On DEC's TRU64 UNIX it was /mdec
Making a system image with mkisofs I'd follow with
disklabel -rw -f ${UTMP}/${NAME_ISO} /mdec/rzboot.cdfs /mdec/bootrz.cdfs
Cheers,
uncle rubl
--
The more I learn the better I understand I know nothing.
> From: Dave Horsfall
> MAINDEC was certainly on all of their standalone diagnostic media
Actually, it was the name for all their diagnostics (usually stand-alone),
dating back to the paper tape days - when that was the only form they were
distributed in. So it makes sense that it's a short form of 'MAINDEC'.
Noel
I'm curious about the origin of the directory name /usr/mdec.
(I am reminded of it because I've noticed that it lives on in
at least one of the BSDs.)
I had a vague notion that it meant `DEC maintenance' but that
seems a bit clumsy to describe a place holding boot blocks.
A random web board suggests it meant `magnetic DECtape.'
That's certainly not true by the time I came along, when it
contained the master copy of the disk boot block(s).
But I suppose it could have meant that early on and
the name just carried forward.
A quick skim of the V1-V7 manuals doesn't explain the name.
Anyone have any clearer memories than I do? Doug or Ken or
anyone who was there when it was coined, do you still recall?
Norman Wilson
Toronto ON
> Date: Sat, 12 Nov 2022 17:56:24 -0800
> From: Larry McVoy <lm(a)mcvoy.com>
> Subject: [TUHS] Re: DG UNIX History
>
> It sounds like they could have supported mmap() easily. I'd love to see
> this kernel, it sounds to me like it was SunOS with nicely done SMP
> support. The guy that said he'd never seen anything like it before or
> since, just makes me want to see it more.
> I know someone who was friends with one of the kernel guys, haven't talked
> to her in years but I'll see if I can find anything.
Following on from the exchange on TUHS about DG-UX, it would seem to me that the (Unix) unified cache was invented at least three times for Unix:
- John Reiser at AT&T
- At Sun
- At DG
As to the latter I could find two leads that might help you finding out more. It would seem that this unique Unix is specifically DG-UX version 4:
https://web.archive.org/web/20070930212358/http://www.accessmylibrary.com/c…
and
Michael H. Kelly and Andrew R. Huber, "Engineering a (Multiprocessor) Unix Kernel", Proceedings of the Autumn 1989 EUUG Conference, European Unix Systems User Group, Vienna, Austria, 1989, pp. 7- 19.
The unified cache isn’t mentioned, but it would seem that the multiprocessor redesign might have included it. Maybe the author names are helpful. I could not find the paper online, but there was a web page suggesting that a paper copy still exists in a (university?) library in Sweden.
=====
Publication: DG Review
Publication Date: 01-NOV-88
Author: Huber, Andrew R.
DG-UX 4.00: DG's redesigned kernel lays the foundation for future UNIX systems. (includes related article on DG-UX 4.00's file system and an excerpt from Judith S. Hurwitz's 'Data General's UNIX strategy: an evaluation' report)
COPYRIGHT 1988 New Media Publications
DG/UX 4.00
Revision 4.00 of Data General's native UNIX operating system siginificantly enhances the product and adds unique capabilities not found in other UNIX implementations. This article reviews the goals of DG/UX 4.00 and discusses some of its features.
When DG released DG/UX 1.00 in March, 1985, it was based on AT&T's System V Release 2 and incorporated the Berkeley UNIX file system and networking.
As DG/UX grew, it continued to incorporate functions of the major standard UNIX systems, as illustrated in the following timeline:
* DG/UX 1.00 March, 1985 Based on System V Release 2 and Berkely 4.1.
Included Berkely 4.2 file system and TCP/IP (LAN).
* DG/UX 2.00, September, 1985 Added Berkeley 4.2 system calls.
* DG/UX 3.00, April 1986 Added support for new DG hardware.
* DG/UX 3.10 March, 1987 Added Sun Microsystem's Network File System.sup.(R) Added X Windows.
* DG/UX 4.00, August, 1988 Re-designed and re-implemented kernel and file system.
I spotted this when glancing through a book catalogue; well, with a title
like that how could I miss it?
Subtitled "How 26 Lines of Code Changed the World", edited by Torie Bosch
and illustrated by Kelly Chudler (can't say that I've heard of them).
Summary:
``Programming is behind so much of life today, and this book draws together
a group of distinguished thinkers and technologists to reveal the
stories and people behind the computer coding that shapes our
world. From how university's [sic] databases were set up to
recognise only two genders to the first computer worm and the
first pop-up ad, the diverse topics reveal the consequences of
historical decisions and their long-lasting, profound implications.
Pb $34.99''
Lines of code, eh? :-)
Abbey's Bookshop: www.abbeys.com.au
Disclaimer: I have no connection with them, but I'll likely buy it.
-- Dave
Clem Cole:
Yep -- but not surprising. There were a bunch of folks at DG that had
worked on a single-level store system (Project Fountain-Head) that had
failed [some of that story is described in Kidder's book].
====
Are you sure? I thought Fountainhead was a Rand project.
Norman Wilson
Toronto ON
PS: if you don't get it, consider yourself fortunate.
>> To be honest, I've forgotten many (most) of the details. But that sounds
>> about right. As I remember it, it was like SunOS. The key point was that
>> the kernel only had one view of the memory system period, no FS
>> buffer cache etc...which was a departure from many of the traditional UNIX
>> implementations. IIRC they did not support BSD's mmap -- but check the
> It sounds like they could have supported mmap() easily. I'd love to see
> this kernel, it sounds to me like it was SunOS with nicely done SMP
> support. The guy that said he'd never seen anything like it before or
> since, just makes me want to see it more.
"One view of the memory, period." That describes Multics.
Doug
This is what Scott Lee, who ran the Eclipse at Georgia Tech
recalls. He has given permission for me to forward it, with
the caveat that it was long ago and that "memories are malleable".
Arnold
> Date: Mon, 14 Nov 2022 05:35:51 -0500
> Subject: Re: [TUHS] DG UNIX History
> From: scott(a)thelees.org
> To: arnold(a)skeeve.com
>
> > I'm pretty sure that DG never ported DG-UX to the Nova. There was
> > a native port to the Eclipse (32 bit). There was also a Eunice-style
> > Unix environment that sat on top of their native OS, whatever it was
> > called.
>
> Yeh, that was an MV-10000 that we received. As I remember it, we also got
> a copy of DG-UX, which was a port of SYS Vr2, not r3 as mentioned. I
> think that it may have also had a directory with UCB versions of a bunch
> of the utilities ported over so you could run either SysV tools or UCB
> tools.
>
> LeBlanc was going to use it to teach ADA, so I was building some tools to
> create/maintain user accounts, but I believe that I left just before they
> were actually getting around to that.
>
> I was also playing with it on the side, when no one else was using it, to
> build a small OS on it. I found that it followed a lot of the Nova
> behavior, so I figured out how to write code onto a tape and bootstrap it
> into the machine. Wrote a tape driver and a console driver and was
> working on a disk driver. Targeting putting a small OS on it.
>
> Wow... I had almost forgotten that it even existed until I saw this.
>
> Enjoy,
> Scott
