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IEEE admits its MS-DOS history revisionist is in Microsoft's pay

CP/M, QDOS diff man is Redmond 'expert witness'

The IEEE's Spectrum magazine has admitted that a recent contributor, who wrote an eyebrow-raising revisionist history of MS-DOS, is paid by Microsoft.

Eagle-eyed readers have spotted that the notorious article about the development of Microsoft's early operating system, which we discussed here, is now prefaced with the following message:

Editor’s Note: Upon publication, this article failed to properly disclose the connection between its author, Bob Zeidman, and Microsoft Corp., a key subject of the story. Mr. Zeidman is currently retained by Microsoft as an expert witness in Motorola Mobility v. Microsoft. IEEE Spectrum regrets the omission.

In what purported to be a "forensic" investigation of MS-DOS lineage, using his own glorified diff grep software analyser, Zeidman compared the source code of 1970s operating system CP/M and QDOS, the latter a CP/M clone that Microsoft acquired to create MS-DOS.

Unsurprisingly, Zeidman found no matches of identical code in the rival software; there was no smoking gun that indicated one was a direct copy of the other. His report made derogatory remarks about CP/M author Gary Kildall, such as the suggestion that he committed suicide. In fact, Kildall died three days after a late-night fall in a bar, in which time he was admitted to hospital, and discharged, twice.

In his 2005 book They Made America, former Sunday Times editor Sir Harold Evans gave the first comprehensive account of the saga in a profile of the late Kildall. He concluded that QDOS was a "rip off" of CP/M. QDOS author Tim Paterson sued for defamation and lost. Paterson has always denied using Digital Research's CP/M source code to create QDOS. ®

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