What's meaning of these volatile with pointers in C ?

volatile void * ptr;

Whether `ptr` is `volatile` or it points to the `volatile location`.

So the actual doubt is :
Is the same thing applied to the above declaration as it applied with `const` qualifier ?

Little explanation will help me a lot.

A [Microsoft explanation][1]:

> The volatile keyword specifies that the value associated with the name that follows can be modified by actions other than those in the user application.

The volatile keyword is useful for declaring objects in shared memory that can be accessed by multiple processes.

[1]:

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It's a pointer to volatile data. If the pointer itself should be volatile but not the data it points at, you'd use:

void * volatile ptr;

So yes, it works the same way as the `const` modifier.

Both `const` and `volatile` are [type qualifiers][1] (they're the only type qualifiers in C, in fact). The syntax for using them is identical.

[1]:

[To see links please register here]