-- Perl 5.8.7 documentation --
  • shutdown SOCKET,HOW

    Shuts down a socket connection in the manner indicated by HOW, which has the same interpretation as in the system call of the same name.

        shutdown(SOCKET, 0);    # I/we have stopped reading data
        shutdown(SOCKET, 1);    # I/we have stopped writing data
        shutdown(SOCKET, 2);    # I/we have stopped using this socket

    This is useful with sockets when you want to tell the other side you're done writing but not done reading, or vice versa. It's also a more insistent form of close because it also disables the file descriptor in any forked copies in other processes.