The xcb-util module provides a number of libraries which sit on top of
libxcb, the core X protocol library, and some of the extension
libraries. These experimental libraries provide convenience functions
and interfaces which make the raw X protocol more usable. Some of the
libraries also provide client-side code which is not strictly part of
the X protocol but which have traditionally been provided by Xlib.

These libraries are currently included, roughly ordered by maturity:

render-util: Convenience functions for the Render extension.
aux: Convenient access to connection setup and some core requests.
atom: Standard core X atom constants and atom caching.
property: Callback X property-change handling.
icccm: Both client and window-manager helpers for ICCCM.
keysyms: Standard X key constants and conversion to/from keycodes.
event: Callback X event handling.
image: Port of Xlib's XImage and XShmImage functions.
wm: Framework for window manager implementation.

WWW: http://xcb.freedesktop.org/