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Date: Tue, 29 Aug 2006 09:15:33 -0400
From: Theodore Tso <tytso@mit.edu>
To: linux@horizon.com
Cc: johnstul@us.ibm.com, zippel@linux-m68k.org, linux-kernel@vger.kernel.org,
       theotso@us.ibm.com
Subject: Re: Linux time code
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On Mon, Aug 28, 2006 at 11:28:29PM -0400, linux@horizon.com wrote:
> > While its possible to smooth out the leapsecond (which would be useful
> > to many folks), the problem is one's system would then diverge from UTC
> > for that leapsecond. 
> 
> The Posix-mandated behaviour *requires* diverging from UTC for some
> time period around the leap second.  All you can do is decide how
> to schedule the divergence.

POSIX mandates this for gettimeofday() and CLOCK_REALTIME.  

However, a conforming implementation, could (either in userspace or in
the kernel) provide access to other time bases, include TAI or the
proposed UTS time scales.

						- Ted
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