mdw@git.distorted.org.uk Git - runlisp/blob - .ext/cfd/m4/mdw-decl-environ.m4

   1 dnl -*-autoconf-*-
   2
   3 ### SYNOPSIS
   4 ###
   5 ###   mdw_DECL_ENVIRON
   6 ###
   7 ### DESCRIPTION
   8 ###
   9 ###   Define a preprocessor symbol `DECL_ENVIRON' if the `environ' vector is
  10 ###   declared in one of the `usual' places.
  11 ###
  12 ### LICENSE
  13 ###
  14 ###   Copyright (c) 1999 Mark Wooding <mdw@distorted.org.uk>
  15 ###
  16 ###   This program is free software: you can redistribute it and/or modify it
  17 ###   under the terms of the GNU General Public License as published by the
  18 ###   Free Software Foundation, either version 2 of the License, or (at your
  19 ###   option) any later version.
  20 ###
  21 ###   This program is distributed in the hope that it will be useful, but
  22 ###   WITHOUT ANY WARRANTY; without even the implied warranty of
  23 ###   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
  24 ###   General Public License for more details.
  25 ###
  26 ###   You should have received a copy of the GNU General Public License along
  27 ###   with this program. If not, see <http://www.gnu.org/licenses/>.
  28 ###
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  41
  42 # serial 1
  43 AC_DEFUN([mdw_DECL_ENVIRON],
  44 [AC_CACHE_CHECK([for declaration of \`environ'], mdw_cv_environ,
  45 [AC_EGREP_CPP([\<environ\>],
  46 [#include <sys/types.h>
  47 #if HAVE_UNISTD_H
  48 #include <unistd.h>
  49 #endif
  50 #if STDC_HEADERS
  51 #include <stdlib.h>
  52 #include <stddef.h>
  53 #endif], [mdw_cv_environ=yes], [mdw_cv_environ=no])])
  54 if test $mdw_cv_environ = yes; then
  55   AC_DEFINE([DECL_ENVIRON], [1],
  56             [Define if you have the `environ' vector of environment variables.])
  57 fi])