rem: result = xmlXPathEvalExpression(xpath, context);
add: result = xmlXPathEvalExpression((xmlChar*)xpath, context);
context: xmlNodePtr xpath_get_node(xmlDocPtr doc, char *xpath){	xmlXPathContextPtr context;	xmlXPathObjectPtr result;	xmlNodeSetPtr nodeset;	xmlNodePtr node;	context = xmlXPathNewContext(doc);	result = xmlXPathEvalExpression(xpath, context);	if(xmlXPathNodeSetIsEmpty(result->nodesetval)){		fprintf(stderr, "xpath_get_node: no result for xpath=%s\n", xpath);		return NULL;	}	nodeset = result->nodesetval;	node = nodeset->nodeTab[0];	xmlXPathFreeContext(context);	return node;}