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Message-ID: <3C4F64B4.380E84AF@lapo.it>
Date: Thu, 24 Jan 2002 02:34:44 +0100
From: Lapo Luchini <lapo AT lapo DOT it>
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To: cygwin AT cygwin DOT com
Subject: Re: gettimeofday() does not returns usec resolution
References: <00af01c1a3de$7af04b40$60a407d5 AT BRAMSCHE> <3C4E6FD1 DOT 9060505 AT computer DOT org> <20020123172718 DOT GE6765 AT redhat DOT com> <3C4F01DF DOT 70AA4F00 AT lapo DOT it> <20020123190335 DOT GC18042 AT redhat DOT com>
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> Hmm.  I do remember this patch.  Can you submit this to cygwin-patches
> in the correct format: http://cygwin.com/contrib.html ?

Given enough time, yes (never hacked that one, but it seems that only
winsup/cygwin/times.cc would need to be modified).. anyway of course I'm one of
the few that actually would like to have this feature so I guess there's no big
hurry.

Of course the number reported by PerformanceTimer has an unknown offset with
system time (it appears to start at 0 at program start, but that's not clearly
specified) so I would have calculate an initial "offset" in the "old" way... this
would give 3-4 microsecond precision on "deltas" but an initial uncertainty of
the usual 15 milliseconds or so.

I guess that it's better that having that uncertainty between ANY two
measurations... but if someone has some other idea.. please suggest =)

> Do you have an assignment on file with Red Hat?

Sorry but english knowledge doesn't let me understand "assignment on file", could
you explain it to me with other words?

> >-------
> >int gettimeofday(struct timeval *tv, struct timezone *tz)
> >{....
> >}
> >------------

A note for everyone: that implementation was taken from tim Prince's message on
lmbench and of course lacked any syncronization with real time as was used only
for deltas.

--
Lapo 'Raist' Luchini
lapo AT lapo DOT it (PGP & X.509 keys available)
http://www.lapo.it (ICQ UIN: 529796)


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