--- traceroute.c.orig   Fri Aug 21 15:15:23 1998
+++ traceroute.c        Sun Aug 23 18:58:08 1998
@@ -289,6 +289,7 @@
 int nprobes = 3;
 int max_ttl = 30;
 int first_ttl = 1;
+int static_port = 0;
 u_short ident;
 u_short port = 32768 + 666;    /* start udp dest port # for probe packets */

@@ -352,7 +353,7 @@
                prog = argv[0];

        opterr = 0;
-       while ((op = getopt(argc, argv, "dFInrvxf:g:i:m:p:q:s:t:w:")) != EOF)
+       while ((op = getopt(argc, argv, "dFInrvxf:g:i:m:p:q:Ss:t:w:")) != EOF)
                switch (op) {

                case 'd':
@@ -406,6 +407,13 @@
                        options |= SO_DONTROUTE;
                        break;

+               case 'S':
+                       /*
+                        * Tell traceroute to not increment the destination
+                        * port, useful for bypassing some packet filters.
+                        * Useless without the -p option.
+                       static_port = 1;
+                       break;
                case 's':
                        /*
                         * set the ip source address of the outbound
@@ -744,7 +752,7 @@
                        register struct ip *ip;

                        (void)gettimeofday(&t1, &tz);
-                       send_probe(++seq, ttl, &t1);
+                       send_probe(static_port ? seq : ++seq, ttl, &t1);
                        while ((cc = wait_for_reply(s, from, &t1)) != 0) {
                                (void)gettimeofday(&t2, &tz);
                                i = packet_ok(packet, cc, from, seq);
@@ -1300,9 +1308,9 @@
        extern char version[];

        Fprintf(stderr, "Version %s\n", version);
-       Fprintf(stderr, "Usage: %s [-dFInrvx] [-g gateway] [-i iface] \
-[-f first_ttl] [-m max_ttl]\n\t[ -p port] [-q nqueries] [-s src_addr] [-t tos]
\
-[-w waittime]\n\thost [packetlen]\n",
+       Fprintf(stderr, "Usage: %s [-dFInrSvx] [-g gateway] [-i iface] \
+[-f first_ttl]\n\t[-m max_ttl] [ -p port] [-q nqueries] [-s src_addr] \
+[-t tos]\n\t[-w waittime] host [packetlen]\n",
            prog);
        exit(1);
 }