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Creates a listener and waits for an accepted TCP network connection at the specified port.

Details  Examples

	net address specifies on which network address to listen. Specifying an address is useful if you have more than one network card, such as two Ethernet cards, and want to listen only on the card with the specified address. If you do not specify a network address, LabVIEW listens on all network addresses. Use the String To IP function to obtain the IP network address of the current computer.
	service name creates a known reference for the port number. If you specify a service name, LabVIEW registers the service name and the port number with the NI Service Locator.
	port is the port number on which you want to listen for a connection.
	timeout ms is the period of time in milliseconds to wait for a connection. If a connection is not established in the specified time, the VI completes and returns an error. The default value is –1, which indicates to wait indefinitely.
	error in describes error conditions that occur before this VI or function runs. The default is no error. If an error occurred before this VI or function runs, the VI or function passes the error in value to error out. This VI or function runs normally only if no error occurred before this VI or function runs. If an error occurs while this VI or function runs, it runs normally and sets its own error status in error out. Use the Simple Error Handler or General Error Handler VIs to display the description of the error code. Use error in and error out to check errors and to specify execution order by wiring error out from one node to error in of the next node. status is TRUE (X) if an error occurred before this VI or function ran or FALSE (checkmark) to indicate a warning or that no error occurred before this VI or function ran. The default is FALSE. code is the error or warning code. The default is 0. If status is TRUE, code is a nonzero error code. If status is FALSE, code is 0 or a warning code. source specifies the origin of the error or warning and is, in most cases, the name of the VI or function that produced the error or warning. The default is an empty string.
	resolve remote address indicates whether to call the IP To String function on the remote address. The default is TRUE. Refer to IP To String for more information.
	connection ID is a network connection refnum that uniquely identifies the TCP connection. Use this value to refer to this connection in subsequent VI calls.
	remote address is the address of the remote machine associated with the TCP connection. This address is in IP dot notation format.
	remote port is the port the remote system uses for the connection.
	error out contains error information. If error in indicates that an error occurred before this VI or function ran, error out contains the same error information. Otherwise, it describes the error status that this VI or function produces. Right-click the error out front panel indicator and select Explain Error from the shortcut menu for more information about the error. status is TRUE (X) if an error occurred or FALSE (checkmark) to indicate a warning or that no error occurred. code is the error or warning code. If status is TRUE, code is a nonzero error code. If status is FALSE, code is 0 or a warning code. source describes the origin of the error or warning and is, in most cases, the name of the VI or function that produced the error or warning.

TCP Listen Details

When a listen on a given port begins, you cannot use another TCP Listen VI to listen on the same port. For example, if a VI has two TCP Listen VIs on its block diagram and you start a listen on port 2222 with the first TCP Listen VI, you cannot listen on port 2222 with the second TCP Listen VI.

Examples

Refer to the following VIs for examples of using the TCP Listen VI:

• TCP Communicator - Passive VI: labview\examples\comm\TCP.llb
• Simple Data Server VI: labview\examples\comm\TCP.llb