Define a macro for byte offset of a given field in a structure.

Question

AK · Accepted Answer

#define GETBYTEOFFSET(type ,member) ( &((type *)0->member) - &(type *)0)

Rahul · Answer

That is incorrect,
&(type *)0 will not even compile, its an absolute (constant) value , it needs a memory location, and a valid one too. 

(int)& (((type*)0)->member) should suffice, C compiler will then take it as an address relative to start of structure and hence will give the offset.

AK · Answer

-->args
x - field
y - structure

#define GETBYTEOFFSET(x,y)
{ \
   &(y) - &(y.x); \ 
}

Apple

Pregunta de entrevista de Apple

Respuestas de entrevistas

Empresas seguidas

Búsquedas de empleo