(rpl_calloc): Defend against buggy calloc implementations

[gnulib.git] / m4 / putenv.m4

diff --git a/m4/putenv.m4 b/m4/putenv.m4
index c95418b..0bb17f4 100644 (file)
--- a/m4/putenv.m4
+++ b/m4/putenv.m4
@@ -1,12 +1,17 @@
-#serial 2
+# putenv.m4 serial 8
+dnl Copyright (C) 2002, 2003, 2004 Free Software Foundation, Inc.
+dnl This file is free software, distributed under the terms of the GNU
+dnl General Public License.  As a special exception to the GNU General
+dnl Public License, this file may be distributed as part of a program
+dnl that contains a configuration script generated by Autoconf, under
+dnl the same distribution terms as the rest of that program.
 
 dnl From Jim Meyering.
 dnl
 dnl Check whether putenv ("FOO") removes FOO from the environment.
 dnl The putenv in libc on at least SunOS 4.1.4 does *not* do that.
-dnl
 
-AC_DEFUN(jm_FUNC_PUTENV,
+AC_DEFUN([gl_FUNC_PUTENV],
 [AC_CACHE_CHECK([for SVID conformant putenv], jm_cv_func_svid_putenv,
   [AC_TRY_RUN([
     int
@@ -33,9 +38,14 @@ AC_DEFUN(jm_FUNC_PUTENV,
             jm_cv_func_svid_putenv=no)
   ])
   if test $jm_cv_func_svid_putenv = no; then
-    AC_SUBST(LIBOBJS)
-    LIBOBJS="$LIBOBJS putenv.$ac_objext"
-    AC_DEFINE_UNQUOTED(putenv, rpl_putenv,
-      [Define to rpl_memcmp if the replacement function should be used.])
+    AC_LIBOBJ(putenv)
+    AC_DEFINE(putenv, rpl_putenv,
+      [Define to rpl_putenv if the replacement function should be used.])
+    gl_PREREQ_PUTENV
   fi
 ])
+
+# Prerequisites of lib/putenv.c.
+AC_DEFUN([gl_PREREQ_PUTENV], [
+  AC_CHECK_HEADERS_ONCE(unistd.h)
+])