Feeds

Microsoft's MS-DOS is 30 today

Kudos to QDOS

Build a business case: developing custom apps

MS-DOS is 30 years old today. Well, kind of. On 27 July 1981, Microsoft gave the name MS-DOS to the disk operating system it acquired on that day from Seattle Computer Products (SCP), a hardware company owned and run by a fellow called Rod Brock.

SCP developed what it at various times called QDOS and 86-DOS to run on a CPU card it had built based on Intel's 8086 processor.

MS-DOS 1.19

Command line: MS-DOS 1.19 still running after all these years

The company had planned to use Digital Research's CP/M-86 operating system, then still in development. But, having released the card in November 1979 - it shipped with an 8086-compatible version Microsoft's Basic language interpreter-cum-operating system - and reached April 1980 without CP/M-86 becoming available to bundle, SCP decided it had to create its own OS for the card.

Enter, in August 1980, QDOS. It really did stand for Quick and Dirty Operating System. That's actually what it was: a basic but serviceable OS good for coding and running programs written in 8086 assembly language - the x86 instruction set. It was written by SCP's Tim Paterson, who had joined the company as a programmer a couple of years previously and began work on it in April 1980.

Seattle Computer Products Ad

On the cards: Seattle Computer Products advertises its wares

Some observers later claimed that QDOS too closely resembled CP/M for comfort. Paterson himself would later say that QDOS' design criteria specifically included the abililty to support programs written for CP/M and compiled for the 8086. That's not at all surprising given that SCP undoubtedly saw QDOS as a temporary stand in until Digital Research (DR) shipped CP/M-86.

The picture we have today is muddied by the claims that IBM originally wanted to use CP/M-86 in its first personal computer. IBM and DR famously failed to come to terms that would allow CP/M-86 to be bundled with the PC, and IBM turned to Microsoft for an alternative. Digital Research founder Gary Kildall, who died in 1994, would later allege that Microsoft's product was a rip off, fuelling plagiarism claims that Paterson has always denied - he reverse engineered it.

CP/M-86

The competition: CP/M-86 in action
Source: Wikipedia

Update My fellow Reg hack Andrew Orlowski points out that, no matter what Paterson says, the US court ruled against the programmer in a defamation lawsuit he brought against publisher Little Brown for claiming the origins of QDOS were not clear-cut.

Back in 1980, Paterson continued to evolve QDOS through the year, the OS being renamed 86-DOS - it was now evidently no longer viewed as a rough-and-ready stand-in - between September and December 1980. Accounts differ as to when the name - and the OS' status - was switched, but December is the date Paterson himself gave during a Softtalk interview published just a few years later.

The essential guide to IT transformation

More from The Register

next story
So, Apple won't sell cheap kit? Prepare the iOS garden wall WRECKING BALL
It can throw the low cost race if it looks to the cloud
End of buttons? Apple looks to patent animating iPhone sidewalls
Filing suggests handset with display strips
One step closer to ROBOT BUTLERS: Dyson flashes vid of VACUUM SUCKER bot
Latest cleaner available for world+dog in September
Samsung Gear S: Quick, LAUNCH IT – before Apple straps on iWatch
Full specs for wrist-mounted device here ... but who'll buy it?
Apple promises to lift Curse of the Drained iPhone 5 Battery
Have you tried turning it off and...? Never mind, here's a replacement
Now that's FIRE WIRE: HP recalls 6 MILLION burn-risk laptop cables
Right in the middle of Burning Mains Man week
Apple's iWatch? They cannae do it ... they don't have the POWER
Analyst predicts fanbois will have to wait until next year
Reg man looks through a Glass, darkly: Google's toy ploy or killer tech specs?
Tip: Put the shades on and you'll look less of a spanner
HUGE iPAD? Maybe. HUGE ADVERTS? That's for SURE
Noo! Hand not big enough! Don't look at meee!
prev story

Whitepapers

Top 10 endpoint backup mistakes
Avoid the ten endpoint backup mistakes to ensure that your critical corporate data is protected and end user productivity is improved.
Implementing global e-invoicing with guaranteed legal certainty
Explaining the role local tax compliance plays in successful supply chain management and e-business and how leading global brands are addressing this.
Backing up distributed data
Eliminating the redundant use of bandwidth and storage capacity and application consolidation in the modern data center.
The essential guide to IT transformation
ServiceNow discusses three IT transformations that can help CIOs automate IT services to transform IT and the enterprise
Next gen security for virtualised datacentres
Legacy security solutions are inefficient due to the architectural differences between physical and virtual environments.