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/* access the value using the pointer */

printf("Value of *ip variable: %d\n", *ip );

return 0;
}

When the above code is compiled and executed, it produces the following result:

Address of var variable: bffd8b3c

Address stored in ip variable: bffd8b3c
Value of *ip variable: 20

NULL Pointers
It is always a good practice to assign a NULL value to a pointer variable in case you do
not have an exact address to be assigned. This is done at the time of variable declaration. A
pointer that is assigned NULL is called a null pointer.
The NULL pointer is a constant with a value of zero defined in several standard libraries.
Consider the following program:

#include <stdio.h>

int main ()

{
int *ptr = NULL;

printf("The value of ptr is : %x\n", ptr );

return 0;

}
When the above code is compiled and executed, it produces the following result:

The value of ptr is 0

In most of the operating systems, programs are not permitted to access memory at
address 0 because that memory is reserved by the operating system. However, the memory
address 0 has special significance; it signals that the pointer is not intended to point to an
accessible memory location. But by convention, if a pointer contains the null (zero) value, it is
assumed to point to nothing.

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