[SOLVED] Kodi on RPi4 on LibreELEC - run custom script upon "Kodi power-off"

Hello forum,

I would like to run a custom BASH script as the user chooses to power-down Kodi via the GUI.

The script uses variable assignment, the date fuction, netcat and a while/do loop.

I know cron cannot be used for running scripts at/before shutdown.

I'm running Kodi 19.3 Matrix on a 4GB RPi with LibreELEC 10.0.1.

Thanks for your time.

Best regards,

Rembrandt

PS: EDIT 1 this does not work - tested

Would I be able to start a BASH script via cron @reboot that checks ps aux | grep kodi

for the likes of :

1067 root 0:00 {kodi.sh} /bin/sh /usr/lib/kodi/kodi.sh --standalone -fs

1081 root 7:59 /usr/lib/kodi/kodi.bin --standalone -fs

and if these, or one of them disappear, assume that Kodi is going down?

Thanks.

Thanks JoeAverage,

The code that runs in cron @reboot is:

while [ $( ps aux | grep -v grep | grep -c kodi ) -eq 2 ] ; do sleep 1; done; /storage/bin/RunScriptAtKodiPowerDown.sh

I could use pgrep instead, had forgotten about it.

However, I think that the order of shutting down services/deamons/processess etc prevents this from ever exiting the while-loop, i.e. the above BASH code gets 'unloaded', removed from memory before the while condition ever reaches "not-equal". This is a hunch.

Perhaps there is another way to do this?

BR

Rembrandt

PS: EDIT 1

I suspect running / starting my script at power-down needs to be organised differently, so that the RPi does not keep shutting down parts of the OS etc as my BASH script is still running, i.e. my script would need to be run between the signal to power down and the start of the actual power-down procedure.

Thanks mglae, having a look at your information.

Rembrandt

Gentlemen, gentlewomen

Here's an interesting link I was made aware of, last modified a year ago:

https://wiki.libreelec.tv/configuration/startup-shutdown

Toodles

OK forum, thank you so far.

To recap, I'm trying to run a custom script as Kodi "Power Off System" is clicked on a RPi-4 under LibreELEC.

I now have the following code.

/storage/.config/shutdown.sh which has execute rights :

-rwxr-xr-x    1 root     root           474 Jan 16 10:40 /storage/.config/shutdown.sh

shutdown.sh :

#! /bin/bash

case "$1" in
  halt)
    # your commands here
    ;;
  poweroff)

        IP="111.222.333.444"
        port=7294
        msg="Message-01"
        timeout=10

        let endtime=$(date +%s)+$timeout
        echo "$msg" | nc -w 1 "$IP" $port
        ec=$?

        while [[ $(date -u +%s) -le $endtime ]] && [[ $ec -ne 0 ]] ; do
                echo "$msg" | nc -w 1 "$IP" $port
                ec=$?
        done
    ;;
  reboot)
    # your commands here
    ;;
  *)
    # your commands here
    ;;
esac

The "power-off" case does not seem to get triggered and I do not want it in all-other cases.

When I run the above ( power-off case) code in a script, saved as a sh file, directly from the command line, it works each and every time.

That was from Raspbian - I have to correct some things - I apologise.

Code corrected.

Do I perhaps need to enable the use of the shutdown.sh ?

Perhaps I have to add the full paths to each command in the shutdown.sh script ?

BR

Rembandt

Yup, duh. Thanks frakkin64,

Upon Kodi power-off-system, I want to send a message to a headless RPi4 to shutdown properly via "shutdown -P now" or similar.

Would there be another way that avoids having to use the GPIO to communicate between the two RPis?

Thanks

I'm looking at this thread that might help, but it is a little over my head.

Could anyone give some hints?

How to write a Systemd unit that will fire before networking goes down

I want to run a script when a user shuts their computer down, but it needs networking. So I'd like it to run when the system is heading for shutdown (or…

unix.stackexchange.com

Thank you.

Thank you frakkin64 and mglae.

Something f00d for thought.

mglae's post #12's link to a solution worked for me; I just changed "exec /bin/sh" to "exec /bin/bash" but followed the other instructions to the letter. Thanks!

frakkin64's ping idea: duh, again, I use it to find computers that come online, so I could have used it for computers going offline/powering down too.

ghtester, thanks, I had considered a 433MHz transmitter in the Pi and power sockets as a potential follow-up to this, but that's another subject for another time.

Thank you all!

Hey frakkin64,

Thanks for that.

In the end it was actually quite straight forward following the link from mglae, even for someone who does not know much at all about the inner workings of Linux.