Quick OS X Tip: crontab entry to startup a GUI application on OS X

Just a quick note, about crontab and OS X.

If you want to startup a Cocoa GUI application from the commandline you can use open.

What I’ve done to startup my bittorrent client during off-peak hours is add this to my crontab:

15      2       *       *       *       /usr/bin/open /Applications/Vuze.app >& /dev/null

Which will startup Vuze at 2:15 am, the /dev/null part helps to suppress any warnings or errors.

Background

Some background on the issue, I have a ADSL2+ connection that is split between 15Gb peak and 20Gb off-peak, where the offpeak-hours are between 2 am and 12 am. So this crontab is perfect for using up all those off-peak Mbs that I would otherwise waste.

TODO

The only remaining issue is that I have no good way of killing the application when it gets to 12:00. For that I’d ideally use pkill but there isn’t a default or good implementation of that for OS X. The best remaining option is to write a ruby/python script to kill the app instead.

Update

The following entry in your crontab should kill off Vuze at 11.

*	11	*	*	*	kill `ps -A | cut -c 1-6,25-120 |grep Vuze.app |cut -c 1-6` >& /dev/null

Nasty sure, but it seems to be effective. Please test liberally on your own machine to make sure it behaves as required.