Pointers

Using the reference operator & and the dereference operator *, we can create and work with pointers.

A pointer is a data type, just like int, char, or double. The pointer is designed to store an address, which you can obtain using the & operator. To declare a pointer, prepend it with the * character.

In essence, a pointer is a variable that holds the address of another object.

Note

Typically, pointers are named by prefixing the letter p to the name of the object they're pointing to.

When you dereference a pointer, you access the value of the variable it points to.

Main


              1234567891011121314
            
#include <stdio.h>

int main()
{
    int x = 22543; // variable
    
    int* pX = &x; // `pX` is pointer to `x`

    printf("The value of `pX` is %p\n", pX); // value of pointer `pX`
    
    printf("The value of `x` by pointer `pX` is %d\n", *pX); // pointer dereference
    
    return 0;
}

Note

*(&variable) == *pVariable

If you attempt to dereference a null pointer, the compiler will raise an error:

Example provided to showcase the mistake

Main


              12345678910
            
#include <stdio.h>

int main()
{
    int* pX;

    printf("x = %p", pX);

    return 0;
}

Aufgabe

Swipe to start coding

Determine the size of int and double pointers.

Lösung

Wechseln Sie zum Desktop, um in der realen Welt zu übenFahren Sie dort fort, wo Sie sind, indem Sie eine der folgenden Optionen verwenden

War alles klar?

Danke für Ihr Feedback!

Abschnitt 6. Kapitel 3

Pointers

Using the reference operator & and the dereference operator *, we can create and work with pointers.

In essence, a pointer is a variable that holds the address of another object.

Note

Typically, pointers are named by prefixing the letter p to the name of the object they're pointing to.

When you dereference a pointer, you access the value of the variable it points to.

Main


              1234567891011121314
            
#include <stdio.h>

int main()
{
    int x = 22543; // variable
    
    int* pX = &x; // `pX` is pointer to `x`

    printf("The value of `pX` is %p\n", pX); // value of pointer `pX`
    
    printf("The value of `x` by pointer `pX` is %d\n", *pX); // pointer dereference
    
    return 0;
}

Note

*(&variable) == *pVariable

If you attempt to dereference a null pointer, the compiler will raise an error:

Example provided to showcase the mistake

Main


              12345678910
            
#include <stdio.h>

int main()
{
    int* pX;

    printf("x = %p", pX);

    return 0;
}

Aufgabe

Swipe to start coding

Determine the size of int and double pointers.

Lösung

Wechseln Sie zum Desktop, um in der realen Welt zu übenFahren Sie dort fort, wo Sie sind, indem Sie eine der folgenden Optionen verwenden

War alles klar?

Danke für Ihr Feedback!

Abschnitt 6. Kapitel 3

Wechseln Sie zum Desktop, um in der realen Welt zu übenFahren Sie dort fort, wo Sie sind, indem Sie eine der folgenden Optionen verwenden