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From: cmcmanis@stpeter.Sun.COM (Chuck McManis)
Newsgroups: comp.sys.amiga.tech
Subject: Re: Locks and resources (was path-list stuff)
Message-ID: <130652@sun.Eng.Sun.COM>
Date: 24 Jan 90 20:20:01 GMT
References: <130545@sun.Eng.Sun.COM> <13041@cbnewsc.ATT.COM>
Sender: news@sun.Eng.Sun.COM
Reply-To: cmcmanis@sun.UUCP (Chuck McManis)
Organization: Sun Microsystems, Mountain View
Lines: 36

In article <13041@cbnewsc.ATT.COM> (gregg.g.wonderly) writes:
> ... It would have really been trival for Commodore to do this from 
> the start.

Think again. It isn't trivial, (let's here how you would do it in 1000
words or less) and 90% of the time the cost in terms of extra code isn't
worth the hassle. You have to remember the entire Amiga kernel, some 
supporting libraries and a couple of device drivers fits into 256K of
ROM. Compare and contrast how this would effect performance of simple
routines versus making sure routines that care are accurate.

>I guess that what I am asking is why can't Amiga Dos have all of the nice
>attributes of UN*X resource control and still have the other functionalities
>that it has now?  I really don't see why it doesn't nor why it can't!

Because it was written with different design constraints. Those contraints
were tight code, minimalist system intervention between you and the hardware,
and no MMU. Fortunately, you can buy UNIX soon for the 2500 and then you
won't have to worry about any of this anymore. Of course you might find
a marked slowdown in the performance of your system. UNIX has it's uses,
in real life I help design it, but it is not necessarily the OS of choice 
if you are building a resource constrained machine.

You might as well ask your self, "Why can't my Hyundai Excell have the
features and performance of the BMW 700 series?" The answer is, it can
with a lot of work and effort, but you would end up spending more for
it than if you bought the BMW outright. Same thing with AmigaDOS, it is
nontrivial but you could give it all the features of UNIX. But if that
is what you wanted, why didn't you buy it in the first place? (comments
about UNIX not being for sale at this time are noted. You could always
buy a Sun instead :-))

--Chuck McManis
uucp: {anywhere}!sun!cmcmanis   BIX: cmcmanis  ARPAnet: cmcmanis@Eng.Sun.COM
These opinions are my own and no one elses, but you knew that didn't you.
"If it didn't have bones in it, it wouldn't be crunchy now would it?!"