POINTER

                                      POINTER

Pointer is a special variable that holds the address of another variable.

Declaration of pointer :

            syntax: datatype * pointername ;

example : int * p ;

                float * ptr ;

  

A pointer always meant to hold the address not an ordinary variable .

'*' is called value at address operator .

Normal variable provides direction access to their own values whereas pointer provides indirect access to the value of variable whose address it stores.

BAD POINTER : 

When a pointer is first declared , it does not contain a valid address . The pointer is uninitialized or bad pointer.

Each pointer must be assigned  a valid address before it can support pointer operations. 

Before that pointer is bad and shouldnot be used .

Null pointer :

Pointer that does not point any value.

Void pointer :

It is syntatically incorrect to assign the address of any data type variable to any other data type variable.

A void pointer is a special kind of pointer that can hold address of a variable of any data type .

Syntax : void * pointername ;

 

The keyword  void represents that this pointer donot have any type associated with it and type assignment must be used to change void pointer to a concrete data type we refer .