Paul Eggert via tz wrote in <bc9b52dd-5394-4575-9498-69160ee06eb3@cs.ucla.edu>: |On 2026-03-07 01:38, Robert Elz wrote: |> if there are really |> many applications that read TZif files, aside from tzcode | |There are many, including the app I'm writing this email with. I daresay |more apps read TZif via other means than via tzcode and derivatives. It seems to me it uses ICU, and ICU says // Check for TZ_ICU_MAGIC signature at file start. If we get a // signature mismatch, it means we're trying to read a file which // isn't a ICU-modified-zic-created zoneinfo file. Typically this // means the user is passing in a "normal" zoneinfo directory, or // a zoneinfo directory that is polluted with other files, or that // the user passed in the wrong directory. See how https://github.com/unicode-org/icu/blob/main/icu4c/source/tools/tzcode/tz2ic... (cannot be read from Iran or North Korea or even Cuba i think, but that shame aside) "builds transition tables" like grazy. See comments like "why??". They do perform value checks (i was only shortly glancing over). I could imagine they would run to a carefully designed new schematized variant rather sooner than later. (Especially if there would be an easy scheme tester, say libucl of Vsevolod Stakhov, both "well-known to famous": https://github.com/vstakhov/libucl Just my one cent. --steffen | |Der Kragenbaer, The moon bear, |der holt sich munter he cheerfully and one by one |einen nach dem anderen runter wa.ks himself off |(By Robert Gernhardt)