--- sim_fio.c.orig	Sun Nov 20 03:55:26 2011
+++ sim_fio.c	Sun Nov 20 03:56:43 2011
@@ -302,7 +302,7 @@ return fseeko64 (st, xpos, origin);
 
 /* Apple OS/X */
 
-#if defined (__APPLE__) || defined (__FreeBSD__)
+#if defined (__APPLE__) || defined (__FreeBSD__) || defined (__OpenBSD__)
 #define _SIM_IO_FSEEK_EXT_      1
 
 int sim_fseek (FILE *st, t_addr xpos, int origin)