From mboxrd@z Thu Jan  1 00:00:00 1970
From: Glynn Clements <glynn@gclements.plus.com>
Subject: Re: data structure question
Date: Mon, 16 May 2005 16:28:06 +0100
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To: gumbold@bonbon.net
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gumbold wrote:

> So char abc[0] actualy pointer to chat?

No, it's an array of char.

> It should be 4 byte long on x86. I can't see it with sizeof.

It's zero bytes long.

If you had:

	struct abc {
	    __u16 a;
	    __u16 b;
	    char abc[4];
	};

then sizeof(struct abc) would be 8 and the offset of abc from the
beginning of the structure would be 4.

With:

	struct abc {
	    __u16 a;
	    __u16 b;
	    char abc[0];
	};

sizeof(struct abc) would be 4 and the offset of abc from the beginning
of the structure would still be 4 (i.e. p->abc refers to the first
byte after the structure).

-- 
Glynn Clements <glynn@gclements.plus.com>