You can pass either a timestamp or CurrentTime . Otherwise, the last-change time is set to the specified time, with CurrentTime replaced by the current server time. Otherwise, the owner of the selection becomes the client executing the request. The selection atom is uninterpreted by the X server. XGetSelectionOwner returns the owner window, which is reported in SelectionRequest and SelectionClear events.
Selections are global to the X server.
XSetSelectionOwner can generate BadAtom and BadWindow errors. The XGetSelectionOwner function returns the window ID associated with the window that currently owns the specified selection. If no selection was specified, the function returns the constant None . If None is returned, there is no owner for the selection. XGetSelectionOwner can generate a BadAtom error.