Interview Questions

What is a void pointer?

C Interview Questions and Answers


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What is a void pointer?

A void pointer is a C convention for a raw address. The compiler has no idea what type of object a void Pointer really points to. If you write
int *ip;
ip points to an int. If you write
void *p;
p doesn’t point to a void!
In C and C++, any time you need a void pointer, you can use another pointer type. For example, if you have a char*, you can pass it to a function that expects a void*. You don’t even need to cast it. In C (but not in C++), you can use a void* any time you need any kind of pointer, without casting. (In C++, you need to cast it).
A void pointer is used for working with raw memory or for passing a pointer to an unspecified type.
Some C code operates on raw memory. When C was first invented, character pointers (char *) were used for that. Then people started getting confused about when a character pointer was a string, when it was a character array, and when it was raw memory.

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