C Programming help .....wtf ?!?!

[Vu Pham]

> -----Original Message-----
> From: linux-users-bounces at linux-sxs.org 
> [mailto:linux-users-bounces at linux-sxs.org] On Behalf Of Ben Duncan
> Sent: Tuesday, January 25, 2005 2:16 PM
> To: Linux tips and tricks
> Subject: Re: C Programming help .....wtf ?!?!
> 
> Why does the sizeof( struct _dummymenu) on the below return 8 ?
> 
> 
>    typedef struct _dummymenu
>         {
>         char d_char ;
>         int d_sumnumber ;
>         } DummyMenu ;
> 
> Yet if I do one a structure like this:
> 
> typedef struct _dummymenu
>         {
>         char a_char ;
>         char b_char ;
>         char c_char ;
>         } DummyMenu ;
> 
> it returns 3 ......
> 

I think because of the memory aligmnet option of the compiler. You can try
#pragma pack(n) to change the default alignment, like

#pragma pack(1)	// set the alignment to 1, all vars are adjacent to each
other
typedef struct _dummymenu
{
        char d_char ;
         int d_sumnumber ;
} DummyMenu ;


Vu