[Tfug] OT: sizeof *part* of a struct

[Mike Fitzgibbon]

If payload is always at the end, try offsetof(Foo, payload).
Otherwise it's probably easiest to define a type for payload:
typedef union {
   stuff
   otherstuff
} Payload;

On Thu, 1 Apr 2010, Bexley Hall wrote:

> Hi,
>
> I'm trying to find safe syntax for the following:
>
> typedef struct foo {
>   blah-blah-blah;
>   union {
>      stuff
>      otherstuff
>   } payload;
> } Foo;
>
> #define OVERHEAD (sizeof(Foo) - sizeof(Foo.payload))
>
> Suggestions?
>
> Thx,
> --don
>
>

-- 
Mike Fitzgibbon			MRFitz at ns.arizona.edu