Path: utzoo!utgpu!news-server.csri.toronto.edu!rpi!usc!cs.utexas.edu!sun-barr!apple!keith
From: keith@Apple.COM (Keith Rollin)
Newsgroups: comp.sys.mac.programmer
Subject: Re: Has AppleSoundChip? Gestalt? How?
Message-ID: <51491@apple.Apple.COM>
Date: 13 Apr 91 20:52:36 GMT
References: <1991Apr9.011011.29542@kuhub.cc.ukans.edu> <24147@well.sf.ca.us> <1991Apr12.182621.10184@ida.liu.se>
Organization: Apple Computer Inc., Cupertino, CA
Lines: 31

>smoke@well.sf.ca.us (Nicholas Jackiw) writes:
>
>>I love this stuff.  With the new edition manager, or any other OS package
>>that requires initialization, you now have to write code that checks to
>>see (TrapAvailable) whether you can check to see (Gestalt) whether you
>>can check to see (InitEditionMgr) whether you can use editions.  

This is not quite true. Gestalt is implemented as glue in both the
latest MPW and THINK environments. This means that you do NOT have to
call some sort of TrapAvailable routine in order to call Gestalt. As
long as you have the latest development systems, you can just call it.

The Gestalt glue, in turn, makes its own check to see if there is a
version of Gestalt installed in the ROMs or by the System. If so, the
glue forwards to those routines. Otherwise, it does as best as it can
by itself, providing pretty much the same information as the
SysEnvirons call.

If you have a better idea on how Apple can provide new functionality
and maintain flexibility without requiring programs to make these
checks, let us know. (BTW: there is an answer to this challenge... use
MacApp 3.0 when it comes out later on this year. It does all this
checking for you! This announcement paid for by the Happy MacApp
Programmers of the World Committee.)

-- 
------------------------------------------------------------------------------
Keith Rollin  ---  Apple Computer, Inc. 
INTERNET: keith@apple.com
    UUCP: {decwrl, hoptoad, nsc, sun, amdahl}!apple!keith
"But where the senses fail us, reason must step in."  - Galileo