(PECL gupnp >= 0.1.0) Get the IP address string

(PECL gupnp >= 0.1.0) Set whether or not root_device is available

(PECL gupnp >= 0.1.0) Sets up callback for variable change notification

(PECL gupnp >= 0.1.0) Get the relative location of root device.

(PECL gupnp >= 0.1.0) Set control point callback

(PECL gupnp >= 0.1.0) Get resource introspection of service

(PECL gupnp >= 0.1.0) Check whether subscription is valid to the service

(PECL gupnp >= 0.1.0) Set device callback function

(PECL gupnp >= 0.1.0) Sets a function to be called at regular intervals

(PECL gupnp >= 0.1.0) Sends out any pending notifications and stops queuing of new ones.