Path: utzoo!attcan!utgpu!jarvis.csri.toronto.edu!mailrus!ames!apple!claris!peirce
From: peirce@claris.com (Michael Peirce)
Newsgroups: comp.sys.mac
Subject: Re: Real Multifinder (was Re: Hey Apple Mac engineers...)
Message-ID: <10520@claris.com>
Date: 1 Sep 89 18:06:08 GMT
References: <46100321@uxe.cso.uiuc.edu> <1989Aug15.001507.14552@sj.ate.slb.com> <24626@iuvax.cs.indiana.edu> <3997@internal.Apple.COM> <738@eplrx7.UUCP>
Reply-To: peirce@claris.com (Michael Peirce)
Distribution: usa
Organization: Claris Corporation, Santa Clara CA
Lines: 43

In article <738@eplrx7.UUCP> leipold@eplrx7.UUCP (Walt Leipold) writes:
>In article <3997@internal.Apple.COM> Larry Rosenstein writes:
>>It is possible to work under MultiFinder without writing any extra code, 
>>although by writing some MultiFinder-specific code you can make the system 
>>operate more smoothly.
>
>I've been watching this thread for a week or so, and have to disagree
>(partially) with the above.  The original question appeared to refer to
>the amount of extra code you'd need to add to a Unix-style program
>(which gets backgrounding for free) to get it running in the background
>on the Mac.  This is not just a matter of adding some Multifinder-
>specific code.  Instead, you have to add an entire event loop to the
>program to allow Multifinder to timeslice it.  And quite often, a
>program's original (hopefully) clean structure (the case for most
>Unix filters) is badly corrupted by contorting it to fit an event loop.
>
>-- 
>"As long as you've lit one candle,                         Walt Leipold
>you're allowed to curse the darkness."       (leipolw%esvax@dupont.com)
>--

If you really wanted to port a Unix style filter program to the Mac the 
easiest way to do so is to make it into a MPW tool.  These programs can
use simple printf and getch style i/o without change.  And to get these
to work with MultiFinder is trivial.  Simply sprinkly a few calls to SpinCursor
in places where lots of processing is taking place and you're all set. 

This approach doesn't lead to "badly corrupted" code with event loops, just
a few extra calls that can be #IFDEF'ed in.  

Porting Unix tools to the Finder environment is probably a waste of time, the
two environments have too different a view on how the world looks.  But 
porting Unix tools to the MPW environment can be quite easy and rewarding.

Claris Corp. | Michael R. Peirce
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