A NOTE has been added to this issue. ====================================================================== http://austingroupbugs.net/view.php?id=1252 ====================================================================== Reported By: eggert Assigned To: ====================================================================== Project: 1003.1(2016)/Issue7+TC2 Issue ID: 1252 Category: Base Definitions and Headers Type: Enhancement Request Severity: Objection Priority: normal Status: New Name: Paul Eggert Organization: UCLA User Reference: Section: 8.3 Other Environment Variables - TZ Page Number: 180 Line Number: 5945-5946 Interp Status: --- Final Accepted Text: ====================================================================== Date Submitted: 2019-06-02 21:37 UTC Last Modified: 2019-06-28 17:10 UTC ====================================================================== Summary: Extend TZ to allow times outside 00-24 range, permanent DST ====================================================================== Relationships ID Summary ---------------------------------------------------------------------- related to 0001253 clarify that "alternative time&quo... related to 0000661 gramar of TZ variable is insufficient f... ======================================================================
---------------------------------------------------------------------- (0004459) shware_systems (reporter) - 2019-06-28 17:10 http://austingroupbugs.net/view.php?id=1252#c4459 ---------------------------------------------------------------------- If the format is to be extended I would also like to see an additional field that encodes latitudes in HMS format, to seconds precision, so the values are not dependant on being associated with a particular political entity name subject to change, and would differentiate that for a given longitude a country at one latitude may use DST, while another may not, and a third may have DST start and end on different days from the first. There is also that time zone lines can zigzag, so at one latitude it may be GMT-7 and another GMT-6 for the same UTC value. For some time zones an additional longitude field establishing the center of the region using this STD/DST may be desirable also, for cities like Sydney that do DST different from other cities in that nominal hour of timezone. This is more a future direction for the tzdb project to work out, in terms of how much geocoding is actually necessary to fully map current and historic political names, and how to track future changes, but the latitude field is a minimum and I think POSIX could add this as an optional field now. For localtime() one can think of a time zone as a 15 degree wide slice of the globe, as a simplifying presumption, but this is not the standard reflecting reality of how time zones are actually defined. Their interpretation is location dependant and a location on a globe has both longitude and latitude, not longitude alone. Issue History Date Modified Username Field Change ====================================================================== 2019-06-02 21:37 eggert New Issue 2019-06-02 21:37 eggert Name => Paul Eggert 2019-06-02 21:37 eggert Organization => UCLA 2019-06-02 21:37 eggert Section => 8.3 Other Environment Variables - TZ 2019-06-02 21:37 eggert Page Number => unknown; don't have PDF 2019-06-02 21:37 eggert Line Number => unknown; don't have PDF 2019-06-02 21:56 Don Cragun Relationship added related to 0000661 2019-06-02 22:12 Don Cragun Page Number unknown; don't have PDF => 180 2019-06-02 22:12 Don Cragun Line Number unknown; don't have PDF => 5945-5946 2019-06-02 22:12 Don Cragun Interp Status => --- 2019-06-28 14:28 geoffclare Note Added: 0004458 2019-06-28 14:29 geoffclare Relationship added related to 0001253 2019-06-28 17:10 shware_systems Note Added: 0004459 ======================================================================
