By default, SWI-Prolog is installed as `swipl'. The command line arguments of SWI-Prolog itself and its utility programs are documented using standard Unix man pages. SWI-Prolog is normally operated as an interactive application simply by starting the program:
$ swipl Welcome to SWI-Prolog ... ... 1 ?-
After starting Prolog, one normally loads a program into it using consult/1, which may be abbreviated by putting the name of the program file between square brackets. The following goal loads the file likes.pl containing clauses for the predicates likes/2 :
?- [likes]. true. ?-
Alternatively, the source file may be given as command line arguments:
$ swipl likes.pl Welcome to SWI-Prolog ... ... 1 ?-
After this point, Unix and Windows users unite, so if you are using Unix please continue at section 2.1.2.