rem: data = NULL;
add: *data = NULL;
context: getInternalSelection(WMScreen *scr, Atom selection, Atom target,		     void **data, unsigned *length){    Window owner;    SelectionHandler *handler;    /*     * Check if the selection is owned by this application and if so,     * do the conversion directly.     */    data = NULL;    owner = XGetSelectionOwner(scr->display, selection);    if (!owner)	return False;    handler = selHandlers;    while (handler) {	if (WMWidgetXID(handler->widget) == owner	    /*	    && handler->selection == event->selection*/) {	    break;	}	handler = handler->next;    }    if (!handler)	return False;    if (handler->convProc) {	Atom atom;	int format;	if (!(*handler->convProc)(handler->widget, handler->selection, 				  target, &atom, data, length, &format)) {	    return True;	}	if (handler->doneProc) {	    (*handler->doneProc)(handler->widget, handler->selection, target);	}    }    return True;}