C Programming - Pointers - Discussion

Void data type does not have values.

@Rahul.

Expression within sizeof() not solved.

int i=1,j;

j=sizeof(++i + j++);
printf("%d%d",i,j);

What will be the output of this program a getting confuse please explain it.

void is a return type (void *) is represented by NULL pointer.

You can use the 0(zero) at the NULL, but in the program you may have the value 0(zero) which is required for the program, to differentiate that in <stdio.h> or <stddef.h> they have predefined this NULL as macro with,

#define NULL (void*)0.

Just to avoid the confusions of the value 0(zero), is value zero or NULL pointer.

The void Type:

The void type specifies that no value is available. It is used in three kinds of situations:

S.N. Types and Description:

1. Function returns as void

There are various functions in C who do not return value or you can say they return void. A function with no return value has the return type as void. For example void exit (int status);

2. Function arguments as void

There are various functions in C who do not accept any parameter. A function with no parameter can accept as a void. For example int rand(void);

3. Pointers to void

A pointer of type void * represents the address of an object, but not its type. For example a memory allocation function void *malloc( size_t size ); returns a pointer to void which can be casted to any data type.

Hi all,

As of I know this is the explanation.

Void pointer is a type of pointer which can store any type of value and null pointer is a pointer which does not point to anything. So here it is mentioned as "(void*)0" means we are declaring a void pointer holding 0 as its value which is an indirect representation of null pointer.

Thanks,

If the zero is not indicate it returns null value only.

It is pointer which return nothing or null. It is use in those function which simply print something.

What is difference between null pointer and generic pointer?