From: "A. Sinan Unur" <asu1 AT cornell DOT edu>
Newsgroups: comp.os.msdos.djgpp
Subject: Re: Why does sizeof give me...
Date: Wed, 06 Aug 1997 22:17:00 -0400
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Insomnia wrote:
> 
>         At least part of your problem is most likely due to gcc's 
> behavior of 32-bit alligning fields in a structure.

that is correct but a large part should be because int's are 32 bit
rather than 16.

>   struct mystruct {
>     char element1 __attribute__ ((packed));
>     int  element2 __attribute__ ((packed));
>     .....
>     };
>         Hope this helps.  Corrections/constructive criticism welcome, 
> as are flames

not a flame. in declaring structs as packed, you do not have to apply
the attribute to each element of the struct, you can apply it to the
struct as a whole:

#include <stdio.h>
#include <stdlib.h>

int main(void)
{
 typedef struct a
 {
   short x;
   int   y;
 } a;

 struct p
 {
  short x;
  int y;
 } __attribute__((packed)) p;

 printf("%lu\n", sizeof(a));
 printf("%lu\n", sizeof(p));

return 0;
}

output:

D:\djgpp\C>test
8
6





-- 
   Sinan
 
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