"One of the most complex aspects of Xlib programming is designing
the event loop, which must take into account all of the possible events that
can occur in a window."
-- Nye & O'Reilly X Toolkit Intrinsics Programming Manual, vol. 4, 1990, p. 241.
"The dispatching and handling of events is rather
-- Galaxy Reference Manual, v1.2, p. 20-5.