Re: [Tzdist] [tzdist] #34 (service): should we include a raw tzdb format media type?

[Tim Parenti <[e-mail]>]

On 8 January 2015 at 11:12, Paul Eggert <[e-mail]> wrote:

> Lester Caine wrote:
>
>> I'm not sure if each TZid has it's own full
>> expansion from the base generic rules? Is that the case Paul?
>>
>
> Yes and no.  There are separate files for America/Los_Angeles,
> Europe/Paris, etc.  But there are merely links for aliases.


To expound a bit here, with the exception of links for aliases, TZ binary
files can stand on their own and are not dependent on one another.  The
encoding for each file contains each individual transition point for that
zone, what we would probably call an "expansion" in tzdist parlance.  Once
compiled down to the binaries, there is no notion of zones sharing rules.

On 8 January 2015 at 11:52, Lester Caine <[e-mail]> wrote:

> But there will be separate files for many aliases which are now all
> following the same generic rule - even after the cull for 1970 cut-off,
> some files still have pre-1970 only differences? Which would be
> different again with a later truncation point?
>

I think the truncation discussion is strictly orthogonal to this issue.

That said, if a user requests a TZ binary file for a zone identifier which
is simply an alias, such as US/Eastern, I think it would be perfectly
reasonable for the server to return the corresponding file for the linked
zone — in this case, America/New_York.  Whether the response should also
include some note about the "canonical" zone name, I'm not sure.

--
Tim Parenti