$NetBSD$

--- Interface.xs.orig	2008-06-06 17:51:42.000000000 +0200
+++ Interface.xs
@@ -511,6 +511,9 @@ if_netmask(sock, name, ...)
 	  operation = SIOCGIFNETMASK;
      }
      if (!Ioctl(sock,operation,&ifr)) XSRETURN_UNDEF;
+#ifdef __NetBSD__
+     ifr.ifr_addr.sa_family = AF_INET;
+#endif
      if (ifr.ifr_addr.sa_family != AF_INET) croak ("Address is not in the AF_INET family.\n");
      RETVAL = inet_ntoa(((struct sockaddr_in*) &ifr.ifr_addr)->sin_addr);
 #endif
