Some questions about the database format

Yves Goergen nospam.list at
Thu Jul 1 15:23:37 UTC 2010

On 29.06.2010 16:11 CE(S)T, yoshito_umaoka at wrote:
> These are well defined in the man page of zic.
> Download tzcodeC.tar.gz (C is a version such as 2010j) from 
> and read docs included in the distribution.

Thank you. That's indeed a very complete definition of the files. I just
didn't see it at first.

> Strictly speaking, you cannot expect DST start and end are always paired 
> within a single year. Also, some rules used by the tzdatabasemight not be 
> directly mapped to Windows/.NET style rule.

I see. I have already found definitions of double daylight saving times
and other weird stuff. So I've dropped my hope to use TimeZoneInfo and
am now going to use custom data structures and algorithms to use the
data. (See other thread.)

Yves Goergen "LonelyPixel" <nospam.list at>
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