Resolving Path

[sevens]

So I've recently decided to make some poor decisions and try to make a terminal based mod manager that at least somewhat resembles the in-game one, because I figure it'd be nice to have and getting it to work would be pretty darn neat. I'd like to do my best to avoid having the user point the program in 20 different directions to access the info I need, so I'm wondering if there's a way to go from the application directory to the user data directory. Is this over the top levels of abstraction? Yes! It absolutely is! So glad you noticed, but unfortunately the java dev in me craves it desperately so... here I am asking whether that's possible in some obscene twist of fate. I'd assume it is in some capacity, given that the factorio executable itself has to make that leap, but I don't know if the information it uses to get there is available to an external program.
Any help would be greatly appreciated, even a quick "yeah, that's absolutely not worth the trouble" works wonders.

[sevens]

More specifically, I think, I want to resolve the __PATH__[...]__ variables that appear in the config files, as that would allow me to go from the app directory, to the config directory, to the data directories, which basically gives me every bit of information I need

[sevens]

After a bit of poking around, it doesn't seem as though it's possible for an external program... darn :/
oh well, was worth a shot