val open_connection : sockaddr -> in_channel * out_channel
        (* Connect to a server at the given address.
           Return a pair of buffered channels connected to the server.
           Remember to call [flush] on the output channel at the right times
           to ensure correct synchronization. *)

Does not close the underlaying file descriptor when GC'd.

Is this the case with other world-state changing types?

Cheers,
Julian.