Xref: utzoo comp.arch:16116 comp.os.misc:1186 Path: utzoo!utgpu!news-server.csri.toronto.edu!clyde.concordia.ca!uunet!sco!seanf From: seanf@sco.COM (Sean Fagan) Newsgroups: comp.arch,comp.os.misc Subject: Re: Macintosh OS (was: 68000 and Workstations.) Message-ID: <6392@scolex.sco.COM> Date: 28 May 90 01:08:29 GMT References: <30273@ut-emx.UUCP> <76700207@p.cs.uiuc.edu> <1990May24.114553.10301@phri.nyu.edu> <37@voa3.UUCP> <402@newave.UUCP> <26200.265dd7be@vaxb.acs.unt.edu> Sender: news@sco.COM Reply-To: seanf@sco.COM (Sean Fagan) Followup-To: comp.os.misc Organization: The Santa Cruz Operation, Inc. Lines: 51 (Note the followup...) In article <26200.265dd7be@vaxb.acs.unt.edu> ac08@vaxb.acs.unt.edu writes: >Gee, that's cute. >But according to your definitions, there is no such thing as an "operating >system" on any computer ever made... after all, they're just a bunch of >programs that talk to each other, right? >And UNIX even more so... since most UNIX users I know tend to treat commands >as programs... :) No. They are a bunch of programs that talk to the kernel far more often than they talk to themselves (generally). Also, please read the article again. He said "procedures," not programs. Yes, Virginia, there *is* a difference. Most people consider that a *true* OS has protection of some sort; that is, some way of making sure that programs don't step on each other and can live in peace and harmony. (Sometimes, this is done just to make sure that the program doesn't step on the OS, true, but it's still nice to be there 8-).) Ask yourself this: using your "OS," following all of the rules, is it possible to write a program that will lock up the machine? On the Mac, I think it is, under MSDOS it certainly is. On the Amiga, I don't think it is, because the rules they laid down were oriented towards multitasking instead of rapid screen update. Yet the Amiga doesn't have an MMU, just like the Mac. Which one has the OS, then? >So- for your next trick, are you going to prove black is white, or that >1 + 1 = 3? No, the next trick would be to make sure that people take an OS course before defining what an OS is. That's going to be very, very hard, though, I think. >[Written with more than a little tongue in cheek... the Mac OS is more of >an operating "system" than most, since it *does* have a fairly firm set of >rules, as opposed to most machines, which have few outside of the coding of >the ROMS and the CPU...] Huh? The Mac, last time I checked, had a lot of routines a programmer could use, some of which were in ROM, others in RAM, but not much else. I have never, for example, seen something that said "do not modify the Status Register" (N.B.: It's been a while, I'll admit, and I may have missed it. If so, I'd be glad to hear about it). -- -----------------+ Sean Eric Fagan | "It's a pity the universe doesn't use [a] segmented seanf@sco.COM | architecture with a protected mode." uunet!sco!seanf | -- Rich Cook, _Wizard's Bane_ (408) 458-1422 | Any opinions expressed are my own, not my employers'.