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Re: --trace-time times and wireshark timestamps differ

From: Tim Ruehsen <>
Date: Thu, 30 Jun 2016 12:13:05 +0200

On Thursday 30 June 2016 11:00:01 Daniel Stenberg wrote:
> On Thu, 30 Jun 2016, Tim Ruehsen wrote:
> > Just tried curl with '--trace log --trace-time' and capturing the session
> > with wireshark. The times given by curl and the ones given by wireshark
> > differ by ~466ms. I am used to see differences of a few microseconds...
> > but
> > half a second ?
> >
> > Can anyone reproduce that ?
> Never tried it, but curl gets its time stamp from exactly when the
> debug callback is called, which of course may differ from when wireshark
> captures the packet.
> Are you saying they always differ with the same amount (466ms) of time?
> Note that curl shows the "wall clock" number of microseconds, they're not
> relative to the start time. The seconds field is relative to the first
> second it gets logged:

Curl is using CLOCK_MONOTONIC for the milliseconds while wireshark (and all
other tools I know of) use CLOCK_REALTIME. I just changed it in
tool_util.c/tool_tvnow() and now curl and wireshark are in sync and easily


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Received on 2016-06-30