If your computer isn't alway on, but you want to run the periodic maintenance tasks, there's no need for a program such as MacJanitor anymore, the command line program periodic is here for you! There are a number of options that you need to specify for the program to run correctly; see the man periodic pages for more information. The basic format is:
% sudo periodic time_periodReplace time_period with one of daily, weekly, or monthly to run the associated cleanup scripts for that timeframe.
Mac OS X Hints
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