Relay-Version: version B 2.10 5/3/83; site utzoo.UUCP Path: utzoo!utgpu!water!watnot!watmath!clyde!rutgers!mit-eddie!genrad!decvax!ucbvax!ENEEVAX.UMD.EDU!hsu From: hsu@ENEEVAX.UMD.EDU.UUCP Newsgroups: mod.computers.68k Subject: Re: 68000 O/S's, MMUs, et. al. Message-ID: <8702190305.AA02511@eneevax.umd.edu> Date: Wed, 18-Feb-87 22:05:52 EST Article-I.D.: eneevax.8702190305.AA02511 Posted: Wed Feb 18 22:05:52 1987 Date-Received: Fri, 20-Feb-87 04:12:14 EST References: <8702181533.AA27804@ucbvax.Berkeley.EDU> Sender: mwm@ucbvax.BERKELEY.EDU Organization: The Royal Maryland Ice Cream Consumption Laboratory Lines: 70 Approved: info-68k@ucbvax.berkeley.edu In article <8702181533.AA27804@ucbvax.Berkeley.EDU> Robert Heller writes: >It seems that my recent message stirred up some dust. First of all let me >clarify a few things. > >First of I don't object to having a MMU. It is just that I don't think a >MMU is *neccessary* for *most* applications. In a development/hacker >environment and with real milti-user systems it is needed. Today, these points appear to be true. > It is doubtfull >that MMUs will ever be common on *little* home/office systems (i.e. ST's, >Amiga's, Mac's etc.) - most of these system will be running well behaved >software (i.e. canned business and home software), so these system can >easily get by with an unprotected multi-tasking O/S (like OS9 or AMIGADOS). This, however, is a truly remarkable if not wholly ridiculous claim. MMU's are coming, whether you like them or not. Both Motorola's and Intel's latest offerings have them built in, and in a sense, the iAPX86 family has always had them. Also remarkable is this concept of "well- behavedness"; having spent some years in a software store, I can assure you that few programs are "well-behaved" out of the box, at least for the first year. Often longer. An unprotected multitasking system is only as safe as its most dangerous process, and I for one don't intend to restrict myself to one-vendor canned packages. This is the sort of mentality that breeds dead-end products. "Simpler systems tend to run simpler software." >I really doubt that UNIX/MINIX will ever be the O/S of choice amongst home >and office users: UNIX is just too "weird" (why is the directory command >"ls"? why is the type command "cat"? what is an inode? - only UNIX hackers >really understand UNIX). Honestly, you should have attended the Winter USEnix conference. "ls" is no weirder than "dir" or "catalog". Hell, you should have seen the fuss I made when I discovered that nobody's BASIC implementation used "scr" anymore; they all had this thing called "new". "cat", like most other Unix commands, is either an abbreviation or an acronym. Yes, it's terse, but you at least have the ability to redefine everything to your heart's content with the shell's alias mechanism. And nobody needs to know about inodes anymore than you need to know about VTOCs or FATs or whatnot. >Secondly, I have found that I have had little or no trouble with runaway >pointers totally trashing the system, at worst it just trashes the current >"process". Re-booting just that process is suffientent. I guess I tend to >write good code. Also, I have little need to run jobs in the background >much. I guess I am just a synchronious user. Either that, or you tend to write uncomplicated code. That you can detect the trashing is quite remarkable in itself; how do you know it's not subtly wrecking something else very quietly? >I have used UNIX a little and have *not* liked it at all. The documentation >tends to be poor and the error messages not very informative. >... > Robert Heller While the Unix documentation is cryptic to most (if not all) beginning users, the strength of Unix lies in its flexible and relatively consistent command interpreter. Most of the mysteries go away once you get the hang of the piping output through filters. And the quality and breadth of the tool assortment is unrivaled. The tutorials probably could stand to be simplified. -dave -- David "bd" Hsu hsu@eneevax.umd.edu seismo!mimsy!eneevax!hsu EE Computer Facility, Maryversity of Uniland, College Park, MD 20742