MacOS – Cron script not executing on Mavericks

cronmacos

I have configured a user crontab file as follows:

*/2 * * * * /Users/[my user]/Dropbox/htdocs/auto-update.sh

But it won't execute. I waited for, like, 10-15 minutes. Why?

Command auto-update.sh runs easily if executed manually. How can I break apart the chain of execution and get my script running from cron?

Best Answer

The environment a cron job runs in is quite a bit different from an interactive shell; it's likely that the script is running, but not successfully. One of the biggest differences are that for cron jobs, the default PATH is just "/usr/bin:/bin", so if you use any commands that aren't in /usr/bin or /bin, they won't be found unless your script either sets its own PATH, or supplies explicit paths to commands. The other big difference is simply that it's not connected to an interactive session, so if it tries to do anything interactive (read from the terminal, etc) that'll fail. Try changing the cron entry to:

*/2 * * * * /Users/[my user]/Dropbox/htdocs/auto-update.sh >>/tmp/auto-update.log 2>&1

...and see if anything informative shows up in the log.

Related Solutions

MacOS – Cron configuration on Mavericks

This should be working and is certainly working on my Mavericks box.

If you don't have a "MAILTO" line in the crontab then output should get sent to the owner of the crontab.

Are you sure the job actually outputs something? Have you tried putting a job in the crontab that will be sure to have some output such as

*/10 * * * * *  /bin/echo "Working fine"

Are you sure you don't have a .forward file in the user home directory?

Have you tried using sendmail to send some mail to the account and see if it gets through.

MacOS – launchctl error “nothing found to load” when run via cron

The problem is execution context and mach bootstrap in OS X (more info on Apple documentation worth reading). You need to simulate execution from proper context. In OS X it's done using launchctl bsexec command. From TheDarkKnight's answer to Starting/stopping a launchd agent for all users with GUI sessions you have:

Unload Agents

#!/bin/bash
for id in `ps aux | grep -v grep | grep MyAgent | awk {'print $2'}`
do
    launchctl bsexec $id launchctl unload /Library/LaunchAgents/myAgent.plist
done

Replace MyAgent with the name of your Launch Agent.

Load Agents

#!/bin/bash
for pid_uid in $(ps -axo pid,uid,args | grep -i "[l]oginwindow.app" | awk '{print $1 "," $2}'); do

    pid=$(echo $pid_uid | cut -d, -f1)
    uid=$(echo $pid_uid | cut -d, -f2)

    launchctl bsexec "$pid" chroot -u "$uid" / launchctl load /Library/LaunchAgents/myAgent.plist
done

On OS X 10.11 and Later

From the comment by vrrathod about OS X 10.11, El Capitain, use:

launchctl bootstrap gui/$uid /Library/LaunchAgents/myAgent.plist