http://tronche.com/gui/x/xlib/events/processing-overview.html
http://tronche.com/gui/x/xlib/events/window-state-change/unmap.html
http://tronche.com/gui/x/xlib/events/window-state-change/reparent.html
http://www.tronche.com/gui/x/xlib/events/window-state-change/destroy.html

http://www.freedesktop.org/standards/xembed/html/lifecycle.html
http://www.freedesktop.org/standards/xembed/html/messages.html
http://www.freedesktop.org/standards/wm-spec/1.3/html/
http://www.freedesktop.org/standards/xembed/html/issues.html
http://www.freedesktop.org/standards/xembed/html/techniques.html
http://www.freedesktop.org/standards/systemtray/systemtray-spec.html