+ if(opt_mark != NULL)
+ {
+ char *endp;
+ int mark = strtoul(opt_mark, &endp, 0);
+ if(opt_mark[0] != '\0' && *endp == '\0')
+ {
+ if(ping_setopt(ping, PING_OPT_MARK, (void*)(&mark)) != 0)
+ {
+ fprintf (stderr, "Setting mark failed: %s\n",
+ ping_get_error (ping));
+ }
+ }
+ else{
+ fprintf(stderr, "Ignoring invalid mark: %s\n", optarg);
+ }
+ }
+