Home Hacking Projects for Geeks

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Part I: Home Automation

(when the script creates a new fold-

er). So, to make sure everything is

working correctly, grab one of your

motion detectors and press the

“House/On” button. You should see

output that resembles the screenshot

shown in Figure 3-7.

You’ll probably see the script take

a picture immediately because you

triggered the motion detector since

connecting the X10 computer inter-

face. The X10 computer interface

keeps the last few messages in a

queue.

If things don’t work as expected, try moving your X10 computer interface and the

wireless transceiver to different electrical outlets. You might even try connecting

them to outlets right next to each other.

10. Schedule the script

Your script relies on your computer running. You don’t want to have to

remember to restart the script each time the computer restarts, so you

should configure your script to run automatically at startup. To do this,

execute the following commands:

su

echo perl /home/

username/homehacking/pet-monitor.pl >> /etc/rc.d/

rc.local

This adds the Perl command to run your new script to the rc.local file,

which Linux automatically executes at startup. Restart your system, and

the script will automatically run and snap pictures when your pet moves.

You’re done!

If you discover that the script doesn’t work when started automatically, ...