[tz] Are these valid timezone definitions?

Tadashi Abe tdsh.abe at gmail.com
Thu Jun 14 16:06:41 UTC 2012

Hi, sorry to interrupt with newbie question.

david singleton wrote:
>When I define a timezone with  export
>there is no change in time when daylight savings ends.
>Is this a known problem?  Or a problem with how the timezones are defined?

Now I'm testing DST start/end by setting the actual system clock
as same as the above method and get the same issue.

1. export TZ="NZST-12:00:00NZDT-13:00:00,M10.1.0,M3.3.0"
2. set system clock just 5 seconds prior to DST [start|end]
3. 5 seconds later, check if switch between DST and STD occurs, but not.

As the comment from Zefram, it works when I check date with -d option.

>It's always difficult to test timezone offset issues when you're
>stating the test times in local time.  By the way, your testing method
>of modifying the system clock is problematic.  It's much better to use
>the -d option of GNU date to display a particular time without touching
>the clock.

Why doesn't it work well when I try to test by modifying the actual
system clock?

Tadashi Abe

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