Cron/Crontab

loocw · 03-07-2001, 12:32 AM

Hi,

What is the different between cron and crontab?
How to use cron?
Can someone give me an examples?
wat is the meaning of below example?
*/10 * * * * root /sbin/rmmod -as
I have a perl script that need to be run periodically,
how do i use cron or crontab to do that?
Pls Advice
Thanks

Regards
Kelvin Loo

jeremy · 03-07-2001, 10:07 PM

cron is the daemon that executes scheduled commands. crontab maintains the crontab files for individual users. The example you gave would run the command "/sbin/rmmod -as
" every ten minutes.

The first five fields are:

Code:

 field          allowed values
 -----          --------------
 minute         0-59
 hour           0-23
 day of month   1-31
 month          1-12 (or names, see below)
 day of week    0-7 (0 or 7 is Sun, or use names)

loocw · 03-08-2001, 02:16 AM

Hi Jeremy,

Thanks for ur reply!!
So if I want to run my file "update.pl" weekly,
How should I write?
Becos, it is a perl script so I will need to run perl program ...... so in the filename side, should I write something like this -> perl update.pl
and the timimg will be -> *****/Mon
so the overall will look like that -> *****/Mon perl /home/kelvin/update.pl
is that correct?

And btw, where should I put this line of code becos my system don't have crontab, instead, it have cron.d, cron.daily, cron.weekly, etc......
Should I activate the CRON command to start running the above code?
Pls advise
Thanks

Regard
Kelvin Loo