Mini Shell

% Copyright (C) 2001-2019 Artifex Software, Inc.
% All Rights Reserved.
%
% This software is provided AS-IS with no warranty, either express or
% implied.
%
% This software is distributed under license and may not be copied,
% modified or distributed except as expressly authorized under the terms
% of the license contained in the file LICENSE in this distribution.
%
% Refer to licensing information at http://www.artifex.com or contact
% Artifex Software, Inc.,  1305 Grant Avenue - Suite 200, Novato,
% CA 94945, U.S.A., +1(415)492-9861, for further information.
%

% Trace individual operators or procedures.
% <opref> is <opname> or <opname> <dict>
%    (dict defaults to dict where op is currently defined, if writable;
%    otherwise uses userdict)
% <opref> traceop prints vmem usage before;
% <opref> <numargs|preproc> prints arguments or runs proc before;
% <opref> <numargs|preproc> <numresults|postproc>
%    also prints results or runs proc after.
% If traceflush is true, flush the output after each printout.
/traceflush true def

currentpacking true setpacking
currentglobal true setglobal

% Define the default "before" action
/tracebefore { vmstatus 3 traceprint pop pop pop } def

% Define the default "after" action
/traceafter { } def

/traceprint {
  dup type /integertype eq {
    1 sub -1 0 { ( ) print index ==only } for
  } {
    exec
  } ifelse
} bind def
/traceend {
  traceflush { flush } if
} bind def
/traceop {
  userdict begin
  dup type dup /nametype eq exch /dicttype eq or { { tracebefore } } if
  1 index type dup /nametype eq exch /dicttype eq or { { traceafter } } if
  /.tpost exch def /.tpre exch def
  dup type /dicttype ne {
    dup where not { userdict 1 index {} put userdict } if
  } if
  dup dup wcheck not {
    (Warning: substituting userdict for non-writable dictionary.) =
    pop userdict
  } if
  /.tddict exch def   /.tdict exch def   /.tname exch cvlit def
  currentglobal [
  .tname /=only cvx ( ) /print cvx
    /.tpre load /traceprint cvx /traceend cvx
    .tdict .tname get /.tdef 1 index cvlit def
    dup xcheck {
      dup type dup /arraytype eq exch /packedarraytype eq or {
        /exec cvx
      } if
    } if
    /.tpost load /traceprint cvx () /= cvx /traceend cvx
  .tdef gcheck /.tpre load gcheck and /.tpost load gcheck and setglobal
  ] cvx
  .tdef type /operatortype eq {
    .tname exch .makeoperator
  } if
  exch setglobal
  .tddict exch .tname exch put
  end		% userdict
} bind def
/tracebind /bind load def	% in case someone wants to put it back
/bind { } def		% disable

setglobal
setpacking