$OpenBSD: patch-bpf_readwrite_c,v 1.2 2005/04/03 19:32:29 naddy Exp $
--- bpf_readwrite.c.orig	Wed Oct  1 21:51:36 1997
+++ bpf_readwrite.c	Sun Apr  3 21:21:24 2005
@@ -48,8 +48,10 @@ HDEV open_net_intf(int value){
 
 /*	(void) strncpy(ifr.ifr_name, device, sizeof(ifr.ifr_name)); */
   intName = getenv(ANTI_INTERFACE);
-  if (!intName)
-    (void) strncpy(ifr.ifr_name, DEVICENAME, sizeof(ifr.ifr_name)); 
+  if (!intName) {
+    intName = strdup(pcap_lookupdev(NULL));
+    (void) strncpy(ifr.ifr_name, intName, sizeof(ifr.ifr_name));
+  }
   else {
     intPtr = strrchr(intName, '/');
     if (intPtr)