libxml2: xpath relative to sub node

Question

Given the xml file

<a>
   <b>
      <d>v</d>
   </b>
   <c>
      <d>v</d>
   </c>
</a>

And the xpath "//d/text()"

I want to apply the xpath only to c and not to the whole document.

This has to work with libxml2 2.7.6

Doing this does not work;

xmlNodePtr node = <node pointer to c>
xmlXPathContextPtr xpathCtx = xmlXPathNewContext( node->doc );
xpathCtx->node = node;

xmlXPathObjectPtr xpathObj = xmlXPathEvalExpression ( "//d/text()", xpathCtx);

Returned xpathObj contains refences to both /a/b/d and /a/c/d. Only /a/c/d was expected.

Answer 1

Use the path .//d or .//d/text() if you want to find descendants relative to another node. A path starting with //d searches all d descendant elements of the root node (also called document node).