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Date: Mon, 12 Feb 2007 09:19:39 -0600
From: Brian Ford <Brian DOT Ford AT FlightSafety DOT com>
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To: cygwin AT cygwin DOT com
Subject: Re: strange bug in gettimeofday function
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On Mon, 12 Feb 2007, Carlo Florendo wrote:

> Windows could be accurate up to 15 ms or perhaps a little bit more.
> However, it is very difficult to achieve less than 15 ms or microsecond
> accuracy with windows due to the limitation on the OS itself.  Our
> extensive tests on windows clocks and timers reveal that windows cannot
> be accurate to the microsecond level or below 15 ms.
>
> In any case, in my experience, windows cannot be accurate with a
> precision of up to 15 milliseconds.

I'm sorry, could you repeat that value one more time, just in case someone
missed it ;-).

Anyway, I don't think it is relevant to the original thread's question,
but I can assure you that Windows can be used for accurate timings in down
to 1 or 2 ms (depending on the OS version).

I'm not exactly sure what your definition of accurate is.  And, for the
OP, I haven't ever seen this behavior from gettimeofday.

-- 
Brian Ford
Lead Realtime Software Engineer
VITAL - Visual Simulation Systems
FlightSafety International
the best safety device in any aircraft is a well-trained crew...

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