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 scope for functions

The scoping rules for functions are considerably simpler than for variables. Function declarations are very similar to external variable declarations. As we have variables that must be declared before they can be accessed, functions must be declared or prototyped before they can be called, and—like external variables—function declarations also have a file scope. They can be called anywhere within a source file after they have been prototyped or defined.

We have already seen how we can define functions in such a way that prototypes are not needed. We simply define them before they are ever called. Most often, however, it is far more convenient to simply declare function prototypes at the beginning of source files. When this is done, functions can be called from anywhere within the file, and there is no need to worry about whether a function has been declared before calling it.

To make functions extend beyond their compilation...