C++ For Dummies®, 6th Edition

Chapter 8. Taking a First Look at C++ Pointers

In This Chapter

• Addressing variables in memory

• Declaring and using pointer variables

• Recognizing the inherent dangers of pointers

• Passing pointers to functions

• Allocating objects off the heap (whatever that is)

So far, the C++ language has been fairly conventional compared with other programming languages. Sure, some computer languages lack (il-)logical operators like those in Chapter 4, and C++ has its own unique symbols for things, but there's been nothing new in the way of concepts. C++ really separates itself from the crowd in its use of pointer variables. A pointer is a variable that "points at" other variables. I realize that's a circular argument, but suspend your disbelief at least until you can get into the chapter.

This chapter introduces the pointer variable type. It begins with some concept definitions, flows through pointer syntax, and then introduces some of the reasons for the pointer mania that grips the C++ programming world.

Variable Size

My weight goes up and down all the time, but here I'm really referring to the size of a variable, not my own variable size. Memory is measured in bytes or bits. The keyword sizeof returns the size of its argument in bytes. The following program uses this to determine the size of the different variable types:

// VariableSize - output the size of each type of // variable #include <cstdio> #include <cstdlib> #include <iostream> using namespace std; int main(int nNumberofArgs, char* pszArgs[]) ...