Turning your TV on or off using the Pi

For this example, we are relying on a technology called Consumer Electronics Control (CEC), which is a feature of the HDMI standard for sending control messages to your home electronics equipment.

To help us send these messages, we'll need a software package called libCEC. Unfortunately, the libCEC version that is currently part of the Raspbian package repository doesn't actually support the Raspberry Pi, so we'll need to build our own software from source code.

1. Before building the software, we will need to add some developer headers and code libraries that libCEC relies on:

   pi@raspberrypi ~ $ sudo apt-get install autoconf libtool libudev-dev liblockdev1-dev
   

2. Next, we check out the libCEC source code from the project's Git repository:

   pi@raspberrypi ~ $ git clone git://github.com/Pulse-Eight/libcec.git
   

3. Now we enter the source directory and build the software using the following sequence of commands:

   pi@raspberrypi ~ $ cd libcec
   pi@raspberrypi ~/libcec...