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From: dplatt@ntg.com (Dave Platt)
Newsgroups: comp.protocols.appletalk
Subject: LaserWriter 7.0 vs. LaserWriter 6.1 vs. lwsrv
Message-ID: <462@goblin.ntg.com>
Date: 15 May 91 22:57:17 GMT
Organization: New Technologies Group, Palo Alto CA
Lines: 36

I just tried using LaserWriter 7.0, with the CAP 6.0 software patched up
through #15, and an initial collection of procsets captured from
LaserWriter 6.1.  Sigh... doesn't work properly... the job aborts
without printing anything, due to a missing command "sgd".

It seems that between LaserWriter 6.1 and LaserWriter 7.0, Apple has
made some changes in the driver and its dictionary, so that the 6.1
driver's output won't work with the 7.0 driver's prep-file or vice
versa.  This would not be a problem for lwsrv, EXCEPT THAT APPLE DID NOT
CHANGE THE APPLEDICT REVISION NUMBER!  [pardon me for shouting... I'm a
bit annoyed.]  Both of these prep-files describe themselves as being
"appledict 71 0", and yet they are different and mutually incompossible.

Sigh again.  I'm rapidly coming to the conclusion that lwsrv's handling
of the LaserPrep file... which was both necessary and sufficient for the
LaserWriter 5.2 driver and its earlier cousins... is _neither_ necessary
nor workable in the New Era of non-persistent prep-files.

It's no longer really necessary to strip out the prep-file transmitted
by the LaserWriter driver, hand-edit it to remove the "exitserver"
coding, and automagically reinsert the edited version on-the-fly when
spooling a job.  There's no longer any "exitserver" code in the main
prep-file... and we apparently cannot depend upon Apple to disambiguate
different versions of the prep-file by changing the revision number when
compatibility is lost.

So... I think I'll see if I can work up a new set of patches to lwsrv,
which will simply allow newer versions of AppleDict (>= 71) to pass
through unmodified.



-- 
Dave Platt                                                VOICE: (415) 813-8917
              Domain: dplatt@ntg.com      UUCP: ...apple!ntg!dplatt
 USNAIL: New Technologies Group Inc. 2468 Embarcardero Way, Palo Alto CA 94303