$OpenBSD: patch-src_callback_c,v 1.1 2010/10/26 16:36:59 sthen Exp $
--- src/callback.c.orig	Tue Oct 26 18:18:05 2010
+++ src/callback.c	Tue Oct 26 18:18:13 2010
@@ -24,6 +24,7 @@
 #include "user_config.h"
 #include "os.h"
 #include <stdio.h>
+#include <stdlib.h>
 #include "xstuff.h"
 #include "callback.h"
 #include "common.h"