THE MS-DOS(R) ENCYCLOPEDIA
Ray Duncan, General Editor
Foreword by Bill Gates
A Division of Microsoft Corporation
16011 NE 36th Way, Box 97017, Redmond, Washington 98073-9717
Copyright (C) 1988 by Microsoft Press
All rights reserved. No part of the contents of this book may be reproduced
or transmitted in any form or by any means without the written permission
of the publisher.
Library of Congress Cataloging in Publication Data
The MS-DOS encyclopedia : versions 1.0 through 3.2 /
editor, Ray Duncan.
1. MS-DOS (Computer operating system) I. Duncan, Ray, 1952-
II. Microsoft Press.
QA76.76.063M74 1988 87-21452
Printed and bound in the United States of America.
1 2 3 4 5 6 7 8 9 RMRM 8 9 0 9 8 7
Distributed to the book trade in the United States by Harper & Row.
Distributed to the book trade in Canada by General Publishing Company, Ltd.
Distributed to the book trade outside the
United States and Canada by Penguin Books Ltd.
Penguin Books Ltd., Harmondsworth, Middlesex, England
Penguin Books Australia Ltd., Ringwood, Victoria, Australia
British Cataloging in Publication Data available
IBM(R), IBM AT(R), PS/2(R), and TopView(R) are registered trademarks of
International Business Machines Corporation. GW-BASIC(R), Microsoft(R),
MS(R), MS-DOS(R), SOFTCARD(R), and XENIX(R) are registered trademarks of
Microsoft Press gratefully acknowledges permission to reproduce material
Page 4: Courtesy The Computer Museum.
Pages 5, 11, 42: Intel 4004, 8008, 8080, 8086, and 80286 microprocessor
photographs. Courtesy Intel Corporation.
Page 6: Reprinted from Popular Electronics, January 1975
Copyright (C) 1975 Ziff Communications Company.
Page 13: Reprinted with permission of Rod Brock.
Page 16: Reprinted with permission of The Seattle Times Copyright (C) 1983.
Pages 19, 34, 42: IBM PC advertisements and photographs of the PC, PC/XT,
and PC/AT reproduced with permission of International Business Machines
Corporation Copyright (C) 1981, 1982, 1984. All rights reserved.
Page 21: "Big IBM's Little Computer" Copyright (C) 1981 by The New York
Times Company. Reprinted by permission.
"IBM Announces New Microcomputer System" Reprinted with permission of
InfoWorld Copyright (C) 1981.
"IBM really gets personal" Reprinted with permission of Personal Computing
Copyright (C) 1981.
"Personal Computer from IBM" Reprinted from DATAMATION Magazine, October
1981 Copyright (C) by Cahners Publishing Company.
"IBM's New Line Likely to Shake up the Market for Personal Computers"
Reprinted by permission of The Wall Street Journal Copyright (C) Dow Jones
& Company, Inc. 1981. All Rights Reserved.
Page 36: "Irresistible DOS 3.0" and "The Ascent of DOS" Reprinted from
PC Tech Journal, December 1984 and October 1986. Copyright (C) 1984, 1986
Ziff Communications Company.
"MS-DOS 2.00: A Hands-On Tutorial" Reprinted by permission of PC World from
Volume 1, Issue 3, March 1983, published at 501 Second Street, Suite 600,
San Francisco, CA 94107.
Special thanks to Bob O'Rear, Aaron Reynolds, and Kenichi Ikeda.
Editor-in-Chief: Susan Lammers
Editorial Director: Patricia Pratt
Senior Editor: Dorothy L. Shattuck
Senior Technical Editor: David L. Rygmyr
Special Projects Editor: Sally A. Brunsman
Editorial Coordinator: Sarah Hersack
Associate Editors and Technical Editors: Pamela Beason, Ann
Becherer, Bob Combs, Michael Halvorson, Jeff Hinsch, Dean Holmes, Chris
Kinata, Gary Masters, Claudette Moore, Steve Ross, Roger Shanafelt, Eric
Stroo, Lee Thomas, JoAnne Woodcock
Copy Chief: Brianna Morgan. Proofreaders: Kathleen Atkins,
Julie Carter, Elizabeth Eisenhood, Matthew Eliot, Patrick Forgette, Alex
Hancock, Richard Isomaki, Shawn Peck, Alice Copp Smith
Editorial Assistants: Wallis Bolz, Charles Brod, Stephen
Brown, Pat Erickson, Debbie Kem, Susanne McRhoton, Vihn Nguyen, Cheryl
Index: Shane-Armstrong Information Services
Production: Larry Anderson, Jane Bennett, Rick Bourgoin,
Darcie S. Furlan, Nick Gregoric, Peggy Herman, Lisa Iversen, Rebecca
Johnson, Ruth Pettis, Russell Steele, Jean Trenary, Joy Ulskey
Marketing and Sales Director: James Brown
Director of Production: Christopher D. Banks
Publisher: Min S. Yee
Ray Duncan, General Editor Duncan received a B.A. in Chemistry from
the University of California, Riverside, and an M.D. from the
University of California, Los Angeles, and subsequently received
specialized training in Pediatrics and Neonatology at the Cedars-Sinai
Medical Center in Los Angeles. He has written many articles for
personal computing magazines, including BYTE, PC Magazine, Dr. Dobb's
Journal, and Softalk/PC, and is the author of the Microsoft Press book
Advanced MS-DOS. He is the founder of Laboratory Microsystems
Incorporated, a software house specializing in FORTH interpreters and
Steve Bostwick Bostwick holds a B.S. in Physics from the University
of California, Los Angeles, and has over 20 years' experience in
scientific and commercial data processing. He is president of Query
Computing Systems, Inc., a software firm specializing in the creation
of systems for applications that interface microcomputers with
specialized hardware. He is also an instructor for the UCLA Extension
Department of Engineering and Science and helped design their popular
Microprocessor Hardware and Software Engineering Certificate Program.
Keith Burgoyne Born and raised in Orange County, California,
Burgoyne began programming in 1974 on IBM 370 mainframes. In 1979, he
began developing microcomputer products for Apples, TRS-80s, Ataris,
Commodores, and IBM PCs. He is presently Senior Systems Engineer at
Local Data of Torrance, California, which is a major producer of IBM
3174/3274 and System 3X protocol conversion products. His previous
writing credits include numerous user manuals and tutorials.
Robert A. Byers Byers is the author of the bestselling Everyman's
Database Primer. He is presently involved with the Emerald Bay
database project with RSPI and Migent, Inc.
Thom Hogan During 11 years working with personal computers, Hogan
has been a software developer, a programmer, a technical writer, a
marketing manager, and a lecturer. He has written six books, numerous
magazine articles, and four manuals. Hogan is the author of the
forthcoming Microsoft Press book PC Programmer's Sourcebook.
Jim Kyle Kyle has 23 years' experience in computing. Since 1967, he
has been a systems programmer with strong telecommunications
orientation. His interest in microcomputers dates from 1975. He is
currently MIS Administrator for BTI Systems, Inc., the OEM Division of
BanTec Inc., manufacturers of MICR equipment for the banking
industry. He has written 14 books and numerous magazine articles
(mostly on ham radio and hobby electronics) and has been primary Forum
Administrator for Computer Language Magazine's CLMFORUM on CompuServe
since early 1985.
Gordon Letwin Letwin is Chief Architect, Systems Software, Microsoft
Corporation. He is the author of Inside OS/2, published by Microsoft
Charles Petzold Petzold holds an M.S. in Mathematics from Stevens
Institute of Technology. Before launching his writing career, he
worked 10 years in the insurance industry, programming and teaching
programming on IBM mainframes and PCs. He is the author of the
Microsoft Press book Programming Windows 2.0, a contributing editor to
PC Magazine, and a frequent contributor to the Microsoft Systems
Chip Rabinowitz Rabinowitz has been a programmer for 11 years. He is
presently chief programmer for Productivity Solutions, a microcomputer
consulting firm based in Pennsylvania, and has been Forum
Administrator for the CompuServe MICROSOFT SIG since 1986.
Jim Tomlin Tomlin holds a B.S. and an M.S. in Mathematics. He has
programmed at Boeing, Microsoft, and Opcon and has taught at Seattle
Pacific University. He now heads his own company in Seattle, which
specializes in PC systems programming and industrial machine vision
Richard Wilton Wilton has programmed extensively in PL/1, FORTRAN,
FORTH, C, and several assembly languages. He is the author of
Programmer's Guide to PC & PS/2 Video Systems, published by Microsoft
Van Wolverton A professional writer since 1963, Wolverton has had
bylines as a newspaper reporter, editorial writer, political
columnist, and technical writer. He is the author of Running MS-DOS
and Supercharging MS-DOS, both published by Microsoft Press.
William Wong Wong holds engineering and computer science degrees
from Georgia Tech and Rutgers University. He is director of PC Labs
and president of Logic Fusion, Inc. His interests include operating
systems, computer languages, and artificial intelligence. He has
written numerous magazine articles and a book on MS-DOS.
JoAnne Woodcock Woodcock, a former senior editor at Microsoft Press,
has been a writer for Encyclopaedia Britannica and a freelance and
project editor on marine biological studies at the University of
Southern California. She is co-editor (with Michael Halvorson) of
XENIX at Work and co-author (with Peter Rinearson) of Microsoft Word
Style Sheets, both published by Microsoft Press.
Special Technical Advisor
Paul Allen Michael Geary David Melin John Pollock
Steve Ballmer Bob Griffin Charles Mergentime Aaron Reynolds
Reuben Borman Doug Hogarth Randy Nevin Darryl Rubin
Rob Bowman James W. Johnson Dan Newell Ralph Ryan
John Butler Kaamel Kermaani Tani Newell Karl Schulmeisters
Chuck Carroll Adrian King David Norris Rajen Shah
Mark Chamberlain Reed Koch Mike O'Leary Barry Shaw
David Chell James Landowski Bob O'Rear Anthony Short
Mike Colee Chris Larson Mike Olsson Ben Slivka
Mike Courtney Thomas Lennon Larry Osterman Jon Smirl
Mike Dryfoos Dan Lipkie Ridge Ostling Betty Stillmaker
Rachel Duncan Marc McDonald Sunil Pai John Stoddard
Kurt Eckhardt Bruce McKinney Tim Paterson Dennis Tillman
Eric Evans Pascal Martin Gary Perez Greg Whitten
Rick Farmer Estelle Mathers Chris Peters Natalie Yount
Bill Gates Bob Matthews Charles Petzold Steve Zeck
Foreword by Bill Gates
Preface by Ray Duncan
Section I: The Development of MS-DOS
Section II: Programming in the MS-DOS Environment
Part A: Structure of MS-DOS
Article 1: An Introduction to MS-DOS
Article 2: The Components of MS-DOS
Article 3: MS-DOS Storage Devices
Part B: Programming for MS-DOS
Article 4: Structure of an Application Program
Article 5: Character Device Input and Output
Article 6: Interrupt-Driven Communications
Article 7: File and Record Management
Article 8: Disk Directories and Volume Labels
Article 9: Memory Management
Article 10: The MS-DOS EXEC Function
Part C: Customizing MS-DOS
Article 11: Terminate-and-Stay-Resident Utilities
Article 12: Exception Handlers
Article 13: Hardware Interrupt Handlers
Article 14: Writing MS-DOS Filters
Article 15: Installable Device Drivers
Part D: Directions of MS-DOS
Article 16: Writing Applications for Upward Compatibility
Article 17: Windows
Part E: Programming Tools
Article 18: Debugging in the MS-DOS Environment
Article 19: Object Modules
Article 20: The Microsoft Object Linker
Section III: User Commands
User commands are listed in alphabetic order. This section includes
ANSI.SYS, BATCH, CONFIG.SYS, DRIVER.SYS, EDLIN, RAMDRIVE.SYS, and
Section IV: Programming Utilities
Section V: System Calls
System calls are listed in numeric order.
Appendix A: MS-DOS Version 3.3
Appendix B: Critical Error Codes
Appendix C: Extended Error Codes
Appendix D: ASCII and IBM Extended ASCII Character Sets
Appendix E: EBCDIC Character Set
Appendix F: ANSI.SYS Key and Extended Key Codes
Appendix G: File Control Block (FCB) Structure
Appendix H: Program Segment Prefix (PSP) Structure
Appendix I: 8086/8088/80286/80386 Instruction Sets
Appendix J: Common MS-DOS Filename Extensions
Appendix K: Segmented (New) .EXE File Header Format
Appendix L: Intel Hexadecimal Object File Format
Appendix M: 8086/8088 Software Compatibility Issues
Appendix N: An Object Module Dump Utility
Appendix O: IBM PC BIOS Calls
Commands and System Calls