Pointer Pointers In C with examples

Pointer Pointers In C Programming

Simple Pointer Definition

Pointers in C language is a variable that stores/points the address of another variable is called pointer in C,

Pointer To Pointer

When one pointer variable is used to store the address of another pointer variable, therefore, such type of pointer is known as pointer to pointer variable.

Pointer to pointer variable is also called as double pointer in C programming.

Declaration of pointer-to-pointer

  int **ptr ;

Note:

To store the address of normal variable we use single pointer variable.
To store the address of single pointer variable we use double pointer variable.

Example 1:

Output:

 Address of normal variable 'a' = 2293316
 Address of pointer variable '*ptr1' = 2293304
 Address of pointer-to-pointer '**ptr2' = 2293296

Example 2:

Output:

 Address of number variable is 22fe44
 Address of p variable is 22fe44
 Value of *p variable is 20
 Address of p2 variable is 22fe38
 Value of **p2 variable is 20
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