gupnp是個upnp規格的實現, 它包括了resource announcement and discovery, description, control, event notification
源代码在线查看： gupnp-service-introspection.sgml
GUPnPServiceIntrospection @GUPNP_SERVICE_ACTION_ARG_DIRECTION_IN: @GUPNP_SERVICE_ACTION_ARG_DIRECTION_OUT: @name: @direction: @related_state_variable: @retval: @name: @arguments: @name: @send_events: @is_numeric: @type: @default_value: @minimum: @maximum: @step: @allowed_values: @introspection: @Returns: @introspection: @Returns: @introspection: @action_name: @Returns: @introspection: @Returns: @introspection: @Returns: @introspection: @variable_name: @Returns:
