$NetBSD: patch-aa,v 1.3 2009/02/09 21:11:52 joerg Exp $

--- igs/datetime.cc.orig	2009-02-09 21:39:32.000000000 +0100
+++ igs/datetime.cc
@@ -8,6 +8,7 @@
  */
 
 #define _XOPEN_SOURCE
+#define _NETBSD_SOURCE
 #ifndef _GNU_SOURCE
 #define _GNU_SOURCE 1
 #endif