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Creates a listener for a TCP network connection. Wire 0 to the port input to dynamically choose an available TCP port the operating system determines is valid for use. Use the TCP Open Connection to query the NI Service Locator for the port number registered with the service name.

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 specifies the time in milliseconds to wait before the function completes and returns an error. The default value is 25,000 ms or 25 seconds. A value of -1 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.
	listener ID is a network connection refnum that uniquely identifies the listener.
	port returns the port number the function used. If the input port is not zero, the output port number equals the input port number. Wire 0 to the port input to dynamically choose an available TCP port the operating system determines is valid for use. As defined by the Internet Assigned Numbers Authority (IANA), valid port numbers are between the range of 49152 through 65535. Well Known Ports are between the range of 0 through 1023 and Registered Ports are between the range of 1024 through 49151. Not all operating systems follow the IANA standard; for example, Windows returns dynamic ports between the range of 1024 through 5000.
	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.

Examples

Refer to the following VIs for examples of using the TCP Create Listener function:

• Named Service TCP Server VI: labview\examples\comm\TCP.llb
• Named Service TCP Client VI: labview\examples\comm\TCP.llb