--- /dev/null
+# Look up an environment variable more securely.
+dnl Copyright 2013 Free Software Foundation, Inc.
+dnl This file is free software; the Free Software Foundation
+dnl gives unlimited permission to copy and/or distribute it,
+dnl with or without modifications, as long as this notice is preserved.
+
+AC_DEFUN([gl_FUNC_SECURE_GETENV],
+[
+ dnl Persuade glibc <stdlib.h> to declare secure_getenv().
+ AC_REQUIRE([AC_USE_SYSTEM_EXTENSIONS])
+
+ AC_REQUIRE([gl_STDLIB_H_DEFAULTS])
+ AC_CHECK_FUNCS_ONCE([secure_getenv])
+ if test $ac_cv_func_secure_getenv = no; then
+ HAVE_SECURE_GETENV=0
+ fi
+])
+
+# Prerequisites of lib/secure_getenv.c.
+AC_DEFUN([gl_PREREQ_SECURE_GETENV], [
+ AC_CHECK_FUNCS([__secure_getenv])
+])