    /*
     *  call-seq:
     *    attribute_nodes()
     *
     *  returns a list containing the Node attributes.
     */
    static VALUE attribute_nodes(VALUE self)
    {
        /* this code in the mode of xmlHasProp() */
        xmlNodePtr node ;
        VALUE attr ;

        attr = rb_ary_new() ;
        Data_Get_Struct(self, xmlNode, node);

        Nokogiri_xml_node_properties(node, attr);

        return attr ;
    }