BST and Europe timezone configuration

[XelaParis]

Hi,

I have a question regarding how timezones are working.
Indeed, if I configure "TZ=BST", I get:
sh-3.2$ date
Fri May 13 07:43:39 BST 2011

And when I configure "TZ=Europe/London", I get:
sh-3.2$ date
Fri May 13 08:43:20 BST 2011

There is no BST file in /usr/share/zoneinfo, so I am asking how it is managed for BST settings and why it is different from setting Europe/London.

thanks in advance

Alex

[Rubberman]

I think it is because one is daylight saving time enabled (Europe/London), but the raw BST (British Standard Time) is not? That's all I can figure out. I get the same results you do on my SL6 (RHEL6) system, but since we (in Chicago) are on US CDT (Central Daylight Time), the proper offset from London should be 6 hours, which the TZ=Europe/London setting gives. Setting TZ=GMT, the offset is 5 hours, which computes with the daylight saving time setting (1 hour later than standard time).

[impert]

Is it because "BST" simply isn't recognised, so date defaults to giving system time, ie UT (GMT)?
That's my best guess.

[Rubberman]

Is it because "BST" simply isn't recognised, so date defaults to giving system time, ie UT (GMT)?
That's my best guess.

That's a likely scenario, assuming their RTC is set using GMT. Usually that's the case, but not necessarily.