Search for a cronjob with crontab -l

Question

I am trying to find a cronjob that was created to ensure that the script doesn't duplicate the same exact cronjob.

I've been trying to use something along these lines but haven't had much luck:

if ! crontab -l | xargs grep -l '/var/www/arix/update.php'; then
  echo "Cronjob already exists"
else
  echo "Cronjob doesn't exist"
fi

you don't need xargs. and why do you want `grep -l`? maybe just `if ! crontab -l | grep -q '....' ; then` should work. Finally, to debug the situation, execute inner element, then appending the next part, ie `crontab -l` (does that produce the output you expect?) then `crontab -l | ...` . Good luck. — shellter, Jan 22 '13 at 03:34

score 46 · Accepted Answer · answered Jan 22 '13 at 03:36

/var/spool/cron/crontabs is the usual parent directory for crontab files. There are files there that have names of users - root is the root crontab, for example. There is a potential for every user on the system to have used crontab -e and created his/her own crontab.

As root you can :

cd /var/spool/cron/crontabs
grep  'search string' *

This command (as root) will tell you what user's crontab has the string. And if it exists.

You would do this if if you are not sure what crontabs things are in. crontab -l only gives the stuff in YOUR crontab, the user who is currently logged in. If you are sure that is the best place to check:

crontab -l | grep -q 'search string'  && echo 'entry exists' || echo 'entry does not exist'

It worked! Thank you. I changed the routine to look as follows and it worked as needed. if ! crontab -l | grep -q '/var/www/arix/update1.php'; then echo "Cronjob doesn't exists" — user0000001, Jan 22 '13 at 03:41

Search for a cronjob with crontab -l

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