[OpenIndiana-discuss] Daylight saving time - again

[Jim Klimov]

On 2013-10-27 17:13, Jean-Pierre André wrote:
> On a computer which boots on OpenIndiana and Windows, I have to
> obey the Windows requirement for the hardware clock to be set on
> local time.

Are you ready for the correct answer? ;)
For at least the past dozen years, maybe more, Windows does not
actually require that. There is a semi-documented registry flag
for it to keep the HWclock in UTC and convert to local time as
needed. Quoting from a blog post I copied long ago (alas, got
no origin reference):

---
The registry tweak that will tell Windows to interpret the hardware
clock as UTC time:




Windows Registry Editor Version 5.00

[HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Control\TimeZoneInformation]
"RealTimeIsUniversal"=dword:00000001





It would seem that there are still some issues with this:
http://blogs.msdn.com/oldnewthing/archive/2004/09/02/224672.aspx

It seems to work most of the "time" for me but 1 or twice a day the
clock changes to the timezone offset again. I just have to do a
   w32tm /resync /nowait
or (in domain/NTP setup)
   net time /set
to fix it. My suspicion is that the clock applet in the tray is
monkeying it up.
---

I myself saw no problems on numerous desktops and servers, but YMMV :)

HTH,
Jim