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Subject: Re: [PATCH] [RFC] notify userspace about time changes
From: john stultz <johnstul@us.ibm.com>
To: Chris Friesen <chris.friesen@genband.com>
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Date: Wed, 04 Aug 2010 17:52:26 -0700
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On Wed, 2010-08-04 at 12:48 -0600, Chris Friesen wrote:
> On 08/04/2010 09:58 AM, john stultz wrote:
> 
> > Is there a actual use case that you need this for?  I don't really have
> > an issue with the code I just really want to make sure the feature would
> > be useful enough to justify the API and code maintenance going forward.
> 
> We actually added a time-change-notification mechanism internally a long
> time ago but never saw demand for it and so never bothered trying to
> push it upstream.  Ours is signal-based.
> 
> Among other things we use it to pass on time-change notifications to an
> emulator running a proprietary OS that really cares about having an
> accurate time-of-day but can't afford a syscall to retrieve it every time.

So the eventfd based method (and the filtering) proposed would work for
you? 

thanks
-john


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