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explanation lives in ur hdd.

man sudo

Have a look at this thread

The answer is a ways down.

Thank you so much skymt!  That exactly what I was looking for!

I would absolutely like to learn more about the terminal and how these things work.  Is there a particular book that you would recommend for someone to start from scratch?

system.log is supposed to get rotated and compressed when the "daily" cron task is run.
it's handy to look at that log if weirdness has been occurring on your machine.

if your daily has not been run for a while, then do this in the terminal:
sudo periodic daily

likewise:
sudo periodic weekly

and:
sudo periodic monthly

< *wait for each command to complete before issuing the next command. >

you could install anacron (apple's download site) and the tasks will be run, even if your computer has been asleep or off during the scheduled times for these scripts, when your machine becomes active again.

or,
you could edit the crontab file so that the scripts are run at a time when your machine is normally on and awake.
use "cronnix" for this if you like gui tools.

there are a number of gui utilities that will let you run these three tasks (as well as other system maintenance routines...) "on demand."

Last edited by [MA] Flying_Meat (2005-03-19 1:58 pm)

trying to disable cron execution by deleting any files named crontab would be a bad idea.  rather you should edit the crontab file by commenting out lines and then refresh the crontab.  man cron and man crontab for more info.

also, I'd say it's a bad idea to run them when you feel like it.  running them too often or not often enough are equally bad or harmless.  in general, they're run at specific times for a reason   if you want to examine the output you can browse /etc/var/log/weekly.out etc.  I think that's the location anyway.  just open console.app and browse away.

greenscreen76 wrote:

well as far as how frequently you run them i've heard it doesn't really hurt to run them all several times a day if you want.

It depends on what you mean by "hurt".  The scripts (particularly weekly & monthly) make some assumptions about how frequently they run.  Also, there are a set number of retained "rolled" (compressed archived) logs before they are deleted, which will limit what can be done to research issues.  For example, the daily job keeps eight (compressed) versions of system.log, to let you look back through a week to track down issues.  If you run periodic daily eight times in a day, you no longer have the ability to look back to even the previous day.

Basically, the scripts are designed and tuned for execution on a specific frequency.  No, you probably won't break anything if you run them more often, but it isn't helpful.