[TUHS] Happy birthday, core dumped

[TUHS] Happy birthday, core dumped

[Doug McIlroy]

> It's always been a bit of a mystery to me why Thompson and Ritchie decided they needed to write a new executive - UNICS - rather than use DECsys.

It was the other way around. They had conceived a clean, simple, yet
powerful, operating system and needed a machine to build it on. A
cast-off PDP-7 happened to be at hand.

Doug

[TUHS] Happy birthday, core dumped

[iking]

Interesting - what's your source?  It was also my understanding they used the -7 'because it was there' but that they had pitched for a PDP-10, which had TOPS-10.  - Ian 

Sent from my android device.

-----Original Message-----
From: Doug McIlroy <doug@cs.dartmouth.edu>
To: tuhs at minnie.tuhs.org
Sent: Wed, 18 Jun 2014 4:06 AM
Subject: Re: [TUHS] Happy birthday, core dumped

> It's always been a bit of a mystery to me why Thompson and Ritchie decided they needed to write a new executive - UNICS - rather than use DECsys.

It was the other way around. They had conceived a clean, simple, yet
powerful, operating system and needed a machine to build it on. A
cast-off PDP-7 happened to be at hand.

Doug
_______________________________________________
TUHS mailing list
TUHS at minnie.tuhs.org
https://minnie.tuhs.org/mailman/listinfo/tuhs
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[TUHS] Happy birthday, core dumped

[Dan Cross]

On Wed, Jun 18, 2014 at 10:43 AM, <iking at killthewabbit.org> wrote:

> Interesting - what's your source?  It was also my understanding they used
> the -7 'because it was there' but that they had pitched for a PDP-10, which
> had TOPS-10.  - Ian
>

*laugh*

Doug, weren't you department head at the time, or did that come later?

        - Dan C.


> Sent from my android device.
>
> -----Original Message-----
> From: Doug McIlroy <doug at cs.dartmouth.edu>
> To: tuhs at minnie.tuhs.org
> Sent: Wed, 18 Jun 2014 4:06 AM
> Subject: Re: [TUHS] Happy birthday, core dumped
>
> > It's always been a bit of a mystery to me why Thompson and Ritchie
> decided they needed to write a new executive - UNICS - rather than use
> DECsys.
>
> It was the other way around. They had conceived a clean, simple, yet
> powerful, operating system and needed a machine to build it on. A
> cast-off PDP-7 happened to be at hand.
>
> Doug
> _______________________________________________
> TUHS mailing list
> TUHS at minnie.tuhs.org
> https://minnie.tuhs.org/mailman/listinfo/tuhs
>
> _______________________________________________
> TUHS mailing list
> TUHS at minnie.tuhs.org
> https://minnie.tuhs.org/mailman/listinfo/tuhs
>
>
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[TUHS] Happy birthday, core dumped

[A. P. Garcia]

On Wed, Jun 18, 2014 at 9:43 AM,  <iking at killthewabbit.org> wrote:
> Interesting - what's your source?

:-)
that's like asking george martin for his source regarding a beatles song...

[TUHS] Happy birthday, core dumped

[Douglas Comer]

> Ahh!  I wonder if they'll be making images and PDFs available?

If you want to check, my contact has been:

	 William Harnack <wharnack at computerhistory.org>

Doug

[TUHS] Happy birthday, core dumped

[Doug McIlroy]

They pitched a PDP-10 for a similar reason--hardware to build a
bigger Unix on. When a small pot of end-of-year money appeared,
they took a PDP-11 instead--serendipitously, because university
folks started proving this elegant system on cheap hardware
in many projects in small labs, which they never could have
done had the system existed on a PDP-10 mainframe. While
upper management did not directly cause Unix to be built,
their decisions to abandon Multics and not to buy a PDP-10
were notable causes for its creation and spread.

Doug


> Date: Wed, 18 Jun 2014 07:43:51 -0700
> From: iking at killthewabbit.org
> To: tuhs at minnie.tuhs.org,Doug McIlroy <doug at cs.dartmouth.edu>
> Subject: Re: [TUHS] Happy birthday, core dumped
> Message-ID: <ef723f8a-52b6-4810-be59-1837c75b1da3.maildroid at localhost>
> Content-Type: text/plain; charset="utf-8"
> 
> Interesting - what's your source?  It was also my understanding they used the -7 'because it was there' but that they had pitched for a PDP-10, which had TOPS-10.  - Ian
> 
> Sent from my android device.
> 
> -----Original Message-----
> From: Doug McIlroy <doug at cs.dartmouth.edu>
> To: tuhs at minnie.tuhs.org
> Sent: Wed, 18 Jun 2014 4:06 AM
> Subject: Re: [TUHS] Happy birthday, core dumped
> 
> 
> > It's always been a bit of a mystery to me why Thompson and Ritchie decided they needed to write a new executive - UNICS - rather than use DECsys.
> 
> It was the other way around. They had conceived a clean, simple, yet
> powerful, operating system and needed a machine to build it on. A
> cast-off PDP-7 happened to be at hand.
> 
> Doug

[TUHS] Happy birthday, core dumped

[Noel Chiappa]

    > From: "A. P. Garcia" <a.phillip.garcia at gmail.com>

    > that's like asking george martin for his source regarding a beatles
    > song...

Reminds me of the person on Wikipedia who tried to argue with me about the
'History of the Internet' article... :-)


    > From: John Cowan <cowan at mercury.ccil.org>

    >> scj at yaccman.com scripsit:

    >> a Dec repair person who ran "preventive maintenance" on our disc that
    >> wiped out the file system! His excuse was that Dec didn't support
    >> "permanent storage" on the disc at the time...

    > Next time, mount a scratch monkey.

It was probably a fixed-head disk (RS11 or RS04); can't exactly stick a
different pack in! :-) Probably the DEC OS's only used it for swapping or
something, since they were both relatively small - 512KB.

(Speaking of RS11's: the first PDP-11 I used - an 11/20 running RSTS - had a
grand total disk storage of _one_ RS11!)


And speaking of putting file systems on them: I recently wrote this command
for V6 called 'si' which allowed me (among many other interesting things) to
watch the contents of the disk buffer(s). It turns out that even with other
packs mounted, the buffer is almost always completely full of blocks from the
root device; it makes plain the value of having the root on a _really_
fast disk. 

I don't know if that usage pattern is because /bin is there, or because pipes
get created on the root, or what. When I get up the energy I'll move /bin to
another drive (yeah, yeah, I know - good way to lose and create a systen that
won't boot, so I'll actually make a _copy_ of /bin and mount it _over_ the
original /bin - probably a host of interesting errors there, e.g. if a process
has the old /bin as its current dir), and see what the cache contents look
like then.

	Noel

[TUHS] Happy birthday, core dumped

[John Cowan]

Noel Chiappa scripsit:

> Reminds me of the person on Wikipedia who tried to argue with me about the
> 'History of the Internet' article... :-)

To be fair, Wikipedia is supposed to be based on secondary sources.  Your
memories are a nullary source.

-- 
John Cowan          http://www.ccil.org/~cowan        cowan at ccil.org
BALIN FUNDINUL          UZBAD KHAZADDUMU
BALIN SON OF FUNDIN     LORD OF KHAZAD-DUM

[TUHS] Happy birthday, core dumped

[Douglas Comer]

  > > Have Xinu media to go with it? It's something I've been trying to track down. ;)
  > 
  > Have you asked Doug?  I've copied him

I just donated my extra copy of Xinu tapes and floppies to the computer museum
(along with first editions of the books).

  > (Hey Doug, you should be on this list, all the long time unix nerds seem to be
  > here, lots of fun with memory lane).

I'd be happy to join.

Doug

[TUHS] Happy birthday, core dumped

[Cory Smelosky]

On Wed, 18 Jun 2014, Douglas Comer wrote:

>  > > Have Xinu media to go with it? It's something I've been trying to track down. ;)
>  >
>  > Have you asked Doug?  I've copied him
>
> I just donated my extra copy of Xinu tapes and floppies to the computer museum
> (along with first editions of the books).
>

Ahh!  I wonder if they'll be making images and PDFs available?

>  > (Hey Doug, you should be on this list, all the long time unix nerds seem to be
>  > here, lots of fun with memory lane).
>
> I'd be happy to join.
>

It seems like a place that'll help with my crazy projects, too.

> Doug
>
>

-- 
Cory Smelosky
http://gewt.net Personal stuff
http://gimme-sympathy.org Projects

[TUHS] Happy birthday, core dumped

[Norman Wilson]

  Interesting - what's your source?  It was also my understanding they
  used the -7 'because it was there' but that they had pitched for a
  PDP-10, which had TOPS-10.

======

I think Doug's source is in the class `personal observation.'
He was there at the time; Ken and Dennis's department head, if
I've got it right.

Remember that Bell Labs had just disengaged itself from the
Multics project.  The interest in a new OS sprang partly
from the desire to have a comfortable multi-user system
now that Multics was no longer available.  That's why the
DEC operating systems of the time, which were (as I understand
it) simple single-user monitors, didn't fill the bill.

The character of the players matters too: remember that
Ken is the guy who one night sat down to write a Fortran
compiler because real systems have Fortran, and ended up
inventing B instead.

I've read that there was indeed a pitch to buy a PDP-10; that
there was some complicated plan to lower the effective cost;
and that upper management (not Doug) turned it down because
`Bell Labs doesn't do business that way.'  I think I got that
from Dennis's retrospective paper, published in the 1984
all-UNIX issue of the Bell Labs Techical Journal, a must-read
(along with the late-1970s all-UNIX issue of BSTJ) for anyone
on this list.

[TUHS] Happy birthday, core dumped

[Larry McVoy]

On Wed, Jun 18, 2014 at 11:03:56AM -0400, Norman Wilson wrote:
> I think I got that
> from Dennis's retrospective paper, published in the 1984
> all-UNIX issue of the Bell Labs Techical Journal, a must-read
> (along with the late-1970s all-UNIX issue of BSTJ) for anyone
> on this list.

Indeed.  I just packed up my office, all the books, and the BSTJ were the
only things I kept close.  Well, that and the Xinu books, I've got a soft
spot for those.
-- 
---
Larry McVoy            	     lm at mcvoy.com             http://www.mcvoy.com/lm 

[TUHS] Happy birthday, core dumped

[Cory Smelosky]

Sent from my advertising assimilation device

> On 18 Jun 2014, at 10:00, Larry McVoy <lm at mcvoy.com> wrote:
> 
>> On Wed, Jun 18, 2014 at 11:03:56AM -0400, Norman Wilson wrote:
>> I think I got that
>> from Dennis's retrospective paper, published in the 1984
>> all-UNIX issue of the Bell Labs Techical Journal, a must-read
>> (along with the late-1970s all-UNIX issue of BSTJ) for anyone
>> on this list.
> 
> Indeed.  I just packed up my office, all the books, and the BSTJ were the
> only things I kept close.  Well, that and the Xinu books, I've got a soft
> spot for those.

Have Xinu media to go with it? It's something I've been trying to track down. ;)


> -- 
> ---
> Larry McVoy                     lm at mcvoy.com             http://www.mcvoy.com/lm 
> _______________________________________________
> TUHS mailing list
> TUHS at minnie.tuhs.org
> https://minnie.tuhs.org/mailman/listinfo/tuhs

[TUHS] Happy birthday, core dumped

[Larry McVoy]

On Wed, Jun 18, 2014 at 12:58:45PM -0400, Cory Smelosky wrote:
> 
> 
> Sent from my advertising assimilation device
> 
> > On 18 Jun 2014, at 10:00, Larry McVoy <lm at mcvoy.com> wrote:
> > 
> >> On Wed, Jun 18, 2014 at 11:03:56AM -0400, Norman Wilson wrote:
> >> I think I got that
> >> from Dennis's retrospective paper, published in the 1984
> >> all-UNIX issue of the Bell Labs Techical Journal, a must-read
> >> (along with the late-1970s all-UNIX issue of BSTJ) for anyone
> >> on this list.
> > 
> > Indeed.  I just packed up my office, all the books, and the BSTJ were the
> > only things I kept close.  Well, that and the Xinu books, I've got a soft
> > spot for those.
> 
> Have Xinu media to go with it? It's something I've been trying to track down. ;)

Have you asked Doug?  I've copied him (Hey Doug, you should be on this list,
all the long time unix nerds seem to be here, lots of fun with memory lane).

Cheers,

--lm

[TUHS] Happy birthday, core dumped

[Dan Cross]

The paper with that quote is still linked from dmr's page:
http://cm.bell-labs.com/who/dmr/hist.html



On Wed, Jun 18, 2014 at 11:03 AM, Norman Wilson <norman at oclsc.org> wrote:

>   Interesting - what's your source?  It was also my understanding they
>   used the -7 'because it was there' but that they had pitched for a
>   PDP-10, which had TOPS-10.
>
> ======
>
> I think Doug's source is in the class `personal observation.'
> He was there at the time; Ken and Dennis's department head, if
> I've got it right.
>
> Remember that Bell Labs had just disengaged itself from the
> Multics project.  The interest in a new OS sprang partly
> from the desire to have a comfortable multi-user system
> now that Multics was no longer available.  That's why the
> DEC operating systems of the time, which were (as I understand
> it) simple single-user monitors, didn't fill the bill.
>
> The character of the players matters too: remember that
> Ken is the guy who one night sat down to write a Fortran
> compiler because real systems have Fortran, and ended up
> inventing B instead.
>
> I've read that there was indeed a pitch to buy a PDP-10; that
> there was some complicated plan to lower the effective cost;
> and that upper management (not Doug) turned it down because
> `Bell Labs doesn't do business that way.'  I think I got that
> from Dennis's retrospective paper, published in the 1984
> all-UNIX issue of the Bell Labs Techical Journal, a must-read
> (along with the late-1970s all-UNIX issue of BSTJ) for anyone
> on this list.
> _______________________________________________
> TUHS mailing list
> TUHS at minnie.tuhs.org
> https://minnie.tuhs.org/mailman/listinfo/tuhs
>
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[TUHS] Happy birthday, core dumped

[scj]

Bell Labs' decision to pull out of Multics still ranks in my mind as one
of the best management decisions I've ever had close contact with...

With respect to Dec's OSs vs Unix, I remember a visit from a Dec repair
person who ran "preventive maintenance" on our disc that wiped out the
file system!  His excuse was that Dec didn't support "permanent storage"
on the disc at the time...

[TUHS] Happy birthday, core dumped

[John Cowan]

scj at yaccman.com scripsit:

> With respect to Dec's OSs vs Unix, I remember a visit from a Dec repair
> person who ran "preventive maintenance" on our disc that wiped out the
> file system!  His excuse was that Dec didn't support "permanent storage"
> on the disc at the time...

Next time, mount a scratch monkey.

-- 
John Cowan          http://www.ccil.org/~cowan        cowan at ccil.org
The penguin geeks is happy / As under the waves they lark
The closed-source geeks ain't happy / They sad cause they in the dark
But geeks in the dark is lucky / They in for a worser treat
One day when the Borg go belly-up / Guess who wind up on the street.

[TUHS] Happy birthday, core dumped

[Norman Wilson]

Jay Forrester, who invented core memory, first described it in
a lab notebook 65 years ago today.

(Thanks to the Living Computer Museum, through whose Twitter
feed I learned this tidbit.  It's a place--the real museum,
not just the Twitter feed--many on this list might enjoy:
among their aged-but-working computers are a Xerox Star and
a PDP-7.)

Norman Wilson
Toronto ON

[TUHS] Happy birthday, core dumped

[iking]

Small correction: not a Star, an Alto.  :-)  

Sent from my android device.

-----Original Message-----
From: Norman Wilson <norman@oclsc.org>
To: tuhs at minnie.tuhs.org
Sent: Sun, 15 Jun 2014 11:19 AM
Subject: [TUHS] Happy birthday, core dumped

Jay Forrester, who invented core memory, first described it in
a lab notebook 65 years ago today.

(Thanks to the Living Computer Museum, through whose Twitter
feed I learned this tidbit.  It's a place--the real museum,
not just the Twitter feed--many on this list might enjoy:
among their aged-but-working computers are a Xerox Star and
a PDP-7.)

Norman Wilson
Toronto ON
_______________________________________________
TUHS mailing list
TUHS at minnie.tuhs.org
https://minnie.tuhs.org/mailman/listinfo/tuhs
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[TUHS] Happy birthday, core dumped

[Gregg Levine]

Hello!
Interesting.
I know I've seen the Star system rig before. But the Xerox Alto one is
new to me. Wasn't the PDP-7 the fellow where UNIX really got its start
on before they moved it to a PDP-11?
-----
Gregg C Levine gregg.drwho8 at gmail.com
"This signature fought the Time Wars, time and again."


On Mon, Jun 16, 2014 at 12:13 PM,  <iking at killthewabbit.org> wrote:
> Small correction: not a Star, an Alto.  :-)
>
> Sent from my android device.
>
>
> -----Original Message-----
> From: Norman Wilson <norman at oclsc.org>
> To: tuhs at minnie.tuhs.org
> Sent: Sun, 15 Jun 2014 11:19 AM
> Subject: [TUHS] Happy birthday, core dumped
>
> Jay Forrester, who invented core memory, first described it in
> a lab notebook 65 years ago today.
>
> (Thanks to the Living Computer Museum, through whose Twitter
> feed I learned this tidbit.  It's a place--the real museum,
> not just the Twitter feed--many on this list might enjoy:
> among their aged-but-working computers are a Xerox Star and
> a PDP-7.)
>
> Norman Wilson
> Toronto ON
> _______________________________________________
> TUHS mailing list
> TUHS at minnie.tuhs.org
> https://minnie.tuhs.org/mailman/listinfo/tuhs
>
> _______________________________________________
> TUHS mailing list
> TUHS at minnie.tuhs.org
> https://minnie.tuhs.org/mailman/listinfo/tuhs
>

[TUHS] Happy birthday, core dumped

[John Cowan]

Gregg Levine scripsit:

> I know I've seen the Star system rig before. But the Xerox Alto one is
> new to me. Wasn't the PDP-7 the fellow where UNIX really got its start
> on before they moved it to a PDP-11?

It was.  The 18-bit systems were the red-headed stepchild of the DEC world.
The PDP-1, PDP-4, and PDP-7 systems had no DEC-supplied operating system,
and the PDP-9 only a minimal one, about like OS/8.  Not until the terminal
18-bit system, the PDP-15, were PDP-11 class operating systems provided.
Consequently, the Bell Labs PDP-7 was essentially useless.

-- 
John Cowan          http://www.ccil.org/~cowan        cowan at ccil.org
Awk!" sed Grep. "A fscking python is perloining my Ruby; let me bash
    him with a Cshell!  Vi didn't I mount it on a troff?" --Francis Turner

[TUHS] Happy birthday, core dumped

[Greg 'groggy' Lehey]

On Monday, 16 June 2014 at 21:38:40 -0400, John Cowan wrote:
> Gregg Levine scripsit:
>
>> I know I've seen the Star system rig before. But the Xerox Alto one is
>> new to me. Wasn't the PDP-7 the fellow where UNIX really got its start
>> on before they moved it to a PDP-11?
>
> It was.  The 18-bit systems were the red-headed stepchild of the DEC world.
> The PDP-1, PDP-4, and PDP-7 systems had no DEC-supplied operating system,
> and the PDP-9 only a minimal one, about like OS/8.  Not until the terminal
> 18-bit system, the PDP-15, were PDP-11 class operating systems provided.
> Consequently, the Bell Labs PDP-7 was essentially useless.

Sounds like it was crying out for somebody to write an operating
system for it :-)

Greg
--
Sent from my desktop computer.
Finger grog at FreeBSD.org for PGP public key.
See complete headers for address and phone numbers.
This message is digitally signed.  If your Microsoft MUA reports
problems, please read http://tinyurl.com/broken-mua
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[TUHS] Happy birthday, core dumped

[iking]

Well, the University of Oregon might disagree with you about the PDP-7.  They ran the DECsys monitor, which ISTR  was the first such software product from DEC outside the 36-bit line (the PDP-6 and -7 were introduced in the same year).  U of O took delivery of their -7 in 1966 and it saw active service for at least three decades, with over thirty doctorates earned based on research performed on the system.  Hardly useless....  

It's always been a bit of a mystery to me why Thompson and Ritchie decided they needed to write a new executive - UNICS - rather than use DECsys.  True, DECsys isn't anything to shout about and Unix is clearly more useful - but IMHO Spacewar! could have been coded in the DECsys 'environment'.  I infer that they saw broader utility and application in a more capable executive - which obviously turned out to be true!  

The U of O PDP-7 is the one currently residing at the Living Computer Museum (I used to maintain it).  

And what's wrong with OS/8?  Minimal, yes - what do you want, Windows Vista?  :-)   - Ian 

Sent from my android device.

-----Original Message-----
From: John Cowan <cowan@mercury.ccil.org>
To: Gregg Levine <gregg.drwho8 at gmail.com>
Cc: tuhs at minnie.tuhs.org
Sent: Mon, 16 Jun 2014 6:38 PM
Subject: Re: [TUHS] Happy birthday, core dumped

Gregg Levine scripsit:

> I know I've seen the Star system rig before. But the Xerox Alto one is
> new to me. Wasn't the PDP-7 the fellow where UNIX really got its start
> on before they moved it to a PDP-11?

It was.  The 18-bit systems were the red-headed stepchild of the DEC world.
The PDP-1, PDP-4, and PDP-7 systems had no DEC-supplied operating system,
and the PDP-9 only a minimal one, about like OS/8.  Not until the terminal
18-bit system, the PDP-15, were PDP-11 class operating systems provided.
Consequently, the Bell Labs PDP-7 was essentially useless.

-- 
John Cowan          http://www.ccil.org/~cowan        cowan at ccil.org
Awk!" sed Grep. "A fscking python is perloining my Ruby; let me bash
    him with a Cshell!  Vi didn't I mount it on a troff?" --Francis Turner
_______________________________________________
TUHS mailing list
TUHS at minnie.tuhs.org
https://minnie.tuhs.org/mailman/listinfo/tuhs
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[TUHS] Happy birthday, core dumped

[John Cowan]

iking at killthewabbit.org scripsit:

> Well, the University of Oregon might disagree with you about the PDP-7.
> They ran the DECsys monitor, 

Ah, I didn't know about that.  Still, pretty sub-minimal:  Fortran II,
assembler, editor, period.  It made OS/8 look quite rich by comparison.

> Hardly useless....

However, according to the manual, DECsys required an 8Kword PDP-7, whereas
the "Space Travel" (not "Spacewar!") machine had only 4Kwords.

> And what's wrong with OS/8?  

Nothing.  Indeed, I cut my teeth on it on a PDP-8/M with 8K and a single
DECtape with the driver in ROM.  I was using the term descriptively to
indicate the kind of OS available for the PDP-9.  A modified version also
ran on the '15, it seems.  But the native OSes were DOS-15 (roughly RT-11)
and RSX-15 (a classic DEC RSX).

-- 
John Cowan          http://www.ccil.org/~cowan        cowan at ccil.org
        "Not to know The Smiths is not to know K.X.U."  --K.X.U.

[TUHS] Happy birthday, core dumped

[Ian King]

On Jun 17, 2014, at 5:14 AM, John Cowan wrote:

> iking at killthewabbit.org scripsit:
>
>> Well, the University of Oregon might disagree with you about the  
>> PDP-7.
>> They ran the DECsys monitor,
>
> Ah, I didn't know about that.  Still, pretty sub-minimal:  Fortran II,
> assembler, editor, period.  It made OS/8 look quite rich by  
> comparison.

U of O also had FOCAL running on it, which may have been a local port  
- I'll have to find out.
>
>> Hardly useless....
>
> However, according to the manual, DECsys required an 8Kword PDP-7,  
> whereas
> the "Space Travel" (not "Spacewar!") machine had only 4Kwords.

Yes, thanks for the correction - a slip of the virtual tongue.  I  
didn't realize the Bell Labs machine was so basic - in fact, it was  
my understanding that the basic machine was 8Kwords.  The machine at  
LCM actually has 16K, with a DEC field mod to allow it to be  
addressed in PDP-9/15 fashion.

>> And what's wrong with OS/8?
>
> Nothing.  Indeed, I cut my teeth on it on a PDP-8/M with 8K and a  
> single
> DECtape with the driver in ROM.  I was using the term descriptively to
> indicate the kind of OS available for the PDP-9.  A modified  
> version also
> ran on the '15, it seems.  But the native OSes were DOS-15 (roughly  
> RT-11)
> and RSX-15 (a classic DEC RSX).

OK, we're good then.  :-)  I have a soft spot for the 12-bit  
machines, if it doesn't show.  -- Ian