1 News for the tz database
3 Release 2020e - 2020-12-22 15:14:34 -0800
6 Volgograd switches to Moscow time on 2020-12-27 at 02:00.
8 Changes to future timestamps
10 Volgograd changes time zone from +04 to +03 on 2020-12-27 at 02:00.
11 (Thanks to Alexander Krivenyshev and Stepan Golosunov.)
13 Changes to past timestamps
15 Correct many pre-1986 transitions, fixing entries originally
16 derived from Shanks. The fixes include:
17 - Australia: several 1917 through 1971 transitions
18 - Bahamas: several 1941 through 1945 transitions
19 - Bermuda: several 1917 through 1956 transitions
20 - Belize: several 1942 through 1968 transitions
21 - Ghana: several 1915 through 1956 transitions
22 - Israel and Palestine: several 1940 through 1985 transitions
23 - Kenya and adjacent: several 1908 through 1960 transitions
24 - Nigeria and adjacent: correcting LMT in Lagos, and several 1905
25 through 1919 transitions
26 - Seychelles: the introduction of standard time in 1907, not 1906
27 - Vanuatu: DST in 1973-1974, and a corrected 1984 transition
30 Because of the Australia change, Australia/Currie (King Island) is
31 no longer needed, as it is identical to Australia/Hobart for all
32 timestamps since 1970 and was therefore created by mistake.
33 Australia/Currie has been moved to the 'backward' file and its
34 corrected data moved to the 'backzone' file.
36 Changes to past time zone abbreviations and DST flags
38 To better match legislation in Turks and Caicos, the 2015 shift to
39 year-round observance of -04 is now modeled as AST throughout before
40 returning to Eastern Time with US DST in 2018, rather than as
41 maintaining EDT until 2015-11-01. (Thanks to P Chan.)
43 Changes to documentation
45 The zic man page now documents zic's coalescing of transitions
46 when a zone falls back just before DST springs forward.
49 Release 2020d - 2020-10-21 11:24:13 -0700
52 Palestine ends DST earlier than predicted, on 2020-10-24.
54 Changes to past and future timestamps
56 Palestine ends DST on 2020-10-24 at 01:00, instead of 2020-10-31
57 as previously predicted (thanks to Sharef Mustafa.) Its
58 2019-10-26 fall-back was at 00:00, not 01:00 (thanks to Steffen
59 Thorsen.) Its 2015-10-23 transition was at 01:00 not 00:00, and
60 its spring 2020 transition was on March 28 at 00:00, not March 27
61 (thanks to Pierre Cashon.) This affects Asia/Gaza and
62 Asia/Hebron. Assume future spring and fall transitions will be on
63 the Saturday preceding the last Sunday of March and October,
67 Release 2020c - 2020-10-16 11:15:53 -0700
70 Fiji starts DST later than usual, on 2020-12-20.
72 Changes to future timestamps
74 Fiji will start DST on 2020-12-20, instead of 2020-11-08 as
75 previously predicted. DST will still end on 2021-01-17.
76 (Thanks to Raymond Kumar and Alan Mintz.) Assume for now that
77 the later-than-usual start date is a one-time departure from the
80 Changes to build procedure
82 Rearguard tarballs now contain an empty file pacificnew.
83 Some older downstream software expects this file to exist.
84 (Problem reported by Mike Cullinan.)
87 Release 2020b - 2020-10-06 18:35:04 -0700
90 Revised predictions for Morocco's changes starting in 2023.
91 Canada's Yukon changes to -07 on 2020-11-01, not 2020-03-08.
92 Macquarie Island has stayed in sync with Tasmania since 2011.
93 Casey, Antarctica is at +08 in winter and +11 in summer.
94 zic no longer supports -y, nor the TYPE field of Rules.
96 Changes to future timestamps
98 Morocco's spring-forward after Ramadan is now predicted to occur
99 no sooner than two days after Ramadan, instead of one day.
100 (Thanks to Milamber.) The first altered prediction is for 2023,
101 now predicted to spring-forward on April 30 instead of April 23.
103 Changes to past and future timestamps
105 Casey Station, Antarctica has been using +08 in winter and +11 in
106 summer since 2018. The most recent transition from +08 to +11 was
107 2020-10-04 00:01. Also, Macquarie Island has been staying in
108 sync with Tasmania since 2011. (Thanks to Steffen Thorsen.)
110 Changes to past and future time zone abbreviations and DST flags
112 Canada's Yukon, represented by America/Whitehorse and
113 America/Dawson, changes its time zone rules from -08/-07 to
114 permanent -07 on 2020-11-01, not on 2020-03-08 as 2020a had it.
115 This change affects only the time zone abbreviation (MST vs PDT)
116 and daylight saving flag for the period between the two dates.
117 (Thanks to Andrew G. Smith.)
119 Changes to past timestamps
121 Correct several transitions for Hungary for 1918/1983.
122 For example, the 1983-09-25 fall-back was at 01:00, not 03:00.
123 (Thanks to Géza Nyáry.) Also, the 1890 transition to standard
124 time was on 11-01, not 10-01 (thanks to Michael Deckers).
126 The 1891 French transition was on March 16, not March 15. The
127 1911-03-11 French transition was at midnight, not a minute later.
128 Monaco's transitions were on 1892-06-01 and 1911-03-29, not
129 1891-03-15 and 1911-03-11. (Thanks to Michael Deckers.)
133 Support for zic's long-obsolete '-y YEARISTYPE' option has been
134 removed and, with it, so has support for the TYPE field in Rule
135 lines, which is now reserved for compatibility with earlier zic.
136 These features were previously deprecated in release 2015f.
137 (Thanks to Tim Parenti.)
139 zic now defaults to '-b slim' instead of to '-b fat'.
141 zic's new '-l -' and '-p -' options uninstall any existing
142 localtime and posixrules files, respectively.
144 The undocumented and ineffective tzsetwall function has been
147 Changes to build procedure
149 The Makefile now defaults POSIXRULES to '-', so the posixrules
150 feature (obsolete as of 2019b) is no longer installed by default.
152 Changes to documentation and commentary
154 The long-obsolete files pacificnew, systemv, and yearistype.sh have
155 been removed from the distribution. (Thanks to Tim Parenti.)
158 Release 2020a - 2020-04-23 16:03:47 -0700
161 Morocco springs forward on 2020-05-31, not 2020-05-24.
162 Canada's Yukon advanced to -07 year-round on 2020-03-08.
163 America/Nuuk renamed from America/Godthab.
164 zic now supports expiration dates for leap second lists.
166 Changes to future timestamps
168 Morocco's second spring-forward transition in 2020 will be May 31,
169 not May 24 as predicted earlier. (Thanks to Semlali Naoufal.)
170 Adjust future-year predictions to use the first Sunday after the
171 day after Ramadan, not the first Sunday after Ramadan.
173 Canada's Yukon, represented by America/Whitehorse and
174 America/Dawson, advanced to -07 year-round, beginning with its
175 spring-forward transition on 2020-03-08, and will not fall back on
176 2020-11-01. Although a government press release calls this
177 "permanent Pacific Daylight Saving Time", we prefer MST for
178 consistency with nearby Dawson Creek, Creston, and Fort Nelson.
179 (Thanks to Tim Parenti.)
181 Changes to past timestamps
183 Shanghai observed DST in 1919. (Thanks to Phake Nick.)
185 Changes to timezone identifiers
187 To reflect current usage in English better, America/Godthab has
188 been renamed to America/Nuuk. A backwards-compatibility link
189 remains for the old name.
193 localtime.c no longer mishandles timestamps after the last
194 transition in a TZif file with leap seconds and with daylight
195 saving time transitions projected into the indefinite future.
196 For example, with TZ='America/Los_Angeles' with leap seconds,
197 zdump formerly reported a DST transition on 2038-03-14
198 from 01:59:32.999... to 02:59:33 instead of the correct transition
199 from 01:59:59.999... to 03:00:00.
201 zic -L now supports an Expires line in the leapseconds file, and
202 truncates the TZif output accordingly. This propagates leap
203 second expiration information into the TZif file, and avoids the
204 abovementioned localtime.c bug as well as similar bugs present in
205 many client implementations. If no Expires line is present, zic
206 -L instead truncates the TZif output based on the #expires comment
207 present in leapseconds files distributed by tzdb 2018f and later;
208 however, this usage is obsolescent. For now, the distributed
209 leapseconds file has an Expires line that is commented out, so
210 that the file can be fed to older versions of zic which ignore the
211 commented-out line. Future tzdb distributions are planned to
212 contain a leapseconds file with an Expires line.
214 The configuration macros HAVE_TZNAME and USG_COMPAT should now be
215 set to 1 if the system library supports the feature, and 2 if not.
216 As before, these macros are nonzero if tzcode should support the
217 feature, zero otherwise.
219 The configuration macro ALTZONE now has the same values with the
220 same meaning as HAVE_TZNAME and USG_COMPAT.
222 The code's defense against CRLF in leap-seconds.list is now
223 portable to POSIX awk. (Problem reported by Deborah Goldsmith.)
225 Although the undocumented tzsetwall function is not changed in
226 this release, it is now deprecated in preparation for removal in
227 future releases. Due to POSIX requirements, tzsetwall has not
228 worked for some time. Any code that uses it should instead use
229 tzalloc(NULL) or, if portability trumps thread-safety, should
230 unset the TZ environment variable.
232 Changes to commentary
234 The Îles-de-la-Madeleine and the Listuguj reserve are noted as
235 following America/Halifax, and comments about Yukon's "south" and
236 "north" have been corrected to say "east" and "west". (Thanks to
240 Release 2019c - 2019-09-11 08:59:48 -0700
243 Fiji observes DST from 2019-11-10 to 2020-01-12.
244 Norfolk Island starts observing Australian-style DST.
246 Changes to future timestamps
248 Fiji's next DST transitions will be 2019-11-10 and 2020-01-12
249 instead of 2019-11-03 and 2020-01-19. (Thanks to Raymond Kumar.)
250 Adjust future guesses accordingly.
252 Norfolk Island will observe Australian-style DST starting in
253 spring 2019. The first transition is on 2019-10-06. (Thanks to
254 Kyle Czech and Michael Deckers.)
256 Changes to past timestamps
258 Many corrections to time in Turkey from 1940 through 1985.
259 (Thanks to Oya Vulaş via Alois Treindl, and to Kıvanç Yazan.)
261 The Norfolk Island 1975-03-02 transition was at 02:00 standard
262 time, not 02:00 DST. (Thanks to Michael Deckers.)
264 South Korea observed DST from 1948 through 1951. Although this
265 info was supposed to appear in release 2014j, a typo inadvertently
266 suppressed the change. (Thanks to Alois Treindl.)
268 Detroit observed DST in 1967 and 1968 following the US DST rules,
269 except that its 1967 DST began on June 14 at 00:01. (Thanks to
270 Alois Treindl for pointing out that the old data entries were
273 Fix several errors in pre-1970 transitions in Perry County, IN.
274 (Thanks to Alois Triendl for pointing out the 1967/9 errors.)
276 Edmonton did not observe DST in 1967 or 1969. In 1946 Vancouver
277 ended DST on 09-29 not 10-13, and Vienna ended DST on 10-07 not
278 10-06. In 1945 Königsberg (now Kaliningrad) switched from +01/+02
279 to +02/+03 on 04-10 not 01-01, and its +02/+03 is abbreviated
280 EET/EEST, not CET/CEST. (Thanks to Alois Triendl.) In 1946
281 Königsberg switched to +03 on 04-07 not 01-01.
283 In 1946 Louisville switched from CST to CDT on 04-28 at 00:01, not
284 01-01 at 00:00. (Thanks to Alois Treindl and Michael Deckers.)
285 Also, it switched from CST to CDT on 1950-04-30, not 1947-04-27.
287 The 1892-05-01 transition in Brussels was at 00:17:30, not at noon.
288 (Thanks to Michael Deckers.)
290 Changes to past time zone abbreviations and DST flags
292 Hong Kong Winter Time, observed from 1941-10-01 to 1941-12-25,
293 is now flagged as DST and is abbreviated HKWT not HKT.
297 leapseconds.awk now relies only on its input data, rather than
298 also relying on its comments. (Inspired by code from Dennis
299 Ferguson and Chris Woodbury.)
301 The code now defends against CRLFs in leap-seconds.list.
302 (Thanks to Brian Inglis and Chris Woodbury.)
304 Changes to documentation and commentary
306 theory.html discusses leap seconds. (Thanks to Steve Summit.)
308 Nashville's newspapers dueled about the time of day in the 1950s.
309 (Thanks to John Seigenthaler.)
311 Liechtenstein observed Swiss DST in 1941/2.
312 (Thanks to Alois Treindl.)
315 Release 2019b - 2019-07-01 00:09:53 -0700
318 Brazil no longer observes DST.
319 'zic -b slim' outputs smaller TZif files; please try it out.
320 Palestine's 2019 spring-forward transition was on 03-29, not 03-30.
322 Changes to future timestamps
324 Brazil has canceled DST and will stay on standard time indefinitely.
325 (Thanks to Steffen Thorsen, Marcus Diniz, and Daniel Soares de
328 Predictions for Morocco now go through 2087 instead of 2037, to
329 work around a problem on newlib when using TZif files output by
330 zic 2019a or earlier. (Problem reported by David Gauchard.)
332 Changes to past and future timestamps
334 Palestine's 2019 spring transition was 03-29 at 00:00, not 03-30
335 at 01:00. (Thanks to Sharef Mustafa and Even Scharning.) Guess
336 future transitions to be March's last Friday at 00:00.
338 Changes to past timestamps
340 Hong Kong's 1941-06-15 spring-forward transition was at 03:00, not
341 03:30. Its 1945 transition from JST to HKT was on 11-18 at 02:00,
342 not 09-15 at 00:00. In 1946 its spring-forward transition was on
343 04-21 at 00:00, not the previous day at 03:30. From 1946 through
344 1952 its fall-back transitions occurred at 04:30, not at 03:30.
345 In 1947 its fall-back transition was on 11-30, not 12-30.
348 Changes to past time zone abbreviations
350 Italy's 1866 transition to Rome Mean Time was on December 12, not
351 September 22. This affects only the time zone abbreviation for
352 Europe/Rome between those dates. (Thanks to Stephen Trainor and
355 Changes affecting metadata only
357 Add info about the Crimea situation in zone1970.tab and zone.tab.
358 (Problem reported by Serhii Demediuk.)
362 zic's new -b option supports a way to control data bloat and to
363 test for year-2038 bugs in software that reads TZif files.
364 'zic -b fat' and 'zic -b slim' generate larger and smaller output;
365 for example, changing from fat to slim shrinks the Europe/London
366 file from 3648 to 1599 bytes, saving about 56%. Fat and slim
367 files represent the same set of timestamps and use the same TZif
368 format as documented in tzfile(5) and in Internet RFC 8536.
369 Fat format attempts to work around bugs or incompatibilities in
370 older software, notably software that mishandles 64-bit TZif data
371 or uses obsolete TZ strings like "EET-2EEST" that lack DST rules.
372 Slim format is more efficient and does not work around 64-bit bugs
373 or obsolete TZ strings. Currently zic defaults to fat format
374 unless you compile with -DZIC_BLOAT_DEFAULT=\"slim\"; this
375 out-of-the-box default is intended to change in future releases
376 as the buggy software often mishandles timestamps anyway.
378 zic no longer treats a set of rules ending in 2037 specially.
379 Previously, zic assumed that such a ruleset meant that future
380 timestamps could not be predicted, and therefore omitted a
381 POSIX-like TZ string in the TZif output. The old behavior is no
382 longer needed for current tzdata, and caused problems with newlib
383 when used with older tzdata (reported by David Gauchard).
385 zic no longer generates some artifact transitions. For example,
386 Europe/London no longer has a no-op transition in January 1996.
388 Changes to build procedure
390 tzdata.zi now assumes zic 2017c or later. This shrinks tzdata.zi
393 Changes to documentation and commentary
395 The Makefile now documents the POSIXRULES macro as being obsolete,
396 and similarly, zic's -p POSIXRULES option is now documented as
397 being obsolete. Although the POSIXRULES feature still exists and
398 works as before, in practice it is rarely used for its intended
399 purpose, and it does not work either in the default reference
400 implementation (for timestamps after 2037) or in common
401 implementations such as GNU/Linux (for contemporary timestamps).
402 Since POSIXRULES was designed primarily as a temporary transition
403 facility for System V platforms that died off decades ago, it is
404 being decommissioned rather than institutionalized.
406 New info on Bonin Islands and Marcus (thanks to Wakaba and Phake Nick).
409 Release 2019a - 2019-03-25 22:01:33 -0700
412 Palestine "springs forward" on 2019-03-30 instead of 2019-03-23.
413 Metlakatla "fell back" to rejoin Alaska Time on 2019-01-20 at 02:00.
415 Changes to past and future timestamps
417 Palestine will not start DST until 2019-03-30, instead of 2019-03-23 as
418 previously predicted. Adjust our prediction by guessing that spring
419 transitions will be between 24 and 30 March, which matches recent practice
420 since 2016. (Thanks to Even Scharning and Tim Parenti.)
422 Metlakatla ended its observance of Pacific standard time,
423 rejoining Alaska Time, on 2019-01-20 at 02:00. (Thanks to Ryan
424 Stanley and Tim Parenti.)
426 Changes to past timestamps
428 Israel observed DST in 1980 (08-02/09-13) and 1984 (05-05/08-25).
429 (Thanks to Alois Treindl and Isaac Starkman.)
431 Changes to time zone abbreviations
433 Etc/UCT is now a backward-compatibility link to Etc/UTC, instead
434 of being a separate zone that generates the abbreviation "UCT",
435 which nowadays is typically a typo. (Problem reported by Isiah
440 zic now has an -r option to limit the time range of output data.
441 For example, 'zic -r @1000000000' limits the output data to
442 timestamps starting 1000000000 seconds after the Epoch.
443 This helps shrink output size and can be useful for applications
444 not needing the full timestamp history, such as TZDIST truncation;
445 see Internet RFC 8536 section 5.1. (Inspired by a feature request
446 from Christopher Wong, helped along by bug reports from Wong and
449 Changes to documentation
451 Mention Internet RFC 8536 (February 2019), which documents TZif.
453 tz-link.html now cites tzdata-meta
454 <https://tzdata-meta.timtimeonline.com/>.
457 Release 2018i - 2018-12-30 11:05:43 -0800
460 São Tomé and Príncipe switches from +01 to +00 on 2019-01-01.
462 Changes to future timestamps
464 Due to a change in government, São Tomé and Príncipe switches back
465 from +01 to +00 on 2019-01-01 at 02:00. (Thanks to Vadim
466 Nasardinov and Michael Deckers.)
469 Release 2018h - 2018-12-23 17:59:32 -0800
472 Qyzylorda, Kazakhstan moved from +06 to +05 on 2018-12-21.
473 New zone Asia/Qostanay because Qostanay, Kazakhstan didn't move.
474 Metlakatla, Alaska observes PST this winter only.
475 Guess Morocco will continue to adjust clocks around Ramadan.
476 Add predictions for Iran from 2038 through 2090.
478 Changes to future timestamps
480 Guess that Morocco will continue to fall back just before and
481 spring forward just after Ramadan, the practice since 2012.
482 (Thanks to Maamar Abdelkader.) This means Morocco will observe
483 negative DST during Ramadan in main and vanguard formats, and in
484 rearguard format it stays in the +00 timezone and observes
485 ordinary DST in all months other than Ramadan. As before, extend
486 this guesswork to the year 2037. As a consequence, Morocco is
487 scheduled to observe three DST transitions in some Gregorian years
488 (e.g., 2033) due to the mismatch between the Gregorian and Islamic
491 The table of exact transitions for Iranian DST has been extended.
492 It formerly cut off before the year 2038 in a nod to 32-bit time_t.
493 It now cuts off before 2091 as there is doubt about how the Persian
494 calendar will treat 2091. This change predicts DST transitions in
495 2038-9, 2042-3, and 2046-7 to occur one day later than previously
496 predicted. As before, post-cutoff transitions are approximated.
498 Changes to past and future timestamps
500 Qyzylorda (aka Kyzylorda) oblast in Kazakhstan moved from +06 to
501 +05 on 2018-12-21. This is a zone split as Qostanay (aka
502 Kostanay) did not switch, so create a zone Asia/Qostanay.
504 Metlakatla moved from Alaska to Pacific standard time on 2018-11-04.
505 It did not change clocks that day and remains on -08 this winter.
506 (Thanks to Ryan Stanley.) It will revert to the usual Alaska
507 rules next spring, so this change affects only timestamps
508 from 2018-11-04 through 2019-03-10.
510 Change to past timestamps
512 Kwajalein's 1993-08-20 transition from -12 to +12 was at 24:00,
513 not 00:00. I transcribed the time incorrectly from Shanks.
514 (Thanks to Phake Nick.)
516 Nauru's 1979 transition was on 02-10 at 02:00, not 05-01 at 00:00.
517 (Thanks to Phake Nick.)
519 Guam observed DST irregularly from 1959 through 1977.
520 (Thanks to Phake Nick.)
522 Hong Kong observed DST in 1941 starting 06-15 (not 04-01), then on
523 10-01 changed standard time to +08:30 (not +08). Its transition
524 back to +08 after WWII was on 1945-09-15, not the previous day.
525 Its 1904-10-30 change took effect at 01:00 +08 (not 00:00 LMT).
526 (Thanks to Phake Nick, Steve Allen, and Joseph Myers.) Also,
527 its 1952 fallback was on 11-02 (not 10-25).
529 This release contains many changes to timestamps before 1946 due
530 to Japanese possession or occupation of Pacific/Chuuk,
531 Pacific/Guam, Pacific/Kosrae, Pacific/Kwajalein, Pacific/Majuro,
532 Pacific/Nauru, Pacific/Palau, and Pacific/Pohnpei.
533 (Thanks to Phake Nick.)
535 Assume that the Spanish East Indies was like the Philippines and
536 observed American time until the end of 1844. This affects
537 Pacific/Chuuk, Pacific/Kosrae, Pacific/Palau, and Pacific/Pohnpei.
539 Changes to past tm_isdst flags
541 For the recent Morocco change, the tm_isdst flag should be 1 from
542 2018-10-27 00:00 to 2018-10-28 03:00. (Thanks to Michael Deckers.)
543 Give a URL to the official decree. (Thanks to Matt Johnson.)
546 Release 2018g - 2018-10-26 22:22:45 -0700
549 Morocco switches to permanent +01 on 2018-10-28.
551 Changes to future timestamps
553 Morocco switches from +00/+01 to permanent +01 effective 2018-10-28,
554 so its clocks will not fall back as previously scheduled.
555 (Thanks to Mohamed Essedik Najd and Brian Inglis.)
559 When generating TZif files with leap seconds, zic no longer uses a
560 format that trips up older 32-bit clients, fixing a bug introduced
561 in 2018f. (Reported by Daniel Fischer.) Also, the zic workaround
562 for QTBUG-53071 now also works for TZif files with leap seconds.
564 The translator to rearguard format now rewrites the line
565 "Rule Japan 1948 1951 - Sep Sat>=8 25:00 0 S" to
566 "Rule Japan 1948 1951 - Sep Sun>=9 1:00 0 S".
567 This caters to zic before 2007 and to Oracle TZUpdater 2.2.0
568 and earlier. (Reported by Christos Zoulas.)
570 Changes to past time zone abbreviations
572 Change HDT to HWT/HPT for WWII-era abbreviations in Hawaii.
573 This reverts to 2011h, as the abbreviation change in 2011i was
576 Changes to documentation
578 tzfile.5 has new sections on interoperability issues.
581 Release 2018f - 2018-10-18 00:14:18 -0700
584 Volgograd moves from +03 to +04 on 2018-10-28.
585 Fiji ends DST 2019-01-13, not 2019-01-20.
586 Most of Chile changes DST dates, effective 2019-04-06.
588 Changes to future timestamps
590 Volgograd moves from +03 to +04 on 2018-10-28 at 02:00.
591 (Thanks to Alexander Fetisov and Stepan Golosunov.)
593 Fiji ends DST 2019-01-13 instead of the 2019-01-20 previously
594 predicted. (Thanks to Raymond Kumar.) Adjust future predictions
597 Most of Chile will end DST on the first Saturday in April at 24:00 mainland
598 time, and resume DST on the first Saturday in September at 24:00 mainland
599 time. The changes are effective from 2019-04-06, and do not affect the
600 Magallanes region modeled by America/Punta_Arenas. (Thanks to Juan Correa
601 and Tim Parenti.) Adjust future predictions accordingly.
603 Changes to past timestamps
605 The 2018-05-05 North Korea 30-minute time zone change took place
606 at 23:30 the previous day, not at 00:00 that day.
608 China's 1988 spring-forward transition was on April 17, not
609 April 10. Its DST transitions in 1986/91 were at 02:00, not 00:00.
612 Fix several issues for Macau before 1992. Macau's pre-1904 LMT
613 was off by 10 s. Macau switched to +08 in 1904 not 1912, and
614 temporarily switched to +09/+10 during World War II. Macau
615 observed DST in 1942/79, not 1961/80, and there were several
616 errors for transition times and dates. (Thanks to P Chan.)
618 The 1948-1951 fallback transitions in Japan were at 25:00 on
619 September's second Saturday, not at 24:00. (Thanks to Phake Nick.)
620 zic turns this into 01:00 on the day after September's second
621 Saturday, which is the best that POSIX or C platforms can do.
623 Incorporate 1940-1949 Asia/Shanghai DST transitions from a 2014
624 paper by Li Yu, replacing more-questionable data from Shanks.
626 Changes to time zone abbreviations
628 Use "PST" and "PDT" for Philippine time. (Thanks to Paul Goyette.)
632 zic now always generates TZif files where time type 0 is used for
633 timestamps before the first transition. This simplifies the
634 reading of TZif files and should not affect behavior of existing
635 TZif readers because the same set of time types is used; only
636 their internal indexes may have changed. This affects only the
637 legacy zones EST5EDT, CST6CDT, MST7MDT, PST8PDT, CET, MET, and
638 EET, which previously used nonzero types for these timestamps.
640 Because of the type 0 change, zic no longer outputs a dummy
641 transition at time -2**59 (before the Big Bang), as clients should
642 no longer need this to handle historical timestamps correctly.
643 This reverts a change introduced in 2013d and shrinks most TZif
644 files by a few bytes.
646 zic now supports negative time-of-day in Rule and Leap lines, e.g.,
647 "Rule X min max - Apr lastSun -6:00 1:00 -" means the transition
648 occurs at 18:00 on the Saturday before the last Sunday in April.
649 This behavior was documented in 2018a but the code did not
650 entirely match the documentation.
652 localtime.c no longer requires at least one time type in TZif
653 files that lack transitions or have a POSIX-style TZ string. This
654 future-proofs the code against possible future extensions to the
655 format that would allow TZif files with POSIX-style TZ strings and
656 without transitions or time types.
658 A read-access subscript error in localtime.c has been fixed.
659 It could occur only in TZif files with timecnt == 0, something that
660 does not happen in practice now but could happen in future versions.
662 localtime.c no longer ignores TZif POSIX-style TZ strings that
663 specify only standard time. Instead, these TZ strings now
664 override the default time type for timestamps after the last
665 transition (or for all timestamps if there are no transitions),
666 just as DST strings specifying DST have always done.
668 leapseconds.awk now outputs "#updated" and "#expires" comments,
669 and supports leap seconds at the ends of months other than June
670 and December. (Inspired by suggestions from Chris Woodbury.)
672 Changes to documentation
674 New restrictions: A Rule name must start with a character that
675 is neither an ASCII digit nor "-" nor "+", and an unquoted name
676 should not use characters in the set "!$%&'()*,/:;<=>?@[\]^`{|}~".
677 The latter restriction makes room for future extensions (a
678 possibility noted by Tom Lane).
680 tzfile.5 now documents what time types apply before the first and
681 after the last transition, if any.
683 Documentation now uses the spelling "timezone" for a TZ setting
684 that determines timestamp history, and "time zone" for a
685 geographic region currently sharing the same standard time.
687 The name "TZif" is now used for the tz binary data format.
689 tz-link.htm now mentions the A0 TimeZone Migration utilities.
690 (Thanks to Aldrin Martoq for the link.)
692 Changes to build procedure
694 New 'make' target 'rearguard_tarballs' to build the rearguard
695 tarball only. This is a convenience on platforms that lack lzip
696 if you want to build the rearguard tarball. (Problem reported by
699 tzdata.zi is now more stable from release to release. (Problem
700 noted by Tom Lane.) It is also a bit shorter.
702 tzdata.zi now can contain comment lines documenting configuration
703 information, such as which data format was selected, which input
704 files were used, and how leap seconds are treated. (Problems
705 noted by Lester Caine and Brian Inglis.) If the Makefile defaults
706 are used these comment lines are absent, for backward
707 compatibility. A redistributor intending to alter its copy of the
708 files should also append "-LABEL" to the 'version' file's first
709 line, where "LABEL" identifies the redistributor's change.
712 Release 2018e - 2018-05-01 23:42:51 -0700
716 North Korea switches back to +09 on 2018-05-05.
717 The main format uses negative DST again, for Ireland etc.
718 'make tarballs' now also builds a rearguard tarball.
719 New 's' and 'd' suffixes in SAVE columns of Rule and Zone lines.
721 Changes to past and future timestamps
723 North Korea switches back from +0830 to +09 on 2018-05-05.
724 (Thanks to Kang Seonghoon, Arthur David Olson, Seo Sanghyeon,
727 Bring back the negative-DST changes of 2018a, except be more
728 compatible with data parsers that do not support negative DST.
729 Also, this now affects historical timestamps in Namibia and the
730 former Czechoslovakia, not just Ireland. The main format now uses
731 negative DST to model timestamps in Europe/Dublin (from 1971 on),
732 Europe/Prague (1946/7), and Africa/Windhoek (1994/2017). This
733 does not affect UT offsets, only time zone abbreviations and the
734 tm_isdst flag. Also, this does not affect rearguard or vanguard
735 formats; effectively the main format now uses vanguard instead of
736 rearguard format. Data parsers that do not support negative DST
737 can still use data from the rearguard tarball described below.
739 Changes to build procedure
741 The command 'make tarballs' now also builds the tarball
742 tzdataVERSION-rearguard.tar.gz, which is like tzdataVERSION.tar.gz
743 except that it uses rearguard format intended for trailing-edge
746 Changes to data format and to code
748 The SAVE column of Rule and Zone lines can now have an 's' or 'd'
749 suffix, which specifies whether the adjusted time is standard time
750 or daylight saving time. If no suffix is given, daylight saving
751 time is used if and only if the SAVE column is nonzero; this is
752 the longstanding behavior. Although this new feature is not used
753 in tzdata, it could be used to specify the legal time in Namibia
754 1994-2017, as opposed to the popular time (see below).
756 Changes to past timestamps
758 From 1994 through 2017 Namibia observed DST in winter, not summer.
759 That is, it used negative DST, as Ireland still does. This change
760 does not affect UTC offsets; it affects only the tm_isdst flag and
761 the abbreviation used during summer, which is now CAT, not WAST.
762 Although (as noted by Michael Deckers) summer and winter time were
763 both simply called "standard time" in Namibian law, in common
764 practice winter time was considered to be DST (as noted by Stephen
765 Colebourne). The full effect of this change is only in vanguard
766 and main format; in rearguard format, the tm_isdst flag is still
767 zero in winter and nonzero in summer.
769 In 1946/7 Czechoslovakia also observed negative DST in winter.
770 The full effect of this change is only in vanguard and main
771 formats; in rearguard format, it is modeled as plain GMT without
772 daylight saving. Also, the dates of some 1944/5 DST transitions
773 in Czechoslovakia have been changed.
776 Release 2018d - 2018-03-22 07:05:46 -0700
780 Palestine starts DST a week earlier in 2018.
781 Add support for vanguard and rearguard data consumers.
782 Add subsecond precision to source data format, though not to data.
784 Changes to future timestamps
786 In 2018, Palestine starts DST on March 24, not March 31.
787 Adjust future predictions accordingly. (Thanks to Sharef Mustafa.)
789 Changes to past and future timestamps
791 Casey Station in Antarctica changed from +11 to +08 on 2018-03-11
792 at 04:00. (Thanks to Steffen Thorsen.)
794 Changes to past timestamps
796 Historical transitions for Uruguay, represented by
797 America/Montevideo, have been updated per official legal documents,
798 replacing previous data mainly originating from the inventions of
799 Shanks & Pottenger. This has resulted in adjustments ranging from
800 30 to 90 minutes in either direction over at least two dozen
801 distinct periods ranging from one day to several years in length.
802 A mere handful of pre-1991 transitions are unaffected; data since
803 then has come from more reliable contemporaneous reporting. These
804 changes affect various timestamps in 1920-1923, 1936, 1939,
805 1942-1943, 1959, 1966-1970, 1972, 1974-1980, and 1988-1990.
806 Additionally, Uruguay's pre-standard-time UT offset has been
807 adjusted westward by 7 seconds, from UT-03:44:44 to UT-03:44:51, to
808 match the location of the Observatory of the National Meteorological
809 Institute in Montevideo.
810 (Thanks to Jeremie Bonjour, Tim Parenti, and Michael Deckers.)
812 Enderbury and Kiritimati skipped New Year's Eve 1994, not
813 New Year's Day 1995. (Thanks to Kerry Shetline.)
815 Fix the 1912-01-01 transition for Portugal and its colonies.
816 This transition was at 00:00 according to the new UT offset, not
817 according to the old one. Also assume that Cape Verde switched on
818 the same date as the rest, not in 1907. This affects
819 Africa/Bissau, Africa/Sao_Tome, Asia/Macau, Atlantic/Azores,
820 Atlantic/Cape_Verde, Atlantic/Madeira, and Europe/Lisbon.
821 (Thanks to Michael Deckers.)
823 Fix an off-by-1 error for pre-1913 timestamps in Jamaica and in
826 Changes to past time zone abbreviations
828 MMT took effect in Uruguay from 1908-06-10, not 1898-06-28. There
829 is no clock change associated with the transition.
831 Changes to build procedure
833 The new DATAFORM macro in the Makefile lets the installer choose
834 among three source data formats. The idea is to lessen downstream
835 disruption when data formats are improved.
837 * DATAFORM=vanguard installs from the latest, bleeding-edge
838 format. DATAFORM=main (the default) installs from the format
839 used in the 'africa' etc. files. DATAFORM=rearguard installs
840 from a trailing-edge format. Eventually, elements of today's
841 vanguard format should move to the main format, and similarly
842 the main format's features should eventually move to the
845 * In the current version, the main and rearguard formats are
846 identical and match that of 2018c, so this change does not
847 affect default behavior. The vanguard format currently contains
848 one feature not in the main format: negative SAVE values. This
849 improves support for Ireland, which uses Irish Standard Time
850 (IST, UTC+01) in summer and GMT (UTC) in winter. tzcode has
851 supported negative SAVE values for decades, and this feature
852 should move to the main format soon. However, it will not move
853 to the rearguard format for quite some time because some
854 downstream parsers do not support it.
856 * The build procedure constructs three files vanguard.zi, main.zi,
857 and rearguard.zi, one for each format. Although the files
858 represent essentially the same data, they may have minor
859 discrepancies that users are not likely to notice. The files
860 are intended for downstream data consumers and are not
861 installed. Zoneinfo parsers that do not support negative SAVE values
862 should start using rearguard.zi, so that they will be unaffected
863 when the negative-DST feature moves from vanguard to main.
864 Bleeding-edge Zoneinfo parsers that support the new features
865 already can use vanguard.zi; in this respect, current tzcode is
868 The Makefile should now be safe for parallelized builds, and 'make
869 -j to2050new.tzs' is now much faster on a multiprocessor host
872 When built with -DSUPPRESS_TZDIR, the tzcode library no longer
873 prepends TZDIR/ to file names that do not begin with '/'. This is
874 not recommended for general use, due to its security implications.
875 (From a suggestion by Manuela Friedrich.)
879 zic now accepts subsecond precision in expressions like
880 00:19:32.13, which is approximately the legal time of the
881 Netherlands from 1835 to 1937. However, because it is
882 questionable whether the few recorded uses of non-integer offsets
883 had subsecond precision in practice, there are no plans for tzdata
884 to use this feature. (Thanks to Steve Allen for pointing out
885 the limitations of historical data in this area.)
887 The code is a bit more portable to MS-Windows. Installers can
888 compile with -DRESERVE_STD_EXT_IDS on MS-Windows platforms that
889 reserve identifiers like 'localtime'. (Thanks to Manuela
892 Changes to documentation and commentary
894 theory.html now outlines tzdb's extensions to POSIX's model for
895 civil time, and has a section "POSIX features no longer needed"
896 that lists POSIX API components that are now vestigial.
897 (From suggestions by Steve Summit.) It also better distinguishes
898 time zones from tz regions. (From a suggestion by Guy Harris.)
900 Commentary is now more consistent about using the phrase "daylight
901 saving time", to match the C name tm_isdst. Daylight saving time
902 need not occur in summer, and need not have a positive offset from
905 Commentary about historical transitions in Uruguay has been expanded
906 with links to many relevant legal documents.
907 (Thanks to Tim Parenti.)
909 Commentary now uses some non-ASCII characters with Unicode value
910 less than U+0100, as they can be useful and should work even with
911 older editors such as XEmacs.
914 Release 2018c - 2018-01-22 23:00:44 -0800
917 Revert Irish changes that relied on negative SAVE values.
921 Revert the 2018a change to Europe/Dublin. As before, this change
922 does not affect UT offsets or abbreviations; it affects only
923 whether timestamps are considered to be standard time or
924 daylight-saving time, as expressed in the tm_isdst flag of C's
925 struct tm type. This reversion is intended to be a temporary
926 workaround for problems discovered with downstream uses of
927 releases 2018a and 2018b, which implemented Irish time by using
928 negative SAVE values in the Eire rules of the 'europe' file.
929 Although negative SAVE values have been part of tzcode for many
930 years and are supported by many platforms, they were not
931 documented before 2018a and ICU and OpenJDK do not currently
932 support them. A mechanism to export data to platforms lacking
933 support for negative DST is planned to be developed before the
934 change is reapplied. (Problems reported by Deborah Goldsmith and
937 Changes to past timestamps
939 Japanese DST transitions (1948-1951) were Sundays at 00:00, not
940 Saturdays or Sundays at 02:00. (Thanks to Takayuki Nikai.)
942 Changes to build procedure
944 The build procedure now works around mawk 1.3.3's lack of support
945 for character class expressions. (Problem reported by Ohyama.)
948 Release 2018b - 2018-01-17 23:24:48 -0800
951 Fix a packaging problem in tz2018a, which was missing 'pacificnew'.
953 Changes to build procedure
955 The distribution now contains the file 'pacificnew' again.
956 This file was inadvertantly omitted in the 2018a distribution.
957 (Problem reported by Matias Fonzo.)
960 Release 2018a - 2018-01-12 22:29:21 -0800
963 São Tomé and Príncipe switched from +00 to +01.
964 Brazil's DST will now start on November's first Sunday.
965 Ireland's standard time is now in the summer, not the winter.
966 Use Debian-style installation locations, instead of 4.3BSD-style.
969 Changes to past and future timestamps
971 São Tomé and Príncipe switched from +00 to +01 on 2018-01-01 at
972 01:00. (Thanks to Steffen Thorsen and Michael Deckers.)
974 Changes to future timestamps
976 Starting in 2018 southern Brazil will begin DST on November's
977 first Sunday instead of October's third Sunday. (Thanks to
980 Changes to past timestamps
982 A discrepancy of 4 s in timestamps before 1931 in South Sudan has
983 been corrected. The 'backzone' and 'zone.tab' files did not agree
984 with the 'africa' and 'zone1970.tab' files. (Problem reported by
987 The abbreviation invented for Bolivia Summer Time (1931-2) is now
988 BST instead of BOST, to be more consistent with the convention
989 used for Latvian Summer Time (1918-9) and for British Summer Time.
993 Change Europe/Dublin so that it observes Irish Standard Time (UT
994 +01) in summer and GMT (as negative daylight-saving) in winter,
995 instead of observing standard time (GMT) in winter and Irish
996 Summer Time (UT +01) in summer. This change does not affect UT
997 offsets or abbreviations; it affects only whether timestamps are
998 considered to be standard time or daylight-saving time, as
999 expressed in the tm_isdst flag of C's struct tm type.
1000 (Discrepancy noted by Derick Rethans.)
1002 Changes to build procedure
1004 The default installation locations have been changed to mostly
1005 match Debian circa 2017, instead of being designed as an add-on to
1006 4.3BSD circa 1986. This affects the Makefile macros TOPDIR,
1007 TZDIR, MANDIR, and LIBDIR. New Makefile macros TZDEFAULT, USRDIR,
1008 USRSHAREDIR, BINDIR, ZDUMPDIR, and ZICDIR let installers tailor
1009 locations more precisely. (This responds to suggestions from
1010 Brian Inglis and from Steve Summit.)
1012 The default installation procedure no longer creates the
1013 backward-compatibility link US/Pacific-New, which causes
1014 confusion during user setup (e.g., see Debian bug 815200).
1015 Use 'make BACKWARD="backward pacificnew"' to create the link
1016 anyway, for now. Eventually we plan to remove the link entirely.
1018 tzdata.zi now contains a version-number comment.
1019 (Suggested by Tom Lane.)
1021 The Makefile now quotes values like BACKWARD more carefully when
1022 passing them to the shell. (Problem reported by Zefram.)
1024 Builders no longer need to specify -DHAVE_SNPRINTF on platforms
1025 that have snprintf and use pre-C99 compilers. (Problem reported
1030 zic has a new option -t FILE that specifies the location of the
1031 file that determines local time when TZ is unset. The default for
1032 this location can be configured via the new TZDEFAULT makefile
1033 macro, which defaults to /etc/localtime.
1035 Diagnostics and commentary now distinguish UT from UTC more
1036 carefully; see theory.html for more information about UT vs UTC.
1038 zic has been ported to GCC 8's -Wstringop-truncation option.
1039 (Problem reported by Martin Sebor.)
1041 Changes to documentation and commentary
1043 The zic man page now documents the longstanding behavior that
1044 times and years can be out of the usual range, with negative times
1045 counting backwards from midnight and with year 0 preceding year 1.
1046 (Problem reported by Michael Deckers.)
1048 The theory.html file now mentions the POSIX limit of six chars
1049 per abbreviation, and lists alphabetic abbreviations used.
1051 The files tz-art.htm and tz-link.htm have been renamed to
1052 tz-art.html and tz-link.html, respectively, for consistency with
1053 other file names and to simplify web server configuration.
1056 Release 2017c - 2017-10-20 14:49:34 -0700
1059 Northern Cyprus switches from +03 to +02/+03 on 2017-10-29.
1060 Fiji ends DST 2018-01-14, not 2018-01-21.
1061 Namibia switches from +01/+02 to +02 on 2018-04-01.
1062 Sudan switches from +03 to +02 on 2017-11-01.
1063 Tonga likely switches from +13/+14 to +13 on 2017-11-05.
1064 Turks & Caicos switches from -04 to -05/-04 on 2018-11-04.
1065 A new file tzdata.zi now holds a small text copy of all data.
1066 The zic input format has been regularized slightly.
1068 Changes to future timestamps
1070 Northern Cyprus has decided to resume EU rules starting
1071 2017-10-29, thus reinstituting winter time.
1073 Fiji ends DST 2018-01-14 instead of the 2018-01-21 previously
1074 predicted. (Thanks to Dominic Fok.) Adjust future predictions
1077 Namibia will switch from +01 with DST to +02 all year on
1078 2017-09-03 at 02:00. This affects UT offsets starting 2018-04-01
1079 at 02:00. (Thanks to Steffen Thorsen.)
1081 Sudan will switch from +03 to +02 on 2017-11-01. (Thanks to Ahmed
1082 Atyya and Yahia Abdalla.) South Sudan is not switching, so
1083 Africa/Juba is no longer a link to Africa/Khartoum.
1085 Tonga has likely ended its experiment with DST, and will not
1086 adjust its clocks on 2017-11-05. Although Tonga has not announced
1087 whether it will continue to observe DST, the IATA is assuming that
1088 it will not. (Thanks to David Wade.)
1090 Turks & Caicos will switch from -04 all year to -05 with US DST on
1091 2018-03-11 at 03:00. This affects UT offsets starting 2018-11-04
1092 at 02:00. (Thanks to Steffen Thorsen.)
1094 Changes to past timestamps
1096 Namibia switched from +02 to +01 on 1994-03-21, not 1994-04-03.
1097 (Thanks to Arthur David Olson.)
1099 Detroit did not observe DST in 1967.
1101 Use railway time for Asia/Kolkata before 1941, by switching to
1102 Madras local time (UT +052110) in 1870, then to IST (UT +0530) in
1103 1906. Also, treat 1941-2's +0630 as DST, like 1942-5.
1105 Europe/Dublin's 1946 and 1947 fallback transitions occurred at
1106 02:00 standard time, not 02:00 DST. (Thanks to Michael Deckers.)
1108 Pacific/Apia and Pacific/Pago_Pago switched from Antipodean to
1109 American time in 1892, not 1879. (Thanks to Michael Deckers.)
1111 Adjust the 1867 transition in Alaska to better reflect the
1112 historical record, by changing it to occur on 1867-10-18 at 15:30
1113 Sitka time rather than at the start of 1867-10-17 local time.
1114 Although strictly speaking this is accurate only for Sitka,
1115 the rest of Alaska's blanks need to be filled in somehow.
1117 Fix off-by-one errors in UT offsets for Adak and Nome before 1867.
1118 (Thanks to Michael Deckers.)
1120 Add 7 s to the UT offset in Asia/Yangon before 1920.
1122 Changes to zone names
1124 Remove Canada/East-Saskatchewan from the 'backward' file, as it
1125 exceeded the 14-character limit and was an unused misnomer anyway.
1127 Changes to build procedure
1129 To support applications that prefer to read time zone data in text
1130 form, two zic input files tzdata.zi and leapseconds are now
1131 installed by default. The commands 'zic tzdata.zi' and 'zic -L
1132 leapseconds tzdata.zi' can reproduce the tzdata binary files
1133 without and with leap seconds, respectively. To prevent these two
1134 new files from being installed, use 'make TZDATA_TEXT=', and to
1135 suppress leap seconds from the tzdata text installation, use 'make
1136 TZDATA_TEXT=tzdata.zi'.
1138 'make BACKWARD=' now suppresses backward-compatibility names
1139 like 'US/Pacific' that are defined in the 'backward' and
1142 'make check' now works on systems that lack a UTF-8 locale,
1143 or that lack the nsgmls program. Set UTF8_LOCALE to configure
1144 the name of a UTF-8 locale, if you have one.
1146 Y2K runtime checks are no longer enabled by default. Add
1147 -DDEPRECATE_TWO_DIGIT_YEARS to CFLAGS to enable them, instead of
1148 adding -DNO_RUN_TIME_WARNINGS_ABOUT_YEAR_2000_PROBLEMS_THANK_YOU
1149 to disable them. (New name suggested by Brian Inglis.)
1151 The build procedure for zdump now works on AIX 7.1.
1152 (Problem reported by Kees Dekker.)
1156 zic and the reference runtime now reject multiple leap seconds
1157 within 28 days of each other, or leap seconds before the Epoch.
1158 As a result, support for double leap seconds, which was
1159 obsolescent and undocumented, has been removed. Double leap
1160 seconds were an error in the C89 standard; they have never existed
1161 in civil timekeeping. (Thanks to Robert Elz and Bradley White for
1162 noticing glitches in the code that uncovered this problem.)
1164 zic now warns about use of the obsolescent and undocumented -y
1165 option, and about use of the obsolescent TYPE field of Rule lines.
1167 zic now allows unambiguous abbreviations like "Sa" and "Su" for
1168 weekdays; formerly it rejected them due to a bug. Conversely, zic
1169 no longer considers non-prefixes to be abbreviations; for example,
1170 it no longer accepts "lF" as an abbreviation for "lastFriday".
1171 Also, zic warns about the undocumented usage with a "last-"
1172 prefix, e.g., "last-Fri".
1174 Similarly, zic now accepts the unambiguous abbreviation "L" for
1175 "Link" in ordinary context and for "Leap" in leap-second context.
1176 Conversely, zic no longer accepts non-prefixes such as "La" as
1177 abbreviations for words like "Leap".
1179 zic no longer accepts leap second lines in ordinary input, or
1180 ordinary lines in leap second input. Formerly, zic sometimes
1181 warned about this undocumented usage and handled it incorrectly.
1183 The new macro HAVE_TZNAME governs whether the tzname external
1184 variable is exported, instead of USG_COMPAT. USG_COMPAT now
1185 governs only the external variables "timezone" and "daylight".
1186 This change is needed because the three variables are not in the
1187 same category: although POSIX requires tzname, it specifies the
1188 other two variables as optional. Also, USG_COMPAT is now 1 or 0:
1189 if not defined, the code attempts to guess it from other macros.
1191 localtime.c and difftime.c no longer require stdio.h, and .c files
1192 other than zic.c no longer require sys/wait.h.
1194 zdump.c no longer assumes snprintf. (Reported by Jonathan Leffler.)
1196 Calculation of time_t extrema works around a bug in GCC 4.8.4
1197 (Reported by Stan Shebs and Joseph Myers.)
1199 zic.c no longer mistranslates formats of line numbers in non-English
1200 locales. (Problem reported by Benno Schulenberg.)
1202 Several minor changes have been made to the code to make it a
1203 bit easier to port to MS-Windows and Solaris. (Thanks to Kees
1204 Dekker for reporting the problems.)
1206 Changes to documentation and commentary
1208 The two new files 'theory.html' and 'calendars' contain the
1209 contents of the removed file 'Theory'. The goal is to document
1210 tzdb theory more accessibly.
1212 The zic man page now documents abbreviation rules.
1214 tz-link.htm now covers how to apply tzdata changes to clients.
1215 (Thanks to Jorge Fábregas for the AIX link.) It also mentions MySQL.
1217 The leap-seconds.list URL has been updated to something that is
1218 more reliable for tzdb. (Thanks to Tim Parenti and Brian Inglis.)
1220 Release 2017b - 2017-03-17 07:30:38 -0700
1222 Briefly: Haiti has resumed DST.
1224 Changes to past and future timestamps
1226 Haiti resumed observance of DST in 2017. (Thanks to Steffen Thorsen.)
1228 Changes to past timestamps
1230 Liberia changed from -004430 to +00 on 1972-01-07, not 1972-05-01.
1232 Use "MMT" to abbreviate Liberia's time zone before 1972, as "-004430"
1233 is one byte over the POSIX limit. (Problem reported by Derick Rethans.)
1237 The reference localtime implementation now falls back on the
1238 current US daylight-saving transition rules rather than the
1239 1987-2006 rules. This fallback occurs only when (1) the TZ
1240 environment variable has a value like "AST4ADT" that asks
1241 for daylight saving time but does not specify the rules, (2) there
1242 is no file by that name, and (3) the TZDEFRULES file cannot be
1243 loaded. (Thanks to Tom Lane.)
1246 Release 2017a - 2017-02-28 00:05:36 -0800
1248 Briefly: Southern Chile moves from -04/-03 to -03, and Mongolia
1251 Changes to future timestamps
1253 Mongolia no longer observes DST. (Thanks to Ganbold Tsagaankhuu.)
1255 Chile's Region of Magallanes moves from -04/-03 to -03 year-round.
1256 Its clocks diverge from America/Santiago starting 2017-05-13 at
1257 23:00, hiving off a new zone America/Punta_Arenas. Although the
1258 Chilean government says this change expires in May 2019, for now
1259 assume it's permanent. (Thanks to Juan Correa and Deborah
1260 Goldsmith.) This also affects Antarctica/Palmer.
1262 Changes to past timestamps
1264 Fix many entries for historical timestamps for Europe/Madrid
1265 before 1979, to agree with tables compiled by Pere Planesas of the
1266 National Astronomical Observatory of Spain. As a side effect,
1267 this changes some timestamps for Africa/Ceuta before 1929, which
1268 are probably guesswork anyway. (Thanks to Steve Allen and
1269 Pierpaolo Bernardi for the heads-ups, and to Michael Deckers for
1270 correcting the 1901 transition.)
1272 Ecuador observed DST from 1992-11-28 to 1993-02-05.
1273 (Thanks to Alois Treindl.)
1275 Asia/Atyrau and Asia/Oral were at +03 (not +04) before 1930-06-21.
1276 (Thanks to Stepan Golosunov.)
1278 Changes to past and future time zone abbreviations
1280 Switch to numeric time zone abbreviations for South America, as
1281 part of the ongoing project of removing invented abbreviations.
1282 This avoids the need to invent an abbreviation for the new Chilean
1283 new zone. Similarly, switch from invented to numeric time zone
1284 abbreviations for Afghanistan, American Samoa, the Azores,
1285 Bangladesh, Bhutan, the British Indian Ocean Territory, Brunei,
1286 Cape Verde, Chatham Is, Christmas I, Cocos (Keeling) Is, Cook Is,
1287 Dubai, East Timor, Eucla, Fiji, French Polynesia, Greenland,
1288 Indochina, Iran, Iraq, Kiribati, Lord Howe, Macquarie, Malaysia,
1289 the Maldives, Marshall Is, Mauritius, Micronesia, Mongolia,
1290 Myanmar, Nauru, Nepal, New Caledonia, Niue, Norfolk I, Palau,
1291 Papua New Guinea, the Philippines, Pitcairn, Qatar, Réunion, St
1292 Pierre & Miquelon, Samoa, Saudi Arabia, Seychelles, Singapore,
1293 Solomon Is, Tokelau, Tuvalu, Wake, Vanuatu, Wallis & Futuna, and
1294 Xinjiang; for 20-minute daylight saving time in Ghana before 1943;
1295 for half-hour daylight saving time in Belize before 1944 and in
1296 the Dominican Republic before 1975; and for Canary Islands before
1297 1946, for Guinea-Bissau before 1975, for Iceland before 1969, for
1298 Indian Summer Time before 1942, for Indonesia before around 1964,
1299 for Kenya before 1960, for Liberia before 1973, for Madeira before
1300 1967, for Namibia before 1943, for the Netherlands in 1937-9, for
1301 Pakistan before 1971, for Western Sahara before 1977, and for
1302 Zaporozhye in 1880-1924.
1304 For Alaska time from 1900 through 1967, instead of "CAT" use the
1305 abbreviation "AST", the abbreviation commonly used at the time
1306 (Atlantic Standard Time had not been standardized yet). Use "AWT"
1307 and "APT" instead of the invented abbreviations "CAWT" and "CAPT".
1309 Use "CST" and "CDT" instead of invented abbreviations for Macau
1310 before 1999 and Taiwan before 1938, and use "JST" instead of the
1311 invented abbreviation "JCST" for Japan and Korea before 1938.
1313 Change to database entry category
1315 Move the Pacific/Johnston link from 'australasia' to 'backward',
1316 since Johnston is now uninhabited.
1320 zic no longer mishandles some transitions in January 2038 when it
1321 attempts to work around Qt bug 53071. This fixes a bug affecting
1322 Pacific/Tongatapu that was introduced in zic 2016e. localtime.c
1323 now contains a workaround, useful when loading a file generated by
1324 a buggy zic. (Problem and localtime.c fix reported by Bradley
1327 zdump -i now outputs non-hour numeric time zone abbreviations
1328 without a colon, e.g., "+0530" rather than "+05:30". This agrees
1329 with zic %z and with common practice, and simplifies auditing of
1332 zdump is now buildable again with -DUSE_LTZ=0.
1333 (Problem reported by Joseph Myers.)
1335 zdump.c now always includes private.h, to avoid code duplication
1336 with private.h. (Problem reported by Kees Dekker.)
1338 localtime.c no longer mishandles early or late timestamps
1339 when TZ is set to a POSIX-style string that specifies DST.
1340 (Problem reported by Kees Dekker.)
1342 date and strftime now cause %z to generate "-0000" instead of
1343 "+0000" when the UT offset is zero and the time zone abbreviation
1346 Changes to documentation and commentary
1348 The 'Theory' file now better documents choice of historical time
1349 zone abbreviations. (Problems reported by Michael Deckers.)
1351 tz-link.htm now covers leap smearing, which is popular in clouds.
1354 Release 2016j - 2016-11-22 23:17:13 -0800
1356 Briefly: Saratov, Russia moves from +03 to +04 on 2016-12-04.
1358 Changes to future timestamps
1360 Saratov, Russia switches from +03 to +04 on 2016-12-04 at 02:00.
1361 This hives off a new zone Europe/Saratov from Europe/Volgograd.
1362 (Thanks to Yuri Konotopov and Stepan Golosunov.)
1364 Changes to past timestamps
1366 The new zone Asia/Atyrau for Atyraū Region, Kazakhstan, is like
1367 Asia/Aqtau except it switched from +05/+06 to +04/+05 in spring
1368 1999, not fall 1994. (Thanks to Stepan Golosunov.)
1370 Changes to past time zone abbreviations
1372 Asia/Gaza and Asia/Hebron now use "EEST", not "EET", to denote
1373 summer time before 1948. The old use of "EET" was a typo.
1377 zic no longer mishandles file systems that lack hard links, fixing
1378 bugs introduced in 2016g. (Problems reported by Tom Lane.)
1379 Also, when the destination already contains symbolic links, zic
1380 should now work better on systems where the 'link' system call
1381 does not follow symbolic links.
1383 Changes to documentation and commentary
1385 tz-link.htm now documents the relationship between release version
1386 numbers and development-repository commit tags. (Suggested by
1389 The 'Theory' file now documents UT.
1391 iso3166.tab now accents "Curaçao", and commentary now mentions
1392 the names "Cabo Verde" and "Czechia". (Thanks to Jiří Boháč.)
1395 Release 2016i - 2016-11-01 23:19:52 -0700
1397 Briefly: Cyprus split into two time zones on 2016-10-30, and Tonga
1398 reintroduces DST on 2016-11-06.
1400 Changes to future timestamps
1402 Pacific/Tongatapu begins DST on 2016-11-06 at 02:00, ending on
1403 2017-01-15 at 03:00. Assume future observances in Tonga will be
1404 from the first Sunday in November through the third Sunday in
1405 January, like Fiji. (Thanks to Pulu ʻAnau.) Switch to numeric
1406 time zone abbreviations for this zone.
1408 Changes to past and future timestamps
1410 Northern Cyprus is now +03 year round, causing a split in Cyprus
1411 time zones starting 2016-10-30 at 04:00. This creates a zone
1412 Asia/Famagusta. (Thanks to Even Scharning and Matt Johnson.)
1414 Antarctica/Casey switched from +08 to +11 on 2016-10-22.
1415 (Thanks to Steffen Thorsen.)
1417 Changes to past timestamps
1419 Several corrections were made for pre-1975 timestamps in Italy.
1420 These affect Europe/Malta, Europe/Rome, Europe/San_Marino, and
1423 First, the 1893-11-01 00:00 transition in Italy used the new UT
1424 offset (+01), not the old (+00:49:56). (Thanks to Michael
1427 Second, rules for daylight saving in Italy were changed to agree
1428 with Italy's National Institute of Metrological Research (INRiM)
1429 except for 1944, as follows (thanks to Pierpaolo Bernardi, Brian
1430 Inglis, and Michael Deckers):
1432 The 1916-06-03 transition was at 24:00, not 00:00.
1434 The 1916-10-01, 1919-10-05, and 1920-09-19 transitions were at
1437 The 1917-09-30 and 1918-10-06 transitions were at 24:00, not
1440 The 1944-09-17 transition was at 03:00, not 01:00. This
1441 particular change is taken from Italian law as INRiM's table,
1442 (which says 02:00) appears to have a typo here. Also, keep the
1443 1944-04-03 transition for Europe/Rome, as Rome was controlled by
1446 The 1967-1970 and 1972-1974 fallback transitions were at 01:00,
1451 The code should now be buildable on AmigaOS merely by setting the
1452 appropriate Makefile variables. (From a patch by Carsten Larsen.)
1455 Release 2016h - 2016-10-19 23:17:57 -0700
1457 Changes to future timestamps
1459 Asia/Gaza and Asia/Hebron end DST on 2016-10-29 at 01:00, not
1460 2016-10-21 at 00:00. (Thanks to Sharef Mustafa.) Predict that
1461 future fall transitions will be on the last Saturday of October
1462 at 01:00, which is consistent with predicted spring transitions
1463 on the last Saturday of March. (Thanks to Tim Parenti.)
1465 Changes to past timestamps
1467 In Turkey, transitions in 1986-1990 were at 01:00 standard time
1468 not at 02:00, and the spring 1994 transition was on March 20, not
1469 March 27. (Thanks to Kıvanç Yazan.)
1471 Changes to past and future time zone abbreviations
1473 Asia/Colombo now uses numeric time zone abbreviations like "+0530"
1474 instead of alphabetic ones like "IST" and "LKT". Various
1475 English-language sources use "IST", "LKT" and "SLST", with no
1476 working consensus. (Usage of "SLST" mentioned by Sadika
1481 zic no longer mishandles relativizing file names when creating
1482 symbolic links like /etc/localtime, when these symbolic links
1483 are outside the usual directory hierarchy. This fixes a bug
1484 introduced in 2016g. (Problem reported by Andreas Stieger.)
1486 Changes to build procedure
1488 New rules 'traditional_tarballs' and 'traditional_signatures' for
1489 building just the traditional-format distribution. (Requested by
1492 The file 'version' is now put into the tzdata tarball too.
1493 (Requested by Howard Hinnant.)
1495 Changes to documentation and commentary
1497 The 'Theory' file now has a section on interface stability.
1498 (Requested by Paul Koning.) It also mentions features like
1499 tm_zone and localtime_rz that have long been supported by the
1502 tz-link.htm has improved coverage of time zone boundaries suitable
1503 for geolocation. (Thanks to heads-ups from Evan Siroky and Matt
1506 The US commentary now mentions Allen and the "day of two noons".
1508 The Fiji commentary mentions the government's 2016-10-03 press
1509 release. (Thanks to Raymond Kumar.)
1512 Release 2016g - 2016-09-13 08:56:38 -0700
1514 Changes to future timestamps
1516 Turkey switched from EET/EEST (+02/+03) to permanent +03,
1517 effective 2016-09-07. (Thanks to Burak AYDIN.) Use "+03" rather
1518 than an invented abbreviation for the new time.
1520 New leap second 2016-12-31 23:59:60 UTC as per IERS Bulletin C 52.
1521 (Thanks to Tim Parenti.)
1523 Changes to past timestamps
1525 For America/Los_Angeles, spring-forward transition times have been
1526 corrected from 02:00 to 02:01 in 1948, and from 02:00 to 01:00 in
1529 For zones using Soviet time on 1919-07-01, transitions to UT-based
1530 time were at 00:00 UT, not at 02:00 local time. The affected
1531 zones are Europe/Kirov, Europe/Moscow, Europe/Samara, and
1532 Europe/Ulyanovsk. (Thanks to Alexander Belopolsky.)
1534 Changes to past and future time zone abbreviations
1536 The Factory zone now uses the time zone abbreviation -00 instead
1537 of a long English-language string, as -00 is now the normal way to
1538 represent an undefined time zone.
1540 Several zones in Antarctica and the former Soviet Union, along
1541 with zones intended for ships at sea that cannot use POSIX TZ
1542 strings, now use numeric time zone abbreviations instead of
1543 invented or obsolete alphanumeric abbreviations. The affected
1544 zones are Antarctica/Casey, Antarctica/Davis,
1545 Antarctica/DumontDUrville, Antarctica/Mawson, Antarctica/Rothera,
1546 Antarctica/Syowa, Antarctica/Troll, Antarctica/Vostok,
1547 Asia/Anadyr, Asia/Ashgabat, Asia/Baku, Asia/Bishkek, Asia/Chita,
1548 Asia/Dushanbe, Asia/Irkutsk, Asia/Kamchatka, Asia/Khandyga,
1549 Asia/Krasnoyarsk, Asia/Magadan, Asia/Omsk, Asia/Sakhalin,
1550 Asia/Samarkand, Asia/Srednekolymsk, Asia/Tashkent, Asia/Tbilisi,
1551 Asia/Ust-Nera, Asia/Vladivostok, Asia/Yakutsk, Asia/Yekaterinburg,
1552 Asia/Yerevan, Etc/GMT-14, Etc/GMT-13, Etc/GMT-12, Etc/GMT-11,
1553 Etc/GMT-10, Etc/GMT-9, Etc/GMT-8, Etc/GMT-7, Etc/GMT-6, Etc/GMT-5,
1554 Etc/GMT-4, Etc/GMT-3, Etc/GMT-2, Etc/GMT-1, Etc/GMT+1, Etc/GMT+2,
1555 Etc/GMT+3, Etc/GMT+4, Etc/GMT+5, Etc/GMT+6, Etc/GMT+7, Etc/GMT+8,
1556 Etc/GMT+9, Etc/GMT+10, Etc/GMT+11, Etc/GMT+12, Europe/Kaliningrad,
1557 Europe/Minsk, Europe/Samara, Europe/Volgograd, and
1558 Indian/Kerguelen. For Europe/Moscow the invented abbreviation MSM
1559 was replaced by +05, whereas MSK and MSD were kept as they are not
1560 our invention and are widely used.
1562 Changes to zone names
1564 Rename Asia/Rangoon to Asia/Yangon, with a backward compatibility link.
1565 (Thanks to David Massoud.)
1569 zic no longer generates binary files containing POSIX TZ-like
1570 strings that disagree with the local time type after the last
1571 explicit transition in the data. This fixes a bug with
1572 Africa/Casablanca and Africa/El_Aaiun in some year-2037 timestamps
1573 on the reference platform. (Thanks to Alexander Belopolsky for
1574 reporting the bug and suggesting a way forward.)
1576 If the installed localtime and/or posixrules files are symbolic
1577 links, zic now keeps them symbolic links when updating them, for
1578 compatibility with platforms like OpenSUSE where other programs
1579 configure these files as symlinks.
1581 zic now avoids hard linking to symbolic links, avoids some
1582 unnecessary mkdir and stat system calls, and uses shorter file
1585 zdump has a new -i option to generate transitions in a
1586 more-compact but still human-readable format. This option is
1587 experimental, and the output format may change in future versions.
1588 (Thanks to Jon Skeet for suggesting that an option was needed,
1589 and thanks to Tim Parenti and Chris Rovick for further comments.)
1591 Changes to build procedure
1593 An experimental distribution format is available, in addition
1594 to the traditional format which will continue to be distributed.
1595 The new format is a tarball tzdb-VERSION.tar.lz with signature
1596 file tzdb-VERSION.tar.lz.asc. It unpacks to a top-level directory
1597 tzdb-VERSION containing the code and data of the traditional
1598 two-tarball format, along with extra data that may be useful.
1599 (Thanks to Antonio Diaz Diaz, Oscar van Vlijmen, and many others
1600 for comments about the experimental format.)
1602 The release version number is now more accurate in the usual case
1603 where releases are built from a Git repository. For example, if
1604 23 commits and some working-file changes have been made since
1605 release 2016g, the version number is now something like
1606 '2016g-23-g50556e3-dirty' instead of the misleading '2016g'.
1607 Tagged releases use the same version number format as before,
1608 e.g., '2016g'. To support the more-accurate version number, its
1609 specification has moved from a line in the Makefile to a new
1610 source file 'version'.
1612 The experimental distribution contains a file to2050.tzs that
1613 contains what should be the output of 'zdump -i -c 2050' on
1614 primary zones. If this file is available, 'make check' now checks
1615 that zdump generates this output.
1617 'make check_web' now works on Fedora-like distributions.
1619 Changes to documentation and commentary
1621 tzfile.5 now documents the new restriction on POSIX TZ-like
1622 strings that is now implemented by zic.
1624 Comments now cite URLs for some 1917-1921 Russian DST decrees.
1625 (Thanks to Alexander Belopolsky.)
1627 tz-link.htm mentions JuliaTime (thanks to Curtis Vogt) and Time4J
1628 (thanks to Meno Hochschild) and ThreeTen-Extra, and its
1629 description of Java 8 has been brought up to date (thanks to
1630 Stephen Colebourne). Its description of local time on Mars has
1631 been updated to match current practice, and URLs have been updated
1632 and some obsolete ones removed.
1635 Release 2016f - 2016-07-05 16:26:51 +0200
1637 Changes affecting future timestamps
1639 The Egyptian government changed its mind on short notice, and
1640 Africa/Cairo will not introduce DST starting 2016-07-07 after all.
1641 (Thanks to Mina Samuel.)
1643 Asia/Novosibirsk switches from +06 to +07 on 2016-07-24 at 02:00.
1644 (Thanks to Stepan Golosunov.)
1646 Changes to past and future timestamps
1648 Asia/Novokuznetsk and Asia/Novosibirsk now use numeric time zone
1649 abbreviations instead of invented ones.
1651 Changes affecting past timestamps
1653 Europe/Minsk's 1992-03-29 spring-forward transition was at 02:00 not 00:00.
1654 (Thanks to Stepan Golosunov.)
1657 Release 2016e - 2016-06-14 08:46:16 -0700
1659 Changes affecting future timestamps
1661 Africa/Cairo observes DST in 2016 from July 7 to the end of October.
1662 Guess October 27 and 24:00 transitions. (Thanks to Steffen Thorsen.)
1663 For future years, guess April's last Thursday to October's last
1664 Thursday except for Ramadan.
1666 Changes affecting past timestamps
1668 Locations while uninhabited now use '-00', not 'zzz', as a
1669 placeholder time zone abbreviation. This is inspired by Internet
1670 RFC 3339 and is more consistent with numeric time zone
1671 abbreviations already used elsewhere. The change affects several
1672 arctic and antarctic locations, e.g., America/Cambridge_Bay before
1673 1920 and Antarctica/Troll before 2005.
1675 Asia/Baku's 1992-09-27 transition from +04 (DST) to +04 (non-DST) was
1676 at 03:00, not 23:00 the previous day. (Thanks to Michael Deckers.)
1680 zic now outputs a dummy transition at time 2**31 - 1 in zones
1681 whose POSIX-style TZ strings contain a '<'. This mostly works
1682 around Qt bug 53071 <https://bugreports.qt.io/browse/QTBUG-53071>.
1683 (Thanks to Zhanibek Adilbekov for reporting the Qt bug.)
1685 Changes affecting documentation and commentary
1687 tz-link.htm says why governments should give plenty of notice for
1688 time zone or DST changes, and refers to Matt Johnson's blog post.
1690 tz-link.htm mentions Tzdata for Elixir. (Thanks to Matt Johnson.)
1693 Release 2016d - 2016-04-17 22:50:29 -0700
1695 Changes affecting future timestamps
1697 America/Caracas switches from -0430 to -04 on 2016-05-01 at 02:30.
1698 (Thanks to Alexander Krivenyshev for the heads-up.)
1700 Asia/Magadan switches from +10 to +11 on 2016-04-24 at 02:00.
1701 (Thanks to Alexander Krivenyshev and Matt Johnson.)
1703 New zone Asia/Tomsk, split off from Asia/Novosibirsk. It covers
1704 Tomsk Oblast, Russia, which switches from +06 to +07 on 2016-05-29
1705 at 02:00. (Thanks to Stepan Golosunov.)
1707 Changes affecting past timestamps
1709 New zone Europe/Kirov, split off from Europe/Volgograd. It covers
1710 Kirov Oblast, Russia, which switched from +04/+05 to +03/+04 on
1711 1989-03-26 at 02:00, roughly a year after Europe/Volgograd made
1712 the same change. (Thanks to Stepan Golosunov.)
1714 Russia and nearby locations had daylight-saving transitions on
1715 1992-03-29 at 02:00 and 1992-09-27 at 03:00, instead of on
1716 1992-03-28 at 23:00 and 1992-09-26 at 23:00. (Thanks to Stepan
1719 Many corrections to historical time in Kazakhstan from 1991
1720 through 2005. (Thanks to Stepan Golosunov.) Replace Kazakhstan's
1721 invented time zone abbreviations with numeric abbreviations.
1723 Changes to commentary
1725 Mention Internet RFCs 7808 (TZDIST) and 7809 (CalDAV time zone references).
1728 Release 2016c - 2016-03-23 00:51:27 -0700
1730 Changes affecting future timestamps
1732 Azerbaijan no longer observes DST. (Thanks to Steffen Thorsen.)
1734 Chile reverts from permanent to seasonal DST. (Thanks to Juan
1735 Correa for the heads-up, and to Tim Parenti for corrections.)
1736 Guess that future transitions are August's and May's second
1737 Saturdays at 24:00 mainland time. Also, call the period from
1738 2014-09-07 through 2016-05-14 daylight saving time instead of
1739 standard time, as that seems more appropriate now.
1741 Changes affecting past timestamps
1743 Europe/Kaliningrad and Europe/Vilnius changed from +03/+04 to
1744 +02/+03 on 1989-03-26, not 1991-03-31. Europe/Volgograd changed
1745 from +04/+05 to +03/+04 on 1988-03-27, not 1989-03-26.
1746 (Thanks to Stepan Golosunov.)
1748 Changes to commentary
1750 Several updates and URLs for historical and proposed Russian changes.
1751 (Thanks to Stepan Golosunov, Matt Johnson, and Alexander Krivenyshev.)
1754 Release 2016b - 2016-03-12 17:30:14 -0800
1758 Starting with release 2016b, some data entries cause zic implementations
1759 derived from tz releases 2005j through 2015e to issue warnings like
1760 "time zone abbreviation differs from POSIX standard (+03)".
1761 These warnings should not otherwise affect zic's output and can safely be
1762 ignored on today's platforms, as the warnings refer to a restriction in
1763 POSIX.1-1988 that was removed in POSIX.1-2001. One way to suppress the
1764 warnings is to upgrade to zic derived from tz releases 2015f and later.
1766 Changes affecting future timestamps
1768 New zones Europe/Astrakhan and Europe/Ulyanovsk for Astrakhan and
1769 Ulyanovsk Oblasts, Russia, both of which will switch from +03 to +04 on
1770 2016-03-27 at 02:00 local time. They need distinct zones since their
1771 post-1970 histories disagree. New zone Asia/Barnaul for Altai Krai and
1772 Altai Republic, Russia, which will switch from +06 to +07 on the same date
1773 and local time. The Astrakhan change is already official; the others have
1774 passed the first reading in the State Duma and are extremely likely.
1775 Also, Asia/Sakhalin moves from +10 to +11 on 2016-03-27 at 02:00.
1776 (Thanks to Alexander Krivenyshev for the heads-up, and to Matt Johnson
1777 and Stepan Golosunov for followup.)
1779 As a trial of a new system that needs less information to be made up,
1780 the new zones use numeric time zone abbreviations like "+04"
1781 instead of invented abbreviations like "ASTT".
1783 Haiti will not observe DST in 2016. (Thanks to Jean Antoine via
1786 Palestine's spring-forward transition on 2016-03-26 is at 01:00, not 00:00.
1787 (Thanks to Hannah Kreitem.) Guess future transitions will be March's last
1788 Saturday at 01:00, not March's last Friday at 24:00.
1790 Changes affecting past timestamps
1792 Europe/Chisinau observed DST during 1990, and switched from +04 to
1793 +03 at 1990-05-06 02:00, instead of switching from +03 to +02.
1794 (Thanks to Stepan Golosunov.)
1796 1991 abbreviations in Europe/Samara should be SAMT/SAMST, not
1797 KUYT/KUYST. (Thanks to Stepan Golosunov.)
1801 tzselect's diagnostics and checking, and checktab.awk's checking,
1802 have been improved. (Thanks to J William Piggott.)
1804 tzcode now builds under MinGW. (Thanks to Ian Abbott and Esben Haabendal.)
1806 tzselect now tests Julian-date TZ settings more accurately.
1807 (Thanks to J William Piggott.)
1809 Changes to commentary
1811 Comments in zone tables have been improved. (Thanks to J William Piggott.)
1813 tzselect again limits its menu comments so that menus fit on a
1814 24×80 alphanumeric display.
1816 A new web page tz-how-to.html. (Thanks to Bill Seymour.)
1818 In the Theory file, the description of possible time zone abbreviations in
1819 tzdata has been cleaned up, as the old description was unclear and
1820 inconsistent. (Thanks to Alain Mouette for reporting the problem.)
1823 Release 2016a - 2016-01-26 23:28:02 -0800
1825 Changes affecting future timestamps
1827 America/Cayman will not observe daylight saving this year after all.
1828 Revert our guess that it would. (Thanks to Matt Johnson.)
1830 Asia/Chita switches from +0800 to +0900 on 2016-03-27 at 02:00.
1831 (Thanks to Alexander Krivenyshev.)
1833 Asia/Tehran now has DST predictions for the year 2038 and later,
1834 to be March 21 00:00 to September 21 00:00. This is likely better
1835 than predicting no DST, albeit off by a day every now and then.
1837 Changes affecting past and future timestamps
1839 America/Metlakatla switched from PST all year to AKST/AKDT on
1840 2015-11-01 at 02:00. (Thanks to Steffen Thorsen.)
1842 America/Santa_Isabel has been removed, and replaced with a
1843 backward compatibility link to America/Tijuana. Its contents were
1844 apparently based on a misreading of Mexican legislation.
1846 Changes affecting past timestamps
1848 Asia/Karachi's two transition times in 2002 were off by a minute.
1849 (Thanks to Matt Johnson.)
1851 Changes affecting build procedure
1853 An installer can now combine leap seconds with use of the backzone file,
1854 e.g., with 'make PACKRATDATA=backzone REDO=posix_right zones'.
1855 The old 'make posix_packrat' rule is now marked as obsolescent.
1856 (Thanks to Ian Abbott for an initial implementation.)
1858 Changes affecting documentation and commentary
1860 A new file LICENSE makes it easier to see that the code and data
1861 are mostly public-domain. (Thanks to James Knight.) The three
1862 non-public-domain files now use the current (3-clause) BSD license
1863 instead of older versions of that license.
1865 tz-link.htm mentions the BDE library (thanks to Andrew Paprocki),
1866 CCTZ (thanks to Tim Parenti), TimeJones.com, and has a new section
1867 on editing tz source files (with a mention of Sublime zoneinfo,
1868 thanks to Gilmore Davidson).
1870 The Theory and asia files now mention the 2015 book "The Global
1871 Transformation of Time, 1870-1950", and cite a couple of reviews.
1873 The America/Chicago entry now documents the informal use of US
1874 central time in Fort Pierre, South Dakota. (Thanks to Rick
1875 McDermid, Matt Johnson, and Steve Jones.)
1878 Release 2015g - 2015-10-01 00:39:51 -0700
1880 Changes affecting future timestamps
1882 Turkey's 2015 fall-back transition is scheduled for Nov. 8, not Oct. 25.
1885 Norfolk moves from +1130 to +1100 on 2015-10-04 at 02:00 local time.
1886 (Thanks to Alexander Krivenyshev.)
1888 Fiji's 2016 fall-back transition is scheduled for January 17, not 24.
1889 (Thanks to Ken Rylander.)
1891 Fort Nelson, British Columbia will not fall back on 2015-11-01. It has
1892 effectively been on MST (-0700) since it advanced its clocks on 2015-03-08.
1893 New zone America/Fort_Nelson. (Thanks to Matt Johnson.)
1895 Changes affecting past timestamps
1897 Norfolk observed DST from 1974-10-27 02:00 to 1975-03-02 02:00.
1899 Changes affecting code
1901 localtime no longer mishandles America/Anchorage after 2037.
1902 (Thanks to Bradley White for reporting the bug.)
1904 On hosts with signed 32-bit time_t, localtime no longer mishandles
1905 Pacific/Fiji after 2038-01-16 14:00 UTC.
1907 The localtime module allows the variables 'timezone', 'daylight',
1908 and 'altzone' to be in common storage shared with other modules,
1909 and declares them in case the system <time.h> does not.
1910 (Problems reported by Kees Dekker.)
1912 On platforms with tm_zone, strftime.c now assumes it is not NULL.
1913 This simplifies the code and is consistent with zdump.c.
1914 (Problem reported by Christos Zoulas.)
1916 Changes affecting documentation
1918 The tzfile man page now documents that transition times denote the
1919 starts (not the ends) of the corresponding time periods.
1920 (Ambiguity reported by Bill Seymour.)
1923 Release 2015f - 2015-08-10 18:06:56 -0700
1925 Changes affecting future timestamps
1927 North Korea switches to +0830 on 2015-08-15. (Thanks to Steffen Thorsen.)
1928 The abbreviation remains "KST". (Thanks to Robert Elz.)
1930 Uruguay no longer observes DST. (Thanks to Steffen Thorsen
1933 Changes affecting past and future timestamps
1935 Moldova starts and ends DST at 00:00 UTC, not at 01:00 UTC.
1936 (Thanks to Roman Tudos.)
1938 Changes affecting data format and code
1940 zic's '-y YEARISTYPE' option is no longer documented. The TYPE
1941 field of a Rule line should now be '-'; the old values 'even',
1942 'odd', 'uspres', 'nonpres', 'nonuspres' were already undocumented.
1943 Although the implementation has not changed, these features do not
1944 work in the default installation, they are not used in the data,
1945 and they are now considered obsolescent.
1947 zic now checks that two rules don't take effect at the same time.
1948 (Thanks to Jon Skeet and Arthur David Olson.) Constraints on
1949 simultaneity are now documented.
1951 The two characters '%z' in a zone format now stand for the UT
1952 offset, e.g., '-07' for seven hours behind UT and '+0530' for
1953 five hours and thirty minutes ahead. This better supports time
1954 zone abbreviations conforming to POSIX.1-2001 and later.
1956 Changes affecting installed data files
1958 Comments for America/Halifax and America/Glace_Bay have been improved.
1959 (Thanks to Brian Inglis.)
1961 Data entries have been simplified for Atlantic/Canary, Europe/Simferopol,
1962 Europe/Sofia, and Europe/Tallinn. This yields slightly smaller
1963 installed data files for Europe/Simferopol and Europe/Tallinn.
1964 It does not affect timestamps. (Thanks to Howard Hinnant.)
1966 Changes affecting code
1968 zdump and zic no longer warn about valid time zone abbreviations
1971 Some Visual Studio 2013 warnings have been suppressed.
1972 (Thanks to Kees Dekker.)
1974 'date' no longer sets the time of day and its -a, -d, -n and -t
1975 options have been removed. Long obsolescent, the implementation
1976 of these features had porting problems. Builders no longer need
1977 to configure HAVE_ADJTIME, HAVE_SETTIMEOFDAY, or HAVE_UTMPX_H.
1978 (Thanks to Kees Dekker for pointing out the problem.)
1980 Changes affecting documentation
1982 The Theory file mentions naming issues earlier, as these seem to be
1983 poorly publicized (thanks to Gilmore Davidson for reporting the problem).
1985 tz-link.htm mentions Time Zone Database Parser (thanks to Howard Hinnant).
1987 Mention that Herbert Samuel introduced the term "Summer Time".
1990 Release 2015e - 2015-06-13 10:56:02 -0700
1992 Changes affecting future timestamps
1994 Morocco will suspend DST from 2015-06-14 03:00 through 2015-07-19 02:00,
1995 not 06-13 and 07-18 as we had guessed. (Thanks to Milamber.)
1997 Assume Cayman Islands will observe DST starting next year, using US rules.
1998 Although it isn't guaranteed, it is the most likely.
2000 Changes affecting data format
2002 The file 'iso3166.tab' now uses UTF-8, so that its entries can better
2003 spell the names of Åland Islands, Côte d'Ivoire, and Réunion.
2005 Changes affecting code
2007 When displaying data, tzselect converts it to the current locale's
2008 encoding if the iconv command works. (Problem reported by random832.)
2010 tzselect no longer mishandles Dominica, fixing a bug introduced
2011 in Release 2014f. (Problem reported by Owen Leibman.)
2013 zic -l no longer fails when compiled with -DTZDEFAULT=\"/etc/localtime\".
2014 This fixes a bug introduced in Release 2014f.
2015 (Problem reported by Leonardo Chiquitto.)
2018 Release 2015d - 2015-04-24 08:09:46 -0700
2020 Changes affecting future timestamps
2022 Egypt will not observe DST in 2015 and will consider canceling it
2023 permanently. For now, assume no DST indefinitely.
2024 (Thanks to Ahmed Nazmy and Tim Parenti.)
2026 Changes affecting past timestamps
2028 America/Whitehorse switched from UT -09 to -08 on 1967-05-28, not
2029 1966-07-01. Also, Yukon's time zone history is documented better.
2030 (Thanks to Brian Inglis and Dennis Ferguson.)
2032 Change affecting past and future time zone abbreviations
2034 The abbreviations for Hawaii-Aleutian standard and daylight times
2035 have been changed from HAST/HADT to HST/HDT, as per US Government
2036 Printing Office style. This affects only America/Adak since 1983,
2037 as America/Honolulu was already using the new style.
2039 Changes affecting code
2041 zic has some minor performance improvements.
2044 Release 2015c - 2015-04-11 08:55:55 -0700
2046 Changes affecting future timestamps
2048 Egypt's spring-forward transition is at 24:00 on April's last Thursday,
2049 not 00:00 on April's last Friday. 2015's transition will therefore be on
2050 Thursday, April 30 at 24:00, not Friday, April 24 at 00:00. Similar fixes
2051 apply to 2026, 2037, 2043, etc. (Thanks to Steffen Thorsen.)
2053 Changes affecting past timestamps
2055 The following changes affect some pre-1991 Chile-related timestamps
2056 in America/Santiago, Antarctica/Palmer, and Pacific/Easter.
2058 The 1910 transition was January 10, not January 1.
2060 The 1918 transition was September 10, not September 1.
2062 The UT -04 time observed from 1932 to 1942 is now considered to
2063 be standard time, not year-round DST.
2065 Santiago observed DST (UT -03) from 1946-07-15 through
2066 1946-08-31, then reverted to standard time, then switched to -05
2069 Assume transitions before 1968 were at 00:00, since we have no data
2072 The spring 1988 transition was 1988-10-09, not 1988-10-02.
2073 The fall 1990 transition was 1990-03-11, not 1990-03-18.
2075 Assume no UT offset change for Pacific/Easter on 1890-01-01,
2076 and omit all transitions on Pacific/Easter from 1942 through 1946
2077 since we have no data suggesting that they existed.
2079 One more zone has been turned into a link, as it differed
2080 from an existing zone only for older timestamps. As usual,
2081 this change affects UT offsets in pre-1970 timestamps only.
2082 The zone's old contents have been moved to the 'backzone' file.
2083 The affected zone is America/Montreal.
2085 Changes affecting commentary
2087 Mention the TZUpdater tool.
2089 Mention "The Time Now". (Thanks to Brandon Ramsey.)
2092 Release 2015b - 2015-03-19 23:28:11 -0700
2094 Changes affecting future timestamps
2096 Mongolia will start observing DST again this year, from the last
2097 Saturday in March at 02:00 to the last Saturday in September at 00:00.
2098 (Thanks to Ganbold Tsagaankhuu.)
2100 Palestine will start DST on March 28, not March 27. Also,
2101 correct the fall 2014 transition from September 26 to October 24.
2102 Adjust future predictions accordingly. (Thanks to Steffen Thorsen.)
2104 Changes affecting past timestamps
2106 The 1982 zone shift in Pacific/Easter has been corrected, fixing a 2015a
2107 regression. (Thanks to Stuart Bishop for reporting the problem.)
2109 Some more zones have been turned into links, when they differed
2110 from existing zones only for older timestamps. As usual,
2111 these changes affect UT offsets in pre-1970 timestamps only.
2112 Their old contents have been moved to the 'backzone' file.
2113 The affected zones are: America/Antigua, America/Cayman,
2114 Pacific/Midway, and Pacific/Saipan.
2116 Changes affecting time zone abbreviations
2118 Correct the 1992-2010 DST abbreviation in Volgograd from "MSK" to "MSD".
2121 Changes affecting code
2123 Fix integer overflow bug in reference 'mktime' implementation.
2124 (Problem reported by Jörg Richter.)
2126 Allow -Dtime_tz=time_t compilations, and allow -Dtime_tz=... libraries
2127 to be used in the same executable as standard-library time_t functions.
2128 (Problems reported by Bradley White.)
2130 Changes affecting commentary
2132 Cite the recent Mexican decree changing Quintana Roo's time zone.
2133 (Thanks to Carlos Raúl Perasso.)
2135 Likewise for the recent Chilean decree. (Thanks to Eduardo Romero Urra.)
2137 Update info about Mars time.
2140 Release 2015a - 2015-01-29 22:35:20 -0800
2142 Changes affecting future timestamps
2144 The Mexican state of Quintana Roo, represented by America/Cancun,
2145 will shift from Central Time with DST to Eastern Time without DST
2146 on 2015-02-01 at 02:00. (Thanks to Steffen Thorsen and Gwillim Law.)
2148 Chile will not change clocks in April or thereafter; its new standard time
2149 will be its old daylight saving time. This affects America/Santiago,
2150 Pacific/Easter, and Antarctica/Palmer. (Thanks to Juan Correa.)
2152 New leap second 2015-06-30 23:59:60 UTC as per IERS Bulletin C 49.
2153 (Thanks to Tim Parenti.)
2155 Changes affecting past timestamps
2157 Iceland observed DST in 1919 and 1921, and its 1939 fallback
2158 transition was Oct. 29, not Nov. 29. Remove incorrect data from
2159 Shanks about time in Iceland between 1837 and 1908.
2161 Some more zones have been turned into links, when they differed
2162 from existing zones only for older timestamps. As usual,
2163 these changes affect UT offsets in pre-1970 timestamps only.
2164 Their old contents have been moved to the 'backzone' file.
2165 The affected zones are: Asia/Aden, Asia/Bahrain, Asia/Kuwait,
2168 Changes affecting code
2170 tzalloc now scrubs time zone abbreviations compatibly with the way
2171 that tzset always has, by replacing invalid bytes with '_' and by
2172 shortening too-long abbreviations.
2174 tzselect ports to POSIX awk implementations, no longer mishandles
2175 POSIX TZ settings when GNU awk is used, and reports POSIX TZ
2176 settings to the user. (Thanks to Stefan Kuhn.)
2178 Changes affecting build procedure
2180 'make check' now checks for links to links in the data.
2181 One such link (for Africa/Asmera) has been fixed.
2182 (Thanks to Stephen Colebourne for pointing out the problem.)
2184 Changes affecting commentary
2186 The leapseconds file commentary now mentions the expiration date.
2187 (Problem reported by Martin Burnicki.)
2189 Update Mexican Library of Congress URL.
2192 Release 2014j - 2014-11-10 17:37:11 -0800
2194 Changes affecting current and future timestamps
2196 Turks & Caicos' switch from US eastern time to UT -04 year-round
2197 did not occur on 2014-11-02 at 02:00. It's currently scheduled
2198 for 2015-11-01 at 02:00. (Thanks to Chris Walton.)
2200 Changes affecting past timestamps
2202 Many pre-1989 timestamps have been corrected for Asia/Seoul and
2203 Asia/Pyongyang, based on sources for the Korean-language Wikipedia
2204 entry for time in Korea. (Thanks to Sanghyuk Jung.) Also, no
2205 longer guess that Pyongyang mimicked Seoul time after World War II,
2206 as this is politically implausible.
2208 Some more zones have been turned into links, when they differed
2209 from existing zones only for older timestamps. As usual,
2210 these changes affect UT offsets in pre-1970 timestamps only.
2211 Their old contents have been moved to the 'backzone' file.
2212 The affected zones are: Africa/Addis_Ababa, Africa/Asmara,
2213 Africa/Dar_es_Salaam, Africa/Djibouti, Africa/Kampala,
2214 Africa/Mogadishu, Indian/Antananarivo, Indian/Comoro, and
2217 Changes affecting commentary
2219 The commentary is less enthusiastic about Shanks as a source,
2220 and is more careful to distinguish UT from UTC.
2223 Release 2014i - 2014-10-21 22:04:57 -0700
2225 Changes affecting future timestamps
2227 Pacific/Fiji will observe DST from 2014-11-02 02:00 to 2015-01-18 03:00.
2228 (Thanks to Ken Rylander for the heads-up.) Guess that future
2229 years will use a similar pattern.
2231 A new Zone Pacific/Bougainville, for the part of Papua New Guinea
2232 that plans to switch from UT +10 to +11 on 2014-12-28 at 02:00.
2233 (Thanks to Kiley Walbom for the heads-up.)
2235 Changes affecting time zone abbreviations
2237 Since Belarus is not changing its clocks even though Moscow is,
2238 the time zone abbreviation in Europe/Minsk is changing from FET
2239 to its more-traditional value MSK on 2014-10-26 at 01:00.
2240 (Thanks to Alexander Bokovoy for the heads-up about Belarus.)
2242 The new abbreviation IDT stands for the pre-1976 use of UT +08 in
2243 Indochina, to distinguish it better from ICT (+07).
2245 Changes affecting past timestamps
2247 Many timestamps have been corrected for Asia/Ho_Chi_Minh before 1976
2248 (thanks to Trần Ngọc Quân for an indirect pointer to Trần Tiến Bình's
2249 authoritative book). Asia/Ho_Chi_Minh has been added to
2250 zone1970.tab, to give tzselect users in Vietnam two choices,
2251 since north and south Vietnam disagreed after our 1970 cutoff.
2253 Asia/Phnom_Penh and Asia/Vientiane have been turned into links, as
2254 they differed from existing zones only for older timestamps. As
2255 usual, these changes affect pre-1970 timestamps only. Their old
2256 contents have been moved to the 'backzone' file.
2258 Changes affecting code
2260 The time-related library functions now set errno on failure, and
2261 some crashes in the new tzalloc-related library functions have
2262 been fixed. (Thanks to Christos Zoulas for reporting most of
2263 these problems and for suggesting fixes.)
2265 If USG_COMPAT is defined and the requested timestamp is standard time,
2266 the tz library's localtime and mktime functions now set the extern
2267 variable timezone to a value appropriate for that timestamp; and
2268 similarly for ALTZONE, daylight saving time, and the altzone variable.
2269 This change is a companion to the tzname change in 2014h, and is
2270 designed to make timezone and altzone more compatible with tzname.
2272 The tz library's functions now set errno to EOVERFLOW if they fail
2273 because the result cannot be represented. ctime and ctime_r now
2274 return NULL and set errno when a timestamp is out of range, rather
2275 than having undefined behavior.
2277 Some bugs associated with the new 2014g functions have been fixed.
2278 This includes a bug that largely incapacitated the new functions
2279 time2posix_z and posix2time_z. (Thanks to Christos Zoulas.)
2280 It also includes some uses of uninitialized variables after tzalloc.
2281 The new code uses the standard type 'ssize_t', which the Makefile
2282 now gives porting advice about.
2284 Changes affecting commentary
2286 Updated URLs for NRC Canada (thanks to Matt Johnson and Brian Inglis).
2289 Release 2014h - 2014-09-25 18:59:03 -0700
2291 Changes affecting past timestamps
2293 America/Jamaica's 1974 spring-forward transition was Jan. 6, not Apr. 28.
2295 Shanks says Asia/Novokuznetsk switched from LMT (not "NMT") on 1924-05-01,
2296 not 1920-01-06. The old entry was based on a misinterpretation of Shanks.
2298 Some more zones have been turned into links, when they differed
2299 from existing zones only for older timestamps. As usual,
2300 these changes affect UT offsets in pre-1970 timestamps only.
2301 Their old contents have been moved to the 'backzone' file.
2302 The affected zones are: Africa/Blantyre, Africa/Bujumbura,
2303 Africa/Gaborone, Africa/Harare, Africa/Kigali, Africa/Lubumbashi,
2304 Africa/Lusaka, Africa/Maseru, and Africa/Mbabane.
2306 Changes affecting code
2308 zdump -V and -v now output gmtoff= values on all platforms,
2309 not merely on platforms defining TM_GMTOFF.
2311 The tz library's localtime and mktime functions now set tzname to a value
2312 appropriate for the requested timestamp, and zdump now uses this
2313 on platforms not defining TM_ZONE, fixing a 2014g regression.
2314 (Thanks to Tim Parenti for reporting the problem.)
2316 The tz library no longer sets tzname if localtime or mktime fails.
2318 zdump -c no longer mishandles transitions near year boundaries.
2319 (Thanks to Tim Parenti for reporting the problem.)
2321 An access to uninitialized data has been fixed.
2322 (Thanks to Jörg Richter for reporting the problem.)
2324 When THREAD_SAFE is defined, the code ports to the C11 memory model.
2325 A memory leak has been fixed if ALL_STATE and THREAD_SAFE are defined
2326 and two threads race to initialize data used by gmtime-like functions.
2327 (Thanks to Andy Heninger for reporting the problems.)
2329 Changes affecting build procedure
2331 'make check' now checks better for properly-sorted data.
2333 Changes affecting documentation and commentary
2335 zdump's gmtoff=N output is now documented, and its isdst=D output
2336 is now documented to possibly output D values other than 0 or 1.
2338 zdump -c's treatment of years is now documented to use the
2339 Gregorian calendar and Universal Time without leap seconds,
2340 and its behavior at cutoff boundaries is now documented better.
2341 (Thanks to Arthur David Olson and Tim Parenti for reporting the problems.)
2343 Programs are now documented to use the proleptic Gregorian calendar.
2344 (Thanks to Alan Barrett for the suggestion.)
2346 Fractional-second GMT offsets have been documented for civil time
2347 in 19th-century Chennai, Jakarta, and New York.
2350 Release 2014g - 2014-08-28 12:31:23 -0700
2352 Changes affecting future timestamps
2354 Turks & Caicos is switching from US eastern time to UT -04
2355 year-round, modeled as a switch on 2014-11-02 at 02:00.
2356 [As noted in 2014j, this switch was later delayed.]
2358 Changes affecting past timestamps
2360 Time in Russia or the USSR before 1926 or so has been corrected by
2361 a few seconds in the following zones: Asia/Irkutsk,
2362 Asia/Krasnoyarsk, Asia/Omsk, Asia/Samarkand, Asia/Tbilisi,
2363 Asia/Vladivostok, Asia/Yakutsk, Europe/Riga, Europe/Samara. For
2364 Asia/Yekaterinburg the correction is a few minutes. (Thanks to
2365 Vladimir Karpinsky.)
2367 The Portuguese decree of 1911-05-26 took effect on 1912-01-01.
2368 This affects 1911 timestamps in Africa/Bissau, Africa/Luanda,
2369 Atlantic/Azores, and Atlantic/Madeira. Also, Lisbon's pre-1912
2370 GMT offset was -0:36:45 (rounded from -0:36:44.68), not -0:36:32.
2371 (Thanks to Stephen Colebourne for pointing to the decree.)
2373 Asia/Dhaka ended DST on 2009-12-31 at 24:00, not 23:59.
2375 A new file 'backzone' contains data which may appeal to
2376 connoisseurs of old timestamps, although it is out of scope for
2377 the tz database, is often poorly sourced, and contains some data
2378 that is known to be incorrect. The new file is not recommended
2379 for ordinary use and its entries are not installed by default.
2380 (Thanks to Lester Caine for the high-quality Jersey, Guernsey, and
2381 Isle of Man entries.)
2383 Some more zones have been turned into links, when they differed
2384 from existing zones only for older timestamps. As usual,
2385 these changes affect UT offsets in pre-1970 timestamps only.
2386 Their old contents have been moved to the 'backzone' file.
2387 The affected zones are: Africa/Bangui, Africa/Brazzaville,
2388 Africa/Douala, Africa/Kinshasa, Africa/Libreville, Africa/Luanda,
2389 Africa/Malabo, Africa/Niamey, and Africa/Porto-Novo.
2391 Changes affecting code
2393 Unless NETBSD_INSPIRED is defined to 0, the tz library now
2394 supplies functions for creating and using objects that represent
2395 timezones. The new functions are tzalloc, tzfree, localtime_rz,
2396 mktime_z, and (if STD_INSPIRED is also defined) posix2time_z and
2397 time2posix_z. They are intended for performance: for example,
2398 localtime_rz (unlike localtime_r) is trivially thread-safe without
2399 locking. (Thanks to Christos Zoulas for proposing NetBSD-inspired
2400 functions, and to Alan Barrett and Jonathan Lennox for helping to
2403 zdump now builds with the tz library unless USE_LTZ is defined to 0,
2404 This lets zdump use tz features even if the system library lacks them.
2405 To build zdump with the system library, use 'make CFLAGS=-DUSE_LTZ=0
2406 TZDOBJS=zdump.o CHECK_TIME_T_ALTERNATIVES='.
2408 zdump now uses localtime_rz if available, as it's significantly faster,
2409 and it can help zdump better diagnose invalid timezone names.
2410 Define HAVE_LOCALTIME_RZ to 0 to suppress this. HAVE_LOCALTIME_RZ
2411 defaults to 1 if NETBSD_INSPIRED && USE_LTZ. When localtime_rz is
2412 not available, zdump now uses localtime_r and tzset if available,
2413 as this is a bit cleaner and faster than plain localtime. Compile
2414 with -DHAVE_LOCALTIME_R=0 and/or -DHAVE_TZSET=0 if your system
2415 lacks these two functions.
2417 If THREAD_SAFE is defined to 1, the tz library is now thread-safe.
2418 Although not needed for tz's own applications, which are single-threaded,
2419 this supports POSIX better if the tz library is used in multithreaded apps.
2421 Some crashes have been fixed when zdump or the tz library is given
2422 invalid or outlandish input.
2424 The tz library no longer mishandles leap seconds on platforms with
2425 unsigned time_t in timezones that lack ordinary transitions after 1970.
2427 The tz code now attempts to infer TM_GMTOFF and TM_ZONE if not
2428 already defined, to make it easier to configure on common platforms.
2429 Define NO_TM_GMTOFF and NO_TM_ZONE to suppress this.
2431 Unless the new macro UNINIT_TRAP is defined to 1, the tz code now
2432 assumes that reading uninitialized memory yields garbage values
2433 but does not cause other problems such as traps.
2435 If TM_GMTOFF is defined and UNINIT_TRAP is 0, mktime is now
2436 more likely to guess right for ambiguous timestamps near
2437 transitions where tm_isdst does not change.
2439 If HAVE_STRFTIME_L is defined to 1, the tz library now defines
2440 strftime_l for compatibility with recent versions of POSIX.
2441 Only the C locale is supported, though. HAVE_STRFTIME_L defaults
2442 to 1 on recent POSIX versions, and to 0 otherwise.
2444 tzselect -c now uses a hybrid distance measure that works better
2445 in Africa. (Thanks to Alan Barrett for noting the problem.)
2447 The C source code now ports to NetBSD when GCC_DEBUG_FLAGS is used,
2448 or when time_tz is defined.
2450 When HAVE_UTMPX_H is set the 'date' command now builds on systems
2451 whose <utmpx.h> file does not define WTMPX_FILE, and when setting
2452 the date it updates the wtmpx file if _PATH_WTMPX is defined.
2453 This affects GNU/Linux and similar systems.
2455 For easier maintenance later, some C code has been simplified,
2456 some lint has been removed, and the code has been tweaked so that
2457 plain 'make' is more likely to work.
2459 The C type 'bool' is now used for boolean values, instead of 'int'.
2461 The long-obsolete LOCALE_HOME code has been removed.
2463 The long-obsolete 'gtime' function has been removed.
2465 Changes affecting build procedure
2467 'zdump' no longer links in ialloc.o, as it's not needed.
2469 'make check_time_t_alternatives' no longer assumes GNU diff.
2471 Changes affecting distribution tarballs
2473 The files checktab.awk and zoneinfo2tdf.pl are now distributed in
2474 the tzdata tarball instead of the tzcode tarball, since they help
2475 maintain the data. The NEWS and Theory files are now also
2476 distributed in the tzdata tarball, as they're relevant for data.
2477 (Thanks to Alan Barrett for pointing this out.) Also, the
2478 leapseconds.awk file is no longer distributed in the tzcode
2479 tarball, since it belongs in the tzdata tarball (where 2014f
2480 inadvertently also distributed it).
2482 Changes affecting documentation and commentary
2484 A new file CONTRIBUTING is distributed. (Thanks to Tim Parenti for
2485 suggesting a CONTRIBUTING file, and to Tony Finch and Walter Harms
2488 The man pages have been updated to use function prototypes,
2489 to document thread-safe variants like localtime_r, and to document
2490 the NetBSD-inspired functions tzalloc, tzfree, localtime_rz, and
2493 The fields in Link lines have been renamed to be more descriptive
2494 and more like the parameters of 'ln'. LINK-FROM has become TARGET,
2495 and LINK-TO has become LINK-NAME.
2497 tz-link.htm mentions the IETF's tzdist working group; Windows
2498 Runtime etc. (thanks to Matt Johnson); and HP-UX's tztab.
2500 Some broken URLs have been fixed in the commentary. (Thanks to
2503 Commentary about Philippines DST has been updated, and commentary
2504 on pre-1970 time in India has been added.
2507 Release 2014f - 2014-08-05 17:42:36 -0700
2509 Changes affecting future timestamps
2511 Russia will subtract an hour from most of its time zones on 2014-10-26
2512 at 02:00 local time. (Thanks to Alexander Krivenyshev.)
2513 There are a few exceptions: Magadan Oblast (Asia/Magadan) and Zabaykalsky
2514 Krai are subtracting two hours; conversely, Chukotka Autonomous Okrug
2515 (Asia/Anadyr), Kamchatka Krai (Asia/Kamchatka), Kemerovo Oblast
2516 (Asia/Novokuznetsk), and the Samara Oblast and the Udmurt Republic
2517 (Europe/Samara) are not changing their clocks. The changed zones are
2518 Europe/Kaliningrad, Europe/Moscow, Europe/Simferopol, Europe/Volgograd,
2519 Asia/Yekaterinburg, Asia/Omsk, Asia/Novosibirsk, Asia/Krasnoyarsk,
2520 Asia/Irkutsk, Asia/Yakutsk, Asia/Vladivostok, Asia/Khandyga,
2521 Asia/Sakhalin, and Asia/Ust-Nera; Asia/Magadan will have two hours
2522 subtracted; and Asia/Novokuznetsk's time zone abbreviation is affected,
2523 but not its UTC offset. Two zones are added: Asia/Chita (split
2524 from Asia/Yakutsk, and also with two hours subtracted) and
2525 Asia/Srednekolymsk (split from Asia/Magadan, but with only one hour
2526 subtracted). (Thanks to Tim Parenti for much of the above.)
2528 Changes affecting time zone abbreviations
2530 Australian eastern time zone abbreviations are now AEST/AEDT not EST,
2531 and similarly for the other Australian zones. That is, for eastern
2532 standard and daylight saving time the abbreviations are AEST and AEDT
2533 instead of the former EST for both; similarly, ACST/ACDT, ACWST/ACWDT,
2534 and AWST/AWDT are now used instead of the former CST, CWST, and WST.
2535 This change does not affect UT offsets, only time zone abbreviations.
2536 (Thanks to Rich Tibbett and many others.)
2538 Asia/Novokuznetsk shifts from NOVT to KRAT (remaining on UT +07)
2539 effective 2014-10-26 at 02:00 local time.
2541 The time zone abbreviation for Xinjiang Time (observed in Ürümqi)
2542 has been changed from URUT to XJT. (Thanks to Luther Ma.)
2544 Prefer MSK/MSD for Moscow time in Russia, even in other cities.
2545 Similarly, prefer EET/EEST for eastern European time in Russia.
2547 Change time zone abbreviations in (western) Samoa to use "ST" and
2548 "DT" suffixes, as this is more likely to match common practice.
2549 Prefix "W" to (western) Samoa time when its standard-time offset
2550 disagrees with that of American Samoa.
2552 America/Metlakatla now uses PST, not MeST, to abbreviate its time zone.
2554 Time zone abbreviations have been updated for Japan's two time
2555 zones used 1896-1937. JWST now stands for Western Standard
2556 Time, and JCST for Central Standard Time (formerly this was CJT).
2557 These abbreviations are now used for time in Korea, Taiwan,
2558 and Sakhalin while controlled by Japan.
2560 Changes affecting past timestamps
2562 China's five zones have been simplified to two, since the post-1970
2563 differences in the other three seem to have been imaginary. The
2564 zones Asia/Harbin, Asia/Chongqing, and Asia/Kashgar have been
2565 removed; backwards-compatibility links still work, albeit with
2566 different behaviors for timestamps before May 1980. Asia/Urumqi's
2567 1980 transition to UT +08 has been removed, so that it is now at
2568 +06 and not +08. (Thanks to Luther Ma and to Alois Treindl;
2569 Treindl sent helpful translations of two papers by Guo Qingsheng.)
2571 Some zones have been turned into links, when they differed from existing
2572 zones only for older UT offsets where data entries were likely invented.
2573 These changes affect UT offsets in pre-1970 timestamps only. This is
2574 similar to the change in release 2013e, except this time for western
2575 Africa. The affected zones are: Africa/Bamako, Africa/Banjul,
2576 Africa/Conakry, Africa/Dakar, Africa/Freetown, Africa/Lome,
2577 Africa/Nouakchott, Africa/Ouagadougou, Africa/Sao_Tome, and
2578 Atlantic/St_Helena. This also affects the backwards-compatibility
2579 link Africa/Timbuktu. (Thanks to Alan Barrett, Stephen Colebourne,
2580 Tim Parenti, and David Patte for reporting problems in earlier
2581 versions of this change.)
2583 Asia/Shanghai's pre-standard-time UT offset has been changed from
2584 8:05:57 to 8:05:43, the location of Xujiahui Observatory. Its
2585 transition to standard time has been changed from 1928 to 1901.
2587 Asia/Taipei switched to JWST on 1896-01-01, then to JST on 1937-10-01,
2588 then to CST on 1945-09-21 at 01:00, and did not observe DST in 1945.
2589 In 1946 it observed DST from 05-15 through 09-30; in 1947
2590 from 04-15 through 10-31; and in 1979 from 07-01 through 09-30.
2591 (Thanks to Yu-Cheng Chuang.)
2593 Asia/Riyadh's transition to standard time is now 1947-03-14, not 1950.
2595 Europe/Helsinki's 1942 fall-back transition was 10-04 at 01:00, not
2596 10-03 at 00:00. (Thanks to Konstantin Hyppönen.)
2598 Pacific/Pago_Pago has been changed from UT -11:30 to -11 for the
2599 period from 1911 to 1950.
2601 Pacific/Chatham has been changed to New Zealand standard time plus
2602 45 minutes for the period before 1957, reflecting a 1956 remark in
2603 the New Zealand parliament.
2605 Europe/Budapest has several pre-1946 corrections: in 1918 the transition
2606 out of DST was on 09-16, not 09-29; in 1919 it was on 11-24, not 09-15; in
2607 1945 it was on 11-01, not 11-03; in 1941 the transition to DST was 04-08
2608 not 04-06 at 02:00; and there was no DST in 1920.
2610 Africa/Accra is now assumed to have observed DST from 1920 through 1935.
2612 Time in Russia before 1927 or so has been corrected by a few seconds in
2613 the following zones: Europe/Moscow, Asia/Irkutsk, Asia/Tbilisi,
2614 Asia/Tashkent, Asia/Vladivostok, Asia/Yekaterinburg, Europe/Helsinki, and
2615 Europe/Riga. Also, Moscow's location has been changed to its Kilometer 0
2616 point. (Thanks to Vladimir Karpinsky for the Moscow changes.)
2618 Changes affecting data format
2620 A new file 'zone1970.tab' supersedes 'zone.tab' in the installed data.
2621 The new file's extended format allows multiple country codes per zone.
2622 The older file is still installed but is deprecated; its format is
2623 not changing and it will still be distributed for a while, but new
2624 applications should use the new file.
2626 The new file format simplifies maintenance of obscure locations.
2627 To test this, it adds coverage for the Crozet Islands and the
2628 Scattered Islands. (Thanks to Tobias Conradi and Antoine Leca.)
2630 The file 'iso3166.tab' is planned to switch from ASCII to UTF-8.
2631 It is still ASCII now, but commentary about the switch has been added.
2632 The new file 'zone1970.tab' already uses UTF-8.
2634 Changes affecting code
2636 'localtime', 'mktime', etc. now use much less stack space if ALL_STATE
2637 is defined. (Thanks to Elliott Hughes for reporting the problem.)
2639 'zic' no longer mishandles input when ignoring case in locales that
2640 are not compatible with English, e.g., unibyte Turkish locales when
2641 compiled with HAVE_GETTEXT.
2643 Error diagnostics of 'zic' and 'yearistype' have been reworded so that
2644 they no longer use ASCII '-' as if it were a dash.
2646 'zic' now rejects output file names that contain '.' or '..' components.
2647 (Thanks to Tim Parenti for reporting the problem.)
2649 'zic -v' now warns about output file names that do not follow
2650 POSIX rules, or that contain a digit or '.'. (Thanks to Arthur
2651 David Olson for starting the ball rolling on this.)
2653 Some lint has been removed when using GCC_DEBUG_FLAGS with GCC 4.9.0.
2655 Changes affecting build procedure
2657 'zic' no longer links in localtime.o and asctime.o, as they're not needed.
2658 (Thanks to John Cochran.)
2660 Changes affecting documentation and commentary
2662 The 'Theory' file documents legacy names, the longstanding
2663 exceptions to the POSIX-inspired file name rules.
2665 The 'zic' documentation clarifies the role of time types when
2666 interpreting dates. (Thanks to Arthur David Olson.)
2668 Documentation and commentary now prefer UTF-8 to US-ASCII,
2669 allowing the use of proper accents in foreign words and names.
2670 Code and data have not changed because of this. (Thanks to
2671 Garrett Wollman, Ian Abbott, and Guy Harris for helping to debug
2674 Non-HTML documentation and commentary now use plain-text URLs instead of
2675 HTML insertions, and are more consistent about bracketing URLs when they
2676 are not already surrounded by white space. (Thanks to suggestions by
2679 There is new commentary about Xujiahui Observatory, the five time-zone
2680 project in China from 1918 to 1949, timekeeping in Japanese-occupied
2681 Shanghai, and Tibet Time in the 1950s. The sharp-eyed can spot the
2682 warlord Jin Shuren in the data.
2684 Commentary about the coverage of each Russian zone has been standardized.
2685 (Thanks to Tim Parenti.)
2687 There is new commentary about contemporary timekeeping in Ethiopia.
2689 Obsolete comments about a 2007 proposal for DST in Kuwait has been removed.
2691 There is new commentary about time in Poland in 1919.
2693 Proper credit has been given to DST inventor George Vernon Hudson.
2695 Commentary about time in Metlakatla, AK and Resolute, NU has been
2696 improved, with a new source for the former.
2698 In zone.tab, Pacific/Easter no longer mentions Salas y Gómez, as it
2701 Commentary about permanent Antarctic bases has been updated.
2703 Several typos have been corrected. (Thanks to Tim Parenti for
2704 contributing some of these fixes.)
2706 tz-link.htm now mentions the JavaScript libraries Moment Timezone,
2707 TimezoneJS.Date, Walltime-js, and Timezone. (Thanks to a heads-up
2708 from Matt Johnson.) Also, it mentions the Go 'latlong' package.
2709 (Thanks to a heads-up from Dirkjan Ochtman.)
2711 The files usno1988, usno1989, usno1989a, usno1995, usno1997, and usno1998
2712 have been removed. These obsolescent US Naval Observatory entries were no
2713 longer helpful for maintenance. (Thanks to Tim Parenti for the suggestion.)
2716 Release 2014e - 2014-06-12 21:53:52 -0700
2718 Changes affecting near-future timestamps
2720 Egypt's 2014 Ramadan-based transitions are June 26 and July 31 at 24:00.
2721 (Thanks to Imed Chihi.) Guess that from 2015 on Egypt will temporarily
2722 switch to standard time at 24:00 the last Thursday before Ramadan, and
2723 back to DST at 00:00 the first Friday after Ramadan.
2725 Similarly, Morocco's are June 28 at 03:00 and August 2 at 02:00. (Thanks
2726 to Milamber Space Network.) Guess that from 2015 on Morocco will
2727 temporarily switch to standard time at 03:00 the last Saturday before
2728 Ramadan, and back to DST at 02:00 the first Saturday after Ramadan.
2730 Changes affecting past timestamps
2732 The abbreviation "MSM" (Moscow Midsummer Time) is now used instead of
2733 "MSD" for Moscow's double daylight time in summer 1921. Also, a typo
2734 "VLASST" has been repaired to be "VLAST" for Vladivostok summer time
2735 in 1991. (Thanks to Hank W. for reporting the problems.)
2737 Changes affecting commentary
2739 tz-link.htm now cites RFC 7265 for jCal, mentions PTP and the
2740 draft CalDAV extension, updates URLs for TSP, TZInfo, IATA, and
2741 removes stale pointers to World Time Explorer and WORLDTIME.
2744 Release 2014d - 2014-05-27 21:34:40 -0700
2746 Changes affecting code
2748 zic no longer generates files containing timestamps before the Big Bang.
2749 This works around GNOME glib bug 878
2750 <https://gitlab.gnome.org/GNOME/glib/issues/878>
2751 (Thanks to Leonardo Chiquitto for reporting the bug, and to
2752 Arthur David Olson and James Cloos for suggesting improvements to the fix.)
2754 Changes affecting documentation
2756 tz-link.htm now mentions GNOME.
2759 Release 2014c - 2014-05-13 07:44:13 -0700
2761 Changes affecting near-future timestamps
2763 Egypt observes DST starting 2014-05-15 at 24:00.
2764 (Thanks to Ahmad El-Dardiry and Gunther Vermier.)
2765 Details have not been announced, except that DST will not be observed
2766 during Ramadan. Guess that DST will stop during the same Ramadan dates as
2767 Morocco, and that Egypt's future spring and fall transitions will be the
2768 same as 2010 when it last observed DST, namely April's last Friday at
2769 00:00 to September's last Thursday at 23:00 standard time. Also, guess
2770 that Ramadan transitions will be at 00:00 standard time.
2772 Changes affecting code
2774 zic now generates transitions for minimum time values, eliminating guesswork
2775 when handling low-valued timestamps. (Thanks to Arthur David Olson.)
2777 Port to Cygwin sans glibc. (Thanks to Arthur David Olson.)
2779 Changes affecting commentary and documentation
2781 Remove now-confusing comment about Jordan. (Thanks to Oleksii Nochovnyi.)
2784 Release 2014b - 2014-03-24 21:28:50 -0700
2786 Changes affecting near-future timestamps
2788 Crimea switches to Moscow time on 2014-03-30 at 02:00 local time.
2789 (Thanks to Alexander Krivenyshev.) Move its zone.tab entry from UA to RU.
2791 New entry for Troll station, Antarctica. (Thanks to Paul-Inge Flakstad and
2792 Bengt-Inge Larsson.) This is currently an approximation; a better version
2793 will require the zic and localtime fixes mentioned below, and the plan is
2794 to wait for a while until at least the zic fixes propagate.
2796 Changes affecting code
2798 'zic' and 'localtime' no longer reject locations needing four transitions
2799 per year for the foreseeable future. (Thanks to Andrew Main (Zefram).)
2800 Also, 'zic' avoids some unlikely failures due to integer overflow.
2802 Changes affecting build procedure
2804 'make check' now detects Rule lines defined but never used.
2805 The NZAQ rules, an instance of this problem, have been removed.
2807 Changes affecting commentary and documentation
2809 Fix Tuesday/Thursday typo in description of time in Israel.
2810 (Thanks to Bert Katz via Pavel Kharitonov and Mike Frysinger.)
2812 Microsoft Windows 8.1 doesn't support tz database names. (Thanks
2813 to Donald MacQueen.) Instead, the Microsoft Windows Store app
2814 library supports them.
2816 Add comments about Johnston Island time in the 1960s.
2817 (Thanks to Lyle McElhaney.)
2819 Morocco's 2014 DST start will be as predicted.
2820 (Thanks to Sebastien Willemijns.)
2823 Release 2014a - 2014-03-07 23:30:29 -0800
2825 Changes affecting near-future timestamps
2827 Turkey begins DST on 2014-03-31, not 03-30. (Thanks to Faruk Pasin for
2828 the heads-up, and to Tim Parenti for simplifying the update.)
2830 Changes affecting past timestamps
2832 Fiji ended DST on 2014-01-19 at 02:00, not the previously-scheduled 03:00.
2833 (Thanks to Steffen Thorsen.)
2835 Ukraine switched from Moscow to Eastern European time on 1990-07-01
2836 (not 1992-01-01), and observed DST during the entire next winter.
2837 (Thanks to Vladimir in Moscow via Alois Treindl.)
2839 In 1988 Israel observed DST from 04-10 to 09-04, not 04-09 to 09-03.
2840 (Thanks to Avigdor Finkelstein.)
2842 Changes affecting code
2844 A uninitialized-storage bug in 'localtime' has been fixed.
2845 (Thanks to Logan Chien.)
2847 Changes affecting the build procedure
2849 The settings for 'make check_web' now default to Ubuntu 13.10.
2851 Changes affecting commentary and documentation
2853 The boundary of the US Pacific time zone is given more accurately.
2854 (Thanks to Alan Mintz.)
2856 Chile's 2014 DST will be as predicted. (Thanks to José Miguel Garrido.)
2858 Paraguay's 2014 DST will be as predicted. (Thanks to Carlos Raúl Perasso.)
2860 Better descriptions of countries with same time zone history as
2861 Trinidad and Tobago since 1970. (Thanks to Alan Barrett for suggestion.)
2863 Several changes affect tz-link.htm, the main web page.
2865 Mention Time.is (thanks to Even Scharning) and WX-now (thanks to
2868 Mention xCal (Internet RFC 6321) and jCal.
2870 Microsoft has some support for tz database names.
2872 CLDR data formats include both XML and JSON.
2874 Mention Maggiolo's map of solar vs standard time.
2875 (Thanks to Arthur David Olson.)
2877 Mention TZ4Net. (Thanks to Matt Johnson.)
2879 Mention the timezone-olson Haskell package.
2881 Mention zeitverschiebung.net. (Thanks to Martin Jäger.)
2883 Remove moribund links to daylight-savings-time.info and to
2884 Simple Timer + Clocks.
2886 Update two links. (Thanks to Oscar van Vlijmen.)
2888 Fix some formatting glitches, e.g., remove random newlines from
2889 abbr elements' title attributes.
2892 Release 2013i - 2013-12-17 07:25:23 -0800
2894 Changes affecting near-future timestamps:
2896 Jordan switches back to standard time at 00:00 on December 20, 2013.
2897 The 2006-2011 transition schedule is planned to resume in 2014.
2898 (Thanks to Steffen Thorsen.)
2900 Changes affecting past timestamps:
2902 In 2004, Cuba began DST on March 28, not April 4.
2903 (Thanks to Steffen Thorsen.)
2905 Changes affecting code
2907 The compile-time flag NOSOLAR has been removed, as nowadays the
2908 benefit of slightly shrinking runtime table size is outweighed by the
2909 cost of disallowing potential future updates that exceed old limits.
2911 Changes affecting documentation and commentary
2913 The files solar87, solar88, and solar89 are no longer distributed.
2914 They were a negative experiment - that is, a demonstration that
2915 tz data can represent solar time only with some difficulty and error.
2916 Their presence in the distribution caused confusion, as Riyadh
2917 civil time was generally not solar time in those years.
2919 tz-link.htm now mentions Noda Time. (Thanks to Matt Johnson.)
2922 Release 2013h - 2013-10-25 15:32:32 -0700
2924 Changes affecting current and future timestamps:
2926 Libya has switched its UT offset back to +02 without DST, instead
2927 of +01 with DST. (Thanks to Even Scharning.)
2929 Western Sahara (Africa/El_Aaiun) uses Morocco's DST rules.
2930 (Thanks to Gwillim Law.)
2932 Changes affecting future timestamps:
2934 Acre and (we guess) western Amazonas will switch from UT -04 to -05
2935 on 2013-11-10. This affects America/Rio_Branco and America/Eirunepe.
2936 (Thanks to Steffen Thorsen.)
2938 Add entries for DST transitions in Morocco in the year 2038.
2939 This avoids some year-2038 glitches introduced in 2013g.
2940 (Thanks to Yoshito Umaoka for reporting the problem.)
2942 Changes affecting API
2944 The 'tzselect' command no longer requires the 'select' command,
2945 and should now work with /bin/sh on more platforms. It also works
2946 around a bug in BusyBox awk before version 1.21.0. (Thanks to
2947 Patrick 'P. J.' McDermott and Alan Barrett.)
2949 Changes affecting code
2951 Fix localtime overflow bugs with 32-bit unsigned time_t.
2953 zdump no longer assumes sscanf returns maximal values on overflow.
2955 Changes affecting the build procedure
2957 The builder can specify which programs to use, if any, instead of
2958 'ar' and 'ranlib', and libtz.a is now built locally before being
2959 installed. (Thanks to Michael Forney.)
2961 A dependency typo in the 'zdump' rule has been fixed.
2962 (Thanks to Andrew Paprocki.)
2964 The Makefile has been simplified by assuming that 'mkdir -p' and 'cp -f'
2965 work as specified by POSIX.2-1992 or later; this is portable nowadays.
2967 'make clean' no longer removes 'leapseconds', since it's
2968 host-independent and is part of the distribution.
2970 The unused makefile macros TZCSRCS, TZDSRCS, DATESRCS have been removed.
2972 Changes affecting documentation and commentary
2974 tz-link.htm now mentions TC TIMEZONE's draft time zone service protocol
2975 (thanks to Mike Douglass) and TimezoneJS.Date (thanks to Jim Fehrle).
2977 Update URLs in tz-link page. Add URLs for Microsoft Windows, since
2978 8.1 introduces tz support. Remove URLs for Tru64 and UnixWare (no
2979 longer maintained) and for old advisories. SOFA now does C.
2981 Release 2013g - 2013-09-30 21:08:26 -0700
2983 Changes affecting current and near-future timestamps
2985 Morocco now observes DST from the last Sunday in March to the last
2986 Sunday in October, not April to September respectively. (Thanks
2987 to Steffen Thorsen.)
2989 Changes affecting 'zic'
2991 'zic' now runs on platforms that lack both hard links and symlinks.
2992 (Thanks to Theo Veenker for reporting the problem, for MinGW.)
2993 Also, fix some bugs on platforms that lack hard links but have symlinks.
2995 'zic -v' again warns that Asia/Tehran has no POSIX environment variable
2996 to predict the far future, fixing a bug introduced in 2013e.
2998 Changes affecting the build procedure
3000 The 'leapseconds' file is again put into the tzdata tarball.
3001 Also, 'leapseconds.awk', so tzdata is self-contained. (Thanks to
3002 Matt Burgess and Ian Abbott.) The timestamps of these and other
3003 dependent files in tarballs are adjusted more consistently.
3005 Changes affecting documentation and commentary
3007 The README file is now part of the data tarball as well as the code.
3008 It now states that files are public domain unless otherwise specified.
3009 (Thanks to Andrew Main (Zefram) for asking for clarifications.)
3010 Its details about the 1989 release moved to a place of honor near
3014 Release 2013f - 2013-09-24 23:37:36 -0700
3016 Changes affecting near-future timestamps
3018 Tocantins will very likely not observe DST starting this spring.
3019 (Thanks to Steffen Thorsen.)
3021 Jordan will likely stay at UT +03 indefinitely, and will not fall
3024 Palestine will fall back at 00:00, not 01:00. (Thanks to Steffen Thorsen.)
3026 Changes affecting API
3028 The types of the global variables 'timezone' and 'altzone' (if present)
3029 have been changed back to 'long'. This is required for 'timezone'
3030 by POSIX, and for 'altzone' by common practice, e.g., Solaris 11.
3031 These variables were originally 'long' in the tz code, but were
3032 mistakenly changed to 'time_t' in 1987; nobody reported the
3033 incompatibility until now. The difference matters on x32, where
3034 'long' is 32 bits and 'time_t' is 64. (Thanks to Elliott Hughes.)
3036 Changes affecting the build procedure
3038 Avoid long strings in leapseconds.awk to work around a mawk bug.
3039 (Thanks to Cyril Baurand.)
3041 Changes affecting documentation and commentary
3043 New file 'NEWS' that contains release notes like this one.
3045 Paraguay's law does not specify DST transition time; 00:00 is customary.
3046 (Thanks to Waldemar Villamayor-Venialbo.)
3048 Minor capitalization fixes.
3050 Changes affecting version-control only
3052 The experimental GitHub repository now contains annotated and
3053 signed tags for recent releases, e.g., '2013e' for Release 2013e.
3054 Releases are tagged starting with 2012e; earlier releases were
3055 done differently, and tags would either not have a simple name or
3056 not exactly match what was released.
3058 'make set-timestamps' is now simpler and a bit more portable.
3061 Release 2013e - 2013-09-19 23:50:04 -0700
3063 Changes affecting near-future timestamps
3065 This year Fiji will start DST on October 27, not October 20.
3066 (Thanks to David Wheeler for the heads-up.) For now, guess that
3067 Fiji will continue to spring forward the Sunday before the fourth
3070 Changes affecting current and future time zone abbreviations
3072 Use WIB/WITA/WIT rather than WIT/CIT/EIT for alphabetic Indonesian
3073 time zone abbreviations since 1932. (Thanks to George Ziegler,
3074 Priyadi Iman Nurcahyo, Zakaria, Jason Grimes, Martin Pitt, and
3075 Benny Lin.) This affects Asia/Dili, Asia/Jakarta, Asia/Jayapura,
3076 Asia/Makassar, and Asia/Pontianak.
3078 Use ART (UT -03, standard time), rather than WARST (also -03, but
3079 daylight saving time) for San Luis, Argentina since 2009.
3081 Changes affecting Godthåb timestamps after 2037 if version mismatch
3083 Allow POSIX-like TZ strings where the transition time's hour can
3084 range from -167 through 167, instead of the POSIX-required 0
3085 through 24. E.g., TZ='FJT-12FJST,M10.3.1/146,M1.3.4/75' for the
3086 new Fiji rules. This is a more-compact way to represent
3087 far-future timestamps for America/Godthab, America/Santiago,
3088 Antarctica/Palmer, Asia/Gaza, Asia/Hebron, Asia/Jerusalem,
3089 Pacific/Easter, and Pacific/Fiji. Other zones are unaffected by
3090 this change. (Derived from a suggestion by Arthur David Olson.)
3092 Allow POSIX-like TZ strings where daylight saving time is in
3093 effect all year. E.g., TZ='WART4WARST,J1/0,J365/25' for Western
3094 Argentina Summer Time all year. This supports a more-compact way
3095 to represent the 2013d data for America/Argentina/San_Luis.
3096 Because of the change for San Luis noted above this change does not
3097 affect the current data. (Thanks to Andrew Main (Zefram) for
3098 suggestions that improved this change.)
3100 Where these two TZ changes take effect, there is a minor extension
3101 to the tz file format in that it allows new values for the
3102 embedded TZ-format string, and the tz file format version number
3103 has therefore been increased from 2 to 3 as a precaution.
3104 Version-2-based client code should continue to work as before for
3105 all timestamps before 2038. Existing version-2-based client code
3106 (tzcode, GNU/Linux, Solaris) has been tested on version-3-format
3107 files, and typically works in practice even for timestamps after
3108 2037; the only known exception is America/Godthab.
3110 Changes affecting timestamps before 1970
3112 Pacific/Johnston is now a link to Pacific/Honolulu. This corrects
3113 some errors before 1947.
3115 Some zones have been turned into links, when they differ from existing
3116 zones only in older data entries that were likely invented or that
3117 differ only in LMT or transitions from LMT. These changes affect
3118 only timestamps before 1943. The affected zones are:
3119 Africa/Juba, America/Anguilla, America/Aruba, America/Dominica,
3120 America/Grenada, America/Guadeloupe, America/Marigot,
3121 America/Montserrat, America/St_Barthelemy, America/St_Kitts,
3122 America/St_Lucia, America/St_Thomas, America/St_Vincent,
3123 America/Tortola, and Europe/Vaduz. (Thanks to Alois Treindl for
3124 confirming that the old Europe/Vaduz zone was wrong and the new
3125 link is better for WWII-era times.)
3127 Change Kingston Mean Time from -5:07:12 to -5:07:11. This affects
3128 America/Cayman, America/Jamaica and America/Grand_Turk timestamps
3131 Change the UT offset of Bern Mean Time from 0:29:44 to 0:29:46.
3132 This affects Europe/Zurich timestamps from 1853 to 1894. (Thanks
3135 Change the date of the circa-1850 Zurich transition from 1849-09-12
3136 to 1853-07-16, overriding Shanks with data from Messerli about
3137 postal and telegraph time in Switzerland.
3139 Changes affecting time zone abbreviations before 1970
3141 For Asia/Jakarta, use BMT (not JMT) for mean time from 1923 to 1932,
3142 as Jakarta was called Batavia back then.
3144 Changes affecting API
3146 The 'zic' command now outputs a dummy transition when far-future
3147 data can't be summarized using a TZ string, and uses a 402-year
3148 window rather than a 400-year window. For the current data, this
3149 affects only the Asia/Tehran file. It does not affect any of the
3150 timestamps that this file represents, so zdump outputs the same
3151 information as before. (Thanks to Andrew Main (Zefram).)
3153 The 'date' command has a new '-r' option, which lets you specify
3154 the integer time to display, a la FreeBSD.
3156 The 'tzselect' command has two new options '-c' and '-n', which lets you
3157 select a zone based on latitude and longitude.
3159 The 'zic' command's '-v' option now warns about constructs that
3160 require the new version-3 binary file format. (Thanks to Arthur
3161 David Olson for the suggestion.)
3163 Support for floating-point time_t has been removed.
3164 It was always dicey, and POSIX no longer requires it.
3165 (Thanks to Eric Blake for suggesting to the POSIX committee to
3166 remove it, and thanks to Alan Barrett, Clive D.W. Feather, Andy
3167 Heninger, Arthur David Olson, and Alois Treindl, for reporting
3168 bugs and elucidating some of the corners of the old floating-point
3171 The signatures of 'offtime', 'timeoff', and 'gtime' have been
3172 changed back to the old practice of using 'long' to represent UT
3173 offsets. This had been inadvertently and mistakenly changed to
3174 'int_fast32_t'. (Thanks to Christos Zoulas.)
3176 The code avoids undefined behavior on integer overflow in some
3177 more places, including gmtime, localtime, mktime and zdump.
3179 Changes affecting the zdump utility
3181 zdump now outputs "UT" when referring to Universal Time, not "UTC".
3182 "UTC" does not make sense for timestamps that predate the introduction
3183 of UTC, whereas "UT", a more-generic term, does. (Thanks to Steve Allen
3184 for clarifying UT vs UTC.)
3186 Data changes affecting behavior of tzselect and similar programs
3188 Country code BQ is now called the more-common name "Caribbean Netherlands"
3189 rather than the more-official "Bonaire, St Eustatius & Saba".
3191 Remove from zone.tab the names America/Montreal, America/Shiprock,
3192 and Antarctica/South_Pole, as they are equivalent to existing
3193 same-country-code zones for post-1970 timestamps. The data entries for
3194 these names are unchanged, so the names continue to work as before.
3196 Changes affecting code internals
3198 zic -c now runs way faster on 64-bit hosts when given large numbers.
3200 zic now uses vfprintf to avoid allocating and freeing some memory.
3202 tzselect now computes the list of continents from the data,
3203 rather than have it hard-coded.
3205 Minor changes pacify GCC 4.7.3 and GCC 4.8.1.
3207 Changes affecting the build procedure
3209 The 'leapseconds' file is now generated automatically from a
3210 new file 'leap-seconds.list', which is a copy of
3211 <ftp://ftp.nist.gov/pub/time/leap-seconds.list>
3212 A new source file 'leapseconds.awk' implements this.
3213 The goal is simplification of the future maintenance of 'leapseconds'.
3215 When building the 'posix' or 'right' subdirectories, if the
3216 subdirectory would be a copy of the default subdirectory, it is
3217 now made a symbolic link if that is supported. This saves about
3218 2 MB of file system space.
3220 The links America/Shiprock and Antarctica/South_Pole have been
3221 moved to the 'backward' file. This affects only nondefault builds
3222 that omit 'backward'.
3224 Changes affecting version-control only
3226 .gitignore now ignores 'date'.
3228 Changes affecting documentation and commentary
3230 Changes to the 'tzfile' man page
3232 It now mentions that the binary file format may be extended in
3233 future versions by appending data.
3235 It now refers to the 'zdump' and 'zic' man pages.
3237 Changes to the 'zic' man page
3239 It lists conditions that elicit a warning with '-v'.
3241 It says that the behavior is unspecified when duplicate names
3242 are given, or if the source of one link is the target of another.
3244 Its examples are updated to match the latest data.
3246 The definition of white space has been clarified slightly.
3247 (Thanks to Michael Deckers.)
3249 Changes to the 'Theory' file
3251 There is a new section about the accuracy of the tz database,
3252 describing the many ways that errors can creep in, and
3253 explaining why so many of the pre-1970 timestamps are wrong or
3254 misleading (thanks to Steve Allen, Lester Caine, and Garrett
3255 Wollman for discussions that contributed to this).
3257 The 'Theory' file describes LMT better (this follows a
3258 suggestion by Guy Harris).
3260 It refers to the 2013 edition of POSIX rather than the 2004 edition.
3262 It's mentioned that excluding 'backward' should not affect the
3263 other data, and it suggests at least one zone.tab name per
3264 inhabited country (thanks to Stephen Colebourne).
3266 Some longstanding restrictions on names are documented, e.g.,
3267 'America/New_York' precludes 'America/New_York/Bronx'.
3269 It gives more reasons for the 1970 cutoff.
3271 It now mentions which time_t variants are supported, such as
3272 signed integer time_t. (Thanks to Paul Goyette for reporting
3273 typos in an experimental version of this change.)
3275 (Thanks to Philip Newton for correcting typos in these changes.)
3277 Documentation and commentary is more careful to distinguish UT in
3278 general from UTC in particular. (Thanks to Steve Allen.)
3280 Add a better source for the Zurich 1894 transition.
3281 (Thanks to Pierre-Yves Berger.)
3283 Update shapefile citations in tz-link.htm. (Thanks to Guy Harris.)
3286 Release 2013d - 2013-07-05 07:38:01 -0700
3288 Changes affecting future timestamps:
3290 Morocco's midsummer transitions this year are July 7 and August 10,
3291 not July 9 and August 8. (Thanks to Andrew Paprocki.)
3293 Israel now falls back on the last Sunday of October.
3294 (Thanks to Ephraim Silverberg.)
3296 Changes affecting past timestamps:
3298 Specify Jerusalem's location more precisely; this changes the pre-1880
3301 Changing affecting metadata only:
3303 Fix typos in the entries for country codes BQ and SX.
3305 Changes affecting code:
3307 Rework the code to fix a bug with handling Australia/Macquarie on
3308 32-bit hosts (thanks to Arthur David Olson).
3310 Port to platforms like NetBSD, where time_t can be wider than long.
3312 Add support for testing time_t types other than the system's.
3313 Run 'make check_time_t_alternatives' to try this out.
3314 Currently, the tests fail for unsigned time_t;
3315 this should get fixed at some point.
3317 Changes affecting documentation and commentary:
3319 Deemphasize the significance of national borders.
3321 Update the zdump man page.
3323 Remove obsolete NOID comment (thanks to Denis Excoffier).
3325 Update several URLs and comments in the web pages.
3327 Spelling fixes (thanks to Kevin Lyda and Jonathan Leffler).
3329 Update URL for CLDR Zone->Tzid table (thanks to Yoshito Umaoka).
3332 Release 2013c - 2013-04-19 16:17:40 -0700
3334 Changes affecting current and future timestamps:
3336 Palestine observed DST starting March 29, 2013. (Thanks to
3337 Steffen Thorsen.) From 2013 on, Gaza and Hebron both observe DST,
3338 with the predicted rules being the last Thursday in March at 24:00
3339 to the first Friday on or after September 21 at 01:00.
3341 Assume that the recent change to Paraguay's DST rules is permanent,
3342 by moving the end of DST to the 4th Sunday in March every year.
3343 (Thanks to Carlos Raúl Perasso.)
3345 Changes affecting past timestamps:
3347 Fix some historical data for Palestine to agree with that of
3348 timeanddate.com, as follows:
3350 The spring 2008 change in Gaza and Hebron was on 00:00 Mar 28, not
3353 The fall 2009 change in Gaza and Hebron on Sep 4 was at 01:00, not
3356 The spring 2010 change in Hebron was 00:00 Mar 26, not 00:01 Mar 27.
3358 The spring 2011 change in Gaza was 00:01 Apr 1, not 12:01 Apr 2.
3360 The spring 2011 change in Hebron on Apr 1 was at 00:01, not 12:01.
3362 The fall 2011 change in Hebron on Sep 30 was at 00:00, not 03:00.
3364 Fix times of habitation for Macquarie to agree with the Tasmania
3365 Parks & Wildlife Service history, which indicates that permanent
3366 habitation was 1899-1919 and 1948 on.
3368 Changing affecting metadata only:
3370 Macquarie Island is politically part of Australia, not Antarctica.
3371 (Thanks to Tobias Conradi.)
3373 Sort Macquarie more-consistently with other parts of Australia.
3374 (Thanks to Tim Parenti.)
3377 Release 2013b - 2013-03-10 22:33:40 -0700
3379 Changes affecting current and future timestamps:
3381 Haiti uses US daylight-saving rules this year, and presumably future years.
3382 This changes timestamps starting today. (Thanks to Steffen Thorsen.)
3384 Paraguay will end DST on March 24 this year.
3385 (Thanks to Steffen Thorsen.) For now, assume it's just this year.
3387 Morocco does not observe DST during Ramadan;
3388 try to predict Ramadan in Morocco as best we can.
3389 (Thanks to Erik Homoet for the heads-up.)
3391 Changes affecting commentary:
3393 Update URLs in tz-link page. Add URLs for webOS, BB10, iOS.
3394 Update URL for Solaris. Mention Internet RFC 6557.
3395 Update Internet RFCs 2445->5545, 2822->5322.
3396 Switch from FTP to HTTP for Internet RFCs.
3399 Release 2013a - 2013-02-27 09:20:35 -0800
3401 Change affecting binary data format:
3403 The zone offset at the end of version-2-format zone files is now
3404 allowed to be 24:00, as per POSIX.1-2008. (Thanks to Arthur David Olson.)
3406 Changes affecting current and future timestamps:
3408 Chile's 2013 rules, and we guess rules for 2014 and later, will be
3409 the same as 2012, namely Apr Sun>=23 03:00 UTC to Sep Sun>=2 04:00 UTC.
3410 (Thanks to Steffen Thorsen and Robert Elz.)
3412 New Zones Asia/Khandyga, Asia/Ust-Nera, Europe/Busingen.
3413 (Thanks to Tobias Conradi and Arthur David Olson.)
3415 Many changes affect historical timestamps before 1940.
3416 These were deduced from: Milne J. Civil time. Geogr J. 1899
3417 Feb;13(2):173-94 <https://www.jstor.org/stable/1774359>.
3419 Changes affecting the code:
3421 Fix zic bug that mishandled Egypt's 2010 changes (this also affected
3422 the data). (Thanks to Arthur David Olson.)
3424 Fix localtime bug when time_t is unsigned and data files were generated
3425 by a signed time_t system. (Thanks to Doug Bailey for reporting and
3426 to Arthur David Olson for fixing.)
3428 Allow the email address for bug reports to be set by the packager.
3429 The default is tz@iana.org, as before. (Thanks to Joseph S. Myers.)
3431 Update HTML checking to be compatible with Ubuntu 12.10.
3433 Check that files are a safe subset of ASCII. At some point we may
3434 relax this requirement to a safe subset of UTF-8. Without the
3435 check, some non-UTF-8 encodings were leaking into the distribution.
3439 Restore a comment about copyright notices that was inadvertently deleted.
3440 (Thanks to Arthur David Olson.)
3442 Improve the commentary about which districts observe what times
3443 in Russia. (Thanks to Oscar van Vlijmen and Arthur David Olson.)
3445 Add web page links to tz.js.
3447 Add "Run by the Monkeys" to tz-art. (Thanks to Arthur David Olson.)
3450 Release 2012j - 2012-11-12 18:34:49 -0800
3452 Libya moved to CET this weekend, but with DST planned next year.
3453 (Thanks to Even Scharning, Steffen Thorsen, and Tim Parenti.)
3455 Signatures now have the extension .asc, not .sign, as that's more
3456 standard. (Thanks to Phil Pennock.)
3458 The output of 'zdump --version', and of 'zic --version', now
3459 uses a format that is more typical for --version.
3460 (Thanks to Joseph S. Myers.)
3462 The output of 'tzselect --help', 'zdump --help', and 'zic --help'
3463 now uses tz@iana.org rather than the old elsie address.
3465 zic -v now complains about abbreviations that are less than 3
3466 or more than 6 characters, as per Posix. Formerly, it checked
3467 for abbreviations that were more than 3.
3469 'make public' no longer puts its temporary directory under /tmp,
3470 and uses the just-built zic rather than the system zic.
3472 Various fixes to documentation and commentary.
3475 Release 2012i - 2012-11-03 12:57:09 -0700
3477 Cuba switches from DST tomorrow at 01:00. (Thanks to Steffen Thorsen.)
3479 Linker flags can now be specified via LDFLAGS.
3480 AWK now defaults to 'awk', not 'nawk'.
3481 The shell in tzselect now defaults to /bin/bash, but this can
3482 be overridden by specifying KSHELL.
3483 The main web page now mentions the unofficial GitHub repository.
3484 (Thanks to Mike Frysinger.)
3486 Tarball signatures can now be built by running 'make signatures'.
3487 There are also new makefile rules 'tarballs', 'check_public', and
3488 separate makefile rules for each tarball and signature file.
3489 A few makefile rules are now more portable to strict POSIX.
3491 The main web page now lists the canonical IANA URL.
3494 Release 2012h - 2012-10-26 22:49:10 -0700
3496 Bahia no longer has DST. (Thanks to Kelley Cook.)
3498 Tocantins has DST. (Thanks to Rodrigo Severo.)
3500 Israel has new DST rules next year. (Thanks to Ephraim Silverberg.)
3502 Jordan stays on DST this winter. (Thanks to Steffen Thorsen.)
3506 More C modernization, except that at Arthur David Olson's suggestion
3507 the instances of 'register' were kept.
3510 Release 2012g - 2012-10-17 20:59:45 -0700
3512 Samoa fall 2012 and later. (Thanks to Nicholas Pereira and Robert Elz.)
3514 Palestine fall 2012. (Thanks to Steffen Thorsen.)
3518 To attack the version-number problem, this release ships the file
3519 'Makefile' (which contains the release number) in both the tzcode and
3520 the tzdata tarballs. The two Makefiles are identical, and should be
3521 identical in any matching pair of tarballs, so it shouldn't matter
3522 which order you extract the tarballs. Perhaps we can come up with a
3523 better version-number scheme at some point; this scheme does have the
3524 virtue of not adding more files.
3527 Release 2012f - 2012-09-12 23:17:03 -0700
3529 * australasia (Pacific/Fiji): Fiji DST is October 21 through January
3530 20 this year. (Thanks to Steffen Thorsen.)
3533 Release 2012e - 2012-08-02 20:44:55 -0700
3535 * australasia (Pacific/Fakaofo): Tokelau is UT +13, not +14.
3536 (Thanks to Steffen Thorsen.)
3538 * Use a single version number for both code and data.
3540 * .gitignore: New file.
3542 * Remove trailing white space.
3545 Release code2012c-data2012d - 2012-07-19 16:35:33 -0700
3547 Changes for Morocco's timestamps, which take effect in a couple of
3548 hours, along with infrastructure changes to accommodate how the tz
3549 code and data are released on IANA.
3552 Release data2012c - 2012-03-27 12:17:25 -0400
3555 Summer time changes for Morocco (to start late April 2012)
3558 Changes for 2012 for Gaza & the West Bank (Hebron) and Syria
3561 Haiti following US/Canada rules for 2012 (and we're assuming,
3562 for now anyway, for the future).
3565 Release 2012b - 2012-03-02 12:29:15 +0700
3567 There is just one change to tzcode2012b (compared with 2012a):
3568 the Makefile that was accidentally included with 2012a has been
3569 replaced with the version that should have been there, which is
3570 identical with the previous version (from tzcode2011i).
3572 There are just two changes in tzdata2012b compared with 2012a.
3574 Most significantly, summer time in Cuba has been delayed 3 weeks
3575 (now starts April 1 rather than March 11). Since Mar 11 (the old start
3576 date, as listed in 2012a) is just a little over a week away, this
3579 Less importantly, an excess tab in one of the changes in zone.tab
3580 in 2012a has been removed.
3583 Release 2012a - 2012-03-01 18:28:10 +0700
3585 The changes in tzcode2012a (compared to the previous version, 2011i)
3586 are entirely to the README and tz-art.htm and tz-link.htm files, if
3587 none of those concern you, you can ignore the code update. The changes
3588 reflect the changed addresses for the mailing list and the code and
3589 data distribution points & methods (and a link to DateTime::TimeZone::Tzfile
3590 has been added to tz-link.htm).
3592 In tzdata2012a (compared to the previous release, which was 2011n)
3593 the major changes are:
3594 Chile 2011/2012 and 2012/2013 summer time date adjustments.
3595 Falkland Islands onto permanent summer time (we're assuming for the
3596 foreseeable future, though 2012 is all we're fairly certain of.)
3597 Armenia has abolished Summer Time.
3598 Tokelau jumped the International Date Line back last December
3599 (just the same as their near neighbour, Samoa).
3600 America/Creston is a new zone for a small area of British Columbia
3601 There will be a leapsecond 2012-06-30 23:59:60 UTC.
3603 Other minor changes are:
3604 Corrections to 1918 Canadian summer time end dates.
3605 Updated URL for UK time zone history (in comments)
3606 A few typos in Le Corre's list of free French place names (comments)
3609 Release data2011n - 2011-10-30 14:57:54 +0700
3611 There are three changes of note - most urgently, Cuba (America/Havana)
3612 has extended summer time by two weeks, now to end on Nov 13, rather than
3613 the (already past) Oct 30. Second, the Pridnestrovian Moldavian Republic
3614 (Europe/Tiraspol) decided not to split from the rest of Moldova after
3615 all, and consequently that zone has been removed (again) and reinstated
3616 in the "backward" file as a link to Europe/Chisinau. And third, the
3617 end date for Fiji's summer time this summer was moved forward from the
3618 earlier planned Feb 26, to Jan 22.
3620 Apart from that, Moldova (MD) returns to a single entry in zone.tab
3621 (and the incorrect syntax that was in the 2011m version of that file
3622 is so fixed - it would have been fixed in a different way had this
3623 change not happened - that's the "missing" sccs version id).
3626 Release data2011m - 2011-10-24 21:42:16 +0700
3628 In particular, the typos in comments in the data (2011-11-17 should have
3629 been 2011-10-17 as Alan Barrett noted, and spelling of Tiraspol that
3630 Tim Parenti noted) have been fixed, and the change for Ukraine has been
3631 made in all 4 Ukrainian zones, rather than just Kiev (again, thanks to
3632 Tim Parenti, and also Denys Gavrysh)
3634 In addition, I added Europe/Tiraspol to zone.tab.
3636 This time, all the files have new version numbers... (including the files
3637 otherwise unchanged in 2011m that were changed in 2011l but didn't get new
3638 version numbers there...)
3641 Release data2011l - 2011-10-10 11:15:43 +0700
3643 There are just 2 changes that cause different generated tzdata files from
3644 zic, to Asia/Hebron and Pacific/Fiji - the possible change for Bahia, Brazil
3645 is included, but commented out. Compared with the diff I sent out last week,
3646 this version also includes attributions for the sources for the changes
3647 (in much the same format as ado used, but the html tags have not been
3648 checked, verified, or used in any way at all, so if there are errors there,
3649 please let me know.)
3652 Release data2011k - 2011-09-20 17:54:03 -0400
3657 Release data2011j - 2011-09-12 09:22:49 -0400
3659 (contemporary changes for Samoa; past changes for Kenya, Uganda, and
3660 Tanzania); there are also two spelling corrections to comments in
3661 the australasia file (with thanks to Christos Zoulas).
3664 Release 2011i - 2011-08-29 05:56:32 -0400
3669 Release data2011h - 2011-06-15 18:41:48 -0400
3671 Russia and Curaçao changes
3674 Release 2011g - 2011-04-25 09:07:22 -0400
3676 update the rules for Egypt to reflect its abandonment of DST this year
3679 Release 2011f - 2011-04-06 17:14:53 -0400
3684 Release 2011e - 2011-03-31 16:04:38 -0400
3686 Morocco, Chile, and tz-link changes
3689 Release 2011d - 2011-03-14 09:18:01 -0400
3691 changes that impact present-day timestamps in Cuba, Samoa, and Turkey
3694 Release 2011c - 2011-03-07 09:30:09 -0500
3696 These do affect current timestamps in Chile and Annette Island, Canada.
3699 Release 2011b - 2011-02-07 08:44:50 -0500
3704 Release 2011a - 2011-01-24 10:30:16 -0500
3709 Release data2010o - 2010-11-01 09:18:23 -0400
3711 change to the end of DST in Fiji in 2011
3714 Release 2010n - 2010-10-25 08:19:17 -0400
3719 Release 2010m - 2010-09-27 09:24:48 -0400
3721 Hong Kong, Vostok, and zic.c changes
3724 Release 2010l - 2010-08-16 06:57:25 -0400
3729 Release 2010k - 2010-07-26 10:42:27 -0400
3734 Release 2010j - 2010-05-10 09:07:48 -0400
3736 changes for Bahía de Banderas and for version naming
3739 Release data2010i - 2010-04-16 18:50:45 -0400
3741 the end of DST in Morocco on 2010-08-08
3744 Release data2010h - 2010-04-05 09:58:56 -0400
3749 Release data2010g - 2010-03-24 11:14:53 -0400
3754 Release 2010f - 2010-03-22 09:45:46 -0400
3759 Release data2010e - 2010-03-08 14:24:27 -0500
3761 corrects the Dhaka bug found by Danvin Ruangchan
3764 Release data2010d - 2010-03-06 07:26:01 -0500
3769 Release 2010c - 2010-03-01 09:20:58 -0500
3771 changes including KRE's suggestion for earlier initialization of
3772 "goahead" and "goback" structure elements
3775 Release code2010a - 2010-02-16 10:40:04 -0500
3780 Release data2010b - 2010-01-20 12:37:01 -0500
3785 Release data2010a - 2010-01-18 08:30:04 -0500
3790 Release data2009u - 2009-12-26 08:32:28 -0500
3792 changes to DST in Bangladesh
3795 Release 2009t - 2009-12-21 13:24:27 -0500
3800 Release data2009s - 2009-11-14 10:26:32 -0500
3802 (cosmetic) Antarctica change and the DST-in-Fiji-in-2009-and-2010 change
3805 Release 2009r - 2009-11-09 10:10:31 -0500
3807 "antarctica" and "tz-link.htm" changes
3810 Release 2009q - 2009-11-02 09:12:40 -0500
3812 with two corrections as reported by Eric Muller and Philip Newton
3815 Release data2009p - 2009-10-23 15:05:27 -0400
3817 Argentina (including San Luis) changes (with the correction from
3821 Release data2009o - 2009-10-14 16:49:38 -0400
3823 Samoa (commentary only), Pakistan, and Bangladesh changes
3826 Release data2009n - 2009-09-22 15:13:38 -0400
3828 added commentary for Argentina and a change to the end of DST in
3832 Release data2009m - 2009-09-03 10:23:43 -0400
3834 Samoa and Palestine changes
3837 Release data2009l - 2009-08-14 09:13:07 -0400
3839 Samoa (comments only) and Egypt
3842 Release 2009k - 2009-07-20 09:46:08 -0400
3847 Release data2009j - 2009-06-15 06:43:59 -0400
3849 Bangladesh change (with a short turnaround since the DST change is
3853 Release 2009i - 2009-06-08 09:21:22 -0400
3855 updating for DST in Bangladesh this year
3858 Release 2009h - 2009-05-26 09:19:14 -0400
3863 Release data2009g - 2009-04-20 16:34:07 -0400
3868 Release data2009f - 2009-04-10 11:00:52 -0400
3870 correct DST in Pakistan
3873 Release 2009e - 2009-04-06 09:08:11 -0400
3878 Release 2009d - 2009-03-23 09:38:12 -0400
3880 Morocco, Tunisia, Argentina, and American Astronomical Society changes
3883 Release data2009c - 2009-03-16 09:47:51 -0400
3885 change to the start of Cuban DST
3888 Release 2009b - 2009-02-09 11:15:22 -0500
3893 Release 2009a - 2009-01-21 10:09:39 -0500
3898 Release data2008i - 2008-10-21 12:10:25 -0400
3900 southamerica and zone.tab files, with Argentina DST rule changes and
3901 United States zone reordering and recommenting
3904 Release 2008h - 2008-10-13 07:33:56 -0400
3909 Release 2008g - 2008-10-06 09:03:18 -0400
3911 Fix a broken HTML anchor and update Brazil's DST transitions;
3912 there's also a slight reordering of information in tz-art.htm.
3915 Release data2008f - 2008-09-09 22:33:26 -0400
3920 Release 2008e - 2008-07-28 14:11:17 -0400
3922 changes by Arthur David Olson and Jesper Nørgaard Welen
3925 Release data2008d - 2008-07-07 09:51:38 -0400
3927 changes by Arthur David Olson, Paul Eggert, and Rodrigo Severo
3930 Release data2008c - 2008-05-19 17:48:03 -0400
3932 Pakistan, Morocco, and Mongolia
3935 Release data2008b - 2008-03-24 08:30:59 -0400
3937 including renaming Asia/Calcutta to Asia/Kolkata, with a backward
3941 Release 2008a - 2008-03-08 05:42:16 -0500
3946 Release 2007k - 2007-12-31 10:25:22 -0500
3948 most importantly, changes to the "southamerica" file based on
3949 Argentina's readoption of daylight saving time
3952 Release 2007j - 2007-12-03 09:51:01 -0500
3954 1. eliminate the "P" (parameter) macro;
3956 2. the "noncontroversial" changes circulated on the time zone
3957 mailing list (less the changes to "logwtmp.c");
3959 3. eliminate "too many transition" errors when "min" is used in time
3962 4. changes by Paul Eggert (including updated information for Venezuela).
3965 Release data2007i - 2007-10-30 10:28:11 -0400
3967 changes for Cuba and Syria
3970 Release 2007h - 2007-10-01 10:05:51 -0400
3972 changes by Paul Eggert, as well as an updated link to the ICU
3973 project in tz-link.htm
3976 Release 2007g - 2007-08-20 10:47:59 -0400
3978 changes by Paul Eggert
3980 The "leapseconds" file has been updated to incorporate the most
3981 recent International Earth Rotation and Reference Systems Service
3984 There's an addition to tz-art.htm regarding the television show "Medium".
3987 Release 2007f - 2007-05-07 10:46:46 -0400
3989 changes by Paul Eggert (including Haiti, Turks and Caicos, and New
3992 changes to zic.c to allow hour values greater than 24 (along with
3993 Paul's improved time value overflow checking)
3996 Release 2007e - 2007-04-02 10:11:52 -0400
3998 Syria and Honduras changes by Paul Eggert
4000 zic.c variable renaming changes by Arthur David Olson
4003 Release 2007d - 2007-03-20 08:48:30 -0400
4005 changes by Paul Eggert
4007 the elimination of white space at the ends of lines
4010 Release 2007c - 2007-02-26 09:09:37 -0500
4012 changes by Paul Eggert
4015 Release 2007b - 2007-02-12 09:34:20 -0500
4017 Paul Eggert's proposed change to the quotation handling logic in zic.c.
4019 changes to the commentary in "leapseconds" reflecting the IERS
4020 announcement that there is to be no positive leap second at the end
4024 Release 2007a - 2007-01-08 12:28:29 -0500
4026 changes by Paul Eggert
4028 Derick Rethan's Asmara change
4030 Oscar van Vlijmen's Easter Island local mean time change
4032 symbolic link changes
4035 Release 2006p - 2006-11-27 08:54:27 -0500
4037 changes by Paul Eggert
4040 Release 2006o - 2006-11-06 09:18:07 -0500
4042 changes by Paul Eggert
4045 Release 2006n - 2006-10-10 11:32:06 -0400
4047 changes by Paul Eggert
4050 Release 2006m - 2006-10-02 15:32:35 -0400
4052 changes for Uruguay, Palestine, and Egypt by Paul Eggert
4054 (minimalist) changes to zic.8 to clarify "until" information
4057 Release data2006l - 2006-09-18 12:58:11 -0400
4059 Paul's best-effort work on this coming weekend's Egypt time change
4062 Release 2006k - 2006-08-28 12:19:09 -0400
4064 changes by Paul Eggert
4067 Release 2006j - 2006-08-21 09:56:32 -0400
4069 changes by Paul Eggert
4072 Release code2006i - 2006-08-07 12:30:55 -0400
4076 Ken Pizzini's conversion script
4079 Release code2006h - 2006-07-24 09:19:37 -0400
4081 adds public domain notices to four files
4083 includes a fix for transition times being off by a second
4085 adds a new recording to the "arts" file (information courtesy Colin Bowern)
4088 Release 2006g - 2006-05-08 17:18:09 -0400
4090 northamerica changes by Paul Eggert
4093 Release 2006f - 2006-05-01 11:46:00 -0400
4095 a missing version number problem is fixed (with thanks to Bradley
4096 White for catching the problem)
4099 Release 2006d - 2006-04-17 14:33:43 -0400
4101 changes by Paul Eggert
4103 added new items to tz-arts.htm that were found by Paul
4106 Release 2006c - 2006-04-03 10:09:32 -0400
4108 two sets of data changes by Paul Eggert
4110 a fencepost error fix in zic.c
4112 changes to zic.c and the "europe" file to minimize differences
4113 between output produced by the old 32-bit zic and the new 64-bit
4117 Release 2006b - 2006-02-20 10:08:18 -0500
4118 [tz32code2006b + tz64code2006b + tzdata2006b]
4122 All SCCS IDs were bumped to "8.1" for this release.
4125 Release 2006a - 2006-01-30 08:59:31 -0500
4127 changes by Paul Eggert (in particular, Indiana time zone moves)
4129 an addition to the zic manual page to describe how special-case
4130 transitions are handled
4133 Release 2005r - 2005-12-27 09:27:13 -0500
4135 Canadian changes by Paul Eggert
4137 They also add "<pre>" directives to time zone data files and reflect
4138 changes to warning message logic in "zdump.c" (but with calls to
4139 "gettext" kept unbundled at the suggestion of Ken Pizzini).
4142 Release 2005q - 2005-12-13 09:17:09 -0500
4144 Nothing earth-shaking here:
4145 1. Electronic mail addresses have been removed.
4146 2. Casts of the return value of exit have been removed.
4147 3. Casts of the argument of is.* macros have been added.
4148 4. Indentation in one section of zic.c has been fixed.
4149 5. References to dead URLs in the data files have been dealt with.
4152 Release 2005p - 2005-12-05 10:30:53 -0500
4154 "systemv", "tz-link.htm", and "zdump.c" changes
4155 (less the casts of arguments to the is* macros)
4158 Release 2005o - 2005-11-28 10:55:26 -0500
4160 Georgia, Cuba, Nicaragua, and Jordan changes by Paul Eggert
4162 zdump.c lint fixes by Arthur David Olson
4165 Release 2005n - 2005-10-03 09:44:09 -0400
4167 changes by Paul Eggert (both the Uruguay changes and the Kyrgyzstan
4171 Release 2005m - 2005-08-29 12:15:40 -0400
4173 changes by Paul Eggert (with a small tweak to the tz-art change)
4175 a declaration of an unused variable has been removed from zdump.c
4178 Release 2005l - 2005-08-22 12:06:39 -0400
4180 changes by Paul Eggert
4182 overflow/underflow checks by Arthur David Olson, minus changes to
4183 the "Theory" file about the pending addition of 64-bit data (I grow
4184 less confident of the changes being accepted with each passing day,
4185 and the changes no longer increase the data files nine-fold--there's
4186 less than a doubling in size by my local Sun's reckoning)
4189 Release 2005k - 2005-07-14 14:14:24 -0400
4191 The "leapseconds" file has been edited to reflect the recently
4192 announced leap second at the end of 2005.
4194 I've also deleted electronic mail addresses from the files as an
4198 Release 2005j - 2005-06-13 14:34:13 -0400
4200 These reflect changes to limit the length of time zone abbreviations
4201 and the characters used in those abbreviations.
4203 There are also changes to handle POSIX-style "quoted" timezone
4204 environment variables.
4206 The changes were circulated on the time zone mailing list; the only
4207 change since then was the removal of a couple of minimum-length of
4208 abbreviation checks.
4211 Release data2005i - 2005-04-21 15:04:16 -0400
4213 changes (most importantly to Nicaragua and Haiti) by Paul Eggert
4216 Release 2005h - 2005-04-04 11:24:47 -0400
4218 changes by Paul Eggert
4220 minor changes to Makefile and zdump.c to produce more useful output
4221 when doing a "make typecheck"
4224 Release 2005g - 2005-03-14 10:11:21 -0500
4226 changes by Paul Eggert (a change to current DST rules in Uruguay and
4227 an update to a link to time zone software)
4230 Release 2005f - 2005-03-01 08:45:32 -0500
4232 data and documentation changes by Paul Eggert
4235 Release 2005e - 2005-02-10 15:59:44 -0500
4240 Release code2005d - 2005-01-31 09:21:47 -0500
4242 make zic complain about links to links if the -v flag is used
4244 have "make public" do more code checking
4246 add an include to "localtime.c" for the benefit of gcc systems
4249 Release 2005c - 2005-01-17 18:36:29 -0500
4251 get better results when mktime runs on a system where time_t is double
4253 changes to the data files (most importantly to Paraguay)
4256 Release 2005b - 2005-01-10 09:19:54 -0500
4258 Get localtime and gmtime working on systems with exotic time_t types.
4260 Update the leap second commentary in the "leapseconds" file.
4263 Release 2005a - 2005-01-01 13:13:44 -0500
4268 Release code2004i - 2004-12-14 13:42:58 -0500
4270 Deal with systems where time_t is unsigned.
4273 Release code2004h - 2004-12-07 11:40:18 -0500
4275 64-bit-time_t changes
4278 Release 2004g - 2004-11-02 09:06:01 -0500
4280 update to Cuba (taking effect this weekend)
4282 other changes by Paul Eggert
4284 correction of the spelling of Oslo
4286 changed versions of difftime.c and private.h
4289 Release code2004f - 2004-10-21 10:25:22 -0400
4291 Cope with wide-ranging tm_year values.
4294 Release 2004e - 2004-10-11 14:47:21 -0400
4296 Brazil/Argentina/Israel changes by Paul Eggert
4298 changes to tz-link.htm by Paul
4300 one small fix to Makefile
4303 Release 2004d - 2004-09-22 08:27:29 -0400
4305 Avoid overflow problems when TM_YEAR_BASE is added to an integer.
4308 Release 2004c - 2004-08-11 12:06:26 -0400
4310 asctime-related changes
4312 (variants of) some of the documentation changes suggested by Paul Eggert
4315 Release 2004b - 2004-07-19 14:33:35 -0400
4317 data changes by Paul Eggert - most importantly, updates for Argentina
4320 Release 2004a - 2004-05-27 12:00:47 -0400
4322 changes by Paul Eggert
4324 Handle DST transitions that occur at the end of a month in some
4325 years but at the start of the following month in other years.
4327 Add a copy of the correspondence that's the basis for claims about
4328 DST in the Navajo Nation.
4331 Release 2003e - 2003-12-15 09:36:47 -0500
4333 changes by Arthur David Olson (primarily code changes)
4335 changes by Paul Eggert (primarily data changes)
4337 minor changes to "Makefile" and "northamerica" (in the latter case,
4338 optimization of the "Toronto" rules)
4341 Release 2003d - 2003-10-06 09:34:44 -0400
4343 changes by Paul Eggert
4346 Release 2003c - 2003-09-16 10:47:05 -0400
4348 Fix bad returns in zic.c's inleap function.
4349 Thanks to Bradley White for catching the problem!
4352 Release 2003b - 2003-09-16 07:13:44 -0400
4354 Add a "--version" option (and documentation) to the zic and zdump commands.
4356 changes to overflow/underflow checking in zic
4358 a localtime typo fix.
4360 Update the leapseconds and tz-art.htm files.
4363 Release 2003a - 2003-03-24 09:30:54 -0500
4365 changes by Paul Eggert
4367 a few additions and modifications to the tz-art.htm file
4370 Release 2002d - 2002-10-15 13:12:42 -0400
4372 changes by Paul Eggert, less the "Britain (UK)" change in iso3166.tab
4374 There's also a new time zone quote in "tz-art.htm".
4377 Release 2002c - 2002-04-04 11:55:20 -0500
4379 changes by Paul Eggert
4381 Change zic.c to avoid creating symlinks to files that don't exist.
4384 Release 2002b - 2002-01-28 12:56:03 -0500
4386 [These change notes are for Release 2002a, which was corrupted.
4387 2002b was a corrected version of 2002a.]
4389 changes by Paul Eggert
4391 Update the "leapseconds" file to note that there'll be no leap
4392 second at the end of June, 2002.
4394 Change "zic.c" to deal with a problem in handling the "Asia/Bishkek" zone.
4396 Change to "difftime.c" to avoid sizeof problems.
4399 Release 2001d - 2001-10-09 13:31:32 -0400
4401 changes by Paul Eggert
4404 Release 2001c - 2001-06-05 13:59:55 -0400
4406 changes by Paul Eggert and Andrew Brown
4409 Release 2001b - 2001-04-05 16:44:38 -0400
4411 changes by Paul Eggert (modulo jnorgard's typo fix)
4413 tz-art.htm has been HTMLified.
4416 Release 2001a - 2001-03-13 12:57:44 -0500
4418 changes by Paul Eggert
4420 An addition to the "leapseconds" file: comments with the text of the
4421 latest IERS leap second notice.
4423 Trailing white space has been removed from data file lines, and
4424 repeated spaces in "Rule Jordan" lines in the "asia" file have been
4428 Release 2000h - 2000-12-14 15:33:38 -0500
4430 changes by Paul Eggert
4432 one typo fix in the "art" file
4434 With providence, this is the last update of the millennium.
4437 Release 2000g - 2000-10-10 11:35:22 -0400
4439 changes by Paul Eggert
4441 correction of John Mackin's name submitted by Robert Elz
4443 Garry Shandling's Daylight Saving Time joke (!?!) from the recent
4444 Emmy Awards broadcast.
4447 Release 2000f - 2000-08-10 09:31:58 -0400
4449 changes by Paul Eggert
4451 Added information in "tz-art.htm" on a Seinfeld reference to DST.
4453 Error checking and messages in the "yearistype" script have been
4457 Release 2000e - 2000-07-31 09:27:54 -0400
4459 data changes by Paul Eggert
4461 a change to the default value of the defined constant HAVE_STRERROR
4463 the addition of a Dave Barry quote on DST to the tz-arts file
4466 Release 2000d - 2000-04-20 15:43:04 -0400
4468 changes to the documentation and code of strftime for C99 conformance
4470 a bug fix for date.c
4472 These are based on (though modified from) changes by Paul Eggert.
4475 Release 2000c - 2000-03-04 10:31:43 -0500
4477 changes by Paul Eggert
4480 Release 2000b - 2000-02-21 12:16:29 -0500
4482 changes by Paul Eggert and Joseph Myers
4484 modest tweaks to the tz-art.htm and tz-link.htm files
4487 Release 2000a - 2000-01-18 09:21:26 -0500
4489 changes by Paul Eggert
4491 The two hypertext documents have also been renamed.
4494 Release code1999i-data1999j - 1999-11-15 18:43:22 -0500
4496 Paul Eggert's changes
4498 additions to the "zic" manual page and the "Arts.htm" file
4501 Release code1999h-data1999i - 1999-11-08 14:55:21 -0500
4506 Release data1999h - 1999-10-07 03:50:29 -0400
4508 changes by Paul Eggert to "europe" (most importantly, fixing
4509 Lithuania and Estonia)
4512 Release 1999g - 1999-09-28 11:06:18 -0400
4514 data changes by Paul Eggert (most importantly, the change for
4515 Lebanon that buys correctness for this coming Sunday)
4517 The "code" file contains changes to "Makefile" and "checktab.awk" to
4518 allow better checking of time zone files before they are published.
4521 Release 1999f - 1999-09-23 09:48:14 -0400
4523 changes by Arthur David Olson and Paul Eggert
4526 Release 1999e - 1999-08-17 15:20:54 -0400
4528 changes circulated by Paul Eggert, although the change to handling
4529 of DST-specifying timezone names has been commented out for now
4530 (search for "XXX" in "localtime.c" for details). These files also
4531 do not make any changes to the start of DST in Brazil.
4533 In addition to Paul's changes, there are updates to "Arts.htm" and
4537 Release 1999d - 1999-03-30 11:31:07 -0500
4539 changes by Paul Eggert
4541 The Makefile's "make public" rule has also been changed to do a test
4542 compile of each individual time zone data file (which should help
4543 avoid problems such as the one we had with Nicosia).
4546 Release 1999c - 1999-03-25 09:47:47 -0500
4548 changes by Paul Eggert, most importantly the change for Chile.
4551 Release 1999b - 1999-02-01 17:51:44 -0500
4553 changes by Paul Eggert
4555 code changes (suggested by Mani Varadarajan, mani at be.com) for
4556 correct handling of symbolic links when building using a relative directory
4558 code changes to generate correct messages for failed links
4560 updates to the URLs in Arts.htm
4563 Release 1999a - 1999-01-19 16:20:29 -0500
4565 error message internationalizations and corrections in zic.c and
4566 zdump.c (as suggested by Vladimir Michl, vladimir.michl at upol.cz,
4570 Release code1998h-data1998i - 1998-10-01 09:56:10 -0400
4572 changes for Brazil, Chile, and Germany
4574 support for use of "24:00" in the input files for the time zone compiler
4577 Release code1998g-data1998h - 1998-09-24 10:50:28 -0400
4579 changes by Paul Eggert
4581 correction to a define in the "private.h" file
4584 Release data1998g - 1998-08-11 03:28:35 -0000
4585 [tzdata1998g.tar.gz is missing!]
4587 Lithuanian change provided by mgedmin at pub.osf.it
4589 Move creation of the GMT link with Etc/GMT to "etcetera" (from
4590 "backward") to ensure that the GMT file is created even where folks
4591 don't want the "backward" links (as suggested by Paul Eggert).
4594 Release data1998f - 1998-07-20 13:50:00 -0000
4595 [tzdata1998f.tar.gz is missing!]
4597 Update the "leapseconds" file to include the newly-announced
4598 insertion at the end of 1998.
4601 Release code1998f - 1998-06-01 10:18:31 -0400
4603 addition to localtime.c by Guy Harris
4606 Release 1998e - 1998-05-28 09:56:26 -0400
4608 The Makefile is changed to produce zoneinfo-posix rather than
4609 zoneinfo/posix, and to produce zoneinfo-leaps rather than
4612 data changes by Paul Eggert
4614 changes from Guy Harris to provide asctime_r and ctime_r
4616 A usno1998 file (substantially identical to usno1997) has been added.
4619 Release 1998d - 1998-05-14 11:58:34 -0400
4621 changes to comments (in particular, elimination of references to CIA maps).
4622 "Arts.htm", "WWW.htm", "asia", and "australasia" are the only places
4623 where changes occur.
4626 Release 1998c - 1998-02-28 12:32:26 -0500
4628 changes by Paul Eggert (save the "French correction," on which I'll
4629 wait for the dust to settle)
4633 changes and additions to Arts.htm
4636 Release 1998b - 1998-01-17 14:31:51 -0500
4638 URL cleanups and additions
4641 Release 1998a - 1998-01-13 12:37:35 -0500
4643 changes by Paul Eggert
4646 Release code1997i-data1997k - 1997-12-29 09:53:41 -0500
4648 changes by Paul Eggert, with minor modifications from Arthur David
4649 Olson to make the files more browser friendly
4652 Release code1997h-data1997j - 1997-12-18 17:47:35 -0500
4654 minor changes to put "TZif" at the start of each timezone information file
4656 a rule has also been added to the Makefile so you can
4658 to just recompile the zone information files (rather than doing a
4659 full "make install" with its other effects).
4662 Release data1997i - 1997-10-07 08:45:38 -0400
4664 changes to Africa by Paul Eggert
4667 Release code1997g-data1997h - 1997-09-04 16:56:54 -0400
4669 corrections for Uruguay (and other locations)
4671 Arthur David Olson's simple-minded fix allowing mktime to both
4672 correctly handle leap seconds and correctly handle tm_sec values
4673 upon which arithmetic has been performed.
4676 Release code1997f-data1997g - 1997-07-19 13:15:02 -0400
4678 Paul Eggert's updates
4680 a small change to a function prototype;
4682 "Music" has been renamed "Arts.htm", HTMLified, and augmented to
4683 include information on Around the World in Eighty Days.
4686 Release code1997e-data1997f - 1997-05-03 18:52:34 -0400
4688 fixes to zic's error handling
4690 changes inspired by the item circulated on Slovenia
4692 The description of Web resources has been HTMLified for browsing
4695 A new piece of tz-related music has been added to the "Music" file.
4698 Release code1997d-data1997e - 1997-03-29 12:48:52 -0500
4700 Paul Eggert's latest suggestions
4703 Release code1997c-data1997d - 1997-03-07 20:37:54 -0500
4705 changes to "zic.c" to correct performance of the "-s" option
4707 a new file "usno1997"
4710 Release data1997c - 1997-03-04 09:58:18 -0500
4715 Release 1997b - 1997-02-27 18:34:19 -0500
4717 The data file incorporates the 1997 leap second.
4719 The code file incorporates Arthur David Olson's take on the
4720 zic/multiprocessor/directory-creation situation.
4723 Release 1997a - 1997-01-21 09:11:10 -0500
4725 Paul Eggert's Antarctica (and other changes)
4727 Arthur David Olson finessed the "getopt" issue by checking against
4728 both -1 and EOF (regardless of POSIX, SunOS 4.1.1's manual says -1
4729 is returned while SunOS 5.5's manual says EOF is returned).
4732 Release code1996o-data1996n - 1996-12-27 21:42:05 -0500
4734 Paul Eggert's latest changes
4737 Release code1996n - 1996-12-16 09:42:02 -0500
4739 link snapping fix from Bruce Evans (via Garrett Wollman)
4742 Release data1996m - 1996-11-24 02:37:34 -0000
4743 [tzdata1996m.tar.gz is missing!]
4745 Paul Eggert's batch of changes
4748 Release code1996m-data1996l - 1996-11-05 14:00:12 -0500
4750 No functional changes here; the files have simply been changed to
4751 make more use of ISO style dates in comments. The names of the above
4752 files now include the year in full.
4755 Release code96l - 1996-09-08 17:12:20 -0400
4757 tzcode96k was missing a couple of pieces.
4760 Release 96k - 1996-09-08 16:06:22 -0400
4762 the latest round of changes from Paul Eggert
4764 the recent Year 2000 material
4767 Release code96j - 1996-07-30 13:18:53 -0400
4769 Set sp->typecnt as suggested by Timothy Patrick Murphy.
4772 Release code96i - 1996-07-27 20:11:35 -0400
4774 Paul's suggested patch for strftime %V week numbers
4777 Release data96i - 1996-07-01 18:13:04 -0400
4779 "northamerica" and "europe" changes by Paul Eggert
4782 Release code96h - 1996-06-05 08:02:21 -0400
4784 fix for handling transitions specified in Universal Time
4786 Some "public domain" notices have also been added.
4789 Release code96g - 1996-05-16 14:00:26 -0400
4791 fix for the simultaneous-DST-and-zone-change challenge
4794 Release data96h - 1996-05-09 17:40:51 -0400
4796 changes by Paul Eggert
4799 Release code96f-data96g - 1996-05-03 03:09:59 -0000
4800 [tzcode96f.tar.gz + tzdata96g.tar.gz are both missing!]
4802 The changes get us some of the way to fixing the problems noted in Paul
4803 Eggert's letter yesterday (in addition to a few others). The approach
4804 has been to make zic a bit smarter about figuring out what time zone
4805 abbreviations apply just after the time specified in the "UNTIL" part
4806 of a zone line. Putting the smarts in zic means avoiding having
4807 transition times show up in both "Zone" lines and "Rule" lines, which
4808 in turn avoids multiple transition time entries in time zone files.
4809 (This also makes the zic input files such as "europe" a bit shorter and
4810 should ease maintenance.)
4813 Release data96f - 1996-04-19 19:20:03 -0000
4814 [tzdata96f.tar.gz is missing!]
4816 The only changes are to the "northamerica" file; the time zone
4817 abbreviation for Denver is corrected to MST (and MDT), and the
4818 comments for Mexico have been updated.
4821 Release data96e - 1996-03-19 17:37:26 -0500
4823 Proposals by Paul Eggert, in particular the Portugal change that
4824 comes into play at the end of this month.
4827 Release data96d - 1996-03-18 20:49:39 -0500
4832 Release code96e - 1996-02-29 15:43:27 -0000
4833 [tzcode96e.tar.gz is missing!]
4835 internationalization changes and the fix to the documentation for strftime
4838 Release code96d-data96c - 1996-02-12 11:05:27 -0500
4840 The "code" file simply updates Bob Kridle's electronic address.
4842 The "data" file updates rules for Mexico.
4845 Release data96b - 1996-01-27 15:44:42 -0500
4850 Release code96c - 1996-01-16 16:58:15 -0500
4852 leap-year streamlining and binary-search changes
4857 Release code96b - 1996-01-10 20:42:39 -0500
4859 fixes and enhancements from Paul Eggert, including code that
4860 emulates the behavior of recent versions of the SunOS "date"
4864 Release 96a - 1996-01-06 09:08:24 -0500
4868 fixes to strftime.c for correct ISO 8601 week number generation,
4869 plus support for two new formats ('G' and 'g') to give ISO 8601 year
4870 numbers (which are not necessarily the same as calendar year numbers)
4873 Release code95i-data95m - 1995-12-21 12:46:47 -0500
4875 The latest revisions from Paul Eggert are included, the usno1995
4876 file has been updated, and a new file ("WWW") covering useful URLs
4880 Release code95h-data95l - 1995-12-19 18:10:12 -0500
4882 A simplification of a macro definition, a change to data for Sudan,
4883 and (for last minute shoppers) notes in the "Music" file on the CD
4887 Release code95g-data95k - 1995-10-30 10:32:47 -0500
4889 (slightly reformatted) 8-bit-clean proposed patch
4891 minor patch: US/Eastern -> America/New_York
4893 snapshot of the USNO's latest data ("usno1995")
4895 some other minor cleanups
4898 Release code95f-data95j - 1995-10-28 21:01:34 -0000
4899 [tzcode95f.tar.gz + tzdata95j.tar.gz are both missing!]
4903 support for 64-bit time_t's
4905 optimization in localtime.c
4908 Release code95e - 1995-10-13 13:23:57 -0400
4910 the mktime change to scan from future to past when trying to find time zone
4914 Release data95i - 1995-09-26 10:43:26 -0400
4916 For Canada/Central, guess that the Sun customer's "one week too
4917 early" was just a approximation, and the true error is one month
4918 too early. This is consistent with the rest of Canada.
4921 Release data95h - 1995-09-21 11:26:48 -0400
4923 latest changes from Paul Eggert
4926 Release code95d - 1995-09-14 11:14:45 -0400
4928 the addition of a "Music" file, which documents four recorded
4929 versions of the tune "Save That Time".
4932 Release data95g - 1995-09-01 17:21:36 -0400
4934 "yearistype" correction
4937 Release data95f - 1995-08-28 20:46:56 -0400
4939 Paul Eggert's change to the australasia file
4942 Release data95e - 1995-07-08 18:02:34 -0400
4944 The only change is a leap second at the end of this year.
4945 Thanks to Bradley White for forwarding news on the leap second.
4948 Release data95d - 1995-07-03 13:26:22 -0400
4950 Paul Eggert's changes
4953 Release data95c - 1995-07-02 19:19:28 -0400
4955 changes to "asia", "backward", "europe", and "southamerica"
4956 (read: northamericacentrics need not apply)
4959 Release code95c - 1995-03-13 14:00:46 -0500
4961 one-line fix for sign extension problems in detzcode
4964 Release 95b - 1995-03-04 11:22:38 -0500
4966 Minor changes in both:
4968 The "code" file contains a workaround for the lack of "unistd.h" in
4969 Microsoft C++ version 7.
4971 The "data" file contains a fixed "Link" for America/Shiprock.
4974 Release 94h - 1994-12-10 12:51:14 -0500
4978 * incorporate the changes to "zdump" and "date" to make changes to
4979 the "TZ" environment variable permanent;
4981 * incorporate the table changes by Paul Eggert;
4983 * include (and document) support for universal time specifications in
4984 data files - but do not (yet) include use of this feature in the
4987 Think of this as "TZ Classic" - the software has been set up not to break if
4988 universal time shows up in its input, and data entries have been
4989 left as is so as not to break existing implementations.
4992 Release data94f - 1994-08-20 12:56:09 -0400
4994 (with thanks!) the latest data updates from Paul Eggert
4997 Release data94e - 1994-06-04 13:13:53 -0400
5002 Release code94g - 1994-05-05 12:14:07 -0400
5004 fix missing "optind.c" and a reference to it in the Makefile
5007 Release code94f - 1994-05-05 13:00:33 -0000
5008 [tzcode94f.tar.gz is missing!]
5010 changes to avoid overflow in difftime, as well as changes to cope
5011 with the 52/53 challenge in strftime
5014 Release code94e - 1994-03-30 23:32:59 -0500
5016 change for the benefit of PCTS
5019 Release 94d - 1994-02-24 15:42:25 -0500
5021 Avoid clashes with POSIX semantics for zones such as GMT+4.
5023 Some other very minor housekeeping is also present.
5026 Release code94c - 1994-02-10 08:52:40 -0500
5028 Fix bug where mkdirs was broken unless you compile with
5029 -fwritable-strings (which is generally losing to do).
5032 Release 94b - 1994-02-07 10:04:33 -0500
5034 work by Paul Eggert who notes:
5036 I found another book of time zone histories by E W Whitman; it's not
5037 as extensive as Shanks but has a few goodies of its own. I used it
5038 to update the tables. I also fixed some more as a result of
5039 correspondence with Adam David and Peter Ilieve, and move some stray
5040 links from 'europe' to 'backward'. I corrected some scanning errors
5043 As far as the code goes, I fixed zic to allow years in the range
5044 INT_MIN to INT_MAX; this fixed a few boundary conditions around 1900.
5045 And I cleaned up the zic documentation a little bit.
5048 Release data94a - 1994-02-03 08:58:54 -0500
5050 It simply incorporates the recently announced leap second into the
5054 Release 93g - 1993-11-22 17:28:27 -0500
5056 Paul Eggert has provided a good deal of historic information (based
5057 on Shanks), and there are some code changes to deal with the buglets
5058 that crawled out in dealing with the new information.
5061 Release 93f - 1993-10-15 12:27:46 -0400
5063 Paul Eggert's changes
5066 Release 93e - 1993-09-05 21:21:44 -0400
5068 This has updated data for Israel, England, and Kwajalein. There's
5069 also an update to "zdump" to cope with Kwajalein's 24-hour jump.
5070 Thanks to Paul Eggert and Peter Ilieve for the changes.
5073 Release 93d - 1993-06-17 23:34:17 -0400
5075 new fix and new data on Israel
5078 Release 93c - 1993-06-06 19:31:55 -0400
5083 Release 93b - 1993-02-02 14:53:58 -0500
5085 updated "leapseconds" file
5088 Release 93 - 1993-01-08 07:01:06 -0500
5090 At kre's suggestion, the package has been split in two - a code piece
5091 (which also includes documentation) that's only of use to folks who
5092 want to recompile things and a data piece useful to anyone who can
5095 The new version has a few changes to the data files, a few
5096 portability changes, and an off-by-one fix (with thanks to
5097 Tom Karzes at deshaw.com for providing a description and a
5101 Release 92c - 1992-11-21 17:35:36 -0000
5102 [tz92c.tar.Z is missing!]
5104 The fallout from the latest round of DST transitions.
5106 There are changes for Portugal, Saskatchewan, and "Pacific-New";
5107 there's also a change to "zic.c" that makes it portable to more systems.
5110 Release 92 - 1992-04-25 18:17:03 -0000
5111 [tz92.tar.Z is missing!]
5113 By popular demand (well, at any rate, following a request by kre at munnari)
5116 The 1989 update of the time zone package featured:
5118 * POSIXization (including interpretation of POSIX-style TZ environment
5119 variables, provided by Guy Harris),
5120 * ANSIfication (including versions of "mktime" and "difftime"),
5121 * SVIDulation (an "altzone" variable)
5122 * MACHination (the "gtime" function)
5123 * corrections to some time zone data (including corrections to the rules
5124 for Great Britain and New Zealand)
5125 * reference data from the United States Naval Observatory for folks who
5126 want to do additional time zones
5127 * and the 1989 data for Saudi Arabia.
5129 (Since this code will be treated as "part of the implementation" in some
5130 places and as "part of the application" in others, there's no good way to
5131 name functions, such as timegm, that are not part of the proposed ANSI C
5132 standard; such functions have kept their old, underscore-free names in this
5135 And the "dysize" function has disappeared; it was present to allow
5136 compilation of the "date" command on old BSD systems, and a version of "date"
5137 is now provided in the package. The "date" command is not created when you
5138 "make all" since it may lack options provided by the version distributed with
5139 your operating system, or may not interact with the system in the same way
5140 the native version does.
5142 Since POSIX frowns on correct leap second handling, the default behavior of
5143 the "zic" command (in the absence of a "-L" option) has been changed to omit
5144 leap second information from its output files.
5150 This file contains copies of the part of each release announcement
5151 that talks about the changes in that release. The text has been
5152 adapted and reformatted for the purposes of this file.
5154 Traditionally a release R consists of a pair of tarball files,
5155 tzcodeR.tar.gz and tzdataR.tar.gz. However, some releases (e.g.,
5156 code2010a, data2012c) consist of just one or the other tarball, and a
5157 few (e.g., code2012c-data2012d) have tarballs with mixed version
5158 numbers. Recent releases also come in an experimental format
5159 consisting of a single tarball tzdb-R.tar.lz with extra data.
5161 Release timestamps are taken from the release's commit (for newer,
5162 Git-based releases), from the newest file in the tarball (for older
5163 releases, where this info is available) or from the email announcing
5164 the release (if all else fails; these are marked with a time zone
5165 abbreviation of -0000 and an "is missing!" comment).
5167 Earlier versions of the code and data were not announced on the tz
5168 list and are not summarized here.
5170 This file is in the public domain.
projects / FreeBSD / FreeBSD.git / blob