Understanding and Using C Pointers

Chapter 4. Pointers and Arrays

An array is a fundamental data structure built into C. A thorough understanding of arrays and their use is necessary to develop effective applications. Misunderstandings of array and pointer usage can result in hard-to-find errors and less than optimal performance in applications. Array and pointer notations are closely related to each other and can frequently be used interchangeably in the right context.

A common misconception is that an array and a pointer are completely interchangeable. An array name is not a pointer. Although an array name can be treated as a pointer at times, and array notation can be used with pointers, they are distinct and cannot always be used in place of each other. Understanding this difference will help you avoid incorrect use of these notations. For example, although the name of an array used by itself will return the array’s address, we cannot use the name by itself as the target of an assignment.

Arrays support many parts of an application and can be single or multidimensional. In this chapter, we will address the fundamental aspects of arrays as they relate to pointers to provide you with a deep understanding of arrays and the various ways they can be manipulated with pointers. You will see their use in more advanced contexts throughout the book.

We start with a quick review of arrays and then examine the similarities and differences between array and pointer notation. Arrays can be created using malloc type functions. ...