Mastering Algorithms with C

Chapter 2. Pointer Manipulation

In C, for any type T, we can form a corresponding type for variables that contain addresses in memory where objects of type T reside. One way to look at variables like this is that they actually “point to” the objects. Thus, these variables are called pointers. Pointers are very important in C, but in many ways, they are a blessing and a curse. On the one hand, they are a powerful means of building data structures and precisely manipulating memory. On the other hand, they are easy to misuse, and their misuse often leads to unpredictably buggy software; thus, they come with a great deal of responsibility. Considering this, it is no surprise that pointers embody what some people love about C and what other people hate. Whatever the case, to use C effectively, we must have a thorough understanding of them. This chapter presents several topics on pointers and introduces several of the techniques using pointers that are employed throughout this book.

This chapter covers:

Pointer fundamentals

Including one of the best techniques for understanding pointers: drawing diagrams. Another fundamental aspect of pointer usage is learning how to avoid dangling pointers.

Storage allocation

The process of reserving space in memory. Understanding pointers as they relate to storage allocation is especially important because pointers are a virtual carte blanche when it comes to accessing memory.

Aggregates and pointer arithmetic

In C, aggregates are structures and arrays. Pointer ...