window
, allowing you to intercept events
before they reach GDK. This is a low-level operation and makes it
easy to break GDK and/or GTK+, so you have to know what you're
doing. Pass NULL
for window
to get all events for all windows,
instead of events for a specific window.gdkWindowAddFilter(object, fun, data)
object
data
gdkDisplayAddClientMessageFilter
if you are interested
in X ClientMessage events.