diff --git a/usr.bin/diff/diff.1 b/usr.bin/diff/diff.1
index 6351c58114e0..29ee32cb8d2b 100644
--- a/usr.bin/diff/diff.1
+++ b/usr.bin/diff/diff.1
@@ -1,750 +1,759 @@
 .\" $OpenBSD: diff.1,v 1.47 2015/11/24 19:35:41 jmc Exp $
 .\"
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 .Dd February 26, 2024
 .Dt DIFF 1
 .Os
 .Sh NAME
 .Nm diff
 .Nd differential file and directory comparator
 .Sh SYNOPSIS
 .Nm diff
 .Op Fl aBbdipTtw
 .Oo
 .Fl c | e | f |
 .Fl n | q | u | y
 .Oc
 .Op Fl -brief
 .Op Fl -color Ns = Ns Ar when
 .Op Fl -changed-group-format Ar GFMT
 .Op Fl -ed
 .Op Fl -expand-tabs
 .Op Fl -forward-ed
 .Op Fl -ignore-all-space
 .Op Fl -ignore-case
 .Op Fl -ignore-space-change
 .Op Fl -initial-tab
 .Op Fl -minimal
 .Op Fl -no-ignore-file-name-case
 .Op Fl -normal
 .Op Fl -rcs
 .Op Fl -show-c-function
 .Op Fl -starting-file
 .Op Fl -speed-large-files
 .Op Fl -strip-trailing-cr
 .Op Fl -tabsize Ar number
 .Op Fl -text
 .Op Fl -unified
 .Op Fl I Ar pattern | Fl -ignore-matching-lines Ar pattern
 .Op Fl F Ar pattern | Fl -show-function-line Ar pattern
 .Op Fl L Ar label | Fl -label Ar label
 .Ar file1 file2
 .Nm diff
 .Op Fl aBbdilpTtw
 .Op Fl I Ar pattern | Fl -ignore-matching-lines Ar pattern
 .Op Fl F Ar pattern | Fl -show-function-line Ar pattern
 .Op Fl L Ar label | Fl -label Ar label
 .Op Fl -brief
 .Op Fl -color Ns = Ns Ar when
 .Op Fl -changed-group-format Ar GFMT
 .Op Fl -ed
 .Op Fl -expand-tabs
 .Op Fl -forward-ed
 .Op Fl -ignore-all-space
 .Op Fl -ignore-case
 .Op Fl -ignore-space-change
 .Op Fl -initial-tab
 .Op Fl -minimal
 .Op Fl -no-ignore-file-name-case
 .Op Fl -normal
 .Op Fl -paginate
 .Op Fl -rcs
 .Op Fl -show-c-function
 .Op Fl -speed-large-files
 .Op Fl -starting-file
 .Op Fl -strip-trailing-cr
 .Op Fl -tabsize Ar number
 .Op Fl -text
 .Fl C Ar number | -context Ar number
 .Ar file1 file2
 .Nm diff
 .Op Fl aBbdiltw
 .Op Fl I Ar pattern | Fl -ignore-matching-lines Ar pattern
 .Op Fl -brief
 .Op Fl -color Ns = Ns Ar when
 .Op Fl -changed-group-format Ar GFMT
 .Op Fl -ed
 .Op Fl -expand-tabs
 .Op Fl -forward-ed
 .Op Fl -ignore-all-space
 .Op Fl -ignore-case
 .Op Fl -ignore-space-change
 .Op Fl -initial-tab
 .Op Fl -minimal
 .Op Fl -no-ignore-file-name-case
 .Op Fl -normal
 .Op Fl -paginate
 .Op Fl -rcs
 .Op Fl -show-c-function
 .Op Fl -speed-large-files
 .Op Fl -starting-file
 .Op Fl -strip-trailing-cr
 .Op Fl -tabsize Ar number
 .Op Fl -text
 .Fl D Ar string | Fl -ifdef Ar string
 .Ar file1 file2
 .Nm diff
 .Op Fl aBbdilpTtw
 .Op Fl I Ar pattern | Fl -ignore-matching-lines Ar pattern
 .Op Fl F Ar pattern | Fl -show-function-line Ar pattern
 .Op Fl L Ar label | Fl -label Ar label
 .Op Fl -brief
 .Op Fl -color Ns = Ns Ar when
 .Op Fl -changed-group-format Ar GFMT
 .Op Fl -ed
 .Op Fl -expand-tabs
 .Op Fl -forward-ed
 .Op Fl -ignore-all-space
 .Op Fl -ignore-case
 .Op Fl -ignore-space-change
 .Op Fl -initial-tab
 .Op Fl -minimal
 .Op Fl -no-ignore-file-name-case
 .Op Fl -normal
 .Op Fl -paginate
 .Op Fl -rcs
 .Op Fl -show-c-function
 .Op Fl -speed-large-files
 .Op Fl -starting-file
 .Op Fl -strip-trailing-cr
 .Op Fl -tabsize Ar number
 .Op Fl -text
 .Fl U Ar number | Fl -unified Ar number
 .Ar file1 file2
 .Nm diff
 .Op Fl aBbdilNPprsTtw
 .Oo
 .Fl c | e | f |
 .Fl n | q | u
 .Oc
 .Op Fl -brief
 .Op Fl -color Ns = Ns Ar when
 .Op Fl -changed-group-format Ar GFMT
 .Op Fl -context
 .Op Fl -ed
 .Op Fl -expand-tabs
 .Op Fl -forward-ed
 .Op Fl -ignore-all-space
 .Op Fl -ignore-case
 .Op Fl -ignore-space-change
 .Op Fl -initial-tab
 .Op Fl -minimal
 .Op Fl -new-file
 .Op Fl -no-ignore-file-name-case
 .Op Fl -normal
 .Op Fl -paginate
 .Op Fl -rcs
 .Op Fl -recursive
 .Op Fl -report-identical-files
 .Op Fl -show-c-function
 .Op Fl -speed-large-files
 .Op Fl -strip-trailing-cr
 .Op Fl -tabsize Ar number
 .Op Fl -text
 .Op Fl -unidirectional-new-file
 .Op Fl -unified
 .Op Fl I Ar pattern | Fl -ignore-matching-lines Ar pattern
 .Op Fl F Ar pattern | Fl -show-function-line Ar pattern
 .Bk -words
 .Op Fl L Ar label | Fl -label Ar label
 .Op Fl S Ar name | Fl -starting-file Ar name
 .Op Fl X Ar file | Fl -exclude-from Ar file
 .Op Fl x Ar pattern | Fl -exclude Ar pattern
 .Ek
 .Ar dir1 dir2
 .Nm diff
 .Op Fl aBbditwW
 .Op Fl -color Ns = Ns Ar when
 .Op Fl -expand-tabs
 .Op Fl -ignore-all-blanks
 .Op Fl -ignore-blank-lines
 .Op Fl -ignore-case
 .Op Fl -minimal
 .Op Fl -no-ignore-file-name-case
 .Op Fl -strip-trailing-cr
 .Op Fl -suppress-common-lines
 .Op Fl -tabsize Ar number
 .Op Fl -text
 .Op Fl -width
 .Fl y | Fl -side-by-side
 .Ar file1 file2
 .Nm diff
 .Op Fl -help
 .Op Fl -version
 .Sh DESCRIPTION
 The
 .Nm
 utility compares the contents of
 .Ar file1
 and
 .Ar file2
 and writes to the standard output the list of changes necessary to
 convert one file into the other.
 No output is produced if the files are identical.
 .Pp
 Output options (mutually exclusive):
 .Bl -tag -width Ds
 .It Fl C Ar number Fl -context Ar number
 Like
 .Fl c
 but produces a diff with
 .Ar number
 lines of context.
 .It Fl c
 Produces a diff with 3 lines of context.
 With
 .Fl c
 the output format is modified slightly:
 the output begins with identification of the files involved and
 their creation dates and then each change is separated
 by a line with fifteen
 .Li * Ns 's .
 The lines removed from
 .Ar file1
 are marked with
 .Sq \&-\ \& ;
 those added to
 .Ar file2
 are marked
 .Sq +\ \& .
 Lines which are changed from one file to the other are marked in
 both files with
 .Sq !\ \& .
 Changes which lie within 3 lines of each other are grouped together on
 output.
 .It Fl D Ar string Fl -ifdef Ar string
 Creates a merged version of
 .Ar file1
 and
 .Ar file2
 on the standard output, with C preprocessor controls included so that
 a compilation of the result without defining
 .Ar string
 is equivalent to compiling
 .Ar file1 ,
 while defining
 .Ar string
 will yield
 .Ar file2 .
 .It Fl e -ed
 Produces output in a form suitable as input for the editor utility,
 .Xr ed 1 ,
 which can then be used to convert file1 into file2.
 .Pp
 Extra commands are added to the output when comparing directories with
 .Fl e ,
 so that the result is a
 .Xr sh 1
 script for converting text files which are common to the two directories
 from their state in
 .Ar dir1
 to their state in
 .Ar dir2 .
 .It Fl f -forward-ed
 Identical output to that of the
 .Fl e
 flag, but in reverse order.
 It cannot be digested by
 .Xr ed 1 .
 .It Fl -help
 This option prints a summary to stdout and exits with status 0.
 .It Fl n
 Produces a script similar to that of
 .Fl e ,
 but in the opposite order and with a count of changed lines on each
 insert or delete command.
 This is the form used by rcsdiff.
 .It Fl q -brief
 Just print a line when the files differ.
 Does not output a list of changes.
 .It Fl U Ar number Fl -unified Ar number
 Like
 .Fl u
 but produces a diff with
 .Ar number
 lines of context.
 .It Fl u
 Produces a
 .Em unified
 diff with 3 lines of context.
 A unified diff is similar to the context diff produced by the
 .Fl c
 option.
 However, unlike with
 .Fl c ,
 all lines to be changed (added and/or removed) are present in
 a single section.
 .It Fl -version
 This option prints a version string to stdout and exits with status 0.
 .It Fl y Fl -side-by-side
 Output in two columns with a marker between them.
 The marker can be one
 of the following:
 .Pp
 .Bl -tag -width Ds -offset indent -compact
 .It space
 Corresponding lines are identical.
 .It '|'
 Corresponding lines are different.
 .It '<'
 Files differ and only the first file contains the line.
 .It '>'
 Files differ and only the second file contains the line.
 .El
 .El
 .Pp
 Comparison options:
 .Bl -tag -width Ds
 .It Fl a -text
 Treat all files as ASCII text.
 Normally
 .Nm
 will simply print
 .Dq Binary files ... differ
 if files contain binary characters.
 Use of this option forces
 .Nm
 to produce a diff.
 .It Fl B Fl -ignore-blank-lines
 Causes chunks that include only blank lines to be ignored.
 .It Fl b -ignore-space-change
 Causes trailing blanks (spaces and tabs) to be ignored, and other
 strings of blanks to compare equal.
 .It Fl -color= Ns Oo Ar when Oc
 Color the additions green, and removals red, or the value in the
 .Ev DIFFCOLORS
 environment variable.
 The possible values of
 .Ar when
 are
 .Dq Cm never ,
 .Dq Cm always
 and
 .Dq Cm auto .
 .Cm auto
 will use color if the output is a tty and the
 .Ev COLORTERM
 environment variable is set to a non-empty string.
 .It Fl d -minimal
 Try very hard to produce a diff as small as possible.
 This may consume a lot of processing power and memory when processing
 large files with many changes.
 .It Fl F Ar pattern, Fl -show-function-line Ar pattern
 Like
 .Fl p,
 but display the last line that matches provided pattern.
 .It Fl I Ar pattern Fl -ignore-matching-lines Ar pattern
 Ignores changes, insertions, and deletions whose lines match the
 extended regular expression
 .Ar pattern .
 Multiple
 .Fl I
 patterns may be specified.
 All lines in the change must match some pattern for the change to be
 ignored.
 See
 .Xr re_format 7
 for more information on regular expression patterns.
 .It Fl i -ignore-case
 Ignores the case of letters.
 E.g.,
 .Dq A
 will compare equal to
 .Dq a .
 .It Fl l -paginate
 Pass the output through
 .Xr pr 1
 to paginate it.
 .It Fl L Ar label Fl -label Ar label
 Print
 .Ar label
 instead of the first (and second, if this option is specified twice)
 file name and time in the context or unified diff header.
 .It Fl p -show-c-function
 With unified and context diffs, show with each change
 the first 40 characters of the last line before the context beginning
 with a letter, an underscore or a dollar sign.
 For C and Objective-C source code following standard layout conventions, this
 will show the prototype of the function the change applies to.
 .It Fl T -initial-tab
 Print a tab rather than a space before the rest of the line for the
 normal, context or unified output formats.
 This makes the alignment of tabs in the line consistent.
 .It Fl t -expand-tabs
 Will expand tabs in output lines.
 Normal or
 .Fl c
 output adds character(s) to the front of each line which may screw up
 the indentation of the original source lines and make the output listing
 difficult to interpret.
 This option will preserve the original source's indentation.
 .It Fl w -ignore-all-blanks
 Is similar to
 .Fl b -ignore-space-change
 but causes whitespace (blanks and tabs) to be totally ignored.
 E.g.,
 .Dq if (\ \&a == b \&)
 will compare equal to
 .Dq if(a==b) .
 .It Fl W Ar number Fl -width Ar number
 Output at most
 .Ar number
 columns when using side by side format.
 The default value is 130.
 Note that unless
 .It Fl t
 was specified,
 .Nm
 will always align the second column to a tab stop, so values of
 .Fl -width
 smaller than approximately five times the value of
 .Fl -tabsize
 may yield surprising results.
 .It Fl -changed-group-format Ar GFMT
 Format input groups in the provided
 .Pp
 the format is a string with special keywords:
 .Bl -tag -width %<
 .It %<
 lines from FILE1
 .It %<
 lines from FILE2
 .El
 .It Fl -ignore-file-name-case
 ignore case when comparing file names
 .It Fl -no-ignore-file-name-case
 do not ignore case when comparing file names (default)
 .It Fl -normal
 default diff output
 .It Fl -speed-large-files
 stub option for compatibility with GNU diff
 .It Fl -strip-trailing-cr
 strip carriage return on input files
 .It Fl -suppress-common-lines
 Do not output common lines when using the side by side format
 .It Fl -tabsize Ar number
 Number of spaces representing a tab (default 8)
 .El
 .Pp
 Directory comparison options:
 .Bl -tag -width Ds
 .It Fl N -new-file
 If a file is found in only one directory, act as if it was found in the
 other directory too but was of zero size.
 .It Fl P -unidirectional-new-file
 If a file is found only in
 .Ar dir2 ,
 act as if it was found in
 .Ar dir1
 too but was of zero size.
 .It Fl r -recursive
 Causes application of
 .Nm
 recursively to common subdirectories encountered.
 .It Fl S Ar name Fl -starting-file Ar name
 Re-starts a directory
 .Nm
 in the middle, beginning with file
 .Ar name .
 .It Fl s -report-identical-files
 Causes
 .Nm
 to report files which are the same, which are otherwise not mentioned.
 .It Fl X Ar file Fl -exclude-from Ar file
 Exclude files and subdirectories from comparison whose basenames match
 lines in
 .Ar file .
 Multiple
 .Fl X
 options may be specified.
 .It Fl x Ar pattern Fl -exclude Ar pattern
 Exclude files and subdirectories from comparison whose basenames match
 .Ar pattern .
 Patterns are matched using shell-style globbing via
 .Xr fnmatch 3 .
 Multiple
 .Fl x
 options may be specified.
 .El
 .Pp
 If both arguments are directories,
 .Nm
 sorts the contents of the directories by name, and then runs the
 regular file
 .Nm
 algorithm, producing a change list,
 on text files which are different.
 Binary files which differ,
 common subdirectories, and files which appear in only one directory
 are described as such.
 In directory mode only regular files and directories are compared.
 If a non-regular file such as a device special file or FIFO is encountered,
 a diagnostic message is printed.
 .Pp
 If only one of
 .Ar file1
 and
 .Ar file2
 is a directory,
 .Nm
 is applied to the non-directory file and the file contained in
 the directory file with a filename that is the same as the
 last component of the non-directory file.
 .Pp
 If either
 .Ar file1
 or
 .Ar file2
 is
 .Sq - ,
 the standard input is
 used in its place.
 .Ss Output Style
 The default (without
 .Fl e ,
 .Fl c ,
 or
 .Fl n -rcs
 .\" -C
 options)
 output contains lines of these forms, where
 .Va XX , YY , ZZ , QQ
 are line numbers respective of file order.
 .Pp
 .Bl -tag -width "XX,YYcZZ,QQ" -compact
 .It Li XX Ns Ic a Ns Li YY
 At (the end of) line
 .Va XX
 of
 .Ar file1 ,
 append the contents
 of line
 .Va YY
 of
 .Ar file2
 to make them equal.
 .It Li XX Ns Ic a Ns Li YY,ZZ
 Same as above, but append the range of lines,
 .Va YY
 through
 .Va ZZ
 of
 .Ar file2
 to line
 .Va XX
 of file1.
 .It Li XX Ns Ic d Ns Li YY
 At line
 .Va XX
 delete
 the line.
 The value
 .Va YY
 tells to which line the change would bring
 .Ar file1
 in line with
 .Ar file2 .
 .It Li XX,YY Ns Ic d Ns Li ZZ
 Delete the range of lines
 .Va XX
 through
 .Va YY
 in
 .Ar file1 .
 .It Li XX Ns Ic c Ns Li YY
 Change the line
 .Va XX
 in
 .Ar file1
 to the line
 .Va YY
 in
 .Ar file2 .
 .It Li XX,YY Ns Ic c Ns Li ZZ
 Replace the range of specified lines with the line
 .Va ZZ .
 .It Li XX,YY Ns Ic c Ns Li ZZ,QQ
 Replace the range
 .Va XX , Ns Va YY
 from
 .Ar file1
 with the range
 .Va ZZ , Ns Va QQ
 from
 .Ar file2 .
 .El
 .Pp
 These lines resemble
 .Xr ed 1
 subcommands to convert
 .Ar file1
 into
 .Ar file2 .
 The line numbers before the action letters pertain to
 .Ar file1 ;
 those after pertain to
 .Ar file2 .
 Thus, by exchanging
 .Ic a
 for
 .Ic d
 and reading the line in reverse order, one can also
 determine how to convert
 .Ar file2
 into
 .Ar file1 .
 As in
 .Xr ed 1 ,
 identical
 pairs (where num1 = num2) are abbreviated as a single
 number.
 .Sh ENVIRONMENT
 .Bl -tag -width DIFFCOLORS
 .It Ev DIFFCOLORS
 The value of this variable is the form
 .Ar add Ns : Ns Ar rm ,
 where
 .Ar add
 is the ASCII escape sequence for additions and
 .Ar rm
 is the ASCII escape sequence for deletions.
 If this is unset,
 .Nm
 uses green for additions and red for removals.
 .El
 .Sh FILES
 .Bl -tag -width /tmp/diff.XXXXXXXX -compact
 .It Pa /tmp/diff.XXXXXXXX
 Temporary file used when comparing a device or the standard input.
 Note that the temporary file is unlinked as soon as it is created
 so it will not show up in a directory listing.
 .El
 .Sh EXIT STATUS
 The
 .Nm
 utility exits with one of the following values:
 .Pp
 .Bl -tag -width Ds -offset indent -compact
 .It 0
 No differences were found.
 .It 1
 Differences were found.
 .It >1
 An error occurred.
 .El
 .Pp
 The
 .Fl -help
 and
 .Fl -version
 options exit with a status of 0.
 .Sh EXAMPLES
 Compare
 .Pa old_dir
 and
 .Pa new_dir
 recursively generating an unified diff and treating files found only in one
 of those directories as new files:
 .Bd -literal -offset indent
 $ diff -ruN /path/to/old_dir /path/to/new_dir
 .Ed
 .Pp
 Same as above but excluding files matching the expressions
 .Dq *.h
 and
 .Dq *.c :
 .Bd -literal -offset indent
 $ diff -ruN -x '*.h' -x '*.c' /path/to/old_dir /path/to/new_dir
 .Ed
 .Pp
 Show a single line indicating if the files differ:
 .Bd -literal -offset indent
 $ diff -q /boot/loader.conf /boot/defaults/loader.conf
 Files /boot/loader.conf and /boot/defaults/loader.conf differ
 .Ed
 .Pp
 Assuming a file named
 .Pa example.txt
 with the following contents:
 .Bd -literal -offset indent
 FreeBSD is an operating system
 Linux is a kernel
 OpenBSD is an operating system
 .Ed
 .Pp
 Compare stdin with
 .Pa example.txt
 excluding from the comparison those lines containing either
 .Qq Linux
 or
 .Qq Open :
 .Bd -literal -offset indent
 $ echo "FreeBSD is an operating system" | diff -q -I 'Linux|Open' example.txt -
 .Ed
 .Sh SEE ALSO
 .Xr cmp 1 ,
 .Xr comm 1 ,
 .Xr diff3 1 ,
 .Xr ed 1 ,
 .Xr patch 1 ,
 .Xr pr 1 ,
 .Xr sdiff 1
 .Rs
 .%A James W. Hunt
 .%A M. Douglas McIlroy
 .%T "An Algorithm for Differential File Comparison"
 .%J Computing Science Technical Report
 .%Q Bell Laboratories 41
 .%D June 1976
 .Re
 .Sh STANDARDS
 The
 .Nm
 utility is compliant with the
 .St -p1003.1-2008
 specification.
 .Pp
 The flags
 .Op Fl aDdIiLlNnPpqSsTtwXxy
 are extensions to that specification.
 .Sh HISTORY
 A
 .Nm
 command appeared in
 .At v6 .
+The
+.Nm
+implimentation in
+.Fx 1.0
+until
+.Fx 11.4
+was GNU diff.  This was replaced in
+.Fx 12.0
+by a BSD licensed diff implimentation.  Some GNU'isms were lost in process.