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From: "Dr. Michael Paus" <paus@ib-paus.com>
Newsgroups: comp.lang.ada
Subject: Re: Last stream problem: byte order
Date: Wed, 27 Mar 2002 19:12:58 +0100
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Erik Sigra schrieb:
> 
> tisdagen den 26 mars 2002 11.25 skrev du:
> > If you also check the byte order of your system at runtime (there is a
> > system constant in Ada which you can check) you can even achieve the effect
> > that all stream data is always written in network byte order independent of
> > the platform your program is running on.
> 
> Why runtime check? Compile time check seems more reasonable to me. Or can the
> same compiled program really run on architectures with different endiannes?

It depends on how clever the compiler is. If the compiler optimizes the
static expression in the following if-statement away then it is indeed a
compile time check. Otherwise it is a run-time check.

      if System.Default_Bit_Order = System.Low_Order_First then
         ... (swap the bytes)
      else
         ... (don't swap the bytes)
      end if;

But I don't think this makes a big difference in either case.

Michael