Path: utzoo!attcan!uunet!husc6!think!ames!lll-tis!lll-winken!abhg!carpet!bill From: bill@carpet.WLK.COM (Bill Kennedy) Newsgroups: comp.sys.att Subject: Re: DOS Tasks under Unix: Let's hear about it! Summary: NOT Locus/Microport Keywords: DOS multitasking unix Message-ID: <69@carpet.WLK.COM> Date: 21 May 88 17:39:27 GMT References: <5090@ecsvax.UUCP> <1791@cuuxb.ATT.COM> Reply-To: bill@carpet.UUCP (Bill Kennedy) Followup-To: comp.sys.att Distribution: na Organization: W.L. Kennedy Jr. and Associates Lines: 113 In article <1791@cuuxb.ATT.COM> mmengel@cuuxb.UUCP (PUT YOUR NAME HERE) writes: >In article <5090@ecsvax.UUCP> gas@ecsvax.UUCP (Guerry A. Semones) writes: >>Okay folks, AT&T's 386 based unix for their work group series has >>been available for a short while. Sun has announced and begun to [ lots deleted about VP/ix, I am following up for Microport Merge/386 ] >> Thanks in advance for your insights.... >>-- >> Guerry A. Semones BITNET: drogo@tucc.BITNET >> Information Services USENET: gas@ecsvax > >-- > Marc Mengel > > attmail!mmengel > ...!{moss|lll-crg|mtune|ihnp4}!cuuxb!mmengel I am very interested in Marc's report on VP/ix aka Simul-Task 386. I am very familiar with Simul-Task for the AT&T PC 6300 PLUS (no fair comparison possible other than its overall reliability) and casually acquainted with VP/ix for SCO Xenix (still in "controlled release"). I regret to report that I am intimately familiar with Merge/386 from Locus/Microport. Before anyone jumps to the conclusion that this is irrational flaming, stop and think about how frustrated you get when you install a product that breaks your *entire* system, *all* of it. The happiest I have ever been with the Microport product was when the UPS driver carried it away, given to a rather nice fellow who didn't deserve what he thought was a favor. The Microport "product" (I shouldn't dignify it by calling it that) is just not ready for market. It has a number of quirks from which the only recovery is a low level format on the hard disk. I became quite expert at that. Before I proceed I must emphasize I am referring to the _386_ implementation, I'm ignorant of the 286 version. Even more annoying than it's fickle nature and appetite for super blocks is the vendor's cavalier attitude towards the purchaser. It is clearly marked as a beta test version (though the price sheet and advertising is silent about that) but it sells for full retail. There are fixes that have been tested and confirmed but Microport "does not issue replacement beta products for a beta product" (their words, not mine). There are serious flaws in the Merge kernel, both on the UNIX and the DOS sides. Many of the UNIX problems go away by removing the Merge kernel so I have no reason to believe that they are present in the UNIX only kernel (its problems are not pertinent to this discussion). One modest example... If you assign a resource to DOS (COM1 for Crosstalk) it gets correctly relinquished by UNIX but never picked up by DOS. The result is that when you return to UNIX, that device is gone forever (can't be freed by DOS, it was never inherited), reset the machine. The Merge kernel can and does panic rather frequently for various reasons, some of which scribble all over the super block. Since the entire file system is corrupt at that point the recovery is to re-install which means low level format the hard disk. I was told that the format could be bypassed but was never successful in doing so. If the kernel panics during an fsck necessitated by an earlier panic, that seems to be the end of everything. There are some device drivers that will work just fine on a pure UNIX kernel that will seriously aggravate the already fragile nature of the Merge kernel. The lp driver is broken on the UNIX side (they put a line counter in the _driver_, not the filter!) and when you try to print something on the DOS side things get much worse. If you plug and unplug the printer (in this case an HP Laser Jet-II or an Okidata 2350) quickly enough you can get a line out for each unplug-replug sequence. I got so desparate to get something out that I almost got used to that. You get some odd reactions from people who see you doing it... You can cause DOS to sign on to a remote serial terminal. That is exciting and it makes you want more. I have a very simplistic program, written in Aztec C that takes the running time of a TV movie and tells you how many minutes to record on long and short play speed so it fits on a 2 hr tape. I don't know if it was the floating point arithmetic, the fgets, or the printf, but it crashed the emulator and the process' priority downgraded so much and so fast that I could not kill it with -9. The program runs flawlessly under Simul-Task 286 (ironically also a Locus effort) and plain old DOS. Even more curious was that it would run flawlessly on the console. Perhaps if it used something exotic like curses or something it might run on a serial terminal but fgets/printf seem to make it want to crash. I was never able to try a bulky or resource hungry program under Merge/386 because it wouldn't stay up long enough to get any meaningful results. Nor was I able to test any of the nifty disk file gymnastics they provide because I could not keep the file system intact long enough to get around to trying them. The documentation is misleading, incomplete, and repetitive of the marketing hype, woefully lacking in accurate technical content. Aside from the above nit picking, I would not hesitate to recommend the "product" to a competitor I thought might not prosecute me for industrial sabotage. Sorry for the bulk, I wanted my description to be complete enough to convince the reader that I gave it a full court press, not just a quick try and bad rap. I can offer one Simul-Task 386 observation. Microport has virtual consoles in V/386 (and V/AT that I'm using right now). If something goes terribly awry you can ALT-Function key and go to another console to kill/recover. The AT&T 386 UNIX has no such capability so if you should run up a dead end street your reset button (and fsck) will get a lot more exercise. I can not complain that it's needed, I don't have the AT&T product, I'm suggesting that if it is needed, you have a better chance for recovery with virtual consoles. Oddly enough their 286 offering for the 6300 PLUS has a similar capability and the ISC port from which they derived 386 UNIX has them, I'm not sure why they removed them. I'm still curious. Sorry, I need to add a last item. The *same* hardware, no change to anything, runs SCO Xenix 386 and AT&T 386 UNIX flawlessly and ran the Microport 286 product, V/AT flawlessly before I tried V/386. Even if grief is free and you enjoy installing things, for the money, V/386 and particularly Merge/386 (in my non-legal opinion) borders on fraud. -- Bill Kennedy Internet: bill@ssbn.WLK.COM Usenet: { rutgers | cbosgd | ihnp4!petro }!ssbn!bill