[TUHS] Unix clones

Wesley Parish wes.parish at paradise.net.nz
Fri Apr 7 11:12:21 AEST 2017


's/DNS/DNA/' - Not a problem. Thanks!

I'd come across Thoth mentioned in an OS book at the U of Canterbury (NZ) Science Library; they also 
had a copy of the Tunis book. But I never took the time to read them.

Getting them put into a time frame is useful - it gives an external perspective to Salus' book, eg, this is 
what some non-Unix folk thought of Unix at the time.

Wesley Parish

Quoting Clem Cole <clemc at ccc.com>:

> s/DNS/DNA/ - dyslexia sucks....
> 
> On Thu, Apr 6, 2017 at 2:02 PM, Clem Cole <clemc at ccc.com> wrote:
> 
> > ​try-II sorry about that...​
> >
> >
> > On Wed, Apr 5, 2017 at 9:18 PM, Wesley Parish
> <wes.parish at paradise.net.nz>
> > wrote:
> >
> >> The mention of UNOS a realtime "clone" of Unix in a recent thread
> raises
> >> a question for me. How many
> >> Unix clones are there?
> >>
> >
> > ​An interesting question.... I'll take a shot at this in a second,
> note
> > there is a Wikipedia page:
> https://en.wikipedia.org/wiki/Category:Unix_
> > variants that I don't fully agree with.
> >
> > The problem with all of this question is really depends where you
> place
> > which boundary on the following continuum:
> >
> > non-unix add-unix ideas trying to be
> > unix might as well be unix research unix
> > stream
> >
> > eg VMS eg Domain eg UNOS
> > eg Sys V, BSD/386 & Linux Vx & BSD VAX
> >
> >
> > Different people value different things. So here is my take from the
> > "cloned" systems I used/was basically aware....
> >
> > Idris was a V6 clone for the PDP-11, which I saw 1978ish. I can say I
> > was able to recompile code from v6 and it "just worked" so from a
> user's
> > standpoint it might as well has been. But the compilers and
> assemblers
> > were different and I never tried anything "hard"
> >
> > The first attempt to "clone" v7 that I knew about was in France, and
> > written in Pascal - I think at Ecole Tech in Paris? The name of the
> > project escapes me, but they presented the work in the 1979/80 winter
> > USENIX (Blackhole) conference in Denver. There were no proceedings in
> > those days. I believe it also ran on the PDP-11, but I never ran it
> so; so
> > I have no idea how easy it was to move things from Seventh Edition.
> But I
> > also don't think they were working binary compatibility, so I think
> it
> > landed more toward the center.
> >
> > The Cruds folks (Goldberg) wrote UNOS shortly there after (early 80s)
> > It was definitely not UNIX although it tried to have be mostly. We
> had
> > CRDS box at Masscomp and before I arrived they plan had been to use it
> get
> > code working before the RTU was running. But the truth was it failed
> > because it was not UNIX. The 68000 vs Vax issues were far, far less of
> an
> > issue than UNOS != UNIX. To Goldberg's credit, he did have a couple
> of
> > cool things in it. I believe only system commercial systems that used
> > Kanodia & Reed's Sequences and Eventcounts, were UNOS, Apollo Doman,
> and
> > Stellar's Stellix (I'm not sure about DG - they might have also at
> one
> > point). But these were hidden in the kernel. Also the driver model he
> > had was different, so there was no gain writing drivers there.
> >
> > Mike Malcom & Dave Cheriton at Waterloo developed Thoth (Thoth -
> Thucks),
> > which was written in B, IIRC. Ran on the PDP-11 and was very fast and
> > light. It was the first "ukernel" UNIX-like/clone system.. Moving
> code
> > from V7 was pretty simple and there was attempt to make it good enough
> to
> > make it easy to move things, but it was not trying to be UNIX so it
> was
> > somewhere in the middle.
> >
> > The Tunis folks seem to have been next. This was more in the left
> side
> > of the page than the right. I think they did make run on the PDP-11,
> but
> > I'm not so sure how easy it was to move code. If you used their
> > concurrent Pascal, I suspect that code moved. But I'm not sure how
> easy it
> > was to move a raw K&R "White Book" C code.
> >
> > CMU's Accent (which was redo of Rochester's RIG) came around the same
> > time. Like Tunis the system language was an extended Pascal and in
> fact
> > the target was the triple drip Perq (aka the Pascalto). The C
> compiler
> > for it was late, and moving code was difficult, the UNIX influence
> was
> > clear.
> >
> > Apollo's Aegis/Domain really came next - about 82/83 ish. Like Accent
> it
> > was written in hacked up Pascal and the command were in
> Ratfor/Fortran
> > (from the SW Tool User's Group). C showed up reasonably early, but
> the
> > focus did not start trying to be UNIX. In fact, they were very
> > successfully and were getting ISV's to abandon VMS for them at a very
> good
> > clip. UNIX clearly influenced the system, but it was not trying to be
> > UNIX, although moving code from BSD or V7 could be done fairly
> easily.
> >
> > Tannebaum then did MINIX. Other than 8086 vs PDP-11-ism, it was a
> pretty
> > darned good clone. You could recompile and most things pretty much
> "just
> > worked." He did not support ptrace and few other calls, but as a basic
> V7
> > system running on a pure PDP PC, it was remarkably clean. It also had
> a
> > large number of languages and it was a great teaching system - which
> is
> > what Andy created it be. A problem was that UNIX had moved on by the
> > time Andy released it. So BSD & V8 were now pretty much the definition
> of
> > "UNIX" - large address spaces were needed. As were the BSD tools
> > extensions, such as vi, csh. Also UUCP was now very much in the
> thing,
> > and while it was a pure v7 clone, it was the lack of "tools" that made
> it
> > not a good system to "use" and it's deficiencies out weighed the
> value.
> > Plus as discussed elsewhere, BSD/386 would appear.
> >
> > Steve Ward's crew at MIT created TRIX, which was a UNIX-like,
> although
> > instead of everything being a file, everything was a process. This
> was
> > supposed to be the system that rms was originally going to use for
> GNU, but
> > I never knew what happened. Noel might. I thought it was a cool
> system,
> > although it was a mono-kernel and around this time, most of the OS
> research
> > had gone ukernel happy.
> >
> > Coherent was announcement and its provenance is questioned, although
> as
> > discussed was eventually released from the AT&T official inquiry and
> you
> > can look it your self. It was clearly a V7 clone for the PC and was
> more
> > complete than Minix. I also think they supported the 386 fairly
> quickly,
> > which may have made it more interesting from a commercial standpoint.
> It
> > also had more of the BSD tools available than Minix did when it was
> first
> > released.
> >
> > CMU rewrites Accent to create Mach, but this time splices the BSD
> kernel
> > inside of it so that the 4.1BSD binaries "just work." So it's bit
> UNIX
> > and a new system all in one. So which is it? This system would begat
> > OSF/1 and eventually become Apple's Mac OS? I think its UNIX, but one
> can
> > claim its not either....
> >
> > By this point in time the explosion occurs. You have Lion's book,
> Andy's
> > and Maury Bach's book on the street. he genie is clearly out of the
> bottle,
> > and there is a ton of code out there and the DNS is getting all mixed
> up.
> > Doug Comer does Xinu, Sheraton does V-kernel, Thoth is rewritten to
> become
> > QNX, and a host of others I have not repeated. BSD's CSRG group would
> > break up, BSDi would be created and their 386 code come out. It was
> > clearly "might as well be" if it was not. Soon, Linus would start
> with
> > Minix and the rest is history on the generic line.
> >
> > Clem
> >
> >
>  



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