参数

root_device

A root device identifier, returned by gupnp_root_device_new().

signal

The value of signal. Signal can be one of the following values:

GUPNP_SIGNAL_ACTION_INVOKED

Emitted whenever an action is invoked. Handler should process action and must call either gupnp_service_action_return() or gupnp_service_action_return_error().

GUPNP_SIGNAL_NOTIFY_FAILED

Emitted whenever notification of a client fails.

action_name

The name of action.

callback

The callback function for the certain signal. Typically, callback function takes on three parameters. The service parameter's identifier being the first, action parameter's identifier (in case GUPNP_SIGNAL_ACTION_INVOKED signal) or error parameter's message (in case GUPNP_SIGNAL_NOTIFY_FAILED signal) being the second, and the arg is third.

arg

User data for callback.