Re: [Qemu-devel] Changing RTC from UTC to local time

[Pavel@Janik.cz (Pavel Janík)]

   From: Bartosz Fabianowski <bartosz@fabianowski.de>
   Date: Sun, 30 May 2004 21:32:26 +0200

This is multi-reply.

   > Attached is a revised patch. With this patch, the default time zone
   > for the RTC is the local time zone of the host. If the command line
   > option "-utc" is specified, the time zone changes to UTC.

I vote against this change. It is nonsense to have local time in UTC
because then when you work on the system that has TZ1 time in BIOS and you
work in TZ2, you can't set your time accordingly, because you must know the
TZ1 vs. TZ2 offset. It *should* be enough to know your own timezone to set
the correct date and time.

On the other hand, I agree that having the possibility to change CMOS time
to local could be handy for those who use broken systems like Microsoft
Windows is.


   From: Flavien <flavien-qemu@lebarbe.net>
   Date: Sun, 30 May 2004 23:59:49 +0200

   > Conclusion : setting RTC to local time is a _broken_ concept.

+1. Also imagine you boot your system in 2:30 the day when time moves back
from 03:00 to 02:00, ie. there are two moments 02:30. Which one it is?


   From: Bartosz Fabianowski <bartosz@fabianowski.de>
   Date: Mon, 31 May 2004 14:11:18 +0200

   > > RTC.  The host OS will provide the correct time as the fake RTC value.
   > 
   > My point exactly. Your host operating system is most likely one you use
   > quite a lot so chances are you will have set it up correctly to take
   > care of DST adjustments.

I often run QEMU on my other system I have in US. I'm in Europe. I do not
want to *always* have bad time... My system in US always gives me right
time now - it is in UTC so it is pretty easy to setup - just say the TZ you
want to have in your host system. I can't imagine how I could do that
should the system use US local time if I want to use Czech local time.

   > b) a safe default that makes all OSes work - which is local time

You still think like Windows only user. Please stop that. This is not safe
default. This would be default that hurts many people, but not Windows
users. This is not "safe".
-- 
Pavel Janík

That's the problem: pretesters aren't finding many more bugs nowadays,
so it'll probably take until 2005 to find and fix enough bugs that we
can comfortably announce the code stable.
                  -- Stefan Monnier in comp.emacs