[tz] On merging timezones - a radical proposal.

Petr Machata pmachata at redhat.com
Thu May 23 12:28:01 UTC 2013

"Jonathan M Davis" <jmdavisProg at gmx.com> writes:

> On Wednesday, May 22, 2013 12:24:39 Guy Harris wrote:
>> > We already don't handle (to make up an arbitrary example) people
>> > who moved from New York to Phoenix in 1992, but spent a month-long
>> > vacation in Florida in 2004.
>> We don't handle that because UN*X APIs don't offer a mechanism for
>> saying "please use the time zone I was in at a given time to convert
>> that time"; if they did, they could use our database for that.
> D's standard library can do that sort of thing, but it's forced to
> read the files directly (and Boost has something similar, though IIRC,
> they maintain the TZ information in a different format rather than
> using the system's TZ files).  The *nix C API is definitely limited

Boost uses CSV with current offset and rules that look similar to what's
in POSIX TZ string.  It doesn't nearly capture the whole of zoneinfo.
If that's what you mean.

And, BTW, how does D do it?  Does it record the current TZ with the
mtime or some such?  It seems this would need some sort of log recording
where the user was when.


More information about the tz mailing list