Executing prolog queries from shell

Hello everyone.

I started building the left hemisphere of my robot's brain with gprolog and I'm stuck on probably a very basic thing as I haven't touched prolog since uni. I want to execute/pass/pipe/whatever queries/code into prolog from the GNU/Linux shell and save/use the results. Like friends(bob,alice) to see if they are friends or whatever. I can run any shell command via python or the shell itself of course but what/how should I run (sysntax) to e.g. have gprolog use a specific file with my stored rules or whatever (complied I guess) and pass the query like an argument or input? Actually, is this possible at all?

I hope I didn't confuse you!


Thank you,

Antonios A.