[det]tcp_open_socket(+SocketId,
-StreamPair)Create streams to communicate to SocketId. If SocketId
is a master socket (see tcp_bind/2), StreamPair
should be used for
tcp_accept/3. If SocketId
is a connected (see tcp_connect/2)
or accepted socket (see tcp_accept/3), StreamPair
is unified to a stream pair (see stream_pair/3)
that can be used for reading and writing. The stream or pair must be
closed with close/1, which also closes SocketId.