Path: utzoo!attcan!uunet!zephyr.ens.tek.com!uw-beaver!ssc-vax!uvicctr.UVic.CA!marykuca
From: marykuca@uvicctr.UVic.CA.UUCP (Brent Marykuca)
Newsgroups: comp.sys.mac.programmer
Subject: Re: CDEV/INIT Data Exchange, another way
Summary: Why not use Gestalt?
Message-ID: <1121@uvicctr.UVic.CA.UUCP>
Date: 7 Jun 90 20:05:55 GMT
References: <55045@microsoft.UUCP> <1990Jun5.142604.11826@asterix.drev.dnd.ca> <8560@goofy.Apple.COM> <1990Jun6.163604.12918@murdoch.acc.Virginia.EDU>
Reply-To: marykuca@uvicctr.UVic.CA.UUCP (Brent Marykuca)
Organization: University of Victoria, Victoria B.C. Canada
Lines: 21

It seems to me that all this kludgy-sounding passing around of resources
and testing for "magic strings" can be eliminated fairly easily by using
the Gestalt Manager, which can be found in all Macintosh systems after
6.0.4, and in glue form in MPW 3.2.  Have the INIT use NewGestalt to install
a new Gestalt selector function which returns a pointer (or handle, or
whatever is required) to the data to be exchanged.  Then have the cdev
call Gestalt to pick up the handle.  If the INIT hasn't been loaded, then
Gestalt will return an error.  This seems clean (no prefs file cluttering   
up your System Folder, no validity checking to do on the resource if it
is there) and compatible.

About the only thing that I can see that is wrong with this approach
(and if I've missed anything, I'm certain that somebody will point it
out) is that Gestalt is supposed to be used for feature testing, not
as a mailbox for data.  

Cheers,

Brent Marykuca
Computing User Services
University of Victoria