World Library  
Flag as Inappropriate
Email this Article

Marc McDonald

Article Id: WHEBN0003486649
Reproduction Date:

Title: Marc McDonald  
Author: World Heritage Encyclopedia
Language: English
Subject: File Allocation Table, Applesoft BASIC, Mark McDonald (politician), Mark McDonald, History of Microsoft
Collection: Living People, Microsoft Employees, Year of Birth Missing (Living People)
Publisher: World Heritage Encyclopedia

Marc McDonald

Marc B. McDonald is an American who was Microsoft's first salaried employee (not counting Monte Davidoff, who wrote the math package for BASIC for a flat fee).

He is credited with designing and implementing the 8-bit File Allocation Table file system for the NCR 8200 data-entry terminal and Microsoft's Standalone Disk BASIC-80 in 1977.

McDonald also developed an 8-bit operating system called M-DOS or MIDAS; the system itself was never released by Microsoft, but its file system (a variant of FAT) influenced Tim Paterson's QDOS.[1][2]

A version of "Standalone Disk Basic" was ported to a Seattle Computer Products 8086 by Bob O'Rear and Tim Paterson was often at Microsoft to aid in the effort. Tim Paterson copied the key aspects of the FAT system (single table, each directory entry containing the head of the file's cluster list, and the last value indicating the number of sectors used in the last cluster) when he implemented the FAT12 file system for his operating system 86-DOS in 1980, which became the basis for MS-DOS and PC DOS in 1981. He made two mistakes in implementation:

  1. In early versions there was not a directory stopper entry. This resulted in reading the entire directory track to discover a file did not exist. On floppies this was a major slowdown.
  2. MS-DOS updates the directory entry and FAT tables in the wrong order when a file is created. By writing the directory first if the system crashed before the FAT tables a dangling reference would be created. This result in a cross-linked file on the next cluster allocation.

McDonald left Microsoft in January 1984, citing a reason that the company had gotten "too big" (Microsoft was at around four hundred employees at that time). He was Asymetrix's first employee where he worked on a Lisp pcode system used internally and redesigned the ToolBook runtime and compiler for ToolBook 3.0. At Design Intelligence, Marc worked on adaptive document design and an expression-based programming language used for layout experiments. He rejoined Microsoft in December 2000 when it bought Design Intelligence.

When McDonald rejoined Microsoft, a number of employees including Bill Gates and Steve Ballmer tried to assign him the employee number "1" but found that the human resources software did not allow this. Instead he was given a badge with all the digits scraped off except "1".[3]

McDonald worked in the

  1. ^ Duncan, Ray (1988). The MS-DOS Encyclopedia - version 1.0 through 3.2. Microsoft Press. p. 9.  
  2. ^ Manes, Stephen; Andrews, Paul (1993). Gates: How Microsoft's Mogul Reinvented an Industry—and Made Himself the Richest Man in America. Doubleday. p. 157.  
  3. ^ scobleizer (2005-09-08). "Marc McDonald - Microsoft's First Employee | scobleizer | Channel 9". Retrieved 2013-06-06. 
  4. ^ The Practical Guide to Defect Prevention. 2007-10-31.  
  5. ^ "Marc McDonald". LinkedIn. Retrieved 2014-05-16. 


See also

McDonald left Microsoft in September 2011. He was with startup MindMode Corp. through 2012, and has been at PaperG since.[5]

. software patents He holds six [4]

This article was sourced from Creative Commons Attribution-ShareAlike License; additional terms may apply. World Heritage Encyclopedia content is assembled from numerous content providers, Open Access Publishing, and in compliance with The Fair Access to Science and Technology Research Act (FASTR), Wikimedia Foundation, Inc., Public Library of Science, The Encyclopedia of Life, Open Book Publishers (OBP), PubMed, U.S. National Library of Medicine, National Center for Biotechnology Information, U.S. National Library of Medicine, National Institutes of Health (NIH), U.S. Department of Health & Human Services, and, which sources content from all federal, state, local, tribal, and territorial government publication portals (.gov, .mil, .edu). Funding for and content contributors is made possible from the U.S. Congress, E-Government Act of 2002.
Crowd sourced content that is contributed to World Heritage Encyclopedia is peer reviewed and edited by our editorial staff to ensure quality scholarly research articles.
By using this site, you agree to the Terms of Use and Privacy Policy. World Heritage Encyclopedia™ is a registered trademark of the World Public Library Association, a non-profit organization.

Copyright © World Library Foundation. All rights reserved. eBooks from Project Gutenberg are sponsored by the World Library Foundation,
a 501c(4) Member's Support Non-Profit Organization, and is NOT affiliated with any governmental agency or department.