[tz] bug in export TZ where day light savings spans Dec 31st?
abbotti at mev.co.uk
Tue Jun 5 09:03:57 UTC 2012
On 04/06/12 21:39, david singleton wrote:
> When I use the example from the timezone man page to define, and export
> a local TZ variable:
> export TZ="NZST-12.00:00NZDT-13:00:00,M10.1.0,M3.3.0"
> And then set the date to December 31st at 23:59 I see the clock roll over to 00:00
> But when I define a timezone using a positive offset I see time get
> set backwards at December 31st. I believe time should not get set back
> on December 31st for any timezones whose day light savings span December 31st.
> export TZ="NZST+12.00:00NZDT+13:00:00,M10.1.0,M3.3.0"
> date 123123592011.55
> Sat Dec 31 23:59:55 2011
I just tried this and I got
Sat Dec 31 23:59:55 NZST 2011
> when I wait 5 seconds and check the date again I see the date has been
> adjusted to Dec 31st at 12:00?
> root at dstest2:~# date
> Sat Dec 31 12:00:01 NZST 2011
I waited about 9 seconds and got
Sun Jan 1 00:00:04 NZST 2012
> What is happening with TZs defined with a positive offset?
> I can reproduce this on Linux systems using glibc 2.5.90 up through glibc 2.12.1.
> I was hoping you could help me understand what is going on?
I couldn't reproduce your problem, but I notice your first output was
missing the timezone abbreviation, so it was defaulting to UTC when
setting the time. I don't know why it would do that, but I was using a
later GNU glibc 2.15(.something) and the 'date' command from GNU
-=( Ian Abbott @ MEV Ltd. E-mail: <abbotti at mev.co.uk> )=-
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