Jeff Duntemann - Assembly Language Step-by-Step: Programming with Linux

Assembly Language Step-by-Step

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Copyright 2009 by Jeff Duntemann

Published by Wiley Publishing, Inc., Indianapolis, Indiana

Published simultaneously in Canada

ISBN: 978-0-470-49702-9

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To the eternal memory of

Kathleen M. Duntemann, Godmother

19201999

who gave me books when all I could do was put teeth marks on them.

There are no words for how much I owe you!

About the Author

Jeff Duntemann is a writer, editor, lecturer, and publishing industry analyst. In his thirty years in the technology industry he has been a computer programmer and systems analyst for Xerox Corporation, a technical journal editor for Ziff-Davis Publications, and Editorial Director for Coriolis Group Books and later Paraglyph Press. He is currently a technical publishing consultant and also owns Copperwood Press, a POD imprint hosted on lulu.com. Jeff lives with his wife Carol in Colorado Springs, Colorado.

Credits

Executive Editor

Carol Long

Project Editor

Brian Herrmann

Production Editor

Rebecca Anderson

Copy Editor

Luann Rouff

Editorial Director

Robyn B. Siesky

Editorial Manager

Mary Beth Wakefield

Production Manager

Tim Tate

Vice President and Executive Group Publisher

Richard Swadley

Vice President and Executive Publisher

Barry Pruett

Associate Publisher

Jim Minatel

Project Coordinator, Cover

Lynsey Stanford

Proofreader

Dr. Nate Pritts, Word One

Indexer

J&J Indexing

Cover Image

Jupiter Images/Corbis/Lawrence Manning

Acknowledgments

First of all, thanks are due to Carol Long and Brian Herrmann at Wiley, for allowing this book another shot, and then making sure it happened, on a much more aggressive schedule than last time.

As for all three previous editions, I owe Michael Abrash a debt of gratitude for constant sane advice on many things, especially the arcane differences between modern Intel microarchitectures.

Although they might not realize it, Randy Hyde, Frank Kotler, Beth, and all the rest of the gang on alt.lang.asm were very helpful in several ways, not least of which was hearing and answering requests from assembly language newcomers, thus helping me decide what must be covered in a book like this and what need not.

Finally, and as always, a toast to Carol for the support and sacramental friendship that has enlivened me now for 40 years, and enabled me to take on projects like this and see them through to the end.

Introduction: Why Would You Want to Do That ?

It was 1985, and I was in a chartered bus in New York City, heading for a press reception with a bunch of other restless media egomaniacs. I was only beginning my media career (as Technical Editor for PC Tech Journal ) and my first book was still months in the future. I happened to be sitting next to an established programming writer/guru, with whom I was impressed and to whom I was babbling about one thing or another. I won't name him, as he's done a lot for the field, and may do a fair bit more if he doesn't kill himself smoking first.

But I happened to let it slip that I was a Turbo Pascal fanatic, and what I really wanted to do was learn how to write Turbo Pascal programs that made use of the brand-new Microsoft Windows user interface. He wrinkled his nose and grimaced wryly, before speaking the Infamous Question:

Why would you want to do that ?

I had never heard the question before (though I would hear it many times thereafter) and it took me aback. Why? Because, well, becauseI wanted to know how it worked .

Heh. That's what C's for.

Further discussion got me nowhere in a Pascal direction. But some probing led me to understand that you couldn't write Windows apps in Turbo Pascal. It was impossible. Orthe programming writer/guru didn't know how. Maybe both. I never learned the truth. But I did learn the meaning of the Infamous Question.

Note well: When somebody asks you, Why would you want to do that ? what it really means is this: You've asked me how to do something that is either impossible using tools that I favor or completely outside my experience, but I don't want to lose face by admitting it. Sohow bout those Blackhawks?

I heard it again and again over the years:

Q: How can I set up a C string so that I can read its length without scanning it?

A: Why would you want to do that?

Q: How can I write an assembly language subroutine callable from Turbo Pascal?

A: Why would you want to do that?

Q: How can I write Windows apps in assembly language?

A: Why would you want to do that?

You get the idea. The answer to the Infamous Question is always the same, and if the weasels ever ask it of you, snap back as quickly as possible, Because I want to know how it works.