This is an extract from libxml2- 2.3.6 (ftp.xmlsoft.org), heavily
modified to work with R event loops, and with all redundant code
removed.

The original code has:

    Full documentation is available on-line at
	http://xmlsoft.org/

    This code is released under the LGPL or the W3C IPR, pick the one
    you prefer.

We choose LGPL, and distribute the modified versions under GPL.
