6.1 Interfacing with UNIX

Question: [UNIX]

How can I turn a Prolog source file into a UNIX script, to be invoked from the command line or from a Web application, for example?

Wrap the file into an executable Shell script that simply invokes SICStus. Informational messages can be filtered out by redirecting stderr to /dev/null. For example:

     #!/bin/sh
     exec sicstus 2> /dev/null -f -a "$@" <<EOF
     
     % Tell SICStus to consult the sources.
     % The embedded command invokes main(Args)
     % where Args is the script's arguments passed as a list of atoms.
     
     [user].
     
     main(Args) :-
         format('Hello world!\n\c
                 Invoked with args = ~q\n', [Args]).
     
     :-
     	prolog_flag(argv, Args), main(Args).
     EOF

The above script can be invoked as follows:

     % ./hw.sh a 236U ka=ka
     Hello world!
     Invoked with args = [a,'236U','ka=ka']