Variable structure size -- ANSI ?

[Will Crowder]

In article <6246 at male.EBay.Sun.COM>, harry at matilda.uk.sun.com (Harry
Protoolis - Sun EHQ) writes:

> |> Michael N Johnston writes:
> |> ]>struct foo {
> |> ]>unsigned short recsize;
> |> ]>unsigned short num;
> |> ]>char info [24];
> |> ]>byte flags;
> |> ]>char filename[1]
> |> ]>};
> |> ]>Where, foo.filename is a placeholder for a variable length string.
> |> 
> 
> A question really, does the standard *guarantee* the physical order of
> structure elements ? I looked in K&R 2 and couldn't find anything.

The ANSI standard guarantees that elements of a structure will be allocated
in the order declared.  However, there may be any amount of padding between
structure elements.  But yes, for

	struct foo {
		int a;
		int b;
	};

&foo.b is guaranteed to be greater then &foo.a.  Also, &foo is guaranteed
to be equal to &foo.a.

|> Harry
|> --- 

Hope this helps,

Will

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