Book Image

Learn C Programming - Second Edition

By : Jeff Szuhay
Book Image

Learn C Programming - Second Edition

By: Jeff Szuhay

Overview of this book

The foundation for many modern programming languages such as C++, C#, JavaScript, and Go, C is widely used as a system programming language as well as for embedded systems and high-performance computing. With this book, you'll be able to get up to speed with C in no time. The book takes you through basic programming concepts and shows you how to implement them in the C programming language. Throughout the book, you’ll create and run programs that demonstrate essential C concepts, such as program structure with functions, control structures such as loops and conditional statements, and complex data structures. As you make progress, you’ll get to grips with in-code documentation, testing, and validation methods. This new edition expands upon the use of enumerations, arrays, and additional C features, and provides two working programs based on the code used in the book. What's more, this book uses the method of intentional failure, where you'll develop a working program and then purposely break it to see what happens, thereby learning how to recognize possible mistakes when they happen. By the end of this C programming book, you’ll have developed basic programming skills in C that can be easily applied to other programming languages and have gained a solid foundation for you to build on as a programmer.
Table of Contents (38 chapters)
1
Part 1: C Fundamentals
10
Part 2: Complex Data Types
19
Part 3: Memory Manipulation
22
Part 4: Input and Output
28
Part 5: Building Blocks for Larger Programs

Understanding function declarations

For the compiler to recognize a function call when it sees it, it must already know about the function. In other words, it must process the function statement's definition before it can process the call to that function. We have seen this behavior in all of our programs up to this point. In each program, we have defined the function and then, later in our program, called it.

This behavior is somewhat limiting since we may want to call a function from anywhere in our program. We don't want to get caught up in its relative position in the program and have to reshuffle the definitions of the functions just to make the compiler happy. The compiler is supposed to work for us, not the other way around.

C provides a way to declare a function so that the compiler knows just enough about the function to be able to process a call to the function before it processes the function definition. These are called function declarations...