Understanding and Using C Pointers

Chapter 5. Pointers and Strings

Strings can be allocated to different regions of memory and pointers are commonly used to support string operations. Pointers support the dynamic allocation of strings and passing strings to a function. A good understanding of pointers and their use with strings enables programmers to develop valid and efficient applications.

Strings are a common component of many applications and are a complex topic. In this chapter, we will explore the various ways of declaring and initializing strings. We will examine the use of literal pools in C applications and their impact. In addition, we will look at common string operations, such as comparing, copying, and concatenating strings.

Strings are regularly passed and returned to functions as pointers to char. When we pass a string, we can do so either as a pointer to a char or a pointer to a constant char. The latter approach protects the string from modification within the function. Many examples used in this chapter provide additional illustrations of the concepts developed in the function chapter. They differ as they do not need to pass their size to a function.

A string may also be returned from a function to fulfill a request. This string may be passed to the function to be modified or allocated from within the function. We could also return a statically allocated string. Each of these approaches will be examined.

We will also examine the use of function pointers and how they can assist sorting operations. Understanding ...