Can I do arithmetic on void * pointers in C?

Question

is this valid

void *p = &X; /* some thing */
p += 12;

and if so what does p now point to? I have (third party) code that does this (an

Answer 1

Your guess is correct.

In the standard ISO C99, section 6.2.5 paragraph 26, it declares that void pointers and character pointers will have the same representation and alignment requirements (paraphrasing).