Tk_GetRootCoords(tkwin, xPtr, yPtr)
Tk_Window tkwin
(in) int *xPtr
(out) int *yPtr
(out) This procedure scans through the structural information maintained by Tk to compute the root-window coordinates corresponding to the upper-left corner of tkwin's border. If tkwin has no border, then Tk_GetRootCoords returns the root-window coordinates corresponding to location (0,0) in tkwin. Tk_GetRootCoords is relatively efficient, since it doesn't have to communicate with the X server.