diff options
| author | Philip Paeps <philip@FreeBSD.org> | 2024-02-02 01:53:59 +0000 |
|---|---|---|
| committer | Philip Paeps <philip@FreeBSD.org> | 2024-02-02 01:53:59 +0000 |
| commit | 76e31da7ab276bcd66122762d712fb99590f4d3a (patch) | |
| tree | d99dab2786b89a9ca35f59f4c88749649ad859e7 | |
| parent | 893fe32cd21ed460558d04ec8d860ad7174e42a1 (diff) | |
Import tzdata 2024avendor/tzdata/tzdata2024a
| -rw-r--r-- | Makefile | 53 | ||||
| -rw-r--r-- | NEWS | 68 | ||||
| -rw-r--r-- | africa | 8 | ||||
| -rw-r--r-- | asia | 174 | ||||
| -rw-r--r-- | australasia | 14 | ||||
| -rw-r--r-- | checknow.awk | 2 | ||||
| -rw-r--r-- | etcetera | 2 | ||||
| -rw-r--r-- | europe | 29 | ||||
| -rw-r--r-- | leap-seconds.list | 373 | ||||
| -rw-r--r-- | leapseconds | 19 | ||||
| -rw-r--r-- | leapseconds.awk | 11 | ||||
| -rw-r--r-- | northamerica | 29 | ||||
| -rw-r--r-- | southamerica | 5 | ||||
| -rw-r--r-- | theory.html | 37 | ||||
| -rw-r--r-- | version | 2 | ||||
| -rw-r--r-- | zishrink.awk | 98 | ||||
| -rw-r--r-- | zonenow.tab | 4 |
17 files changed, 507 insertions, 421 deletions
@@ -53,7 +53,7 @@ DATAFORM= main LOCALTIME= Factory -# The POSIXRULES macro controls interpretation of POSIX-like TZ +# The POSIXRULES macro controls interpretation of POSIX-2017.1-like TZ # settings like TZ='EET-2EEST' that lack DST transition rules. # If POSIXRULES is '-', no template is installed; this is the default. # Any other value for POSIXRULES is obsolete and should not be relied on, as: @@ -274,7 +274,7 @@ LDLIBS= # -DTZ_DOMAINDIR=\"/path\" to use "/path" for gettext directory; # the default is system-supplied, typically "/usr/lib/locale" # -DTZDEFRULESTRING=\",date/time,date/time\" to default to the specified -# DST transitions for POSIX-style TZ strings lacking them, +# DST transitions for POSIX.1-2017-style TZ strings lacking them, # in the usual case where POSIXRULES is '-'. If not specified, # TZDEFRULESTRING defaults to US rules for future DST transitions. # This mishandles some past timestamps, as US DST rules have changed. @@ -340,9 +340,10 @@ GCC_DEBUG_FLAGS = -DGCC_LINT -g3 -O3 -fno-common \ # guess TM_GMTOFF from other macros; define NO_TM_GMTOFF to suppress this. # Similarly, if your system has a "zone abbreviation" field, define # -DTM_ZONE=tm_zone -# and define NO_TM_ZONE to suppress any guessing. Although these two fields -# not required by POSIX, a future version of POSIX is planned to require them -# and they are widely available on GNU/Linux and BSD systems. +# and define NO_TM_ZONE to suppress any guessing. +# Although these two fields are not required by POSIX.1-2017, +# POSIX 202x/D4 requires them and they are widely available +# on GNU/Linux and BSD systems. # # The next batch of options control support for external variables # exported by tzcode. In practice these variables are less useful @@ -352,7 +353,7 @@ GCC_DEBUG_FLAGS = -DGCC_LINT -g3 -O3 -fno-common \ # # -DHAVE_TZNAME=0 # do not support "tzname" # # -DHAVE_TZNAME=1 # support "tzname", which is defined by system library # # -DHAVE_TZNAME=2 # support and define "tzname" -# # to the "CFLAGS=" line. "tzname" is required by POSIX 1988 and later. +# # to the "CFLAGS=" line. "tzname" is required by POSIX.1-1988 and later. # # If not defined, the code attempts to guess HAVE_TZNAME from other macros. # # Warning: unless time_tz is also defined, HAVE_TZNAME=1 can cause # # crashes when combined with some platforms' standard libraries, @@ -362,8 +363,8 @@ GCC_DEBUG_FLAGS = -DGCC_LINT -g3 -O3 -fno-common \ # # -DUSG_COMPAT=0 # do not support # # -DUSG_COMPAT=1 # support, and variables are defined by system library # # -DUSG_COMPAT=2 # support and define variables -# # to the "CFLAGS=" line; "timezone" and "daylight" are inspired by -# # Unix Systems Group code and are required by POSIX 2008 (with XSI) and later. +# # to the "CFLAGS=" line; "timezone" and "daylight" are inspired by Unix +# # Systems Group code and are required by POSIX.1-2008 and later (with XSI). # # If not defined, the code attempts to guess USG_COMPAT from other macros. # # # # To support the external variable "altzone", add @@ -427,7 +428,7 @@ GCC_DEBUG_FLAGS = -DGCC_LINT -g3 -O3 -fno-common \ # The name of a POSIX-like library archiver, its flags, C compiler, # linker flags, and 'make' utility. Ordinarily the defaults suffice. -# The commented-out values are the defaults specified by POSIX 202x/D3. +# The commented-out values are the defaults specified by POSIX.1-202x/D4. #AR = ar #ARFLAGS = -rv #CC = c17 @@ -439,6 +440,12 @@ GCC_DEBUG_FLAGS = -DGCC_LINT -g3 -O3 -fno-common \ LEAPSECONDS= +# Where to fetch leap-seconds.list from. +leaplist_URI = \ + https://hpiers.obspm.fr/iers/bul/bulc/ntp/leap-seconds.list +# The file is generated by the IERS Earth Orientation Centre, in Paris. +leaplist_TZ = Europe/Paris + # The zic command and its arguments. zic= ./zic @@ -471,7 +478,8 @@ AWK= awk # is typically nicer if it works. KSHELL= /bin/bash -# Name of curl <https://curl.haxx.se/>, used for HTML validation. +# Name of curl <https://curl.haxx.se/>, used for HTML validation +# and to fetch leap-seconds.list from upstream. CURL= curl # Name of GNU Privacy Guard <https://gnupg.org/>, used to sign distributions. @@ -718,6 +726,28 @@ leapseconds: $(LEAP_DEPS) -f leapseconds.awk leap-seconds.list >$@.out mv $@.out $@ +# Awk script to extract a Git-style author from leap-seconds.list comments. +EXTRACT_AUTHOR = \ + author_line { sub(/^.[[:space:]]*/, ""); \ + sub(/:[[:space:]]*/, " <"); \ + printf "%s>\n", $$0; \ + success = 1; \ + exit \ + } \ + /Questions or comments to:/ { author_line = 1 } \ + END { exit !success } + +# Fetch leap-seconds.list from upstream. +fetch-leap-seconds.list: + $(CURL) -OR $(leaplist_URI) + +# Fetch leap-seconds.list from upstream and commit it to the local repository. +commit-leap-seconds.list: fetch-leap-seconds.list + author=$$($(AWK) '$(EXTRACT_AUTHOR)' leap-seconds.list) && \ + date=$$(TZ=$(leaplist_TZ) stat -c%y leap-seconds.list) && \ + git commit --author="$$author" --date="$$date" -m'make $@' \ + leap-seconds.list + # Arguments to pass to submakes of install_data. # They can be overridden by later submake arguments. INSTALLARGS = \ @@ -1315,7 +1345,8 @@ zic.o: private.h tzfile.h tzdir.h version.h .PHONY: ALL INSTALL all .PHONY: check check_mild check_time_t_alternatives .PHONY: check_web check_zishrink -.PHONY: clean clean_misc dummy.zd force_tzs +.PHONY: clean clean_misc commit-leap-seconds.list dummy.zd +.PHONY: fetch-leap-seconds.list force_tzs .PHONY: install install_data maintainer-clean names .PHONY: posix_only posix_right public .PHONY: rearguard_signatures rearguard_signatures_version @@ -1,5 +1,73 @@ News for the tz database +Release 2024a - 2024-02-01 09:28:56 -0800 + + Briefly: + Kazakhstan unifies on UTC+5 beginning 2024-03-01. + Palestine springs forward a week later after Ramadan. + zic no longer pretends to support indefinite-past DST. + localtime no longer mishandles Ciudad Juárez in 2422. + + Changes to future timestamps + + Kazakhstan unifies on UTC+5. This affects Asia/Almaty and + Asia/Qostanay which together represent the eastern portion of the + country that will transition from UTC+6 on 2024-03-01 at 00:00 to + join the western portion. (Thanks to Zhanbolat Raimbekov.) + + Palestine springs forward a week later than previously predicted + in 2024 and 2025. (Thanks to Heba Hamad.) Change spring-forward + predictions to the second Saturday after Ramadan, not the first; + this also affects other predictions starting in 2039. + + Changes to past timestamps + + Asia/Ho_Chi_Minh's 1955-07-01 transition occurred at 01:00 + not 00:00. (Thanks to Đoàn Trần Công Danh.) + + From 1947 through 1949, Toronto's transitions occurred at 02:00 + not 00:00. (Thanks to Chris Walton.) + + In 1911 Miquelon adopted standard time on June 15, not May 15. + + Changes to code + + The FROM and TO columns of Rule lines can no longer be "minimum" + or an abbreviation of "minimum", because TZif files do not support + DST rules that extend into the indefinite past - although these + rules were supported when TZif files had only 32-bit data, this + stopped working when 64-bit TZif files were introduced in 1995. + This should not be a problem for realistic data, since DST was + first used in the 20th century. As a transition aid, FROM columns + like "minimum" are now diagnosed and then treated as if they were + the year 1900; this should suffice for TZif files on old systems + with only 32-bit time_t, and it is more compatible with bugs in + 2023c-and-earlier localtime.c. (Problem reported by Yoshito + Umaoka.) + + localtime and related functions no longer mishandle some + timestamps that occur about 400 years after a switch to a time + zone with a DST schedule. In 2023d data this problem was visible + for some timestamps in November 2422, November 2822, etc. in + America/Ciudad_Juarez. (Problem reported by Gilmore Davidson.) + + strftime %s now uses tm_gmtoff if available. (Problem and draft + patch reported by Dag-Erling Smørgrav.) + + Changes to build procedure + + The leap-seconds.list file is now copied from the IERS instead of + from its downstream counterpart at NIST, as the IERS version is + now in the public domain too and tends to be more up-to-date. + (Thanks to Martin Burnicki for liaisoning with the IERS.) + + Changes to documentation + + The strftime man page documents which struct tm members affect + which conversion specs, and that tzset is called. (Problems + reported by Robert Elz and Steve Summit.) + + Release 2023d - 2023-12-21 20:02:24 -0800 Briefly: @@ -30,6 +30,10 @@ # Milne J. Civil time. Geogr J. 1899 Feb;13(2):173-94. # https://www.jstor.org/stable/1774359 # +# For the 1911/1912 establishment of standard time in French possessions, see: +# Société Française de Physique, Recueil de constantes physiques (1913), +# page 752, 18b. +# # European-style abbreviations are commonly used along the Mediterranean. # For sub-Saharan Africa abbreviations were less standardized. # Previous editions of this database used WAT, CAT, SAT, and EAT @@ -113,7 +117,7 @@ Zone Atlantic/Cape_Verde -1:34:04 - LMT 1912 Jan 01 2:00u # Praia # Chad # Zone NAME STDOFF RULES FORMAT [UNTIL] -Zone Africa/Ndjamena 1:00:12 - LMT 1912 # N'Djamena +Zone Africa/Ndjamena 1:00:12 - LMT 1912 Jan 1 # N'Djamena 1:00 - WAT 1979 Oct 14 1:00 1:00 WAST 1980 Mar 8 1:00 - WAT @@ -139,7 +143,7 @@ Zone Africa/Ndjamena 1:00:12 - LMT 1912 # N'Djamena # Inaccessible, Nightingale: uninhabited # Zone NAME STDOFF RULES FORMAT [UNTIL] -Zone Africa/Abidjan -0:16:08 - LMT 1912 +Zone Africa/Abidjan -0:16:08 - LMT 1912 Jan 1 0:00 - GMT ############################################################################### @@ -2457,18 +2457,33 @@ Zone Asia/Amman 2:23:44 - LMT 1931 # effective December 21st, 2018.... # http://adilet.zan.kz/rus/docs/P1800000817 (russian language). +# From Zhanbolat Raimbekov (2024-01-19): +# Kazakhstan (all parts) switching to UTC+5 on March 1, 2024 +# https://www.gov.kz/memleket/entities/mti/press/news/details/688998?lang=ru +# [in Russian] +# (2024-01-20): https://primeminister.kz/ru/decisions/19012024-20 +# +# From Alexander Krivenyshev (2024-01-19): +# According to a different news and the official web site for the Ministry of +# Trade and Integration of the Republic of Kazakhstan: +# https://en.inform.kz/news/kazakhstan-to-switch-to-single-hour-zone-mar-1-54ad0b/ + # Zone NAME STDOFF RULES FORMAT [UNTIL] # # Almaty (formerly Alma-Ata), representing most locations in Kazakhstan -# This includes KZ-AKM, KZ-ALA, KZ-ALM, KZ-AST, KZ-BAY, KZ-VOS, KZ-ZHA, -# KZ-KAR, KZ-SEV, KZ-PAV, and KZ-YUZ. +# This includes Abai/Abay (ISO 3166-2 code KZ-10), Aqmola/Akmola (KZ-11), +# Almaty (KZ-19), Almaty city (KZ-75), Astana city (KZ-71), +# East Kazkhstan (KZ-63), Jambyl/Zhambyl (KZ-31), Jetisu/Zhetysu (KZ-33), +# Karaganda (KZ-35), North Kazakhstan (KZ-59), Pavlodar (KZ-55), +# Shyumkent city (KZ-79), Turkistan (KZ-61), and Ulytau (KZ-62). Zone Asia/Almaty 5:07:48 - LMT 1924 May 2 # or Alma-Ata 5:00 - +05 1930 Jun 21 6:00 RussiaAsia +06/+07 1991 Mar 31 2:00s 5:00 RussiaAsia +05/+06 1992 Jan 19 2:00s 6:00 RussiaAsia +06/+07 2004 Oct 31 2:00s - 6:00 - +06 -# Qyzylorda (aka Kyzylorda, Kizilorda, Kzyl-Orda, etc.) (KZ-KZY) + 6:00 - +06 2024 Mar 1 0:00 + 5:00 - +05 +# Qyzylorda (aka Kyzylorda, Kizilorda, Kzyl-Orda, etc.) (KZ-43) Zone Asia/Qyzylorda 4:21:52 - LMT 1924 May 2 4:00 - +04 1930 Jun 21 5:00 - +05 1981 Apr 1 @@ -2481,8 +2496,7 @@ Zone Asia/Qyzylorda 4:21:52 - LMT 1924 May 2 5:00 RussiaAsia +05/+06 2004 Oct 31 2:00s 6:00 - +06 2018 Dec 21 0:00 5:00 - +05 -# -# Qostanay (aka Kostanay, Kustanay) (KZ-KUS) +# Qostanay (aka Kostanay, Kustanay) (KZ-39) # The 1991/2 rules are unclear partly because of the 1997 Turgai # reorganization. Zone Asia/Qostanay 4:14:28 - LMT 1924 May 2 @@ -2493,9 +2507,9 @@ Zone Asia/Qostanay 4:14:28 - LMT 1924 May 2 5:00 RussiaAsia +05/+06 1991 Mar 31 2:00s 4:00 RussiaAsia +04/+05 1992 Jan 19 2:00s 5:00 RussiaAsia +05/+06 2004 Oct 31 2:00s - 6:00 - +06 - -# Aqtöbe (aka Aktobe, formerly Aktyubinsk) (KZ-AKT) + 6:00 - +06 2024 Mar 1 0:00 + 5:00 - +05 +# Aqtöbe (aka Aktobe, formerly Aktyubinsk) (KZ-15) Zone Asia/Aqtobe 3:48:40 - LMT 1924 May 2 4:00 - +04 1930 Jun 21 5:00 - +05 1981 Apr 1 @@ -2505,7 +2519,7 @@ Zone Asia/Aqtobe 3:48:40 - LMT 1924 May 2 4:00 RussiaAsia +04/+05 1992 Jan 19 2:00s 5:00 RussiaAsia +05/+06 2004 Oct 31 2:00s 5:00 - +05 -# Mangghystaū (KZ-MAN) +# Mangghystaū (KZ-47) # Aqtau was not founded until 1963, but it represents an inhabited region, # so include timestamps before 1963. Zone Asia/Aqtau 3:21:04 - LMT 1924 May 2 @@ -2517,7 +2531,7 @@ Zone Asia/Aqtau 3:21:04 - LMT 1924 May 2 5:00 RussiaAsia +05/+06 1994 Sep 25 2:00s 4:00 RussiaAsia +04/+05 2004 Oct 31 2:00s 5:00 - +05 -# Atyraū (KZ-ATY) is like Mangghystaū except it switched from +# Atyraū (KZ-23) is like Mangghystaū except it switched from # +04/+05 to +05/+06 in spring 1999, not fall 1994. Zone Asia/Atyrau 3:27:44 - LMT 1924 May 2 3:00 - +03 1930 Jun 21 @@ -2528,7 +2542,7 @@ Zone Asia/Atyrau 3:27:44 - LMT 1924 May 2 5:00 RussiaAsia +05/+06 1999 Mar 28 2:00s 4:00 RussiaAsia +04/+05 2004 Oct 31 2:00s 5:00 - +05 -# West Kazakhstan (KZ-ZAP) +# West Kazakhstan (KZ-27) # From Paul Eggert (2016-03-18): # The 1989 transition is from USSR act No. 227 (1989-03-14). Zone Asia/Oral 3:25:24 - LMT 1924 May 2 # or Ural'sk @@ -3430,19 +3444,26 @@ Zone Asia/Karachi 4:28:12 - LMT 1907 # ... winter time will begin in Palestine from Saturday 10-28-2023, # 02:00 AM by 60 minutes back. # -# From Paul Eggert (2023-03-22): +# From Heba Hamad (2024-01-25): +# the summer time for the years 2024,2025 will begin in Palestine +# from Saturday at 02:00 AM by 60 minutes forward as shown below: +# year date +# 2024 2024-04-20 +# 2025 2025-04-12 +# +# From Paul Eggert (2024-01-25): # For now, guess that spring and fall transitions will normally # continue to use 2022's rules, that during DST Palestine will switch # to standard time at 02:00 the last Saturday before Ramadan and back -# to DST at 02:00 the first Saturday after Ramadan, and that +# to DST at 02:00 the second Saturday after Ramadan, and that # if the normal spring-forward or fall-back transition occurs during # Ramadan the former is delayed and the latter advanced. # To implement this, I predicted Ramadan-oriented transition dates for -# 2023 through 2086 by running the following program under GNU Emacs 28.2, +# 2026 through 2086 by running the following program under GNU Emacs 29.2, # with the results integrated by hand into the table below. # Predictions after 2086 are approximated without Ramadan. # -# (let ((islamic-year 1444)) +# (let ((islamic-year 1447)) # (require 'cal-islam) # (while (< islamic-year 1510) # (let ((a (calendar-islamic-to-absolute (list 9 1 islamic-year))) @@ -3451,6 +3472,7 @@ Zone Asia/Karachi 4:28:12 - LMT 1907 # (while (/= saturday (mod (setq a (1- a)) 7))) # (while (/= saturday (mod b 7)) # (setq b (1+ b))) +# (setq b (+ 7 b)) # (setq a (calendar-gregorian-from-absolute a)) # (setq b (calendar-gregorian-from-absolute b)) # (insert @@ -3501,84 +3523,84 @@ Rule Palestine 2021 only - Oct 29 1:00 0 - Rule Palestine 2022 only - Mar 27 0:00 1:00 S Rule Palestine 2022 2035 - Oct Sat<=30 2:00 0 - Rule Palestine 2023 only - Apr 29 2:00 1:00 S -Rule Palestine 2024 only - Apr 13 2:00 1:00 S -Rule Palestine 2025 only - Apr 5 2:00 1:00 S +Rule Palestine 2024 only - Apr 20 2:00 1:00 S +Rule Palestine 2025 only - Apr 12 2:00 1:00 S Rule Palestine 2026 2054 - Mar Sat<=30 2:00 1:00 S Rule Palestine 2036 only - Oct 18 2:00 0 - Rule Palestine 2037 only - Oct 10 2:00 0 - Rule Palestine 2038 only - Sep 25 2:00 0 - Rule Palestine 2039 only - Sep 17 2:00 0 - -Rule Palestine 2039 only - Oct 22 2:00 1:00 S -Rule Palestine 2039 2067 - Oct Sat<=30 2:00 0 - Rule Palestine 2040 only - Sep 1 2:00 0 - -Rule Palestine 2040 only - Oct 13 2:00 1:00 S +Rule Palestine 2040 only - Oct 20 2:00 1:00 S +Rule Palestine 2040 2067 - Oct Sat<=30 2:00 0 - Rule Palestine 2041 only - Aug 24 2:00 0 - -Rule Palestine 2041 only - Sep 28 2:00 1:00 S +Rule Palestine 2041 only - Oct 5 2:00 1:00 S Rule Palestine 2042 only - Aug 16 2:00 0 - -Rule Palestine 2042 only - Sep 20 2:00 1:00 S +Rule Palestine 2042 only - Sep 27 2:00 1:00 S Rule Palestine 2043 only - Aug 1 2:00 0 - -Rule Palestine 2043 only - Sep 12 2:00 1:00 S +Rule Palestine 2043 only - Sep 19 2:00 1:00 S Rule Palestine 2044 only - Jul 23 2:00 0 - -Rule Palestine 2044 only - Aug 27 2:00 1:00 S +Rule Palestine 2044 only - Sep 3 2:00 1:00 S Rule Palestine 2045 only - Jul 15 2:00 0 - -Rule Palestine 2045 only - Aug 19 2:00 1:00 S +Rule Palestine 2045 only - Aug 26 2:00 1:00 S Rule Palestine 2046 only - Jun 30 2:00 0 - -Rule Palestine 2046 only - Aug 11 2:00 1:00 S +Rule Palestine 2046 only - Aug 18 2:00 1:00 S Rule Palestine 2047 only - Jun 22 2:00 0 - -Rule Palestine 2047 only - Jul 27 2:00 1:00 S +Rule Palestine 2047 only - Aug 3 2:00 1:00 S Rule Palestine 2048 only - Jun 6 2:00 0 - -Rule Palestine 2048 only - Jul 18 2:00 1:00 S +Rule Palestine 2048 only - Jul 25 2:00 1:00 S Rule Palestine 2049 only - May 29 2:00 0 - -Rule Palestine 2049 only - Jul 3 2:00 1:00 S +Rule Palestine 2049 only - Jul 10 2:00 1:00 S Rule Palestine 2050 only - May 21 2:00 0 - -Rule Palestine 2050 only - Jun 25 2:00 1:00 S +Rule Palestine 2050 only - Jul 2 2:00 1:00 S Rule Palestine 2051 only - May 6 2:00 0 - -Rule Palestine 2051 only - Jun 17 2:00 1:00 S +Rule Palestine 2051 only - Jun 24 2:00 1:00 S Rule Palestine 2052 only - Apr 27 2:00 0 - -Rule Palestine 2052 only - Jun 1 2:00 1:00 S +Rule Palestine 2052 only - Jun 8 2:00 1:00 S Rule Palestine 2053 only - Apr 12 2:00 0 - -Rule Palestine 2053 only - May 24 2:00 1:00 S +Rule Palestine 2053 only - May 31 2:00 1:00 S Rule Palestine 2054 only - Apr 4 2:00 0 - -Rule Palestine 2054 only - May 16 2:00 1:00 S -Rule Palestine 2055 only - May 1 2:00 1:00 S -Rule Palestine 2056 only - Apr 22 2:00 1:00 S -Rule Palestine 2057 only - Apr 7 2:00 1:00 S -Rule Palestine 2058 max - Mar Sat<=30 2:00 1:00 S +Rule Palestine 2054 only - May 23 2:00 1:00 S +Rule Palestine 2055 only - May 8 2:00 1:00 S +Rule Palestine 2056 only - Apr 29 2:00 1:00 S +Rule Palestine 2057 only - Apr 14 2:00 1:00 S +Rule Palestine 2058 only - Apr 6 2:00 1:00 S +Rule Palestine 2059 max - Mar Sat<=30 2:00 1:00 S Rule Palestine 2068 only - Oct 20 2:00 0 - Rule Palestine 2069 only - Oct 12 2:00 0 - Rule Palestine 2070 only - Oct 4 2:00 0 - Rule Palestine 2071 only - Sep 19 2:00 0 - Rule Palestine 2072 only - Sep 10 2:00 0 - -Rule Palestine 2072 only - Oct 15 2:00 1:00 S +Rule Palestine 2072 only - Oct 22 2:00 1:00 S Rule Palestine 2072 max - Oct Sat<=30 2:00 0 - Rule Palestine 2073 only - Sep 2 2:00 0 - -Rule Palestine 2073 only - Oct 7 2:00 1:00 S +Rule Palestine 2073 only - Oct 14 2:00 1:00 S Rule Palestine 2074 only - Aug 18 2:00 0 - -Rule Palestine 2074 only - Sep 29 2:00 1:00 S +Rule Palestine 2074 only - Oct 6 2:00 1:00 S Rule Palestine 2075 only - Aug 10 2:00 0 - -Rule Palestine 2075 only - Sep 14 2:00 1:00 S +Rule Palestine 2075 only - Sep 21 2:00 1:00 S Rule Palestine 2076 only - Jul 25 2:00 0 - -Rule Palestine 2076 only - Sep 5 2:00 1:00 S +Rule Palestine 2076 only - Sep 12 2:00 1:00 S Rule Palestine 2077 only - Jul 17 2:00 0 - -Rule Palestine 2077 only - Aug 28 2:00 1:00 S +Rule Palestine 2077 only - Sep 4 2:00 1:00 S Rule Palestine 2078 only - Jul 9 2:00 0 - -Rule Palestine 2078 only - Aug 13 2:00 1:00 S +Rule Palestine 2078 only - Aug 20 2:00 1:00 S Rule Palestine 2079 only - Jun 24 2:00 0 - -Rule Palestine 2079 only - Aug 5 2:00 1:00 S +Rule Palestine 2079 only - Aug 12 2:00 1:00 S Rule Palestine 2080 only - Jun 15 2:00 0 - -Rule Palestine 2080 only - Jul 20 2:00 1:00 S +Rule Palestine 2080 only - Jul 27 2:00 1:00 S Rule Palestine 2081 only - Jun 7 2:00 0 - -Rule Palestine 2081 only - Jul 12 2:00 1:00 S +Rule Palestine 2081 only - Jul 19 2:00 1:00 S Rule Palestine 2082 only - May 23 2:00 0 - -Rule Palestine 2082 only - Jul 4 2:00 1:00 S +Rule Palestine 2082 only - Jul 11 2:00 1:00 S Rule Palestine 2083 only - May 15 2:00 0 - -Rule Palestine 2083 only - Jun 19 2:00 1:00 S +Rule Palestine 2083 only - Jun 26 2:00 1:00 S Rule Palestine 2084 only - Apr 29 2:00 0 - -Rule Palestine 2084 only - Jun 10 2:00 1:00 S +Rule Palestine 2084 only - Jun 17 2:00 1:00 S Rule Palestine 2085 only - Apr 21 2:00 0 - -Rule Palestine 2085 only - Jun 2 2:00 1:00 S +Rule Palestine 2085 only - Jun 9 2:00 1:00 S Rule Palestine 2086 only - Apr 13 2:00 0 - -Rule Palestine 2086 only - May 18 2:00 1:00 S +Rule Palestine 2086 only - May 25 2:00 1:00 S # Zone NAME STDOFF RULES FORMAT [UNTIL] Zone Asia/Gaza 2:17:52 - LMT 1900 Oct @@ -3606,7 +3628,7 @@ Zone Asia/Hebron 2:20:23 - LMT 1900 Oct # Philippines -# From Paul Eggert (2018-11-18): +# From Paul Eggert (2024-01-21): # The Spanish initially used American (west-of-Greenwich) time. # It is unknown what time Manila kept when the British occupied it from # 1762-10-06 through 1764-04; for now assume it kept American time. @@ -3614,7 +3636,7 @@ Zone Asia/Hebron 2:20:23 - LMT 1900 Oct # Philippines, issued a proclamation announcing that 1844-12-30 was to # be immediately followed by 1845-01-01; see R.H. van Gent's # History of the International Date Line -# https://www.staff.science.uu.nl/~gent0113/idl/idl_philippines.htm +# https://webspace.science.uu.nl/~gent0113/idl/idl_philippines.htm # The rest of the data entries are from Shanks & Pottenger. # From Jesper Nørgaard Welen (2006-04-26): @@ -4041,7 +4063,8 @@ Zone Asia/Tashkent 4:37:11 - LMT 1924 May 2 # The English-language name of Vietnam's most populous city is "Ho Chi Minh # City"; use Ho_Chi_Minh below to avoid a name of more than 14 characters. -# From Paul Eggert (2022-07-27) after a 2014 heads-up from Trần Ngọc Quân: +# From Paul Eggert (2024-01-14) after a 2014 heads-up from Trần Ngọc Quân +# and a 2024-01-14 heads-up from Đoàn Trần Công Danh: # Trần Tiến Bình's authoritative book "Lịch Việt Nam: thế kỷ XX-XXI (1901-2100)" # (Nhà xuất bản Văn Hoá - Thông Tin, Hanoi, 2005), pp 49-50, # is quoted verbatim in: @@ -4071,14 +4094,35 @@ Zone Asia/Tashkent 4:37:11 - LMT 1924 May 2 # # Trần cites the following sources; it's unclear which supplied the info above. # -# Hoàng Xuân Hãn: "Lịch và lịch Việt Nam". Tập san Khoa học Xã hội, -# No. 9, Paris, February 1982. +# Hoàng Xuân Hãn: "Lịch và lịch Việt Nam". Tập san Khoa học Xã hội, +# No. 9, Paris, February 1982. +# +# Lê Thành Lân: "Lịch và niên biểu lịch sử hai mươi thế kỷ (0001-2010)", +# NXB Thống kê, Hanoi, 2000. # -# Lê Thành Lân: "Lịch và niên biểu lịch sử hai mươi thế kỷ (0001-2010)", -# NXB Thống kê, Hanoi, 2000. +# Lê Thành Lân: "Lịch hai thế kỷ (1802-2010) và các lịch vĩnh cửu", +# NXB Thuận Hoá, Huế, 1995. # -# Lê Thành Lân: "Lịch hai thế kỷ (1802-2010) và các lịch vĩnh cửu", -# NXB Thuận Hoá, Huế, 1995. +# Here is the decision for the September 1945 transition: +# Võ Nguyên Giáp, Việt Nam Dân Quốc Công Báo, No. 1 (1945-09-29), page 13 +# http://baochi.nlv.gov.vn/baochi/cgi-bin/baochi?a=d&d=JwvzO19450929.2.5&dliv=none +# It says that on 1945-09-01 at 24:00, Vietnam moved back two hours, to +07. +# It also mentions a 1945-03-29 decree (by a Japanese Goveror-General) +# to set the time zone to +09, but does not say whether that decree +# merely legalized an earlier change to +09. +# +# July 1955 transition: +# Ngô Đình Diệm, Công Báo Việt Nam, No. 92 (1955-07-02), page 1780-1781 +# Ordinance (Dụ) No. 46 (1955-06-25) +# http://ddsnext.crl.edu/titles/32341#?c=0&m=29&s=0&cv=4&r=0&xywh=-89%2C342%2C1724%2C1216 +# It says that on 1955-07-01 at 01:00, South Vietnam moved back 1 hour (to +07). +# +# December 1959 transition: +# Ngô Đình Diệm, Công Báo Việt Nam Cộng Hòa, 1960 part 1 (1960-01-02), page 62 +# Decree (Sắc lệnh) No. 362-TTP (1959-12-30) +# http://ddsnext.crl.edu/titles/32341#?c=0&m=138&s=0&cv=793&r=0&xywh=-54%2C1504%2C1705%2C1202 +# It says that on 1959-12-31 at 23:00, South Vietnam moved forward 1 hour (to +08). + # Zone NAME STDOFF RULES FORMAT [UNTIL] #STDOFF 7:06:30.13 @@ -4086,9 +4130,9 @@ Zone Asia/Ho_Chi_Minh 7:06:30 - LMT 1906 Jul 1 7:06:30 - PLMT 1911 May 1 # Phù Liễn MT 7:00 - +07 1942 Dec 31 23:00 8:00 - +08 1945 Mar 14 23:00 - 9:00 - +09 1945 Sep 2 + 9:00 - +09 1945 Sep 1 24:00 7:00 - +07 1947 Apr 1 - 8:00 - +08 1955 Jul 1 + 8:00 - +08 1955 Jul 1 01:00 7:00 - +07 1959 Dec 31 23:00 8:00 - +08 1975 Jun 13 7:00 - +07 diff --git a/australasia b/australasia index dc98c1e2de17..0e9c2592e4be 100644 --- a/australasia +++ b/australasia @@ -420,11 +420,11 @@ Zone Pacific/Fiji 11:55:44 - LMT 1915 Oct 26 # Suva # French Polynesia # Zone NAME STDOFF RULES FORMAT [UNTIL] -Zone Pacific/Gambier -8:59:48 - LMT 1912 Oct # Rikitea +Zone Pacific/Gambier -8:59:48 - LMT 1912 Oct 1 # Rikitea -9:00 - -09 -Zone Pacific/Marquesas -9:18:00 - LMT 1912 Oct +Zone Pacific/Marquesas -9:18:00 - LMT 1912 Oct 1 -9:30 - -0930 -Zone Pacific/Tahiti -9:58:16 - LMT 1912 Oct # Papeete +Zone Pacific/Tahiti -9:58:16 - LMT 1912 Oct 1 # Papeete -10:00 - -10 # Clipperton (near North America) is administered from French Polynesia; # it is uninhabited. @@ -802,7 +802,7 @@ Zone Pacific/Apia 12:33:04 - LMT 1892 Jul 5 # Solomon Is # excludes Bougainville, for which see Papua New Guinea # Zone NAME STDOFF RULES FORMAT [UNTIL] -Zone Pacific/Guadalcanal 10:39:48 - LMT 1912 Oct # Honiara +Zone Pacific/Guadalcanal 10:39:48 - LMT 1912 Oct 1 # Honiara 11:00 - +11 # Tokelau @@ -963,6 +963,10 @@ Zone Pacific/Efate 11:13:16 - LMT 1912 Jan 13 # Vila # Milne J. Civil time. Geogr J. 1899 Feb;13(2):173-94. # https://www.jstor.org/stable/1774359 # +# For the 1911/1912 establishment of standard time in French possessions, see: +# Société Française de Physique, Recueil de constantes physiques (1913), +# page 752, 18b. +# # A reliable and entertaining source about time zones is # Derek Howse, Greenwich time and longitude, Philip Wilson Publishers (1997). # @@ -2039,7 +2043,7 @@ Zone Pacific/Efate 11:13:16 - LMT 1912 Jan 13 # Vila # ordaining - by a masterpiece of diplomatic flattery - that # the Fourth of July should be celebrated twice in that year." # This happened in 1892, according to the Evening News (Sydney) of 1892-07-20. -# https://www.staff.science.uu.nl/~gent0113/idl/idl.htm +# https://webspace.science.uu.nl/~gent0113/idl/idl_alaska_samoa.htm # Although Shanks & Pottenger says they both switched to UT -11:30 # in 1911, and to -11 in 1950. many earlier sources give -11 diff --git a/checknow.awk b/checknow.awk index d722c03fd689..57ff3c02e789 100644 --- a/checknow.awk +++ b/checknow.awk @@ -45,7 +45,7 @@ END { for (zone in zone_data) { data = zone_data[zone] if (!zonenow[data]) { - printf "checknow.tab should have one of:%s\n", zones[data] + printf "zonenow.tab should have one of:%s\n", zones[data] zonenow[data] = zone # This suppresses duplicate diagnostics. status = 1 } @@ -5,7 +5,7 @@ # These entries are for uses not otherwise covered by the tz database. # Their main practical use is for platforms like Android that lack -# support for POSIX-style TZ strings. On such platforms these entries +# support for POSIX.1-2017-style TZ strings. On such platforms these entries # can be useful if the timezone database is wrong or if a ship or # aircraft at sea is not in a timezone. @@ -990,9 +990,34 @@ Zone Europe/Sofia 1:33:16 - LMT 1880 # Czech Republic (Czechia) # Slovakia # -# From Paul Eggert (2018-04-15): -# The source for Czech data is: Kdy začíná a končí letní čas. 2018-04-15. +# From Ivan Benovic (2024-01-30): +# https://www.slov-lex.sk/pravne-predpisy/SK/ZZ/1946/54/ +# (This is an official link to the Czechoslovak Summer Time Act of +# March 8, 1946 that authorizes the Czechoslovak government to set the +# exact dates of change to summer time and back to Central European Time. +# The act also implicitly confirms Central European Time as the +# official time zone of Czechoslovakia and currently remains in force +# in both the Czech Republic and Slovakia.) +# https://www.psp.cz/eknih/1945pns/tisky/t0216_00.htm +# (This is a link to the original legislative proposal dating back to +# February 22, 1946. The accompanying memorandum to the proposal says +# that an advisory committee on European railroad transportation that +# met in Brussels in October 1945 decided that the change of time +# should be carried out in all participating countries in a strictly +# coordinated manner....) +# +# From Paul Eggert (2024-01-30): +# The source for Czech data is: Kdy začíná a končí letní čas. # https://kalendar.beda.cz/kdy-zacina-a-konci-letni-cas +# Its main text disagrees with its quoted sources only in 1918, +# where the main text says spring and autumn transitions +# occurred at 02:00 and 03:00 respectively (as usual), +# whereas the 1918 source "Oznámení o zavedení letního času v roce 1918" +# says transitions were at 01:00 and 02:00 respectively. +# As the 1918 source appears to be a humorous piece, and it is +# unlikely that Prague would have disagreed with its neighbors by an hour, +# go with the main text for now. +# # We know of no English-language name for historical Czech winter time; # abbreviate it as "GMT", as it happened to be GMT. # diff --git a/leap-seconds.list b/leap-seconds.list index 3fe9a1210e3c..e52effc257b2 100644 --- a/leap-seconds.list +++ b/leap-seconds.list @@ -1,255 +1,120 @@ +# ATOMIC TIME. +# The Coordinated Universal Time (UTC) is the reference time scale derived +# from The "Temps Atomique International" (TAI) calculated by the Bureau +# International des Poids et Mesures (BIPM) using a worldwide network of atomic +# clocks. UTC differs from TAI by an integer number of seconds; it is the basis +# of all activities in the world. # -# In the following text, the symbol '#' introduces -# a comment, which continues from that symbol until -# the end of the line. A plain comment line has a -# whitespace character following the comment indicator. -# There are also special comment lines defined below. -# A special comment will always have a non-whitespace -# character in column 2. -# -# A blank line should be ignored. -# -# The following table shows the corrections that must -# be applied to compute International Atomic Time (TAI) -# from the Coordinated Universal Time (UTC) values that -# are transmitted by almost all time services. -# -# The first column shows an epoch as a number of seconds -# since 1 January 1900, 00:00:00 (1900.0 is also used to -# indicate the same epoch.) Both of these time stamp formats -# ignore the complexities of the time scales that were -# used before the current definition of UTC at the start -# of 1972. (See note 3 below.) -# The second column shows the number of seconds that -# must be added to UTC to compute TAI for any timestamp -# at or after that epoch. The value on each line is -# valid from the indicated initial instant until the -# epoch given on the next one or indefinitely into the -# future if there is no next line. -# (The comment on each line shows the representation of -# the corresponding initial epoch in the usual -# day-month-year format. The epoch always begins at -# 00:00:00 UTC on the indicated day. See Note 5 below.) -# -# Important notes: -# -# 1. Coordinated Universal Time (UTC) is often referred to -# as Greenwich Mean Time (GMT). The GMT time scale is no -# longer used, and the use of GMT to designate UTC is -# discouraged. -# -# 2. The UTC time scale is realized by many national -# laboratories and timing centers. Each laboratory -# identifies its realization with its name: Thus -# UTC(NIST), UTC(USNO), etc. The differences among -# these different realizations are typically on the -# order of a few nanoseconds (i.e., 0.000 000 00x s) -# and can be ignored for many purposes. These differences -# are tabulated in Circular T, which is published monthly -# by the International Bureau of Weights and Measures -# (BIPM). See www.bipm.org for more information. -# -# 3. The current definition of the relationship between UTC -# and TAI dates from 1 January 1972. A number of different -# time scales were in use before that epoch, and it can be -# quite difficult to compute precise timestamps and time -# intervals in those "prehistoric" days. For more information, -# consult: -# -# The Explanatory Supplement to the Astronomical -# Ephemeris. -# or -# Terry Quinn, "The BIPM and the Accurate Measurement -# of Time," Proc. of the IEEE, Vol. 79, pp. 894-905, -# July, 1991. <http://dx.doi.org/10.1109/5.84965> -# reprinted in: -# Christine Hackman and Donald B Sullivan (eds.) -# Time and Frequency Measurement -# American Association of Physics Teachers (1996) -# <http://tf.nist.gov/general/pdf/1168.pdf>, pp. 75-86 -# -# 4. The decision to insert a leap second into UTC is currently -# the responsibility of the International Earth Rotation and -# Reference Systems Service. (The name was changed from the -# International Earth Rotation Service, but the acronym IERS -# is still used.) -# -# Leap seconds are announced by the IERS in its Bulletin C. -# -# See www.iers.org for more details. -# -# Every national laboratory and timing center uses the -# data from the BIPM and the IERS to construct UTC(lab), -# their local realization of UTC. -# -# Although the definition also includes the possibility -# of dropping seconds ("negative" leap seconds), this has -# never been done and is unlikely to be necessary in the -# foreseeable future. -# -# 5. If your system keeps time as the number of seconds since -# some epoch (e.g., NTP timestamps), then the algorithm for -# assigning a UTC time stamp to an event that happens during a positive -# leap second is not well defined. The official name of that leap -# second is 23:59:60, but there is no way of representing that time -# in these systems. -# Many systems of this type effectively stop the system clock for -# one second during the leap second and use a time that is equivalent -# to 23:59:59 UTC twice. For these systems, the corresponding TAI -# timestamp would be obtained by advancing to the next entry in the -# following table when the time equivalent to 23:59:59 UTC -# is used for the second time. Thus the leap second which -# occurred on 30 June 1972 at 23:59:59 UTC would have TAI -# timestamps computed as follows: -# -# ... -# 30 June 1972 23:59:59 (2287785599, first time): TAI= UTC + 10 seconds -# 30 June 1972 23:59:60 (2287785599,second time): TAI= UTC + 11 seconds -# 1 July 1972 00:00:00 (2287785600) TAI= UTC + 11 seconds -# ... -# -# If your system realizes the leap second by repeating 00:00:00 UTC twice -# (this is possible but not usual), then the advance to the next entry -# in the table must occur the second time that a time equivalent to -# 00:00:00 UTC is used. Thus, using the same example as above: -# -# ... -# 30 June 1972 23:59:59 (2287785599): TAI= UTC + 10 seconds -# 30 June 1972 23:59:60 (2287785600, first time): TAI= UTC + 10 seconds -# 1 July 1972 00:00:00 (2287785600,second time): TAI= UTC + 11 seconds -# ... -# -# in both cases the use of timestamps based on TAI produces a smooth -# time scale with no discontinuity in the time interval. However, -# although the long-term behavior of the time scale is correct in both -# methods, the second method is technically not correct because it adds -# the extra second to the wrong day. -# -# This complexity would not be needed for negative leap seconds (if they -# are ever used). The UTC time would skip 23:59:59 and advance from -# 23:59:58 to 00:00:00 in that case. The TAI offset would decrease by -# 1 second at the same instant. This is a much easier situation to deal -# with, since the difficulty of unambiguously representing the epoch -# during the leap second does not arise. -# -# Some systems implement leap seconds by amortizing the leap second -# over the last few minutes of the day. The frequency of the local -# clock is decreased (or increased) to realize the positive (or -# negative) leap second. This method removes the time step described -# above. Although the long-term behavior of the time scale is correct -# in this case, this method introduces an error during the adjustment -# period both in time and in frequency with respect to the official -# definition of UTC. -# -# Questions or comments to: -# Judah Levine -# Time and Frequency Division -# NIST -# Boulder, Colorado -# Judah.Levine@nist.gov -# -# Last Update of leap second values: 8 July 2016 -# -# The following line shows this last update date in NTP timestamp -# format. This is the date on which the most recent change to -# the leap second data was added to the file. This line can -# be identified by the unique pair of characters in the first two -# columns as shown below. -# -#$ 3676924800 -# -# The NTP timestamps are in units of seconds since the NTP epoch, -# which is 1 January 1900, 00:00:00. The Modified Julian Day number -# corresponding to the NTP time stamp, X, can be computed as -# -# X/86400 + 15020 -# -# where the first term converts seconds to days and the second -# term adds the MJD corresponding to the time origin defined above. -# The integer portion of the result is the integer MJD for that -# day, and any remainder is the time of day, expressed as the -# fraction of the day since 0 hours UTC. The conversion from day -# fraction to seconds or to hours, minutes, and seconds may involve -# rounding or truncation, depending on the method used in the -# computation. -# -# The data in this file will be updated periodically as new leap -# seconds are announced. In addition to being entered on the line -# above, the update time (in NTP format) will be added to the basic -# file name leap-seconds to form the name leap-seconds.<NTP TIME>. -# In addition, the generic name leap-seconds.list will always point to -# the most recent version of the file. -# -# This update procedure will be performed only when a new leap second -# is announced. -# -# The following entry specifies the expiration date of the data -# in this file in units of seconds since the origin at the instant -# 1 January 1900, 00:00:00. This expiration date will be changed -# at least twice per year whether or not a new leap second is -# announced. These semi-annual changes will be made no later -# than 1 June and 1 December of each year to indicate what -# action (if any) is to be taken on 30 June and 31 December, -# respectively. (These are the customary effective dates for new -# leap seconds.) This expiration date will be identified by a -# unique pair of characters in columns 1 and 2 as shown below. -# In the unlikely event that a leap second is announced with an -# effective date other than 30 June or 31 December, then this -# file will be edited to include that leap second as soon as it is -# announced or at least one month before the effective date -# (whichever is later). -# If an announcement by the IERS specifies that no leap second is -# scheduled, then only the expiration date of the file will -# be advanced to show that the information in the file is still -# current -- the update time stamp, the data and the name of the file -# will not change. -# -# Updated through IERS Bulletin C66 -# File expires on: 28 June 2024 -# -#@ 3928521600 -# -2272060800 10 # 1 Jan 1972 -2287785600 11 # 1 Jul 1972 -2303683200 12 # 1 Jan 1973 -2335219200 13 # 1 Jan 1974 -2366755200 14 # 1 Jan 1975 -2398291200 15 # 1 Jan 1976 -2429913600 16 # 1 Jan 1977 -2461449600 17 # 1 Jan 1978 -2492985600 18 # 1 Jan 1979 -2524521600 19 # 1 Jan 1980 -2571782400 20 # 1 Jul 1981 -2603318400 21 # 1 Jul 1982 -2634854400 22 # 1 Jul 1983 -2698012800 23 # 1 Jul 1985 -2776982400 24 # 1 Jan 1988 -2840140800 25 # 1 Jan 1990 -2871676800 26 # 1 Jan 1991 -2918937600 27 # 1 Jul 1992 -2950473600 28 # 1 Jul 1993 -2982009600 29 # 1 Jul 1994 -3029443200 30 # 1 Jan 1996 -3076704000 31 # 1 Jul 1997 -3124137600 32 # 1 Jan 1999 -3345062400 33 # 1 Jan 2006 -3439756800 34 # 1 Jan 2009 -3550089600 35 # 1 Jul 2012 -3644697600 36 # 1 Jul 2015 -3692217600 37 # 1 Jan 2017 -# -# the following special comment contains the -# hash value of the data in this file computed -# use the secure hash algorithm as specified -# by FIPS 180-1. See the files in ~/pub/sha for -# the details of how this hash value is -# computed. Note that the hash computation -# ignores comments and whitespace characters -# in data lines. It includes the NTP values -# of both the last modification time and the -# expiration time of the file, but not the -# white space on those lines. -# the hash line is also ignored in the -# computation. -# -#h 16edd0f0 3666784f 37db6bdd e74ced87 59af48f1 +# +# ASTRONOMICAL TIME (UT1) is the time scale based on the rate of rotation of the earth. +# It is now mainly derived from Very Long Baseline Interferometry (VLBI). The various +# irregular fluctuations progressively detected in the rotation rate of the Earth lead +# in 1972 to the replacement of UT1 by UTC as the reference time scale. +# +# +# LEAP SECOND +# Atomic clocks are more stable than the rate of the earth rotation since the latter +# undergoes a full range of geophysical perturbations at various time scales: lunisolar +# and core-mantle torques, atmospheric and oceanic effetcs, etc. +# Leap seconds are needed to keep the two time scales in agreement, i.e. UT1-UTC smaller +# than 0.9 second. Therefore, when necessary a "leap second" is applied to UTC. +# Since the adoption of this system in 1972 it has been necessary to add a number of seconds to UTC, +# firstly due to the initial choice of the value of the second (1/86400 mean solar day of +# the year 1820) and secondly to the general slowing down of the Earth's rotation. It is +# theorically possible to have a negative leap second (a second removed from UTC), but so far, +# all leap seconds have been positive (a second has been added to UTC). Based on what we know about +# the earth's rotation, it is unlikely that we will ever have a negative leap second. +# +# +# HISTORY +# The first leap second was added on June 30, 1972. Until yhe year 2000, it was necessary in average to add a +# leap second at a rate of 1 to 2 years. Since the year 2000 leap seconds are introduced with an +# average interval of 3 to 4 years due to the acceleration of the Earth rotation speed. +# +# +# RESPONSABILITY OF THE DECISION TO INTRODUCE A LEAP SECOND IN UTC +# The decision to introduce a leap second in UTC is the responsibility of the Earth Orientation Center of +# the International Earth Rotation and reference System Service (IERS). This center is located at Paris +# Observatory. According to international agreements, leap seconds should only be scheduled for certain dates: +# first preference is given to the end of December and June, and second preference at the end of March +# and September. Since the introduction of leap seconds in 1972, only dates in June and December were used. +# +# Questions or comments to: +# Christian Bizouard: christian.bizouard@obspm.fr +# Earth orientation Center of the IERS +# Paris Observatory, France +# +# +# +# COPYRIGHT STATUS OF THIS FILE +# This file is in the public domain. +# +# +# VALIDITY OF THE FILE +# It is important to express the validity of the file. These next two dates are +# given in units of seconds since 1900.0. +# +# 1) Last update of the file. +# +# Updated through IERS Bulletin C (https://hpiers.obspm.fr/iers/bul/bulc/bulletinc.dat) +# +# The following line shows the last update of this file in NTP timestamp: +# +#$ 3913697179 +# +# 2) Expiration date of the file given on a semi-annual basis: last June or last December +# +# File expires on 28 December 2024 +# +# Expire date in NTP timestamp: +# +#@ 3944332800 +# +# +# LIST OF LEAP SECONDS +# NTP timestamp (X parameter) is the number of seconds since 1900.0 +# +# MJD: The Modified Julian Day number. MJD = X/86400 + 15020 +# +# DTAI: The difference DTAI= TAI-UTC in units of seconds +# It is the quantity to add to UTC to get the time in TAI +# +# Day Month Year : epoch in clear +# +#NTP Time DTAI Day Month Year +# +2272060800 10 # 1 Jan 1972 +2287785600 11 # 1 Jul 1972 +2303683200 12 # 1 Jan 1973 +2335219200 13 # 1 Jan 1974 +2366755200 14 # 1 Jan 1975 +2398291200 15 # 1 Jan 1976 +2429913600 16 # 1 Jan 1977 +2461449600 17 # 1 Jan 1978 +2492985600 18 # 1 Jan 1979 +2524521600 19 # 1 Jan 1980 +2571782400 20 # 1 Jul 1981 +2603318400 21 # 1 Jul 1982 +2634854400 22 # 1 Jul 1983 +2698012800 23 # 1 Jul 1985 +2776982400 24 # 1 Jan 1988 +2840140800 25 # 1 Jan 1990 +2871676800 26 # 1 Jan 1991 +2918937600 27 # 1 Jul 1992 +2950473600 28 # 1 Jul 1993 +2982009600 29 # 1 Jul 1994 +3029443200 30 # 1 Jan 1996 +3076704000 31 # 1 Jul 1997 +3124137600 32 # 1 Jan 1999 +3345062400 33 # 1 Jan 2006 +3439756800 34 # 1 Jan 2009 +3550089600 35 # 1 Jul 2012 +3644697600 36 # 1 Jul 2015 +3692217600 37 # 1 Jan 2017 +# +# A hash code has been generated to be able to verify the integrity +# of this file. For more information about using this hash code, +# please see the readme file in the 'source' directory : +# https://hpiers.obspm.fr/iers/bul/bulc/ntp/sources/README +# +#h 9dac5845 8acd32c0 2947d462 daf4a943 f58d9391 diff --git a/leapseconds b/leapseconds index 8938c763e0ed..ce150bfe0dca 100644 --- a/leapseconds +++ b/leapseconds @@ -3,13 +3,10 @@ # This file is in the public domain. # This file is generated automatically from the data in the public-domain -# NIST format leap-seconds.list file, which can be copied from -# <ftp://ftp.nist.gov/pub/time/leap-seconds.list> -# or <ftp://ftp.boulder.nist.gov/pub/time/leap-seconds.list>. -# The NIST file is used instead of its IERS upstream counterpart +# NIST/IERS format leap-seconds.list file, which can be copied from # <https://hpiers.obspm.fr/iers/bul/bulc/ntp/leap-seconds.list> -# because under US law the NIST file is public domain -# whereas the IERS file's copyright and license status is unclear. +# or, in a variant with different comments, from +# <ftp://ftp.boulder.nist.gov/pub/time/leap-seconds.list>. # For more about leap-seconds.list, please see # The NTP Timescale and Leap Seconds # <https://www.eecis.udel.edu/~mills/leap.html>. @@ -72,11 +69,11 @@ Leap 2016 Dec 31 23:59:60 + S # Any additional leap seconds will come after this. # This Expires line is commented out for now, # so that pre-2020a zic implementations do not reject this file. -#Expires 2024 Jun 28 00:00:00 +#Expires 2024 Dec 28 00:00:00 # POSIX timestamps for the data in this file: -#updated 1467936000 (2016-07-08 00:00:00 UTC) -#expires 1719532800 (2024-06-28 00:00:00 UTC) +#updated 1704708379 (2024-01-08 10:06:19 UTC) +#expires 1735344000 (2024-12-28 00:00:00 UTC) -# Updated through IERS Bulletin C66 -# File expires on: 28 June 2024 +# Updated through IERS Bulletin C (https://hpiers.obspm.fr/iers/bul/bulc/bulletinc.dat) +# File expires on 28 December 2024 diff --git a/leapseconds.awk b/leapseconds.awk index 7d2556bf1ca7..15e85012bf95 100644 --- a/leapseconds.awk +++ b/leapseconds.awk @@ -1,4 +1,4 @@ -# Generate zic format 'leapseconds' from NIST format 'leap-seconds.list'. +# Generate zic format 'leapseconds' from NIST/IERS format 'leap-seconds.list'. # This file is in the public domain. @@ -21,13 +21,10 @@ BEGIN { print "# This file is in the public domain." print "" print "# This file is generated automatically from the data in the public-domain" - print "# NIST format leap-seconds.list file, which can be copied from" - print "# <ftp://ftp.nist.gov/pub/time/leap-seconds.list>" - print "# or <ftp://ftp.boulder.nist.gov/pub/time/leap-seconds.list>." - print "# The NIST file is used instead of its IERS upstream counterpart" + print "# NIST/IERS format leap-seconds.list file, which can be copied from" print "# <https://hpiers.obspm.fr/iers/bul/bulc/ntp/leap-seconds.list>" - print "# because under US law the NIST file is public domain" - print "# whereas the IERS file's copyright and license status is unclear." + print "# or, in a variant with different comments, from" + print "# <ftp://ftp.boulder.nist.gov/pub/time/leap-seconds.list>." print "# For more about leap-seconds.list, please see" print "# The NTP Timescale and Leap Seconds" print "# <https://www.eecis.udel.edu/~mills/leap.html>." diff --git a/northamerica b/northamerica index 8ac106ab2229..bbfce49ba193 100644 --- a/northamerica +++ b/northamerica @@ -1268,6 +1268,10 @@ Zone America/Menominee -5:50:27 - LMT 1885 Sep 18 12:00 # <http://cs.ucla.edu/~eggert/The-Waste-of-Daylight-19th.pdf> # [PDF] (1914-03) # +# For the 1911/1912 establishment of standard time in French possessions, see: +# Société Française de Physique, Recueil de constantes physiques (1913), +# page 752, 18b. +# # See the 'europe' file for Greenland. # Canada @@ -1354,7 +1358,7 @@ Zone America/Menominee -5:50:27 - LMT 1885 Sep 18 12:00 # From Paul Eggert (2014-10-18): # H. David Matthews and Mary Vincent's map # "It's about TIME", _Canadian Geographic_ (September-October 1998) -# http://www.canadiangeographic.ca/Magazine/SO98/alacarte.asp +# https://web.archive.org/web/19990827055050/https://canadiangeographic.ca/SO98/geomap.htm # contains detailed boundaries for regions observing nonstandard # time and daylight saving time arrangements in Canada circa 1998. # @@ -1642,6 +1646,15 @@ Zone America/Moncton -4:19:08 - LMT 1883 Dec 9 # Some cities in the United States have pushed the deadline back # three weeks and will change over from daylight saving in October. +# From Chris Walton (2024-01-09): +# The [Toronto] changes in 1947, 1948, and 1949 took place at 2:00 a.m. local +# time instead of midnight.... Toronto Daily Star - ... +# April 2, 1947 - Page 39 ... April 7, 1948 - Page 13 ... +# April 2, 1949 - Page 1 ... April 7, 1949 - Page 24 ... +# November 25, 1949 - Page 52 ... April 21, 1950 - Page 14 ... +# September 19, 1950 - Page 46 ... September 20, 1950 - Page 3 ... +# November 24, 1950 - Page 21 + # From Arthur David Olson (2010-07-17): # # "Standard Time and Time Zones in Canada" appeared in @@ -1703,13 +1716,9 @@ Rule Toronto 1927 1937 - Sep Sun>=25 2:00 0 S Rule Toronto 1928 1937 - Apr Sun>=25 2:00 1:00 D Rule Toronto 1938 1940 - Apr lastSun 2:00 1:00 D Rule Toronto 1938 1939 - Sep lastSun 2:00 0 S -Rule Toronto 1945 1946 - Sep lastSun 2:00 0 S -Rule Toronto 1946 only - Apr lastSun 2:00 1:00 D -Rule Toronto 1947 1949 - Apr lastSun 0:00 1:00 D -Rule Toronto 1947 1948 - Sep lastSun 0:00 0 S -Rule Toronto 1949 only - Nov lastSun 0:00 0 S -Rule Toronto 1950 1973 - Apr lastSun 2:00 1:00 D -Rule Toronto 1950 only - Nov lastSun 2:00 0 S +Rule Toronto 1945 1948 - Sep lastSun 2:00 0 S +Rule Toronto 1946 1973 - Apr lastSun 2:00 1:00 D +Rule Toronto 1949 1950 - Nov lastSun 2:00 0 S Rule Toronto 1951 1956 - Sep lastSun 2:00 0 S # Shanks & Pottenger say Toronto ended DST a week early in 1971, # namely on 1971-10-24, but Mark Brader wrote (2003-05-31) that this @@ -3432,7 +3441,7 @@ Zone America/Jamaica -5:07:10 - LMT 1890 # Kingston # Martinique # Zone NAME STDOFF RULES FORMAT [UNTIL] Zone America/Martinique -4:04:20 - LMT 1890 # Fort-de-France - -4:04:20 - FFMT 1911 May # Fort-de-France MT + -4:04:20 - FFMT 1911 May 1 # Fort-de-France MT -4:00 - AST 1980 Apr 6 -4:00 1:00 ADT 1980 Sep 28 -4:00 - AST @@ -3539,7 +3548,7 @@ Zone America/Puerto_Rico -4:24:25 - LMT 1899 Mar 28 12:00 # San Juan # St Pierre and Miquelon # There are too many St Pierres elsewhere, so we'll use 'Miquelon'. # Zone NAME STDOFF RULES FORMAT [UNTIL] -Zone America/Miquelon -3:44:40 - LMT 1911 May 15 # St Pierre +Zone America/Miquelon -3:44:40 - LMT 1911 Jun 15 # St Pierre -4:00 - AST 1980 May -3:00 - -03 1987 -3:00 Canada -03/-02 diff --git a/southamerica b/southamerica index 19c7e4566cd4..344e67f38f4c 100644 --- a/southamerica +++ b/southamerica @@ -1570,8 +1570,11 @@ Zone Atlantic/Stanley -3:51:24 - LMT 1890 -3:00 - -03 # French Guiana +# For the 1911/1912 establishment of standard time in French possessions, see: +# Société Française de Physique, Recueil de constantes physiques (1913), +# page 752, 18b. # Zone NAME STDOFF RULES FORMAT [UNTIL] -Zone America/Cayenne -3:29:20 - LMT 1911 Jul +Zone America/Cayenne -3:29:20 - LMT 1911 Jul 1 -4:00 - -04 1967 Oct -3:00 - -03 diff --git a/theory.html b/theory.html index 369c75433ff2..516d2a525111 100644 --- a/theory.html +++ b/theory.html @@ -95,7 +95,7 @@ Group Base Specifications Issue 7</a>, IEEE Std 1003.1-2017, 2018 Edition. Because the database's scope encompasses real-world changes to civil timekeeping, its model for describing time is more complex than the -standard and daylight saving times supported by POSIX. +standard and daylight saving times supported by POSIX.1-2017. A <code><abbr>tz</abbr></code> timezone corresponds to a ruleset that can have more than two changes per year, these changes need not merely flip back and forth between two alternatives, and the rules themselves @@ -187,7 +187,7 @@ in decreasing order of importance: href="https://en.wikipedia.org/wiki/ASCII">ASCII</a> letters, '<code>.</code>', '<code>-</code>' and '<code>_</code>'. Do not use digits, as that might create an ambiguity with <a - href="https://pubs.opengroup.org/onlinepubs/9699919799/basedefs/V1_chap08.html#tag_08_03">POSIX + href="https://pubs.opengroup.org/onlinepubs/9699919799/basedefs/V1_chap08.html#tag_08_03">POSIX.1-2017 <code>TZ</code> strings</a>. A file name component must not exceed 14 characters or start with '<code>-</code>'. @@ -362,6 +362,11 @@ The backward-compatibility file <code>zone.tab</code> is similar but conforms to the older-version guidelines related to <abbr>ISO</abbr> 3166-1; it lists only one country code per entry and unlike <code>zone1970.tab</code> it can list names defined in <code>backward</code>. +Applications that process only timestamps from now on can instead use the file +<code>zonenow.tab</code>, which partitions the world more coarsely, +into regions where clocks agree now and in the predicted future; +this file is smaller and simpler than <code>zone1970.tab</code> +and <code>zone.tab</code>. </p> <p> @@ -373,7 +378,7 @@ nowadays distributions typically use it and no great weight should be attached to whether a link 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 POSIX-style <code>TZ</code> strings; +on platforms that do not support POSIX.1-2017-style <code>TZ</code> strings; no other source file other than <code>backward</code> contains links to its zones. One of <code>etcetera</code>'s names is <code>Etc/UTC</code>, @@ -421,7 +426,7 @@ in decreasing order of importance: expression <code>[-+[:alnum:]]{3,6}</code> should match the abbreviation. This guarantees that all abbreviations could have been specified by a - POSIX <code>TZ</code> string. + POSIX.1-2017 <code>TZ</code> string. </p> </li> <li> @@ -765,12 +770,12 @@ href="https://www.dissentmagazine.org/blog/booked-a-global-history-of-time-vanes calendar with 24-hour days. These divergences range from relatively minor, such as Japanese bars giving times like "24:30" for the wee hours of the morning, to more-significant differences such as <a - href="https://www.pri.org/stories/2015-01-30/if-you-have-meeting-ethiopia-you-better-double-check-time">the + href="https://theworld.org/stories/2015-01-30/if-you-have-meeting-ethiopia-you-better-double-check-time">the east African practice of starting the day at dawn</a>, renumbering the Western 06:00 to be 12:00. These practices are largely outside the scope of the <code><abbr>tz</abbr></code> code and data, which provide only limited support for date and time localization - such as that required by POSIX. + such as that required by POSIX.1-2017. If <abbr>DST</abbr> is not used a different time zone can often do the trick; for example, in Kenya a <code>TZ</code> setting like <code><-03>3</code> or <code>America/Cayenne</code> starts @@ -867,23 +872,23 @@ input is occasionally extended, and a platform may still be shipping an older <code>zic</code>. </p> -<h3 id="POSIX">POSIX properties and limitations</h3> +<h3 id="POSIX">POSIX.1-2017 properties and limitations</h3> <ul> <li> <p> - In POSIX, time display in a process is controlled by the + In POSIX.1-2017, time display in a process is controlled by the environment variable <code>TZ</code>. - Unfortunately, the POSIX + Unfortunately, the POSIX.1-2017 <code>TZ</code> string takes a form that is hard to describe and is error-prone in practice. - Also, POSIX <code>TZ</code> strings cannot deal with daylight + Also, POSIX.1-2017 <code>TZ</code> strings cannot deal with daylight saving time rules not based on the Gregorian calendar (as in Morocco), or with situations where more than two time zone abbreviations or <abbr>UT</abbr> offsets are used in an area. </p> <p> - The POSIX <code>TZ</code> string takes the following form: + The POSIX.1-2017 <code>TZ</code> string takes the following form: </p> <p> @@ -950,7 +955,7 @@ an older <code>zic</code>. </dl> <p> - Here is an example POSIX <code>TZ</code> string for New + Here is an example POSIX.1-2017 <code>TZ</code> string for New Zealand after 2007. It says that standard time (<abbr>NZST</abbr>) is 12 hours ahead of <abbr>UT</abbr>, and that daylight saving time @@ -961,7 +966,7 @@ an older <code>zic</code>. <pre><code>TZ='NZST-12NZDT,M9.5.0,M4.1.0/3'</code></pre> <p> - This POSIX <code>TZ</code> string is hard to remember, and + This POSIX.1-2017 <code>TZ</code> string is hard to remember, and mishandles some timestamps before 2008. With this package you can use this instead: </p> @@ -999,7 +1004,7 @@ an older <code>zic</code>. limit phone calls to off-peak hours. </li> <li> - POSIX provides no convenient and efficient way to determine + POSIX.1-2017 provides no convenient and efficient way to determine the <abbr>UT</abbr> offset and time zone abbreviation of arbitrary timestamps, particularly for timezones that do not fit into the POSIX model. @@ -1026,14 +1031,14 @@ an older <code>zic</code>. </li> </ul> -<h3 id="POSIX-extensions">Extensions to POSIX in the +<h3 id="POSIX-extensions">Extensions to POSIX.1-2017 in the <code><abbr>tz</abbr></code> code</h3> <ul> <li> <p> The <code>TZ</code> environment variable is used in generating the name of a file from which time-related information is read - (or is interpreted à la POSIX); <code>TZ</code> is no longer + (or is interpreted à la POSIX.1-2017); <code>TZ</code> is no longer constrained to be a string containing abbreviations and numeric data as described <a href="#POSIX">above</a>. The file's format is <dfn><abbr>TZif</abbr></dfn>, @@ -1 +1 @@ -2023d +2024a diff --git a/zishrink.awk b/zishrink.awk index 66968e8648e0..c98dc6ae786d 100644 --- a/zishrink.awk +++ b/zishrink.awk @@ -162,7 +162,7 @@ function make_line(n, field, \ # Process the input line LINE and save it for later output. function process_input_line(line, \ - f, field, end, i, n, r, startdef, \ + f, field, end, n, outline, r, \ linkline, ruleline, zoneline) { # Remove comments, normalize spaces, and append a space to each line. @@ -199,8 +199,10 @@ function process_input_line(line, \ } # Abbreviate "max", "min", "only" and month names. - gsub(/ max /, " ma ", line) - gsub(/ min /, " mi ", line) + # Although "max" and "min" can both be abbreviated to just "m", + # the longer forms "ma" and "mi" are needed with zic 2023d and earlier. + gsub(/ max /, dataform == "vanguard" ? " m " : " ma ", line) + gsub(/ min /, dataform == "vanguard" ? " m " : " mi ", line) gsub(/ only /, " o ", line) gsub(/ Jan /, " Ja ", line) gsub(/ Feb /, " F ", line) @@ -234,66 +236,96 @@ function process_input_line(line, \ rule_used[r] = 1 } - # If this zone supersedes an earlier one, delete the earlier one - # from the saved output lines. - startdef = "" if (zoneline) zonename = startdef = field[2] else if (linkline) zonename = startdef = field[3] else if (ruleline) zonename = "" - if (startdef) { - i = zonedef[startdef] - if (i) { - do - output_line[i - 1] = "" - while (output_line[i++] ~ /^[-+0-9]/); - } - } - zonedef[zonename] = nout + 1 - # Save the line for later output. - output_line[nout++] = make_line(n, field) + # Save the information for later output. + outline = make_line(n, field) + if (ruleline) + rule_output_line[nrule_out++] = outline + else if (linkline) { + # In vanguard format with Gawk, links are output sorted by destination. + if (dataform == "vanguard" && PROCINFO["version"]) + linkdef[zonename] = field[2] + else + link_output_line[nlink_out++] = outline + }else + zonedef[zonename] = (zoneline ? "" : zonedef[zonename] "\n") outline } function omit_unused_rules( \ i, field) { - for (i = 0; i < nout; i++) { - split(output_line[i], field) - if (field[1] == "R" && !rule_used[field[2]]) { - output_line[i] = "" - } + for (i = 0; i < nrule_out; i++) { + split(rule_output_line[i], field) + if (!rule_used[field[2]]) + rule_output_line[i] = "" } } function abbreviate_rule_names( \ - abbr, f, field, i, n, r) + abbr, f, field, i, n, newdef, newline, r, \ + zoneline, zonelines, zonename) { - for (i = 0; i < nout; i++) { - n = split(output_line[i], field) + for (i = 0; i < nrule_out; i++) { + n = split(rule_output_line[i], field) if (n) { - f = field[1] == "Z" ? 4 : field[1] == "L" ? 0 : 2 - r = field[f] + r = field[2] if (r ~ /^[^-+0-9]/) { abbr = rule[r] if (!abbr) { rule[r] = abbr = gen_rule_name(r) } - field[f] = abbr - output_line[i] = make_line(n, field) + field[2] = abbr + rule_output_line[i] = make_line(n, field) } } } + for (zonename in zonedef) { + zonelines = split(zonedef[zonename], zoneline, /\n/) + newdef = "" + for (i = 1; i <= zonelines; i++) { + newline = zoneline[i] + n = split(newline, field) + f = i == 1 ? 4 : 2 + r = rule[field[f]] + if (r) { + field[f] = r + newline = make_line(n, field) + } + newdef = (newdef ? newdef "\n" : "") newline + } + zonedef[zonename] = newdef + } } function output_saved_lines( \ - i) + i, zonename) { - for (i = 0; i < nout; i++) - if (output_line[i]) - print output_line[i] + for (i = 0; i < nrule_out; i++) + if (rule_output_line[i]) + print rule_output_line[i] + + # When using gawk, output zones sorted by name. + # This makes the output a bit more compressible. + PROCINFO["sorted_in"] = "@ind_str_asc" + for (zonename in zonedef) + print zonedef[zonename] + + if (nlink_out) + for (i = 0; i < nlink_out; i++) + print link_output_line[i] + else { + # When using gawk, output links sorted by destination. + # This also helps compressibility a bit. + PROCINFO["sorted_in"] = "@val_type_asc" + for (zonename in linkdef) + printf "L %s %s\n", linkdef[zonename], zonename + } } BEGIN { diff --git a/zonenow.tab b/zonenow.tab index 2dbe8f00d1b8..b6f2910956fb 100644 --- a/zonenow.tab +++ b/zonenow.tab @@ -199,7 +199,7 @@ XX +2518+05518 Asia/Dubai Russia; Caucasus; Persian Gulf; Seychelles; Réunion XX +3431+06912 Asia/Kabul Afghanistan # # +05 -XX +4120+06918 Asia/Tashkent Russia; Tajikistan; Turkmenistan; Uzbekistan; Maldives +XX +4120+06918 Asia/Tashkent Russia; west Kazakhstan; Tajikistan; Turkmenistan; Uzbekistan; Maldives # # +05 - PKT XX +2452+06703 Asia/Karachi Pakistan ("PKT") @@ -215,6 +215,8 @@ XX +2743+08519 Asia/Kathmandu Nepal # # +06 XX +2343+09025 Asia/Dhaka Russia; Kyrgyzstan; Bhutan; Bangladesh; Chagos +# +06 until 2024-03-01; then +05 +XX +4315+07657 Asia/Almaty Kazakhstan (except western areas) # # +06:30 XX +1647+09610 Asia/Yangon Myanmar; Cocos |