comp.lang.ada
 help / color / mirror / Atom feed
From: "Dr. Michael Paus" <paus@ib-paus.com>
Subject: Re: Last stream problem: byte order
Date: Wed, 27 Mar 2002 19:12:58 +0100
Date: 2002-03-27T18:12:59+00:00	[thread overview]
Message-ID: <3CA20BAA.FD53C08A@ib-paus.com> (raw)
In-Reply-To: mailman.1017243242.6790.comp.lang.ada@ada.eu.org

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



  reply	other threads:[~2002-03-27 18:12 UTC|newest]

Thread overview: 16+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2002-03-25 19:45 Last stream problem: byte order Erik Sigra
2002-03-25 22:28 ` Jeffrey Carter
2002-03-25 22:36 ` Stephen Leake
2002-03-26  4:32 ` Eric G. Miller
2002-03-26 10:25 ` Dr. Michael Paus
2002-03-26 17:53   ` Pascal Obry
2002-03-26 18:25     ` Dr. Michael Paus
2002-03-26 19:25       ` Pascal Obry
2002-03-27 15:37   ` Erik Sigra
2002-03-27 18:12     ` Dr. Michael Paus [this message]
2002-03-28  2:24       ` Eric G. Miller
2002-03-28 18:34         ` Stephen Leake
2002-03-28 18:38         ` Simon Wright
2002-03-29  2:08           ` Eric G. Miller
2002-03-29  6:52             ` Simon Wright
2002-03-29  7:06               ` Simon Wright
replies disabled

This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox