How to get something to start on next startup only one time in Haiku

Question

I want to make something start up after the next reboot, but only once, and not after any other reboot. Just like your first boot of a Haiku image off a USB stick runs the Installer, and whether you use it or not (maybe you just want to always run it off the stick, for instance) it never runs on startup after that. How can I do something like that, like a one-time reminder for next bootup?

If I mount a freshly downloaded image and compare the following directories in it to my installed boot drive:

/image/home/config/boot
/image/system/boot
/image/common/boot

...the files are identical. So how does Haiku know whether the run-once installer has been run? Not from there, anyway...

Update: I did find the file /image/common/settings/fresh_install that did not exist on my install, containing the text "This file is only supposed to exist on fresh Haiku installations." However, copying it to my install and rebooting only resulted in the MIME type updater running again, not the installer.

Answer 1

Make sure /boot/common/settings/fresh_install exists and then create a shell script ending in .sh in /boot/common/settings/boot/post_install. It will run on the next startup, and then fresh_install will auto-delete itself, causing the shell script not to run on subsequent startups.

I guess that approach could have been taken from the start, but maybe this is better because it's "built in"? Basically you can steal the following code from /boot/system/boot/Bootscript to accomplish the same thing with a different file than fresh_install, non-.sh scripts, etc. if you want to tweak it:

# Check for fresh install and run post install scripts.
freshInstallIndicator=/boot/common/settings/fresh_install
postInstallDir=/boot/common/boot/post_install
if [ -e $freshInstallIndicator ]; then
    # wait a moment for things to calm down a bit
    sleep 3

    # execute scripts
    for f in $postInstallDir/*.sh; do
        if [ -f $f ]; then
            echo "Running post install script $f ..." > /dev/dprintf
            $f
        fi
    done

    sync
    rm $freshInstallIndicator
fi

...and put it in your UserBootScript, for example.

(Still not sure what makes the installer itself run--it must be an even more special case, because it launches before Deskbar or Tracker start up.)