Joe,

Its the raspbian version that comes with noobs v3.2.0.  Not sure which
version it is.  No idea how to check that.

> man chkconfig

No manual entry for that available.

> just plunk the script into the proper rc.[012345] directory

I have /no/ idea what would be proper or impoper about those folders.  For
that I would need to have some more information about their purposes ...


> Web search "BEGIN INIT INFO" comes up with useful things

Grumble ...   I should have thought of that.

> https://refspecs.linuxfoundation.org/LSB_1.2.0/gLSB/initscrcomconv.html
> http://refspecs.linuxbase.org/LSB_3.0.0/LSB-PDA/LSB-PDA/
> initscrcomconv.html
> https://www.thegeekstuff.com/2012/03/lsbinit-script/

Allo of those stop exactly where my question starts: What is a
"boot_facility_" or "run_level_" ?   Which one(s) should my script have, and
most importantly, why ?

Before posting here I also found the below one, but it suffers from the same
problem as the ones you found:
https://wiki.debian.org/LSBInitScripts

Regards,
Rudy Wieser

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