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Re: differences between hwclock <-> date due to time zone issues? ...

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On Fri 24 Mar 2023 at 19:10:49 (-0400), Stefan Monnier wrote:
> > That works great for the Live OS, but not for the fixed-disk OS.  If
> > the Live OS sets the HW clock to local upon shutdown, but the fixed-disk
> > OS expects the HW clock to be UTC, then the fixed-disk OS is wrong
> > every time it boots after the Live OS.
> 
> AFAIK the Linux kernel is pretty careful not to change the *hour* of the
> hwclock: when using NTP, it will tweak the seconds to keep the hwclock
> in sync with the rest of the world, but leave the hours alone, so as to
> preserve the timezone in use, regardless if it's the right one (UTC) or
> something else.

Minutes, rather than hours, I would have thought. After all, there are
some crazy TZs out there, and even crazier daylight savings schemes.

> I assume GNU/Linux distributions like Debian are similarly careful,
> since dual booting with a Windows install that doesn't use UTC for the
> hwclock was a very common use case at least some years ago.

Cheers,
David.

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Thread

differences between hwclock <-> date due to time zone issues? ... Albretch Mueller <lbrtchx@gmail.com> - 2023-03-23 22:50 +0100
  Re: differences between hwclock <-> date due to time zone issues? ... Stefan Monnier <monnier@iro.umontreal.ca> - 2023-03-23 23:10 +0100
  Re: differences between hwclock <-> date due to time zone issues? ... Cindy Sue Causey <butterflybytes@gmail.com> - 2023-03-23 23:10 +0100
    Re: differences between hwclock <-> date due to time zone issues? ... Cindy Sue Causey <butterflybytes@gmail.com> - 2023-03-23 23:30 +0100
  Re: differences between hwclock <-> date due to time zone issues? ... David Wright <deblis@lionunicorn.co.uk> - 2023-03-23 23:50 +0100
  Re: differences between hwclock <-> date due to time zone issues? ... Andy Smith <andy@strugglers.net> - 2023-03-24 15:50 +0100
    Re: differences between hwclock <-> date due to time zone issues? ... Albretch Mueller <lbrtchx@gmail.com> - 2023-03-24 18:20 +0100
      Re: differences between hwclock <-> date due to time zone issues? ... Greg Wooledge <greg@wooledge.org> - 2023-03-24 22:50 +0100
        Re: differences between hwclock <-> date due to time zone issues? ... Stefan Monnier <monnier@iro.umontreal.ca> - 2023-03-24 23:00 +0100
          Re: differences between hwclock <-> date due to time zone issues? ... Greg Wooledge <greg@wooledge.org> - 2023-03-24 23:10 +0100
            Re: differences between hwclock <-> date due to time zone issues? ... Stefan Monnier <monnier@iro.umontreal.ca> - 2023-03-25 00:20 +0100
              Re: differences between hwclock <-> date due to time zone issues? ... Albretch Mueller <lbrtchx@gmail.com> - 2023-03-25 01:10 +0100
                Re: differences between hwclock <-> date due to time zone issues? ... Max Nikulin <manikulin@gmail.com> - 2023-03-25 04:20 +0100
                Re: differences between hwclock <-> date due to time zone issues? ... Albretch Mueller <lbrtchx@gmail.com> - 2023-03-25 04:50 +0100
                Re: differences between hwclock <-> date due to time zone issues? ... Max Nikulin <manikulin@gmail.com> - 2023-03-25 06:00 +0100
                Re: differences between hwclock <-> date due to time zone issues? ... Max Nikulin <manikulin@gmail.com> - 2023-03-25 09:00 +0100
              Re: differences between hwclock <-> date due to time zone issues? ... David Wright <deblis@lionunicorn.co.uk> - 2023-03-25 05:30 +0100
      Re: differences between hwclock <-> date due to time zone issues? ... David Wright <deblis@lionunicorn.co.uk> - 2023-03-25 05:30 +0100
        Re: differences between hwclock <-> date due to time zone issues? ... Felix Miata <mrmazda@earthlink.net> - 2023-03-25 05:50 +0100

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