From mboxrd@z Thu Jan  1 00:00:00 1970
From: Glynn Clements <glynn@gclements.plus.com>
Subject: Re: data structure question
Date: Sun, 15 May 2005 12:02:17 +0100
Message-ID: <17031.11321.223828.203914@gargle.gargle.HOWL>
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To: gumbold@bonbon.net
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gumbold wrote:

> why somebody wants to write such thing
> struct abc {
>     __u16 a;
>     __u16 b;
>     char abc[0];
> } __attribute__((packed));
> Specialy for zerod array of chars.

A structure which ends with a zero-length array is intended for use as
the "header" for a variable-sized block of data, e.g.:

	struct abc *new_abc(__u16 a, __u16 b, const char *string)
	{
		int len = strlen(string);
		struct abc *p = malloc(sizeof(struct abc) + len + 1);
	
		p->a = a;
		p->b = b;
		memcpy(p->abc, string, len + 1);
	
		return p;
	}

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