FW: Europe/Paris timezone bug

Rodrigo Severo rodrigo.lists at fabricadeideias.com
Thu Oct 30 14:47:13 UTC 2003


I am not sure I understood your problem but let me try to help you.

>There appears to be a bug in the timezone libraries(i've tested against 
>localtime.c	7.76) when dealing with Daylight Saving Time and the France 
>timezone. Daylight saving goes into effect at 3:00am instead of 2:00am. 
>Below I have attached simple test case.
I am not sure why do you think Daylight saving should end its effect at 
2:00am localtime instead of 3:00am localtime as it's currently defined 
in the zoneinfo file but AFAICS, it's not a library bug, it might be a 
zoneinfo definition bug:

Rule    EU      1996    max     -       Oct     lastSun  1:00u  0       -

The above rule states that the daylight saving ends at the last sunday 
of october 1:00 UTC time.

The Europe/Paris zone defines that Paris is one hour ahead of UTC 
outside daylight saving time, or 2 hours during daylight saving time so 
only at 3:00 local time (which is 1:00 UTC time) the daylight saving 
should end. Which is what is happening, isn't it?

As far as as can understand, there is no library bug. There might be a 
zoneinfo bug if this (daylight saving ending only at 3:00am localtime) 
isn't what should happen.


Rodrigo Severo

>This is the output of the test I ran on both Mac(10.2.8) and PalmSim
>bash-2.05a$ TZ="Europe/Paris" ./a.out
>when = 0x3f9b0e44 is_dst = 1 zone = CEST Sun Oct 26 01:59:00 2003 when =
>0x3f9b0e80 is_dst = 1 zone = CEST Sun Oct 26 02:00:00 2003 when = 0x3f9b11c8
>is_dst = 1 zone = CEST Sun Oct 26 02:14:00 2003 when = 0x3f9b2014 is_dst = 0
>zone = CET Sun Oct 26 02:15:00 2003
>You will notice that the difference between 02:14:00 and 02:15:00 is 3660 
>which is 61 minutes. If you set the device to 2:14 and wait 46 minutes it 
>will change the time back to 02:00.
>There should be no difference in setting the time to 02:00, 02:14, or 
>02:15 since anytime after 02:00 should fall outside of Daylight Saving 
>Time on this date.

Rodrigo Severo
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