strtoport
int strtoport(char *portstr, int udp);
hi = strtoport(n, uflag);
lo = strtoport(p, uflag);
hi = strtoport(p, uflag);
port = strtoport(str, &end, 0, 0);
i = strtoport(st, &end, 0 /* base */, 0 /* proto */);
a = strtoport(av, &str, 0, proto);
b = strtoport(av, &str, 0, proto);