Preface

Welcome to the C programming language. This book presents leading-edge computing technologies for software development professionals.

At the heart of the book is the Deitel signature “live-code approach.” We present concepts in the context of complete working programs, rather than in code snippets. Each code example is followed by one or more sample executions. Read the online Before You Begin section (www.deitel.com/books/cfp/cfp_BYB.pdf) to learn how to set up your computer to run the 130 code examples and your own C programs. All the source code is available at www.deitel.com/books/cfp and www.pearsonhighered.com/deitel. Use the source code we provide to run every program as you study it.

This book will give you an informative, challenging and entertaining introduction to C. If you have questions, send an e-mail to [email protected]—we’ll respond promptly. For book updates, visit www.deitel.com/books/cfp, join our communities on Facebook (www.deitel.com/deitelfan), Twitter (@deitel), Google+ (gplus.to/deitel) and LinkedIn (bit.ly/deitelLinkedIn), and subscribe to the Deitel^® Buzz Online newsletter (www.deitel.com/newsletter/subscribe.html).

• Coverage of the New C standard. The book is written to the new C standard, often referred to as C11 or simply “the C standard” since its approval in 2011. Support for the new standard varies by compiler. Most of our readers use either the GNU gcc compiler—which supports many of the key features in the new standard—or the Microsoft Visual C++ compiler. Microsoft supports only a limited subset of the features that were added to C in C99 and C11—primarily the features that are also required by the C++ standard. To accommodate all of our readers, we placed the discussion of the new standard’s features in optional, easy-to-use-or-omit sections and in Appendix E, Additional Features of the C Standard. We’ve also replaced various deprecated capabilities with newer preferred versions as a result of the new C standard.

• Chapter 1. We’ve included test-drives that show how to run a command-line C program on Microsoft Windows, Linux and Mac OS X.

• Secure C Programming Sections. We’ve added notes about secure C programming to many of the C programming chapters. We’ve also posted a Secure C Programming Resource Center at www.deitel.com/SecureC/. For more details, see the section A Note About Secure C Programming in this Preface.

• Focus on Performance Issues. C is often favored by designers of performance-intensive applications such as operating systems, real-time systems, embedded systems and communications systems, so we focus intensively on performance issues.

• All Code Tested on Windows and Linux. We’ve tested every example program using Visual C++^® and GNU gcc in Windows and Linux, respectively.

• Sorting: A Deeper Look. Sorting is an interesting problem because different sorting techniques achieve the same final result but they can vary hugely in their consumption of memory, CPU time and other system resources—algorithm performance is crucial. We begin our presentation of sorting in Chapter 6 and, in Appendix D, we present a deeper look. We consider several algorithms and compare them with regard to their memory consumption and processor demands. For this purpose, we introduce Big O notation, which indicates how hard an algorithm may have to work to solve a problem. Appendix D discusses the selection sort, insertion sort and recursive merge sort.

• Debugger Appendices. We include Visual Studio^® and GNU gdb debugging appendices.

• Order of Evaluation. We discuss subtle order of evaluation issues to help you avoid errors.

• C++-Style // Comments. We use the newer, more concise C++-style // comments in preference to C’s older style /*...*/ comments.

• C Standard Library. Section 1.3 references en.cppreference.com/w/c where you can find thorough searchable documentation for the C Standard Library functions.

The CERT^® Coordination Center (www.cert.org) was created to analyze and respond promptly to attacks. CERT—the Computer Emergency Response Team—publishes and promotes secure coding standards to help C programmers and others implement industrial-strength systems that avoid the programming practices that open systems to attack. The CERT standards evolve as new security issues arise.

Our code conforms to various CERT recommendations as appropriate for a book at this level. If you’ll be building C systems in industry, consider reading two books by Robert Seacord—The CERT C Secure Coding Standard (Addison-Wesley Professional, 2009) and Secure Coding in C and C++ (Addison-Wesley Professional, 2013). The CERT guidelines are available free online at www.securecoding.cert.org. Seacord, a technical reviewer for this book, also provided specific recommendations on each of our new Secure C Programming sections. Mr. Seacord is the Secure Coding Manager at CERT at Carnegie Mellon University’s Software Engineering Institute (SEI) and an adjunct professor in the Carnegie Mellon University School of Computer Science.

The Secure C Programming sections at the ends of Chapters 2–13 discuss many important topics, including testing for arithmetic overflows, using unsigned integer types, new more secure functions in the C standard’s Annex K, the importance of checking the status information returned by standard-library functions, range checking, secure random-number generation, array bounds checking, techniques for preventing buffer overflows, input validation, avoiding undefined behaviors, choosing functions that return status information vs. similar functions that do not, ensuring that pointers are always NULL or contain valid addresses, preferring C functions to preprocessor macros, and more.

Syntax Shading. For readability, we syntax shade the code, similar to the way most IDEs and code editors syntax color code. Our syntax-shading conventions are:

Click here to view code image

Code Highlighting. We place gray rectangles around the key code segments in each source-code program.

Using Fonts for Emphasis. We place the key terms and the index’s page reference for each defining occurrence in bold text for easy reference. We emphasize on-screen components in the bold Helvetica font (e.g., the File menu) and C program text in the Lucida font (for example, int x = 5;).

Objectives. Each chapter includes a list of chapter objectives.

Illustrations/Figures. Abundant charts, tables, line drawings, flowcharts, programs and program outputs are included.

Programming Tips. We include programming tips to help you focus on important aspects of program development. These tips and practices represent the best we’ve gleaned from a combined eight decades of programming and corporate training experience.

Index. We’ve included an extensive index, which is especially useful when you use the book as a reference. Defining occurrences of key terms are highlighted with a bold page number.

or contact us at [email protected]. You can also access our LiveLessons videos if you have a subscription to Safari Books Online (www.safaribooksonline.com).

Well, there you have it! C11 is a powerful programming language that will help you write high-performance programs quickly and effectively. C11 scales nicely into the realm of enterprise systems development to help organizations build their business-critical and mission-critical information systems. As you read the book, we would sincerely appreciate your comments, criticisms, corrections and suggestions for improving the text. Please address all correspondence to:

We’ll respond promptly and post corrections and clarifications on:

We hope you enjoy working with C for Programmers with an Introduction to C11 as much as we enjoyed writing it!

Paul and Harvey Deitel

Dr. Harvey Deitel, Chairman and Chief Strategy Officer of Deitel & Associates, Inc., has more than 50 years of experience in the computer field. Dr. Deitel earned B.S. and M.S. degrees in Electrical Engineering (studying computing) from MIT and a Ph.D. in Mathematics (studying computer science) from Boston University. He has extensive industry and college teaching experience, including earning tenure and serving as the Chairman of the Computer Science Department at Boston College before founding Deitel & Associates, Inc., in 1991 with his son, Paul Deitel. Dr. Deitel has delivered hundreds of professional programming seminars to major corporations, academic institutions, government organizations and the military. The Deitels’ publications have earned international recognition, with translations published in traditional Chinese, simplified Chinese, Korean, Japanese, German, Russian, Spanish, French, Polish, Italian, Portuguese, Greek, Urdu and Turkish.

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