Bail if we don't get a listening socket.

git-svn-id: http://www.varnish-cache.org/svn/trunk/varnish-cache@795 d4fa192b-c00b-0410-8231-f00ffab90ce4

bin/varnishd/varnishd.c

@@ -397,7 +397,8 @@ main(int argc, char *argv[])
 	 * but do not answer.  That, on the other hand, would eliminate the
 	 * possibility of doing a "no-glitch" restart of the child process.
 	 */
-	open_tcp(portnumber);
+	if (open_tcp(portnumber))
+		exit (2);
 
 	VSL_MgtInit(SHMLOG_FILENAME, 8*1024*1024);