Book Image

Learn C Programming

By : Jeff Szuhay
Book Image

Learn C Programming

By: Jeff Szuhay

Overview of this book

C is a powerful general-purpose programming language that is excellent for beginners to learn. This book will introduce you to computer programming and software development using C. If you're an experienced developer, this book will help you to become familiar with the C programming language. This C programming book takes you through basic programming concepts and shows you how to implement them in C. Throughout the book, you'll create and run programs that make use of one or more C concepts, such as program structure with functions, data types, and conditional statements. You'll also see how to use looping and iteration, arrays, pointers, and strings. As you make progress, you'll cover code documentation, testing and validation methods, basic input/output, and how to write complete programs in C. By the end of the book, you'll have developed basic programming skills in C, that you can apply to other programming languages and will develop a solid foundation for you to advance as a programmer.
Table of Contents (33 chapters)
Section 1: C Fundamentals
Section 2: Complex Data Types
Section 3: Memory Manipulation
Section 4: Input and Output
Section 5: Building Blocks for Larger Programs

Exploring function return values

A function statement can return a value to its caller. It does so from within its function block. The caller is not required to use the returned value and can ignore it. In Hello, world!, the printf() function call actually does return a value but we ignore it.

When a function statement is specified with a return type, then it must return a value of that type. Such a specification consists of two parts:

  • The return type of the function, given before the name of the function
  • The return value, which is of the same type as the return type

In main.c, int—short for integer or whole number—is the type specified that the main()function must return to its caller. Immediately before the closing brace, we find thereturn 0;statement, which returns the 0integer value. In most OS system calls (such as Unix, Linux, macOS, and Windows), a return value of 0 by convention typically means no error...