If you try to open a listening socket (that is - a socket that other clients can connect to), you need to provide a port number (because otherwise the clients won't know which port to connect to). If that socket is already in use, the opening will fail. You'll get an error and no-one will be able to connect with your program.

If you want to open a socket to connect to a (possibly remote) listening port, you should get assigned a random free local port number by the system and you'll be fine until you run out of ports (or open handles).

I'm not sure if you actually can open a connection to a listening port from a port number that is already in use as a listening port. I also can't think of a situation where you'd care.

"What should it profit a man, if he should win a flame war, yet lose his cool?"

In reply to Re^3: connection refused by Joost
in thread connection refused by llobrin

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