Re: [xml] Questions on usage: xmlTextReaderCurrentDoc, XPath and xmlTextReaderRead

[Daniel Veillard <veillard redhat com>]

On Mon, Dec 24, 2007 at 04:06:27PM -0500, Eric West wrote:
[...]
> What was not obvious in the xmlTextReader+XPath example was where
> to get a pointer to the current xmlDocPtr without calling
> xmlTextReaderCurrentDoc(). I did some further experimenting and
> found that one may use the xmlDocPtr from the xmlNodePtr returned
> by xmlTextReaderExpand(). For example:
>
>    node = xmlTextReaderExpand( reader);
>    pathContext = xmlXPathNewContext( node->doc);
>    pathContext->node = node;
>    obj = xmlXPathEval( BAD_CAST xmlXPathQuery, pathContext);
>
> With this revision of my code and replacement of xmlFree() with
> the appropriate variant (eg xmlXPathFreeObject, xmlXPathFreeContext)
> I was able to get valgrind to give my code a clean bill of health.
>
> Question: is the above code sequence valid??? (Just because it works,
> is not much of a measure of correctness. :)  )

  As long as your XPath query is relative to the node and uses only
the descendants and ancestors of the node that should be reliable.

Daniel

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