ndp_usage
ndp_usage("Missing link-layer address after "
ndp_usage("Encountered \"%s\" after "
ndp_usage("Unrecognized flag \"-%c\"", optopt);
ndp_usage(NULL);
ndp_usage("Extra arguments leftover after parsing flags");
ndp_usage("Multiple arguments given without any flags");
ndp_usage("Given period should be a positive integer,"
ndp_usage("Given period should be shorter than a day;"
ndp_usage("Already going to print an entry, "
ndp_usage("Already going to print all entries (-a), "
ndp_usage("Already going to repeatedly print all entries (-A), "
ndp_usage("Already going to delete an entry (-d), "
ndp_usage("Already going to set an entry (-s), "
ndp_usage("Already going to set from file (-f), "
ndp_usage("Missing time period after -%c", flag);
ndp_usage("Missing node name after -%c", flag);
ndp_usage("Missing filename after -%c", flag);
ndp_usage("Missing node name after -%c", flag);
ndp_usage("Missing interface name after -%c", flag);
ndp_usage("Missing option argument after -%c", flag);
static void ndp_usage(const char *, ...);
ndp_usage("No arguments given.");