Usage:
Arg is get_program_argument(N)

Gets the N-th argument passed to the executing program (N=0 is the program name (strawberry) , N=1 is the prolog file (test.pro), N=2 is the first argument passed to the prolog file, etc). Fails if there is no such argument

N - an integer number representing the corresponding
argument passed to the prolog program
 

Examples:

 ./strawberry test.pro "First Arg" "Second Arg"

?- Arg is get_program_argument(2),
write(Arg). % First Arg