Path: utzoo!utgpu!jarvis.csri.toronto.edu!clyde.concordia.ca!uunet!tut.cis.ohio-state.edu!zaphod.mps.ohio-state.edu!van-bc!rsoft!mindlink!a464
From: a464@mindlink.UUCP (Bruce Dawson)
Newsgroups: comp.sys.amiga.tech
Subject: Re: Mutual Exclude Gadgets
Message-ID: <861@mindlink.UUCP>
Date: 28 Dec 89 20:56:40 GMT
Organization: MIND LINK! - British Columbia, Canada
Lines: 38


     Hmmm.  If I were an Amiga programmer (and I am) and I bought Lattice C 5.0
(and I did) and I read the intuition.h include file (and I did) I would get the
impression that the mutual exclude field is there, works, and should be used.
The include file spends ten lines explaining exactly how mutual exclude works,
in excruciating detail, without ever mentioning that the function doesn't work
at all.

     I suppose this might be Lattice's fault, but I doubt it.

     Basically, this is ridiculous.  Ignoring for a moment the issue of what
the developer can do after he finds out (somehow) that MutualExclude doesn't
work, there is a separate issue here of extremely misleading documentation.
Unless you want to make it a requirement that anybody who wants to do any Amiga
programming at all must read every single manual, autodocs, AmigaMail etc.
before writing the first line of code, you should get rid of that misleading
description.  Over the years I have heard a great number of people ask 'Why
can't I get MutualExclude to work' and I'm really surprised that it's _still_
documented as working!

     Back to the main issue:  Given the documentation in the include files
(there may be more, but you're crazy if you think that all programmers read all
of the documentation) it would seem to me that a significant percentage of
programmers will use this field to implement there own mutual exclusion.
Perhaps we could get a professor of semantics to decide whether this is correct
or not, but the bitter reality is that there MUST already be enough programs
out there using that field that you can not safely start using it yourself in
an incompatible way without breaking more innocent programs than you have any
right to.

     I agree with Larry.  Until the include files have been changed to
specifically say that the field is reserved and announcements have been made in
as many places as possible (since not everybody is going to read the include
files and look for changes) and a couple of years have been waited, you're
risking a lot of very ugly gadgets if you implement that field in an
incompatible way.

.Bruce.