dnl -*-autoconf-*-

### SYNOPSIS
###
###   mdw_DECL_ENVIRON
###
### DESCRIPTION
###
###   Define a preprocessor symbol `DECL_ENVIRON' if the `environ' vector is
###   declared in one of the `usual' places.
###
### LICENSE
###
###   Copyright (c) 1999 Mark Wooding <mdw@distorted.org.uk>
###
###   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 <http://www.gnu.org/licenses/>.
###
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###
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# serial 1
AC_DEFUN([mdw_DECL_ENVIRON],
[AC_CACHE_CHECK([for declaration of \`environ'], mdw_cv_environ,
[AC_EGREP_CPP([\<environ\>],
[#include <sys/types.h>
#if HAVE_UNISTD_H
#include <unistd.h>
#endif
#if STDC_HEADERS
#include <stdlib.h>
#include <stddef.h>
#endif], [mdw_cv_environ=yes], [mdw_cv_environ=no])])
if test $mdw_cv_environ = yes; then
  AC_DEFINE([DECL_ENVIRON], [1],
	    [Define if you have the `environ' vector of environment variables.])
fi])