bug#11807: (Windows XP issue?) Re: bug#11807: M-x display-time-world & EDT/DST

[Jambunathan K <kjambunathan@gmail.com>]

Jason Rumney <jasonr@gnu.org> writes:

> Eli Zaretskii <eliz@gnu.org> writes:
>
>> I don't think the MS-Windows version of tzset supports TZ values such
>> as CET-1CEST.  The time-zone strings it supports need to be 3-letter,
>> not 4-letter.  See this thread for more:
>
> That may be an issue for that particular timezone string, but I think
> the issue is deeper than that. From my recollection, Windows always
> applies the timezone rules configured in the system control panel,
> it only partially supports TZ environment variables for overriding
> those.  More precisely, Windows itself does not support the TZ variable
> at all, the C runtime library does, but retains calls into the Windows
> system library for information that is missing from the TZ variable such
> as DST start/end dates (which do not exist for K Jambunathan's locale,
> so DST is never applied on his machine).

Till such time as a right fix is found, the command has to be either
selectively disabled or a warning issued to the user saying that some
sort of DST adjustment might have to be made by the user himself.

Having a command report incorrect values is not a good idea.