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pythonsocketssocketserver

Close server socket on quit/crash

I'm learning how to use sockets in python, and quite often when my program crashes or I Ctrl+C the server socket somehow stays listening on the port. This obviously stops the program from listening on that port when it starts back up again, so I have to keep changing it.

I'm guessing I need to do socket.close() somewhere, but where?

Solution

  • You could try the atexit module.

    import atexit

function close_socket:
    s.close()

atexit.register(close_socket)

    If the issue is delays in the port becoming available during testing, I would suggest setting SO_REUSEADDR which will allow the port to be bound again immediately instead of waiting for timeouts on the TCP stack. 

    s.setsockopt(socket.SOL_SOCKET, socket.SO_REUSEADDR, 1)