diff --git a/usr.bin/wc/wc.c b/usr.bin/wc/wc.c
--- a/usr.bin/wc/wc.c
+++ b/usr.bin/wc/wc.c
@@ -50,10 +50,10 @@
 
 #include <capsicum_helpers.h>
 #include <ctype.h>
-#include <err.h>
 #include <errno.h>
 #include <fcntl.h>
 #include <locale.h>
+#include <stdbool.h>
 #include <stdint.h>
 #include <stdio.h>
 #include <stdlib.h>
@@ -66,9 +66,11 @@
 #include <libcasper.h>
 #include <casper/cap_fileargs.h>
 
+static const char *stdin_filename = "stdin";
+
 static fileargs_t *fa;
 static uintmax_t tlinect, twordct, tcharct, tlongline;
-static int doline, doword, dochar, domulti, dolongline;
+static bool doline, doword, dochar, domulti, dolongline;
 static volatile sig_atomic_t siginfo;
 static xo_handle_t *stderr_handle;
 
@@ -107,21 +109,21 @@
 	while ((ch = getopt(argc, argv, "clmwL")) != -1)
 		switch((char)ch) {
 		case 'l':
-			doline = 1;
+			doline = true;
 			break;
 		case 'w':
-			doword = 1;
+			doword = true;
 			break;
 		case 'c':
-			dochar = 1;
-			domulti = 0;
+			dochar = true;
+			domulti = false;
 			break;
 		case 'L':
-			dolongline = 1;
+			dolongline = true;
 			break;
 		case 'm':
-			domulti = 1;
-			dochar = 0;
+			domulti = true;
+			dochar = false;
 			break;
 		case '?':
 		default:
@@ -162,19 +164,19 @@
 
 	errors = 0;
 	total = 0;
-	if (!*argv) {
-	 	xo_open_instance("file");
-		if (cnt((char *)NULL) != 0)
+	if (argc == 0) {
+		xo_open_instance("file");
+		if (cnt(NULL) != 0)
 			++errors;
-	 	xo_close_instance("file");
+		xo_close_instance("file");
 	} else {
-		do {
-	 		xo_open_instance("file");
-			if (cnt(*argv) != 0)
+		while (argc--) {
+			xo_open_instance("file");
+			if (cnt(*argv++) != 0)
 				++errors;
-	 		xo_close_instance("file");
+			xo_close_instance("file");
 			++total;
-		} while(*++argv);
+		}
 	}
 
 	xo_close_list("file");
@@ -187,7 +189,8 @@
 
 	fileargs_free(fa);
 	xo_close_container("wc");
-	xo_finish();
+	if (xo_finish() < 0)
+		xo_err(1, "stdout");
 	exit(errors == 0 ? 0 : 1);
 }
 
@@ -212,7 +215,7 @@
 		xo_emit_h(xop, " {:characters/%7ju/%ju}", charct);
 	if (dolongline)
 		xo_emit_h(xop, " {:long-lines/%7ju/%ju}", llct);
-	if (file != NULL)
+	if (file != stdin_filename)
 		xo_emit_h(xop, " {:filename/%s}\n", file);
 	else
 		xo_emit_h(xop, "\n");
@@ -221,20 +224,21 @@
 static int
 cnt(const char *file)
 {
+	char buf[MAXBSIZE], *p;
 	struct stat sb;
+	mbstate_t mbs;
 	uintmax_t linect, wordct, charct, llct, tmpll;
-	int fd, len, warned;
+	ssize_t len;
 	size_t clen;
-	short gotsp;
-	u_char *p;
-	u_char buf[MAXBSIZE];
+	int fd;
 	wchar_t wch;
-	mbstate_t mbs;
+	bool gotsp, warned;
 
 	linect = wordct = charct = llct = tmpll = 0;
-	if (file == NULL)
+	if (file == NULL) {
 		fd = STDIN_FILENO;
-	else if ((fd = fileargs_open(fa, file)) < 0) {
+		file = stdin_filename;
+	} else if ((fd = fileargs_open(fa, file)) < 0) {
 		xo_warn("%s: open", file);
 		return (1);
 	}
@@ -246,7 +250,7 @@
 	 */
 	if (doline == 0 && dolongline == 0) {
 		if (fstat(fd, &sb)) {
-			xo_warn("%s: fstat", file != NULL ? file : "stdin");
+			xo_warn("%s: fstat", file);
 			(void)close(fd);
 			return (1);
 		}
@@ -266,8 +270,8 @@
 	 * handling.
 	 */
 	while ((len = read(fd, buf, MAXBSIZE))) {
-		if (len == -1) {
-			xo_warn("%s: read", file != NULL ? file : "stdin");
+		if (len < 0) {
+			xo_warn("%s: read", file);
 			(void)close(fd);
 			return (1);
 		}
@@ -275,14 +279,16 @@
 			show_cnt(file, linect, wordct, charct, llct);
 		charct += len;
 		if (doline || dolongline) {
-			for (p = buf; len--; ++p)
+			for (p = buf; len > 0; --len, ++p) {
 				if (*p == '\n') {
 					if (tmpll > llct)
 						llct = tmpll;
 					tmpll = 0;
 					++linect;
-				} else
+				} else {
 					tmpll++;
+				}
+			}
 		}
 	}
 	reset_siginfo();
@@ -297,12 +303,12 @@
 	return (0);
 
 	/* Do it the hard way... */
-word:	gotsp = 1;
-	warned = 0;
+word:	gotsp = true;
+	warned = false;
 	memset(&mbs, 0, sizeof(mbs));
 	while ((len = read(fd, buf, MAXBSIZE)) != 0) {
-		if (len == -1) {
-			xo_warn("%s: read", file != NULL ? file : "stdin");
+		if (len < 0) {
+			xo_warn("%s: read", file);
 			(void)close(fd);
 			return (1);
 		}
@@ -313,21 +319,20 @@
 			if (!domulti || MB_CUR_MAX == 1) {
 				clen = 1;
 				wch = (unsigned char)*p;
-			} else if ((clen = mbrtowc(&wch, p, len, &mbs)) ==
-			    (size_t)-1) {
+			} else if ((clen = mbrtowc(&wch, p, len, &mbs)) == 0) {
+				clen = 1;
+			} else if (clen == (size_t)-1) {
 				if (!warned) {
 					errno = EILSEQ;
-					xo_warn("%s",
-					    file != NULL ? file : "stdin");
-					warned = 1;
+					xo_warn("%s", file);
+					warned = true;
 				}
 				memset(&mbs, 0, sizeof(mbs));
 				clen = 1;
 				wch = (unsigned char)*p;
-			} else if (clen == (size_t)-2)
+			} else if (clen == (size_t)-2) {
 				break;
-			else if (clen == 0)
-				clen = 1;
+			}
 			charct++;
 			if (wch != L'\n')
 				tmpll++;
@@ -339,18 +344,19 @@
 				tmpll = 0;
 				++linect;
 			}
-			if (iswspace(wch))
-				gotsp = 1;
-			else if (gotsp) {
-				gotsp = 0;
+			if (iswspace(wch)) {
+				gotsp = true;
+			} else if (gotsp) {
+				gotsp = false;
 				++wordct;
 			}
 		}
 	}
 	reset_siginfo();
-	if (domulti && MB_CUR_MAX > 1)
+	if (domulti && MB_CUR_MAX > 1) {
 		if (mbrtowc(NULL, NULL, 0, &mbs) == (size_t)-1 && !warned)
-			xo_warn("%s", file != NULL ? file : "stdin");
+			xo_warn("%s", file);
+	}
 	if (doline)
 		tlinect += linect;
 	if (doword)