On 11/10/15 04:00, Guy Harris wrote:
But if you're stuck with presenting a list of "time zones" from which to select, that might require yet another database. I'm not sure whether that'd be in the scope of the tzdb or the CLDR or neither of them - and for some locations, the appropriate tzdb zone might not really have a good name, other than what it's called now or "XXX time" if it's shuffled between differently named zones or is one of those "XXX time except that we don't do DST" zones.
The basic fact is that tz provides a limited set of generic rules. In hindsight this may have been better identified as a simple numeric ID? That these rules ONLY apply to time data later than 1970 sweeps the problem of identifying just were some places were located earlier than that under the carpet, and some rules needed to describe that history are buried in the backzone file. There is no indication if THAT material is being provided to the client, so even if the 'historic location database' returns a tz identifier for that period there is no indication if the data then provided is actually correct? I totally understand that the historic aspect of all of this is outside the scope of tz and to some extent even outside the remit of tzdist, but the need for a publisher that can be relied on to process the growing volume of normalized historic data is essential? That we can't rely currently on the published data for today is bad enough, but the overall aim should be to provide a single authenticated source for the whole tz system rather than passing the buck ... and I don't rule out that being some alternative publisher? -- Lester Caine - G8HFL ----------------------------- Contact - http://lsces.co.uk/wiki/?page=contact L.S.Caine Electronic Services - http://lsces.co.uk EnquirySolve - http://enquirysolve.com/ Model Engineers Digital Workshop - http://medw.co.uk Rainbow Digital Media - http://rainbowdigitalmedia.co.uk