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Subject: Re: I.1 - System calls - ioctl
From: Peter Zijlstra <a.p.zijlstra@chello.nl>
To: Arnd Bergmann <arnd@arndb.de>
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Date: Mon, 03 Aug 2009 16:22:38 +0200
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On Thu, 2009-07-30 at 19:20 +0200, Arnd Bergmann wrote:
> On Thursday 30 July 2009, stephane eranian wrote:
> > But that won't always work in the case of a 32-bit monitoring tool
> > running on top of
> > a 64-bit OS. Imagine the target id is indeed 64-bit, e.g., inode
> > number (as suggested
> > by Peter). It's not because you are a 32-bit tool than you cannot name
> > a monitoring
> > resource in a 64-bit OS.
> 
> Right, there are obviously things that you cannot address with 
> a 'long', but there are potentially other things that you could
> that you cannot address with an 'int', e.g. an opaque user
> token (representing a user pointer) that you can get back in
> the sample data.
> 
> In the worst case, you could still redefine the argument as a
> transparent union to a long and pointer in the future if you
> use a 'long' now. AFAICT, there are no advantages of using
> an 'int' instead of a 'long', but there are disadvantages of
> using a 'long long'.

OK, so time is running out on this thing. Ingo, Paulus what would you
prefer?