xmlNs

The xmlNs structure is how namespaces are stored within the xmlTree. While the xmlNode (which represents attributes and elements) has name and contents, xmlNs has a prefix and a URI.

These structures are also much less interlinked than xmlNode's, so functions like xmlTreeGetPrevious() and xmlTreeGetParent() are not available. Only xmlTreeGetNext() can be used with xmlNs structures, which gives the next namespace declared on the element.

See the Using Namespaces section (here) below for more information on namespaces and xmlNs objects.