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From: Simon Wright <simon@pushface.org>
Newsgroups: comp.lang.ada
Subject: Re: Using representation clauses in networking software
Date: Sun, 15 Aug 2010 20:15:49 +0100
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Date: 2010-08-15T20:15:49+01:00
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"Dmitry A. Kazakov" <mailbox@dmitry-kazakov.de> writes:

> When using representation clauses? In order to use them you have two
> parameters in the equation: the internal endianness and external
> endianness. How can it be statically independent on the former (=portable)?
> Well, with conditional expressions of Ada 201X, maybe, it could be possible
> to describe. But I don't want to be one to maintain that mess. I'd better
> stick to good old means.

Yes, indeed.

Stick to network-byte-order on the wire, define messages explicitly,
preferably with a pictorial representation that is extremely clear as to
which byte is sent in which order and how this corresponds to machine
storage.

I don't think you can take too much trouble with specifying any sort of
interface; endianness differences just make matters more critical.