During development of applications involving both Prolog and foreign
code, it can be very useful to build a stand-alone program that
includes QUI. This way, you can use the QUI debugger for stepping
through the Prolog code and a standard debugger such as gdb(1)
for stepping through the foreign code.
A good way to do this is to create a file qui.pl
containing just the one
line:
:- ensure_loaded(library(qui)).
This should then be compiled to QOF in the normal way and linked into your application. For example:
% qpc -D <application files> qui.pl
Then start up the resulting executable file using a command such as
% gdb a.out
See fli-p2f-fcr for information about using a standard debugger in conjunction with a Prolog executable file.
Please note: The reason for putting the
ensure_loaded
command in a file by itself, rather than including it in your application code, is that it will not work if executed in an ordinaryprolog
system that does not include QUI; it is not possible to load QUI dynamically.