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shutdown SOCKET,HOW

Shuts down a socket connection in the manner indicated by HOW, which has the same interpretation as in the syscall 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.

Returns 1 for success; on error, returns undef if the first argument is not a valid filehandle, or returns 0 and sets $! for any other failure.