<<split from https://cboard.cprogramming.com/showthread.php?t=40936>>

If I call this offsetof() macro in a function:
Code:
int func([type] struct_name, [type] member)
{
   ...
   x = offsetof(struct_name, member);
   ...
}
What should be the [type]s in the function prototype? That is, what are the types of the parameters of offsetof()?