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From: Adam Beneschan <adam@irvine.com>
Newsgroups: comp.lang.ada
Subject: Re: Encapsulating Ada.Direct_IO
Date: Thu, 18 Nov 2010 11:48:49 -0800 (PST)
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On Nov 18, 10:21=A0am, "Peter C. Chapin" <pcc482...@gmail.com> wrote:

> I'm thinking about the very common case when one is trying to read a
> file that has a format defined by some third party. For example the
> specification of the format might say, "The first octet of the header
> defines the message type and can be one of the following values... The
> type field is followed by a 24 bit length field in big endian form. The
> body of the message follows the length field, and finally a 32 bit CRC
> follows the message body."

The problem is that this *definition* is not sufficient to tell you
what an OS will stick in your memory buffer if you ask to read from
such a file.  You need additional OS-dependent information.

                               -- Adam