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Subscribes to the specified shared variables and begins generating notifications. Call this VI multiple times to add to the list of shared variables being monitored for value changes.

	notification refnum is a user event refnum created by the Enable Value Change Notifications VI.
	shared variables is the list of shared variables for which you want value change notifications.
	updates to buffer (no buffer) specifies how many value changes LabVIEW buffers for the specified shared variables. If you do not provide a buffer, LabVIEW generates notifications only for the most recent value of the shared variable. Some intermediate values of shared variables that change rapidly might not generate notifications. Only request a buffer if the VI needs to monitor every value change of a shared variable because buffering can reduce performance. This buffer only controls the behavior of the client application. You must configure buffering on the server with the shared variable.
	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.
	shared variable value change notification returns the strictly typed user event refnum.
	shared variables out returns a copy of the shared variables input.
	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.