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

Allocating dynamic memory

Memory allocation routines are declared in stdlib.h and are a part of the C Runtime Library. There are two very similar allocation routines – malloc() and calloc() – which are used to allocate a new block of memory from the heap. The main difference between malloc() and calloc() is that calloc() clears the memory block it allocates, whereas malloc() only does allocation. There is a third routine, realloc(), which is used to resize an existing block of heap memory. These functions have the following prototypes:

          malloc( size_t size );
void* calloc( size_t count , size_t size );

void* realloc( void *ptr , size_t size);

Somewhere in stdlib.h, size_t is defined as follows:

          type unsigned int size_t;

Each of these functions returns a void* pointer to a block of memory in the heap space...