Looks good, but you can't scan UDP like that. Since UDP is stateless, opening a UDP connection just sets up the local machine to send the packets out to the udp port when you write to the socket. Run it in udp mode for any port and it will tell you the port is open. I am not aware of any methods to test udp, short of actually testing udp servers that actually respond and trying to guess what service they are and how to talk to them. If anyone has ideas here or where to look, would love to hear them myself.