novski:
i found a bridge.get(key, buffer, buffer_length) in the bridge reference but can not find out what the key should be nor a list of key words...
YOU define the list of key words, there are non that are pre-defined. Basically, any string you use as a key for a Bridge.put() can be used later in a Bridge.get() call. It is a way of storing and retrieving data as a series of key/value pairs in a manner that can be read or written by the sketch, by code running on the Linux side, or remotely by using http://arduino.local/data/put/key/value or http://arduino.local/data/get/key.
The ifconfig command mentioned by sonnyyu will give the IP of both the WiFi and wired network connections.