Re: [gentoo-user] Dual OS clock issues

[Mick]

On Thursday 04 Jun 2015 20:30:24 wabenbau@×××××.com wrote:
> Derek Ellison <derek.isname@×××××.com> wrote:
> > I have two HDD in a UEFI system. Windows 8 on one and Gentoo on the
> > other. Currently I have to update the clock everytime I boot to the
> > other OS and I'm wondering if there is a way I can avoid this? It's
> > just starting to get to be a pain to have to update it everytime.
> >
> > Any information would be most welcome.
> >
> > Thanks!
>
> You didn't tell us your timezone and the time difference between
> Windows and Linux. But I assume that you can fix your problem by
> editing /etc/conf.d/hwclock.
>
> --
> Regards
> wabe

Comments in the file pointed to by Wabe say:

# Set CLOCK to "UTC" if your Hardware Clock is set to UTC (also known as
# Greenwich Mean Time).  If that clock is set to the local time, then
# set CLOCK to "local".  Note that if you dual boot with Windows, then
# you should set it to "local".

MSWindows overwrites the hardware clock with the local time on shutdown.  You 
can either define your Gentoo hardware clock as "local" in 
/etc/conf.d/hwclock, so that it is the same with MSWindows ... or set it as 
UTC and fix MSWindows to treat the hardware clock as a UTC setting too.  Add a 
new registry key in MSWindows:

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

-- 
Regards,
Mick