/usr/share/Yap/pl/protect.yap is in yap 5.1.3-6.
This file is owned by root:root, with mode 0o644.
The actual contents of the file can be viewed below.
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 | /*************************************************************************
* *
* YAP Prolog *
* *
* Yap Prolog was developed at NCCUP - Universidade do Porto *
* *
* Copyright L.Damas, V.S.Costa and Universidade do Porto 1985-1997 *
* *
**************************************************************************
* *
* File: protect.yap *
* Last rev: *
* mods: *
* comments: protecting the system functions *
* *
*************************************************************************/
% This protects all code from further changes
% and also makes it impossible from some predicates to be seen
'$protect' :-
current_atom(Name),
atom_codes(Name,[0'$|_]),
'$hide_predicates'(Name),
'$hide'(Name).
'$protect' :-
'$hide_predicates'(bootstrap),
'$hide'(bootstrap).
'$protect'.
'$hide_predicates'(Name) :-
'$current_predicate_for_atom'(Name, prolog, P),
'$hide_predicate'(P,prolog),
fail.
'$hide_predicates'(_).
% hide all atoms who start by '$'
'$hide'('$VAR') :- !, fail. /* not $VAR */
'$hide'('$dbref') :- !, fail. /* not stream position */
'$hide'('$stream') :- !, fail. /* not $STREAM */
'$hide'('$stream_position') :- !, fail. /* not stream position */
'$hide'('$hacks') :- !, fail. /* not stream position */
'$hide'(Name) :- hide(Name), fail.
|