Taking Your Pi Off-road - Raspberry Pi for Secret Agents - page 155

Button Name Command

Set HDMI Out amixer cset numid=3 2

espeak "Something!"

eSpeak
Something

TV On echo "on 0" | cec-client -d 1 -s

TV Off echo "standby 0" | cec-client -d 1 -s

sudo reboot

Reboot Pi

Shutdown Pi sudo poweroff

Receiving status updates from the Pi
When you send your Raspberry Pi out in the world on stealthy missions, you might
not be able to stay connected to it at all times. However, as long as the Pi has Internet
access via a Wi-Fi network or USB modem, you'll be able to communicate with it
from anywhere in the world.

In this example, we'll be using Twitter, a popular social networking service for
sharing short messages. We're going to make the Pi send regular tweets about the
mission and its whereabouts. If you do not already have a Twitter account, or you'd
like a separate account for the Pi, you'll need to sign up at https://twitter.com
first. Follow these steps to get started with Twitter:

1. Before you post anything on Twitter, you should consider enabling tweet

privacy. This means the messages won't be publicly visible and only selected
people on Twitter will be able to read them.
To enable tweet privacy, go to your account settings ( https://twitter.
com/settings/account ) and check the Protect my Tweets checkbox under
Security and privacy , then click on the Save changes button.

2. Next, install a console Twitter client using the following command:

pi@raspberrypi ~ $ sudo apt-get install ttytter