[xml] Beginner's question about xPath

[<ABeylin axsone com>]

Hi,

I cannot figure out how to use xPath without loading the entire XML into
memory.
Let me start of by saying that the document is stored in a proprietary
format, so I have to use our functions to read the data from the files.

I would like to use xPath without having to load entire XML into memory,
though if it's absolutely required, it will be done.
I looked at the samples on this page:
http://www.xmlsoft.org/examples/index.html#XPath, but it seems that they
load entire files into memory.  Is there a way to feed xPath memory,
much like it is possible to do this for sax parsing (using
xmlCreatePushParserCtxt)?

Thank you.
Alex