C: LOGOUT
      S: * BYE Goodbye
The SMAP client disconnects from the server by sending the
    LOGOUT command. The server
    terminates the connection after sending the * BYE reply. The server should also try to
    send the * BYE command at any time
    the connection to the client needs to be terminated due to some
    unexpected reason. The client always be prepared to handle
    * BYE.