Simple SMS tool (using ModemManager)

I’ve searched in many places for a tool to handle SMS messages (sending, receiving, …) using ModemManager - but couldn’t find one, so I wrote a quick and dirty Bash script that does so. I have a failover setup for my main internet provider using an LTE modem and found it very useful to have a mobile number available for sending SMS alerts when server errors occur, such as: no internet connection —…