[comp.sys.acorn] PostScript printer driver problems

mrp@minster.york.ac.uk (03/11/91)

I use Acorn's Postscript printer driver, and I have edited the
PSprolog file (under instructions from Computer Concetps) so it can
translate the MathGreek font into Symbol.  When I printed (from
Impression) to a file and transfered the file onto our network and
tried to print it on both an Apple Laserwriter and and Imagen it gave
me the following message:

	%%[ Error: typecheck; OffendingCommand: copy ]%%

(In fact all our utilities and hardware that interpret postscript give this
error) 

As an attempt at solving this I commented out the offending line and
both printers produced the page OK.  The page contained lots of fonts
including MathGreek and a draw file.  The bit I edited was:

/fonts 100 dict def
/ChkCh {
  dup Encoding exch get
  CharStrings exch known {pop} {Encoding exch /.notdef put} ifelse
} bind def
/FF {
  3 1 roll
  findfont begin
    currentdict dup maxlength 1 add dict begin
      {1 index /FID ne {def} {pop pop} ifelse} forall
%      /Encoding 3 -1 roll 256 array copy def            -- this line altered 
      /Metrics 1 dict def
      Metrics /.notdef 0 put
      0 1 255 /ChkCh load for
      dup currentdict
    end
  end
  definefont
  fonts 3 1 roll put
} bind def


( This text appeared in the original PSprolog file before I edited it, so 
I don't think the CC stuff is to blame.  But I could be wrong :-) )

So the questions are: what does this line do?, does removing it do any harm 
and if not why was it there in the first place?

   - Martin

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| Martin Portman                | Phone: (0904) 432735                      |
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