Returns the chain of callers from the current VI to the top-level VI.
Element 0 of the call chain array contains the name of the lowest VI in the call chain. Subsequent elements are callers of the lower VIs in the call chain. The last element of the call chain array is the name of the top-level VI.
If you are using the current VI as a subVI, use this node to identify all the VIs that call the subVI.