[xml] how to decode a base64Binary stream?

["tcmichals" <tcmichals msn com>]

I see how to write a base64 by using xmlTextWriterWriteBase64, but how do 
you read in and decode a base64binary stream?  For example, I can find the 
node, if ((!xmlStrcmp(cur->name, (const xmlChar *)"Code"))){
ret->Code = xmlNodeListGetString(doc, cur->xmlChildrenNode, 1);

but now how to decode the xmlChar *?