Allow custom startup scripts that survive an upgrade (for external developers).

[izak]

When advanced users customise the CCGX with their own software, this is overwritten whenever the venus image is updated. Though the developer can store his software on the /data partition to survive updates, startup scripts the developer might have put in place won't.

[izak]

Initial implementation, open for comments/criticism.

[oldwindmill]

I'm just a solution architect, not a developer.. But, when I first saw the issue posed, my immediate thought was to call an install time script which would check for the presence of a file in /data, and similarly on start up.
Presumably, a new service could be implemented via an install script which creates a symlink into /etc/service from a users installation in say /data/user/service
For consistency, a 'style guide' or set of common patterns would be great...
So, Izak's approach works for me..

[izak]

The idea was literally to follow a style similar to Debian's /etc/rc.local. The only additional requirement was that you could also hook early functionality (before the network comes up), so there is two scripts: rcS.local and rc.local, the former runs right at the end of startup scripts, and the latter runs after the rest of the services has started. You can indeed do anything you want here, including creating the required symlinks to start a service, install a cron job, or whatever your heart desires.

[mpvader]

Added in Venus v2.12~1

victronenergy/meta-victronenergy@2dbd16c

victronenergy/meta-victronenergy@b3ac89c