_info()[2]) print("timed out") print(str(child)) sys.exit(2) except pexpect.EOF: print("EOF") print(str(child)) print(str(child.buffer)) print(str(child.before)) sys.exit(2) return child # Test for EOF. # @param exe The executable. # @param args The arguments to pass to the executable. # @param env The environment. def test_eof(exe, args, env): # Because both bc and dc use this, make sure the banner doesn't pop. env["BC_BANNER"] = "0" child = pexpect.spawn(exe, args=args, env=env) try: send(child, "\t") expect(child, " ") send(child, "\x04") wait(child) except pexpect.TIMEOUT: traceback.print_tb(sys.exc_info()[2]) print("timed out") print(str(child)) sys.exit(2) except pexpect.EOF: print("EOF") print(str(child)) print(str(child.buffer)) print(str(child.before)) sys.exit(2) return child # Test for quiting SIGINT. # @param exe The executable. # @param args The arguments to pass to the executable. # @param env The environment. def test_sigint(exe, args, env): # Because both bc and dc use this, make sure the banner doesn't pop. env["BC_BANNER"] = "0" env["BC_SIGINT_RESET"] = "0" env["DC_SIGINT_RESET"] = "0" child = pexpect.spawn(exe, args=args, env=env) try: send(child, "\t") expect(child, " ") send(child, "\x03") wait(child) except pexpect.TIMEOUT: traceback.print_tb(sys.exc_info()[2]) print("timed out") print(str(child)) sys.exit(2) except pexpect.EOF: print("EOF") print(str(child)) print(str(child.buffer)) print(str(child.before)) sys.exit(2) return child # Test for SIGTSTP. # @param exe The executable. # @param args The arguments to pass to the executable. # @param env The environment. def test_sigtstp(exe, args, env): # This test does not work on FreeBSD, so skip. if sys.platform.startswith("freebsd"): sys.exit(0) # Because both bc and dc use this, make sure the banner doesn't pop. env["BC_BANNER"] = "0" child = pexpect.spawn(exe, args=args, env=env) try: send(child, "\t") expect(child, " ") send(child, "\x13") time.sleep(1) if not child.isalive(): print("child exited early") print(str(child)) print(str(child.buffer)) sys.exit(1) child.kill(signal.SIGCONT) send(child, "quit") send(child, "\n") wait(child) except pexpect.TIMEOUT: traceback.print_tb(sys.exc_info()[2]) print("timed out") print(str(child)) sys.exit(2) except pexpect.EOF: print("EOF") print(str(child)) print(str(child.buffer)) print(str(child.before)) sys.exit(2) return child # Test for SIGSTOP. # @param exe The executable. # @param args The arguments to pass to the executable. # @param env The environment. def test_sigstop(exe, args, env): # Because both bc and dc use this, make sure the banner doesn't pop. env["BC_BANNER"] = "0" child = pexpect.spawn(exe, args=args, env=env) try: send(child, "\t") expect(child, " ") send(child, "\x14") time.sleep(1) if not child.isalive(): print("child exited early") print(str(child)) print(str(child.buffer)) sys.exit(1) send(child, "\x13") time.sleep(1) if not child.isalive(): print("child exited early") print(str(child)) print(str(child.buffer)) sys.exit(1) child.kill(signal.SIGCONT) send(child, "quit") send(child, "\n") wait(child) except pexpect.TIMEOUT: traceback.print_tb(sys.exc_info()[2]) print("timed out") print(str(child)) sys.exit(2) except pexpect.EOF: print("EOF") print(str(child)) print(str(child.buffer)) print(str(child.before)) sys.exit(2) return child def test_bc_utf8_0(exe, args, env): return test_utf8_0(exe, args, env, True) def test_bc_utf8_1(exe, args, env): return test_utf8_1(exe, args, env, True) def test_bc_utf8_2(exe, args, env): return test_utf8_2(exe, args, env, True) def test_bc_utf8_3(exe, args, env): return test_utf8_3(exe, args, env, True) def test_bc_utf8_4(exe, args, env): return test_utf8_4(exe, args, env, True) # Basic bc test. # @param exe The executable. # @param args The arguments to pass to the executable. # @param env The environment. def test_bc1(exe, args, env): child = pexpect.spawn(exe, args=args, env=env) try: bc_banner(child) write_str(child, "1") check_line(child, "1") write_str(child, "1") check_line(child, "1") send(child, "quit") send(child, "\n") wait(child) except pexpect.TIMEOUT: traceback.print_tb(sys.exc_info()[2]) print("timed out") print(str(child)) sys.exit(2) except pexpect.EOF: print("EOF") print(str(child)) print(str(child.buffer)) print(str(child.before)) sys.exit(2) return child # SIGINT with no history. # @param exe The executable. # @param args The arguments to pass to the executable. # @param env The environment. def test_bc2(exe, args, env): env["TERM"] = "dumb" child = pexpect.spawn(exe, args=args, env=env) try: bc_banner(child) child.sendline("1") check_line(child, "1", history=False) time.sleep(1) child.sendintr() child.sendline("quit") wait(child) except pexpect.TIMEOUT: traceback.print_tb(sys.exc_info()[2]) print("timed out") print(str(child)) sys.exit(2) except pexpect.EOF: print("EOF") print(str(child)) print(str(child.buffer)) print(str(child.before)) sys.exit(2) return child # Left and right arrows. # @param exe The executable. # @param args The arguments to pass to the executable. # @param env The environment. def test_bc3(exe, args, env): child = pexpect.spawn(exe, args=args, env=env) try: bc_banner(child) send(child, "\x1b[D\x1b[D\x1b[C\x1b[C") send(child, "\n") expect(child, prompt) send(child, "12\x1b[D3\x1b[C4\x1bOD5\x1bOC6") send(child, "\n") check_line(child, "132546") send(child, "12\x023\x064") send(child, "\n") check_line(child, "1324") send(child, "12\x1b[H3\x1bOH\x01\x1b[H45\x1bOF6\x05\x1b[F7\x1bOH8") send(child, "\n") check_line(child, "84531267") send(child, "quit") send(child, "\n") wait(child) except pexpect.TIMEOUT: traceback.print_tb(sys.exc_info()[2]) print("timed out") print(str(child)) sys.exit(2) except pexpect.EOF: print("EOF") print(str(child)) print(str(child.buffer)) print(str(child.before)) sys.exit(2) return child # Up and down arrows. # @param exe The executable. # @param args The arguments to pass to the executable. # @param env The environment. def test_bc4(exe, args, env): child = pexpect.spawn(exe, args=args, env=env) try: bc_banner(child) send(child, "\x1b[A\x1bOA\x1b[B\x1bOB") send(child, "\n") expect(child, prompt) write_str(child, "15") check_line(child, "15") write_str(child, "2^16") check_line(child, "65536") send(child, "\x1b[A\x1bOA") send(child, "\n") check_line(child, "15") send(child, "\x1b[A\x1bOA\x1b[A\x1b[B") check_line(child, "65536") send(child, "\x1b[A\x1bOA\x0e\x1b[A\x1b[A\x1b[A\x1b[B\x10\x1b[B\x1b[B\x1bOB\x1b[B\x1bOA") send(child, "\n") check_line(child, "65536") send(child, "quit") send(child, "\n") wait(child) except pexpect.TIMEOUT: traceback.print_tb(sys.exc_info()[2]) print("timed out") print(str(child)) sys.exit(2) except pexpect.EOF: print("EOF") print(str(child)) print(str(child.buffer)) print(str(child.before)) sys.exit(2) return child # Clear screen. # @param exe The executable. # @param args The arguments to pass to the executable. # @param env The environment. def test_bc5(exe, args, env): child = pexpect.spawn(exe, args=args, env=env) try: bc_banner(child) send(child, "\x0c") send(child, "quit") send(child, "\n") wait(child) except pexpect.TIMEOUT: traceback.print_tb(sys.exc_info()[2]) print("timed out") print(str(child)) sys.exit(2) except pexpect.EOF: print("EOF") print(str(child)) print(str(child.buffer)) print(str(child.before)) sys.exit(2) return child # Printed material without a newline. # @param exe The executable. # @param args The arguments to pass to the executable. # @param env The environment. def test_bc6(exe, args, env): child = pexpect.spawn(exe, args=args, env=env) try: bc_banner(child) send(child, "print \"Enter number: \"") send(child, "\n") expect(child, "Enter number: ") send(child, "4\x1b[A\x1b[A") send(child, "\n") send(child, "quit") send(child, "\n") wait(child) except pexpect.TIMEOUT: traceback.print_tb(sys.exc_info()[2]) print("timed out") print(str(child)) sys.exit(2) except pexpect.EOF: print("EOF") print(str(child)) print(str(child.buffer)) print(str(child.before)) sys.exit(2) return child # Word start and word end. # @param exe The executable. # @param args The arguments to pass to the executable. # @param env The environment. def test_bc7(exe, args, env): child = pexpect.spawn(exe, args=args, env=env) try: bc_banner(child) send(child, "\x1bb\x1bb\x1bf\x1bf") send(child, "\n") expect(child, prompt) send(child, "\x1b[0~\x1b[3a") send(child, "\n") expect(child, prompt) send(child, "\x1b[0;4\x1b[0A") send(child, "\n") expect(child, prompt) send(child, " ") send(child, "\x1bb\x1bb\x1bb\x1bb\x1bb\x1bb\x1bb\x1bb\x1bb\x1bb\x1bb\x1bb") send(child, "\x1bf\x1bf\x1bf\x1bf\x1bf\x1bf\x1bf\x1bf\x1bf\x1bf\x1bf\x1bf") send(child, "\n") expect(child, prompt) write_str(child, "12 + 34 + 56 + 78 + 90") check_line(child, "270") send(child, "\x1b[A") send(child, "\x1bb\x1bb\x1bb\x1bb\x1bb\x1bb\x1bb\x1bb\x1bb\x1bb\x1bb") send(child, "\x1bf\x1bf\x1bf\x1bf\x1bf\x1bf\x1bf\x1bf\x1bf\x1bf\x1bf") check_line(child, "270") send(child, "\x1b[A") send(child, "\x1bh\x1bh\x1bf + 14 ") send(child, "\n") check_line(child, "284") send(child, "quit") send(child, "\n") wait(child) except pexpect.TIMEOUT: traceback.print_tb(sys.exc_info()[2]) print("timed out") print(str(child)) sys.exit(2) except pexpect.EOF: print("EOF") print(str(child)) print(str(child.buffer)) print(str(child.before)) sys.exit(2) return child # Backspace. # @param exe The executable. # @param args The arguments to pass to the executable. # @param env The environment. def test_bc8(exe, args, env): child = pexpect.spawn(exe, args=args, env=env) try: bc_banner(child) send(child, "12\x1b[D3\x1b[C4\x08\x7f") send(child, "\n") check_line(child, "13") send(child, "quit") send(child, "\n") wait(child) except pexpect.TIMEOUT: traceback.print_tb(sys.exc_info()[2]) print("timed out") print(str(child)) sys.exit(2) except pexpect.EOF: print("EOF") print(str(child)) print(str(child.buffer)) print(str(child.before)) sys.exit(2) return child # Backspace and delete words. # @param exe The executable. # @param args The arguments to pass to the executable. # @param env The environment. def test_bc9(exe, args, env): child = pexpect.spawn(exe, args=args, env=env) try: bc_banner(child) send(child, "\x1b[0;5D\x1b[0;5D\x1b[0;5D\x1b[0;5C\x1b[0;5D\x1bd\x1b[3~\x1b[d\x1b[d\x1b[d\x1b[d\x7f\x7f\x7f") send(child, "\n") expect(child, prompt) write_str(child, "12 + 34 + 56 + 78 + 90") check_line(child, "270") send(child, "\x1b[A") send(child, "\x1b[0;5D\x1b[0;5D\x1b[0;5D\x1b[0;5C\x1b[0;5D\x1bd\x1b[3~\x1b[d\x1b[d\x1b[d\x1b[d\x7f\x7f\x7f") send(child, "\n") check_line(child, "102") send(child, "\x1b[A") send(child, "\x17\x17") send(child, "\n") check_line(child, "46") send(child, "\x17\x17") send(child, "\n") expect(child, prompt) send(child, "quit") send(child, "\n") wait(child) except pexpect.TIMEOUT: traceback.print_tb(sys.exc_info()[2]) print("timed out") print(str(child)) sys.exit(2) except pexpect.EOF: print("EOF") print(str(child)) print(str(child.buffer)) print(str(child.before)) sys.exit(2) return child # Backspace and delete words 2. # @param exe The executable. # @param args The arguments to pass to the executable. # @param env The environment. def test_bc10(exe, args, env): child = pexpect.spawn(exe, args=args, env=env) try: bc_banner(child) send(child, "\x1b[3~\x1b[3~") send(child, "\n") expect(child, prompt) send(child, " \x1b[3~\x1b[3~") send(child, "\n") expect(child, prompt) write_str(child, "12 + 34 + 56 + 78 + 90") check_line(child, "270") send(child, "\x1b[A\x1b[A\x1b[A\x1b[B\x1b[B\x1b[B\x1b[A") send(child, "\n") check_line(child, "270") send(child, "\x1b[A\x1b[0;5D\x1b[0;5D\x0b") send(child, "\n") check_line(child, "180") send(child, "\x1b[A\x1521") check_line(child, "21") send(child, "quit") send(child, "\n") wait(child) except pexpect.TIMEOUT: traceback.print_tb(sys.exc_info()[2]) print("timed out") print(str(child)) sys.exit(2) except pexpect.EOF: print("EOF") print(str(child)) print(str(child.buffer)) print(str(child.before)) sys.exit(2) return child # Swap. # @param exe The executable. # @param args The arguments to pass to the executable. # @param env The environment. def test_bc11(exe, args, env): child = pexpect.spawn(exe, args=args, env=env) try: bc_banner(child) send(child, "\x1b[A\x02\x14") send(child, "\n") expect(child, prompt) write_str(child, "12 + 34 + 56 + 78") check_line(child, "180") send(child, "\x1b[A\x02\x14") check_line(child, "189") send(child, "quit") send(child, "\n") wait(child) except pexpect.TIMEOUT: traceback.print_tb(sys.exc_info()[2]) print("timed out") print(str(child)) sys.exit(2) except pexpect.EOF: print("EOF") print(str(child)) print(str(child.buffer)) print(str(child.before)) sys.exit(2) return child # Non-fatal error. # @param exe The executable. # @param args The arguments to pass to the executable. # @param env The environment. def test_bc12(exe, args, env): child = pexpect.spawn(exe, args=args, env=env) try: bc_banner(child) send(child, "12 +") send(child, "\n") time.sleep(1) if not child.isalive(): print("child exited early") print(str(child)) print(str(child.buffer)) sys.exit(1) send(child, "quit") send(child, "\n") wait(child) except pexpect.TIMEOUT: traceback.print_tb(sys.exc_info()[2]) print("timed out") print(str(child)) sys.exit(2) except pexpect.EOF: print("EOF") print(str(child)) print(str(child.buffer)) print(str(child.before)) sys.exit(2) return child def test_dc_utf8_0(exe, args, env): return test_utf8_0(exe, args, env, False) def test_dc_utf8_1(exe, args, env): return test_utf8_1(exe, args, env, False) def test_dc_utf8_2(exe, args, env): return test_utf8_2(exe, args, env, False) def test_dc_utf8_3(exe, args, env): return test_utf8_3(exe, args, env, False) def test_dc_utf8_4(exe, args, env): return test_utf8_4(exe, args, env, False) # Basic dc test. # @param exe The executable. # @param args The arguments to pass to the executable. # @param env The environment. def test_dc1(exe, args, env): child = pexpect.spawn(exe, args=args, env=env) try: write_str(child, "1pR") check_line(child, "1") write_str(child, "1pR") check_line(child, "1") write_str(child, "q") send(child, "\n") wait(child) except pexpect.TIMEOUT: traceback.print_tb(sys.exc_info()[2]) print("timed out") print(str(child)) sys.exit(2) except pexpect.EOF: print("EOF") print(str(child)) print(str(child.buffer)) print(str(child.before)) sys.exit(2) return child # SIGINT with quit. # @param exe The executable. # @param args The arguments to pass to the executable. # @param env The environment. def test_dc2(exe, args, env): env["TERM"] = "dumb" child = pexpect.spawn(exe, args=args, env=env) try: child.sendline("1pR") check_line(child, "1", history=False) time.sleep(1) child.sendintr() child.sendline("q") wait(child) except pexpect.TIMEOUT: traceback.print_tb(sys.exc_info()[2]) print("timed out") print(str(child)) sys.exit(2) except pexpect.EOF: print("EOF") print(str(child)) print(str(child.buffer)) print(str(child.before)) sys.exit(2) return child # Execute string. # @param exe The executable. # @param args The arguments to pass to the executable. # @param env The environment. def test_dc3(exe, args, env): child = pexpect.spawn(exe, args=args, env=env) try: write_str(child, "[1 15+pR]x") check_line(child, "16") write_str(child, "1pR") check_line(child, "1") write_str(child, "q") send(child, "\n") wait(child) except pexpect.TIMEOUT: traceback.print_tb(sys.exc_info()[2]) print("timed out") print(str(child)) sys.exit(2) except pexpect.EOF: print("EOF") print(str(child)) print(str(child.buffer)) print(str(child.before)) sys.exit(2) return child # The array of bc tests. bc_tests = [ test_bc_utf8_0, test_bc_utf8_1, test_bc_utf8_2, test_bc_utf8_3, test_bc_utf8_4, test_sigint_sigquit, test_eof, test_sigint, test_sigtstp, test_sigstop, test_bc1, test_bc2, test_bc3, test_bc4, test_bc5, test_bc6, test_bc7, test_bc8, test_bc9, test_bc10, test_bc11, test_bc12, ] # The array of dc tests. dc_tests = [ test_dc_utf8_0, test_dc_utf8_1, test_dc_utf8_2, test_dc_utf8_3, + test_dc_utf8_4, test_sigint_sigquit, test_eof, test_sigint, test_dc1, test_dc2, test_dc3, ] # Print the usage and exit with an error. def usage(): print("usage: {} [-t] dir [-a] test_idx [exe options...]".format(script)) print(" The valid values for dir are: 'bc' and 'dc'.") print(" The max test_idx for bc is {}.".format(len(bc_tests) - 1)) print(" The max test_idx for dc is {}.".format(len(dc_tests) - 1)) print(" If -a is given, the number of tests for dir is printed.") print(" No tests are run.") sys.exit(1) # Must run this script alone. if __name__ != "__main__": usage() if len(sys.argv) < 2: usage() idx = 1 exedir = sys.argv[idx] idx += 1 if exedir == "-t": do_test = True exedir = sys.argv[idx] idx += 1 else: do_test = False test_idx = sys.argv[idx] idx += 1 if test_idx == "-a": if exedir == "bc": l = len(bc_tests) else: l = len(dc_tests) print("{}".format(l)) sys.exit(0) test_idx = int(test_idx) # Set a default executable unless we have one. if len(sys.argv) >= idx + 1: exe = sys.argv[idx] else: exe = testdir + "/../bin/" + exedir exebase = os.path.basename(exe) # Use the correct options. if exebase == "bc": halt = "halt\n" options = "-l" test_array = bc_tests else: halt = "q\n" options = "-x" test_array = dc_tests # More command-line processing. if len(sys.argv) > idx + 1: exe = [ exe, sys.argv[idx + 1:], options ] else: exe = [ exe, options ] # This is the environment necessary for most tests. env = { "BC_BANNER": "1", "BC_PROMPT": "1", "DC_PROMPT": "1", "BC_TTY_MODE": "1", "DC_TTY_MODE": "1", "BC_SIGINT_RESET": "1", "DC_SIGINT_RESET": "1", } # Make sure to include the outside environment. env.update(os.environ) env.pop("BC_ENV_ARGS", None) env.pop("BC_LINE_LENGTH", None) env.pop("DC_ENV_ARGS", None) env.pop("DC_LINE_LENGTH", None) # Run the correct test. child = test_array[test_idx](exe[0], exe[1:], env) child.close() exit = child.exitstatus if exit is not None and exit != 0: print("child failed; expected exit code 0, got {}".format(exit)) print(str(child)) sys.exit(1) diff --git a/contrib/bc/tests/history.sh b/contrib/bc/tests/history.sh index 92db985a4f86..1898ae5499dc 100755 --- a/contrib/bc/tests/history.sh +++ b/contrib/bc/tests/history.sh @@ -1,110 +1,110 @@ #! /bin/sh # # SPDX-License-Identifier: BSD-2-Clause # # Copyright (c) 2018-2021 Gavin D. Howard and contributors. # # Redistribution and use in source and binary forms, with or without # modification, are permitted provided that the following conditions are met: # # * Redistributions of source code must retain the above copyright notice, this # list of conditions and the following disclaimer. # # * Redistributions in binary form must reproduce the above copyright notice, # this list of conditions and the following disclaimer in the documentation # and/or other materials provided with the distribution. # # THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS" # AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE # IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE # ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR CONTRIBUTORS BE # LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR # CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF # SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS # INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN # CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) # ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE # POSSIBILITY OF SUCH DAMAGE. # script="$0" testdir=$(dirname "$script") . "$testdir/../scripts/functions.sh" # usage: history.sh dir -a|idx [exe args...] # If Python does not exist, then just skip. py=$(command -v python3) err=$? if [ "$err" -ne 0 ]; then py=$(command -v python) err=$? if [ "$err" -ne 0 ]; then printf 'Could not find Python 3.\n' printf 'Skipping %s history tests...\n' "$d" exit 0 fi fi # d is "bc" or "dc" d="$1" shift # idx is either an index of the test to run or "-a". If it is "-a", then all # tests are run. idx="$1" shift if [ "$#" -gt 0 ]; then # exe is the executable to run. exe="$1" shift else exe="$testdir/../bin/$d" fi if [ "$d" = "bc" ]; then flip="! %s" addone="%s + 1" else flip="%s Np" addone="%s 1+p" fi # Set the test range correctly for all tests or one test. st is the start index. if [ "$idx" = "-a" ]; then idx=$("$py" "$testdir/history.py" "$d" -a) idx=$(printf '%s - 1\n' "$idx" | bc) st=0 else st="$idx" fi # Run all of the tests. for i in $(seq "$st" "$idx"); do printf 'Running %s history test %d...' "$d" "$i" - for j in $(seq 1 3); do + for j in $(seq 1 5); do "$py" "$testdir/history.py" "$d" "$i" "$exe" "$@" err="$?" if [ "$err" -eq 0 ]; then break fi done checktest_retcode "$d" "$err" "$d history test $i" printf 'pass\n' done diff --git a/contrib/bc/vs/bc.vcxproj b/contrib/bc/vs/bc.vcxproj index 19b53d66a405..6cfd7d489927 100644 --- a/contrib/bc/vs/bc.vcxproj +++ b/contrib/bc/vs/bc.vcxproj @@ -1,297 +1,297 @@ Debug Win32 Release Win32 Debug x64 Release x64 16.0 Win32Proj {4450d61f-2535-4085-b1b1-f96acd23cc9f} bc 10.0 Application true v142 Unicode Application false v142 true Unicode Application true v142 Unicode Application false v142 true Unicode true ClCompile false bin\$(Platform)\$(Configuration)\ bin\$(Platform)\$(Configuration)\ false ClCompile false bin\$(Platform)\$(Configuration)\ bin\$(Platform)\$(Configuration)\ true ClCompile false bin\$(Platform)\$(Configuration)\ bin\$(Platform)\$(Configuration)\ false ClCompile false bin\$(Platform)\$(Configuration)\ bin\$(Platform)\$(Configuration)\ Level3 true - BC_ENABLED=1;DC_ENABLED=1;BC_ENABLE_EXTRA_MATH=1;BC_ENABLE_HISTORY=0;BC_ENABLE_NLS=0;BC_DEBUG_CODE=0;BC_ENABLE_LIBRARY=0;BUILD_TYPE=HN;BC_DEFAULT_BANNER=1;BC_DEFAULT_SIGINT_RESET=0;DC_DEFAULT_SIGINT_RESET=0;BC_DEFAULT_TTY_MODE=1;DC_DEFAULT_TTY_MODE=1;BC_DEFAULT_PROMPT=1;DC_DEFAULT_PROMPT=1;WIN32;_DEBUG;_CONSOLE;%(PreprocessorDefinitions) + BC_ENABLED=1;DC_ENABLED=1;BC_ENABLE_EXTRA_MATH=1;BC_ENABLE_HISTORY=0;BC_ENABLE_NLS=0;BC_DEBUG_CODE=0;BC_ENABLE_LIBRARY=0;BUILD_TYPE=HN;BC_DEFAULT_BANNER=1;BC_DEFAULT_SIGINT_RESET=0;DC_DEFAULT_SIGINT_RESET=0;BC_DEFAULT_TTY_MODE=1;DC_DEFAULT_TTY_MODE=1;BC_DEFAULT_PROMPT=1;DC_DEFAULT_PROMPT=1;BC_DEFAULT_EXPR_EXIT=1;DC_DEFAULT_EXPR_EXIT=1;WIN32;_DEBUG;_CONSOLE;%(PreprocessorDefinitions) ..\include MultiThreadedDebug true Console true bcrypt.lib;%(AdditionalDependencies) copy /b /y $(OutDir)bc.exe $(OutDir)dc.exe Level3 true true true - BC_ENABLED=1;DC_ENABLED=1;BC_ENABLE_EXTRA_MATH=1;BC_ENABLE_HISTORY=0;BC_ENABLE_NLS=0;BC_DEBUG_CODE=0;BC_ENABLE_LIBRARY=0;BUILD_TYPE=HN;BC_DEFAULT_BANNER=1;BC_DEFAULT_SIGINT_RESET=0;DC_DEFAULT_SIGINT_RESET=0;BC_DEFAULT_TTY_MODE=1;DC_DEFAULT_TTY_MODE=1;BC_DEFAULT_PROMPT=1;DC_DEFAULT_PROMPT=1;WIN32;NDEBUG;_CONSOLE;%(PreprocessorDefinitions) + BC_ENABLED=1;DC_ENABLED=1;BC_ENABLE_EXTRA_MATH=1;BC_ENABLE_HISTORY=0;BC_ENABLE_NLS=0;BC_DEBUG_CODE=0;BC_ENABLE_LIBRARY=0;BUILD_TYPE=HN;BC_DEFAULT_BANNER=1;BC_DEFAULT_SIGINT_RESET=0;DC_DEFAULT_SIGINT_RESET=0;BC_DEFAULT_TTY_MODE=1;DC_DEFAULT_TTY_MODE=1;BC_DEFAULT_PROMPT=1;DC_DEFAULT_PROMPT=1;BC_DEFAULT_EXPR_EXIT=1;DC_DEFAULT_EXPR_EXIT=1;WIN32;NDEBUG;_CONSOLE;%(PreprocessorDefinitions) ..\include MultiThreaded true Console true true false bcrypt.lib;%(AdditionalDependencies) copy /b /y $(OutDir)bc.exe $(OutDir)dc.exe Level3 true - BC_ENABLED=1;DC_ENABLED=1;BC_ENABLE_EXTRA_MATH=1;BC_ENABLE_HISTORY=0;BC_ENABLE_NLS=0;BC_DEBUG_CODE=0;BC_ENABLE_LIBRARY=0;BUILD_TYPE=HN;BC_DEFAULT_BANNER=1;BC_DEFAULT_SIGINT_RESET=0;DC_DEFAULT_SIGINT_RESET=0;BC_DEFAULT_TTY_MODE=1;DC_DEFAULT_TTY_MODE=1;BC_DEFAULT_PROMPT=1;DC_DEFAULT_PROMPT=1;_DEBUG;_CONSOLE;%(PreprocessorDefinitions) + BC_ENABLED=1;DC_ENABLED=1;BC_ENABLE_EXTRA_MATH=1;BC_ENABLE_HISTORY=0;BC_ENABLE_NLS=0;BC_DEBUG_CODE=0;BC_ENABLE_LIBRARY=0;BUILD_TYPE=HN;BC_DEFAULT_BANNER=1;BC_DEFAULT_SIGINT_RESET=0;DC_DEFAULT_SIGINT_RESET=0;BC_DEFAULT_TTY_MODE=1;DC_DEFAULT_TTY_MODE=1;BC_DEFAULT_PROMPT=1;DC_DEFAULT_PROMPT=1;BC_DEFAULT_EXPR_EXIT=1;DC_DEFAULT_EXPR_EXIT=1;_DEBUG;_CONSOLE;%(PreprocessorDefinitions) ..\include MultiThreadedDebug true Console true bcrypt.lib;%(AdditionalDependencies) copy /b /y $(OutDir)bc.exe $(OutDir)dc.exe Level3 true true - BC_ENABLED=1;DC_ENABLED=1;BC_ENABLE_EXTRA_MATH=1;BC_ENABLE_HISTORY=0;BC_ENABLE_NLS=0;BC_DEBUG_CODE=0;BC_ENABLE_LIBRARY=0;BUILD_TYPE=HN;BC_DEFAULT_BANNER=1;BC_DEFAULT_SIGINT_RESET=0;DC_DEFAULT_SIGINT_RESET=0;BC_DEFAULT_TTY_MODE=1;DC_DEFAULT_TTY_MODE=1;BC_DEFAULT_PROMPT=1;DC_DEFAULT_PROMPT=1;NDEBUG;_CONSOLE;%(PreprocessorDefinitions) + BC_ENABLED=1;DC_ENABLED=1;BC_ENABLE_EXTRA_MATH=1;BC_ENABLE_HISTORY=0;BC_ENABLE_NLS=0;BC_DEBUG_CODE=0;BC_ENABLE_LIBRARY=0;BUILD_TYPE=HN;BC_DEFAULT_BANNER=1;BC_DEFAULT_SIGINT_RESET=0;DC_DEFAULT_SIGINT_RESET=0;BC_DEFAULT_TTY_MODE=1;DC_DEFAULT_TTY_MODE=1;BC_DEFAULT_PROMPT=1;DC_DEFAULT_PROMPT=1;BC_DEFAULT_EXPR_EXIT=1;DC_DEFAULT_EXPR_EXIT=1;NDEBUG;_CONSOLE;%(PreprocessorDefinitions) ..\include MultiThreaded true true Console true true false bcrypt.lib;%(AdditionalDependencies) copy /b /y $(OutDir)bc.exe $(OutDir)dc.exe CppCode cl.exe /Fo:$(OutDir)strgen.obj /Fe:$(OutDir)strgen.exe %(Identity) $(OutDir)strgen.exe cl.exe /Fo:$(OutDir)strgen.obj /Fe:$(OutDir)strgen.exe %(Identity) $(OutDir)strgen.exe cl.exe /Fo:$(OutDir)strgen.obj /Fe:$(OutDir)strgen.exe %(Identity) $(OutDir)strgen.exe cl.exe /Fo:$(OutDir)strgen.obj /Fe:$(OutDir)strgen.exe %(Identity) $(OutDir)strgen.exe Document $(OutDir)strgen.exe %(Identity) src2\lib.c bc_lib bc_lib_name BC_ENABLED 1 src2\lib.c $(OutDir)strgen.exe %(Identity) src2\lib.c bc_lib bc_lib_name BC_ENABLED 1 src2\lib.c $(OutDir)strgen.exe %(Identity) src2\lib.c bc_lib bc_lib_name BC_ENABLED 1 src2\lib.c $(OutDir)strgen.exe %(Identity) src2\lib.c bc_lib bc_lib_name BC_ENABLED 1 src2\lib.c Document $(OutDir)strgen.exe %(Identity) src2\lib2.c bc_lib2 bc_lib2_name BC_ENABLED 1 src2\lib2.c $(OutDir)strgen.exe %(Identity) src2\lib2.c bc_lib2 bc_lib2_name BC_ENABLED 1 src2\lib2.c $(OutDir)strgen.exe %(Identity) src2\lib2.c bc_lib2 bc_lib2_name BC_ENABLED 1 src2\lib2.c $(OutDir)strgen.exe %(Identity) src2\lib2.c bc_lib2 bc_lib2_name BC_ENABLED 1 src2\lib2.c $(OutDir)strgen.exe %(Identity) src2\dc_help.c dc_help "" DC_ENABLED src2\dc_help.c $(OutDir)strgen.exe %(Identity) src2\dc_help.c dc_help "" DC_ENABLED src2\dc_help.c $(OutDir)strgen.exe %(Identity) src2\dc_help.c dc_help "" DC_ENABLED src2\dc_help.c $(OutDir)strgen.exe %(Identity) src2\dc_help.c dc_help "" DC_ENABLED src2\dc_help.c $(OutDir)strgen.exe %(Identity) src2\bc_help.c bc_help "" BC_ENABLED src2\bc_help.c $(OutDir)strgen.exe %(Identity) src2\bc_help.c bc_help "" BC_ENABLED src2\bc_help.c $(OutDir)strgen.exe %(Identity) src2\bc_help.c bc_help "" BC_ENABLED src2\bc_help.c $(OutDir)strgen.exe %(Identity) src2\bc_help.c bc_help "" BC_ENABLED src2\bc_help.c \ No newline at end of file