maint: update copyright dates

Problem reported by Dan Jacobsen (bug#79959).
* src/diff.c (option_help_msgid): Tweak.

.prev-version

@@ -1 +1 @@
-3.11
+3.12

AUTHORS

@@ -33,7 +33,7 @@ Patrick D'Cruze
 Eli Zaretskii
 
 
-Copyright (C) 2001, 2006, 2009-2013, 2015-2025 Free Software Foundation, Inc.
+Copyright (C) 2001, 2006, 2009-2013, 2015-2026 Free Software Foundation, Inc.
 
 This file is part of GNU diffutils.
 

ChangeLog-2008

@@ -4265,7 +4265,7 @@ Thu Nov  3 16:30:24 1988  Randall Smith  (randy at gluteus.ai.mit.edu)
 
 	-----
 
-	Copyright (C) 1988-1994, 1997-2002, 2004, 2006, 2009-2013, 2015-2025
+	Copyright (C) 1988-1994, 1997-2002, 2004, 2006, 2009-2013, 2015-2026
 	Free Software Foundation, Inc.
 
 	Copying and distribution of this file, with or without

HACKING

@@ -568,7 +568,7 @@ Then just open the index.html file (in the generated lcov-html directory)
 in your favorite web browser.
 
 ========================================================================
-Copyright (C) 2009-2013, 2015-2025 Free Software Foundation, Inc.
+Copyright (C) 2009-2013, 2015-2026 Free Software Foundation, Inc.
 
 Permission is granted to copy, distribute and/or modify this document
 under the terms of the GNU Free Documentation License, Version 1.3 or

Makefile.am

@@ -1,6 +1,6 @@
 # Main Automakefile for GNU diffutils.
 
-# Copyright (C) 2001-2002, 2004, 2006, 2009-2013, 2015-2025 Free Software
+# Copyright (C) 2001-2002, 2004, 2006, 2009-2013, 2015-2026 Free Software
 # Foundation, Inc.
 
 # This program is free software: you can redistribute it and/or modify

NEWS

@@ -1,5 +1,8 @@
 GNU diffutils NEWS                                    -*- outline -*-
 
+* Noteworthy changes in release ?.? (????-??-??) [?]
+
+
 * Noteworthy changes in release 3.12 (2025-04-08) [stable]
 
 ** Bug fixes
@@ -545,7 +548,7 @@ User-visible changes in version 2.0:
 
 
 
-Copyright (C) 1993-1994, 1998, 2001-2002, 2004, 2006, 2009-2013, 2015-2025 Free
+Copyright (C) 1993-1994, 1998, 2001-2002, 2004, 2006, 2009-2013, 2015-2026 Free
 Software Foundation, Inc.
 
 This file is part of GNU Diffutils.

README

@@ -30,19 +30,12 @@ installation.  If you have an older version of libiconv, please
 upgrade to the latest one; see <ftp://ftp.gnu.org/gnu/libiconv/>.  If
 the problem seems isolated to diffutils, though, please report a bug.
 
-This program requires a Standard C compiler (C89 or later).  If you
+This program requires a Standard C compiler (C99 or later).  If you
 have a nonstandard compiler, please install GCC first.
 
 If you make changes to the source code, you may need appropriate
-versions of GNU build tools to regenerate the intermediate files.  The
+versions of GNU build tools to regenerate the intermediate files.
-following versions were used to generate the intermediate files in
+See README-prereq for details.
-this distribution:
-
-* Autoconf 2.59   <ftp://ftp.gnu.org/gnu/autoconf/autoconf-2.59.tar.gz>
-* Automake 1.8.3  <ftp://ftp.gnu.org/gnu/automake/automake-1.8.3.tar.gz>
-* gettext 0.14.1  <ftp://ftp.gnu.org/gnu/gettext/gettext-0.14.1.tar.gz>
-* help2man 1.33   <ftp://ftp.gnu.org/gnu/help2man/help2man-1.33.1.tar.gz>
-* Texinfo 4.7     <ftp://ftp.gnu.org/gnu/texinfo/texinfo-4.7.tar.gz>
 
 For any copyright year range specified as YYYY-ZZZZ in this package
 note that the range specifies every single year in that closed interval.
@@ -51,7 +44,7 @@ Please report bugs to <bug-diffutils@gnu.org>.
 
 -----
 
-Copyright (C) 1992, 1998, 2001-2002, 2004, 2009-2013, 2015-2025 Free Software
+Copyright (C) 1992, 1998, 2001-2002, 2004, 2009-2013, 2015-2026 Free Software
 Foundation, Inc.
 
 This file is part of GNU Diffutils.

README-hacking

@@ -119,7 +119,7 @@ diffutils:
 
 -----
 
-Copyright (C) 2002-2025 Free Software Foundation, Inc.
+Copyright (C) 2002-2026 Free Software Foundation, Inc.
 
 This program is free software: you can redistribute it and/or modify
 it under the terms of the GNU General Public License as published by

README-prereq

@@ -24,14 +24,14 @@ too-old versions first as they may be needed to build newer versions.
 
 Here is an example of how to build a program from source.  This
 example is for Autoconf; a similar approach should work for the other
-developer prerequisites.  This example assumes Autoconf 2.71; it
+developer prerequisites.  This example assumes Autoconf 2.72; it
 should be OK to use a later version of Autoconf, if available.
 
   prefix=$HOME/prefix   # (or wherever else you choose)
   export PATH=$prefix/bin:$PATH
-  wget https://ftp.gnu.org/pub/gnu/autoconf/autoconf-2.71.tar.gz
+  wget https://ftp.gnu.org/pub/gnu/autoconf/autoconf-2.72.tar.gz
-  gzip -d <autoconf-2.71.tar.gz | tar xf -
+  gzip -d <autoconf-2.72.tar.gz | tar xf -
-  cd autoconf-2.71
+  cd autoconf-2.72
   ./configure --prefix=$prefix
   make install
 

bootstrap

@@ -3,9 +3,9 @@
 
 # Bootstrap this package from checked-out sources.
 
-scriptversion=2024-07-04.10; # UTC
+scriptversion=2025-06-10.02; # UTC
 
-# Copyright (C) 2003-2025 Free Software Foundation, Inc.
+# Copyright (C) 2003-2026 Free Software Foundation, Inc.
 #
 # This program is free software: you can redistribute it and/or modify
 # it under the terms of the GNU General Public License as published by
@@ -37,9 +37,9 @@ medir=`dirname "$me"`
 
 # A library of shell functions for autopull.sh, autogen.sh, and bootstrap.
 
-scriptlibversion=2025-02-16.12; # UTC
+scriptlibversion=2025-12-04.19; # UTC
 
-# Copyright (C) 2003-2025 Free Software Foundation, Inc.
+# Copyright (C) 2003-2026 Free Software Foundation, Inc.
 #
 # This program is free software: you can redistribute it and/or modify
 # it under the terms of the GNU General Public License as published by
@@ -72,7 +72,7 @@ export LC_ALL
 # Honor $PERL, but work even if there is none.
 PERL="${PERL-perl}"
 
-default_gnulib_url=https://git.savannah.gnu.org/git/gnulib.git
+default_gnulib_url=https://https.git.savannah.gnu.org/git/gnulib.git
 
 # Copyright year, for the --version output.
 copyright_year=`echo "$scriptlibversion" | sed -e 's/[^0-9].*//'`
@@ -861,7 +861,8 @@ autopull()
     elif check_exists git-merge-changelog; then
       echo "$0: initializing git-merge-changelog driver"
       git config merge.merge-changelog.name 'GNU-style ChangeLog merge driver'
-      git config merge.merge-changelog.driver 'git-merge-changelog %O %A %B'
+      git config merge.merge-changelog.driver \
+          'git-merge-changelog %O %A %B "%Y"'
     else
       echo "$0: consider installing git-merge-changelog from gnulib"
     fi
@@ -1337,7 +1338,7 @@ autogen()
 
   # Invoke autoreconf with --force --install to ensure upgrades of tools
   # such as ylwrap.
-  AUTORECONFFLAGS="--verbose --install --force -I $m4_base $ACLOCAL_FLAGS"
+  AUTORECONFFLAGS="--verbose --install --force $ACLOCAL_FLAGS"
   AUTORECONFFLAGS="$AUTORECONFFLAGS --no-recursive"
 
   # Tell autoreconf not to invoke autopoint or libtoolize; they were run above.
@@ -1413,7 +1414,7 @@ autogen()
 # Local Variables:
 # eval: (add-hook 'before-save-hook 'time-stamp nil t)
 # time-stamp-start: "scriptlibversion="
-# time-stamp-format: "%:y-%02m-%02d.%02H"
+# time-stamp-format: "%Y-%02m-%02d.%02H"
 # time-stamp-time-zone: "UTC0"
 # time-stamp-end: "; # UTC"
 # End:
@@ -1624,7 +1625,7 @@ fi
 # Local Variables:
 # eval: (add-hook 'before-save-hook 'time-stamp nil t)
 # time-stamp-start: "scriptversion="
-# time-stamp-format: "%:y-%02m-%02d.%02H"
+# time-stamp-format: "%Y-%02m-%02d.%02H"
 # time-stamp-time-zone: "UTC0"
 # time-stamp-end: "; # UTC"
 # End:

bootstrap.conf

@@ -1,6 +1,6 @@
 # Bootstrap configuration.
 
-# Copyright (C) 2006-2013, 2015-2025 Free Software Foundation, Inc.
+# Copyright (C) 2006-2013, 2015-2026 Free Software Foundation, Inc.
 
 # This program is free software: you can redistribute it and/or modify
 # it under the terms of the GNU General Public License as published by
@@ -16,12 +16,31 @@
 # along with this program.  If not, see <http://www.gnu.org/licenses/>.
 
 avoided_gnulib_modules='
-  --avoid=localename
+  --avoid=hard-locale
+  --avoid=localename-unsafe
+  --avoid=localename-unsafe-limited
   --avoid=lock-tests
   --avoid=mbuiter
   --avoid=mbuiterf
   --avoid=setlocale
 '
+# These tests depend on localcharset, which we avoid.
+avoided_gnulib_tests='
+  --avoid=c32width-tests
+  --avoid=quotearg-simple-tests
+  --avoid=regex-tests
+  --avoid=wcwidth-tests
+'
+# These test whether all bytes are valid in the C locale,
+# which we don't care about.
+avoided_gnulib_tests=$avoided_gnulib_tests'
+  --avoid=btoc32-tests
+  --avoid=btowc-tests
+  --avoid=mbrtoc32-tests
+  --avoid=mbrtowc-tests
+  --avoid=mbsrtoc32s-tests
+  --avoid=mbsrtowcs-tests
+'
 
 # gnulib modules used by this package.
 gnulib_modules='
@@ -66,7 +85,6 @@ gnu-make
 gnu-web-doc-update
 gnumakefile
 gnupload
-hard-locale
 ialloc
 idx
 intprops
@@ -81,7 +99,7 @@ mempcpy
 minmax
 mkstemp
 mktime
-nstrftime
+nstrftime-limited
 nullptr
 openat
 pclose
@@ -105,8 +123,9 @@ stat
 stat-macros
 stat-size
 stat-time
-stdckdint-h
 stdc_bit_width
+stdckdint-h
+stdcountof-h
 stdint-h
 stpcpy
 strcase
@@ -149,6 +168,7 @@ gnulib_tool_option_extras="--tests-base=gnulib-tests
  --symlink
  --makefile-name=gnulib.mk
  $avoided_gnulib_modules
+ $avoided_gnulib_tests
 "
 
 # Build prerequisites

cfg.mk

@@ -1,5 +1,5 @@
 # Customize maint.mk                           -*- makefile -*-
-# Copyright (C) 2003-2013, 2015-2025 Free Software Foundation, Inc.
+# Copyright (C) 2003-2013, 2015-2026 Free Software Foundation, Inc.
 
 # This program is free software: you can redistribute it and/or modify
 # it under the terms of the GNU General Public License as published by
@@ -36,7 +36,7 @@ announcement_Cc_ = $(translation_project_), $(PACKAGE)-devel@gnu.org
 # Now that we have better tests, make this the default.
 export VERBOSE = yes
 
-old_NEWS_hash = eefa9b0b34af4272f659040508d9acd0
+old_NEWS_hash = cfdcec044a361bf0e7b4e860bacc3d53
 
 # Tell maint.mk's syntax-check rules that diff gets config.h directly or
 # via diff.h or system.h.

configure.ac

@@ -1,6 +1,6 @@
 # Configure template for GNU Diffutils.
 
-# Copyright (C) 1994-1995, 1998, 2001-2002, 2004, 2006, 2009-2013, 2015-2025
+# Copyright (C) 1994-1995, 1998, 2001-2002, 2004, 2006, 2009-2013, 2015-2026
 # Free Software Foundation, Inc.
 
 # This program is free software: you can redistribute it and/or modify
@@ -37,6 +37,18 @@ AC_PROG_AWK
 AC_PROG_CC
 AM_MISSING_PROG([HELP2MAN], [help2man])
 AC_PROG_RANLIB
+
+# Do not worry about multibyte C locales.
+# This removes dependencies on hard-locale etc.
+gl_cv_func_mbrtowc_C_locale_sans_EILSEQ="guessing yes"
+gl_cv_func_mbrtoc32_C_locale_sans_EILSEQ="guessing yes"
+
+# Default Gnulib configuration to no multithreading,
+# since diffutils is single-threaded.
+# Although the builder can override this with the --enable-threads option
+# of 'configure', diffutils does not support that on all platforms.
+m4_define([gl_THREADLIB_DEFAULT_NO])
+
 gl_EARLY
 gl_USE_SYSTEM_EXTENSIONS
 gl_INIT
@@ -59,6 +71,15 @@ AC_DEFINE([GNULIB_MBRTOC32_REGULAR], [1],
   [Do not worry about rare encodings like CP864, EBCDIC, Johab, and Shift JIS
    that glibc does not support.])
 
+AC_DEFINE([REQUIRE_GNUISH_STRFTIME_AM_PM], [0],
+  [Do not worry about GNU strftime behavior for AM and PM indicators.])
+AC_DEFINE([SUPPORT_NON_GREG_CALENDARS_IN_STRFTIME], [false],
+  [Do not worry about GNU strftime behavior for non-Gregorian calendars.])
+
+# Diffutils translates Gnulib's msgids too.
+AC_DEFINE([GNULIB_TEXT_DOMAIN], [PACKAGE],
+  [Textdomain to use when translating Gnulib's msgids.])
+
 AC_C_INLINE
 
 AC_CHECK_MEMBERS([struct stat.st_rdev])
@@ -66,10 +87,6 @@ AC_HEADER_DIRENT
 AC_HEADER_SYS_WAIT
 AC_TYPE_PID_T
 
-AC_CHECK_FUNCS_ONCE([sigaction sigprocmask])
-if test $ac_cv_func_sigprocmask = no; then
-  AC_CHECK_FUNCS([sigblock])
-fi
 AC_FUNC_FORK
 
 dnl O_PATH exists since Linux 2.6.39, but is supported with fstat() only since
@@ -184,8 +201,8 @@ AC_DEFINE_UNQUOTED([PR_PROGRAM], ["$PR_PROGRAM"], [Name of "pr" program.])
 
 # When .tarball-version exists, we're building from a tarball
 # and must not make man/*.1 files depend on the generated src/version.c,
-# because that would induce a requirement to run the help2man perl script.
+# because that would induce a requirement to run help2man.
-# We are not yet prepared to make perl a build-from-tarball requirement.
+# We are not yet prepared to make help2man a build-from-tarball requirement.
 # Hence, here we detect .tarball-version existence.  When not present,
 # we define a variable to be used in man/Makefile.am to induce the
 # proper dependency (so that man/*.1 will be rebuilt upon any version change),
@@ -195,7 +212,7 @@ test -f $srcdir/.tarball-version \
   && SRC_VERSION_C= \
   || SRC_VERSION_C=../src/version.c
 
-AM_GNU_GETTEXT([external], [need-ngettext])
+AM_GNU_GETTEXT([external], [need-formatstring-macros])
 AM_GNU_GETTEXT_VERSION([0.19.2])
 XGETTEXT="AWK='$AWK' \$(SHELL) \$(top_srcdir)/exgettext $XGETTEXT"
 

doc/Makefile.am

@@ -1,6 +1,6 @@
 # Makefile for GNU diffutils documentation.
 
-# Copyright (C) 2001-2002, 2009-2013, 2015-2025 Free Software Foundation, Inc.
+# Copyright (C) 2001-2002, 2009-2013, 2015-2026 Free Software Foundation, Inc.
 
 # This program is free software: you can redistribute it and/or modify
 # it under the terms of the GNU General Public License as published by

doc/diffutils.texi

@@ -17,7 +17,7 @@ and documents the GNU @command{diff}, @command{diff3},
 differences between files and the GNU @command{patch} command for
 using their output to update files.
 
-Copyright @copyright{} 1992--1994, 1998, 2001--2002, 2004, 2006, 2009--2025
+Copyright @copyright{} 1992--1994, 1998, 2001--2002, 2004, 2006, 2009--2026
 Free Software Foundation, Inc.
 
 @quotation
@@ -4016,7 +4016,7 @@ found.  @xref{Comparing Directories}.
 
 @item -s
 @itemx --report-identical-files
-Report when two files are the same.  @xref{Comparing Directories}.
+Also report when two files are the same.  @xref{Comparing Directories}.
 
 @item -S @var{file}
 @itemx --starting-file=@var{file}

doc/fdl.texi

@@ -5,7 +5,7 @@
 @c hence no sectioning command or @node.
 
 @display
-Copyright @copyright{} 2000--2002, 2007--2008, 2022--2025 Free Software
+Copyright @copyright{} 2000--2002, 2007--2008, 2022--2026 Free Software
 Foundation, Inc.
 @uref{https://fsf.org/}
 

exgettext

@@ -1,7 +1,7 @@
 #! /bin/sh
 # Wrapper around gettext for programs using the msgid convention.
 
-# Copyright (C) 1998, 2001, 2004, 2009-2013, 2015-2025 Free Software
+# Copyright (C) 1998, 2001, 2004, 2009-2013, 2015-2026 Free Software
 # Foundation, Inc.
 
 # Written by Paul Eggert <eggert@twinsun.com>.

gnulib

@@ -1 +1 @@
-Subproject commit 3773db653242ab7165cd300295c27405e4f9cc79
+Subproject commit 4f6ac2c3c689cd7312b5f9da97791b14bbc2ee53

gnulib-tests/Makefile.am

@@ -1 +1,3 @@
+AM_CFLAGS =
+
 include gnulib.mk

lib/Makefile.am

@@ -1,6 +1,6 @@
 # Automakefile for GNU Diffutils library.
 
-# Copyright (C) 2001-2002, 2004, 2006, 2009-2013, 2015-2025 Free Software
+# Copyright (C) 2001-2002, 2004, 2006, 2009-2013, 2015-2026 Free Software
 # Foundation, Inc.
 
 # This program is free software: you can redistribute it and/or modify

lib/cmpbuf.c

@@ -1,6 +1,6 @@
 /* Buffer primitives for comparison operations.
 
-   Copyright (C) 1993, 1995, 1998, 2001-2002, 2006, 2009-2013, 2015-2025 Free
+   Copyright (C) 1993, 1995, 1998, 2001-2002, 2006, 2009-2013, 2015-2026 Free
    Software Foundation, Inc.
 
    This program is free software: you can redistribute it and/or modify

lib/cmpbuf.h

@@ -1,6 +1,6 @@
 /* Buffer primitives for comparison operations.
 
-   Copyright (C) 2002, 2009-2013, 2015-2025 Free Software Foundation, Inc.
+   Copyright (C) 2002, 2009-2013, 2015-2026 Free Software Foundation, Inc.
 
    This program is free software: you can redistribute it and/or modify
    it under the terms of the GNU General Public License as published by

lib/diagnose.c

@@ -1,6 +1,6 @@
 /* Diagnostics for GNU diffutils
 
-   Copyright 2023-2025 Free Software Foundation, Inc.
+   Copyright 2023-2026 Free Software Foundation, Inc.
 
    This file is part of GNU DIFF.
 

man/Makefile.am

@@ -1,6 +1,6 @@
 # Automakefile for GNU diffutils man pages
 
-# Copyright (C) 2002, 2009-2013, 2015-2025 Free Software Foundation, Inc.
+# Copyright (C) 2002, 2009-2013, 2015-2026 Free Software Foundation, Inc.
 
 # This program is free software: you can redistribute it and/or modify
 # it under the terms of the GNU General Public License as published by
@@ -16,7 +16,7 @@
 # along with this program.  If not, see <http://www.gnu.org/licenses/>.
 
 dist_man1_MANS = cmp.1 diff.1 diff3.1 sdiff.1
-EXTRA_DIST = $(dist_man1_MANS:%.1=%.x) help2man
+EXTRA_DIST = $(dist_man1_MANS:%.1=%.x)
 MAINTAINERCLEANFILES = $(dist_man1_MANS)
 
 S = $(top_srcdir)/src
@@ -29,13 +29,13 @@ sdiff.1: $S/sdiff.c sdiff.x
 # to ensure help2man invokes them via the use of PATH below.
 bin_dir = ../src
 
-# Depend on the former to get version number changes.
+# Depend on $(SRC_VERSION_C) to get version number changes.
-$(dist_man1_MANS): $(SRC_VERSION_C) help2man
+$(dist_man1_MANS): $(SRC_VERSION_C)
 	$(AM_V_GEN)base=`expr $@ : '\(.*\).1'`				\
 	  && test -x $(bin_dir)/$$base					\
 	  && (echo '[NAME]'						\
 	      && sed 's@/\* *@@; s/-/\\-/;s/^GNU //; q' $S/$$base.c)	\
 	     | PATH="$(bin_dir)$(PATH_SEPARATOR)$$PATH"			\
-	       $(srcdir)/help2man -i - -i $(srcdir)/$$base.x		\
+	       $(HELP2MAN) -i - -i $(srcdir)/$$base.x			\
 		 -S '$(PACKAGE) $(VERSION)' $$base > $$base.1-t		\
 	  && mv $$base.1-t $(srcdir)/$$base.1

man/help2man

@@ -1,801 +0,0 @@
-#!/usr/bin/env perl
-
-# Generate a short man page from --help and --version output.
-# Copyright (C) 1997-2005, 2009-2017, 2020-2021, 2025 Free Software Foundation,
-# Inc.
-
-# This program is free software; you can redistribute it and/or modify
-# it under the terms of the GNU General Public License as published by
-# the Free Software Foundation; either version 3, or (at your option)
-# any later version.
-
-# This program is distributed in the hope that it will be useful,
-# but WITHOUT ANY WARRANTY; without even the implied warranty of
-# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
-# GNU General Public License for more details.
-
-# You should have received a copy of the GNU General Public License
-# along with this program; if not, see <https://www.gnu.org/licenses/>.
-
-# Written by Brendan O'Dea <bod@debian.org>
-# Available from https://ftp.gnu.org/gnu/help2man/
-
-use 5.008;
-use strict;
-use warnings;
-use Getopt::Long;
-use Text::ParseWords qw(shellwords);
-use Text::Tabs qw(expand);
-use POSIX qw(strftime setlocale LC_ALL);
-
-my $this_program = 'help2man';
-my $this_version = '1.48.5';
-
-sub _ { $_[0] }
-sub configure_locale
-{
-    my $locale = shift;
-    die "$this_program: no locale support (Locale::gettext required)\n"
-	unless $locale eq 'C';
-}
-
-sub dec { $_[0] }
-sub enc { $_[0] }
-sub enc_user { $_[0] }
-sub kark { die +(sprintf shift, @_), "\n" }
-sub N_ { $_[0] }
-
-sub program_basename;
-sub get_option_value;
-sub convert_option;
-sub fix_italic_spacing;
-
-my $version_info = enc_user sprintf _(<<'EOT'), $this_program, $this_version;
-GNU %s %s
-
-Copyright (C) 1997-2005, 2009-2017, 2020-2021, 2025 Free Software Foundation,
-Inc.
-This is free software; see the source for copying conditions.  There is NO
-warranty; not even for MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
-
-Written by Brendan O'Dea <bod@debian.org>
-EOT
-
-my $help_info = enc_user sprintf _(<<'EOT'), $this_program, $this_program;
-`%s' generates a man page out of `--help' and `--version' output.
-
-Usage: %s [OPTION]... EXECUTABLE
-
- -n, --name=STRING       description for the NAME paragraph
- -s, --section=SECTION   section number for manual page (1, 6, 8)
- -m, --manual=TEXT       name of manual (User Commands, ...)
- -S, --source=TEXT       source of program (FSF, Debian, ...)
- -L, --locale=STRING     select locale (default "C")
- -i, --include=FILE      include material from `FILE'
- -I, --opt-include=FILE  include material from `FILE' if it exists
- -o, --output=FILE       send output to `FILE'
- -p, --info-page=TEXT    name of Texinfo manual
- -N, --no-info           suppress pointer to Texinfo manual
- -l, --libtool           exclude the `lt-' from the program name
- -b, --bold-refs         apply bold style to references
-     --help              print this help, then exit
-     --version           print version number, then exit
-
-EXECUTABLE should accept `--help' and `--version' options and produce output on
-stdout although alternatives may be specified using:
-
- -h, --help-option=STRING     help option string
- -v, --version-option=STRING  version option string
- --version-string=STRING      version string
- --no-discard-stderr          include stderr when parsing option output
-
-Report bugs to <bug-help2man@gnu.org>.
-EOT
-
-my $section = 1;
-my $manual = '';
-my $source = '';
-my $help_option = '--help';
-my $version_option = '--version';
-my $discard_stderr = 1;
-my ($opt_name, @opt_include, $opt_output, $opt_info, $opt_no_info, $opt_libtool,
-    $opt_bold_refs, $version_text);
-
-my %opt_def = (
-    'n|name=s'		 => \$opt_name,
-    's|section=s'	 => \$section,
-    'm|manual=s'	 => \$manual,
-    'S|source=s'	 => \$source,
-    'L|locale=s'	 => sub { configure_locale pop },
-    'i|include=s'	 => sub { push @opt_include, [ pop, 1 ] },
-    'I|opt-include=s'	 => sub { push @opt_include, [ pop, 0 ] },
-    'o|output=s'	 => \$opt_output,
-    'p|info-page=s'	 => \$opt_info,
-    'N|no-info'		 => \$opt_no_info,
-    'l|libtool'		 => \$opt_libtool,
-    'b|bold-refs'	 => \$opt_bold_refs,
-    'help'		 => sub { print $help_info; exit },
-    'version'		 => sub { print $version_info; exit },
-    'h|help-option=s'	 => \$help_option,
-    'v|version-option=s' => \$version_option,
-    'version-string=s'	 => \$version_text,
-    'discard-stderr!'	 => \$discard_stderr,
-);
-
-# Parse options.
-Getopt::Long::config('bundling');
-die $help_info unless GetOptions %opt_def and @ARGV == 1;
-
-my %include = ();
-my %replace = ();
-my %append = ();
-my %append_match = ();
-my @sections = ();  # retain order of include file or in-line *section*s
-
-# Process include file (if given).  Format is:
-#
-#   Optional initial text, ignored.  May include lines starting with `-'
-#   which are processed as options.
-#
-#   [section]
-#   Verbatim text to be included in the named section.  By default at
-#   the start, but in the case of `name' and `synopsis' the content
-#   will replace the autogenerated contents.
-#
-#   [<section]
-#   Verbatim text to be inserted at the start of the named section.
-#
-#   [=section]
-#   Verbatim text to replace the named section.
-#
-#   [>section]
-#   Verbatim text to be appended to the end of the named section.
-#
-#   /pattern/
-#   Verbatim text for inclusion below a paragraph matching `pattern'.
-#
-
-while (@opt_include)
-{
-    my ($inc, $required) = @{shift @opt_include};
-
-    next unless -f $inc or $required;
-    kark N_("%s: can't open `%s' (%s)"), $this_program, $inc, $!
-	unless open INC, $inc;
-
-    my $key;
-    my $hash;
-
-    while (<INC>)
-    {
-	# Convert input to internal Perl format, so that multibyte
-	# sequences are treated as single characters.
-	$_ = dec $_;
-
-	# [section]
-	if (/^\[([^]]+)\]\s*$/)
-	{
-	    $key = uc $1;
-	    $key =~ s/^\s+//;
-	    $key =~ s/\s+$//;
-	    $hash = \%include;
-	    # Handle explicit [<section], [=section] and [>section]
-	    if ($key =~ s/^([<>=])\s*//)
-	    {
-		if    ($1 eq '>') { $hash = \%append; }
-		elsif ($1 eq '=') { $hash = \%replace; }
-	    }
-	    # NAME/SYNOPSIS replace by default
-	    elsif ($key eq _('NAME') or $key eq _('SYNOPSIS'))
-	    {
-		$hash = \%replace;
-	    }
-	    else
-	    {
-		$hash = \%include;
-	    }
-
-	    push @sections, $key;
-	    next;
-	}
-
-	# /pattern/
-	if (m!^/(.*)/([ims]*)\s*$!)
-	{
-	    my $pat = $2 ? "(?$2)$1" : $1;
-
-	    # Check pattern.
-	    eval { $key = qr($pat) };
-	    if ($@)
-	    {
-		$@ =~ s/ at .*? line \d.*//;
-		die "$inc:$.:$@";
-	    }
-
-	    $hash = \%append_match;
-	    next;
-	}
-
-	# Check for options before the first section--anything else is
-	# silently ignored, allowing the first for comments and
-	# revision info.
-	unless ($key)
-	{
-	    # handle options
-	    if (/^-/)
-	    {
-		local @ARGV = shellwords $_;
-		GetOptions %opt_def;
-	    }
-
-	    next;
-	}
-
-	$hash->{$key} .= $_;
-    }
-
-    close INC;
-
-    kark N_("%s: no valid information found in `%s'"), $this_program, $inc
-	unless $key;
-}
-
-# Compress trailing blank lines.
-for my $hash (\(%include, %replace, %append, %append_match))
-{
-    for (keys %$hash) { $hash->{$_} =~ s/\n+$/\n/ }
-}
-
-# Grab help and version info from executable.
-my $help_text   = get_option_value $ARGV[0], $help_option;
-$version_text ||= get_option_value $ARGV[0], $version_option;
-
-# By default the generated manual pages will include the current date.  This may
-# however be overridden by setting the environment variable $SOURCE_DATE_EPOCH
-# to an integer value of the seconds since the UNIX epoch.  This is primarily
-# intended to support reproducible builds (wiki.debian.org/ReproducibleBuilds)
-# and will additionally ensure that the output date string is UTC.
-my $epoch_secs = time;
-if (exists $ENV{SOURCE_DATE_EPOCH} and $ENV{SOURCE_DATE_EPOCH} =~ /^(\d+)$/)
-{
-    $epoch_secs = $1;
-    $ENV{TZ} = 'UTC0';
-}
-
-# Translators: the following message is a strftime(3) format string, which in
-# the English version expands to the month as a word and the full year.  It
-# is used on the footer of the generated manual pages.  If in doubt, you may
-# just use %x as the value (which should be the full locale-specific date).
-my $date = enc strftime _("%B %Y"), localtime $epoch_secs;
-my $program = program_basename $ARGV[0];
-my $package = $program;
-my $version;
-
-if ($opt_output)
-{
-    unlink $opt_output or kark N_("%s: can't unlink %s (%s)"),
-	$this_program, $opt_output, $! if -e $opt_output;
-
-    open STDOUT, ">$opt_output"
-	or kark N_("%s: can't create %s (%s)"), $this_program, $opt_output, $!;
-}
-
-# The first line of the --version information is assumed to be in one
-# of the following formats:
-#
-#   <version>
-#   <program> <version>
-#   {GNU,Free} <program> <version>
-#   <program> ({GNU,Free,} <package>) <version>
-#   <program> - {GNU,Free,} <package> <version>
-#   <program> - {GNU,Free,} <package> - <version>
-#
-# and separated from any copyright/author details by a blank line.
-
-($_, $version_text) = ((split /\n+/, $version_text, 2), '');
-
-if (/^(\S+) +\(((?:(?:GNU|Free) +)?[^)]+)\) +(\S.*)$/ or
-    /^(\S+) +- +((?:(?:GNU|Free) +)?\S.*) +- +(\S.*)$/ or
-    /^(\S+) +- +((?:(?:GNU|Free) +)?\S+) +(\S.*)$/)
-{
-    $program = program_basename $1;
-    $package = $2;
-    $version = $3;
-}
-elsif (/^((?:GNU|Free) +)?(\S+) +(\S.*)$/)
-{
-    $program = program_basename $2;
-    $package = $1 ? "$1$program" : $program;
-    $version = $3;
-}
-else
-{
-    $version = $_;
-}
-
-# No info for `info' itself.
-$opt_no_info = 1 if $program eq 'info';
-
-if ($opt_name)
-{
-    # --name overrides --include contents.
-    $replace{_('NAME')} = "$program \\- $opt_name\n";
-}
-
-# Translators: "NAME", "SYNOPSIS" and other one or two word strings in all
-# upper case are manual page section headings.  The man(1) manual page in your
-# language, if available should provide the conventional translations.
-for ($replace{_('NAME')} || ($include{_('NAME')} ||= ''))
-{
-    if ($_) # Use first name given as $program
-    {
-	$program = $1 if /^([^\s,]+)(?:,?\s*[^\s,\\-]+)*\s+\\?-/;
-    }
-    else # Set a default (useless) NAME paragraph.
-    {
-	$_ = sprintf _("%s \\- manual page for %s %s") . "\n", $program,
-	    $program, $version;
-    }
-}
-
-# Man pages traditionally have the page title in caps.
-my $PROGRAM = uc $program;
-
-# Set default page head/footers
-$source ||= "$package $version";
-unless ($manual)
-{
-    for ($section)
-    {
-	if (/^(1[Mm]|8)/) { $manual = enc _('System Administration Utilities') }
-	elsif (/^6/)	  { $manual = enc _('Games') }
-	else		  { $manual = enc _('User Commands') }
-    }
-}
-
-# Extract usage clause(s) [if any] for SYNOPSIS.
-# Translators: "Usage" and "or" here are patterns (regular expressions) which
-# are used to match the usage synopsis in program output.  An example from cp
-# (GNU coreutils) which contains both strings:
-#  Usage: cp [OPTION]... [-T] SOURCE DEST
-#    or:  cp [OPTION]... SOURCE... DIRECTORY
-#    or:  cp [OPTION]... -t DIRECTORY SOURCE...
-my $PAT_USAGE = _('Usage');
-my $PAT_USAGE_CONT = _('or');
-if ($help_text =~ s/^($PAT_USAGE):( +(\S+))(.*)((?:\n(?: {6}\1| *($PAT_USAGE_CONT): +\S).*)*)//om)
-{
-    my @syn = $3 . $4;
-
-    if ($_ = $5)
-    {
-	s/^\n//;
-	for (split /\n/) { s/^ *(($PAT_USAGE_CONT): +)?//o; push @syn, $_ }
-    }
-
-    my $synopsis = '';
-    for (@syn)
-    {
-	$synopsis .= ".br\n" if $synopsis;
-	s!^\S*/!!;
-	s/^lt-// if $opt_libtool;
-	s/^(\S+) *//;
-	$synopsis .= ".B $1\n";
-	s/\s+$//;
-	s/(([][]|\.\.+)+)/\\fR$1\\fI/g;
-	s/^/\\fI/ unless s/^\\fR//;
-	$_ .= '\fR';
-	s/(\\fI)( *)/$2$1/g;
-	s/\\fI\\fR//g;
-	s/^\\fR//;
-	s/\\fI$//;
-	s/^\./\\&./;
-
-	$_ = fix_italic_spacing $_;
-	$synopsis .= "$_\n";
-    }
-
-    $include{_('SYNOPSIS')} .= $synopsis;
-}
-
-# Process text, initial section is DESCRIPTION.
-my $sect = _('DESCRIPTION');
-$_ = "$help_text\n\n$version_text";
-
-# Normalise paragraph breaks.
-s/^\n+//;
-s/\n*$/\n/;
-s/\n\n+/\n\n/g;
-
-# Join hyphenated lines.
-s/([A-Za-z])-\n *([A-Za-z])/$1$2/g;
-
-# Temporarily exchange leading dots, apostrophes and backslashes for
-# tokens.
-s/^\./\x80/mg;
-s/^'/\x81/mg;
-s/\\/\x82/g;
-
-# Translators: patterns are used to match common program output. In the source
-# these strings are all of the form of "my $PAT_something = _('...');" and are
-# regular expressions.  If there is more than one commonly used string, you
-# may separate alternatives with "|".  Spaces in these expressions are written
-# as " +" to indicate that more than one space may be matched.  The string
-# "(?:[\\w-]+ +)?" in the bug reporting pattern is used to indicate an
-# optional word, so that either "Report bugs" or "Report _program_ bugs" will
-# be matched.
-my $PAT_BUGS          = _('Report +(?:[\w-]+ +)?bugs|' .
-                          'Email +bug +reports +to|' .
-                          '.* +online +help:');
-my $PAT_AUTHOR        = _('Written +by');
-my $PAT_OPTIONS       = _('Options');
-my $PAT_ENVIRONMENT   = _('Environment');
-my $PAT_FILES         = _('Files');
-my $PAT_EXAMPLES      = _('Examples');
-my $PAT_FREE_SOFTWARE = _('This +is +free +software');
-my $PAT_SEE_ALSO      = _('Full +documentation');
-
-# Start a new paragraph (if required) for these.
-s/([^\n])\n($PAT_BUGS|$PAT_AUTHOR|$PAT_SEE_ALSO) /$1\n\n$2 /og;
-
-# Convert iso-8859-1 copyright symbol or (c) to nroff
-# character.
-s/^Copyright +(?:\xa9|\([Cc]\))/Copyright \\(co/mg;
-
-while (length)
-{
-    # Convert some standard paragraph names.
-    if (s/^($PAT_OPTIONS): *\n+//o)
-    {
-	$sect = _('OPTIONS');
-	next;
-    }
-    if (s/^($PAT_ENVIRONMENT): *\n+//o)
-    {
-	$sect = _('ENVIRONMENT');
-	next;
-    }
-    if (s/^($PAT_FILES): *\n+//o)
-    {
-	$sect = _('FILES');
-	next;
-    }
-    elsif (s/^($PAT_EXAMPLES): *\n+//o)
-    {
-	$sect = _('EXAMPLES');
-	next;
-    }
-
-    # Custom section indicated by a line containing "*Section Name*".
-    if (s/^\*(\w(.*\w)?)\* *\n+//)
-    {
-	$sect = uc $1;
-	$sect =~ tr/*/ /;  # also accept *Section*Name*
-	push @sections, $sect;
-	next;
-    }
-
-    # Copyright section.
-    if (/^Copyright /)
-    {
-	$sect = _('COPYRIGHT');
-    }
-
-    # Bug reporting section.
-    elsif (/^($PAT_BUGS) /o)
-    {
-	$sect = _('REPORTING BUGS');
-    }
-
-    # Author section.
-    elsif (/^($PAT_AUTHOR)/o)
-    {
-	$sect = _('AUTHOR');
-    }
-
-    elsif (/^($PAT_SEE_ALSO)/o)
-    {
-	$sect = _('SEE ALSO');
-	$opt_no_info = 1;
-    }
-
-    # Examples, indicated by an indented leading $, % or > are
-    # rendered in a constant width font.
-    if (/^( +)([\$\%>] )\S/)
-    {
-	my $indent = $1;
-	my $prefix = $2;
-	my $break = '.IP';
-	while (s/^$indent\Q$prefix\E(\S.*)\n*//)
-	{
-	    $include{$sect} .= "$break\n\\f(CW$prefix$1\\fR\n";
-	    $break = '.br';
-	}
-
-	next;
-    }
-
-    my $matched = '';
-
-    # Sub-sections have a trailing colon and the second line indented.
-    if (s/^(\S.*:) *\n / /)
-    {
-	$matched .= $& if %append_match;
-	$include{$sect} .= qq(.SS "$1"\n);
-    }
-
-    my $indent = 0;
-    my $content = '';
-
-    # Option with description.
-    if (s/^( {1,10}([+-]\S.*?))(?:(  +(?!-))|\n( {20,}))(\S.*)\n//)
-    {
-	$matched .= $& if %append_match;
-	$indent = length ($4 || "$1$3");
-	$content = ".TP\n\x84$2\n\x84$5\n";
-	unless ($4)
-	{
-	    # Indent may be different on second line.
-	    $indent = length $& if /^ {20,}/;
-	}
-    }
-
-    # Option without description.
-    elsif (s/^ {1,10}([+-]\S.*)\n//)
-    {
-	$matched .= $& if %append_match;
-	$content = ".HP\n\x84$1\n";
-	$indent = 80; # not continued
-    }
-
-    # Indented paragraph with tag.
-    elsif (s/^( +(\S.*?)  +)(\S.*)\n//)
-    {
-	$matched .= $& if %append_match;
-	$indent = length $1;
-	$content = ".TP\n\x84$2\n\x84$3\n";
-    }
-
-    # Indented paragraph.
-    elsif (s/^( +)(\S.*)\n//)
-    {
-	$matched .= $& if %append_match;
-	$indent = length $1;
-	$content = ".IP\n\x84$2\n";
-    }
-
-    # Left justified paragraph.
-    else
-    {
-	s/(.*)\n//;
-	$matched .= $& if %append_match;
-	$content = ".PP\n" if $include{$sect};
-	$content .= "$1\n";
-    }
-
-    # Append continuations.
-    while ($indent ? s/^ {$indent}(\S.*)\n// : s/^(\S.*)\n//)
-    {
-	$matched .= $& if %append_match;
-	$content .= "\x84$1\n";
-    }
-
-    # Move to next paragraph.
-    s/^\n+//;
-
-    for ($content)
-    {
-	# Leading dot and apostrophe protection.
-	s/\x84\./\x80/g;
-	s/\x84'/\x81/g;
-	s/\x84//g;
-
-	# Examples should be verbatim.
-	unless ($sect eq _('EXAMPLES'))
-	{
-	    # Convert options.
-	    s/(^|[ (])(-[][\w=-]+)/$1 . convert_option $2/mge;
-
-	    # Italicise filenames: /a/b, $VAR/c/d, ~/e/f
-	    s!
-		(^|[ (])			# space/punctuation before
-		(
-		    (?:\$\w+|~)?		# leading variable, or tilde
-		    (?:/\w(?:[\w.-]*\w)?)+	# path components
-		)
-		($|[ ,;.)])			# space/punctuation after
-	    !$1\\fI$2\\fP$3!xmg;
-
-	    $_ = fix_italic_spacing $_;
-	}
-
-	# Escape remaining hyphens.
-	s/-/\x83/g;
-
-	if ($sect eq _('COPYRIGHT'))
-	{
-	    # Insert line breaks before additional copyright messages
-	    # and the disclaimer.
-	    s/\n(Copyright |$PAT_FREE_SOFTWARE)/\n.br\n$1/og;
-	}
-	elsif ($sect eq _('REPORTING BUGS'))
-	{
-	    # Handle multi-line bug reporting sections of the form:
-	    #
-	    #   Report <program> bugs to <addr>
-	    #   GNU <package> home page: <url>
-	    #   ...
-	    s/\n([[:upper:]])/\n.br\n$1/g;
-	}
-	elsif ($sect eq _('SEE ALSO'))
-	{
-	    # Handle external references of the form:
-	    #
-	    #   GNU <package> online resources: <addr>
-	    #   Full documentation at: <addr>
-	    #   or available locally via: info ...
-	    #
-	    s/\'/\\(aq/g;			# shell quotes for info command
-	    s/\n(.)/\n.br\n$1/g;		# separate lines for each item
-	}
-    }
-
-    # Check if matched paragraph contains /pat/.
-    if (%append_match)
-    {
-	for my $pat (keys %append_match)
-	{
-	    if ($matched =~ $pat)
-	    {
-		$content .= ".PP\n" unless $append_match{$pat} =~ /^\./;
-		$content .= $append_match{$pat};
-	    }
-	}
-    }
-
-    $include{$sect} .= $content;
-}
-
-# Refer to the real documentation.
-unless ($opt_no_info)
-{
-    my $info_page = $opt_info || $program;
-
-    $sect = _('SEE ALSO');
-    $include{$sect} .= ".PP\n" if $include{$sect};
-    $include{$sect} .= sprintf _(<<'EOT'), $program, $program, $info_page;
-The full documentation for
-.B %s
-is maintained as a Texinfo manual.  If the
-.B info
-and
-.B %s
-programs are properly installed at your site, the command
-.IP
-.B info %s
-.PP
-should give you access to the complete manual.
-EOT
-}
-
-# Append additional text.
-while (my ($sect, $text) = each %append)
-{
-    $include{$sect} .= $append{$sect};
-}
-
-# Replace sections.
-while (my ($sect, $text) = each %replace)
-{
-    $include{$sect} = $replace{$sect};
-}
-
-# Output header.
-print <<EOT;
-.\\" DO NOT MODIFY THIS FILE!  It was generated by $this_program $this_version.
-.TH $PROGRAM "$section" "$date" "$source" "$manual"
-EOT
-
-# Section ordering.
-my @pre = (_('NAME'), _('SYNOPSIS'), _('DESCRIPTION'), _('OPTIONS'),
-    _('EXAMPLES'));
-my @post = (_('ENVIRONMENT'), _('FILES'), _('AUTHOR'),
-    _('REPORTING BUGS'), _('COPYRIGHT'), _('SEE ALSO'));
-my %filter = map { $_ => 1 } @pre, @post;
-
-# Output content.
-my %done;
-for my $sect (@pre, (grep !$filter{$_}, @sections), @post)
-{
-    next if $done{$sect}++;  # ignore duplicates
-    next unless $include{$sect};
-    if ($include{$sect})
-    {
-	my $quote = $sect =~ /\W/ ? '"' : '';
-	print enc ".SH $quote$sect$quote\n";
-
-	for ($include{$sect})
-	{
-            # Add bold style around referenced pages.
-            if ($opt_bold_refs)
-            {
-                # This will ignore entries already marked up (with \)
-                s/(^|\s|,)([\[\w\x83]+)\(([1-9][[:lower:]]?)\)/$1\\fB$2\\fP($3)/g;
-            }
-
-	    # Replace leading dot, apostrophe, backslash and hyphen
-	    # tokens.
-	    s/\x80/\\&./g;
-	    s/\x81/\\&'/g;
-	    s/\x82/\\e/g;
-	    s/\x83/\\-/g;
-
-	    # Convert some latin1 chars to troff equivalents
-	    s/\xa0/\\ /g; # non-breaking space
-
-	    print enc $_;
-	}
-    }
-}
-
-close STDOUT or kark N_("%s: error writing to %s (%s)"), $this_program,
-    $opt_output || 'stdout', $!;
-
-exit;
-
-# Get program basename, and strip libtool "lt-" prefix if required.
-sub program_basename
-{
-    local $_ = shift;
-    s!.*/!!;
-    s/^lt-// if $opt_libtool;
-    $_;
-}
-
-# Call program with given option and return results.
-sub get_option_value
-{
-    my ($prog, $opt) = @_;
-    my $stderr = $discard_stderr ? '/dev/null' : '&1';
-    my $value = join '',
-	map { s/ +$//; expand $_ }
-	map { dec $_ }
-	`$prog $opt 2>$stderr`;
-
-    unless ($value)
-    {
-	my $err = N_("%s: can't get `%s' info from %s%s");
-	my $extra = $discard_stderr
-	    ? "\n" . N_("Try `--no-discard-stderr' if option outputs to stderr")
-	    : '';
-
-	kark $err, $this_program, $opt, $prog, $extra;
-    }
-
-    $value;
-}
-
-# Convert option dashes to \- to stop nroff from hyphenating 'em, and
-# embolden.  Option arguments get italicised.
-sub convert_option
-{
-    local $_ = '\fB' . shift;
-
-    s/-/\x83/g;
-    unless (s/\[=(.*)\]$/\\fR[=\\fI$1\\fR]/)
-    {
-	s/=(.)/\\fR=\\fI$1/;
-	s/ (.)/ \\fI$1/;
-	$_ .= '\fR';
-    }
-
-    $_;
-}
-
-# Insert spacing escape characters \, and \/ before and after italic text.  See
-# https://www.gnu.org/software/groff/manual/html_node/Ligatures-and-Kerning.html
-sub fix_italic_spacing
-{
-    local $_ = shift;
-    s!\\fI(.*?)\\f([BRP])!\\fI\\,$1\\/\\f$2!g;
-    return $_;
-}

po/POTFILES.in

@@ -1,6 +1,6 @@
 # List of files that contain translatable strings.
 
-# Copyright (C) 2001-2002, 2009-2013, 2015-2025 Free Software Foundation, Inc.
+# Copyright (C) 2001-2002, 2009-2013, 2015-2026 Free Software Foundation, Inc.
 
 # This program is free software: you can redistribute it and/or modify
 # it under the terms of the GNU General Public License as published by

po/en.po

@@ -1,30 +0,0 @@
-# English messages for GNU diffutils
-# Copyright 1998, 2001-2003, 2009-2013, 2015-2025 Free Software Foundation,
-# Inc.
-# Paul Eggert <eggert@twinsun.com>, 1998
-#
-msgid ""
-msgstr ""
-"Project-Id-Version: GNU diffutils 3.2\n"
-"POT-Creation-Date: 2002-06-16 23:44-0700\n"
-"PO-Revision-Date: 2012-01-25 23:11-0700\n"
-"Last-Translator: Paul Eggert <eggert@cs.ucla.edu>\n"
-"Language-Team: English <en@translate.freefriends.org>\n"
-"MIME-Version: 1.0\n"
-"Content-Type: text/plain; charset=UTF-8\n"
-"Content-Transfer-Encoding: 8bit\n"
-
-#. TRANSLATORS: Please translate "(C)" to the C-in-a-circle symbol
-#. (U+00A9, COPYRIGHT SIGN) if possible, as this has some minor
-#. technical advantages in international copyright law.  If the
-#. copyright symbol is not available, please leave it as "(C)".
-#: lib/version-etc.c:50
-msgid "(C)"
-msgstr "©"
-
-#. TRANSLATORS: Please translate the second "o" in "Torbjorn Granlund"
-#. to an o-with-umlaut (U+00F6, LATIN SMALL LETTER O WITH DIAERESIS)
-#. if possible.
-#: src/cmp.c:47
-msgid "Written by Torbjorn Granlund and David MacKenzie."
-msgstr "Written by Torbjörn Granlund and David MacKenzie."

src/Makefile.am

@@ -1,6 +1,6 @@
 # Automakefile for GNU diffutils programs.
 
-# Copyright (C) 2001-2002, 2006, 2009-2013, 2015-2025 Free Software Foundation,
+# Copyright (C) 2001-2002, 2006, 2009-2013, 2015-2026 Free Software Foundation,
 # Inc.
 
 # This program is free software: you can redistribute it and/or modify
@@ -47,8 +47,8 @@ diff3_SOURCES = diff3.c system.c
 sdiff_SOURCES = sdiff.c system.c
 diff_SOURCES = \
   analyze.c context.c diff.c dir.c ed.c ifdef.c io.c \
-  normal.c side.c system.c util.c
+  normal.c side.c syncsig.c system.c util.c
-noinst_HEADERS = diff.h system.h
+noinst_HEADERS = diff.h syncsig.h system.h
 
 MOSTLYCLEANFILES = paths.h paths.ht
 

src/analyze.c

@@ -1,7 +1,7 @@
 /* Analyze file differences for GNU DIFF.
 
    Copyright (C) 1988-1989, 1992-1995, 1998, 2001-2002, 2004, 2006-2007,
-   2009-2013, 2015-2025 Free Software Foundation, Inc.
+   2009-2013, 2015-2026 Free Software Foundation, Inc.
 
    This file is part of GNU DIFF.
 

src/cmp.c

@@ -1,7 +1,7 @@
 /* GNU cmp - compare two files byte by byte
 
    Copyright (C) 1990-1996, 1998, 2001-2002, 2004, 2006-2007, 2009-2013,
-   2015-2025 Free Software Foundation, Inc.
+   2015-2026 Free Software Foundation, Inc.
 
    This program is free software: you can redistribute it and/or modify
    it under the terms of the GNU General Public License as published by
@@ -28,7 +28,6 @@
 #include <exitfail.h>
 #include <file-type.h>
 #include <getopt.h>
-#include <hard-locale.h>
 #include <progname.h>
 #include <quote.h>
 #include <unlocked-io.h>
@@ -46,11 +45,15 @@ static char const PROGRAM_NAME[] = "cmp";
   proper_name_lite ("Torbjorn Granlund", "Torbj\303\266rn Granlund"), \
   _("David MacKenzie")
 
+/* Return true if the locale's messages might not be those of C or POSIX.  */
 static bool
 hard_locale_LC_MESSAGES (void)
 {
-#if defined LC_MESSAGES && ENABLE_NLS
+#if ENABLE_NLS
-  return hard_locale (LC_MESSAGES);
+  /* GNU diff defines ENABLE_NLS only if gettext is preinstalled, and
+     on these platforms setlocale (LC_MESSAGES, nullptr) never returns nullptr
+     and always returns "C" when in the C or POSIX locales.  */
+  return !STREQ (setlocale (LC_MESSAGES, nullptr), "C");
 #else
   return false;
 #endif
@@ -208,7 +211,6 @@ main (int argc, char **argv)
   set_program_name (argv[0]);
   setlocale (LC_ALL, "");
   bindtextdomain (PACKAGE, LOCALEDIR);
-  bindtextdomain ("gnulib", GNULIB_LOCALEDIR);
   textdomain (PACKAGE);
   c_stack_action (nullptr);
   xstdopen ();

src/context.c

@@ -1,7 +1,7 @@
 /* Context-format output routines for GNU DIFF.
 
    Copyright (C) 1988-1989, 1991-1995, 1998, 2001-2002, 2004, 2006, 2009-2013,
-   2015-2025 Free Software Foundation, Inc.
+   2015-2026 Free Software Foundation, Inc.
 
    This file is part of GNU DIFF.
 
@@ -72,7 +72,8 @@ print_context_label (char const *mark,
 
       struct tm const *tm = localtime (&ts.tv_sec);
       int nsec = ts.tv_nsec;
-      if (tm && nstrftime (buf, sizeof buf, time_format, tm, localtz, nsec))
+      if (tm
+	  && 0 <= nstrftime (buf, sizeof buf, time_format, tm, localtz, nsec))
 	fprintf (outfile, "%s %s\t%s", mark, name, buf);
       else if (TYPE_SIGNED (time_t))
         {

src/diff.c

@@ -1,7 +1,7 @@
 /* GNU diff - compare files line by line
 
    Copyright (C) 1988-1989, 1992-1994, 1996, 1998, 2001-2002, 2004, 2006-2007,
-   2009-2013, 2015-2025 Free Software Foundation, Inc.
+   2009-2013, 2015-2026 Free Software Foundation, Inc.
 
    This file is part of GNU DIFF.
 
@@ -35,7 +35,7 @@
 #include <filenamecat.h>
 #include <fnmatch.h>
 #include <getopt.h>
-#include <hard-locale.h>
+#include <strftime.h>
 #include <progname.h>
 #include <quote.h>
 #include <sh-quote.h>
@@ -293,6 +293,21 @@ exclude_options (void)
 {
   return EXCLUDE_WILDCARDS | (ignore_file_name_case ? FNM_CASEFOLD : 0);
 }
+
+/* Return true if in a hard LC_TIME locale.  */
+static bool
+hard_locale_LC_TIME (void)
+{
+  /* Use the heuristic that %c has its usual POSIX meaning.
+     This is good enough in practice.  */
+  static struct tm const tm
+    = { .tm_year = 1970 - 1900, .tm_mon = 0, .tm_mday = 1,
+	.tm_hour = 23, .tm_min = 59, .tm_sec = 59 };
+  static char const expected[] = "Thu Jan  1 23:59:59 1970";
+  char buf[sizeof expected];
+  return (nstrftime (buf, sizeof buf, "%c", &tm, 0, 0) == sizeof buf - 1
+	  && memcmp (buf, expected, sizeof buf) == 0);
+}
 
 int
 main (int argc, char **argv)
@@ -303,7 +318,6 @@ main (int argc, char **argv)
   set_program_name (argv[0]);
   setlocale (LC_ALL, "");
   bindtextdomain (PACKAGE, LOCALEDIR);
-  bindtextdomain ("gnulib", GNULIB_LOCALEDIR);
   textdomain (PACKAGE);
   c_stack_action (nullptr);
   function_regexp_list.buf = &function_regexp;
@@ -747,7 +761,7 @@ main (int argc, char **argv)
         specify_style (OUTPUT_NORMAL);
     }
 
-  if (output_style != OUTPUT_CONTEXT || hard_locale (LC_TIME))
+  if (output_style != OUTPUT_CONTEXT || hard_locale_LC_TIME ())
     {
 #if defined STAT_TIMESPEC || defined STAT_TIMESPEC_NS
       time_format = "%Y-%m-%d %H:%M:%S.%N %z";
@@ -966,8 +980,8 @@ check_stdout (void)
 
 static char const *const option_help_msgid[] = {
   N_("    --normal                  output a normal diff (the default)"),
-  N_("-q, --brief                   report only when files differ"),
+  N_("-q, --brief                   report only whether files differ"),
-  N_("-s, --report-identical-files  report when two files are the same"),
+  N_("-s, --report-identical-files  also report if two files are the same"),
   N_("-c, -C NUM, --context[=NUM]   output NUM (default 3) lines of copied context"),
   N_("-u, -U NUM, --unified[=NUM]   output NUM (default 3) lines of unified context"),
   N_("-e, --ed                      output an ed script"),
@@ -1075,11 +1089,10 @@ Mandatory arguments to long options are mandatory for short options too.\n\
 
   for (char const *const *p = option_help_msgid;  *p;  p++)
     {
-      if (!**p)
+      char const *msg = *p;
-        putchar ('\n');
+      if (*msg)
-      else
         {
-          char const *msg = _(*p);
+	  msg = gettext (msg);
 	  for (char const *nl; (nl = strchr (msg, '\n')); msg = nl + 1)
             {
 	      fputs ("  ", stdout);
@@ -1088,8 +1101,8 @@ Mandatory arguments to long options are mandatory for short options too.\n\
 
 	  if (*msg == ' ' || *msg == '-')
 	    fputs ("  ", stdout);
-	  puts (msg);
         }
+      puts (msg);
     }
   emit_bug_reporting_address ();
 }

src/diff.h

@@ -1,7 +1,7 @@
 /* Shared definitions for GNU DIFF
 
    Copyright (C) 1988-1989, 1991-1995, 1998, 2001-2002, 2004, 2009-2013,
-   2015-2025 Free Software Foundation, Inc.
+   2015-2026 Free Software Foundation, Inc.
 
    This file is part of GNU DIFF.
 

src/diff3.c

@@ -1,7 +1,7 @@
 /* GNU diff3 - compare three files line by line
 
    Copyright (C) 1988-1989, 1992-1996, 1998, 2001-2002, 2004, 2006, 2009-2013,
-   2015-2025 Free Software Foundation, Inc.
+   2015-2026 Free Software Foundation, Inc.
 
    This program is free software: you can redistribute it and/or modify
    it under the terms of the GNU General Public License as published by
@@ -233,7 +233,6 @@ main (int argc, char **argv)
   set_program_name (argv[0]);
   setlocale (LC_ALL, "");
   bindtextdomain (PACKAGE, LOCALEDIR);
-  bindtextdomain ("gnulib", GNULIB_LOCALEDIR);
   textdomain (PACKAGE);
   c_stack_action (nullptr);
   xstdopen ();

src/dir.c

@@ -1,7 +1,7 @@
 /* Read, sort and compare two directories.  Used for GNU DIFF.
 
    Copyright (C) 1988-1989, 1992-1995, 1998, 2001-2002, 2004, 2006-2007,
-   2009-2013, 2015-2025 Free Software Foundation, Inc.
+   2009-2013, 2015-2026 Free Software Foundation, Inc.
 
    This file is part of GNU DIFF.
 

src/ed.c

@@ -1,7 +1,7 @@
 /* Output routines for ed-script format.
 
    Copyright (C) 1988-1989, 1991-1993, 1995, 1998, 2001, 2004, 2006, 2009-2013,
-   2015-2025 Free Software Foundation, Inc.
+   2015-2026 Free Software Foundation, Inc.
 
    This file is part of GNU DIFF.
 

src/ifdef.c

@@ -1,6 +1,6 @@
 /* #ifdef-format output routines for GNU DIFF.
 
-   Copyright (C) 1989, 1991-1994, 2001-2002, 2004, 2006, 2009-2013, 2015-2025
+   Copyright (C) 1989, 1991-1994, 2001-2002, 2004, 2006, 2009-2013, 2015-2026
    Free Software Foundation, Inc.
 
    This file is part of GNU DIFF.

src/io.c

@@ -1,7 +1,7 @@
 /* File I/O for GNU DIFF.
 
    Copyright (C) 1988-1989, 1992-1995, 1998, 2001-2002, 2004, 2006, 2009-2013,
-   2015-2025 Free Software Foundation, Inc.
+   2015-2026 Free Software Foundation, Inc.
 
    This file is part of GNU DIFF.
 

src/normal.c

@@ -1,6 +1,6 @@
 /* Normal-format output routines for GNU DIFF.
 
-   Copyright (C) 1988-1989, 1993, 1995, 1998, 2001, 2006, 2009-2013, 2015-2025
+   Copyright (C) 1988-1989, 1993, 1995, 1998, 2001, 2006, 2009-2013, 2015-2026
    Free Software Foundation, Inc.
 
    This file is part of GNU DIFF.

src/sdiff.c

@@ -1,7 +1,7 @@
 /* GNU sdiff - side-by-side merge of file differences
 
    Copyright (C) 1992-1996, 1998, 2001-2002, 2004, 2006-2007, 2009-2013,
-   2015-2025 Free Software Foundation, Inc.
+   2015-2026 Free Software Foundation, Inc.
 
    This file is part of GNU DIFF.
 
@@ -100,7 +100,9 @@ enum
 typedef void (*sighandler) (int);
 static void signal_handler (int, sighandler);
 
-#if HAVE_SIGACTION
+/* Use SA_NOCLDSTOP as a proxy for whether the sigaction machinery is
+   present.  */
+#ifdef SA_NOCLDSTOP
 /* Prefer 'sigaction' if available, since 'signal' can lose signals.  */
 static struct sigaction initial_action[NUM_SIGS];
 static sighandler
@@ -449,7 +451,6 @@ main (int argc, char *argv[])
   set_program_name (argv[0]);
   setlocale (LC_ALL, "");
   bindtextdomain (PACKAGE, LOCALEDIR);
-  bindtextdomain ("gnulib", GNULIB_LOCALEDIR);
   textdomain (PACKAGE);
   c_stack_action (cleanup);
   xstdopen ();
@@ -715,21 +716,21 @@ static bool sigs_trapped;
 static void
 catchsig (int s)
 {
-#if ! HAVE_SIGACTION
+#ifndef SA_NOCLDSTOP
   signal (s, SIG_IGN);
 #endif
   if (! (s == SIGINT && ignore_SIGINT))
     signal_received = s;
 }
 
-#if HAVE_SIGACTION
+#ifdef SA_NOCLDSTOP
 static struct sigaction catchaction;
 #endif
 
 static void
 signal_handler (int sig, sighandler handler)
 {
-#if HAVE_SIGACTION
+#ifdef SA_NOCLDSTOP
   catchaction.sa_handler = handler;
   sigaction (sig, &catchaction, 0);
 #else
@@ -740,7 +741,7 @@ signal_handler (int sig, sighandler handler)
 static void
 trapsigs (void)
 {
-#if HAVE_SIGACTION
+#ifdef SA_NOCLDSTOP
   catchaction.sa_flags = SA_RESTART;
   sigemptyset (&catchaction.sa_mask);
   for (int i = 0;  i < NUM_SIGS;  i++)
@@ -749,7 +750,7 @@ trapsigs (void)
 
   for (int i = 0;  i < NUM_SIGS;  i++)
     {
-#if HAVE_SIGACTION
+#ifdef SA_NOCLDSTOP
       sigaction (sigs[i], nullptr, &initial_action[i]);
 #else
       initial_action[i] = signal (sigs[i], SIG_IGN);
@@ -774,7 +775,7 @@ untrapsig (int s)
     for (int i = 0;  i < NUM_SIGS;  i++)
       if ((! s || sigs[i] == s)  &&  initial_handler (i) != SIG_IGN)
         {
-#if HAVE_SIGACTION
+#ifdef SA_NOCLDSTOP
           sigaction (sigs[i], &initial_action[i], nullptr);
 #else
           signal (sigs[i], initial_action[i]);
@@ -803,7 +804,7 @@ checksigs (void)
 static void
 give_help (void)
 {
-  fprintf (stderr, "%s", _("\
+  fputs (_("\
 ed:\tEdit then use both versions, each decorated with a header.\n\
 eb:\tEdit then use both versions.\n\
 el or e1:\tEdit then use the left version.\n\
@@ -814,20 +815,15 @@ r or 2:\tUse the right version.\n\
 s:\tSilently include common lines.\n\
 v:\tVerbosely include common lines.\n\
 q:\tQuit.\n\
-"));
+"), stderr);
 }
 
 static int
 skip_white (void)
 {
   int c;
-  for (;;)
+  while ((c = getchar ()) != '\n' && c_isspace (c))
-    {
+    checksigs ();
-      c = getchar ();
-      if (! c_isspace (c) || c == '\n')
-        break;
-      checksigs ();
-    }
   if (ferror (stdin))
     perror_fatal (_("read failed"));
   return c;
@@ -857,8 +853,7 @@ edit (struct line_filter *left, char const *lname, lin lline, lin llen,
 {
   for (;;)
     {
-      int cmd0;
+      int cmd;
-      int cmd1;
       bool gotcmd = false;
 
       while (! gotcmd)
@@ -867,48 +862,41 @@ edit (struct line_filter *left, char const *lname, lin lline, lin llen,
             perror_fatal (_("write failed"));
           ck_fflush (stdout);
 
-          cmd0 = skip_white ();
+	  cmd = skip_white ();
-          switch (cmd0)
+          switch (cmd)
             {
-            case '1': case '2': case 'l': case 'r':
+	    case 'e':;
-            case 's': case 'v': case 'q':
+	      int cmd1 = skip_white ();
-              if (skip_white () != '\n')
-                {
-                  give_help ();
-                  flush_line ();
-                  continue;
-                }
-              gotcmd = true;
-              break;
-
-            case 'e':
-              cmd1 = skip_white ();
               switch (cmd1)
                 {
-                case '1': case '2': case 'b': case 'd': case 'l': case 'r':
-                  if (skip_white () != '\n')
-                    {
-                      give_help ();
-                      flush_line ();
-                      continue;
-                    }
-                  gotcmd = true;
-                  break;
                 case '\n':
                   gotcmd = true;
-                  break;
+		  continue;
                 default:
                   give_help ();
                   flush_line ();
-                  continue;
+		  continue;
+		case '1': case '2': case 'b': case 'd': case 'l': case 'r':
+		  cmd |= cmd1 << UCHAR_WIDTH;
+		  break;
                 }
+	      FALLTHROUGH;
+	    case '1': case '2': case 'l': case 'r':
+	    case 's': case 'v': case 'q':
+	      if (skip_white () == '\n')
+		gotcmd = true;
+	      else
+		{
+		  give_help ();
+		  flush_line ();
+		}
               break;
 
             case EOF:
               if (feof (stdin))
                 {
                   gotcmd = true;
-                  cmd0 = 'q';
+                  cmd = 'q';
                   break;
                 }
               FALLTHROUGH;
@@ -917,11 +905,11 @@ edit (struct line_filter *left, char const *lname, lin lline, lin llen,
               FALLTHROUGH;
             case '\n':
               give_help ();
-              continue;
+	      break;
             }
         }
 
-      switch (cmd0)
+      switch (cmd & UCHAR_MAX)
         {
         case '1': case 'l':
           lf_copy (left, llen, outfile);
@@ -954,6 +942,7 @@ edit (struct line_filter *left, char const *lname, lin lline, lin llen,
           if (! tmp)
 	    perror_fatal (squote (0, tmpname));
 
+	  int cmd1 = cmd >> UCHAR_WIDTH;
           switch (cmd1)
             {
             case 'd':

src/side.c

@@ -1,6 +1,6 @@
 /* sdiff-format output routines for GNU DIFF.
 
-   Copyright (C) 1991-1993, 1998, 2001-2002, 2004, 2009-2013, 2015-2025 Free
+   Copyright (C) 1991-1993, 1998, 2001-2002, 2004, 2009-2013, 2015-2026 Free
    Software Foundation, Inc.
 
    This file is part of GNU DIFF.

src/syncsig.c

@@ -0,0 +1,350 @@
+/* Synchronous signal handling
+
+   Copyright 2025-2026 Free Software Foundation, Inc.
+
+   This file is part of GNU DIFF.
+
+   This program is free software: you can redistribute it and/or modify
+   it under the terms of the GNU General Public License as published by
+   the Free Software Foundation, either version 3 of the License, or
+   (at your option) any later version.
+
+   This program is distributed in the hope that it will be useful,
+   but WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+   GNU General Public License for more details.
+
+   You should have received a copy of the GNU General Public License
+   along with this program.  If not, see <http://www.gnu.org/licenses/>.  */
+
+#include <config.h>
+
+#include "syncsig.h"
+
+#include "minmax.h"
+
+#include <signal.h>
+#include <stdcountof.h>
+
+/* Use SA_NOCLDSTOP as a proxy for whether the sigaction machinery is
+   present.  */
+#ifndef SA_NOCLDSTOP
+# define SA_NOCLDSTOP 0
+# define sigprocmask(how, set, oset) 0
+# if ! HAVE_SIGINTERRUPT
+#  define siginterrupt(sig, flag) 0
+# endif
+#endif
+
+#ifndef SA_RESTART
+# define SA_RESTART 0
+#endif
+#ifndef SIGSTOP
+# define SIGSTOP 0
+#endif
+
+/* The set of signals that are caught.  */
+static sigset_t caught_signals;
+
+/* The signals we can catch.
+   This includes all catchable GNU/Linux or POSIX signals that by
+   default are ignored, or that stop or terminate the process.
+   It also includes SIGQUIT since that can come from the terminal.
+   It excludes other signals that normally come from program failure.
+   If you modify this table, also modify signal_count's initializer.  */
+static int const catchable[] =
+  {
+    /* SIGABRT is normally from program failure.  */
+    SIGALRM,
+    /* SIGBUS is normally from program failure.  */
+#ifdef SIGCHLD
+    SIGCHLD,
+#else
+# define SIGCHLD 0
+#endif
+    /* SIGCLD (older platforms) is an alias for SIGCHLD.  */
+#ifdef SIGCONT
+    SIGCONT,
+#else
+# define SIGCONT 0
+#endif
+    /* SIGEMT is normally from program failure.  */
+    /* SIGFPE is normally from program failure.  */
+    SIGHUP,
+    /* SIGILL is normally from program failure.  */
+    /* SIGINFO is an alias for SIGPWR on Linux.  */
+    SIGINT,
+    /* SIGIO is an alias for SIGPOLL.  */
+    /* SIGKILL can't be caught.  */
+#ifdef SIGLOST
+    SIGLOST,
+#else
+# define SIGLOST 0
+#endif
+    SIGPIPE,
+#ifdef SIGPOLL /* Removed from POSIX.1-2024; still in Linux.  */
+    SIGPOLL,
+#else
+# define SIGPOLL 0
+#endif
+#ifdef SIGPROF /* Removed from POSIX.1-2024; still in Linux.  */
+    SIGPROF,
+#else
+# define SIGPROF 0
+#endif
+#ifdef SIGPWR
+    SIGPWR,
+#else
+# define SIGPWR 0
+#endif
+    SIGQUIT,
+    /* SIGSEGV is normally from program failure.  */
+    /* Linux SIGSTKFLT is unused.  */
+    /* SIGSTOP can't be caught.  */
+    /* SIGSYS is normally from program failure.  */
+    SIGTERM,
+    /* SIGTRAP is normally from program failure.  */
+#ifdef SIGTSTP
+    SIGTSTP,
+#else
+# define SIGTSTP 0
+#endif
+#ifdef SIGTTIN
+    SIGTTIN,
+#else
+# define SIGTTIN 0
+#endif
+#ifdef SIGTTOU
+    SIGTTOU,
+#else
+# define SIGTTOU 0
+#endif
+#ifdef SIGURG
+    SIGURG,
+#else
+# define SIGURG 0
+#endif
+#ifdef SIGUSR1
+    SIGUSR1,
+#else
+# define SIGUSR1 0
+#endif
+#ifdef SIGUSR2
+    SIGUSR2,
+#else
+# define SIGUSR2 0
+#endif
+#ifdef SIGVTALRM
+    SIGVTALRM,
+#else
+# define SIGVTALRM 0
+#endif
+#ifdef SIGWINCH
+    SIGWINCH,
+#else
+# define SIGWINCH 0
+#endif
+#ifdef SIGXCPU
+    SIGXCPU,
+#else
+# define SIGXCPU 0
+#endif
+#ifdef SIGXFSZ
+    SIGXFSZ,
+#else
+# define SIGXFSZ 0
+#endif
+  };
+
+/* Number of pending signals received, for each signal type.  */
+static sig_atomic_t volatile signal_count[] =
+  {
+    /* Explicitly initialize, so that the table is large enough.  */
+    [SIGALRM] = 0,
+    [SIGCHLD] = 0,
+    [SIGCONT] = 0,
+    [SIGHUP] = 0,
+    [SIGINT] = 0,
+    [SIGLOST] = 0,
+    [SIGPIPE] = 0,
+    [SIGPOLL] = 0,
+    [SIGPROF] = 0,
+    [SIGPWR] = 0,
+    [SIGQUIT] = 0,
+    [SIGTERM] = 0,
+    [SIGTSTP] = 0,
+    [SIGTTIN] = 0,
+    [SIGTTOU] = 0,
+    [SIGURG] = 0,
+    [SIGUSR1] = 0,
+    [SIGUSR2] = 0,
+    [SIGVTALRM] = 0,
+    [SIGWINCH] = 0,
+    [SIGXCPU] = 0,
+    [SIGXFSZ] = 0,
+  };
+
+/* This acts as bool though its type is sig_atomic_t.
+   If true, signal_count might contain nonzero entries.
+   If false, signal_count is all zero.
+   This is to speed up syncsig_poll when it returns 0.  */
+static sig_atomic_t volatile possible_signal_count;
+
+/* Actions before syncsig_install was called.  */
+#if SA_NOCLDSTOP
+static struct sigaction oldact[countof (signal_count)];
+#else
+static void (*oldact[countof (signal_count)]) (int);
+#endif
+
+/* Record an asynchronous signal.  This function is async-signal-safe.  */
+static void
+sighandler (int sig)
+{
+#if !SA_NOCLDSTOP
+  /* An unavoidable race here: the default action might mistakenly
+     be taken before 'signal' is called.  */
+  signal (sig, sighandler);
+#endif
+
+  possible_signal_count = true;
+  signal_count[sig]++;
+}
+
+void
+syncsig_install (int flags)
+{
+  for (int i = 0; i < countof (catchable); i++)
+    signal_count[catchable[i]] = 0;
+  possible_signal_count = false;
+
+  sigemptyset (&caught_signals);
+
+  for (int i = 0; i < countof (catchable); i++)
+    {
+      int sig = catchable[i];
+
+      if (((sig == SIGTSTP) & !(flags & SYNCSIG_TSTP))
+	  | ((sig == SIGTTIN) & !(flags & SYNCSIG_TTIN))
+	  | ((sig == SIGTTOU) & !(flags & SYNCSIG_TTOU)))
+	continue;
+
+#if SA_NOCLDSTOP
+      sigaction (sig, nullptr, &oldact[sig]);
+      bool catching_sig = oldact[sig].sa_handler != SIG_IGN;
+#else
+      oldact[i] = signal (sig, SIG_IGN);
+      bool catching_sig = oldact[i] != SIG_IGN;
+      if (catching_sig)
+	{
+	  /* An unavoidable race here: SIG might be mistakenly ignored
+	     before 'signal' is called.  */
+	  signal (sig, sighandler);
+	  siginterrupt (sig, 0);
+	}
+#endif
+      if (catching_sig)
+	sigaddset (&caught_signals, sig);
+    }
+
+#if SA_NOCLDSTOP
+  struct sigaction act;
+  act.sa_handler = sighandler;
+  act.sa_mask = caught_signals;
+  act.sa_flags = SA_RESTART;
+
+  for (int i = 0; i < countof (catchable); i++)
+    {
+      int sig = catchable[i];
+      if (sigismember (&caught_signals, sig))
+	sigaction (sig, &act, nullptr);
+    }
+#endif
+}
+
+void
+syncsig_uninstall (void)
+{
+  for (int i = 0; i < countof (catchable); i++)
+    {
+      int sig = catchable[i];
+      if (sigismember (&caught_signals, sig))
+	{
+#if SA_NOCLDSTOP
+	  sigaction (sig, &oldact[sig], nullptr);
+#else
+	  signal (sig, oldact[sig]);
+#endif
+	}
+    }
+}
+
+int
+syncsig_poll (void)
+{
+  int sig = 0;
+
+  if (possible_signal_count)
+    {
+      /* This module uses static rather than thread-local storage,
+	 so it is useful only in single-threaded programs,
+	 and it uses sigprocmask rather than pthread_sigmask.  */
+      sigset_t oldset;
+      sigprocmask (SIG_BLOCK, &caught_signals, &oldset);
+
+      for (int i = 0; ; i++)
+	{
+	  if (i == countof (catchable))
+	    {
+	      possible_signal_count = false;
+	      break;
+	    }
+	  int s = catchable[i];
+	  int c = signal_count[s];
+	  if (c)
+	    {
+	      signal_count[s] = c - 1;
+	      sig = s;
+	      break;
+	    }
+	}
+
+      sigprocmask (SIG_SETMASK, &oldset, nullptr);
+    }
+
+  return sig;
+}
+
+void
+syncsig_deliver (int sig)
+{
+#if SA_NOCLDSTOP
+  struct sigaction act;
+#else
+  void (*act) (int);
+#endif
+
+  if (sig == SIGTSTP)
+    sig = SIGSTOP;
+  else
+    {
+#if SA_NOCLDSTOP
+      sigaction (sig, &oldact[sig], &act);
+#else
+      act = signal (sig, oldact[sig]);
+#endif
+
+    }
+
+  raise (sig);
+
+  if (sig != SIGSTOP)
+    {
+      /* The program did not exit due to the raised signal, so continue.  */
+#if SA_NOCLDSTOP
+      sigaction (sig, &act, nullptr);
+#else
+      signal (sig, act);
+#endif
+    }
+}

src/syncsig.h

@@ -0,0 +1,60 @@
+/* Synchronous signal handling
+
+   Copyright 2025-2026 Free Software Foundation, Inc.
+
+   This file is part of GNU DIFF.
+
+   This program is free software: you can redistribute it and/or modify
+   it under the terms of the GNU General Public License as published by
+   the Free Software Foundation, either version 3 of the License, or
+   (at your option) any later version.
+
+   This program is distributed in the hope that it will be useful,
+   but WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+   GNU General Public License for more details.
+
+   You should have received a copy of the GNU General Public License
+   along with this program.  If not, see <http://www.gnu.org/licenses/>.  */
+
+/* Written by Paul Eggert.  */
+
+/* Flags for syncsig_install.  */
+enum
+  {
+    /* Also catch SIGTSTP, SIGTTIN, SIGTTOU, which by default stop the process.
+       These flags have no effect on platforms lacking these signals.  */
+    SYNCSIG_TSTP = (1 << 0),
+    SYNCSIG_TTIN = (1 << 1),
+    SYNCSIG_TTOU = (1 << 2),
+  };
+
+/* Set up asynchronous signal handling according to FLAGS.
+   syncsig_install fails only on unusual platforms where
+   valid calls to functions like sigaction can fail;
+   if it fails, signal handling is in a weird state
+   and neither syncsig_process nor syncsig_uninstall should be called.  */
+extern void syncsig_install (int flags);
+
+/* Return a signal number if a signal has arrived, zero otherwise.
+   After syncsig_install, there should not be an unbounded amount of
+   time between calls to this function, and its result should be dealt
+   with promptly.  */
+extern int syncsig_poll (void);
+
+/* Do the action for SIG that would have been done
+   had syncsig_install not been called.
+   SIG should have recently been returned by syncsig_poll.
+
+   For example, if SIG is SIGTSTP stop the process and return after
+   SIGCONT is delivered.  Another example: kill the process if SIG is
+   SIGINT and SIGINT handling is the default.
+
+   This function should be called only after syncsig_install.  */
+extern void syncsig_deliver (int sig);
+
+/* Stop doing asynchronous signal handling, undoing syncsig_install.
+   This function should be called only after syncsig_install.
+   To deal with signals arriving just before calling this function,
+   call syncsig_poll afterwards.  */
+extern void syncsig_uninstall (void);

src/system.c

@@ -1,7 +1,7 @@
 /* System dependent declarations.
 
    Copyright (C) 1988-1989, 1992-1995, 1998, 2001-2002, 2004, 2006, 2009-2013,
-   2015-2025 Free Software Foundation, Inc.
+   2015-2026 Free Software Foundation, Inc.
 
    This file is part of GNU DIFF.
 

src/system.h

@@ -1,7 +1,7 @@
 /* System dependent declarations.
 
    Copyright (C) 1988-1989, 1992-1995, 1998, 2001-2002, 2004, 2006, 2009-2013,
-   2015-2025 Free Software Foundation, Inc.
+   2015-2026 Free Software Foundation, Inc.
 
    This file is part of GNU DIFF.
 

src/util.c

@@ -1,7 +1,7 @@
 /* Support routines for GNU DIFF.
 
    Copyright (C) 1988-1989, 1992-1995, 1998, 2001-2002, 2004, 2006, 2009-2013,
-   2015-2025 Free Software Foundation, Inc.
+   2015-2026 Free Software Foundation, Inc.
 
    This file is part of GNU DIFF.
 
@@ -27,31 +27,11 @@
 #include <flexmember.h>
 #include <mcel.h>
 #include <quotearg.h>
+#include <syncsig.h>
 #include <system-quote.h>
 #include <xalloc.h>
 
 #include <stdarg.h>
-#include <signal.h>
-
-/* Use SA_NOCLDSTOP as a proxy for whether the sigaction machinery is
-   present.  */
-#ifndef SA_NOCLDSTOP
-# define SA_NOCLDSTOP 0
-# define sigprocmask(How, Set, Oset) 0
-# if ! HAVE_SIGINTERRUPT
-#  define siginterrupt(sig, flag) 0
-# endif
-#endif
-
-#ifndef SA_RESTART
-# define SA_RESTART 0
-#endif
-#ifndef SIGSTOP
-# define SIGSTOP 0
-#endif
-#ifndef SIGTSTP
-# define SIGTSTP 0
-#endif
 
 char const pr_program[] = PR_PROGRAM;
 
@@ -184,78 +164,9 @@ print_message_queue (void)
       m = next;
     }
 }
-
+
 /* Signal handling, needed for restoring default colors.  */
 
-static void
-xsigaddset (sigset_t *set, int sig)
-{
-  if (sigaddset (set, sig) != 0)
-    pfatal_with_name ("sigaddset");
-}
-
-static bool
-xsigismember (sigset_t const *set, int sig)
-{
-  int mem = sigismember (set, sig);
-  if (mem < 0)
-    pfatal_with_name ("sigismember");
-  assume (mem <= 1);
-  return mem;
-}
-
-typedef void (*signal_handler) (int);
-static signal_handler
-xsignal (int sig, signal_handler func)
-{
-  signal_handler h = signal (sig, func);
-  if (h == SIG_ERR)
-    pfatal_with_name ("signal");
-  return h;
-}
-
-static void
-xsigprocmask (int how, sigset_t const *restrict set, sigset_t *restrict oset)
-{
-  if (sigprocmask (how, set, oset) != 0)
-    pfatal_with_name ("sigprocmask");
-}
-
-/* If true, some signals are caught.  This is separate from
-   'caught_signals' because POSIX doesn't require an all-zero sigset_t
-   to be valid.  */
-static bool some_signals_caught;
-
-/* The set of signals that are caught.  */
-static sigset_t caught_signals;
-
-/* If nonzero, the value of the pending fatal signal.  */
-static sig_atomic_t volatile interrupt_signal;
-
-/* A count of the number of pending stop signals that have been received.  */
-static sig_atomic_t volatile stop_signal_count;
-
-/* An ordinary signal was received; arrange for the program to exit.  */
-
-static void
-sighandler (int sig)
-{
-  if (! SA_NOCLDSTOP)
-    signal (sig, SIG_IGN);
-  if (! interrupt_signal)
-    interrupt_signal = sig;
-}
-
-/* A SIGTSTP was received; arrange for the program to suspend itself.  */
-
-static void
-stophandler (int sig)
-{
-  if (! SA_NOCLDSTOP)
-    signal (sig, stophandler);
-  if (! interrupt_signal)
-    stop_signal_count++;
-}
 /* Process any pending signals.  If signals are caught, this function
    should be called periodically.  Ideally there should never be an
    unbounded amount of time when signals are not being processed.
@@ -265,131 +176,18 @@ stophandler (int sig)
 static void
 process_signals (void)
 {
-  while (interrupt_signal | stop_signal_count)
+  for (int sig; (sig = syncsig_poll ()); )
     {
       set_color_context (RESET_CONTEXT);
       fflush (stdout);
-
+      syncsig_deliver (sig);
-      sigset_t oldset;
-      xsigprocmask (SIG_BLOCK, &caught_signals, &oldset);
-
-      /* Reload stop_signal_count and (if needed) interrupt_signal, in
-	 case a new signal was handled before sigprocmask took effect.  */
-      int stops = stop_signal_count, sig;
-
-      /* SIGTSTP is special, since the application can receive that signal
-         more than once.  In this case, don't set the signal handler to the
-         default.  Instead, just raise the uncatchable SIGSTOP.  */
-      if (stops)
-        {
-          stop_signal_count = stops - 1;
-          sig = SIGSTOP;
-        }
-      else
-	{
-	  sig = interrupt_signal;
-	  xsignal (sig, SIG_DFL);
-	}
-
-      /* Exit or suspend the program.  */
-      if (raise (sig) != 0)
-	pfatal_with_name ("raise");
-      xsigprocmask (SIG_SETMASK, &oldset, nullptr);
-
-      /* If execution reaches here, then the program has been
-         continued (after being suspended).  */
     }
 }
 
-/* The signals that can be caught, the number of such signals,
-   and which of them are actually caught.  */
-static int const sig[] =
-  {
-#if SIGTSTP
-    /* This one is handled specially; see is_tstp_index.  */
-    SIGTSTP,
-#endif
-
-    /* The usual suspects.  */
-#ifdef SIGALRM
-    SIGALRM,
-#endif
-#ifdef SIGHUP
-    SIGHUP,
-#endif
-    SIGINT,
-#ifdef SIGPIPE
-    SIGPIPE,
-#endif
-#ifdef SIGQUIT
-    SIGQUIT,
-#endif
-    SIGTERM,
-#ifdef SIGPOLL
-    SIGPOLL,
-#endif
-#ifdef SIGPROF
-    SIGPROF,
-#endif
-#ifdef SIGVTALRM
-    SIGVTALRM,
-#endif
-#ifdef SIGXCPU
-    SIGXCPU,
-#endif
-#ifdef SIGXFSZ
-    SIGXFSZ,
-#endif
-  };
-enum { nsigs = sizeof (sig) / sizeof *(sig) };
-
-/* True if sig[j] == SIGTSTP.  */
-static bool
-is_tstp_index (int j)
-{
-  return SIGTSTP && j == 0;
-}
-
 static void
 install_signal_handlers (void)
 {
-  if (sigemptyset (&caught_signals) != 0)
+  syncsig_install (SYNCSIG_TSTP);
-    pfatal_with_name ("sigemptyset");
-
-#if SA_NOCLDSTOP
-  for (int j = 0; j < nsigs; j++)
-    {
-      struct sigaction actj;
-      if (sigaction (sig[j], nullptr, &actj) == 0 && actj.sa_handler != SIG_IGN)
-	xsigaddset (&caught_signals, sig[j]);
-    }
-
-  struct sigaction act;
-  act.sa_mask = caught_signals;
-  act.sa_flags = SA_RESTART;
-
-  for (int j = 0; j < nsigs; j++)
-    if (xsigismember (&caught_signals, sig[j]))
-      {
-	act.sa_handler = is_tstp_index (j) ? stophandler : sighandler;
-	if (sigaction (sig[j], &act, nullptr) != 0)
-	  pfatal_with_name ("sigaction");
-	some_signals_caught = true;
-      }
-#else
-  for (int j = 0; j < nsigs; j++)
-    {
-      signal_handler h = signal (sig[j], SIG_IGN);
-      if (h != SIG_IGN && h != SIG_ERR)
-	{
-	  xsigaddset (&caught_signals, sig[j]);
-	  xsignal (sig[j], is_tstp_index (j) ? stophandler : sighandler);
-	  some_signals_caught = true;
-	  if (siginterrupt (sig[j], 0) != 0)
-	    pfatal_with_name ("siginterrupt");
-	}
-    }
-#endif
 }
 
 /* Clean up signal handlers just before exiting the program.  Do this
@@ -398,14 +196,11 @@ install_signal_handlers (void)
 void
 cleanup_signal_handlers (void)
 {
-  if (some_signals_caught)
+  syncsig_uninstall ();
-    {
+  process_signals ();
-      for (int j = 0; j < nsigs; j++)
-	if (xsigismember (&caught_signals, sig[j]))
-	  xsignal (sig[j], SIG_DFL);
-      process_signals ();
-    }
 }
+
+/* Color handling.  */
 
 static char const *current_name[2];
 static bool currently_recursive;

tests/cmp

@@ -1,7 +1,7 @@
 #!/bin/sh
 # Test 'cmp'.
 
-# Copyright 2017-2025 Free Software Foundation, Inc.
+# Copyright 2017-2026 Free Software Foundation, Inc.
 
 # This program is free software: you can redistribute it and/or modify
 # it under the terms of the GNU General Public License as published by

tests/envvar-check

@@ -1,7 +1,7 @@
 # -*- sh -*-
 # Check environment variables for sane values while testing.
 
-# Copyright (C) 2000-2025 Free Software Foundation, Inc.
+# Copyright (C) 2000-2026 Free Software Foundation, Inc.
 
 # This program is free software: you can redistribute it and/or modify
 # it under the terms of the GNU General Public License as published by

tests/help-version

@@ -2,7 +2,7 @@
 # Make sure all these programs work properly
 # when invoked with --help or --version.
 
-# Copyright (C) 2000-2013, 2015-2025 Free Software Foundation, Inc.
+# Copyright (C) 2000-2013, 2015-2026 Free Software Foundation, Inc.
 
 # This program is free software: you can redistribute it and/or modify
 # it under the terms of the GNU General Public License as published by

tests/init.cfg

@@ -1,6 +1,6 @@
 # This file is sourced by init.sh, *before* its initialization.
 
-# Copyright (C) 2010-2025 Free Software Foundation, Inc.
+# Copyright (C) 2010-2026 Free Software Foundation, Inc.
 
 # This program is free software: you can redistribute it and/or modify
 # it under the terms of the GNU General Public License as published by