+
+rtmsg(cmd)
+{
+ static int seq;
+ int rlen;
+ register struct rt_msghdr *rtm = &m_rtmsg.m_rtm;
+ register char *cp = m_rtmsg.m_space;
+ register int l;
+
+ errno = 0;
+ if (cmd == RTM_DELETE)
+ goto doit;
+ bzero((char *)&m_rtmsg, sizeof(m_rtmsg));
+ rtm->rtm_flags = flags;
+ rtm->rtm_version = RTM_VERSION;
+
+ switch (cmd) {
+ default:
+ fprintf(stderr, "arp: internal wrong cmd\n");
+ exit(1);
+ case RTM_ADD:
+ rtm->rtm_addrs |= RTA_GATEWAY;
+ rtm->rtm_rmx.rmx_expire = expire_time;
+ rtm->rtm_inits = RTV_EXPIRE;
+ rtm->rtm_flags |= RTF_HOST;
+ sin_m.sin_other = 0;
+ if (doing_proxy) {
+ if (export_only)
+ sin_m.sin_other = SIN_PROXY;
+ else {
+ rtm->rtm_addrs |= RTA_NETMASK;
+ rtm->rtm_flags &= ~RTF_HOST;
+ }
+ }
+ case RTM_GET:
+ rtm->rtm_addrs |= RTA_DST;
+ }
+#define NEXTADDR(w, s) \
+ if (rtm->rtm_addrs & (w)) { \
+ bcopy((char *)&s, cp, sizeof(s)); cp += sizeof(s);}
+
+ NEXTADDR(RTA_DST, sin_m);
+ NEXTADDR(RTA_GATEWAY, sdl_m);
+ NEXTADDR(RTA_NETMASK, so_mask);
+
+ rtm->rtm_msglen = cp - (char *)&m_rtmsg;
+doit:
+ l = rtm->rtm_msglen;
+ rtm->rtm_seq = ++seq;
+ rtm->rtm_type = cmd;
+ if ((rlen = write(s, (char *)&m_rtmsg, l)) < 0) {
+ if (errno != ESRCH || cmd != RTM_DELETE) {
+ perror("writing to routing socket");
+ return (-1);
+ }
+ }
+ do {
+ l = read(s, (char *)&m_rtmsg, sizeof(m_rtmsg));
+ } while (l > 0 && (rtm->rtm_seq != seq || rtm->rtm_pid != pid));
+ if (l < 0)
+ (void) fprintf(stderr, "arp: read from routing socket: %s\n",
+ strerror(errno));
+ return (0);
+}
+
+quit(msg)
+char *msg;
+{
+ fprintf(stderr, "%s\n", msg);
+ exit(1);
+}