[ntp:questions] Automatic time synchronization of local hw clock.

Martin Burnicki martin.burnicki at meinberg.de
Tue Apr 22 09:44:52 UTC 2014

David Taylor wrote:
> On 16/04/2014 14:50, Martin Burnicki wrote:
> []
>> However, when the NTP service is shut down then it stops disciplining
>> the system time anyway and thus calls the Windows API which sets the
>> time with the current time as new time. This should force Windows to
>> update the time in the RTC chip.
> []
>> Martin
> I understood that it was when Windows shut down that NTP set the RTC
> chip, not when the service was shut down.  I've not looked at the code
> (I wouldn't know where to start) to confirm this one way or the other,
> though.

Indeed this seems to have changed in 4.2.6 and current ntp-dev. The 
Windows port of ntpd now only sets the system time if it was 
synchronized before, and if it is shutdown because the whole system is 

The code is still in current current ntp-dev, in nt_clockstuff.c around 
line 850.

(David, sorry for the personal reply I sent accidentally before)

Martin Burnicki

Meinberg Funkuhren
Bad Pyrmont

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