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

Variable function arguments

As we saw in Chapter 2Understanding Program Structure, function parameters in C are call by value. In other words, when a function is defined to take parameters, the values that 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 – h and w – and returns a value that is based on both of them –...