TCPConnectionGetOutput

function

Library: TCP/IP client and server support (OMTCP legacy, OmniMark versions 4 - 6.0.1)
Include: omtcp.xin

Returns: An external output object.

Declaration

define external string sink function TCPConnectionGetOutput
      value TCPConnection this-TCPConnection
    timeout value integer timeout-in-milliseconds optional
    protocol value IOProtocol this-IOProtocol optional
as TCPConnectionGetOutput

Purpose

This function returns an external output object, permitting writes on the connection.

If the passed TCP connection object is closed or was never connected, this function returns a dummy external output object that swallows anything written to it. At the same time, it sets the TCP connection object to be in error.

The timeout value applies primarily to data written to the returned external output. In the case of TCPConnectionGetOutput, the timeout value applies to individual write operations.

TCPConnectionGetOutput can be called once or more than once (but only if called serially) for a connection. All streams derived from a TCPConnectionGetOutput write to the same output stream attachment, but may each have their own transformation logic and buffering.

If a TCP connection from which an external output is derived is closed using TCPConnectionClose, then it is in error to perform a subsequent write to the output. The TCP connection object is set to be in error, and any data written is discarded.

The external output created by TCPConnectionGetOutput has a name. This name is the same value as that returned by TCPConnectionGetPeerName for the same TCP connection (that is, the peer name if one is available, or its IP address if not).

In general, for this function, if the time between writing two characters never exceeds the timeout value, no timeout exception occurs. If a timeout exception does occur, the operation involved discards the output text for an output or put and sets the TCPConnection to be in error. If a timeout value is not specified, it writes "block" until data is written, or until some other process indicates that an error has occurred.

Arguments:

"this-TCPConnection" is an OMX component of type TCPConnection.
"timeout-in-milliseconds" is an optional integer value that indicates the number of milliseconds the connection will wait before terminating.
"this-IOProtocol" is an optional argument specifying which I/O protocol is to be used.

Example:

  local TCPConnection TCP-Conn
  local stream s
  
  set TCP-Conn to TCPConnectionOpen on "localhost" at 5300
  TCPConnectionSetBuffering TCP-Conn enabled false
  
  open s with binary-mode as
     TCPConnectionGetOutput TCP-Conn
        protocol IOProtocolMultiPacket
  
  put s ("=" ||* 3048 || "%n") ||* 10
  put s "hello world"
  close s
  
  repeat
     exit unless TCPConnectionIsConnected TCP-Conn
     output TCPConnectionGetCharacters TCP-Conn
  again