dcsimg
Login | Register   
RSS Feed
Download our iPhone app
TODAY'S HEADLINES  |   ARTICLE ARCHIVE  |   FORUMS  |   TIP BANK
Browse DevX
Sign up for e-mail newsletters from DevX

By submitting your information, you agree that devx.com may send you DevX offers via email, phone and text message, as well as email offers about other products and services that DevX believes may be of interest to you. DevX will process your information in accordance with the Quinstreet Privacy Policy.


Tip of the Day
Language:
Expertise: Intermediate
Sep 23, 1999

WEBINAR:

On-Demand

Application Security Testing: An Integral Part of DevOps


The offsetof Macro

The macro offsetof (defined in <cstdlib> or <stdlib.h> in C) calculates the offset in bytes of a struct's data member. The following example uses this macro to calculate the offset of two data members in a struct named S:
 
#include <stdlib.h>
struct S
{
  int a;
  int b;
  void * p;
};

int main()
{
  int n = offsetof(S, a);  // 0
  n = offsetof(S, p);  //8
}
Note that offsetof works with POD (Plain Old Data) structs and POD unions. The result of applying the offsetof macro to a field that is a static data member or a function member is undefined.
Danny Kalev
 
Comment and Contribute

 

 

 

 

 


(Maximum characters: 1200). You have 1200 characters left.

 

 

Sitemap
Thanks for your registration, follow us on our social networks to keep up-to-date