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[ts-7000] Re: Endianess Problem

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Subject: [ts-7000] Re: Endianess Problem
From: "Adriano Naspolini" <>
Date: Tue, 24 Mar 2009 23:20:23 -0000
Hi people,

Problem "solved". Lenny/armel is little endian. I made the test with native 
compiler and it works.


Adriano




--- In  David Hawkins <> wrote:
>
> Hi Adriano,
> 
> >> Maybe you didn't notice that the number is not little-endian nor 
> >> big-endian, but middle-endian.
> 
> Ah, I'm sorry, I did not notice that.
> 
> >> It means that it's little-endian in bytes, but big-endian in words. (see 
> >> http://en.wikipedia.org/wiki/Endianness#Middle-endian)
> >>
> >> Maybe a middleware solve the problem (introducing a little overhead) and 
> >> lots of work (i never used), but before, I'll try to upgrade the kernel to 
> >> armel (as i read, it's little-endian).
> 
> Middleware, such as the ACE C++ library I use, would expect the
> doubles to be in big or little endian ordering, not middle
> endian.
> 
> >> Now, the question is: why, the hell, arm has this "stupid" representation? 
> >> :)
> > 
> > Probably because the core is 32-bit little-endian.  Anything larger than
> > that is synthetic, and subject to someone writing crappy, nonportable
> > code to implement it.  Of course, you can always fsck it up with smaller
> > word sizes too.
> > 
> > ARM machines can be either big-endian or little-endian, but they usually
> > aren't dynamically configurable the way some MIPS machines are.  "ARM"
> > vs. "ARMEL" is mostly about parameter passing conventions, I don't think
> > it's likely to address your problem.
> 
> That sounds like the most likely reason.
> 
> On the bright-side, I think it means that you can use htonl() on
> both halves, and put the 8-bytes back into little-endian order :)
> 
> It would be worth your while discovering where this weirdness
> comes from, eg. write a small piece of code and disassemble it
> to see what library calls are used.
> 
> Cheers,
> Dave
>




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