On 8/1/22 01:35, Florian Weimer wrote:
* Paul Eggert:
Looking back at your original question "How does this system implement a programming interface that enumerates the TZ rules?" <https://mm.icann.org/pipermail/tz/2022-July/031702.html> I think the answer is that TZif files don't do that....
But that means the software has to obtain the IANA time zone name (which is not part of the TZif data, either), and that exposes the allegedly invisible, internal identifier across an interface boundary.
Sure, names like America/Los_Angeles are visible across an operating system's internal interfaces, but those interfaces need not be exposed to the end user. By the way, earlier I thought that you were asking about Rule names like "US" and "Canada" but I see now that you're asking about Zone names like "America/Los_Angeles" and Link names like "US/Pacific". Rule names are internal to TZDB, and I hope downstream users aren't relying on them staying the same from one release to the next, or even within a single release (as the Rule names in tzdata.zi differ from those in 'northamerica'). Another way to put this is that Zone and Link names are covered by the interface stability guidelines[1]; Rule names are not. [1] https://data.iana.org/time-zones/theory.html#stability