Fprintf
Fprintf(stderr, "packet data:");
Fprintf(stderr, "\n ");
Fprintf(stderr, " %02x", *p++);
Fprintf(stderr, "\n");
Fprintf(stderr, "Version %s\n", version);
Fprintf(stderr, "Usage: %s [-adDFPIlMnrvx] [-g gateway] [-i iface] \
Fprintf(stderr, "%s to %s (%s)",
Fprintf(stderr, " from %s", source);
Fprintf(stderr, ", %d hops max, %d byte packets\n", max_ttl, packlen);