--- /dev/null
+# getcwd.m4 - check whether getcwd (NULL, 0) allocates memory for result
+
+# Copyright 2001 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 2, 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, write to the Free Software Foundation,
+# Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA. */
+
+# Written by Paul Eggert.
+
+AC_DEFUN([AC_FUNC_GETCWD_NULL],
+ [AC_CHECK_HEADERS(stdlib.h unistd.h)
+ AC_CACHE_CHECK([[whether getcwd (NULL, 0) allocates memory for result]],
+ [ac_cv_func_getcwd_null],
+ [AC_TRY_RUN(
+ [
+# ifdef HAVE_STDLIB_H
+# include <stdlib.h>
+# endif
+# ifdef HAVE_UNISTD_H
+# include <unistd.h>
+# endif
+# ifndef getcwd
+ char *getcwd ();
+# endif
+ int
+ main ()
+ {
+ if (chdir ("/") != 0)
+ exit (1);
+ else
+ {
+ char *f = getcwd (NULL, 0);
+ exit (! (f && f[0] == '/' && !f[1]));
+ }
+ }],
+ [ac_cv_func_getcwd_null=yes],
+ [ac_cv_func_getcwd_null=no],
+ [ac_cv_func_getcwd_null=no])])
+ if test $ac_cv_func_getcwd_null = yes; then
+ AC_DEFINE(HAVE_GETCWD_NULL, 1,
+ [[Define if getcwd (NULL, 0) allocates memory for result.]])
+ fi])