[cctalk] Re: MS-DOS

-----Original Message----- From: David Wise via cctalk <cctalk(a)classiccmp.org> Sent: Tuesday, July 30, 2024 2:01 AM To: Murray McCullough via cctalk <cctalk(a)classiccmp.org> Cc: David Wise <d44617665(a)hotmail.com> Subject: [cctalk] Re: MS-DOS I think Windows 2000 is NT-based.

Dave Wise ________________________________ From: Fred Cisin via cctalk <cctalk(a)classiccmp.org> Sent: Monday, July 29, 2024 5:21 PM To: Murray McCullough via cctalk <cctalk(a)classiccmp.org> Cc: Fred Cisin <cisin(a)xenosoft.com> Subject: [cctalk] Re: MS-DOS On Mon, 29 Jul 2024, Murray McCullough via cctalk wrote: Ah, but there is so much more to the story, which deserves an entire

the history. More than you wanted to know? : (but even more details available if you

want them) Tim Paterson, of Seattle Computer Products was developing 8086 hardware,

CP/M-86 was delayed. So, he wrote a temporary place-holder to use instead

CP/M-86 until CP/M-86 became available. That was called "QDOS", "Quick

Dirty Operating System". Later it became known as "SCP-DOS" and/or

Then came the "culture clash" between IBM and Digital Research (previously known as "Intergalctic digital Research"). That has been documented elsewhere; some claim that there was not a culture clash, nor an error. So, Microsoft (possibly Bill Gates personally) went down the street to

Computer Products, and bought an unlimited license for 86-DOS "that we can sell to our [un-named] client" Tim Paterson, who later opened "Falcon Technologies" and Seattle Computer Products both also retained licenes to be able to sell "the operating

Note that the version was not specified, as to whether such license would include rights to sell updated versions; that error (failure to specify

future/derivative products were included) has been repeated elsewhere (cf. Apple/Microsoft) Microsoft also hired Tim Paterson to maintain and update "MS-DOS". Microsoft sold a license to IBM, where it became PC-DOS. And, it was available through Lifeboat as "86-DOS" In August 1981, when the PC (5150) was released, IBM started selling

But digital Research was not happy with IBM selling a copy of their

system. In those days, selling a copy was legal, if the internal code was not

(hence the development of "clean-room reverse engineering") It wasn't

Lotus/Paperback Software (Adam Osborne) lawsuit that "look and feel"

copyrightable. So, IBM agreed to also sell CP/M-86 IN ADDITION to selling PC-DOS. . . . and sold UCSD P-System. But CP/M-86 was STILL not ready, so everybody bought PC-DOS, many of whom planned to switch to CP/M-86 when it became available. But, when CP/M-86 was finally ready, the price was $240 vs $40 for PC-DOS. There are arguments about whether IBM or Digital Research set that price. Although, if that price was IBM's idea, then why did Digital Research

$240 for copies sold through other sources (such as Lifeboat)? Initially MS-DOS and PC-DOS differed only in name and trivial items, such

"IO.SYS" and "MSDOS.SYS" being renamed "IBMBIO.COM" and "IBMDOS.COM" When changes were made, Microsoft's and IBM's version numbers were separated. Thus 1.00 was the same for both IBM released PC-DOS 1.10, and Microsoft released MS-DOS 1.25 2.00 was the same for both 2.10 VS 2.11 (IBM needed trivial changes to 2.00 to deal with the

slow Qumetrak 142 disk drives in the PC-Junior and "portable" 3.00 was the same 3.10, adding network support and the "network redirector for CD-ROMs 3.20 VS 3.21, adding "720K" 3.5" drive support 3.30 VS 3.31, BUT 3.31 was the first to support larger than 32Mebibyte

4.00 and 4.01 IBM/Microsoft did not provide third party vendors enough advanced warning, so Norton Utilities, etc. did not work on 4.00 (NOT 4.00 did not work with Norton Utilities!) 5.00 In 6.00 each company bundled a whole bunch of third party stuff (such as

compression) and each got them from different sources. When Microsoft's disk compression was blamed for serious problems caused

SMARTDRV, Microsoft released 6.20 (repaired and reliability improved from 6.00). Then 6.21 and 6.22 as a result of Microsoft's legal case with Stac

Please note that MS-DOS/PC-DOS ALWAYS had a version number, a period, and then a TWO DIGIT DECIMAL sub-version number. THAT is what is stored internally. Thus, 1.10 is stored as ONE.TEN (01h.0Ah), 3.31 is actually THREE.Thirty-ONE (03h.1Fh), etc. If there had ever actually been a "1.1" or "3.2", those would have been

(1.01) and 03h.02h (3.02), etc. "1.1" was NOT the same as "1.10", nor "3.2" the same as "3.20", otherwise

minor changes would be confused with serious changes, as happened when some people called 4.01 "four point one". Later still, Seattle Computer Products was on the rocks. There was some speculation that AT&T might buy it, to get the DOS license (and not have

royalties per copy!). After some legal animosity, Microsoft did the right

smart thing, and bought Seattle Computer Products, thus closing that vulnerability. Windows originally started as an add-on command processor and user

on top of DOS. Windows95 made that invisibly seamless, so the user never

a DOS prompt without explicitly asking for it. Windows 95 still contained

(7.00), but the user never saw it. Gordon Letwin at Microsoft developed OS/2. But Microsoft sold it off to

and it became known as an IBM product. Microsoft used some key technology from it in developing WindowsNT. Within Microsoft's offerings, NT competed with non-NT windows, such as Windows95, Windows98, and Windows2000. Windows[NT] Vista, XP, 7, 8, 9, 10, 11 continued, and the old Windows was "deprecated'. Naming a version after the year it is released is great for sales in the

and a serious liability in subsequent years, unless there is actually

new version every year (as automobiles do) -- Grumpy Ol' Fred cisin(a)xenosoft.com