Re: newby.-interpreting C

[Nir Dremer <mailing@dremer.org>]

this specific attributes is intended in order to avoid structure
alignment in memory.
The compiler is performing alignment to any allocation to be a
multiplication of 4k.
in order to disable this alignment __attribute__ packed is being used.

usually this is being used when working with networking:
if you have a structure of 5k and you will send it you will actually
send 8k.

attributes information:
http://www.unixwiz.net/techtips/gnu-c-attributes.html


cheers

On Mon, 2004-12-20 at 20:07 +0100, soraberri wrote:
> Hi all,
> 
> Anyone could give me the meaning of this definition? Is the 
> __attribute__ stuff what scares me. If you feel like I'm too 
> desoriented, please tell me what should I know first.
> 
> typedef struct {
> 	uint8_t b[6];
> } __attribute__((packed)) bdaddr_t;
> 
> thanks very much
> 
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