gdk: Document gdk_window_add_filter()+XGenericEvents behavior

diff --git a/gdk/gdkwindow.c b/gdk/gdkwindow.c
index 840fdbf1fa85f22692f129a75f22af01ae886982..0be4656b85e8dfbcf6a5a939968fb3615d661652 100644 (file)
--- a/gdk/gdkwindow.c
+++ b/gdk/gdkwindow.c
@@ -2410,6 +2410,10 @@ gdk_window_peek_children (GdkWindow *window)
  *
  * See gdk_display_add_client_message_filter() if you are interested
  * in X ClientMessage events.
+ *
+ * If you are interested in X GenericEvents, bear in mind that
+ * XGetEventData() has been already called on the event, and
+ * XFreeEventData() must not be called within @function.
  **/
 void
 gdk_window_add_filter (GdkWindow     *window,