cron job hdmi on and off

Sam 0

Re: [Cron Job Question](/tI used a cron job to turn my screen off and on I still want to do this I understand that the addressing of the monitor has changed and now only the code below works:

Turn off display Sunday - Thursday at 22:00

00 22 * * 0-4 wlr-randr --output HDMI-A-1 --off

Turn off display Friday - Saturday at 22:45

45 22 * * 5,6 wlr-randr --output HDMI-A-1 --off

Turn on screen Monday - Friday at 7:00

00 07 * * 1-5 wlr-randr --output HDMI-A-1 --on

Turn on screen Saturday - Sunday at 8:00

00 08 * * 6,0 wlr-randr --output HDMI-A-1 --onopic/16967/cron-job-question)

i see that running the commands:
wlr-randr --output HDMI-A-1 --off
wlr-randr --output HDMI-A-1 --on
works fine
only putting this in cron and making it work didn’t work. i think i need to point the above cron job to files to have it run by cronjob can someone give a good example of what this looks like

Sam 0

ok is this good now? :) let me know the result tomorrow…

mumblebaj

@Sam-0 Have a look at my post about this.

https://forum.magicmirror.builders/topic/19116/having-trouble-with-screen-on-and-off-here-are-some-tips-that-could-help?_=1743776945326

Sam 0

@Sam-0 thanks I will test it and share the result with you

Sam 0

i created two files
off.sh and on.sh
they contain the following lines

wlr-randr --output HDMI-A-1 --off
wlr-randr --output HDMI-A-1 --on

i also created a folder
with the following rights:
cmod 777
the cron contains the following lines:
unfortunately this does not work what is wrong?

# Schakel display uit zondag - donderdag om 22.00
00 22 * * 0-4 /home/username/MagicMirror/config/hdmionoff/off.sh>> /home/username/MagicMirror/config/hdmionoff/mof.log 2>&1
# Schakel display uit vrijdag - zaterdag om 22.45
45 22 * * 5,6 /home/username/MagicMirror/config/hdmionoff/off.sh>> /home/username/MagicMirror/config/hdmionoff/mof.log 2>&1
# Zet het scherm aan maandag - vrijdag om 7u00
00 07 * * 1-5/home/username/MagicMirror/config/hdmionoff/on.sh>> /home/username/MagicMirror/config/hdmionoff/mon.log 2>&1
# Zet het scherm aan zaterdag - zondag om 8u00
00 08 * * 6,0/home/username/MagicMirror/config/hdmionoff/on.sh>> /home/username/MagicMirror/config/hdmionoff/mon.log 2>&1

sdetweil

@Sam-0 are the sh files marked executable?

ls -laF in your folder to see

permissions are 3 groups of 3 settings
read/write/execute
for user, group and all others
9 settings from the right
one more for directory and 1 for system

ds, user, group, other

Sam 0

I thought it was right but now the rights on the sh files are set to 0777 and also on the folders
I also did a test to see if I could execute the sh files, this works tonight the cron should execute it, let me know if it works

sdetweil

@Sam-0 yes. although you dont need write permission, (except for user)
means anyone else could change the script

evroom

@Sam-0 said in cron job hdmi on and off:

i created two files
off.sh and on.sh
they contain the following lines

wlr-randr --output HDMI-A-1 --off
wlr-randr --output HDMI-A-1 --on

Do you have #!/bin/bash or #!/bin/sh at the very beginning of your shell scripts ?

#! /bin/sh – Execute the file using the Bourne shell, or a compatible shell, assumed to be in the /bin directory
#! /bin/bash – Execute the file using the Bash shell

You can also put /bin/bash in the crontab entry (before /home/username/...).
Then there is no way for cron to not execute it as a shell script and it will even run without the executable bit set.

And what Sam mentioned: the scripts need to be executable but not necessarily writable (chmod 755).
This should normally do the trick.

If you have mail installed (which mail) you can put this at the very beginning of the crontab file:
MAILTO=username (in my case admin).
With
journalctl --since "1 day ago" --unit cron.service --no-pager
you can see if cron ran your script and with mail you can see more details on the cron job executed.

Good luck.

Sam 0

@evroom Thanks for your explanation, I have made adjustments and will check tonight if it works. I will report this back. Thanks for the effort.

Sam 0

unfortunately it still doesn’t work what am I doing

wrong?!

cron info

on sh file

off sh file

error logfile: