Quick Answer: What Can’T You Do On A Void Pointer?

Can a pointer be void?

A void pointer is a pointer that has no associated data type with it.

A void pointer can hold address of any type and can be typcasted to any type..

What is a pointer variable?

A pointer however, is a variable that stores the memory address as its value. A pointer variable points to a data type (like int or string ) of the same type, and is created with the * operator.

When would you use a void pointer?

void pointers should be used any time the contents of a block of data is not important. For example when copying data the contents of a memory area is copied but the format of the data is not important.

Can a structure contain pointer to itself?

You cannot declare a structure type that contains itself as a member, but you can declare a structure type that contains a pointer to itself as a member. A structure variable definition contains an optional storage class keyword, the struct keyword, a structure tag, a declarator, and an optional identifier.

What is size of void pointer?

The size of void pointer varies system to system. If the system is 16-bit, size of void pointer is 2 bytes. If the system is 32-bit, size of void pointer is 4 bytes. If the system is 64-bit, size of void pointer is 8 bytes.

Why void is used in C?

void (C++) When used as a function return type, the void keyword specifies that the function does not return a value. When used for a function’s parameter list, void specifies that the function takes no parameters. When used in the declaration of a pointer, void specifies that the pointer is “universal.”

What is a self referencing pointer?

Self Referential structures are those structures that have one or more pointers which point to the same type of structure, as their member. … In the above example ‘link’ is a pointer to a structure of type ‘node’. Hence, the structure ‘node’ is a self-referential structure with ‘link’ as the referencing pointer.

What is generic pointer and its need?

A void pointer is a special pointer that can point to object of any type. A void pointer is typeless pointer also known as generic pointer. void pointer is an approach towards generic functions and generic programming in C. Note: Writing programs without being constrained by data type is known as generic programming.

Why do we typecast malloc?

Advantages to casting: The cast allows for pre-1989 versions of malloc that originally returned a char * . Casting can help the developer identify inconsistencies in type sizing should the destination pointer type change, particularly if the pointer is declared far from the malloc() call.

What will happen when structure is declared?

What will happen when the structure is declared? Explanation: While the structure is declared, it will not be initialized, So it will not allocate any memory. … Explanation: The structure declaration with open and close braces and with a semicolon is also called structure specifier.

Can we assign null to void pointer?

Infact you can assign NULL /0 to pointer of any type. So NULL is nullpointer constant.

What is the advantage of declaring void pointers?

What is the advantage of declaring void pointers? The void pointer can be converted anytime into any generic type pointer by casting operator.

What is a void pointer and how do we use it?

Void pointer is a generic pointer that can be used to point another variable of any data type. Void pointer can store the address of variable belonging to any of the data type. So, void pointer is also called as general purpose pointer.

How do you cast a void pointer?

printf(“%d”,*(int*)a); // If user inputs 1, then he means the data is an integer and type casting is done accordingly. printf(“%c”,*(char*)a); // Typecasting for character pointer. Another important point you should keep in mind about void pointers is that – pointer arithmetic can not be performed in a void pointer.

How do I print a void pointer?

The pointer value itself is rarely interesting, but you can print it with printf(“%p\n”, out); . The %p formatting specifier is for void * . printf(“%p\n”, out); is the correct way to print a (void*) pointer.

What is a void * pointer?

The void pointer in C is a pointer which is not associated with any data types. It points to some data location in the storage means points to the address of variables. It is also called general purpose pointer. In C, malloc() and calloc() functions return void * or generic pointers.

What is generic pointer?

It make sense to have a pointer type that can hold the address of any data type. When a variable is declared as being a pointer to type void it is known as a generic pointer.

What is a NULL pointer in C?

A null pointer is a pointer which points nothing. Some uses of the null pointer are: a) To initialize a pointer variable when that pointer variable isn’t assigned any valid memory address yet. b) To pass a null pointer to a function argument when we don’t want to pass any valid memory address.