From: Avery P. <ape...@ni...> - 2004-10-22 19:22:36
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On Fri, Oct 22, 2004 at 08:08:18PM +0100, Keir Fraser wrote: > > Plan 9 works just fine without packed structs, as do the many operating > > systems written by people using compilers that didn't do packed structs > > either, or even compilers that always packed structs (V6 C). All these > > systems twiddled bits just fine. > > I'm interested to know how. How do you define a network header layout, > for example, and how do you access subfields? e.g., is there an > explicit IDL with integration into the compiler? Typically fixed-format data structures are done by simply accessing the data as a char[] array instead of a struct. This may not be as pretty, but it compiles down into the same machine code and it's 100% portable. (And you can do it pretty decently with some preprocessor macros.) Have fun, Avery |