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

Variable function arguments

As we saw in Chapter 2, Understanding Program Structure, function parameters in C are call-by-value. In other words, when a function is defined to take parameters, the values the function body receives through them are copies of the values given at the function call. The following code copies the values of two values into function parameters so that the function can use those values in its function body:

double RectPerimeter( double h , double w )  {
h += 10.0;
w += 10.0;
return 2*(w + h) ;

int main( void ) {
double height = 15.0;
double width = 22.5;
double perimeter = RectPerimeter( height , width );

In this simple example, the RectPerimeter()function takes two parameters—handw—and returns a value that is based on both of them—the perimeter of the rectangle. WhenRectPerimeter()is called, the handwfunction variables are created and the values ofheightandwidthare assigned to them so thathhas a copy of the...