A wrapper for the depreciated gatttools cli on rasperry pi (tested pi 3b v1.2 / Raspbian GNU/Linux 10 (buster)) for interfacing with a Renogy RBT100LFP12S 12v, 100Ah LiFePO4 battery.
'main.cpp' contains a very basic example which can be compiled with;
$ sudo g++ test main.cpp
$ ./test