$OpenBSD$
--- applications/present3D/Cluster.cpp.orig	Wed Aug 31 00:10:45 2011
+++ applications/present3D/Cluster.cpp	Wed Aug 31 00:11:02 2011
@@ -33,7 +33,7 @@
 #if defined(__linux)
     #include <unistd.h>
     #include <linux/sockios.h>
-#elif defined(__FreeBSD__)
+#elif defined(__FreeBSD__) || defined(__OpenBSD__)
     #include <unistd.h>
     #include <sys/sockio.h>
 #elif defined(__sgi)