If you are using Windows, the batch file
runtime-directory\qpvars.bat needs to be executed to set up
the necessary environment variables. If you are using UNIX, your
PATH environment variable needs to include the directory
containing the Quintus tools.
To start Prolog, type prolog at the operating system prompt (whether UNIX or Windows):
% prolog
The system responds by displaying a copyright message followed by the main Prolog prompt, as shown below.
Quintus Prolog Release 3.5 (Sun 4, SunOS 5.5)
| ?-
The | ?- is the main Prolog prompt. It indicates that you
are at the top level of the Prolog system. At this point, the system
is waiting for you to type a goal, such as a command to load a
previously created file containing a Prolog program.
If you are using Windows, it is probably more useful to run qpwin
from the Start Menu. This has the same appearance as the
console-based version, except that the output is directed to a window.
The properties of this window can be tuned; see too-too-prolog.
If you use qpwin you do not need to run the
runtime-directory\qpvars.bat batch file.