[ntp:questions] ntpq -crv gives results in local time, not UTC

Gom gom at gom.invalid
Fri Apr 6 10:19:19 UTC 2012

> I agree that my solution is fraught with cost and can imagine others
> reaching different decisions.  I would much prefer if Windows were
> clever enough to use the UTC offset in effect at the given time when
> converting between UTC and local -- instead, it always uses the
> current UTC offset essentially pretending daylight savings doesn't
> exist.  Worse, applications can't work around it without rewriting the
> bulk of Windows UTC/localtime conversion code, either relying on the
> undocumented Windows timezone information in the registry, or using
> the open source Olsen stuff and taking on keeping it up to date.


I'm not sure sure I understand what you are meaning.
You state Windows (the OS) doesn't manage correctly the conversion from 
local to UTC, but when does the OS do that ? Isn't this more of a 
software issue ?

So yes, if you use C or Win32 librairies, mapping Local to UTC can be a 
pain, specifically with the DST settings. There is no easy time mapping 

But with .Net, there is since the 3.5 release the TimeZoneInfo class 
that will do automatically all the mappings you want. See

So there are tools to do good time mappings, but they are not available 
under basic C.

Or maybe didn't I understand what you meant by "Windows misrepresents 
historical or future timestamps" ??


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