$OpenBSD: patch-ifdata_c,v 1.1.1.1 2011/05/04 14:11:59 sthen Exp $
--- ifdata.c.orig	Fri Apr 29 17:12:23 2011
+++ ifdata.c	Fri Apr 29 17:19:47 2011
@@ -10,10 +10,14 @@
 	#include <linux/if.h>
 #endif
 
-#if defined(__FreeBSD_kernel__)
+#if defined(__FreeBSD_kernel__) || defined(__OpenBSD__)
 	#include <net/if.h>
 #endif
 
+#ifndef s6_addr16
+#define s6_addr16 __u6_addr.__u6_addr16
+#endif
+
 #include <netinet/in.h>
 #include <errno.h>
 #include <fcntl.h>
@@ -220,7 +224,7 @@ struct sockaddr *if_network(const char *iface) {
 	return saddr;
 }
 
-int if_mtu(const char *iface) {
+int ifd_if_mtu(const char *iface) {
 	static struct ifreq req;
 
 	if (do_socket_ioctl(iface, SIOCGIFMTU, &req, NULL, PRINT_ERROR))
@@ -388,7 +392,7 @@ void please_do(int ndo, int *todo, const char *ifname)
 				print_addr(if_bcast(ifname, &req));
 				break;
 			case DO_PMTU:
-				printf("%d", if_mtu(ifname));
+				printf("%d", ifd_if_mtu(ifname));
 				break;
 			case DO_PNETWORK:
 				print_addr(if_network(ifname));
@@ -400,7 +404,7 @@ void please_do(int ndo, int *todo, const char *ifname)
 				printf(" ");
 				print_addr(if_bcast(ifname, &req));
 				printf(" ");
-				printf("%d", if_mtu(ifname));
+				printf("%d", ifd_if_mtu(ifname));
 				break;
 #if defined(__linux__)
 			case DO_SINPACKETS: