Whether to allow half-open connections.
A half-open connection occurs when one end of the connection has called close() or sent a FIN packet, while the other end remains open. When set to true:
- The socket won't automatically send FIN when the remote side closes its end
- The local side can continue sending data even after the remote side has closed
- The application must explicitly call
end()to fully close the connection
When false, the socket automatically closes both ends of the connection when either side closes.