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May 19, 2015 - A Look At The New Commandlinefu
I've put together a short writeup on what kind of newness you can expect from the next iteration of clfu. Check it out here.
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Commands using crontab from sorted by
Terminal - Commands using crontab - 10 results
crontab -l -u USER | grep -v 'YOUR JOB COMMAND or PATTERN' | crontab -u USER -
2015-03-11 13:10:47
User: Koobiac
Functions: crontab grep

The "-u USER" is optional if root user is used

for user in $(getent passwd|cut -f1 -d:); do echo "### Crontabs for $user ####"; crontab -u $user -l; done
2012-07-11 13:06:17
User: harpo
Functions: crontab cut echo getent
Tags: crontab getent

added echo "### Crontabs for $user ####"; to make clear whose crontab is listed.

for user in $(cut -f1 -d: /etc/passwd); do echo "### Crontabs for $user ####"; crontab -u $user -l; done
2012-07-11 12:25:56
User: harpo
Functions: crontab cut echo
Tags: crontab

added echo "### Crontabs for $user ####"; to make clear whose crontab is listed.

crontab -l | sed -e '$G;$s-$-'"$CRON_MINS $CRON_HOUR"' * * * /usr/bin/command >/dev/null 2>&1-' | crontab -
2010-01-07 11:00:05
User: JohnGH
Functions: crontab sed

I needed to add a line to my crontab from within a script and didn't want to have to write my own temporary file.

You may find you need to reload the crond after this to make the change take effect.


if [ -x /sbin/service ]


/sbin/service crond reload


CRON_PID=`ps -furoot | awk '/[^a-z]cron(d)?$/{print $2}'`

if [ -n "$CRON_PID" ]





The reason I had CRON_HOUR and CRON_MINS instead of numbers is that I wanted to generate a random time between midnight & 6AM to run the job, which I did with:

CRON_HOUR=`/usr/bin/perl -e 'printf "%02d\n", int(rand(6))'` CRON_MINS=`/usr/bin/perl -e 'printf "%02d\n", int(rand(60));'`
(crontab -e) 00 12 * * * apt-get update (/etc/init.d/cron restart)
for USER in `cut -d ":" -f1 </etc/passwd`; do crontab -u ${USER} -l 1>/dev/null 2>&1; if [ ! ${?} -ne 0 ]; then echo -en "--- crontab for ${USER} ---\n$(crontab -u ${USER} -l)\n"; fi; done
2009-10-07 20:51:01
User: tharant
Functions: crontab echo

This is how I list the crontab for all the users on a given system that actually have a crontab.

You could wrap it with a function block and place it in your .profile or .bashrc for quick access.

There's prolly a simpler way to do this. Discuss.

(crontab -l; echo '* * * * * dmesg -c'; ) | crontab -
2009-09-30 18:13:38
User: syssyphus
Functions: crontab dmesg echo

this is helpful because dmesg is where i/o errors, etc are logged to... you will also be able to see when the system reboots or someone attaches a thumb drive, etc.

don't forget to set yourself up in /etc/aliases to get roots email.

vi ~/.crontab && crontab ~/.crontab
2009-08-16 08:09:15
User: micha
Functions: crontab vi

this lets you edit a crontab file (which may be used as a backup as well) and insert this into your crontab. this way is especially handy, when multiple users are working on one account (e.g. root)

crontab -e
cut -d: -f1 /etc/passwd | grep -vE "#" | xargs -i{} crontab -u {} -l
2009-06-18 16:49:52
User: hoberion
Functions: crontab cut grep xargs

additionally use "find /etc/cron*" for cronscripts