I am new to using crontab, and I've been trying to get a simple cron job. I want press F5 every 1 minute to refresh Mozzila Firefox. I am using xdotool for press F5. I have script /usr/local/bin/refresh.sh:
#!/bin/bash
xdotool search --name "Mozilla Firefox" key F5
If i run it in command line it works fine. And permission:
-rwxr-xr-x. 1 root root 89 15. čec 10.32 refresh.sh
In crontab i have:
*/1 * * * * cd /usr/local/bin && sh refresh.sh
But script run by cron doesnt work. Can anyone tell me what i do wrong?
The xdotool command is automation tool for X11 which allows you simulate keyboard/mouse input, but since crontab is run independently, it's required to define DISPLAY variable to specify which X Window System display server to use. Normally when you're login to the desktop this variable is assigned automatically, but crontab is running jobs in isolated environment (doesn't have even a tty associated), especially when you run commands via root account.
So in short, you should do define your job like:
*/1 * * * * DISPLAY=:0 /usr/local/bin/refresh.sh
Or you can define variables at the beginning of the file (in case of Vixie cron). See: Variables in crontab?
Also make sure the user which is running the job has granted access to the selected X display. If you need to grant the access, you need to assign the permission via xhost and setfacl commands and specify extra XAUTHORITY variable, see: Xdotool using “DISPLAY=:0” for more details.