Just curious if there is any prior art for automatic startup script, say with Raspbian systemd?
Currently I’m just sticking
/usr/local/bin/hologram modem connect
in /etc/rc.local then testing if a ping works before starting up my application.
I am pretty sure that you can write an /etc/init.d script. Look in that folder for examples.
I question if that’s what you really want to do.
I prefer to call from within the application.