$NetBSD: patch-ab,v 1.3 2011/11/25 22:14:17 joerg Exp $

--- interfaces-bpf.cc.orig	2003-03-17 09:32:30.000000000 +0000
+++ interfaces-bpf.cc
@@ -15,6 +15,7 @@
     GNU General Public License for more details.
 ******************************************************************************/
 
+#include <assert.h>
 #include <unistd.h>
 #include <stdio.h>
 #include <fcntl.h>
@@ -25,6 +26,8 @@
 #include <sys/time.h>
 #include <sys/socket.h>
 #include <sys/uio.h>
+#include <stdlib.h>
+#include <string.h>
 
 #include <net/if.h>
 #include <net/bpf.h>
@@ -383,7 +386,11 @@ int BPFInterfaces::send_packet(int ifn, 
   /* write this packet: */
   iov[0].iov_base = (char* )&ether_packet;
   iov[0].iov_len = sizeof(ether_packet);
+#if defined(__DragonFly__)
+  iov[1].iov_base = (char *)data;
+#else
   iov[1].iov_base = data;
+#endif
   iov[1].iov_len = len;
   if (writev(_latd_bpf_fd, iov, 2) < 0) {
     syslog(LOG_ERR, "writev: %m");