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From: omh@brunix (Owen M. Hartnett)
Newsgroups: comp.sys.mac.programmer,comp.sys.mac
Subject: Re: DTS and Compatibility (Was: MF)
Message-ID: <5776@brunix.UUCP>
Date: 6 May 89 03:16:58 GMT
References: <1562@neoucom.UUCP> <28399@apple.Apple.COM> <3637@brunix.UUCP> <1304@internal.Apple.COM> <3918@brunix.UUCP> <1460@internal.Apple.COM>
Sender: news@brunix.UUCP
Reply-To: omh@zaphod.UUCP (Owen M. Hartnett)
Organization: Brown University Department of Computer Science
Lines: 35

In article <1460@internal.Apple.COM> lsr@Apple.COM (Larry Rosenstein) writes:
>In article <3918@brunix.UUCP> omh@brunix (Owen M. Hartnett) writes:
>> Maybe I'm wrong, but if you put up a standard, particularly on an issue
>> as clear cut as this: (0=computer running finder, 1=computer running
>> multi-finder, 2=computer running a/ux, 3 = computer running ???), you
>> will nip a lot of compatibility problems in the bud.
>
>I'm not so sure.  We have a similar mechanism in SysEnvirons to 
>determine what CPU you are running on (68000, 68020, 68030, ...) and what 
>model (Mac II, Mac IIx, etc.).   So what happens?  Some applications check 
>for color capability by seeing if they are running on a 68020 or on a Mac 
>II, even though SysEnvirons tell you if Color Quickdraw is available.  

Bad programmers who ignore obvious warnings like those in SysEnvirons are going
to write poor code, no matter what information Apple withholds.

The Real question is:

At what point does useful information become "bad," that is where knowledge
by the programmer community is at direct odds with the goals of Apple 
Development.  It is a noble goal that Apple DTS wants every application written
to run transparently under Multi and Unifinder, but what
about the developer who wants his application to run *only* under Multifinder?

He encounters a set of deliberate hurdles.  My premise is that this is counter
productive - developers should be given a way to write exceptional applications.

When you think about it, the Mac is the only machine where the application has
no idea of what Operating System is underneath it.

-Owen
Owen Hartnett
Brown University Computer Science

omh@cs.brown.edu.CSNET