Write Portable Code: A Guide to Developing Software for Multiple Platforms

274 Pages·2005·4.903 MB·English

by  Brian Hook

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WRITE PORTABLE CODE
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WRITE PORTABLE
CODE
An Introduction to Developing
Software for Multiple Platforms
by Brian Hook
San Francisco
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WRITE PORTABLE CODE. Copyright © 2005 by Brian Hook.
All rights reserved. No part of this work may be reproduced or transmitted in any form or by any means, electronic or
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Publisher: William Pollock
Managing Editor: Karol Jurado
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Library of Congress Cataloging-in-Publication Data
Hook, Brian, 1971-
Write portable code : an introduction to developing software for multiple platforms / Brian Hook.--
1st ed.
p. cm.
Includes bibliographical references and index.
ISBN 1-59327-056-9
1. Software compatibility. 2. Computer software--Development. I. Title.
QA76.76.C64H66 2005
005.1--dc22
2005012981
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For my wife, Jennifer
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B R I E F C O N T E N T S
Preface.........................................................................................................................xv
Acknowledgments.........................................................................................................xix
Introduction: The Art of Portable Software Development.......................................................1
Chapter 1: Portability Concepts........................................................................................7
Chapter 2: ANSI C and C++..........................................................................................19
Chapter 3: Techniques for Portability...............................................................................25
Chapter 4: Editing and Source Control............................................................................63
Chapter 5: Processor Differences....................................................................................77
Chapter 6: Floating Point...............................................................................................91
Chapter 7: Preprocessor..............................................................................................109
Chapter 8: Compilers..................................................................................................119
Chapter 9: User Interaction..........................................................................................141
Chapter 10: Networking..............................................................................................149
Chapter 11: Operating Systems....................................................................................155
Chapter 12: Dynamic Libraries.....................................................................................175
Chapter 13: Filesystems...............................................................................................187
Chapter 14: Scalability................................................................................................197
Chapter 15: Portability and Data..................................................................................201
Chapter 16: Internationalization and Localization...........................................................207
Chapter 17: Scripting Languages..................................................................................213
Chapter 18: Cross-Platform Libraries and Toolkits............................................................219
Appendix A: POSH.....................................................................................................223
Appendix B: The Rules for Portability.............................................................................229
References..................................................................................................................233
Index.........................................................................................................................235
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C O N T E N T S I N D E T A I L
PREFACE xv
This Book’s Audience ..............................................................................................xvi
Online Resources ..................................................................................................xviii
ACKNOWLEDGMENTS xix
INTRODUCTION
THE ART OF PORTABLE SOFTWARE DEVELOPMENT 1
The Benefits of Portability ..........................................................................................2
Elements of the Platform ............................................................................................3
The Problem with Assumptions ...................................................................................4
Coding Standards ....................................................................................................4
The Framework for Portable Programming ...................................................................5
1
PORTABILITY CONCEPTS 7
Portability Is a State of Mind, Not a State ....................................................................7
Develop Good Portability Habits ................................................................................8
Good Habits Trump Specific Knowledge of Bugs or Standards ......................................9
Port Early and Port Often ..............................................................................9
Develop in a Heterogeneous Environment ......................................................9
Use a Variety of Compilers .........................................................................10
Test on Several Platforms ............................................................................10
Support Multiple Libraries ...........................................................................11
Plan Portability for a New Project .............................................................................11
Make Portability Easy ................................................................................11
Choose a Reasonable Level of Portability .....................................................12
Don’t Wed Your Project to Proprietary Products ............................................14
Port Old Code .......................................................................................................16
Assume Code Is Not Portable Until It Has Been Ported ...................................16
Modify Only the Bare Essentials ..................................................................16
Plan Your Attack .......................................................................................17
Document Everything in Revision Control ......................................................17
2
ANSI C AND C++ 19
Why Not Another Language? ..................................................................................19
C and C++ Provide Low-Level Access ..........................................................20
C and C++ Compile to Native Code ...........................................................20
C and C++ Dialects................................................................................................21
Portability and C/C++ ............................................................................................22