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Reads a datagram from a UDP socket, returning the results in data out.

The function returns data when it receives any bytes, and waits the full timeout ms only if it receives no bytes.

Examples

	connection ID is a network connection refnum that uniquely identifies the UDP socket.
	max size is the maximum number of bytes to read. The default is 548. (Windows) If you wire a value other than 548 to this input, Windows might return an error because the function cannot read fewer bytes than are in a packet.
	timeout ms is in milliseconds. If no bytes have been received within the specified time, the function completes and returns an error. The default is 25,000 ms. 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.
	connection ID out returns the same value as connection ID.
	data out contains the data read from the UDP datagram.
	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.
	port is the port of the UDP socket that sent the datagram.
	address is the address of the computer where a datagram originates.

Examples

Refer to the following VIs for examples of using the UDP Read function:

• UDP Multicast Receiver VI: labview\examples\comm\UDP.llb
• UDP Receiver VI: labview\examples\comm\UDP.llb
• UDP Multicast Send Recv VI: labview\examples\comm\UDP.llb