From mboxrd@z Thu Jan  1 00:00:00 1970
From: Helmut Djurkin <djh@tscheinig.com>
Subject: Re: structure size
Date: Wed, 05 Mar 2003 08:27:26 +0000
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To: Mohammed Khalid Ansari <khalid@ncst.ernet.in>
Cc: linux c programming mailing list <linux-c-programming@vger.kernel.org>

hi,
it's the alignment.

with gcc and this:
struct node {
	/* member here */
} __attribute__((packed));

you will get the your "collective sizes".


Mohammed Khalid Ansari wrote:
> Hi,
> 
> why the sizeof sturcture is alway greater than the collective sizes of all 
> the elements in it.
> 
> eg
> struct node {
> 	int	a;
> 	char	c;
> 	int	b;
> };
> 
> int main()
> {
> 	printf ("%d\n", sizeof (struct node));
> 	return 0;
> }
> 
> 
> it prints 12 in my case.
> 
> where is the catch.
>