diff options
| author | Philip Paeps <philip@FreeBSD.org> | 2026-09-12 00:25:12 +0000 |
|---|---|---|
| committer | Philip Paeps <philip@FreeBSD.org> | 2026-09-12 00:25:12 +0000 |
| commit | ef5bc5a1160e88267d14afed1df321cf4d5c35f9 (patch) | |
| tree | c27ce91c1355e78e97f9b9b725c468a95f04a97a | |
| parent | dd6fd39608b6197e67fba90d4e1deb15f70b8a4f (diff) | |
Import tzdata 2026dvendor/tzdata/tzdata2026dvendor/tzdata
| -rw-r--r-- | CONTRIBUTING | 2 | ||||
| -rw-r--r-- | Makefile | 19 | ||||
| -rw-r--r-- | NEWS | 115 | ||||
| -rw-r--r-- | README | 2 | ||||
| -rw-r--r-- | asia | 24 | ||||
| -rw-r--r-- | backward | 54 | ||||
| -rw-r--r-- | backzone | 11 | ||||
| -rw-r--r-- | northamerica | 126 | ||||
| -rw-r--r-- | southamerica | 29 | ||||
| -rw-r--r-- | theory.html | 63 | ||||
| -rw-r--r-- | version | 2 | ||||
| -rw-r--r-- | zone.tab | 2 | ||||
| -rw-r--r-- | zone1970.tab | 2 | ||||
| -rw-r--r-- | zonenow.tab | 4 |
14 files changed, 332 insertions, 123 deletions
diff --git a/CONTRIBUTING b/CONTRIBUTING index c5fa803f7275..213ae67e962a 100644 --- a/CONTRIBUTING +++ b/CONTRIBUTING @@ -22,7 +22,7 @@ To email small changes, please run a POSIX shell command like For more-elaborate or possibly controversial changes, such as renaming, adding or removing zones, please read “Theory and pragmatics of the tz code and data” -<https://www.iana.org/time-zones/repository/theory.html>. +<https://data.iana.org/time-zones/theory.html> It is also good to browse the mailing list archives <https://lists.iana.org/hyperkitty/list/tz@iana.org/> for examples of patches that tend to work well. @@ -172,9 +172,9 @@ EXPIRES_LINE= 0 TZDATA_TEXT= leapseconds tzdata.zi -# For backward-compatibility links for old zone names, use +# For backward-compatibility links and zones for old names, use # BACKWARD= backward -# To omit these links, use +# To omit these links and zones, use # BACKWARD= BACKWARD= backward @@ -574,7 +574,7 @@ SAFE_CHAR= '[]'$(SAFE_CHARSET)'-]' # These non-alphabetic, non-ASCII printable characters are # used in commentary or in generated *.txt files # and are not likely to cause confusion. -UNUSUAL_OK_CHARSET= §«°±»½¾×–‘’“”•→−≤★⟨⟩⯪ +UNUSUAL_OK_CHARSET= §«°±»½¾¿×–‘’“”•→−≤★⟨⟩⯪ # Put this in a bracket expression to match spaces. s = [:space:] @@ -922,7 +922,7 @@ check_mild: check_web check_zishrink \ UTF8_LOCALE_MISSING = \ { test ! '$(UTF8_LOCALE)' \ || ! printf 'A\304\200B\n' \ - | LC_ALL='$(UTF8_LOCALE)' grep -q '^A.B$$' >/dev/null 2>&1 \ + | LC_ALL='$(UTF8_LOCALE)' grep -q '^A[[:alpha:]]B$$' >/dev/null 2>&1 \ || { export LC_ALL='$(UTF8_LOCALE)'; false; }; } character-set.ck: $(ENCHILADA) @@ -1006,11 +1006,11 @@ now.ck: checknow.awk date tzdata.zi zdump zic zone1970.tab zonenow.tab now=$(CHECK_NOW_TIMESTAMP) && \ future=$$(($(CHECK_NOW_FUTURE_SECS) + $$now)) && \ ./zdump -i -t $$now,$$future \ - $$(find "$$PWD/$@d"/????*/ -type f) \ + $$(find "$$PWD/$@d"/????*/ -type f -o -type l) \ >$@d/zdump-now.tab && \ ./zdump -i -t 0,$$future \ $$(find "$$PWD/$@d" -name Etc -prune \ - -o -type f ! -name '*.tab' -print) \ + -o \( -type f -o -type l \) ! -name '*.tab' -print) \ >$@d/zdump-1970.tab && \ $(AWK) \ -v now=$$now \ @@ -1018,7 +1018,12 @@ now.ck: checknow.awk date tzdata.zi zdump zic zone1970.tab zonenow.tab -v zdump_table=$@d/zdump-now.tab \ -f checknow.awk zonenow.tab $(AWK) \ - 'BEGIN {print "-\t-\tUTC"} /^Zone/ {print "-\t-\t" $$2}' \ + 'BEGIN { \ + SysVzone["EST5EDT"] = 1; SysVzone["CST6CDT"] = 1; \ + SysVzone["MST7MDT"] = 1; SysVzone["PST8PDT"] = 1; \ + print "-\t-\tUTC" \ + } \ + $$1 == "Zone" && !SysVzone[$$2] {print "-\t-\t" $$2}' \ $(PRIMARY_YDATA) backward factory | \ $(AWK) \ -v zdump_table=$@d/zdump-1970.tab \ @@ -1,5 +1,87 @@ News for the tz database +Release 2026d - 2026-09-11 15:21:07 -0700 + + Briefly: + Canada’s Northwest Territories moved to permanent -06 on 2026-08-21. + Obsolescent settings like TZ="EST5EDT" now conform better to POSIX. + Fix security, performance and porting bugs in zic and localtime. + + Changes to future timestamps + + Canada’s Northwest Territories will not fall back on 2026-11-01 + and will stay on -06 year-round, matching Alberta’s recent change. + Model this with its traditional abbreviation CST. Although the + change to permanent -06 legally took place on 2026-08-21, + temporarily model the change to occur on 2026-11-01 at 02:00 + for the same reason as other recent temporary hacks. (Caution: + see “NOTE FOR 2026b TEMPORARY HACK FOR CLDR AND CANADA” below.) + This affects only America/Inuvik as the rest of the territory is + covered by America/Edmonton, for which the equivalent change was + released in 2026c. + + Changes to past timestamps + + Colombia’s 1992-05-02 spring forward was at 00:00, not 24:00. + + Iran’s 1979-05-26 spring forward was at 00:00, not 24:00. + (Thanks to N.F. Hase.) + + The backward-compatibility names EST5EDT, CST6CDT, MST7MDT, and + PST8PDT now conform better to POSIX. For example, EST5EDT now + always uses the abbreviation "EST" for standard time (now always 5 + hours behind UT) and "EDT" for daylight saving time, whereas it + formerly had different UT offsets before standard time was + introduced and sometimes used abbreviations like "LMT", "EWT" and + "EPT", all contrary to POSIX. Also, though not required by POSIX + these names now use US federal rules rather than rules of places + like New York, reverting to 2024a behavior. This change affects + only timestamps before 1966-10-30 at 01:00 standard time. + + Other data changes + + The temporary hacks used for North American timekeeping changes + now work around a libstdc++ std::chrono bug in GCC 14.1-14.4, + 15.1-15.2, and 16.1; see GCC bug 124851. This data change does + not affect TZif files or timestamps. The change does not work + around the related but less serious GCC bugs 116110 and 124513. + These GCC bugs are all fixed in GCC 16.2. + + Changes to code + + zic now rejects Link targets that would have invalid names, and + more efficiently processes Expires, Leap and Rule lines with years + far in the past or future. (Thanks to Darren Carreras.) + + zic now ports to systems that report lack of link support via + EINVAL, ENOSYS or EPERM errno values. (Thanks to Tom Lane.) + + When tzset and related functions encounter a TZif file that is too + large for them, they now consistently fail instead of sometimes + silently ignoring excess parts of the file. + + localtime-related functions no longer mishandle extreme timestamps + when given TZif files holding some unlikely timezone histories. + (Problem reported by David Sarkisyan.) + + localtime-related functions no longer check the values of TZif + files’ standard/wall and UT/local indicators, which these + functions have not used since 2026a’s removal of the old + posixrules feature. + + tzcode has been ported to Haiku. + + localtime.c now works again by default on AIX and DragonFly BSD. + + zic now rejects ‘:’ and ‘\’ in Zone and Link names when running on + Microsoft Windows. (Problem reported by David Diaz.) + + Changes to documentation + + URLs for release tarballs in tz-link.html have been updated to + reflect their new canonical URLs on data.iana.org. + + Release 2026c - 2026-07-08 10:23:58 -0700 Briefly: @@ -15,7 +97,13 @@ Release 2026c - 2026-07-08 10:23:58 -0700 CST. Although the change to permanent -06 legally took place on 2026-06-18, temporarily model the change to occur on 2026-11-01 at 02:00 instead, for the same reason we introduced a similarly - temporary hack for British Columbia in 2026b. + temporary hack for British Columbia in 2026b. (Caution: see + “NOTE FOR 2026b TEMPORARY HACK FOR CLDR AND CANADA” below.) + + As the change affects both America/Edmonton and its backward + compatibility link, the obsolescent setting TZ="Canada/Mountain" + will now use the abbreviation CST for affected timestamps, + akin to TZ="Canada/Pacific" behavior introduced in 2026b. Although another TZDB release will likely be needed soon because Northwest Territories will likely follow Alberta, the legal @@ -67,6 +155,7 @@ Release 2026b - 2026-04-22 23:06:43 -0700 Briefly: British Columbia moved to permanent -07 on 2026-03-09. + zic no longer mishandles a last transition to a new time type. Some more overflow bugs have been fixed in zic. Changes to future timestamps @@ -79,9 +168,33 @@ Release 2026b - 2026-04-22 23:06:43 -0700 limitation in CLDR 48.1 (2026-01-08). This temporary hack is planned to be removed after CLDR is fixed. + To match longstanding practice for -07 standard time in North + America, such as for America/Dawson, America/Dawson_Creek, + America/Fort_Nelson and America/Whitehorse, affected BC + timestamps use the abbreviation MST. As the change affects both + America/Vancouver and its backward compatibility link, the + obsolescent setting TZ="Canada/Pacific" will now use the + abbreviation MST. Future TZDB releases may change the + abbreviation if something else becomes popular across areas + observing -07, and may change it to "-07" if no alphabetic + consensus emerges. + Changes to code zic no longer mishandles a last transition to a new time type. + NOTE FOR 2026b TEMPORARY HACK FOR CLDR AND CANADA: + This zic fix is needed for the temporary hack (mentioned above) + that works around the Canadian timekeeping bug in Unicode CLDR. + Without the fix, the temporary hack causes zic versions 2023d + through 2026a, in their default mode that generates slim output, + to generate a TZif file that violates Internet RFC 9636 §3.3. + The buggy file in turn causes some TZif readers, including tzcode + itself, to ignore America/Vancouver’s 2026-11-01 02:00 transition + from PDT (tm_isdst=1) to MST (tm_isdst=0). Although the buggy + file does not cause any known TZif reader to mishandle UT offsets, + caution is advised when using zic 2023d through 2026a to compile + data from more-recent tz releases. To work around this problem + when using these older zic versions, use ‘zic -b fat’. zic no longer overflows a buffer when generating a TZ string like "PST-167:59:58PDT-167:59:59,M11.5.6/-167:59:59,M12.5.6/-167:59:59", @@ -10,7 +10,7 @@ locations around the globe. It is updated periodically to reflect changes made by political bodies to time zone boundaries, UTC offsets, and daylight-saving rules. -See <https://www.iana.org/time-zones/repository/tz-link.html> or the +See <https://data.iana.org/time-zones/tz-link.html> or the file tz-link.html for how to acquire the code and data. Once acquired, read the leading comments in the file ‘Makefile’ @@ -1544,9 +1544,21 @@ Zone Asia/Jayapura 9:22:48 - LMT 1932 Nov # leap year calculation involved. There has never been any serious # plan to change that law.... # -# From Paul Eggert (2022-06-30): -# Go with Pournader for 1935 through spring 1979, and for timestamps -# after August 1991; go with with Shanks & Pottenger for other timestamps. +# From N.F. Hase (2026-07-26): +# Ettela'at (Tehran daily) printed a daily panel headed "taqvim-e +# Ettela'at / sa'at-ha-ye shar'i", attributed to Dr. Riyazi Kermani. +# Each panel gives today's maghrib followed by fajr, sunrise, solar noon +# and maghrib for the next day, together with the Iranian, Hijri and +# Gregorian dates.... 26 May 1979 (5 Khordād 1358) +# https://commons.wikimedia.org/wiki/File:Ettelaat13580305.pdf +# ... That also matches Movahedi's wording, that the government +# returned to DST on 26 May, and the note in the 2022 thread that the +# change was announced one day in advance on 25 May. +# +# From Paul Eggert (2026-07-27): +# Go with Pournader for 1935 through spring 1979 (with the last +# transition clarified by Hase), and for timestamps after August 1991; +# go with Shanks & Pottenger for other timestamps. # Go with Santoni's citation of the UIT for fall 1977, as 20 October 1977 # is 28 Mehr 1356, consistent with the "Mehr" in Pournader's source. # Assume that the UIT's "1930" is UTC, i.e., 24:00 local time. @@ -1591,13 +1603,13 @@ Zone Asia/Jayapura 9:22:48 - LMT 1932 Nov # # Rule NAME FROM TO - IN ON AT SAVE LETTER/S # Work around a bug in zic 2022a and earlier. -Rule Iran 1910 only - Jan 1 00:00 0 - +Rule Iran 1910 only - Jan 1 0:00 0 - # Rule Iran 1977 only - Mar 21 23:00 1:00 - Rule Iran 1977 only - Oct 20 24:00 0 - Rule Iran 1978 only - Mar 24 24:00 1:00 - -Rule Iran 1978 only - Aug 5 01:00 0 - -Rule Iran 1979 only - May 26 24:00 1:00 - +Rule Iran 1978 only - Aug 5 1:00 0 - +Rule Iran 1979 only - May 26 0:00 1:00 - Rule Iran 1979 only - Sep 18 24:00 0 - Rule Iran 1980 only - Mar 20 24:00 1:00 - Rule Iran 1980 only - Sep 22 24:00 0 - @@ -15,7 +15,8 @@ # typically use this file for backward compatibility. # This file is divided into sections, one for each major reason for a -# backward compatibility link. Each section is sorted by link name. +# backward compatibility link or zone. Each section of links is +# sorted by name. # A "#= TARGET1" comment labels each link inserted only because some # .zi parsers (including tzcode through 2022e) mishandle links to links. @@ -46,7 +47,6 @@ Link America/Noronha Brazil/DeNoronha Link America/Sao_Paulo Brazil/East Link America/Manaus Brazil/West Link Europe/Brussels CET -Link America/Chicago CST6CDT Link America/Halifax Canada/Atlantic Link America/Winnipeg Canada/Central # This line is commented out, as the name exceeded the 14-character limit @@ -63,7 +63,6 @@ Link Pacific/Easter Chile/EasterIsland Link America/Havana Cuba Link Europe/Athens EET Link America/Panama EST -Link America/New_York EST5EDT Link Africa/Cairo Egypt Link Europe/Dublin Eire # Vanguard section, for most .zi parsers. @@ -104,7 +103,6 @@ Link Pacific/Kwajalein Kwajalein Link Africa/Tripoli Libya Link Europe/Brussels MET Link America/Phoenix MST -Link America/Denver MST7MDT Link America/Tijuana Mexico/BajaNorte Link America/Mazatlan Mexico/BajaSur Link America/Mexico_City Mexico/General @@ -326,6 +324,52 @@ Link Europe/Kyiv Europe/Kiev # However, for various reasons many users expect to find it under Europe. Link Asia/Nicosia Europe/Nicosia Link Pacific/Honolulu HST -Link America/Los_Angeles PST8PDT Link Pacific/Guadalcanal Pacific/Ponape #= Pacific/Pohnpei Link Pacific/Port_Moresby Pacific/Truk #= Pacific/Chuuk + + +# The backward-compatibility zones PST8PDT, MST7MDT, CST6CDT, and EST5EDT + +# Near-copy of US rules in the northamerica file, +# so that this file can be compiled separately. +# To conform to POSIX, this copy uses D instead of W for War and P for Peace. +# Rule NAME FROM TO - IN ON AT SAVE LETTER/S +Rule USback 1918 1919 - Mar lastSun 2:00 1:00 D +Rule USback 1918 1919 - Oct lastSun 2:00 0 S +Rule USback 1942 only - Feb 9 2:00 1:00 D # War +Rule USback 1945 only - Aug 14 23:00u 1:00 D # Peace +Rule USback 1945 only - Sep 30 2:00 0 S +Rule USback 1967 2006 - Oct lastSun 2:00 0 S +Rule USback 1967 1973 - Apr lastSun 2:00 1:00 D +Rule USback 1974 only - Jan 6 2:00 1:00 D +Rule USback 1975 only - Feb lastSun 2:00 1:00 D +Rule USback 1976 1986 - Apr lastSun 2:00 1:00 D +Rule USback 1987 2006 - Apr Sun>=1 2:00 1:00 D +Rule USback 2007 max - Mar Sun>=8 2:00 1:00 D +Rule USback 2007 max - Nov Sun>=1 2:00 0 S + +# From Arthur David Olson (2005-12-19): +# We generate the files specified below to guard against old files with +# obsolete information being left in the time zone binary directory. +# We limit the list to names that have appeared in previous versions of +# this time zone package. +# We do these as separate Zones rather than as Links to avoid problems if +# a particular place changes whether it observes DST. +# +# From Paul Eggert (2026-07-24): +# These zones are for backward compatibility with Unix System V (1983). +# They are ahistorical, in that they pretend standard time extends +# backward indefinitely into the past. +# They use USback (not US) rules so that they conform to POSIX instead +# of using abbreviations like EWT for Eastern War Time during World War II. +# The zones are here, not in the northamerica file, to lessen +# confusion downstream by making it clear that the zones are present +# only for backward compatibility. +# New software should use settings like TZ='America/New_York' instead +# of these backwards-compatibility zones. +# +# Zone NAME STDOFF RULES FORMAT [UNTIL] +Zone PST8PDT -8:00 USback P%sT +Zone MST7MDT -7:00 USback M%sT +Zone CST6CDT -6:00 USback C%sT +Zone EST5EDT -5:00 USback E%sT @@ -927,9 +927,10 @@ Zone America/Tortola -4:18:28 - LMT 1911 Jul # Road Town -4:00 - AST # Yellowknife, Northwest Territories -Zone America/Yellowknife 0 - -00 1935 # Yellowknife founded? - -7:00 NT_YK M%sT 1980 - -7:00 Canada M%sT +# Commented out as too wrong to be useful. +#Zone America/Yellowknife 0 - -00 1935 # Yellowknife founded? +# -7:00 NT_YK M%sT 1980 +# -7:00 Canada M%sT # Dumont d'Urville, Île des Pétrels, -6640+14001, since 1956-11 # <https://en.wikipedia.org/wiki/Dumont_d'Urville_Station> (2005-12-05) @@ -1836,12 +1837,8 @@ Zone Pacific/Wallis 12:15:20 - LMT 1901 # Zone NAME STDOFF RULES FORMAT [UNTIL] Zone HST -10:00 - HST -Zone PST8PDT -8:00 US P%sT Zone MST -7:00 - MST -Zone MST7MDT -7:00 US M%sT -Zone CST6CDT -6:00 US C%sT Zone EST -5:00 - EST -Zone EST5EDT -5:00 US E%sT Zone WET 0:00 EU WE%sT Zone CET 1:00 C-Eur CE%sT Zone MET 1:00 C-Eur ME%sT diff --git a/northamerica b/northamerica index 3c53eb602ec0..e5f858272c8b 100644 --- a/northamerica +++ b/northamerica @@ -96,7 +96,7 @@ # was the first nationwide legal time standard, and apparently # time was just called "Standard Time" or "Daylight Saving Time". -# From Paul Eggert (2019-06-04): +# From Paul Eggert (2019-06-04) and Tim Parenti (2026-07-21): # Here is the legal basis for the US federal rules. # * Public Law 65-106 (1918-03-19) implemented standard and daylight saving # time for the first time across the US, springing forward on March's last @@ -111,10 +111,15 @@ # * Public Law 89-387 (1966-04-13) reinstituted a national standard for DST, # from April's last Sunday to October's last Sunday, effective 1967. # https://www.govinfo.gov/content/pkg/STATUTE-80/pdf/STATUTE-80-Pg107.pdf -# * Public Law 93-182 (1973-12-15) moved the 1974 spring-forward to 01-06. +# * Public Law 93-182 (1973-12-15) applied DST year-round as an emergency +# measure. It took effect on the fourth Sunday after its enactment, +# effectively moving the 1974 spring-forward to 01-06. # https://www.govinfo.gov/content/pkg/STATUTE-87/pdf/STATUTE-87-Pg707.pdf -# * Public Law 93-434 (1974-10-05) moved the 1975 spring-forward to -# February's last Sunday. +# It was meant to last for 16 months or two winters (through 1975-04-27); +# however... +# * Public Law 93-434 (1974-10-05) created an exemption for much of the second +# winter, restoring standard time from the usual date of 1974-10-27 while +# moving the 1975 spring-forward up to February's last Sunday. # https://www.govinfo.gov/content/pkg/STATUTE-88/pdf/STATUTE-88-Pg1209.pdf # * Public Law 99-359 (1986-07-08) moved the spring-forward to April's first # Sunday. @@ -575,8 +580,12 @@ Zone America/Los_Angeles -7:52:58 - LMT 1883 Nov 18 20:00u # Russian time, and it is more accurate to model this than to ignore it. # The database format requires an exact transition time; use the Russian # salute as a somewhat-arbitrary time for the formal transfer of control for -# all of Alaska. Sitka's UTC offset is -9:01:13; adjust its 15:30 to the -# local times of other Alaskan locations so that they change simultaneously. +# all of Alaska. +# +# From Tim Parenti (2026-08-26): +# Sitka's UT offset changed from +14:58:47 to -9:01:13, so effectuate this +# change at 15:30:00 +14:58:47, or 1867-10-19 00:31:13 UT in the Alaskan +# locations below. # From Paul Eggert (2014-07-18): # One opinion of the early 1980s turmoil in Alaska over time zones and @@ -656,7 +665,7 @@ Zone America/Los_Angeles -7:52:58 - LMT 1883 Nov 18 20:00u # and are west of 169.5° W. # Zone NAME STDOFF RULES FORMAT [UNTIL] -Zone America/Juneau 15:02:19 - LMT 1867 Oct 19 15:33:32 +Zone America/Juneau 15:02:19 - LMT 1867 Oct 19 0:31:13u -8:57:41 - LMT 1900 Aug 20 12:00 -8:00 - PST 1942 -8:00 US P%sT 1946 @@ -666,7 +675,7 @@ Zone America/Juneau 15:02:19 - LMT 1867 Oct 19 15:33:32 -8:00 US P%sT 1983 Oct 30 2:00 -9:00 US Y%sT 1983 Nov 30 -9:00 US AK%sT -Zone America/Sitka 14:58:47 - LMT 1867 Oct 19 15:30 +Zone America/Sitka 14:58:47 - LMT 1867 Oct 19 0:31:13u -9:01:13 - LMT 1900 Aug 20 12:00 -8:00 - PST 1942 -8:00 US P%sT 1946 @@ -674,7 +683,7 @@ Zone America/Sitka 14:58:47 - LMT 1867 Oct 19 15:30 -8:00 US P%sT 1983 Oct 30 2:00 -9:00 US Y%sT 1983 Nov 30 -9:00 US AK%sT -Zone America/Metlakatla 15:13:42 - LMT 1867 Oct 19 15:44:55 +Zone America/Metlakatla 15:13:42 - LMT 1867 Oct 19 0:31:13u -8:46:18 - LMT 1900 Aug 20 12:00 -8:00 - PST 1942 -8:00 US P%sT 1946 @@ -684,14 +693,14 @@ Zone America/Metlakatla 15:13:42 - LMT 1867 Oct 19 15:44:55 -9:00 US AK%sT 2018 Nov 4 2:00 -8:00 - PST 2019 Jan 20 2:00 -9:00 US AK%sT -Zone America/Yakutat 14:41:05 - LMT 1867 Oct 19 15:12:18 +Zone America/Yakutat 14:41:05 - LMT 1867 Oct 19 0:31:13u -9:18:55 - LMT 1900 Aug 20 12:00 -9:00 - YST 1942 -9:00 US Y%sT 1946 -9:00 - YST 1969 -9:00 US Y%sT 1983 Nov 30 -9:00 US AK%sT -Zone America/Anchorage 14:00:24 - LMT 1867 Oct 19 14:31:37 +Zone America/Anchorage 14:00:24 - LMT 1867 Oct 19 0:31:13u -9:59:36 - LMT 1900 Aug 20 12:00 -10:00 - AST 1942 -10:00 US A%sT 1967 Apr @@ -699,7 +708,7 @@ Zone America/Anchorage 14:00:24 - LMT 1867 Oct 19 14:31:37 -10:00 US AH%sT 1983 Oct 30 2:00 -9:00 US Y%sT 1983 Nov 30 -9:00 US AK%sT -Zone America/Nome 12:58:22 - LMT 1867 Oct 19 13:29:35 +Zone America/Nome 12:58:22 - LMT 1867 Oct 19 0:31:13u -11:01:38 - LMT 1900 Aug 20 12:00 -11:00 - NST 1942 -11:00 US N%sT 1946 @@ -708,7 +717,7 @@ Zone America/Nome 12:58:22 - LMT 1867 Oct 19 13:29:35 -11:00 US B%sT 1983 Oct 30 2:00 -9:00 US Y%sT 1983 Nov 30 -9:00 US AK%sT -Zone America/Adak 12:13:22 - LMT 1867 Oct 19 12:44:35 +Zone America/Adak 12:13:22 - LMT 1867 Oct 19 0:31:13u -11:46:38 - LMT 1900 Aug 20 12:00 -11:00 - NST 1942 -11:00 US N%sT 1946 @@ -1937,7 +1946,7 @@ Zone America/Swift_Current -7:11:20 - LMT 1905 Sep # https://docs.assembly.ab.ca/LADDAR_files/docs/bills/bill/legislature_31/session_2/20251023_bill-031.pdf # would repeal the Daylight Saving Time Act in the Revised Statutes of Alberta # 2000 Chapter D-5: -# https://kings-printer.alberta.ca/documents/Acts/D05.pdf +# https://web.archive.org/web/20240128134751/https://kings-printer.alberta.ca/documents/Acts/D05.pdf # ...and substitutes a new chapter with language that closely parallels the # original. The new title is the Official Time Act and will be numbered # Chapter O-5.7. The Act establishes a standard time of UTC−6 without @@ -1967,6 +1976,10 @@ Zone America/Swift_Current -7:11:20 - LMT 1905 Sep # term is reviewed by then for relevancy and need. This plan for possible # obsolescence affects neither timekeeping nor TZDB’s data, which do # not contain the string “Alberta Time”. +# +# From Tim Parenti (2026-07-21): +# The new Official Time Act is now in the Revised Statutes as Chapter O-5.7: +# https://kings-printer.alberta.ca/documents/Acts/O05p7.pdf # Rule NAME FROM TO - IN ON AT SAVE LETTER/S Rule Edm 1918 1919 - Apr Sun>=8 2:00 1:00 D @@ -1987,7 +2000,7 @@ Zone America/Edmonton -7:33:52 - LMT 1906 Sep -7:00 Edm M%sT 1987 -7:00 Canada M%sT 2026 Jun 18 # Temporary hack; see above. - -7:00 1:00 MDT 2026 Nov 1 2:00 + -7:00 Canada MDT 2026 Nov 1 2:00 # End of temporary hack. -6:00 - CST @@ -2061,23 +2074,42 @@ Zone America/Edmonton -7:33:52 - LMT 1906 Sep # -07 - accurate and clear in itself, but makes BC look odd vs neighbors # PacT - straightforward but novel abbreviation for Pacific Time -# From Chris Walton (2026-03-15): -# The Regional District of East Kootenay is planning to move to year-round -# Mountain Standard Time (MST) on November 1, 2026.... -# https://www.rdek.bc.ca/news/entry/rdek_board_moves_to_transition_to_year_round_mountain_standard_time -# (2026-03-17): -# The final decision East Kootenay made a few days ago may turn out not to -# be final after all. They are going to reopen the debate next month! +# From Tim Parenti (2026-08-21): +# In the southeast of the province, the Regional District of East Kootenay +# (RDEK), Columbia Shuswap Regional District’s Electoral Area A (Rural Golden), +# and the Town of Golden have all historically been aligned with neighboring +# Alberta and use America/Edmonton. +# +# Shortly after the BC provincial government announced its adoption of +# year-round -07, the RDEK Board of Directors on 2026-03-13 initially voted +# narrowly, 8–7, that it would fall back one last time to rejoin the rest of BC +# on -07 from November 2026. However, citing the rushed decision and lack of +# feedback from residents, Mayor Steve Fairbairn of Elkford used his power to +# ask the question be called a second time, remarking, “Pardon the pun, but +# this is not a time-sensitive issue,” and the initial decision was rescinded +# by the RDEK Board at its 2026-04-10 meeting. # https://www.cbc.ca/news/canada/british-columbia/what-time-is-it-in-the-east-kootenay-debate-9.7132624 -# From Paul Eggert (2026-03-17): -# Mayor Steve Fairbairn of Elkford asked the question be called a second time, -# saying, “Pardon the pun, but this is not a time-sensitive issue.” -# For now, merely mention the potential change in these comments. -# If it happens it would likely affect clocks starting 2027-03-14 at 02:00. -# From Tim Parenti (2026-05-14): -# RDEK has historically been aligned with neighboring Alberta. With the latter -# now opting to stay on -06 year-round, if RDEK does not follow, it would -# require a new zone for the Cranbrook area. +# In the ensuing months, after Alberta announced and implemented its similar +# shift to “permanent DST” (see above), RDEK coordinated a public survey across +# all of the relevant BC communities. The survey found 89% of respondents in +# favor of ending seasonal time changes, with 66% of that group preferring to +# remain aligned with Alberta time on year-round -06 instead of the rest of BC. +# In line with those results, the RDEK Board adopted year-round -06 at its +# 2026-08-14 meeting. +# https://www.cbc.ca/news/canada/british-columbia/east-kootenay-stops-changing-clocks-9.7308201 +# +# From Tim Parenti (2026-09-10): +# Although on 2026-09-01 the Town of Golden voted instead to split its +# timekeeping practice from RDEK and rejoin BC on year-round -07, this was met +# with significant pushback from residents in Golden and CSRD Area A. In light +# of these public comments, CSRD voted on 2026-09-10 to defer its decision on +# timekeeping in Area A “to gather and assess further information before a +# decision is implemented”. As such, at time of writing, it seems likely that +# Golden may soon revisit its decision as well. +# +# For now, these areas remain aligned with America/Edmonton, but if they +# diverge, a new zone with a name like 'America/Brit_Columbia/Golden' would be +# needed. # Rule NAME FROM TO - IN ON AT SAVE LETTER/S Rule Vanc 1918 only - Apr 14 2:00 1:00 D @@ -2094,7 +2126,7 @@ Zone America/Vancouver -8:12:28 - LMT 1884 -8:00 Vanc P%sT 1987 -8:00 Canada P%sT 2026 Mar 9 # Temporary hack; see above. - -8:00 1:00 PDT 2026 Nov 1 2:00 + -8:00 Canada PDT 2026 Nov 1 2:00 # End of temporary hack. -7:00 - MST Zone America/Dawson_Creek -8:00:56 - LMT 1884 @@ -2429,15 +2461,17 @@ Zone America/Fort_Nelson -8:10:47 - LMT 1884 # end seasonal time changes until Alberta does." # https://www.cbc.ca/news/canada/north/nwt-ends-daylight-saving-9.7170964 # -# From Tim Parenti (2026-06-19), per James Bellaire (2026-06-02): -# Much of NWT has, to date, been represented by America/Edmonton, which alias -# America/Yellowknife links to. While Bill 13 (assented to 2021-03-31) would -# enable NWT's proposed change mirroring Alberta's, at time of writing it has -# not yet been formally enacted; if it doesn't move forward as expected, -# America/Yellowknife would need to become its own zone as Alberta has stopped -# changing its clocks. -# If it does go ahead, draft changes to America/Inuvik, which represents the -# remainder of NWT, are commented below. +# From Tim Parenti (2026-07-24): +# Now that Alberta has adopted year-round -06, NWT plans to follow through with +# the same. Bill 13 of the 19th Assembly's 2nd Session, assented to +# 2021-03-31, provides the NWT Commissioner in Executive Council with authority +# to fix a year-round standard time: +# https://www.ntlegislativeassembly.ca/sites/default/files/legacy/bill_13_-_reprint_-_interpretation_a.pdf +# +# From Paul Eggert (2026-08-21): +# The regulations were registered 2026-08-18 and came into force today: +# https://www.justice.gov.nt.ca/en/files/legislation/interpretation/interpretation.r2.pdf +# Use a temporary hack like Alberta’s. # Rule NAME FROM TO - IN ON AT SAVE LETTER/S Rule NT_YK 1918 only - Apr 14 2:00 1:00 D @@ -2480,11 +2514,11 @@ Zone America/Cambridge_Bay 0 - -00 1920 # trading post est.? Zone America/Inuvik 0 - -00 1953 # Inuvik founded -8:00 NT_YK P%sT 1979 Apr lastSun 2:00 -7:00 NT_YK M%sT 1980 - -7:00 Canada M%sT -# Assuming Northwest Territories follows Alberta in abolishing seasonal time -# changes, replace the above line with something like: -# -7:00 Canada M%sT 2026 Nov 1 2:00 -# -6:00 - CST + -7:00 Canada M%sT 2026 Aug 21 + # Temporary hack; see above. + -7:00 Canada MDT 2026 Nov 1 2:00 + # End of temporary hack. + -6:00 - CST Zone America/Whitehorse -9:00:12 - LMT 1900 Aug 20 -9:00 NT_YK Y%sT 1965 -9:00 Yukon Y%sT 1966 Feb 27 0:00 diff --git a/southamerica b/southamerica index bcd4abdfa42c..2a9d60a02c9e 100644 --- a/southamerica +++ b/southamerica @@ -1330,20 +1330,9 @@ Zone America/Rio_Branco -4:31:12 - LMT 1914 # promulgated 2022-07-14 and published 2022-08-13: # https://www.diariooficial.interior.gob.cl/publicaciones/2022/08/13/43327/01/2172567.pdf # https://www.bcn.cl/leychile/navegar?idNorma=1179983 -# -# From Paul Eggert (2022-08-17): -# Although the presidential decree stops at fall 2026, assume that -# similar DST rules will continue thereafter. -# From Paul Eggert (2025-01-15): -# Diario Regional Aysén's Sebastián Martel reports that 94% of Aysén -# citizens polled in November favored changing the rules from -# -04/-03-with-DST to -03 all year... -# https://www.diarioregionalaysen.cl/noticia/actualidad/2024/12/presentan-decision-que-gano-la-votacion-sobre-el-cambio-del-huso-horario-en-aysen -# # From Yonathan Dossow (2025-03-20): -# [T]oday we have more confirmation of the change. [Aysén] region will keep -# UTC-3 all year... +# [Aysén] region will keep UTC-3 all year... # https://www.cnnchile.com/pais/region-de-aysen-mantendra-horario-de-verano-todo-el-ano_20250320/ # https://www.latercera.com/nacional/noticia/tras-consulta-ciudadana-region-de-aysen-mantendra-el-horario-de-verano-durante-todo-el-ano/ # https://x.com/min_interior/status/1902692504270672098 @@ -1355,6 +1344,14 @@ Zone America/Rio_Branco -4:31:12 - LMT 1914 # https://www.bcn.cl/leychile/Navegar?idNorma=1211955 # Model this as a change to standard offset effective 2025-03-20. +# From Paul Eggert (2026-08-11): +# Chile’s timekeeping regime is renewed by Decreto 98 of 2026 of the +# Ministry of the Interior, Undersecretariat of the Interior, +# promulgated 2026-06-30 and published 2026-07-02: +# https://www.bcn.cl/leychile/navegar?idNorma=1225724 +# Although this decree stops at fall 2029, assume that +# similar DST rules will continue thereafter. + # Rule NAME FROM TO - IN ON AT SAVE LETTER/S Rule Chile 1927 1931 - Sep 1 0:00 1:00 - Rule Chile 1928 1932 - Apr 1 0:00 0 - @@ -1472,13 +1469,19 @@ Zone Antarctica/Palmer 0 - -00 1965 # Milne gives 4:56:16.4 for Bogotá time in 1899. He writes, # "A variation of fifteen minutes in the public clocks of Bogota is not rare." +# From Paul Eggert (2026-07-17): +# The 1992 spring forward was May 2 at 00:00. See: +# Jiménez FA. La noche en que Colombia perdió una hora para encarar el apagón, +# ¿se repetirá la historia en 2026? El Colombiano. 2026-06-21. +# https://www.elcolombiano.com/negocios/colombia-perdio-una-hora-para-evitar-apagon-horario-gaviria-LF37983109 + # From Alois Treindl (2022-11-10): # End of time change in Colombia 1993 ... should be 6 February 24h ... # DECRETO 267 DE 1993 # https://www.suin-juriscol.gov.co/viewDocument.asp?ruta=Decretos/1061335 # Rule NAME FROM TO - IN ON AT SAVE LETTER/S -Rule CO 1992 only - May 3 0:00 1:00 - +Rule CO 1992 only - May 2 0:00 1:00 - Rule CO 1993 only - Feb 6 24:00 0 - # Zone NAME STDOFF RULES FORMAT [UNTIL] #STDOFF -4:56:16.4 diff --git a/theory.html b/theory.html index 8f76aaf0b3c8..d56e1a79df46 100644 --- a/theory.html +++ b/theory.html @@ -12,6 +12,7 @@ </head> <body> +<main> <h1>Theory and pragmatics of the <code><abbr>tz</abbr></code> code and data</h1> <nav> <ul> @@ -26,10 +27,10 @@ <li><a href="#leapsec">Leap seconds</a></li> <li><a href="#calendar">Calendrical issues</a></li> <li><a href="#planets">Time and time zones off earth</a></li> + <li><a href="#see-also">See also</a></li> </ul> </nav> -<section> <h2 id="scope">Scope of the <code><abbr>tz</abbr></code> database</h2> <p> The <a @@ -112,9 +113,6 @@ It does not always make sense to talk about a timezone’s “base offset”, which is not necessarily a single number. </p> -</section> - -<section> <h2 id="naming">Timezone identifiers</h2> <p> Each timezone has a name that uniquely identifies the timezone. @@ -345,8 +343,7 @@ These legacy names are mostly defined in the file "<code>etcetera</code>". Also, the file "<code>backward</code>" defines the legacy names <code>Etc/GMT0</code>, <code>Etc/GMT-0</code>, <code>Etc/GMT+0</code>, -<code>GMT0</code>, <code>GMT-0</code> and <code>GMT+0</code>, -and the file "<code>northamerica</code>" defines the legacy names +<code>GMT0</code>, <code>GMT-0</code>, <code>GMT+0</code>, <code>EST5EDT</code>, <code>CST6CDT</code>, <code>MST7MDT</code>, and <code>PST8PDT</code>. </li> @@ -387,11 +384,11 @@ and <code>zone.tab</code>. <p> The database defines each timezone name to be a zone, or a link to a zone. -The source file <code>backward</code> defines links for backward -compatibility; it does not define zones. +The source file <code>backward</code> defines links +and a few zones for backward compatibility. Although <code>backward</code> was originally designed to be optional, nowadays distributions typically use it -and no great weight should be attached to whether a link +and no great weight should be attached to whether a link or zone is defined in <code>backward</code> or in some other file. The source file <code>etcetera</code> defines names that may be useful on platforms that do not support proleptic <code>TZ</code> strings @@ -404,9 +401,7 @@ second information on platforms that support leap seconds. Another <code>etcetera</code> name, <code>GMT</code>, is used by older code releases. </p> -</section> -<section> <h2 id="abbreviations">Time zone abbreviations</h2> <p> When this package is installed, it generates time zone abbreviations @@ -610,9 +605,7 @@ Israel. To avoid ambiguity, use numeric <abbr>UT</abbr> offsets like <code>-</code>0600 instead of time zone abbreviations like CST. </p> -</section> -<section> <h2 id="accuracy">Accuracy of the <code><abbr>tz</abbr></code> database</h2> <p> The <code><abbr>tz</abbr></code> database is not authoritative, and it @@ -876,9 +869,7 @@ merely because two locations differ in <abbr>LMT</abbr> or transitioned to standard time at different dates. </p> -</section> -<section> <h2 id="functions">Time and date functions</h2> <p> The <code><abbr>tz</abbr></code> code contains time and date functions @@ -1284,9 +1275,7 @@ The vestigial <abbr>API</abbr>s are: much the better. </li> </ul> -</section> -<section> <h2 id="stability">Interface stability</h2> <p> The <code><abbr>tz</abbr></code> code and data supply the following interfaces: @@ -1353,9 +1342,7 @@ than Bangkok by putting <samp>Asia/Bangkok</samp> in the event’s record, the application should be robust in the presence of timezone splits between now and the future time. </p> -</section> -<section> <h2 id="leapsec">Leap seconds</h2> <p> Leap seconds were introduced in 1972 to accommodate the @@ -1430,9 +1417,7 @@ Alternatively, you can install just one set of <abbr>TZif</abbr> files in the first place; see the <code>REDO</code> variable in this package’s <a href="https://en.wikipedia.org/wiki/Makefile">makefile</a>. </p> -</section> -<section> <h2 id="calendar">Calendrical issues</h2> <p> Calendrical issues are a bit out of scope for a time zone database, @@ -1446,22 +1431,30 @@ Other information and sources are given in the file "<code>calendars</code>" in the <code><abbr>tz</abbr></code> distribution. They sometimes disagree. </p> -</section> -<section> <h2 id="planets">Time and time zones off Earth</h2> <p> -The European Space Agency is <a -href="https://www.esa.int/Applications/Satellite_navigation/Telling_time_on_the_Moon">considering</a> -the establishment of a reference timescale for the Moon, which has +Efforts are underway to establish a reference timescale for the Moon, which has days roughly equivalent to 29.5 Earth days, and where relativistic effects cause clocks to tick slightly faster than on Earth. -Also, <abbr title="National Aeronautics and Space Administration">NASA</abbr> -has been <a +The European Space Agency <a +href="https://www.esa.int/Applications/Satellite_navigation/Telling_time_on_the_Moon">began +considering</a> the problem in 2023, and in 2024 +<abbr title="National Aeronautics and Space Administration">NASA</abbr> +was <a href="https://bidenwhitehouse.archives.gov/wp-content/uploads/2024/04/Celestial-Time-Standardization-Policy.pdf">ordered</a> to consider the establishment of Coordinated Lunar Time (<abbr>LTC</abbr>). -It is not yet known whether the US and European efforts will result in -multiple timescales on the Moon. +In 2025 a team at China’s +<a href="https://en.wikipedia.org/wiki/Purple_Mountain_Observatory">Purple +Mountain Observatory</a> published +<a href="https://doi.org/10.1051/0004-6361/202557345">Lunar Time Ephemeris +440</a>, the first formal proposal for a standard +for Temps Coordonné Lunaire (<abbr>TCL</abbr>). +A <a href="https://www.bipm.org/documents/20126/284836054/CGPM-2026-Draft-Resolutions.pdf">draft +resolution of the 13–15 October 2026 General Conference on Weights +and Measures</a> recommends that the <a href="https://www.bipm.org/en/">Bureau +International des Poids et Mesures</a> collaborate with space agencies +and other organizations on this matter. </p> <p> @@ -1583,7 +1576,15 @@ Sources for time on other planets: (2016-01-20). </li> </ul> -</section> +</main> + +<aside> +<h2 id="see-also">See also</h2> +<ul> +<li><a href="tz-link.html">Time zone and daylight saving time data</a></li> +<li><a href="tz-art.html">Time and the arts</a></li> +</ul> +</aside> <footer> <hr> @@ -1 +1 @@ -2026c +2026d @@ -123,7 +123,7 @@ CA +5024-10439 America/Regina CST - SK (most areas) CA +5017-10750 America/Swift_Current CST - SK (midwest) CA +5333-11328 America/Edmonton CST - AB, BC(E), NT(E), SK(W) CA +690650-1050310 America/Cambridge_Bay Mountain - NU (west) -CA +682059-1334300 America/Inuvik Mountain - NT (west) +CA +682059-1334300 America/Inuvik CST - NT (west) CA +4916-12307 America/Vancouver MST - BC (most areas) CA +4906-11631 America/Creston MST - BC (Creston) CA +5546-12014 America/Dawson_Creek MST - BC (Dawson Cr, Ft St John) diff --git a/zone1970.tab b/zone1970.tab index 635eabcbf2d3..0c6a15c5be41 100644 --- a/zone1970.tab +++ b/zone1970.tab @@ -114,7 +114,7 @@ CA +5024-10439 America/Regina CST - SK (most areas) CA +5017-10750 America/Swift_Current CST - SK (midwest) CA +5333-11328 America/Edmonton CST - AB, BC(E), NT(E), SK(W) CA +690650-1050310 America/Cambridge_Bay Mountain - NU (west) -CA +682059-1334300 America/Inuvik Mountain - NT (west) +CA +682059-1334300 America/Inuvik CST - NT (west) CA +4916-12307 America/Vancouver MST - BC (most areas) CA +5546-12014 America/Dawson_Creek MST - BC (Dawson Cr, Ft St John) CA +5848-12242 America/Fort_Nelson MST - BC (Ft Nelson) diff --git a/zonenow.tab b/zonenow.tab index 9c3a8cf3c1b5..1c9b44b0499b 100644 --- a/zonenow.tab +++ b/zonenow.tab @@ -65,10 +65,10 @@ XX +4916-12307 America/Vancouver Mountain Standard (MST) - British Columbia (mos XX +332654-1120424 America/Phoenix Mountain Standard (MST) - Arizona; western Mexico; Yukon # # -07/-06 - MST/MDT (North America DST) -XX +394421-1045903 America/Denver Mountain (MST/MDT) - US; Mexico near US border; northern Canada +XX +394421-1045903 America/Denver Mountain (MST/MDT) - US; Mexico near US border; western Nunavut # # -07/-06 - MST/MDT (North America DST) until 2026-11-01 02:00; then CST -XX +5333-11328 America/Edmonton Central Standard (CST) - Alberta and some neighbors +XX +5333-11328 America/Edmonton Central Standard (CST) - Alberta, NWT, and some neighbors # # -06 XX -0054-08936 Pacific/Galapagos Galápagos |