TCPListen

Syntax

TCPListen (socket) Returns status

Description

Note: The flag is set according to whether Omnis was able to make a call to this external command.

This Web command is multi-threaded, allowing another thread to execute in the multi-threaded server while it runs. Note that the same socket cannot safely be used concurrently by more than one thread.

TCPListen puts a socket created with TCPSocket into listening mode. When a socket is in listening mode, it will acknowledge incoming connection requests addressed to the port bound to the socket, and place them in a queue, ready to be accepted using TCPAccept.

Socket is an Omnis Long Integer field containing the number of a socket that has been bound to a port.

Status is an Omnis Long Integer field which receives the value zero for success, or an error code < 0 for failure. Possible error codes are listed in the Web Command Error Codes Appendix.

Example

# Listen for a incoming connections on port iPort

Calculate iPort as 6000
TCPSocket Returns iSocket
TCPBind (iSocket,iPort) Returns lStatus
TCPListen (iSocket) Returns lStatus

If lStatus=0
  Repeat
    TCPAccept (iSocket) Returns lConnectedSocket
  Until lConnectedSocket>=0

  # client connected
End If

TCPClose (iSocket) Returns lStatus