acinclude.m4

# ===========================================================================
#   https://www.gnu.org/software/autoconf-archive/ax_func_getopt_long.html
# ===========================================================================
#
# SYNOPSIS
#
#   AX_FUNC_GETOPT_LONG
#
# DESCRIPTION
#
#   Check for getopt_long support.
#
#   This assume that the standard getopt.h file (from GNU libc) is available
#   as lib/gnugetopt.h. If needed, this file will be linked as getopt.h, but
#   we want to default to the system's getopt.h file. (See
#   http://sources.redhat.com/ml/automake/2000-09/msg00041.html for an
#   explanation about why using the system's getopt.h file is important.)
#
# LICENSE
#
#   Copyright (c) 2008 Alexandre Duret-Lutz <adl@gnu.org>
#
#   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 2 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 <https://www.gnu.org/licenses/>.
#
#   As a special exception, the respective Autoconf Macro's copyright owner
#   gives unlimited permission to copy, distribute and modify the configure
#   scripts that are the output of Autoconf when processing the Macro. You
#   need not follow the terms of the GNU General Public License when using
#   or distributing such scripts, even though portions of the text of the
#   Macro appear in them. The GNU General Public License (GPL) does govern
#   all other use of the material that constitutes the Autoconf Macro.
#
#   This special exception to the GPL applies to versions of the Autoconf
#   Macro released by the Autoconf Archive. When you make and distribute a
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#   exception to the GPL to apply to your modified version as well.

#serial 6

AU_ALIAS([ADL_FUNC_GETOPT_LONG], [AX_FUNC_GETOPT_LONG])
AC_DEFUN([AX_FUNC_GETOPT_LONG],
 [AC_PREREQ(2.49)dnl
  # clean out junk possibly left behind by a previous configuration
  rm -f lib/getopt.h
  # Check for getopt_long support
  AC_CHECK_HEADERS([getopt.h])
  AC_CHECK_FUNCS([getopt_long],,
   [# FreeBSD has a gnugetopt library for this
    AC_CHECK_LIB([gnugetopt],[getopt_long],[AC_DEFINE([HAVE_GETOPT_LONG])],
     [# use the GNU replacement
      AC_LIBOBJ(getopt)
      AC_LIBOBJ(getopt1)
      AC_CONFIG_LINKS([src/getopt.h:src/gnugetopt.h])])])])