[TUHS] Dave Cutler recollection about Xenix

[TUHS] Dave Cutler recollection about Xenix

[Skip Tavakkolian]

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This might be interesting to some. It is a piece of a longer conversation
between Dave Plummer and Dave Cutler (RSX11, VMS, WinNT)

https://youtu.be/9K3eMzF6x28?feature=shared

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[TUHS] Re: Dave Cutler recollection about Xenix

[segaloco via TUHS]

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I consistently hear from folks the same about Bill Gates pushing for volume over anything else with Xenix. I wonder to what degree that sort of paradigm shift lead to what we see today with "app stores" and cheap little apps being peddled a dime a dozen. Must be a viable enough business model if people keep doing it, but it makes me die inside. There's also the fact though that as the barrier to entry goes down, well, more folks enter the playing field.

Also I gotta appreciate that Dave Cutler's Bill Gates impersonation is consistent with other folks mocking over the years. He's probably got a pretty thick skin by this point (although the financial success probably helps).

Thanks for the share, there are a few other videos linked there from I assume the same interview, I quite enjoyed them, especially the anecdote of Steve Ballmer's last ditch effort Denny's breakfast to bring Dave on board.

Something this brings back to mind that I always wonder about with Microsoft and their OS choices: So they went with Windows NT for their kernel, scraped the Windows environment off the top of DOS and dolloped it on top. Has there been any explanation over the years why they also decided to keep the MSDOS CLI interface? It's not like the NT kernel couldn't handle simple stuff like a UNIX-y shell, tools like grep and sed, etc. and Microsoft had code in Xenix they probably could've considered using for that. Was it not wanting to have any licensing questions by avoiding anything that smelled like Xenix at all? Or was the consumer base at the time that invested in the MSDOS environment that handing them a Bourne shell with some ubiquitous UNIX tools would've just been unworkable? Feels like a lost opportunity, they could've had their kernel and their desktop environment and still given folks a more robust CLI. Instead stuff like UWIN, Cygwin, etc. had to come along and fill the void. That was something I was hoping he'd talk about when I clicked, but I didn't catch anything particular about the CLI choice.

- Matt G.
------- Original Message -------
On Friday, October 20th, 2023 at 4:27 PM, Skip Tavakkolian <fariborz.t@gmail.com> wrote:

> This might be interesting to some. It is a piece of a longer conversation between Dave Plummer and Dave Cutler (RSX11, VMS, WinNT)
>
> https://youtu.be/9K3eMzF6x28?feature=shared

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[TUHS] Re: Dave Cutler recollection about Xenix

[Steve Nickolas]

On Sat, 21 Oct 2023, segaloco via TUHS wrote:

> Something this brings back to mind that I always wonder about with 
> Microsoft and their OS choices: So they went with Windows NT for their 
> kernel, scraped the Windows environment off the top of DOS and dolloped 
> it on top. Has there been any explanation over the years why they also 
> decided to keep the MSDOS CLI interface? It's not like the NT kernel 
> couldn't handle simple stuff like a UNIX-y shell, tools like grep and 
> sed, etc. and Microsoft had code in Xenix they probably could've 
> considered using for that. Was it not wanting to have any licensing 
> questions by avoiding anything that smelled like Xenix at all? Or was 
> the consumer base at the time that invested in the MSDOS environment 
> that handing them a Bourne shell with some ubiquitous UNIX tools 
> would've just been unworkable? Feels like a lost opportunity, they 
> could've had their kernel and their desktop environment and still given 
> folks a more robust CLI. Instead stuff like UWIN, Cygwin, etc. had to 
> come along and fill the void. That was something I was hoping he'd talk 
> about when I clicked, but I didn't catch anything particular about the 
> CLI choice.

They actually inherited the CLI from OS/2, didn't they?

-uso.

[TUHS] Re: Dave Cutler recollection about Xenix

[Jim Geist]

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Both of them were heavily influenced by DOS. Many of the same commands and
switches from DOS still work today, and pre-powershell scripting is DOS
batch files with lots of extensions added.

On Fri, Oct 20, 2023 at 6:52 PM Steve Nickolas <usotsuki@buric.co> wrote:

> On Sat, 21 Oct 2023, segaloco via TUHS wrote:
>
> > Something this brings back to mind that I always wonder about with
> > Microsoft and their OS choices: So they went with Windows NT for their
> > kernel, scraped the Windows environment off the top of DOS and dolloped
> > it on top. Has there been any explanation over the years why they also
> > decided to keep the MSDOS CLI interface? It's not like the NT kernel
> > couldn't handle simple stuff like a UNIX-y shell, tools like grep and
> > sed, etc. and Microsoft had code in Xenix they probably could've
> > considered using for that. Was it not wanting to have any licensing
> > questions by avoiding anything that smelled like Xenix at all? Or was
> > the consumer base at the time that invested in the MSDOS environment
> > that handing them a Bourne shell with some ubiquitous UNIX tools
> > would've just been unworkable? Feels like a lost opportunity, they
> > could've had their kernel and their desktop environment and still given
> > folks a more robust CLI. Instead stuff like UWIN, Cygwin, etc. had to
> > come along and fill the void. That was something I was hoping he'd talk
> > about when I clicked, but I didn't catch anything particular about the
> > CLI choice.
>
> They actually inherited the CLI from OS/2, didn't they?
>
> -uso.
>

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[TUHS] Re: Dave Cutler recollection about Xenix

[Dave Horsfall]

On Fri, 20 Oct 2023, Jim Geist wrote:

> Both of them were heavily influenced by DOS. Many of the same commands 
> and switches from DOS still work today, and pre-powershell scripting is 
> DOS batch files with lots of extensions added.

Wasn't the DOS interface influenced by CP/M?

-- Dave

[TUHS] Re: Dave Cutler recollection about Xenix

[John Cowan]

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On Fri, Oct 20, 2023 at 8:37 PM segaloco via TUHS <tuhs@tuhs.org> wrote:

 I wonder to what degree that sort of paradigm shift lead to what we see
> today with "app stores" and cheap little apps being peddled a dime a
> dozen.  Must be a viable enough business model if people keep doing it, but
> it makes me die inside.
>

Book publishers made similar complaints about the mass-market paperback
when Robert de Graaf introduced them to the U.S. market in 1939, just in
time for World War II.  They cost about an eighth of the price of the same
book in hard covers and they sold like crazy — 1.5 million in the first
year alone.  Yes, the quality was crap (those early paperbacks are
collectibles now because most of them have fallen apart), but the words
sold books to a huge untapped market who would never have bought a book
before.

Bought any hardbacks lately?

Was it not wanting to have any licensing questions by avoiding anything
> that smelled like Xenix at all?  Or was the consumer base at the time that
> invested in the MSDOS environment that handing them a Bourne shell with
> some ubiquitous UNIX tools would've just been unworkable?
>

I think both of those are pretty likely explanations.  Another possibility
is that the idea was just out of the box for them.  DOS was for one market
and Xenix was for another.

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[TUHS] Re: Dave Cutler recollection about Xenix

[Greg 'groggy' Lehey]

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On Friday, 20 October 2023 at 16:27:40 -0700, Skip Tavakkolian wrote:
> This might be interesting to some. It is a piece of a longer conversation
> between Dave Plummer and Dave Cutler (RSX11, VMS, WinNT)
>
> https://youtu.be/9K3eMzF6x28?feature=shared

This really doesn't seem to have much to do with Xenix.  Yes, he
mentions it briefly, talking about licensing, but that seems to be
all.

FWIW, Xenix preceded DOS as a Microsoft operating system.  From my
personal timeline:

6 September 1980: At Euromicro 80, a conference in London, I heard a
  	    	  presentation about Xenix from a Microsoft person
  	    	  whose name I no longer recall.  It was supposed to
  	    	  have been from Bill Gates, but he had a last-minute
  	    	  cancellation.

December 1980:    I bought a pair of S-100 boards and an operating
	 	  system called 86-DOS from an obscure company in
	 	  Washington state, USA.  I spoke on the phone to a
	 	  Tim Paterson, who assured me that 86-DOS had a
	 	  bright future.  The rest is, of course, history.

June 1981: 	  Byte magazine carried an article from Microsoft
     		  about Xenix.  This was presumably written no later
     		  than May 1981.

August 1981:	  IBM released the PC.

I've done a bit of searching and found this link:
https://computeradsfromthepast.substack.com/p/microsofts-xenix which
tells me that Microsoft (really their SCO) licensed 7th Edition Unix
in 1978 and brought out a product 2 years later.  That seems
plausible.

Does anybody have a programme for Euromicro 80?

More of my recollections at
http://www.lemis.com/grog/diary-sep1980.php#21

Greg
--
Sent from my desktop computer.
Finger grog@lemis.com for PGP public key.
See complete headers for address and phone numbers.
This message is digitally signed.  If your Microsoft mail program
reports problems, please read http://lemis.com/broken-MUA.php

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[TUHS] Re: Dave Cutler recollection about Xenix

[steve jenkin]

Date & event of 1980 Xenix release.

<https://www.tuhs.org/pipermail/tuhs/2021-April/023688.html>

	Xenix was a version of AT&T UNIX, ported and packaged by Microsoft.
	It was first offered for sale to the public in the August 25, 1980 issue of Computerworld.

Source:
	<http://seefigure1.com/2014/04/15/xenixtime.html>

> On 21 Oct 2023, at 17:27, Greg 'groggy' Lehey <grog@lemis.com> wrote:
> 
> I've done a bit of searching and found this link:
> https://computeradsfromthepast.substack.com/p/microsofts-xenix which
> tells me that Microsoft (really their SCO) licensed 7th Edition Unix
> in 1978 and brought out a product 2 years later.  That seems
> plausible.


--
Steve Jenkin, IT Systems and Design 
0412 786 915 (+61 412 786 915)
PO Box 38, Kippax ACT 2615, AUSTRALIA

[TUHS] Re: Dave Cutler recollection about Xenix

[Stuff Received]

On 2023-10-20 19:27, Skip Tavakkolian wrote:
> This might be interesting to some. It is a piece of a longer 
> conversation between Dave Plummer and Dave Cutler (RSX11, VMS, WinNT)
> 
> https://youtu.be/9K3eMzF6x28?feature=shared 
> <https://youtu.be/9K3eMzF6x28?feature=shared>

Is this the full 3-hour interview 
https://www.youtube.com/watch?v=xi1Lq79mLeE ?

S.

[TUHS] Re: Dave Cutler recollection about Xenix

[Paul Ruizendaal]

An interesting set of videos indeed, although I wish they were not all chopped up in 5 minute segments.

> I consistently hear from folks the same about Bill Gates pushing for volume over anything else with Xenix.

That was his business model. His Basic for the 8080 was copied a lot (the famous 1976 open letter to hobbyists) and he shifted to selling bulk licenses to manufacturers. These could then make a bundled hw/sw sale and sidestep the copying. If I understood correctly, in the early days he sold the bulk licenses for a fixed amount, without per copy fees. I suppose this matched his cost structure, so it worked; the leverage and profit came from selling the same to all manufacturers in the market. He also used it in his deal with IBM, beating out Digital Research that wanted per copy fees. Retaining the rights to DOS also matched the business model that had been pioneered for his Basic.

It would seem that the same thinking was at play in the deal for Xenix (which I think preceded the IBM deal). He would spend money once on porting Unix to each of the various next-gen microprocessors of the time (x86, Z8000, 68K, NS32K) and sell (sub-)licenses to hardware manufacturers, who in turn had a right to sub-license binaries to end-users. The deal that he had to negotiate with Bell had to match that business model.

Beyond this, I’m sure that Bill Gates understood the strong network effects in software and the "winner takes all” dynamic that results from it -- hence his focus on volume and market share. However, I don’t think this drove the structure of his 1979 [?] Unix license deal with Bell.

> Something this brings back to mind that I always wonder about with Microsoft and their OS choices: So they went with Windows NT for their kernel, scraped the Windows environment off the top of DOS and dolloped it on top. Has there been any explanation over the years why they also decided to keep the MSDOS CLI interface?

The below site has a very nice summary of Xenix at Microsoft (I’ve linked it a couple of times before):
http://seefigure1.com/2014/04/15/xenixtime.html

About blending Xenix and DOS it says: "As late as the beginning of 1985, there was some debate inside of Microsoft whether Xenix should be the 16-bit “successor” to DOS; for a variety of reasons – mostly having to do with licensing, royalties, and ownership of the code, but also involving a certain amount of ego and politics – MS and IBM decided to pursue OS/2 instead. That marked the end of any further Xenix investment at Microsoft, and the group was left to slowly atrophy.”

Probably that same dynamic was in play for the CLI of Windows NT. Moreover, as you already point out, by the time of NT there were tens of millions of users of DOS, and numerous books, magazines, etc. explaining it. Throwing away that familiarity for unclear benefits (in the eyes of those users) would serve no business purpose. In a way it is the same dynamic that kept C89 and Bash in place for so long: people know it, it is good enough and it works everywhere.

===

Seeing the Cutler interviews reminded me of the old joke that there are only two operating systems left: Unix and VMS (Linux being Unix-family and Windows being VMS-family). I wonder if we will see it narrow down to just one before the hardware changes so much that the concept of an OS changes beyond recognition. My hypothesis would be that an entirely new approach will come first.

[TUHS] Re: Dave Cutler recollection about Xenix

[segaloco via TUHS]

> Seeing the Cutler interviews reminded me of the old joke that there are only two operating systems left: Unix and VMS (Linux being Unix-family and Windows being VMS-family). I wonder if we will see it narrow down to just one before the hardware changes so much that the concept of an OS changes beyond recognition. My hypothesis would be that an entirely new approach will come first.

Android is becoming quite popular for POS systems, which is where I thought we'd be seeing some interesting developments what with all sorts of new hardware the past 5-10 years.  There's some microkernel stuff going on with seL4 out in the world but I don't know what particularly.  Redox is interesting, a Rust-first OS, breaking C hegemony on operating systems, but it's pretty much a novelty right now from what I hear.  That and the actual experience is still meant to be UNIX-y.

At this point I wonder how realistic it would even be to introduce some paradigm shift in OS interface.  The basic syscall interface is still sitting way up under a lot of stuff doing the heavy lifting, I imagine any kernel and runtime environment that intends to actually succeed at present would at the very least need to have interfaces for things like read/write/open/close, seeks, probably fork/exec, sockets, if anyone outside of deeply embedded systems programmers want anything to do with it.  Those discrete operations don't really go away in my mind at least until concepts like files and processes themselves are completely reimagined.  Granted, this exact thing has been done many, many times over the past few decades, but who is running those systems in large-scale production environments?  I can't think of any systems I interact with outside of again deeply embedded applications that aren't WNT (so VMSish), Mach, BSD, or Linux kernel based.  Word on the street (and implied by license notifications) that even modern game console operating systems like PlayStations and the Switch have a good chunk of BSD sitting under them.  And of course mobiles are mostly split Mach (iOS) and Linux (Android).  None of this is to speak to the validity of alternative systems, just observations in my little corner of the world :)

- Matt G.

[TUHS] Re: Dave Cutler recollection about Xenix

[John Cowan]

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On Sat, Oct 21, 2023 at 11:37 AM Paul Ruizendaal <pnr@planet.nl> wrote:

>
> An interesting set of videos indeed, although I wish they were not all
> chopped up in 5 minute segments.
>

The alternative nowadays is for YouTube to chop videos up themselves with
commercials.

The below site has a very nice summary of Xenix at Microsoft (I’ve linked
> it a couple of times before):
> http://seefigure1.com/2014/04/15/xenixtime.html


By this time, there was growing retail demand for Xenix on IBM-compatible
> personal computer hardware, but Microsoft made the strategic decision not
> to sell Xenix in the consumer market; instead, they entered into an
> agreement with a company called the Santa Cruz Operation to package, sell
> and support Xenix for those customers.


That's not entirely true.  The first personal computer I used was an IBM
PC/AT, and I bought MS-branded Xenix (System III) for it.  It was a box
full of floppies, and it came with the MS C compiler (CL.EXE etc.) which
could compile for Xenix or cross-compile for MS-DOS.  That way I could
write command-line programs on Xenix and deliver them for DOS.

 In a way it is the same dynamic that kept C89 and Bash in place for so
> long: people know it, it is good enough and it works everywhere.
>

C89 has plenty of obvious successors; bash does not.

Seeing the Cutler interviews reminded me of the old joke that there are
> only two operating systems left: Unix and VMS (Linux being Unix-family and
> Windows being VMS-family).
>

OS/360 (now in the form of z/OS) is still very much with us.  z/OS is
Posix-certified, but it is fairly distant from Linux, *BSD, or Solaris.
(It is not to be confused with Linux running on System Z virtualized.)

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[TUHS] Re: Dave Cutler recollection about Xenix

[Sebastien F4GRX]

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Hi,

You can enjoy non-chopped up videos by replacing youtube.com by yewtu.be 
in related URLs (easiest way to remember).

Or you can paste a youtube URL in the search box of any Invidious 
instance, like https://invidious.fdn.fr

Other instances listed here in case one of them is down: 
https://docs.invidious.io/instances/

Sebastien


Le 21/10/2023 à 18:40, John Cowan a écrit :
>
>
> On Sat, Oct 21, 2023 at 11:37 AM Paul Ruizendaal <pnr@planet.nl> wrote:
>
>
>     An interesting set of videos indeed, although I wish they were not
>     all chopped up in 5 minute segments.
>
>
> The alternative nowadays is for YouTube to chop videos up themselves 
> with commercials.
>
>     The below site has a very nice summary of Xenix at Microsoft (I’ve
>     linked it a couple of times before):
>     http://seefigure1.com/2014/04/15/xenixtime.html
>
>
>     By this time, there was growing retail demand for Xenix on
>     IBM-compatible personal computer hardware, but Microsoft made the
>     strategic decision not to sell Xenix in the consumer market;
>     instead, they entered into an agreement with a company called the
>     Santa Cruz Operation to package, sell and support Xenix for those
>     customers.
>
>
> That's not entirely true.  The first personal computer I used was an 
> IBM PC/AT, and I bought MS-branded Xenix (System III) for it.  It was 
> a box full of floppies, and it came with the MS C compiler (CL.EXE 
> etc.) which could compile for Xenix or cross-compile for MS-DOS.  That 
> way I could write command-line programs on Xenix and deliver them for DOS.
>
>      In a way it is the same dynamic that kept C89 and Bash in place
>     for so long: people know it, it is good enough and it works
>     everywhere.
>
>
> C89 has plenty of obvious successors; bash does not.
>
>     Seeing the Cutler interviews reminded me of the old joke that
>     there are only two operating systems left: Unix and VMS (Linux
>     being Unix-family and Windows being VMS-family).
>
>
> OS/360 (now in the form of z/OS) is still very much with us.  z/OS is 
> Posix-certified, but it is fairly distant from Linux, *BSD, or 
> Solaris.  (It is not to be confused with Linux running on System Z 
> virtualized.)

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[TUHS] Re: Dave Cutler recollection about Xenix

[Paul Winalski]

On 10/21/23, Paul Ruizendaal <pnr@planet.nl> wrote:
>
> An interesting set of videos indeed, although I wish they were not all
> chopped up in 5 minute segments.
>
>> I consistently hear from folks the same about Bill Gates pushing for
>> volume over anything else with Xenix.
>
> That was his business model.

Exactly.  Microsoft was all about volume.  They were willing to leave
niche markets to third-party software vendors.  Back in the 1990s,
when Microsoft flirted with the idea of selling Windows NT on DEC
Alpha and IBM's PowerPC Microsoft sold its Visual Fortran technology
to DEC, who sold it as Digital Visual Fortran (later to be Compaq
Visual Fortran).  The market for Fortran compilers was too small for
MS.

> Probably that same dynamic was in play for the CLI of Windows NT. Moreover,
> as you already point out, by the time of NT there were tens of millions of
> users of DOS, and numerous books, magazines, etc. explaining it. Throwing
> away that familiarity for unclear benefits (in the eyes of those users)
> would serve no business purpose. In a way it is the same dynamic that kept
> C89 and Bash in place for so long: people know it, it is good enough and it
> works everywhere.

Upward command line compatibility from DOS and Win16 was essential for
NT's acceptance in both the user and developer communities.  Windows
NT was a bit of a hard sell to application developers at first.  It
had a lot of advantages over Win16 (32-bit address space; true
multitasking), but that came at the price of loss of control.  Under
DOS, the OS handed over complete control of hte hardware to your
application and you could do whatever you wanted to, as long as you
left things in a reasonable state when you returned control to the OS.
Things were more disciplined under Win16, but it was common practice
for applications to put hooks into the Win16 code.  With NT, the OS
was protected against tampering by non-privileged code.  You had the
Win32 API to work with and that's it--no hooks in the OS or other
jiggery-pokery.  Some application developers--both inside and outside
of Microsoft--balked at that.

I recall hearing that the DOS command line interface was patterned
after the OS/8 CLI on the PDP-8, which used forward-slash (/) for
command switches.  That's why, when they decided to adopt the Unix
conventions for directories in file pathnames, they had to use
backslash (\) as the directory delimiter.

-Paul W.

[TUHS] Re: Dave Cutler recollection about Xenix

[Jim Geist]

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This is getting a little far afield from Unix history, it's Windows
history, but for similar reasons MS had to make a huge investment in game
technology. Gaming under DOS was already huge by the time Windows 95 came
out, and without proper support for games on Windows it would be hard to
get a lot of people to leave DOS behind. Game developers were wedded to the
idea of the complete control they had over the machine under DOS. Many were
using DOS extenders to break the 640k limit - basically a small operating
system linked into the game that let them access memory over the 1M line.
Hence the Games SDK, later known as DirectX, and some relatively infamous
industry events to court game developers to start porting their games to
Windows.

On Sun, Oct 22, 2023 at 10:45 AM Paul Winalski <paul.winalski@gmail.com>
wrote:

> On 10/21/23, Paul Ruizendaal <pnr@planet.nl> wrote:
> >
> > An interesting set of videos indeed, although I wish they were not all
> > chopped up in 5 minute segments.
> >
> >> I consistently hear from folks the same about Bill Gates pushing for
> >> volume over anything else with Xenix.
> >
> > That was his business model.
>
> Exactly.  Microsoft was all about volume.  They were willing to leave
> niche markets to third-party software vendors.  Back in the 1990s,
> when Microsoft flirted with the idea of selling Windows NT on DEC
> Alpha and IBM's PowerPC Microsoft sold its Visual Fortran technology
> to DEC, who sold it as Digital Visual Fortran (later to be Compaq
> Visual Fortran).  The market for Fortran compilers was too small for
> MS.
>
> > Probably that same dynamic was in play for the CLI of Windows NT.
> Moreover,
> > as you already point out, by the time of NT there were tens of millions
> of
> > users of DOS, and numerous books, magazines, etc. explaining it. Throwing
> > away that familiarity for unclear benefits (in the eyes of those users)
> > would serve no business purpose. In a way it is the same dynamic that
> kept
> > C89 and Bash in place for so long: people know it, it is good enough and
> it
> > works everywhere.
>
> Upward command line compatibility from DOS and Win16 was essential for
> NT's acceptance in both the user and developer communities.  Windows
> NT was a bit of a hard sell to application developers at first.  It
> had a lot of advantages over Win16 (32-bit address space; true
> multitasking), but that came at the price of loss of control.  Under
> DOS, the OS handed over complete control of hte hardware to your
> application and you could do whatever you wanted to, as long as you
> left things in a reasonable state when you returned control to the OS.
> Things were more disciplined under Win16, but it was common practice
> for applications to put hooks into the Win16 code.  With NT, the OS
> was protected against tampering by non-privileged code.  You had the
> Win32 API to work with and that's it--no hooks in the OS or other
> jiggery-pokery.  Some application developers--both inside and outside
> of Microsoft--balked at that.
>
> I recall hearing that the DOS command line interface was patterned
> after the OS/8 CLI on the PDP-8, which used forward-slash (/) for
> command switches.  That's why, when they decided to adopt the Unix
> conventions for directories in file pathnames, they had to use
> backslash (\) as the directory delimiter.
>
> -Paul W.
>

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