hi,

i've written a socket server. when i launch a client, it connects to servers running on various machines on my local network, which then reply to the client with some string messages, and the client exits.

however, when i launch the client repeatedly (say 5 or 6 times in quick succession) the client is unable to bind to its local port. this appears to be because servers are still trying to connect to the client machine's port, even though the client exited and shut the socket down. the actual error i receive is "Error binding socket to 192.168.1.6:44561: Address already in use".

so, is it enough just to shutdown and close a socket? is there some way that in doing so the client machine can send a CONNECTION_REFUSED message to any machine trying to connect to it? i am using PHP, not that that should make much of a difference i hope.

the problem resolves itself after around 20 seconds as the machines trying to connect to the client timeout. i still need to fix this issue though.

thanks,
haz

After you close a server socket, you should wait a while (that's TCP feature). You can also set socket option to SO_REUSEADDR. Example usage and code here:
http://php.net/manual/en/function.socket-set-option.php

ok thanks. it's not going to be used in a super high availability environment, so it shouldn't cause a problem. i'm already using SO_REUSEADDR.