Opens a UDP socket on the port. Close the socket with the UDP Close function. Use the UDP Multicast Open VI instead of this function to open connections capable of reading, writing, or reading and writing data to or from UDP Multicast sockets. Examples

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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. | ||||||
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port is the local port with which you want to create a UDP socket. | ||||||
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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.
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connection ID is a network connection refnum that uniquely identifies the UDP socket. Use this value to refer to this socket in subsequent VI calls. | ||||||
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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 UDP 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. | ||||||
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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.
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Refer to the following VIs for examples of using the UDP Open function: