update defines according to manual pageentry

git-svn-id: svn://svn.oetiker.ch/rrdtool/branches/1.2/program@1067 a5681a0c-68f1-0310-ab6d-d61299d08faa

diff --git a/configure.ac b/configure.ac
index df21955..3078710 100644 (file)
--- a/configure.ac
+++ b/configure.ac
@@ -72,7 +72,7 @@ char *strchr (), *strrchr ();
 
 /* enable posix_fadvise on linux */
 #if defined(HAVE_POSIX_FADVISE) && defined(HAVE_FCNTL_H)
-#define __USE_XOPEN2K 1
+#define _XOPEN_SOURCE 600
 #include <fcntl.h>
 #endif