[TUHS] Dave Cutler (was Re: Re: Happy birthday, Dick Hustvedt!)

George Michaelson ggm at algebras.org
Wed Feb 21 11:20:19 AEST 2018

I used the VMS PL/1 to write an ISO transport layer as a gigantic
finite state machine in the computed GOTO via a jump table. First job
from graduating. Not my finest moment, but the compiler was awesome.
Fast, rigid. I think I had to get somebody to write some bliss32 or
even ASM to do a trick in the stack for some debug, cool moment for
me. The box of fiches of the OS code was there in the machineroom, It
was a revalation to me you could do that: go "read" the code, and see
what it did.

I don't know if we used VMS C from Dec. I have a feeling if you ran
Eunice, you used pcc or a derivative of pcc. Cross library calling was
pretty straightforward (ok, so passing function addresses and dynamic
structures into FORTRAN not such) and VMS had a well defined 'postbox'
mechanism for async I/O which was wierd if you were used to UNIX but
then .. the entire FS in VMS was wierd if you were used to UNIX.
Wierd, but also comforting: you told the filesystem you wanted fast
record indexing into a file as a binary construct and it said "sure:
I'll do that" and as long as you opened the file with the right
semantics, thats what you got.

I still have my thin-form PL/1 cheetsheet booklet. Its fat. Most of
these were 3-fold cards, its got staples. Not a big language mind you.

So basically, his compiler got me my first paper.

On Wed, Feb 21, 2018 at 2:33 AM, Paul Winalski <paul.winalski at gmail.com> wrote:
> On 2/20/18, Donald ODona <mutiny.mutiny at india.com> wrote:
>> since '86 he was working on an operating system, named Mica, which failed.
>> At 19 Feb 2018 18:13:59 +0000 (+00:00) from Paul Winalski
>> <paul.winalski at gmail.com>:
>>> Dave Cutler was in the VMS group only for VMS version 1.  He rarely
>>> stayed on around for version 2 of anything.  Hustvedt's and Lipman's
>>> contributions for VMS were more extensive and longer-lasting than
>>> Cutler's.
> Cutler had already left the VMS OS group by the time I joined DEC in
> February of 1980.  After VMS he led the team developing PL/I and C
> compilers for VMS.  These shared a common back end called the VAX Code
> Generator (VCG).  The other VMS compilers at the time (Fortran,
> Pascal, Cobol) had their own separate optimizers and code generators.
> The VAX Ada compiler would also use VCG.
> When version 1 of VAX PL/i and VAX C shipped, Cutler worked on
> subsetting the VAX architecture so that a single chip implementation
> could be done, and led the team that produced the MicroVAX I.  The
> MicroVAX architecture emulated expensive instructions such as packed
> decimal.  All of the later, single-chip VAXes used this architecture.
> When the MicroVAX I shipped, Cutler devised a microkernel-based
> real-time operating system for the VAX called VAXeln.
> After VAXeln, Cutler led the team developing a RISC architecture
> follow-on to the VAX called PRISM, and an operating system for it
> called Mica.  Mica had a VAXeln-like microkernel, and the plan was to
> layer personality modules on top of that to implement VMS and
> Unix-style ABIs and system calls.
> Alpha was chosen instead of PRISM as the VAX successor, and that is
> when Cutler left DEC for Microsoft.  Windows NT has a lot of design
> concepts and details previously seen in PRISM and VMS.
> -Paul W.

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