[tz] IANA timezone database - request to add Omaha, Nebraska

Florian Weimer fweimer at redhat.com
Mon Aug 1 08:06:44 UTC 2022

* Paul Eggert:

> On 7/26/22 04:45, Florian Weimer via tz wrote:
>> How does this system implement a programming interface that enumerates
>> the TZ rules?  The typical way is to use readlink to get the IANA
>> identifier, and then use that to look up the rules in the zic input file
>> (because the compiled blobs lack this information).
> It depends on what "TZ rules" means.
> If it means the Rule lines in .zi files, that's not intended for
> end-user consumption. That information is absent from the TZif files 
> output by zic. So I doubt whether you meant that.

There is TzdbZoneRulesCompiler, which I think is used to compile the
data which can be accessed through these interfaces:


There I think ICU has something in this area, too, and the time zone
library that was standardized into C++ has a backend based on .zi files,
too (for systems which do not install the TZif files).

> Distros like FreeBSD should consider installing tzdata.zi as that will
> make it easier for applications to enumerate all supported Zone and
> Link names, as well as do other things.

But that file also lists the (abbreviated) rules, and you wrote above
that those aren't for end-user consumption.


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