¿Podemos desreferenciar el puntero vacío?

Can we dereference void pointer?

1) void pointers cannot be dereferenced.

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.

Dereferencing is used to access or manipulate data contained in memory location pointed to by a pointer. *(asterisk) is used with pointer variable when dereferencing the pointer variable, it refers to variable being pointed, so this is called dereferencing of pointers.

The compiler will not let you dereference a void* pointer because it does not know the size of the object pointed to. You can of course use a void*, and it’s very handy for writing generic code in C without templates, but you need to typecast your pointer to the right type before you dereference it.

Because the void pointer is used to cast the variables only, So pointer arithmetic can’t be done in a void pointer.

That dereference causes undefined behavior. You can not dereference a void pointer because it doesn’t have a type, first you need to cast it (int *)lVptr, then dereference it * (int *)lVptr. A void pointer is just that, a pointer to a void (nothing definable). Useful in some instances.

Any pointer may be implicitly converted to a void*, so that cast does nothing and you are left with a pointer to void just as you began with. You’ll need to declare it as an int*. Note that the cast to an int* is also unnecessary, for the same reason you don’t have to (and should not) cast the return value of malloc in C.

Here we have assigned the name of the array one_d to the void pointer vp. Since the base type of one_d is a pointer to int or (int*), the void pointer vp is acting like a pointer to int or (int*).

If this statement appears at file scope, instance will be initialized with a null pointer when the program starts. If this statement appears inside a function, its value is undefined. The variable must be initialized to point to a valid MY_STRUCT variable, or to dynamically allocated space, before it can be dereferenced. For example: