1 News for the tz database
3 Release 2020b - 2020-10-06 18:35:04 -0700
6 Revised predictions for Morocco's changes starting in 2023.
7 Canada's Yukon changes to -07 on 2020-11-01, not 2020-03-08.
8 Macquarie Island has stayed in sync with Tasmania since 2011.
9 Casey, Antarctica is at +08 in winter and +11 in summer.
10 zic no longer supports -y, nor the TYPE field of Rules.
12 Changes to future timestamps
14 Morocco's spring-forward after Ramadan is now predicted to occur
15 no sooner than two days after Ramadan, instead of one day.
16 (Thanks to Milamber.) The first altered prediction is for 2023,
17 now predicted to spring-forward on April 30 instead of April 23.
19 Changes to past and future timestamps
21 Casey Station, Antarctica has been using +08 in winter and +11 in
22 summer since 2018. The most recent transition from +08 to +11 was
23 2020-10-04 00:01. Also, Macquarie Island has been staying in
24 sync with Tasmania since 2011. (Thanks to Steffen Thorsen.)
26 Changes to past and future time zone abbreviations and DST flags
28 Canada's Yukon, represented by America/Whitehorse and
29 America/Dawson, changes its time zone rules from -08/-07 to
30 permanent -07 on 2020-11-01, not on 2020-03-08 as 2020a had it.
31 This change affects only the time zone abbreviation (MST vs PDT)
32 and daylight saving flag for the period between the two dates.
33 (Thanks to Andrew G. Smith.)
35 Changes to past timestamps
37 Correct several transitions for Hungary for 1918/1983.
38 For example, the 1983-09-25 fall-back was at 01:00, not 03:00.
39 (Thanks to Géza Nyáry.) Also, the 1890 transition to standard
40 time was on 11-01, not 10-01 (thanks to Michael Deckers).
42 The 1891 French transition was on March 16, not March 15. The
43 1911-03-11 French transition was at midnight, not a minute later.
44 Monaco's transitions were on 1892-06-01 and 1911-03-29, not
45 1891-03-15 and 1911-03-11. (Thanks to Michael Deckers.)
49 Support for zic's long-obsolete '-y YEARISTYPE' option has been
50 removed and, with it, so has support for the TYPE field in Rule
51 lines, which is now reserved for compatibility with earlier zic.
52 These features were previously deprecated in release 2015f.
53 (Thanks to Tim Parenti.)
55 zic now defaults to '-b slim' instead of to '-b fat'.
57 zic's new '-l -' and '-p -' options uninstall any existing
58 localtime and posixrules files, respectively.
60 The undocumented and ineffective tzsetwall function has been
63 Changes to build procedure
65 The Makefile now defaults POSIXRULES to '-', so the posixrules
66 feature (obsolete as of 2019b) is no longer installed by default.
68 Changes to documentation and commentary
70 The long-obsolete files pacificnew, systemv, and yearistype.sh have
71 been removed from the distribution. (Thanks to Tim Parenti.)
74 Release 2020a - 2020-04-23 16:03:47 -0700
77 Morocco springs forward on 2020-05-31, not 2020-05-24.
78 Canada's Yukon advanced to -07 year-round on 2020-03-08.
79 America/Nuuk renamed from America/Godthab.
80 zic now supports expiration dates for leap second lists.
82 Changes to future timestamps
84 Morocco's second spring-forward transition in 2020 will be May 31,
85 not May 24 as predicted earlier. (Thanks to Semlali Naoufal.)
86 Adjust future-year predictions to use the first Sunday after the
87 day after Ramadan, not the first Sunday after Ramadan.
89 Canada's Yukon, represented by America/Whitehorse and
90 America/Dawson, advanced to -07 year-round, beginning with its
91 spring-forward transition on 2020-03-08, and will not fall back on
92 2020-11-01. Although a government press release calls this
93 "permanent Pacific Daylight Saving Time", we prefer MST for
94 consistency with nearby Dawson Creek, Creston, and Fort Nelson.
95 (Thanks to Tim Parenti.)
97 Changes to past timestamps
99 Shanghai observed DST in 1919. (Thanks to Phake Nick.)
101 Changes to timezone identifiers
103 To reflect current usage in English better, America/Godthab has
104 been renamed to America/Nuuk. A backwards-compatibility link
105 remains for the old name.
109 localtime.c no longer mishandles timestamps after the last
110 transition in a TZif file with leap seconds and with daylight
111 saving time transitions projected into the indefinite future.
112 For example, with TZ='America/Los_Angeles' with leap seconds,
113 zdump formerly reported a DST transition on 2038-03-14
114 from 01:59:32.999... to 02:59:33 instead of the correct transition
115 from 01:59:59.999... to 03:00:00.
117 zic -L now supports an Expires line in the leapseconds file, and
118 truncates the TZif output accordingly. This propagates leap
119 second expiration information into the TZif file, and avoids the
120 abovementioned localtime.c bug as well as similar bugs present in
121 many client implementations. If no Expires line is present, zic
122 -L instead truncates the TZif output based on the #expires comment
123 present in leapseconds files distributed by tzdb 2018f and later;
124 however, this usage is obsolescent. For now, the distributed
125 leapseconds file has an Expires line that is commented out, so
126 that the file can be fed to older versions of zic which ignore the
127 commented-out line. Future tzdb distributions are planned to
128 contain a leapseconds file with an Expires line.
130 The configuration macros HAVE_TZNAME and USG_COMPAT should now be
131 set to 1 if the system library supports the feature, and 2 if not.
132 As before, these macros are nonzero if tzcode should support the
133 feature, zero otherwise.
135 The configuration macro ALTZONE now has the same values with the
136 same meaning as HAVE_TZNAME and USG_COMPAT.
138 The code's defense against CRLF in leap-seconds.list is now
139 portable to POSIX awk. (Problem reported by Deborah Goldsmith.)
141 Although the undocumented tzsetwall function is not changed in
142 this release, it is now deprecated in preparation for removal in
143 future releases. Due to POSIX requirements, tzsetwall has not
144 worked for some time. Any code that uses it should instead use
145 tzalloc(NULL) or, if portability trumps thread-safety, should
146 unset the TZ environment variable.
148 Changes to commentary
150 The Îles-de-la-Madeleine and the Listuguj reserve are noted as
151 following America/Halifax, and comments about Yukon's "south" and
152 "north" have been corrected to say "east" and "west". (Thanks to
156 Release 2019c - 2019-09-11 08:59:48 -0700
159 Fiji observes DST from 2019-11-10 to 2020-01-12.
160 Norfolk Island starts observing Australian-style DST.
162 Changes to future timestamps
164 Fiji's next DST transitions will be 2019-11-10 and 2020-01-12
165 instead of 2019-11-03 and 2020-01-19. (Thanks to Raymond Kumar.)
166 Adjust future guesses accordingly.
168 Norfolk Island will observe Australian-style DST starting in
169 spring 2019. The first transition is on 2019-10-06. (Thanks to
170 Kyle Czech and Michael Deckers.)
172 Changes to past timestamps
174 Many corrections to time in Turkey from 1940 through 1985.
175 (Thanks to Oya Vulaş via Alois Treindl, and to Kıvanç Yazan.)
177 The Norfolk Island 1975-03-02 transition was at 02:00 standard
178 time, not 02:00 DST. (Thanks to Michael Deckers.)
180 South Korea observed DST from 1948 through 1951. Although this
181 info was supposed to appear in release 2014j, a typo inadvertently
182 suppressed the change. (Thanks to Alois Treindl.)
184 Detroit observed DST in 1967 and 1968 following the US DST rules,
185 except that its 1967 DST began on June 14 at 00:01. (Thanks to
186 Alois Treindl for pointing out that the old data entries were
189 Fix several errors in pre-1970 transitions in Perry County, IN.
190 (Thanks to Alois Triendl for pointing out the 1967/9 errors.)
192 Edmonton did not observe DST in 1967 or 1969. In 1946 Vancouver
193 ended DST on 09-29 not 10-13, and Vienna ended DST on 10-07 not
194 10-06. In 1945 Königsberg (now Kaliningrad) switched from +01/+02
195 to +02/+03 on 04-10 not 01-01, and its +02/+03 is abbreviated
196 EET/EEST, not CET/CEST. (Thanks to Alois Triendl.) In 1946
197 Königsberg switched to +03 on 04-07 not 01-01.
199 In 1946 Louisville switched from CST to CDT on 04-28 at 00:01, not
200 01-01 at 00:00. (Thanks to Alois Treindl and Michael Deckers.)
201 Also, it switched from CST to CDT on 1950-04-30, not 1947-04-27.
203 The 1892-05-01 transition in Brussels was at 00:17:30, not at noon.
204 (Thanks to Michael Deckers.)
206 Changes to past time zone abbreviations and DST flags
208 Hong Kong Winter Time, observed from 1941-10-01 to 1941-12-25,
209 is now flagged as DST and is abbreviated HKWT not HKT.
213 leapseconds.awk now relies only on its input data, rather than
214 also relying on its comments. (Inspired by code from Dennis
215 Ferguson and Chris Woodbury.)
217 The code now defends against CRLFs in leap-seconds.list.
218 (Thanks to Brian Inglis and Chris Woodbury.)
220 Changes to documentation and commentary
222 theory.html discusses leap seconds. (Thanks to Steve Summit.)
224 Nashville's newspapers dueled about the time of day in the 1950s.
225 (Thanks to John Seigenthaler.)
227 Liechtenstein observed Swiss DST in 1941/2.
228 (Thanks to Alois Treindl.)
231 Release 2019b - 2019-07-01 00:09:53 -0700
234 Brazil no longer observes DST.
235 'zic -b slim' outputs smaller TZif files; please try it out.
236 Palestine's 2019 spring-forward transition was on 03-29, not 03-30.
238 Changes to future timestamps
240 Brazil has canceled DST and will stay on standard time indefinitely.
241 (Thanks to Steffen Thorsen, Marcus Diniz, and Daniel Soares de
244 Predictions for Morocco now go through 2087 instead of 2037, to
245 work around a problem on newlib when using TZif files output by
246 zic 2019a or earlier. (Problem reported by David Gauchard.)
248 Changes to past and future timestamps
250 Palestine's 2019 spring transition was 03-29 at 00:00, not 03-30
251 at 01:00. (Thanks to Sharef Mustafa and Even Scharning.) Guess
252 future transitions to be March's last Friday at 00:00.
254 Changes to past timestamps
256 Hong Kong's 1941-06-15 spring-forward transition was at 03:00, not
257 03:30. Its 1945 transition from JST to HKT was on 11-18 at 02:00,
258 not 09-15 at 00:00. In 1946 its spring-forward transition was on
259 04-21 at 00:00, not the previous day at 03:30. From 1946 through
260 1952 its fall-back transitions occurred at 04:30, not at 03:30.
261 In 1947 its fall-back transition was on 11-30, not 12-30.
264 Changes to past time zone abbreviations
266 Italy's 1866 transition to Rome Mean Time was on December 12, not
267 September 22. This affects only the time zone abbreviation for
268 Europe/Rome between those dates. (Thanks to Stephen Trainor and
271 Changes affecting metadata only
273 Add info about the Crimea situation in zone1970.tab and zone.tab.
274 (Problem reported by Serhii Demediuk.)
278 zic's new -b option supports a way to control data bloat and to
279 test for year-2038 bugs in software that reads TZif files.
280 'zic -b fat' and 'zic -b slim' generate larger and smaller output;
281 for example, changing from fat to slim shrinks the Europe/London
282 file from 3648 to 1599 bytes, saving about 56%. Fat and slim
283 files represent the same set of timestamps and use the same TZif
284 format as documented in tzfile(5) and in Internet RFC 8536.
285 Fat format attempts to work around bugs or incompatibilities in
286 older software, notably software that mishandles 64-bit TZif data
287 or uses obsolete TZ strings like "EET-2EEST" that lack DST rules.
288 Slim format is more efficient and does not work around 64-bit bugs
289 or obsolete TZ strings. Currently zic defaults to fat format
290 unless you compile with -DZIC_BLOAT_DEFAULT=\"slim\"; this
291 out-of-the-box default is intended to change in future releases
292 as the buggy software often mishandles timestamps anyway.
294 zic no longer treats a set of rules ending in 2037 specially.
295 Previously, zic assumed that such a ruleset meant that future
296 timestamps could not be predicted, and therefore omitted a
297 POSIX-like TZ string in the TZif output. The old behavior is no
298 longer needed for current tzdata, and caused problems with newlib
299 when used with older tzdata (reported by David Gauchard).
301 zic no longer generates some artifact transitions. For example,
302 Europe/London no longer has a no-op transition in January 1996.
304 Changes to build procedure
306 tzdata.zi now assumes zic 2017c or later. This shrinks tzdata.zi
309 Changes to documentation and commentary
311 The Makefile now documents the POSIXRULES macro as being obsolete,
312 and similarly, zic's -p POSIXRULES option is now documented as
313 being obsolete. Although the POSIXRULES feature still exists and
314 works as before, in practice it is rarely used for its intended
315 purpose, and it does not work either in the default reference
316 implementation (for timestamps after 2037) or in common
317 implementations such as GNU/Linux (for contemporary timestamps).
318 Since POSIXRULES was designed primarily as a temporary transition
319 facility for System V platforms that died off decades ago, it is
320 being decommissioned rather than institutionalized.
322 New info on Bonin Islands and Marcus (thanks to Wakaba and Phake Nick).
325 Release 2019a - 2019-03-25 22:01:33 -0700
328 Palestine "springs forward" on 2019-03-30 instead of 2019-03-23.
329 Metlakatla "fell back" to rejoin Alaska Time on 2019-01-20 at 02:00.
331 Changes to past and future timestamps
333 Palestine will not start DST until 2019-03-30, instead of 2019-03-23 as
334 previously predicted. Adjust our prediction by guessing that spring
335 transitions will be between 24 and 30 March, which matches recent practice
336 since 2016. (Thanks to Even Scharning and Tim Parenti.)
338 Metlakatla ended its observance of Pacific standard time,
339 rejoining Alaska Time, on 2019-01-20 at 02:00. (Thanks to Ryan
340 Stanley and Tim Parenti.)
342 Changes to past timestamps
344 Israel observed DST in 1980 (08-02/09-13) and 1984 (05-05/08-25).
345 (Thanks to Alois Treindl and Isaac Starkman.)
347 Changes to time zone abbreviations
349 Etc/UCT is now a backward-compatibility link to Etc/UTC, instead
350 of being a separate zone that generates the abbreviation "UCT",
351 which nowadays is typically a typo. (Problem reported by Isiah
356 zic now has an -r option to limit the time range of output data.
357 For example, 'zic -r @1000000000' limits the output data to
358 timestamps starting 1000000000 seconds after the Epoch.
359 This helps shrink output size and can be useful for applications
360 not needing the full timestamp history, such as TZDIST truncation;
361 see Internet RFC 8536 section 5.1. (Inspired by a feature request
362 from Christopher Wong, helped along by bug reports from Wong and
365 Changes to documentation
367 Mention Internet RFC 8536 (February 2019), which documents TZif.
369 tz-link.html now cites tzdata-meta
370 <https://tzdata-meta.timtimeonline.com/>.
373 Release 2018i - 2018-12-30 11:05:43 -0800
376 São Tomé and Príncipe switches from +01 to +00 on 2019-01-01.
378 Changes to future timestamps
380 Due to a change in government, São Tomé and Príncipe switches back
381 from +01 to +00 on 2019-01-01 at 02:00. (Thanks to Vadim
382 Nasardinov and Michael Deckers.)
385 Release 2018h - 2018-12-23 17:59:32 -0800
388 Qyzylorda, Kazakhstan moved from +06 to +05 on 2018-12-21.
389 New zone Asia/Qostanay because Qostanay, Kazakhstan didn't move.
390 Metlakatla, Alaska observes PST this winter only.
391 Guess Morocco will continue to adjust clocks around Ramadan.
392 Add predictions for Iran from 2038 through 2090.
394 Changes to future timestamps
396 Guess that Morocco will continue to fall back just before and
397 spring forward just after Ramadan, the practice since 2012.
398 (Thanks to Maamar Abdelkader.) This means Morocco will observe
399 negative DST during Ramadan in main and vanguard formats, and in
400 rearguard format it stays in the +00 timezone and observes
401 ordinary DST in all months other than Ramadan. As before, extend
402 this guesswork to the year 2037. As a consequence, Morocco is
403 scheduled to observe three DST transitions in some Gregorian years
404 (e.g., 2033) due to the mismatch between the Gregorian and Islamic
407 The table of exact transitions for Iranian DST has been extended.
408 It formerly cut off before the year 2038 in a nod to 32-bit time_t.
409 It now cuts off before 2091 as there is doubt about how the Persian
410 calendar will treat 2091. This change predicts DST transitions in
411 2038-9, 2042-3, and 2046-7 to occur one day later than previously
412 predicted. As before, post-cutoff transitions are approximated.
414 Changes to past and future timestamps
416 Qyzylorda (aka Kyzylorda) oblast in Kazakhstan moved from +06 to
417 +05 on 2018-12-21. This is a zone split as Qostanay (aka
418 Kostanay) did not switch, so create a zone Asia/Qostanay.
420 Metlakatla moved from Alaska to Pacific standard time on 2018-11-04.
421 It did not change clocks that day and remains on -08 this winter.
422 (Thanks to Ryan Stanley.) It will revert to the usual Alaska
423 rules next spring, so this change affects only timestamps
424 from 2018-11-04 through 2019-03-10.
426 Change to past timestamps
428 Kwajalein's 1993-08-20 transition from -12 to +12 was at 24:00,
429 not 00:00. I transcribed the time incorrectly from Shanks.
430 (Thanks to Phake Nick.)
432 Nauru's 1979 transition was on 02-10 at 02:00, not 05-01 at 00:00.
433 (Thanks to Phake Nick.)
435 Guam observed DST irregularly from 1959 through 1977.
436 (Thanks to Phake Nick.)
438 Hong Kong observed DST in 1941 starting 06-15 (not 04-01), then on
439 10-01 changed standard time to +08:30 (not +08). Its transition
440 back to +08 after WWII was on 1945-09-15, not the previous day.
441 Its 1904-10-30 change took effect at 01:00 +08 (not 00:00 LMT).
442 (Thanks to Phake Nick, Steve Allen, and Joseph Myers.) Also,
443 its 1952 fallback was on 11-02 (not 10-25).
445 This release contains many changes to timestamps before 1946 due
446 to Japanese possession or occupation of Pacific/Chuuk,
447 Pacific/Guam, Pacific/Kosrae, Pacific/Kwajalein, Pacific/Majuro,
448 Pacific/Nauru, Pacific/Palau, and Pacific/Pohnpei.
449 (Thanks to Phake Nick.)
451 Assume that the Spanish East Indies was like the Philippines and
452 observed American time until the end of 1844. This affects
453 Pacific/Chuuk, Pacific/Kosrae, Pacific/Palau, and Pacific/Pohnpei.
455 Changes to past tm_isdst flags
457 For the recent Morocco change, the tm_isdst flag should be 1 from
458 2018-10-27 00:00 to 2018-10-28 03:00. (Thanks to Michael Deckers.)
459 Give a URL to the official decree. (Thanks to Matt Johnson.)
462 Release 2018g - 2018-10-26 22:22:45 -0700
465 Morocco switches to permanent +01 on 2018-10-28.
467 Changes to future timestamps
469 Morocco switches from +00/+01 to permanent +01 effective 2018-10-28,
470 so its clocks will not fall back as previously scheduled.
471 (Thanks to Mohamed Essedik Najd and Brian Inglis.)
475 When generating TZif files with leap seconds, zic no longer uses a
476 format that trips up older 32-bit clients, fixing a bug introduced
477 in 2018f. (Reported by Daniel Fischer.) Also, the zic workaround
478 for QTBUG-53071 now also works for TZif files with leap seconds.
480 The translator to rearguard format now rewrites the line
481 "Rule Japan 1948 1951 - Sep Sat>=8 25:00 0 S" to
482 "Rule Japan 1948 1951 - Sep Sun>=9 1:00 0 S".
483 This caters to zic before 2007 and to Oracle TZUpdater 2.2.0
484 and earlier. (Reported by Christos Zoulas.)
486 Changes to past time zone abbreviations
488 Change HDT to HWT/HPT for WWII-era abbreviations in Hawaii.
489 This reverts to 2011h, as the abbreviation change in 2011i was
492 Changes to documentation
494 tzfile.5 has new sections on interoperability issues.
497 Release 2018f - 2018-10-18 00:14:18 -0700
500 Volgograd moves from +03 to +04 on 2018-10-28.
501 Fiji ends DST 2019-01-13, not 2019-01-20.
502 Most of Chile changes DST dates, effective 2019-04-06.
504 Changes to future timestamps
506 Volgograd moves from +03 to +04 on 2018-10-28 at 02:00.
507 (Thanks to Alexander Fetisov and Stepan Golosunov.)
509 Fiji ends DST 2019-01-13 instead of the 2019-01-20 previously
510 predicted. (Thanks to Raymond Kumar.) Adjust future predictions
513 Most of Chile will end DST on the first Saturday in April at 24:00 mainland
514 time, and resume DST on the first Saturday in September at 24:00 mainland
515 time. The changes are effective from 2019-04-06, and do not affect the
516 Magallanes region modeled by America/Punta_Arenas. (Thanks to Juan Correa
517 and Tim Parenti.) Adjust future predictions accordingly.
519 Changes to past timestamps
521 The 2018-05-05 North Korea 30-minute time zone change took place
522 at 23:30 the previous day, not at 00:00 that day.
524 China's 1988 spring-forward transition was on April 17, not
525 April 10. Its DST transitions in 1986/91 were at 02:00, not 00:00.
528 Fix several issues for Macau before 1992. Macau's pre-1904 LMT
529 was off by 10 s. Macau switched to +08 in 1904 not 1912, and
530 temporarily switched to +09/+10 during World War II. Macau
531 observed DST in 1942/79, not 1961/80, and there were several
532 errors for transition times and dates. (Thanks to P Chan.)
534 The 1948-1951 fallback transitions in Japan were at 25:00 on
535 September's second Saturday, not at 24:00. (Thanks to Phake Nick.)
536 zic turns this into 01:00 on the day after September's second
537 Saturday, which is the best that POSIX or C platforms can do.
539 Incorporate 1940-1949 Asia/Shanghai DST transitions from a 2014
540 paper by Li Yu, replacing more-questionable data from Shanks.
542 Changes to time zone abbreviations
544 Use "PST" and "PDT" for Philippine time. (Thanks to Paul Goyette.)
548 zic now always generates TZif files where time type 0 is used for
549 timestamps before the first transition. This simplifies the
550 reading of TZif files and should not affect behavior of existing
551 TZif readers because the same set of time types is used; only
552 their internal indexes may have changed. This affects only the
553 legacy zones EST5EDT, CST6CDT, MST7MDT, PST8PDT, CET, MET, and
554 EET, which previously used nonzero types for these timestamps.
556 Because of the type 0 change, zic no longer outputs a dummy
557 transition at time -2**59 (before the Big Bang), as clients should
558 no longer need this to handle historical timestamps correctly.
559 This reverts a change introduced in 2013d and shrinks most TZif
560 files by a few bytes.
562 zic now supports negative time-of-day in Rule and Leap lines, e.g.,
563 "Rule X min max - Apr lastSun -6:00 1:00 -" means the transition
564 occurs at 18:00 on the Saturday before the last Sunday in April.
565 This behavior was documented in 2018a but the code did not
566 entirely match the documentation.
568 localtime.c no longer requires at least one time type in TZif
569 files that lack transitions or have a POSIX-style TZ string. This
570 future-proofs the code against possible future extensions to the
571 format that would allow TZif files with POSIX-style TZ strings and
572 without transitions or time types.
574 A read-access subscript error in localtime.c has been fixed.
575 It could occur only in TZif files with timecnt == 0, something that
576 does not happen in practice now but could happen in future versions.
578 localtime.c no longer ignores TZif POSIX-style TZ strings that
579 specify only standard time. Instead, these TZ strings now
580 override the default time type for timestamps after the last
581 transition (or for all timestamps if there are no transitions),
582 just as DST strings specifying DST have always done.
584 leapseconds.awk now outputs "#updated" and "#expires" comments,
585 and supports leap seconds at the ends of months other than June
586 and December. (Inspired by suggestions from Chris Woodbury.)
588 Changes to documentation
590 New restrictions: A Rule name must start with a character that
591 is neither an ASCII digit nor "-" nor "+", and an unquoted name
592 should not use characters in the set "!$%&'()*,/:;<=>?@[\]^`{|}~".
593 The latter restriction makes room for future extensions (a
594 possibility noted by Tom Lane).
596 tzfile.5 now documents what time types apply before the first and
597 after the last transition, if any.
599 Documentation now uses the spelling "timezone" for a TZ setting
600 that determines timestamp history, and "time zone" for a
601 geographic region currently sharing the same standard time.
603 The name "TZif" is now used for the tz binary data format.
605 tz-link.htm now mentions the A0 TimeZone Migration utilities.
606 (Thanks to Aldrin Martoq for the link.)
608 Changes to build procedure
610 New 'make' target 'rearguard_tarballs' to build the rearguard
611 tarball only. This is a convenience on platforms that lack lzip
612 if you want to build the rearguard tarball. (Problem reported by
615 tzdata.zi is now more stable from release to release. (Problem
616 noted by Tom Lane.) It is also a bit shorter.
618 tzdata.zi now can contain comment lines documenting configuration
619 information, such as which data format was selected, which input
620 files were used, and how leap seconds are treated. (Problems
621 noted by Lester Caine and Brian Inglis.) If the Makefile defaults
622 are used these comment lines are absent, for backward
623 compatibility. A redistributor intending to alter its copy of the
624 files should also append "-LABEL" to the 'version' file's first
625 line, where "LABEL" identifies the redistributor's change.
628 Release 2018e - 2018-05-01 23:42:51 -0700
632 North Korea switches back to +09 on 2018-05-05.
633 The main format uses negative DST again, for Ireland etc.
634 'make tarballs' now also builds a rearguard tarball.
635 New 's' and 'd' suffixes in SAVE columns of Rule and Zone lines.
637 Changes to past and future timestamps
639 North Korea switches back from +0830 to +09 on 2018-05-05.
640 (Thanks to Kang Seonghoon, Arthur David Olson, Seo Sanghyeon,
643 Bring back the negative-DST changes of 2018a, except be more
644 compatible with data parsers that do not support negative DST.
645 Also, this now affects historical timestamps in Namibia and the
646 former Czechoslovakia, not just Ireland. The main format now uses
647 negative DST to model timestamps in Europe/Dublin (from 1971 on),
648 Europe/Prague (1946/7), and Africa/Windhoek (1994/2017). This
649 does not affect UT offsets, only time zone abbreviations and the
650 tm_isdst flag. Also, this does not affect rearguard or vanguard
651 formats; effectively the main format now uses vanguard instead of
652 rearguard format. Data parsers that do not support negative DST
653 can still use data from the rearguard tarball described below.
655 Changes to build procedure
657 The command 'make tarballs' now also builds the tarball
658 tzdataVERSION-rearguard.tar.gz, which is like tzdataVERSION.tar.gz
659 except that it uses rearguard format intended for trailing-edge
662 Changes to data format and to code
664 The SAVE column of Rule and Zone lines can now have an 's' or 'd'
665 suffix, which specifies whether the adjusted time is standard time
666 or daylight saving time. If no suffix is given, daylight saving
667 time is used if and only if the SAVE column is nonzero; this is
668 the longstanding behavior. Although this new feature is not used
669 in tzdata, it could be used to specify the legal time in Namibia
670 1994-2017, as opposed to the popular time (see below).
672 Changes to past timestamps
674 From 1994 through 2017 Namibia observed DST in winter, not summer.
675 That is, it used negative DST, as Ireland still does. This change
676 does not affect UTC offsets; it affects only the tm_isdst flag and
677 the abbreviation used during summer, which is now CAT, not WAST.
678 Although (as noted by Michael Deckers) summer and winter time were
679 both simply called "standard time" in Namibian law, in common
680 practice winter time was considered to be DST (as noted by Stephen
681 Colebourne). The full effect of this change is only in vanguard
682 and main format; in rearguard format, the tm_isdst flag is still
683 zero in winter and nonzero in summer.
685 In 1946/7 Czechoslovakia also observed negative DST in winter.
686 The full effect of this change is only in vanguard and main
687 formats; in rearguard format, it is modeled as plain GMT without
688 daylight saving. Also, the dates of some 1944/5 DST transitions
689 in Czechoslovakia have been changed.
692 Release 2018d - 2018-03-22 07:05:46 -0700
696 Palestine starts DST a week earlier in 2018.
697 Add support for vanguard and rearguard data consumers.
698 Add subsecond precision to source data format, though not to data.
700 Changes to future timestamps
702 In 2018, Palestine starts DST on March 24, not March 31.
703 Adjust future predictions accordingly. (Thanks to Sharef Mustafa.)
705 Changes to past and future timestamps
707 Casey Station in Antarctica changed from +11 to +08 on 2018-03-11
708 at 04:00. (Thanks to Steffen Thorsen.)
710 Changes to past timestamps
712 Historical transitions for Uruguay, represented by
713 America/Montevideo, have been updated per official legal documents,
714 replacing previous data mainly originating from the inventions of
715 Shanks & Pottenger. This has resulted in adjustments ranging from
716 30 to 90 minutes in either direction over at least two dozen
717 distinct periods ranging from one day to several years in length.
718 A mere handful of pre-1991 transitions are unaffected; data since
719 then has come from more reliable contemporaneous reporting. These
720 changes affect various timestamps in 1920-1923, 1936, 1939,
721 1942-1943, 1959, 1966-1970, 1972, 1974-1980, and 1988-1990.
722 Additionally, Uruguay's pre-standard-time UT offset has been
723 adjusted westward by 7 seconds, from UT-03:44:44 to UT-03:44:51, to
724 match the location of the Observatory of the National Meteorological
725 Institute in Montevideo.
726 (Thanks to Jeremie Bonjour, Tim Parenti, and Michael Deckers.)
728 Enderbury and Kiritimati skipped New Year's Eve 1994, not
729 New Year's Day 1995. (Thanks to Kerry Shetline.)
731 Fix the 1912-01-01 transition for Portugal and its colonies.
732 This transition was at 00:00 according to the new UT offset, not
733 according to the old one. Also assume that Cape Verde switched on
734 the same date as the rest, not in 1907. This affects
735 Africa/Bissau, Africa/Sao_Tome, Asia/Macau, Atlantic/Azores,
736 Atlantic/Cape_Verde, Atlantic/Madeira, and Europe/Lisbon.
737 (Thanks to Michael Deckers.)
739 Fix an off-by-1 error for pre-1913 timestamps in Jamaica and in
742 Changes to past time zone abbreviations
744 MMT took effect in Uruguay from 1908-06-10, not 1898-06-28. There
745 is no clock change associated with the transition.
747 Changes to build procedure
749 The new DATAFORM macro in the Makefile lets the installer choose
750 among three source data formats. The idea is to lessen downstream
751 disruption when data formats are improved.
753 * DATAFORM=vanguard installs from the latest, bleeding-edge
754 format. DATAFORM=main (the default) installs from the format
755 used in the 'africa' etc. files. DATAFORM=rearguard installs
756 from a trailing-edge format. Eventually, elements of today's
757 vanguard format should move to the main format, and similarly
758 the main format's features should eventually move to the
761 * In the current version, the main and rearguard formats are
762 identical and match that of 2018c, so this change does not
763 affect default behavior. The vanguard format currently contains
764 one feature not in the main format: negative SAVE values. This
765 improves support for Ireland, which uses Irish Standard Time
766 (IST, UTC+01) in summer and GMT (UTC) in winter. tzcode has
767 supported negative SAVE values for decades, and this feature
768 should move to the main format soon. However, it will not move
769 to the rearguard format for quite some time because some
770 downstream parsers do not support it.
772 * The build procedure constructs three files vanguard.zi, main.zi,
773 and rearguard.zi, one for each format. Although the files
774 represent essentially the same data, they may have minor
775 discrepancies that users are not likely to notice. The files
776 are intended for downstream data consumers and are not
777 installed. Zoneinfo parsers that do not support negative SAVE values
778 should start using rearguard.zi, so that they will be unaffected
779 when the negative-DST feature moves from vanguard to main.
780 Bleeding-edge Zoneinfo parsers that support the new features
781 already can use vanguard.zi; in this respect, current tzcode is
784 The Makefile should now be safe for parallelized builds, and 'make
785 -j to2050new.tzs' is now much faster on a multiprocessor host
788 When built with -DSUPPRESS_TZDIR, the tzcode library no longer
789 prepends TZDIR/ to file names that do not begin with '/'. This is
790 not recommended for general use, due to its security implications.
791 (From a suggestion by Manuela Friedrich.)
795 zic now accepts subsecond precision in expressions like
796 00:19:32.13, which is approximately the legal time of the
797 Netherlands from 1835 to 1937. However, because it is
798 questionable whether the few recorded uses of non-integer offsets
799 had subsecond precision in practice, there are no plans for tzdata
800 to use this feature. (Thanks to Steve Allen for pointing out
801 the limitations of historical data in this area.)
803 The code is a bit more portable to MS-Windows. Installers can
804 compile with -DRESERVE_STD_EXT_IDS on MS-Windows platforms that
805 reserve identifiers like 'localtime'. (Thanks to Manuela
808 Changes to documentation and commentary
810 theory.html now outlines tzdb's extensions to POSIX's model for
811 civil time, and has a section "POSIX features no longer needed"
812 that lists POSIX API components that are now vestigial.
813 (From suggestions by Steve Summit.) It also better distinguishes
814 time zones from tz regions. (From a suggestion by Guy Harris.)
816 Commentary is now more consistent about using the phrase "daylight
817 saving time", to match the C name tm_isdst. Daylight saving time
818 need not occur in summer, and need not have a positive offset from
821 Commentary about historical transitions in Uruguay has been expanded
822 with links to many relevant legal documents.
823 (Thanks to Tim Parenti.)
825 Commentary now uses some non-ASCII characters with Unicode value
826 less than U+0100, as they can be useful and should work even with
827 older editors such as XEmacs.
830 Release 2018c - 2018-01-22 23:00:44 -0800
833 Revert Irish changes that relied on negative SAVE values.
837 Revert the 2018a change to Europe/Dublin. As before, this change
838 does not affect UT offsets or abbreviations; it affects only
839 whether timestamps are considered to be standard time or
840 daylight-saving time, as expressed in the tm_isdst flag of C's
841 struct tm type. This reversion is intended to be a temporary
842 workaround for problems discovered with downstream uses of
843 releases 2018a and 2018b, which implemented Irish time by using
844 negative SAVE values in the Eire rules of the 'europe' file.
845 Although negative SAVE values have been part of tzcode for many
846 years and are supported by many platforms, they were not
847 documented before 2018a and ICU and OpenJDK do not currently
848 support them. A mechanism to export data to platforms lacking
849 support for negative DST is planned to be developed before the
850 change is reapplied. (Problems reported by Deborah Goldsmith and
853 Changes to past timestamps
855 Japanese DST transitions (1948-1951) were Sundays at 00:00, not
856 Saturdays or Sundays at 02:00. (Thanks to Takayuki Nikai.)
858 Changes to build procedure
860 The build procedure now works around mawk 1.3.3's lack of support
861 for character class expressions. (Problem reported by Ohyama.)
864 Release 2018b - 2018-01-17 23:24:48 -0800
867 Fix a packaging problem in tz2018a, which was missing 'pacificnew'.
869 Changes to build procedure
871 The distribution now contains the file 'pacificnew' again.
872 This file was inadvertantly omitted in the 2018a distribution.
873 (Problem reported by Matias Fonzo.)
876 Release 2018a - 2018-01-12 22:29:21 -0800
879 São Tomé and Príncipe switched from +00 to +01.
880 Brazil's DST will now start on November's first Sunday.
881 Ireland's standard time is now in the summer, not the winter.
882 Use Debian-style installation locations, instead of 4.3BSD-style.
885 Changes to past and future timestamps
887 São Tomé and Príncipe switched from +00 to +01 on 2018-01-01 at
888 01:00. (Thanks to Steffen Thorsen and Michael Deckers.)
890 Changes to future timestamps
892 Starting in 2018 southern Brazil will begin DST on November's
893 first Sunday instead of October's third Sunday. (Thanks to
896 Changes to past timestamps
898 A discrepancy of 4 s in timestamps before 1931 in South Sudan has
899 been corrected. The 'backzone' and 'zone.tab' files did not agree
900 with the 'africa' and 'zone1970.tab' files. (Problem reported by
903 The abbreviation invented for Bolivia Summer Time (1931-2) is now
904 BST instead of BOST, to be more consistent with the convention
905 used for Latvian Summer Time (1918-9) and for British Summer Time.
909 Change Europe/Dublin so that it observes Irish Standard Time (UT
910 +01) in summer and GMT (as negative daylight-saving) in winter,
911 instead of observing standard time (GMT) in winter and Irish
912 Summer Time (UT +01) in summer. This change does not affect UT
913 offsets or abbreviations; it affects only whether timestamps are
914 considered to be standard time or daylight-saving time, as
915 expressed in the tm_isdst flag of C's struct tm type.
916 (Discrepancy noted by Derick Rethans.)
918 Changes to build procedure
920 The default installation locations have been changed to mostly
921 match Debian circa 2017, instead of being designed as an add-on to
922 4.3BSD circa 1986. This affects the Makefile macros TOPDIR,
923 TZDIR, MANDIR, and LIBDIR. New Makefile macros TZDEFAULT, USRDIR,
924 USRSHAREDIR, BINDIR, ZDUMPDIR, and ZICDIR let installers tailor
925 locations more precisely. (This responds to suggestions from
926 Brian Inglis and from Steve Summit.)
928 The default installation procedure no longer creates the
929 backward-compatibility link US/Pacific-New, which causes
930 confusion during user setup (e.g., see Debian bug 815200).
931 Use 'make BACKWARD="backward pacificnew"' to create the link
932 anyway, for now. Eventually we plan to remove the link entirely.
934 tzdata.zi now contains a version-number comment.
935 (Suggested by Tom Lane.)
937 The Makefile now quotes values like BACKWARD more carefully when
938 passing them to the shell. (Problem reported by Zefram.)
940 Builders no longer need to specify -DHAVE_SNPRINTF on platforms
941 that have snprintf and use pre-C99 compilers. (Problem reported
946 zic has a new option -t FILE that specifies the location of the
947 file that determines local time when TZ is unset. The default for
948 this location can be configured via the new TZDEFAULT makefile
949 macro, which defaults to /etc/localtime.
951 Diagnostics and commentary now distinguish UT from UTC more
952 carefully; see theory.html for more information about UT vs UTC.
954 zic has been ported to GCC 8's -Wstringop-truncation option.
955 (Problem reported by Martin Sebor.)
957 Changes to documentation and commentary
959 The zic man page now documents the longstanding behavior that
960 times and years can be out of the usual range, with negative times
961 counting backwards from midnight and with year 0 preceding year 1.
962 (Problem reported by Michael Deckers.)
964 The theory.html file now mentions the POSIX limit of six chars
965 per abbreviation, and lists alphabetic abbreviations used.
967 The files tz-art.htm and tz-link.htm have been renamed to
968 tz-art.html and tz-link.html, respectively, for consistency with
969 other file names and to simplify web server configuration.
972 Release 2017c - 2017-10-20 14:49:34 -0700
975 Northern Cyprus switches from +03 to +02/+03 on 2017-10-29.
976 Fiji ends DST 2018-01-14, not 2018-01-21.
977 Namibia switches from +01/+02 to +02 on 2018-04-01.
978 Sudan switches from +03 to +02 on 2017-11-01.
979 Tonga likely switches from +13/+14 to +13 on 2017-11-05.
980 Turks & Caicos switches from -04 to -05/-04 on 2018-11-04.
981 A new file tzdata.zi now holds a small text copy of all data.
982 The zic input format has been regularized slightly.
984 Changes to future timestamps
986 Northern Cyprus has decided to resume EU rules starting
987 2017-10-29, thus reinstituting winter time.
989 Fiji ends DST 2018-01-14 instead of the 2018-01-21 previously
990 predicted. (Thanks to Dominic Fok.) Adjust future predictions
993 Namibia will switch from +01 with DST to +02 all year on
994 2017-09-03 at 02:00. This affects UT offsets starting 2018-04-01
995 at 02:00. (Thanks to Steffen Thorsen.)
997 Sudan will switch from +03 to +02 on 2017-11-01. (Thanks to Ahmed
998 Atyya and Yahia Abdalla.) South Sudan is not switching, so
999 Africa/Juba is no longer a link to Africa/Khartoum.
1001 Tonga has likely ended its experiment with DST, and will not
1002 adjust its clocks on 2017-11-05. Although Tonga has not announced
1003 whether it will continue to observe DST, the IATA is assuming that
1004 it will not. (Thanks to David Wade.)
1006 Turks & Caicos will switch from -04 all year to -05 with US DST on
1007 2018-03-11 at 03:00. This affects UT offsets starting 2018-11-04
1008 at 02:00. (Thanks to Steffen Thorsen.)
1010 Changes to past timestamps
1012 Namibia switched from +02 to +01 on 1994-03-21, not 1994-04-03.
1013 (Thanks to Arthur David Olson.)
1015 Detroit did not observe DST in 1967.
1017 Use railway time for Asia/Kolkata before 1941, by switching to
1018 Madras local time (UT +052110) in 1870, then to IST (UT +0530) in
1019 1906. Also, treat 1941-2's +0630 as DST, like 1942-5.
1021 Europe/Dublin's 1946 and 1947 fallback transitions occurred at
1022 02:00 standard time, not 02:00 DST. (Thanks to Michael Deckers.)
1024 Pacific/Apia and Pacific/Pago_Pago switched from Antipodean to
1025 American time in 1892, not 1879. (Thanks to Michael Deckers.)
1027 Adjust the 1867 transition in Alaska to better reflect the
1028 historical record, by changing it to occur on 1867-10-18 at 15:30
1029 Sitka time rather than at the start of 1867-10-17 local time.
1030 Although strictly speaking this is accurate only for Sitka,
1031 the rest of Alaska's blanks need to be filled in somehow.
1033 Fix off-by-one errors in UT offsets for Adak and Nome before 1867.
1034 (Thanks to Michael Deckers.)
1036 Add 7 s to the UT offset in Asia/Yangon before 1920.
1038 Changes to zone names
1040 Remove Canada/East-Saskatchewan from the 'backward' file, as it
1041 exceeded the 14-character limit and was an unused misnomer anyway.
1043 Changes to build procedure
1045 To support applications that prefer to read time zone data in text
1046 form, two zic input files tzdata.zi and leapseconds are now
1047 installed by default. The commands 'zic tzdata.zi' and 'zic -L
1048 leapseconds tzdata.zi' can reproduce the tzdata binary files
1049 without and with leap seconds, respectively. To prevent these two
1050 new files from being installed, use 'make TZDATA_TEXT=', and to
1051 suppress leap seconds from the tzdata text installation, use 'make
1052 TZDATA_TEXT=tzdata.zi'.
1054 'make BACKWARD=' now suppresses backward-compatibility names
1055 like 'US/Pacific' that are defined in the 'backward' and
1058 'make check' now works on systems that lack a UTF-8 locale,
1059 or that lack the nsgmls program. Set UTF8_LOCALE to configure
1060 the name of a UTF-8 locale, if you have one.
1062 Y2K runtime checks are no longer enabled by default. Add
1063 -DDEPRECATE_TWO_DIGIT_YEARS to CFLAGS to enable them, instead of
1064 adding -DNO_RUN_TIME_WARNINGS_ABOUT_YEAR_2000_PROBLEMS_THANK_YOU
1065 to disable them. (New name suggested by Brian Inglis.)
1067 The build procedure for zdump now works on AIX 7.1.
1068 (Problem reported by Kees Dekker.)
1072 zic and the reference runtime now reject multiple leap seconds
1073 within 28 days of each other, or leap seconds before the Epoch.
1074 As a result, support for double leap seconds, which was
1075 obsolescent and undocumented, has been removed. Double leap
1076 seconds were an error in the C89 standard; they have never existed
1077 in civil timekeeping. (Thanks to Robert Elz and Bradley White for
1078 noticing glitches in the code that uncovered this problem.)
1080 zic now warns about use of the obsolescent and undocumented -y
1081 option, and about use of the obsolescent TYPE field of Rule lines.
1083 zic now allows unambiguous abbreviations like "Sa" and "Su" for
1084 weekdays; formerly it rejected them due to a bug. Conversely, zic
1085 no longer considers non-prefixes to be abbreviations; for example,
1086 it no longer accepts "lF" as an abbreviation for "lastFriday".
1087 Also, zic warns about the undocumented usage with a "last-"
1088 prefix, e.g., "last-Fri".
1090 Similarly, zic now accepts the unambiguous abbreviation "L" for
1091 "Link" in ordinary context and for "Leap" in leap-second context.
1092 Conversely, zic no longer accepts non-prefixes such as "La" as
1093 abbreviations for words like "Leap".
1095 zic no longer accepts leap second lines in ordinary input, or
1096 ordinary lines in leap second input. Formerly, zic sometimes
1097 warned about this undocumented usage and handled it incorrectly.
1099 The new macro HAVE_TZNAME governs whether the tzname external
1100 variable is exported, instead of USG_COMPAT. USG_COMPAT now
1101 governs only the external variables "timezone" and "daylight".
1102 This change is needed because the three variables are not in the
1103 same category: although POSIX requires tzname, it specifies the
1104 other two variables as optional. Also, USG_COMPAT is now 1 or 0:
1105 if not defined, the code attempts to guess it from other macros.
1107 localtime.c and difftime.c no longer require stdio.h, and .c files
1108 other than zic.c no longer require sys/wait.h.
1110 zdump.c no longer assumes snprintf. (Reported by Jonathan Leffler.)
1112 Calculation of time_t extrema works around a bug in GCC 4.8.4
1113 (Reported by Stan Shebs and Joseph Myers.)
1115 zic.c no longer mistranslates formats of line numbers in non-English
1116 locales. (Problem reported by Benno Schulenberg.)
1118 Several minor changes have been made to the code to make it a
1119 bit easier to port to MS-Windows and Solaris. (Thanks to Kees
1120 Dekker for reporting the problems.)
1122 Changes to documentation and commentary
1124 The two new files 'theory.html' and 'calendars' contain the
1125 contents of the removed file 'Theory'. The goal is to document
1126 tzdb theory more accessibly.
1128 The zic man page now documents abbreviation rules.
1130 tz-link.htm now covers how to apply tzdata changes to clients.
1131 (Thanks to Jorge Fábregas for the AIX link.) It also mentions MySQL.
1133 The leap-seconds.list URL has been updated to something that is
1134 more reliable for tzdb. (Thanks to Tim Parenti and Brian Inglis.)
1136 Release 2017b - 2017-03-17 07:30:38 -0700
1138 Briefly: Haiti has resumed DST.
1140 Changes to past and future timestamps
1142 Haiti resumed observance of DST in 2017. (Thanks to Steffen Thorsen.)
1144 Changes to past timestamps
1146 Liberia changed from -004430 to +00 on 1972-01-07, not 1972-05-01.
1148 Use "MMT" to abbreviate Liberia's time zone before 1972, as "-004430"
1149 is one byte over the POSIX limit. (Problem reported by Derick Rethans.)
1153 The reference localtime implementation now falls back on the
1154 current US daylight-saving transition rules rather than the
1155 1987-2006 rules. This fallback occurs only when (1) the TZ
1156 environment variable has a value like "AST4ADT" that asks
1157 for daylight saving time but does not specify the rules, (2) there
1158 is no file by that name, and (3) the TZDEFRULES file cannot be
1159 loaded. (Thanks to Tom Lane.)
1162 Release 2017a - 2017-02-28 00:05:36 -0800
1164 Briefly: Southern Chile moves from -04/-03 to -03, and Mongolia
1167 Changes to future timestamps
1169 Mongolia no longer observes DST. (Thanks to Ganbold Tsagaankhuu.)
1171 Chile's Region of Magallanes moves from -04/-03 to -03 year-round.
1172 Its clocks diverge from America/Santiago starting 2017-05-13 at
1173 23:00, hiving off a new zone America/Punta_Arenas. Although the
1174 Chilean government says this change expires in May 2019, for now
1175 assume it's permanent. (Thanks to Juan Correa and Deborah
1176 Goldsmith.) This also affects Antarctica/Palmer.
1178 Changes to past timestamps
1180 Fix many entries for historical timestamps for Europe/Madrid
1181 before 1979, to agree with tables compiled by Pere Planesas of the
1182 National Astronomical Observatory of Spain. As a side effect,
1183 this changes some timestamps for Africa/Ceuta before 1929, which
1184 are probably guesswork anyway. (Thanks to Steve Allen and
1185 Pierpaolo Bernardi for the heads-ups, and to Michael Deckers for
1186 correcting the 1901 transition.)
1188 Ecuador observed DST from 1992-11-28 to 1993-02-05.
1189 (Thanks to Alois Treindl.)
1191 Asia/Atyrau and Asia/Oral were at +03 (not +04) before 1930-06-21.
1192 (Thanks to Stepan Golosunov.)
1194 Changes to past and future time zone abbreviations
1196 Switch to numeric time zone abbreviations for South America, as
1197 part of the ongoing project of removing invented abbreviations.
1198 This avoids the need to invent an abbreviation for the new Chilean
1199 new zone. Similarly, switch from invented to numeric time zone
1200 abbreviations for Afghanistan, American Samoa, the Azores,
1201 Bangladesh, Bhutan, the British Indian Ocean Territory, Brunei,
1202 Cape Verde, Chatham Is, Christmas I, Cocos (Keeling) Is, Cook Is,
1203 Dubai, East Timor, Eucla, Fiji, French Polynesia, Greenland,
1204 Indochina, Iran, Iraq, Kiribati, Lord Howe, Macquarie, Malaysia,
1205 the Maldives, Marshall Is, Mauritius, Micronesia, Mongolia,
1206 Myanmar, Nauru, Nepal, New Caledonia, Niue, Norfolk I, Palau,
1207 Papua New Guinea, the Philippines, Pitcairn, Qatar, Réunion, St
1208 Pierre & Miquelon, Samoa, Saudi Arabia, Seychelles, Singapore,
1209 Solomon Is, Tokelau, Tuvalu, Wake, Vanuatu, Wallis & Futuna, and
1210 Xinjiang; for 20-minute daylight saving time in Ghana before 1943;
1211 for half-hour daylight saving time in Belize before 1944 and in
1212 the Dominican Republic before 1975; and for Canary Islands before
1213 1946, for Guinea-Bissau before 1975, for Iceland before 1969, for
1214 Indian Summer Time before 1942, for Indonesia before around 1964,
1215 for Kenya before 1960, for Liberia before 1973, for Madeira before
1216 1967, for Namibia before 1943, for the Netherlands in 1937-9, for
1217 Pakistan before 1971, for Western Sahara before 1977, and for
1218 Zaporozhye in 1880-1924.
1220 For Alaska time from 1900 through 1967, instead of "CAT" use the
1221 abbreviation "AST", the abbreviation commonly used at the time
1222 (Atlantic Standard Time had not been standardized yet). Use "AWT"
1223 and "APT" instead of the invented abbreviations "CAWT" and "CAPT".
1225 Use "CST" and "CDT" instead of invented abbreviations for Macau
1226 before 1999 and Taiwan before 1938, and use "JST" instead of the
1227 invented abbreviation "JCST" for Japan and Korea before 1938.
1229 Change to database entry category
1231 Move the Pacific/Johnston link from 'australasia' to 'backward',
1232 since Johnston is now uninhabited.
1236 zic no longer mishandles some transitions in January 2038 when it
1237 attempts to work around Qt bug 53071. This fixes a bug affecting
1238 Pacific/Tongatapu that was introduced in zic 2016e. localtime.c
1239 now contains a workaround, useful when loading a file generated by
1240 a buggy zic. (Problem and localtime.c fix reported by Bradley
1243 zdump -i now outputs non-hour numeric time zone abbreviations
1244 without a colon, e.g., "+0530" rather than "+05:30". This agrees
1245 with zic %z and with common practice, and simplifies auditing of
1248 zdump is now buildable again with -DUSE_LTZ=0.
1249 (Problem reported by Joseph Myers.)
1251 zdump.c now always includes private.h, to avoid code duplication
1252 with private.h. (Problem reported by Kees Dekker.)
1254 localtime.c no longer mishandles early or late timestamps
1255 when TZ is set to a POSIX-style string that specifies DST.
1256 (Problem reported by Kees Dekker.)
1258 date and strftime now cause %z to generate "-0000" instead of
1259 "+0000" when the UT offset is zero and the time zone abbreviation
1262 Changes to documentation and commentary
1264 The 'Theory' file now better documents choice of historical time
1265 zone abbreviations. (Problems reported by Michael Deckers.)
1267 tz-link.htm now covers leap smearing, which is popular in clouds.
1270 Release 2016j - 2016-11-22 23:17:13 -0800
1272 Briefly: Saratov, Russia moves from +03 to +04 on 2016-12-04.
1274 Changes to future timestamps
1276 Saratov, Russia switches from +03 to +04 on 2016-12-04 at 02:00.
1277 This hives off a new zone Europe/Saratov from Europe/Volgograd.
1278 (Thanks to Yuri Konotopov and Stepan Golosunov.)
1280 Changes to past timestamps
1282 The new zone Asia/Atyrau for Atyraū Region, Kazakhstan, is like
1283 Asia/Aqtau except it switched from +05/+06 to +04/+05 in spring
1284 1999, not fall 1994. (Thanks to Stepan Golosunov.)
1286 Changes to past time zone abbreviations
1288 Asia/Gaza and Asia/Hebron now use "EEST", not "EET", to denote
1289 summer time before 1948. The old use of "EET" was a typo.
1293 zic no longer mishandles file systems that lack hard links, fixing
1294 bugs introduced in 2016g. (Problems reported by Tom Lane.)
1295 Also, when the destination already contains symbolic links, zic
1296 should now work better on systems where the 'link' system call
1297 does not follow symbolic links.
1299 Changes to documentation and commentary
1301 tz-link.htm now documents the relationship between release version
1302 numbers and development-repository commit tags. (Suggested by
1305 The 'Theory' file now documents UT.
1307 iso3166.tab now accents "Curaçao", and commentary now mentions
1308 the names "Cabo Verde" and "Czechia". (Thanks to Jiří Boháč.)
1311 Release 2016i - 2016-11-01 23:19:52 -0700
1313 Briefly: Cyprus split into two time zones on 2016-10-30, and Tonga
1314 reintroduces DST on 2016-11-06.
1316 Changes to future timestamps
1318 Pacific/Tongatapu begins DST on 2016-11-06 at 02:00, ending on
1319 2017-01-15 at 03:00. Assume future observances in Tonga will be
1320 from the first Sunday in November through the third Sunday in
1321 January, like Fiji. (Thanks to Pulu ʻAnau.) Switch to numeric
1322 time zone abbreviations for this zone.
1324 Changes to past and future timestamps
1326 Northern Cyprus is now +03 year round, causing a split in Cyprus
1327 time zones starting 2016-10-30 at 04:00. This creates a zone
1328 Asia/Famagusta. (Thanks to Even Scharning and Matt Johnson.)
1330 Antarctica/Casey switched from +08 to +11 on 2016-10-22.
1331 (Thanks to Steffen Thorsen.)
1333 Changes to past timestamps
1335 Several corrections were made for pre-1975 timestamps in Italy.
1336 These affect Europe/Malta, Europe/Rome, Europe/San_Marino, and
1339 First, the 1893-11-01 00:00 transition in Italy used the new UT
1340 offset (+01), not the old (+00:49:56). (Thanks to Michael
1343 Second, rules for daylight saving in Italy were changed to agree
1344 with Italy's National Institute of Metrological Research (INRiM)
1345 except for 1944, as follows (thanks to Pierpaolo Bernardi, Brian
1346 Inglis, and Michael Deckers):
1348 The 1916-06-03 transition was at 24:00, not 00:00.
1350 The 1916-10-01, 1919-10-05, and 1920-09-19 transitions were at
1353 The 1917-09-30 and 1918-10-06 transitions were at 24:00, not
1356 The 1944-09-17 transition was at 03:00, not 01:00. This
1357 particular change is taken from Italian law as INRiM's table,
1358 (which says 02:00) appears to have a typo here. Also, keep the
1359 1944-04-03 transition for Europe/Rome, as Rome was controlled by
1362 The 1967-1970 and 1972-1974 fallback transitions were at 01:00,
1367 The code should now be buildable on AmigaOS merely by setting the
1368 appropriate Makefile variables. (From a patch by Carsten Larsen.)
1371 Release 2016h - 2016-10-19 23:17:57 -0700
1373 Changes to future timestamps
1375 Asia/Gaza and Asia/Hebron end DST on 2016-10-29 at 01:00, not
1376 2016-10-21 at 00:00. (Thanks to Sharef Mustafa.) Predict that
1377 future fall transitions will be on the last Saturday of October
1378 at 01:00, which is consistent with predicted spring transitions
1379 on the last Saturday of March. (Thanks to Tim Parenti.)
1381 Changes to past timestamps
1383 In Turkey, transitions in 1986-1990 were at 01:00 standard time
1384 not at 02:00, and the spring 1994 transition was on March 20, not
1385 March 27. (Thanks to Kıvanç Yazan.)
1387 Changes to past and future time zone abbreviations
1389 Asia/Colombo now uses numeric time zone abbreviations like "+0530"
1390 instead of alphabetic ones like "IST" and "LKT". Various
1391 English-language sources use "IST", "LKT" and "SLST", with no
1392 working consensus. (Usage of "SLST" mentioned by Sadika
1397 zic no longer mishandles relativizing file names when creating
1398 symbolic links like /etc/localtime, when these symbolic links
1399 are outside the usual directory hierarchy. This fixes a bug
1400 introduced in 2016g. (Problem reported by Andreas Stieger.)
1402 Changes to build procedure
1404 New rules 'traditional_tarballs' and 'traditional_signatures' for
1405 building just the traditional-format distribution. (Requested by
1408 The file 'version' is now put into the tzdata tarball too.
1409 (Requested by Howard Hinnant.)
1411 Changes to documentation and commentary
1413 The 'Theory' file now has a section on interface stability.
1414 (Requested by Paul Koning.) It also mentions features like
1415 tm_zone and localtime_rz that have long been supported by the
1418 tz-link.htm has improved coverage of time zone boundaries suitable
1419 for geolocation. (Thanks to heads-ups from Evan Siroky and Matt
1422 The US commentary now mentions Allen and the "day of two noons".
1424 The Fiji commentary mentions the government's 2016-10-03 press
1425 release. (Thanks to Raymond Kumar.)
1428 Release 2016g - 2016-09-13 08:56:38 -0700
1430 Changes to future timestamps
1432 Turkey switched from EET/EEST (+02/+03) to permanent +03,
1433 effective 2016-09-07. (Thanks to Burak AYDIN.) Use "+03" rather
1434 than an invented abbreviation for the new time.
1436 New leap second 2016-12-31 23:59:60 UTC as per IERS Bulletin C 52.
1437 (Thanks to Tim Parenti.)
1439 Changes to past timestamps
1441 For America/Los_Angeles, spring-forward transition times have been
1442 corrected from 02:00 to 02:01 in 1948, and from 02:00 to 01:00 in
1445 For zones using Soviet time on 1919-07-01, transitions to UT-based
1446 time were at 00:00 UT, not at 02:00 local time. The affected
1447 zones are Europe/Kirov, Europe/Moscow, Europe/Samara, and
1448 Europe/Ulyanovsk. (Thanks to Alexander Belopolsky.)
1450 Changes to past and future time zone abbreviations
1452 The Factory zone now uses the time zone abbreviation -00 instead
1453 of a long English-language string, as -00 is now the normal way to
1454 represent an undefined time zone.
1456 Several zones in Antarctica and the former Soviet Union, along
1457 with zones intended for ships at sea that cannot use POSIX TZ
1458 strings, now use numeric time zone abbreviations instead of
1459 invented or obsolete alphanumeric abbreviations. The affected
1460 zones are Antarctica/Casey, Antarctica/Davis,
1461 Antarctica/DumontDUrville, Antarctica/Mawson, Antarctica/Rothera,
1462 Antarctica/Syowa, Antarctica/Troll, Antarctica/Vostok,
1463 Asia/Anadyr, Asia/Ashgabat, Asia/Baku, Asia/Bishkek, Asia/Chita,
1464 Asia/Dushanbe, Asia/Irkutsk, Asia/Kamchatka, Asia/Khandyga,
1465 Asia/Krasnoyarsk, Asia/Magadan, Asia/Omsk, Asia/Sakhalin,
1466 Asia/Samarkand, Asia/Srednekolymsk, Asia/Tashkent, Asia/Tbilisi,
1467 Asia/Ust-Nera, Asia/Vladivostok, Asia/Yakutsk, Asia/Yekaterinburg,
1468 Asia/Yerevan, Etc/GMT-14, Etc/GMT-13, Etc/GMT-12, Etc/GMT-11,
1469 Etc/GMT-10, Etc/GMT-9, Etc/GMT-8, Etc/GMT-7, Etc/GMT-6, Etc/GMT-5,
1470 Etc/GMT-4, Etc/GMT-3, Etc/GMT-2, Etc/GMT-1, Etc/GMT+1, Etc/GMT+2,
1471 Etc/GMT+3, Etc/GMT+4, Etc/GMT+5, Etc/GMT+6, Etc/GMT+7, Etc/GMT+8,
1472 Etc/GMT+9, Etc/GMT+10, Etc/GMT+11, Etc/GMT+12, Europe/Kaliningrad,
1473 Europe/Minsk, Europe/Samara, Europe/Volgograd, and
1474 Indian/Kerguelen. For Europe/Moscow the invented abbreviation MSM
1475 was replaced by +05, whereas MSK and MSD were kept as they are not
1476 our invention and are widely used.
1478 Changes to zone names
1480 Rename Asia/Rangoon to Asia/Yangon, with a backward compatibility link.
1481 (Thanks to David Massoud.)
1485 zic no longer generates binary files containing POSIX TZ-like
1486 strings that disagree with the local time type after the last
1487 explicit transition in the data. This fixes a bug with
1488 Africa/Casablanca and Africa/El_Aaiun in some year-2037 timestamps
1489 on the reference platform. (Thanks to Alexander Belopolsky for
1490 reporting the bug and suggesting a way forward.)
1492 If the installed localtime and/or posixrules files are symbolic
1493 links, zic now keeps them symbolic links when updating them, for
1494 compatibility with platforms like OpenSUSE where other programs
1495 configure these files as symlinks.
1497 zic now avoids hard linking to symbolic links, avoids some
1498 unnecessary mkdir and stat system calls, and uses shorter file
1501 zdump has a new -i option to generate transitions in a
1502 more-compact but still human-readable format. This option is
1503 experimental, and the output format may change in future versions.
1504 (Thanks to Jon Skeet for suggesting that an option was needed,
1505 and thanks to Tim Parenti and Chris Rovick for further comments.)
1507 Changes to build procedure
1509 An experimental distribution format is available, in addition
1510 to the traditional format which will continue to be distributed.
1511 The new format is a tarball tzdb-VERSION.tar.lz with signature
1512 file tzdb-VERSION.tar.lz.asc. It unpacks to a top-level directory
1513 tzdb-VERSION containing the code and data of the traditional
1514 two-tarball format, along with extra data that may be useful.
1515 (Thanks to Antonio Diaz Diaz, Oscar van Vlijmen, and many others
1516 for comments about the experimental format.)
1518 The release version number is now more accurate in the usual case
1519 where releases are built from a Git repository. For example, if
1520 23 commits and some working-file changes have been made since
1521 release 2016g, the version number is now something like
1522 '2016g-23-g50556e3-dirty' instead of the misleading '2016g'.
1523 Tagged releases use the same version number format as before,
1524 e.g., '2016g'. To support the more-accurate version number, its
1525 specification has moved from a line in the Makefile to a new
1526 source file 'version'.
1528 The experimental distribution contains a file to2050.tzs that
1529 contains what should be the output of 'zdump -i -c 2050' on
1530 primary zones. If this file is available, 'make check' now checks
1531 that zdump generates this output.
1533 'make check_web' now works on Fedora-like distributions.
1535 Changes to documentation and commentary
1537 tzfile.5 now documents the new restriction on POSIX TZ-like
1538 strings that is now implemented by zic.
1540 Comments now cite URLs for some 1917-1921 Russian DST decrees.
1541 (Thanks to Alexander Belopolsky.)
1543 tz-link.htm mentions JuliaTime (thanks to Curtis Vogt) and Time4J
1544 (thanks to Meno Hochschild) and ThreeTen-Extra, and its
1545 description of Java 8 has been brought up to date (thanks to
1546 Stephen Colebourne). Its description of local time on Mars has
1547 been updated to match current practice, and URLs have been updated
1548 and some obsolete ones removed.
1551 Release 2016f - 2016-07-05 16:26:51 +0200
1553 Changes affecting future timestamps
1555 The Egyptian government changed its mind on short notice, and
1556 Africa/Cairo will not introduce DST starting 2016-07-07 after all.
1557 (Thanks to Mina Samuel.)
1559 Asia/Novosibirsk switches from +06 to +07 on 2016-07-24 at 02:00.
1560 (Thanks to Stepan Golosunov.)
1562 Changes to past and future timestamps
1564 Asia/Novokuznetsk and Asia/Novosibirsk now use numeric time zone
1565 abbreviations instead of invented ones.
1567 Changes affecting past timestamps
1569 Europe/Minsk's 1992-03-29 spring-forward transition was at 02:00 not 00:00.
1570 (Thanks to Stepan Golosunov.)
1573 Release 2016e - 2016-06-14 08:46:16 -0700
1575 Changes affecting future timestamps
1577 Africa/Cairo observes DST in 2016 from July 7 to the end of October.
1578 Guess October 27 and 24:00 transitions. (Thanks to Steffen Thorsen.)
1579 For future years, guess April's last Thursday to October's last
1580 Thursday except for Ramadan.
1582 Changes affecting past timestamps
1584 Locations while uninhabited now use '-00', not 'zzz', as a
1585 placeholder time zone abbreviation. This is inspired by Internet
1586 RFC 3339 and is more consistent with numeric time zone
1587 abbreviations already used elsewhere. The change affects several
1588 arctic and antarctic locations, e.g., America/Cambridge_Bay before
1589 1920 and Antarctica/Troll before 2005.
1591 Asia/Baku's 1992-09-27 transition from +04 (DST) to +04 (non-DST) was
1592 at 03:00, not 23:00 the previous day. (Thanks to Michael Deckers.)
1596 zic now outputs a dummy transition at time 2**31 - 1 in zones
1597 whose POSIX-style TZ strings contain a '<'. This mostly works
1598 around Qt bug 53071 <https://bugreports.qt.io/browse/QTBUG-53071>.
1599 (Thanks to Zhanibek Adilbekov for reporting the Qt bug.)
1601 Changes affecting documentation and commentary
1603 tz-link.htm says why governments should give plenty of notice for
1604 time zone or DST changes, and refers to Matt Johnson's blog post.
1606 tz-link.htm mentions Tzdata for Elixir. (Thanks to Matt Johnson.)
1609 Release 2016d - 2016-04-17 22:50:29 -0700
1611 Changes affecting future timestamps
1613 America/Caracas switches from -0430 to -04 on 2016-05-01 at 02:30.
1614 (Thanks to Alexander Krivenyshev for the heads-up.)
1616 Asia/Magadan switches from +10 to +11 on 2016-04-24 at 02:00.
1617 (Thanks to Alexander Krivenyshev and Matt Johnson.)
1619 New zone Asia/Tomsk, split off from Asia/Novosibirsk. It covers
1620 Tomsk Oblast, Russia, which switches from +06 to +07 on 2016-05-29
1621 at 02:00. (Thanks to Stepan Golosunov.)
1623 Changes affecting past timestamps
1625 New zone Europe/Kirov, split off from Europe/Volgograd. It covers
1626 Kirov Oblast, Russia, which switched from +04/+05 to +03/+04 on
1627 1989-03-26 at 02:00, roughly a year after Europe/Volgograd made
1628 the same change. (Thanks to Stepan Golosunov.)
1630 Russia and nearby locations had daylight-saving transitions on
1631 1992-03-29 at 02:00 and 1992-09-27 at 03:00, instead of on
1632 1992-03-28 at 23:00 and 1992-09-26 at 23:00. (Thanks to Stepan
1635 Many corrections to historical time in Kazakhstan from 1991
1636 through 2005. (Thanks to Stepan Golosunov.) Replace Kazakhstan's
1637 invented time zone abbreviations with numeric abbreviations.
1639 Changes to commentary
1641 Mention Internet RFCs 7808 (TZDIST) and 7809 (CalDAV time zone references).
1644 Release 2016c - 2016-03-23 00:51:27 -0700
1646 Changes affecting future timestamps
1648 Azerbaijan no longer observes DST. (Thanks to Steffen Thorsen.)
1650 Chile reverts from permanent to seasonal DST. (Thanks to Juan
1651 Correa for the heads-up, and to Tim Parenti for corrections.)
1652 Guess that future transitions are August's and May's second
1653 Saturdays at 24:00 mainland time. Also, call the period from
1654 2014-09-07 through 2016-05-14 daylight saving time instead of
1655 standard time, as that seems more appropriate now.
1657 Changes affecting past timestamps
1659 Europe/Kaliningrad and Europe/Vilnius changed from +03/+04 to
1660 +02/+03 on 1989-03-26, not 1991-03-31. Europe/Volgograd changed
1661 from +04/+05 to +03/+04 on 1988-03-27, not 1989-03-26.
1662 (Thanks to Stepan Golosunov.)
1664 Changes to commentary
1666 Several updates and URLs for historical and proposed Russian changes.
1667 (Thanks to Stepan Golosunov, Matt Johnson, and Alexander Krivenyshev.)
1670 Release 2016b - 2016-03-12 17:30:14 -0800
1674 Starting with release 2016b, some data entries cause zic implementations
1675 derived from tz releases 2005j through 2015e to issue warnings like
1676 "time zone abbreviation differs from POSIX standard (+03)".
1677 These warnings should not otherwise affect zic's output and can safely be
1678 ignored on today's platforms, as the warnings refer to a restriction in
1679 POSIX.1-1988 that was removed in POSIX.1-2001. One way to suppress the
1680 warnings is to upgrade to zic derived from tz releases 2015f and later.
1682 Changes affecting future timestamps
1684 New zones Europe/Astrakhan and Europe/Ulyanovsk for Astrakhan and
1685 Ulyanovsk Oblasts, Russia, both of which will switch from +03 to +04 on
1686 2016-03-27 at 02:00 local time. They need distinct zones since their
1687 post-1970 histories disagree. New zone Asia/Barnaul for Altai Krai and
1688 Altai Republic, Russia, which will switch from +06 to +07 on the same date
1689 and local time. The Astrakhan change is already official; the others have
1690 passed the first reading in the State Duma and are extremely likely.
1691 Also, Asia/Sakhalin moves from +10 to +11 on 2016-03-27 at 02:00.
1692 (Thanks to Alexander Krivenyshev for the heads-up, and to Matt Johnson
1693 and Stepan Golosunov for followup.)
1695 As a trial of a new system that needs less information to be made up,
1696 the new zones use numeric time zone abbreviations like "+04"
1697 instead of invented abbreviations like "ASTT".
1699 Haiti will not observe DST in 2016. (Thanks to Jean Antoine via
1702 Palestine's spring-forward transition on 2016-03-26 is at 01:00, not 00:00.
1703 (Thanks to Hannah Kreitem.) Guess future transitions will be March's last
1704 Saturday at 01:00, not March's last Friday at 24:00.
1706 Changes affecting past timestamps
1708 Europe/Chisinau observed DST during 1990, and switched from +04 to
1709 +03 at 1990-05-06 02:00, instead of switching from +03 to +02.
1710 (Thanks to Stepan Golosunov.)
1712 1991 abbreviations in Europe/Samara should be SAMT/SAMST, not
1713 KUYT/KUYST. (Thanks to Stepan Golosunov.)
1717 tzselect's diagnostics and checking, and checktab.awk's checking,
1718 have been improved. (Thanks to J William Piggott.)
1720 tzcode now builds under MinGW. (Thanks to Ian Abbott and Esben Haabendal.)
1722 tzselect now tests Julian-date TZ settings more accurately.
1723 (Thanks to J William Piggott.)
1725 Changes to commentary
1727 Comments in zone tables have been improved. (Thanks to J William Piggott.)
1729 tzselect again limits its menu comments so that menus fit on a
1730 24×80 alphanumeric display.
1732 A new web page tz-how-to.html. (Thanks to Bill Seymour.)
1734 In the Theory file, the description of possible time zone abbreviations in
1735 tzdata has been cleaned up, as the old description was unclear and
1736 inconsistent. (Thanks to Alain Mouette for reporting the problem.)
1739 Release 2016a - 2016-01-26 23:28:02 -0800
1741 Changes affecting future timestamps
1743 America/Cayman will not observe daylight saving this year after all.
1744 Revert our guess that it would. (Thanks to Matt Johnson.)
1746 Asia/Chita switches from +0800 to +0900 on 2016-03-27 at 02:00.
1747 (Thanks to Alexander Krivenyshev.)
1749 Asia/Tehran now has DST predictions for the year 2038 and later,
1750 to be March 21 00:00 to September 21 00:00. This is likely better
1751 than predicting no DST, albeit off by a day every now and then.
1753 Changes affecting past and future timestamps
1755 America/Metlakatla switched from PST all year to AKST/AKDT on
1756 2015-11-01 at 02:00. (Thanks to Steffen Thorsen.)
1758 America/Santa_Isabel has been removed, and replaced with a
1759 backward compatibility link to America/Tijuana. Its contents were
1760 apparently based on a misreading of Mexican legislation.
1762 Changes affecting past timestamps
1764 Asia/Karachi's two transition times in 2002 were off by a minute.
1765 (Thanks to Matt Johnson.)
1767 Changes affecting build procedure
1769 An installer can now combine leap seconds with use of the backzone file,
1770 e.g., with 'make PACKRATDATA=backzone REDO=posix_right zones'.
1771 The old 'make posix_packrat' rule is now marked as obsolescent.
1772 (Thanks to Ian Abbott for an initial implementation.)
1774 Changes affecting documentation and commentary
1776 A new file LICENSE makes it easier to see that the code and data
1777 are mostly public-domain. (Thanks to James Knight.) The three
1778 non-public-domain files now use the current (3-clause) BSD license
1779 instead of older versions of that license.
1781 tz-link.htm mentions the BDE library (thanks to Andrew Paprocki),
1782 CCTZ (thanks to Tim Parenti), TimeJones.com, and has a new section
1783 on editing tz source files (with a mention of Sublime zoneinfo,
1784 thanks to Gilmore Davidson).
1786 The Theory and asia files now mention the 2015 book "The Global
1787 Transformation of Time, 1870-1950", and cite a couple of reviews.
1789 The America/Chicago entry now documents the informal use of US
1790 central time in Fort Pierre, South Dakota. (Thanks to Rick
1791 McDermid, Matt Johnson, and Steve Jones.)
1794 Release 2015g - 2015-10-01 00:39:51 -0700
1796 Changes affecting future timestamps
1798 Turkey's 2015 fall-back transition is scheduled for Nov. 8, not Oct. 25.
1801 Norfolk moves from +1130 to +1100 on 2015-10-04 at 02:00 local time.
1802 (Thanks to Alexander Krivenyshev.)
1804 Fiji's 2016 fall-back transition is scheduled for January 17, not 24.
1805 (Thanks to Ken Rylander.)
1807 Fort Nelson, British Columbia will not fall back on 2015-11-01. It has
1808 effectively been on MST (-0700) since it advanced its clocks on 2015-03-08.
1809 New zone America/Fort_Nelson. (Thanks to Matt Johnson.)
1811 Changes affecting past timestamps
1813 Norfolk observed DST from 1974-10-27 02:00 to 1975-03-02 02:00.
1815 Changes affecting code
1817 localtime no longer mishandles America/Anchorage after 2037.
1818 (Thanks to Bradley White for reporting the bug.)
1820 On hosts with signed 32-bit time_t, localtime no longer mishandles
1821 Pacific/Fiji after 2038-01-16 14:00 UTC.
1823 The localtime module allows the variables 'timezone', 'daylight',
1824 and 'altzone' to be in common storage shared with other modules,
1825 and declares them in case the system <time.h> does not.
1826 (Problems reported by Kees Dekker.)
1828 On platforms with tm_zone, strftime.c now assumes it is not NULL.
1829 This simplifies the code and is consistent with zdump.c.
1830 (Problem reported by Christos Zoulas.)
1832 Changes affecting documentation
1834 The tzfile man page now documents that transition times denote the
1835 starts (not the ends) of the corresponding time periods.
1836 (Ambiguity reported by Bill Seymour.)
1839 Release 2015f - 2015-08-10 18:06:56 -0700
1841 Changes affecting future timestamps
1843 North Korea switches to +0830 on 2015-08-15. (Thanks to Steffen Thorsen.)
1844 The abbreviation remains "KST". (Thanks to Robert Elz.)
1846 Uruguay no longer observes DST. (Thanks to Steffen Thorsen
1849 Changes affecting past and future timestamps
1851 Moldova starts and ends DST at 00:00 UTC, not at 01:00 UTC.
1852 (Thanks to Roman Tudos.)
1854 Changes affecting data format and code
1856 zic's '-y YEARISTYPE' option is no longer documented. The TYPE
1857 field of a Rule line should now be '-'; the old values 'even',
1858 'odd', 'uspres', 'nonpres', 'nonuspres' were already undocumented.
1859 Although the implementation has not changed, these features do not
1860 work in the default installation, they are not used in the data,
1861 and they are now considered obsolescent.
1863 zic now checks that two rules don't take effect at the same time.
1864 (Thanks to Jon Skeet and Arthur David Olson.) Constraints on
1865 simultaneity are now documented.
1867 The two characters '%z' in a zone format now stand for the UT
1868 offset, e.g., '-07' for seven hours behind UT and '+0530' for
1869 five hours and thirty minutes ahead. This better supports time
1870 zone abbreviations conforming to POSIX.1-2001 and later.
1872 Changes affecting installed data files
1874 Comments for America/Halifax and America/Glace_Bay have been improved.
1875 (Thanks to Brian Inglis.)
1877 Data entries have been simplified for Atlantic/Canary, Europe/Simferopol,
1878 Europe/Sofia, and Europe/Tallinn. This yields slightly smaller
1879 installed data files for Europe/Simferopol and Europe/Tallinn.
1880 It does not affect timestamps. (Thanks to Howard Hinnant.)
1882 Changes affecting code
1884 zdump and zic no longer warn about valid time zone abbreviations
1887 Some Visual Studio 2013 warnings have been suppressed.
1888 (Thanks to Kees Dekker.)
1890 'date' no longer sets the time of day and its -a, -d, -n and -t
1891 options have been removed. Long obsolescent, the implementation
1892 of these features had porting problems. Builders no longer need
1893 to configure HAVE_ADJTIME, HAVE_SETTIMEOFDAY, or HAVE_UTMPX_H.
1894 (Thanks to Kees Dekker for pointing out the problem.)
1896 Changes affecting documentation
1898 The Theory file mentions naming issues earlier, as these seem to be
1899 poorly publicized (thanks to Gilmore Davidson for reporting the problem).
1901 tz-link.htm mentions Time Zone Database Parser (thanks to Howard Hinnant).
1903 Mention that Herbert Samuel introduced the term "Summer Time".
1906 Release 2015e - 2015-06-13 10:56:02 -0700
1908 Changes affecting future timestamps
1910 Morocco will suspend DST from 2015-06-14 03:00 through 2015-07-19 02:00,
1911 not 06-13 and 07-18 as we had guessed. (Thanks to Milamber.)
1913 Assume Cayman Islands will observe DST starting next year, using US rules.
1914 Although it isn't guaranteed, it is the most likely.
1916 Changes affecting data format
1918 The file 'iso3166.tab' now uses UTF-8, so that its entries can better
1919 spell the names of Åland Islands, Côte d'Ivoire, and Réunion.
1921 Changes affecting code
1923 When displaying data, tzselect converts it to the current locale's
1924 encoding if the iconv command works. (Problem reported by random832.)
1926 tzselect no longer mishandles Dominica, fixing a bug introduced
1927 in Release 2014f. (Problem reported by Owen Leibman.)
1929 zic -l no longer fails when compiled with -DTZDEFAULT=\"/etc/localtime\".
1930 This fixes a bug introduced in Release 2014f.
1931 (Problem reported by Leonardo Chiquitto.)
1934 Release 2015d - 2015-04-24 08:09:46 -0700
1936 Changes affecting future timestamps
1938 Egypt will not observe DST in 2015 and will consider canceling it
1939 permanently. For now, assume no DST indefinitely.
1940 (Thanks to Ahmed Nazmy and Tim Parenti.)
1942 Changes affecting past timestamps
1944 America/Whitehorse switched from UT -09 to -08 on 1967-05-28, not
1945 1966-07-01. Also, Yukon's time zone history is documented better.
1946 (Thanks to Brian Inglis and Dennis Ferguson.)
1948 Change affecting past and future time zone abbreviations
1950 The abbreviations for Hawaii-Aleutian standard and daylight times
1951 have been changed from HAST/HADT to HST/HDT, as per US Government
1952 Printing Office style. This affects only America/Adak since 1983,
1953 as America/Honolulu was already using the new style.
1955 Changes affecting code
1957 zic has some minor performance improvements.
1960 Release 2015c - 2015-04-11 08:55:55 -0700
1962 Changes affecting future timestamps
1964 Egypt's spring-forward transition is at 24:00 on April's last Thursday,
1965 not 00:00 on April's last Friday. 2015's transition will therefore be on
1966 Thursday, April 30 at 24:00, not Friday, April 24 at 00:00. Similar fixes
1967 apply to 2026, 2037, 2043, etc. (Thanks to Steffen Thorsen.)
1969 Changes affecting past timestamps
1971 The following changes affect some pre-1991 Chile-related timestamps
1972 in America/Santiago, Antarctica/Palmer, and Pacific/Easter.
1974 The 1910 transition was January 10, not January 1.
1976 The 1918 transition was September 10, not September 1.
1978 The UT -04 time observed from 1932 to 1942 is now considered to
1979 be standard time, not year-round DST.
1981 Santiago observed DST (UT -03) from 1946-07-15 through
1982 1946-08-31, then reverted to standard time, then switched to -05
1985 Assume transitions before 1968 were at 00:00, since we have no data
1988 The spring 1988 transition was 1988-10-09, not 1988-10-02.
1989 The fall 1990 transition was 1990-03-11, not 1990-03-18.
1991 Assume no UT offset change for Pacific/Easter on 1890-01-01,
1992 and omit all transitions on Pacific/Easter from 1942 through 1946
1993 since we have no data suggesting that they existed.
1995 One more zone has been turned into a link, as it differed
1996 from an existing zone only for older timestamps. As usual,
1997 this change affects UT offsets in pre-1970 timestamps only.
1998 The zone's old contents have been moved to the 'backzone' file.
1999 The affected zone is America/Montreal.
2001 Changes affecting commentary
2003 Mention the TZUpdater tool.
2005 Mention "The Time Now". (Thanks to Brandon Ramsey.)
2008 Release 2015b - 2015-03-19 23:28:11 -0700
2010 Changes affecting future timestamps
2012 Mongolia will start observing DST again this year, from the last
2013 Saturday in March at 02:00 to the last Saturday in September at 00:00.
2014 (Thanks to Ganbold Tsagaankhuu.)
2016 Palestine will start DST on March 28, not March 27. Also,
2017 correct the fall 2014 transition from September 26 to October 24.
2018 Adjust future predictions accordingly. (Thanks to Steffen Thorsen.)
2020 Changes affecting past timestamps
2022 The 1982 zone shift in Pacific/Easter has been corrected, fixing a 2015a
2023 regression. (Thanks to Stuart Bishop for reporting the problem.)
2025 Some more zones have been turned into links, when they differed
2026 from existing zones only for older timestamps. As usual,
2027 these changes affect UT offsets in pre-1970 timestamps only.
2028 Their old contents have been moved to the 'backzone' file.
2029 The affected zones are: America/Antigua, America/Cayman,
2030 Pacific/Midway, and Pacific/Saipan.
2032 Changes affecting time zone abbreviations
2034 Correct the 1992-2010 DST abbreviation in Volgograd from "MSK" to "MSD".
2037 Changes affecting code
2039 Fix integer overflow bug in reference 'mktime' implementation.
2040 (Problem reported by Jörg Richter.)
2042 Allow -Dtime_tz=time_t compilations, and allow -Dtime_tz=... libraries
2043 to be used in the same executable as standard-library time_t functions.
2044 (Problems reported by Bradley White.)
2046 Changes affecting commentary
2048 Cite the recent Mexican decree changing Quintana Roo's time zone.
2049 (Thanks to Carlos Raúl Perasso.)
2051 Likewise for the recent Chilean decree. (Thanks to Eduardo Romero Urra.)
2053 Update info about Mars time.
2056 Release 2015a - 2015-01-29 22:35:20 -0800
2058 Changes affecting future timestamps
2060 The Mexican state of Quintana Roo, represented by America/Cancun,
2061 will shift from Central Time with DST to Eastern Time without DST
2062 on 2015-02-01 at 02:00. (Thanks to Steffen Thorsen and Gwillim Law.)
2064 Chile will not change clocks in April or thereafter; its new standard time
2065 will be its old daylight saving time. This affects America/Santiago,
2066 Pacific/Easter, and Antarctica/Palmer. (Thanks to Juan Correa.)
2068 New leap second 2015-06-30 23:59:60 UTC as per IERS Bulletin C 49.
2069 (Thanks to Tim Parenti.)
2071 Changes affecting past timestamps
2073 Iceland observed DST in 1919 and 1921, and its 1939 fallback
2074 transition was Oct. 29, not Nov. 29. Remove incorrect data from
2075 Shanks about time in Iceland between 1837 and 1908.
2077 Some more zones have been turned into links, when they differed
2078 from existing zones only for older timestamps. As usual,
2079 these changes affect UT offsets in pre-1970 timestamps only.
2080 Their old contents have been moved to the 'backzone' file.
2081 The affected zones are: Asia/Aden, Asia/Bahrain, Asia/Kuwait,
2084 Changes affecting code
2086 tzalloc now scrubs time zone abbreviations compatibly with the way
2087 that tzset always has, by replacing invalid bytes with '_' and by
2088 shortening too-long abbreviations.
2090 tzselect ports to POSIX awk implementations, no longer mishandles
2091 POSIX TZ settings when GNU awk is used, and reports POSIX TZ
2092 settings to the user. (Thanks to Stefan Kuhn.)
2094 Changes affecting build procedure
2096 'make check' now checks for links to links in the data.
2097 One such link (for Africa/Asmera) has been fixed.
2098 (Thanks to Stephen Colebourne for pointing out the problem.)
2100 Changes affecting commentary
2102 The leapseconds file commentary now mentions the expiration date.
2103 (Problem reported by Martin Burnicki.)
2105 Update Mexican Library of Congress URL.
2108 Release 2014j - 2014-11-10 17:37:11 -0800
2110 Changes affecting current and future timestamps
2112 Turks & Caicos' switch from US eastern time to UT -04 year-round
2113 did not occur on 2014-11-02 at 02:00. It's currently scheduled
2114 for 2015-11-01 at 02:00. (Thanks to Chris Walton.)
2116 Changes affecting past timestamps
2118 Many pre-1989 timestamps have been corrected for Asia/Seoul and
2119 Asia/Pyongyang, based on sources for the Korean-language Wikipedia
2120 entry for time in Korea. (Thanks to Sanghyuk Jung.) Also, no
2121 longer guess that Pyongyang mimicked Seoul time after World War II,
2122 as this is politically implausible.
2124 Some more zones have been turned into links, when they differed
2125 from existing zones only for older timestamps. As usual,
2126 these changes affect UT offsets in pre-1970 timestamps only.
2127 Their old contents have been moved to the 'backzone' file.
2128 The affected zones are: Africa/Addis_Ababa, Africa/Asmara,
2129 Africa/Dar_es_Salaam, Africa/Djibouti, Africa/Kampala,
2130 Africa/Mogadishu, Indian/Antananarivo, Indian/Comoro, and
2133 Changes affecting commentary
2135 The commentary is less enthusiastic about Shanks as a source,
2136 and is more careful to distinguish UT from UTC.
2139 Release 2014i - 2014-10-21 22:04:57 -0700
2141 Changes affecting future timestamps
2143 Pacific/Fiji will observe DST from 2014-11-02 02:00 to 2015-01-18 03:00.
2144 (Thanks to Ken Rylander for the heads-up.) Guess that future
2145 years will use a similar pattern.
2147 A new Zone Pacific/Bougainville, for the part of Papua New Guinea
2148 that plans to switch from UT +10 to +11 on 2014-12-28 at 02:00.
2149 (Thanks to Kiley Walbom for the heads-up.)
2151 Changes affecting time zone abbreviations
2153 Since Belarus is not changing its clocks even though Moscow is,
2154 the time zone abbreviation in Europe/Minsk is changing from FET
2155 to its more-traditional value MSK on 2014-10-26 at 01:00.
2156 (Thanks to Alexander Bokovoy for the heads-up about Belarus.)
2158 The new abbreviation IDT stands for the pre-1976 use of UT +08 in
2159 Indochina, to distinguish it better from ICT (+07).
2161 Changes affecting past timestamps
2163 Many timestamps have been corrected for Asia/Ho_Chi_Minh before 1976
2164 (thanks to Trần Ngọc Quân for an indirect pointer to Trần Tiến Bình's
2165 authoritative book). Asia/Ho_Chi_Minh has been added to
2166 zone1970.tab, to give tzselect users in Vietnam two choices,
2167 since north and south Vietnam disagreed after our 1970 cutoff.
2169 Asia/Phnom_Penh and Asia/Vientiane have been turned into links, as
2170 they differed from existing zones only for older timestamps. As
2171 usual, these changes affect pre-1970 timestamps only. Their old
2172 contents have been moved to the 'backzone' file.
2174 Changes affecting code
2176 The time-related library functions now set errno on failure, and
2177 some crashes in the new tzalloc-related library functions have
2178 been fixed. (Thanks to Christos Zoulas for reporting most of
2179 these problems and for suggesting fixes.)
2181 If USG_COMPAT is defined and the requested timestamp is standard time,
2182 the tz library's localtime and mktime functions now set the extern
2183 variable timezone to a value appropriate for that timestamp; and
2184 similarly for ALTZONE, daylight saving time, and the altzone variable.
2185 This change is a companion to the tzname change in 2014h, and is
2186 designed to make timezone and altzone more compatible with tzname.
2188 The tz library's functions now set errno to EOVERFLOW if they fail
2189 because the result cannot be represented. ctime and ctime_r now
2190 return NULL and set errno when a timestamp is out of range, rather
2191 than having undefined behavior.
2193 Some bugs associated with the new 2014g functions have been fixed.
2194 This includes a bug that largely incapacitated the new functions
2195 time2posix_z and posix2time_z. (Thanks to Christos Zoulas.)
2196 It also includes some uses of uninitialized variables after tzalloc.
2197 The new code uses the standard type 'ssize_t', which the Makefile
2198 now gives porting advice about.
2200 Changes affecting commentary
2202 Updated URLs for NRC Canada (thanks to Matt Johnson and Brian Inglis).
2205 Release 2014h - 2014-09-25 18:59:03 -0700
2207 Changes affecting past timestamps
2209 America/Jamaica's 1974 spring-forward transition was Jan. 6, not Apr. 28.
2211 Shanks says Asia/Novokuznetsk switched from LMT (not "NMT") on 1924-05-01,
2212 not 1920-01-06. The old entry was based on a misinterpretation of Shanks.
2214 Some more zones have been turned into links, when they differed
2215 from existing zones only for older timestamps. As usual,
2216 these changes affect UT offsets in pre-1970 timestamps only.
2217 Their old contents have been moved to the 'backzone' file.
2218 The affected zones are: Africa/Blantyre, Africa/Bujumbura,
2219 Africa/Gaborone, Africa/Harare, Africa/Kigali, Africa/Lubumbashi,
2220 Africa/Lusaka, Africa/Maseru, and Africa/Mbabane.
2222 Changes affecting code
2224 zdump -V and -v now output gmtoff= values on all platforms,
2225 not merely on platforms defining TM_GMTOFF.
2227 The tz library's localtime and mktime functions now set tzname to a value
2228 appropriate for the requested timestamp, and zdump now uses this
2229 on platforms not defining TM_ZONE, fixing a 2014g regression.
2230 (Thanks to Tim Parenti for reporting the problem.)
2232 The tz library no longer sets tzname if localtime or mktime fails.
2234 zdump -c no longer mishandles transitions near year boundaries.
2235 (Thanks to Tim Parenti for reporting the problem.)
2237 An access to uninitialized data has been fixed.
2238 (Thanks to Jörg Richter for reporting the problem.)
2240 When THREAD_SAFE is defined, the code ports to the C11 memory model.
2241 A memory leak has been fixed if ALL_STATE and THREAD_SAFE are defined
2242 and two threads race to initialize data used by gmtime-like functions.
2243 (Thanks to Andy Heninger for reporting the problems.)
2245 Changes affecting build procedure
2247 'make check' now checks better for properly-sorted data.
2249 Changes affecting documentation and commentary
2251 zdump's gmtoff=N output is now documented, and its isdst=D output
2252 is now documented to possibly output D values other than 0 or 1.
2254 zdump -c's treatment of years is now documented to use the
2255 Gregorian calendar and Universal Time without leap seconds,
2256 and its behavior at cutoff boundaries is now documented better.
2257 (Thanks to Arthur David Olson and Tim Parenti for reporting the problems.)
2259 Programs are now documented to use the proleptic Gregorian calendar.
2260 (Thanks to Alan Barrett for the suggestion.)
2262 Fractional-second GMT offsets have been documented for civil time
2263 in 19th-century Chennai, Jakarta, and New York.
2266 Release 2014g - 2014-08-28 12:31:23 -0700
2268 Changes affecting future timestamps
2270 Turks & Caicos is switching from US eastern time to UT -04
2271 year-round, modeled as a switch on 2014-11-02 at 02:00.
2272 [As noted in 2014j, this switch was later delayed.]
2274 Changes affecting past timestamps
2276 Time in Russia or the USSR before 1926 or so has been corrected by
2277 a few seconds in the following zones: Asia/Irkutsk,
2278 Asia/Krasnoyarsk, Asia/Omsk, Asia/Samarkand, Asia/Tbilisi,
2279 Asia/Vladivostok, Asia/Yakutsk, Europe/Riga, Europe/Samara. For
2280 Asia/Yekaterinburg the correction is a few minutes. (Thanks to
2281 Vladimir Karpinsky.)
2283 The Portuguese decree of 1911-05-26 took effect on 1912-01-01.
2284 This affects 1911 timestamps in Africa/Bissau, Africa/Luanda,
2285 Atlantic/Azores, and Atlantic/Madeira. Also, Lisbon's pre-1912
2286 GMT offset was -0:36:45 (rounded from -0:36:44.68), not -0:36:32.
2287 (Thanks to Stephen Colebourne for pointing to the decree.)
2289 Asia/Dhaka ended DST on 2009-12-31 at 24:00, not 23:59.
2291 A new file 'backzone' contains data which may appeal to
2292 connoisseurs of old timestamps, although it is out of scope for
2293 the tz database, is often poorly sourced, and contains some data
2294 that is known to be incorrect. The new file is not recommended
2295 for ordinary use and its entries are not installed by default.
2296 (Thanks to Lester Caine for the high-quality Jersey, Guernsey, and
2297 Isle of Man entries.)
2299 Some more zones have been turned into links, when they differed
2300 from existing zones only for older timestamps. As usual,
2301 these changes affect UT offsets in pre-1970 timestamps only.
2302 Their old contents have been moved to the 'backzone' file.
2303 The affected zones are: Africa/Bangui, Africa/Brazzaville,
2304 Africa/Douala, Africa/Kinshasa, Africa/Libreville, Africa/Luanda,
2305 Africa/Malabo, Africa/Niamey, and Africa/Porto-Novo.
2307 Changes affecting code
2309 Unless NETBSD_INSPIRED is defined to 0, the tz library now
2310 supplies functions for creating and using objects that represent
2311 timezones. The new functions are tzalloc, tzfree, localtime_rz,
2312 mktime_z, and (if STD_INSPIRED is also defined) posix2time_z and
2313 time2posix_z. They are intended for performance: for example,
2314 localtime_rz (unlike localtime_r) is trivially thread-safe without
2315 locking. (Thanks to Christos Zoulas for proposing NetBSD-inspired
2316 functions, and to Alan Barrett and Jonathan Lennox for helping to
2319 zdump now builds with the tz library unless USE_LTZ is defined to 0,
2320 This lets zdump use tz features even if the system library lacks them.
2321 To build zdump with the system library, use 'make CFLAGS=-DUSE_LTZ=0
2322 TZDOBJS=zdump.o CHECK_TIME_T_ALTERNATIVES='.
2324 zdump now uses localtime_rz if available, as it's significantly faster,
2325 and it can help zdump better diagnose invalid timezone names.
2326 Define HAVE_LOCALTIME_RZ to 0 to suppress this. HAVE_LOCALTIME_RZ
2327 defaults to 1 if NETBSD_INSPIRED && USE_LTZ. When localtime_rz is
2328 not available, zdump now uses localtime_r and tzset if available,
2329 as this is a bit cleaner and faster than plain localtime. Compile
2330 with -DHAVE_LOCALTIME_R=0 and/or -DHAVE_TZSET=0 if your system
2331 lacks these two functions.
2333 If THREAD_SAFE is defined to 1, the tz library is now thread-safe.
2334 Although not needed for tz's own applications, which are single-threaded,
2335 this supports POSIX better if the tz library is used in multithreaded apps.
2337 Some crashes have been fixed when zdump or the tz library is given
2338 invalid or outlandish input.
2340 The tz library no longer mishandles leap seconds on platforms with
2341 unsigned time_t in timezones that lack ordinary transitions after 1970.
2343 The tz code now attempts to infer TM_GMTOFF and TM_ZONE if not
2344 already defined, to make it easier to configure on common platforms.
2345 Define NO_TM_GMTOFF and NO_TM_ZONE to suppress this.
2347 Unless the new macro UNINIT_TRAP is defined to 1, the tz code now
2348 assumes that reading uninitialized memory yields garbage values
2349 but does not cause other problems such as traps.
2351 If TM_GMTOFF is defined and UNINIT_TRAP is 0, mktime is now
2352 more likely to guess right for ambiguous timestamps near
2353 transitions where tm_isdst does not change.
2355 If HAVE_STRFTIME_L is defined to 1, the tz library now defines
2356 strftime_l for compatibility with recent versions of POSIX.
2357 Only the C locale is supported, though. HAVE_STRFTIME_L defaults
2358 to 1 on recent POSIX versions, and to 0 otherwise.
2360 tzselect -c now uses a hybrid distance measure that works better
2361 in Africa. (Thanks to Alan Barrett for noting the problem.)
2363 The C source code now ports to NetBSD when GCC_DEBUG_FLAGS is used,
2364 or when time_tz is defined.
2366 When HAVE_UTMPX_H is set the 'date' command now builds on systems
2367 whose <utmpx.h> file does not define WTMPX_FILE, and when setting
2368 the date it updates the wtmpx file if _PATH_WTMPX is defined.
2369 This affects GNU/Linux and similar systems.
2371 For easier maintenance later, some C code has been simplified,
2372 some lint has been removed, and the code has been tweaked so that
2373 plain 'make' is more likely to work.
2375 The C type 'bool' is now used for boolean values, instead of 'int'.
2377 The long-obsolete LOCALE_HOME code has been removed.
2379 The long-obsolete 'gtime' function has been removed.
2381 Changes affecting build procedure
2383 'zdump' no longer links in ialloc.o, as it's not needed.
2385 'make check_time_t_alternatives' no longer assumes GNU diff.
2387 Changes affecting distribution tarballs
2389 The files checktab.awk and zoneinfo2tdf.pl are now distributed in
2390 the tzdata tarball instead of the tzcode tarball, since they help
2391 maintain the data. The NEWS and Theory files are now also
2392 distributed in the tzdata tarball, as they're relevant for data.
2393 (Thanks to Alan Barrett for pointing this out.) Also, the
2394 leapseconds.awk file is no longer distributed in the tzcode
2395 tarball, since it belongs in the tzdata tarball (where 2014f
2396 inadvertently also distributed it).
2398 Changes affecting documentation and commentary
2400 A new file CONTRIBUTING is distributed. (Thanks to Tim Parenti for
2401 suggesting a CONTRIBUTING file, and to Tony Finch and Walter Harms
2404 The man pages have been updated to use function prototypes,
2405 to document thread-safe variants like localtime_r, and to document
2406 the NetBSD-inspired functions tzalloc, tzfree, localtime_rz, and
2409 The fields in Link lines have been renamed to be more descriptive
2410 and more like the parameters of 'ln'. LINK-FROM has become TARGET,
2411 and LINK-TO has become LINK-NAME.
2413 tz-link.htm mentions the IETF's tzdist working group; Windows
2414 Runtime etc. (thanks to Matt Johnson); and HP-UX's tztab.
2416 Some broken URLs have been fixed in the commentary. (Thanks to
2419 Commentary about Philippines DST has been updated, and commentary
2420 on pre-1970 time in India has been added.
2423 Release 2014f - 2014-08-05 17:42:36 -0700
2425 Changes affecting future timestamps
2427 Russia will subtract an hour from most of its time zones on 2014-10-26
2428 at 02:00 local time. (Thanks to Alexander Krivenyshev.)
2429 There are a few exceptions: Magadan Oblast (Asia/Magadan) and Zabaykalsky
2430 Krai are subtracting two hours; conversely, Chukotka Autonomous Okrug
2431 (Asia/Anadyr), Kamchatka Krai (Asia/Kamchatka), Kemerovo Oblast
2432 (Asia/Novokuznetsk), and the Samara Oblast and the Udmurt Republic
2433 (Europe/Samara) are not changing their clocks. The changed zones are
2434 Europe/Kaliningrad, Europe/Moscow, Europe/Simferopol, Europe/Volgograd,
2435 Asia/Yekaterinburg, Asia/Omsk, Asia/Novosibirsk, Asia/Krasnoyarsk,
2436 Asia/Irkutsk, Asia/Yakutsk, Asia/Vladivostok, Asia/Khandyga,
2437 Asia/Sakhalin, and Asia/Ust-Nera; Asia/Magadan will have two hours
2438 subtracted; and Asia/Novokuznetsk's time zone abbreviation is affected,
2439 but not its UTC offset. Two zones are added: Asia/Chita (split
2440 from Asia/Yakutsk, and also with two hours subtracted) and
2441 Asia/Srednekolymsk (split from Asia/Magadan, but with only one hour
2442 subtracted). (Thanks to Tim Parenti for much of the above.)
2444 Changes affecting time zone abbreviations
2446 Australian eastern time zone abbreviations are now AEST/AEDT not EST,
2447 and similarly for the other Australian zones. That is, for eastern
2448 standard and daylight saving time the abbreviations are AEST and AEDT
2449 instead of the former EST for both; similarly, ACST/ACDT, ACWST/ACWDT,
2450 and AWST/AWDT are now used instead of the former CST, CWST, and WST.
2451 This change does not affect UT offsets, only time zone abbreviations.
2452 (Thanks to Rich Tibbett and many others.)
2454 Asia/Novokuznetsk shifts from NOVT to KRAT (remaining on UT +07)
2455 effective 2014-10-26 at 02:00 local time.
2457 The time zone abbreviation for Xinjiang Time (observed in Ürümqi)
2458 has been changed from URUT to XJT. (Thanks to Luther Ma.)
2460 Prefer MSK/MSD for Moscow time in Russia, even in other cities.
2461 Similarly, prefer EET/EEST for eastern European time in Russia.
2463 Change time zone abbreviations in (western) Samoa to use "ST" and
2464 "DT" suffixes, as this is more likely to match common practice.
2465 Prefix "W" to (western) Samoa time when its standard-time offset
2466 disagrees with that of American Samoa.
2468 America/Metlakatla now uses PST, not MeST, to abbreviate its time zone.
2470 Time zone abbreviations have been updated for Japan's two time
2471 zones used 1896-1937. JWST now stands for Western Standard
2472 Time, and JCST for Central Standard Time (formerly this was CJT).
2473 These abbreviations are now used for time in Korea, Taiwan,
2474 and Sakhalin while controlled by Japan.
2476 Changes affecting past timestamps
2478 China's five zones have been simplified to two, since the post-1970
2479 differences in the other three seem to have been imaginary. The
2480 zones Asia/Harbin, Asia/Chongqing, and Asia/Kashgar have been
2481 removed; backwards-compatibility links still work, albeit with
2482 different behaviors for timestamps before May 1980. Asia/Urumqi's
2483 1980 transition to UT +08 has been removed, so that it is now at
2484 +06 and not +08. (Thanks to Luther Ma and to Alois Treindl;
2485 Treindl sent helpful translations of two papers by Guo Qingsheng.)
2487 Some zones have been turned into links, when they differed from existing
2488 zones only for older UT offsets where data entries were likely invented.
2489 These changes affect UT offsets in pre-1970 timestamps only. This is
2490 similar to the change in release 2013e, except this time for western
2491 Africa. The affected zones are: Africa/Bamako, Africa/Banjul,
2492 Africa/Conakry, Africa/Dakar, Africa/Freetown, Africa/Lome,
2493 Africa/Nouakchott, Africa/Ouagadougou, Africa/Sao_Tome, and
2494 Atlantic/St_Helena. This also affects the backwards-compatibility
2495 link Africa/Timbuktu. (Thanks to Alan Barrett, Stephen Colebourne,
2496 Tim Parenti, and David Patte for reporting problems in earlier
2497 versions of this change.)
2499 Asia/Shanghai's pre-standard-time UT offset has been changed from
2500 8:05:57 to 8:05:43, the location of Xujiahui Observatory. Its
2501 transition to standard time has been changed from 1928 to 1901.
2503 Asia/Taipei switched to JWST on 1896-01-01, then to JST on 1937-10-01,
2504 then to CST on 1945-09-21 at 01:00, and did not observe DST in 1945.
2505 In 1946 it observed DST from 05-15 through 09-30; in 1947
2506 from 04-15 through 10-31; and in 1979 from 07-01 through 09-30.
2507 (Thanks to Yu-Cheng Chuang.)
2509 Asia/Riyadh's transition to standard time is now 1947-03-14, not 1950.
2511 Europe/Helsinki's 1942 fall-back transition was 10-04 at 01:00, not
2512 10-03 at 00:00. (Thanks to Konstantin Hyppönen.)
2514 Pacific/Pago_Pago has been changed from UT -11:30 to -11 for the
2515 period from 1911 to 1950.
2517 Pacific/Chatham has been changed to New Zealand standard time plus
2518 45 minutes for the period before 1957, reflecting a 1956 remark in
2519 the New Zealand parliament.
2521 Europe/Budapest has several pre-1946 corrections: in 1918 the transition
2522 out of DST was on 09-16, not 09-29; in 1919 it was on 11-24, not 09-15; in
2523 1945 it was on 11-01, not 11-03; in 1941 the transition to DST was 04-08
2524 not 04-06 at 02:00; and there was no DST in 1920.
2526 Africa/Accra is now assumed to have observed DST from 1920 through 1935.
2528 Time in Russia before 1927 or so has been corrected by a few seconds in
2529 the following zones: Europe/Moscow, Asia/Irkutsk, Asia/Tbilisi,
2530 Asia/Tashkent, Asia/Vladivostok, Asia/Yekaterinburg, Europe/Helsinki, and
2531 Europe/Riga. Also, Moscow's location has been changed to its Kilometer 0
2532 point. (Thanks to Vladimir Karpinsky for the Moscow changes.)
2534 Changes affecting data format
2536 A new file 'zone1970.tab' supersedes 'zone.tab' in the installed data.
2537 The new file's extended format allows multiple country codes per zone.
2538 The older file is still installed but is deprecated; its format is
2539 not changing and it will still be distributed for a while, but new
2540 applications should use the new file.
2542 The new file format simplifies maintenance of obscure locations.
2543 To test this, it adds coverage for the Crozet Islands and the
2544 Scattered Islands. (Thanks to Tobias Conradi and Antoine Leca.)
2546 The file 'iso3166.tab' is planned to switch from ASCII to UTF-8.
2547 It is still ASCII now, but commentary about the switch has been added.
2548 The new file 'zone1970.tab' already uses UTF-8.
2550 Changes affecting code
2552 'localtime', 'mktime', etc. now use much less stack space if ALL_STATE
2553 is defined. (Thanks to Elliott Hughes for reporting the problem.)
2555 'zic' no longer mishandles input when ignoring case in locales that
2556 are not compatible with English, e.g., unibyte Turkish locales when
2557 compiled with HAVE_GETTEXT.
2559 Error diagnostics of 'zic' and 'yearistype' have been reworded so that
2560 they no longer use ASCII '-' as if it were a dash.
2562 'zic' now rejects output file names that contain '.' or '..' components.
2563 (Thanks to Tim Parenti for reporting the problem.)
2565 'zic -v' now warns about output file names that do not follow
2566 POSIX rules, or that contain a digit or '.'. (Thanks to Arthur
2567 David Olson for starting the ball rolling on this.)
2569 Some lint has been removed when using GCC_DEBUG_FLAGS with GCC 4.9.0.
2571 Changes affecting build procedure
2573 'zic' no longer links in localtime.o and asctime.o, as they're not needed.
2574 (Thanks to John Cochran.)
2576 Changes affecting documentation and commentary
2578 The 'Theory' file documents legacy names, the longstanding
2579 exceptions to the POSIX-inspired file name rules.
2581 The 'zic' documentation clarifies the role of time types when
2582 interpreting dates. (Thanks to Arthur David Olson.)
2584 Documentation and commentary now prefer UTF-8 to US-ASCII,
2585 allowing the use of proper accents in foreign words and names.
2586 Code and data have not changed because of this. (Thanks to
2587 Garrett Wollman, Ian Abbott, and Guy Harris for helping to debug
2590 Non-HTML documentation and commentary now use plain-text URLs instead of
2591 HTML insertions, and are more consistent about bracketing URLs when they
2592 are not already surrounded by white space. (Thanks to suggestions by
2595 There is new commentary about Xujiahui Observatory, the five time-zone
2596 project in China from 1918 to 1949, timekeeping in Japanese-occupied
2597 Shanghai, and Tibet Time in the 1950s. The sharp-eyed can spot the
2598 warlord Jin Shuren in the data.
2600 Commentary about the coverage of each Russian zone has been standardized.
2601 (Thanks to Tim Parenti.)
2603 There is new commentary about contemporary timekeeping in Ethiopia.
2605 Obsolete comments about a 2007 proposal for DST in Kuwait has been removed.
2607 There is new commentary about time in Poland in 1919.
2609 Proper credit has been given to DST inventor George Vernon Hudson.
2611 Commentary about time in Metlakatla, AK and Resolute, NU has been
2612 improved, with a new source for the former.
2614 In zone.tab, Pacific/Easter no longer mentions Salas y Gómez, as it
2617 Commentary about permanent Antarctic bases has been updated.
2619 Several typos have been corrected. (Thanks to Tim Parenti for
2620 contributing some of these fixes.)
2622 tz-link.htm now mentions the JavaScript libraries Moment Timezone,
2623 TimezoneJS.Date, Walltime-js, and Timezone. (Thanks to a heads-up
2624 from Matt Johnson.) Also, it mentions the Go 'latlong' package.
2625 (Thanks to a heads-up from Dirkjan Ochtman.)
2627 The files usno1988, usno1989, usno1989a, usno1995, usno1997, and usno1998
2628 have been removed. These obsolescent US Naval Observatory entries were no
2629 longer helpful for maintenance. (Thanks to Tim Parenti for the suggestion.)
2632 Release 2014e - 2014-06-12 21:53:52 -0700
2634 Changes affecting near-future timestamps
2636 Egypt's 2014 Ramadan-based transitions are June 26 and July 31 at 24:00.
2637 (Thanks to Imed Chihi.) Guess that from 2015 on Egypt will temporarily
2638 switch to standard time at 24:00 the last Thursday before Ramadan, and
2639 back to DST at 00:00 the first Friday after Ramadan.
2641 Similarly, Morocco's are June 28 at 03:00 and August 2 at 02:00. (Thanks
2642 to Milamber Space Network.) Guess that from 2015 on Morocco will
2643 temporarily switch to standard time at 03:00 the last Saturday before
2644 Ramadan, and back to DST at 02:00 the first Saturday after Ramadan.
2646 Changes affecting past timestamps
2648 The abbreviation "MSM" (Moscow Midsummer Time) is now used instead of
2649 "MSD" for Moscow's double daylight time in summer 1921. Also, a typo
2650 "VLASST" has been repaired to be "VLAST" for Vladivostok summer time
2651 in 1991. (Thanks to Hank W. for reporting the problems.)
2653 Changes affecting commentary
2655 tz-link.htm now cites RFC 7265 for jCal, mentions PTP and the
2656 draft CalDAV extension, updates URLs for TSP, TZInfo, IATA, and
2657 removes stale pointers to World Time Explorer and WORLDTIME.
2660 Release 2014d - 2014-05-27 21:34:40 -0700
2662 Changes affecting code
2664 zic no longer generates files containing timestamps before the Big Bang.
2665 This works around GNOME glib bug 878
2666 <https://gitlab.gnome.org/GNOME/glib/issues/878>
2667 (Thanks to Leonardo Chiquitto for reporting the bug, and to
2668 Arthur David Olson and James Cloos for suggesting improvements to the fix.)
2670 Changes affecting documentation
2672 tz-link.htm now mentions GNOME.
2675 Release 2014c - 2014-05-13 07:44:13 -0700
2677 Changes affecting near-future timestamps
2679 Egypt observes DST starting 2014-05-15 at 24:00.
2680 (Thanks to Ahmad El-Dardiry and Gunther Vermier.)
2681 Details have not been announced, except that DST will not be observed
2682 during Ramadan. Guess that DST will stop during the same Ramadan dates as
2683 Morocco, and that Egypt's future spring and fall transitions will be the
2684 same as 2010 when it last observed DST, namely April's last Friday at
2685 00:00 to September's last Thursday at 23:00 standard time. Also, guess
2686 that Ramadan transitions will be at 00:00 standard time.
2688 Changes affecting code
2690 zic now generates transitions for minimum time values, eliminating guesswork
2691 when handling low-valued timestamps. (Thanks to Arthur David Olson.)
2693 Port to Cygwin sans glibc. (Thanks to Arthur David Olson.)
2695 Changes affecting commentary and documentation
2697 Remove now-confusing comment about Jordan. (Thanks to Oleksii Nochovnyi.)
2700 Release 2014b - 2014-03-24 21:28:50 -0700
2702 Changes affecting near-future timestamps
2704 Crimea switches to Moscow time on 2014-03-30 at 02:00 local time.
2705 (Thanks to Alexander Krivenyshev.) Move its zone.tab entry from UA to RU.
2707 New entry for Troll station, Antarctica. (Thanks to Paul-Inge Flakstad and
2708 Bengt-Inge Larsson.) This is currently an approximation; a better version
2709 will require the zic and localtime fixes mentioned below, and the plan is
2710 to wait for a while until at least the zic fixes propagate.
2712 Changes affecting code
2714 'zic' and 'localtime' no longer reject locations needing four transitions
2715 per year for the foreseeable future. (Thanks to Andrew Main (Zefram).)
2716 Also, 'zic' avoids some unlikely failures due to integer overflow.
2718 Changes affecting build procedure
2720 'make check' now detects Rule lines defined but never used.
2721 The NZAQ rules, an instance of this problem, have been removed.
2723 Changes affecting commentary and documentation
2725 Fix Tuesday/Thursday typo in description of time in Israel.
2726 (Thanks to Bert Katz via Pavel Kharitonov and Mike Frysinger.)
2728 Microsoft Windows 8.1 doesn't support tz database names. (Thanks
2729 to Donald MacQueen.) Instead, the Microsoft Windows Store app
2730 library supports them.
2732 Add comments about Johnston Island time in the 1960s.
2733 (Thanks to Lyle McElhaney.)
2735 Morocco's 2014 DST start will be as predicted.
2736 (Thanks to Sebastien Willemijns.)
2739 Release 2014a - 2014-03-07 23:30:29 -0800
2741 Changes affecting near-future timestamps
2743 Turkey begins DST on 2014-03-31, not 03-30. (Thanks to Faruk Pasin for
2744 the heads-up, and to Tim Parenti for simplifying the update.)
2746 Changes affecting past timestamps
2748 Fiji ended DST on 2014-01-19 at 02:00, not the previously-scheduled 03:00.
2749 (Thanks to Steffen Thorsen.)
2751 Ukraine switched from Moscow to Eastern European time on 1990-07-01
2752 (not 1992-01-01), and observed DST during the entire next winter.
2753 (Thanks to Vladimir in Moscow via Alois Treindl.)
2755 In 1988 Israel observed DST from 04-10 to 09-04, not 04-09 to 09-03.
2756 (Thanks to Avigdor Finkelstein.)
2758 Changes affecting code
2760 A uninitialized-storage bug in 'localtime' has been fixed.
2761 (Thanks to Logan Chien.)
2763 Changes affecting the build procedure
2765 The settings for 'make check_web' now default to Ubuntu 13.10.
2767 Changes affecting commentary and documentation
2769 The boundary of the US Pacific time zone is given more accurately.
2770 (Thanks to Alan Mintz.)
2772 Chile's 2014 DST will be as predicted. (Thanks to José Miguel Garrido.)
2774 Paraguay's 2014 DST will be as predicted. (Thanks to Carlos Raúl Perasso.)
2776 Better descriptions of countries with same time zone history as
2777 Trinidad and Tobago since 1970. (Thanks to Alan Barrett for suggestion.)
2779 Several changes affect tz-link.htm, the main web page.
2781 Mention Time.is (thanks to Even Scharning) and WX-now (thanks to
2784 Mention xCal (Internet RFC 6321) and jCal.
2786 Microsoft has some support for tz database names.
2788 CLDR data formats include both XML and JSON.
2790 Mention Maggiolo's map of solar vs standard time.
2791 (Thanks to Arthur David Olson.)
2793 Mention TZ4Net. (Thanks to Matt Johnson.)
2795 Mention the timezone-olson Haskell package.
2797 Mention zeitverschiebung.net. (Thanks to Martin Jäger.)
2799 Remove moribund links to daylight-savings-time.info and to
2800 Simple Timer + Clocks.
2802 Update two links. (Thanks to Oscar van Vlijmen.)
2804 Fix some formatting glitches, e.g., remove random newlines from
2805 abbr elements' title attributes.
2808 Release 2013i - 2013-12-17 07:25:23 -0800
2810 Changes affecting near-future timestamps:
2812 Jordan switches back to standard time at 00:00 on December 20, 2013.
2813 The 2006-2011 transition schedule is planned to resume in 2014.
2814 (Thanks to Steffen Thorsen.)
2816 Changes affecting past timestamps:
2818 In 2004, Cuba began DST on March 28, not April 4.
2819 (Thanks to Steffen Thorsen.)
2821 Changes affecting code
2823 The compile-time flag NOSOLAR has been removed, as nowadays the
2824 benefit of slightly shrinking runtime table size is outweighed by the
2825 cost of disallowing potential future updates that exceed old limits.
2827 Changes affecting documentation and commentary
2829 The files solar87, solar88, and solar89 are no longer distributed.
2830 They were a negative experiment - that is, a demonstration that
2831 tz data can represent solar time only with some difficulty and error.
2832 Their presence in the distribution caused confusion, as Riyadh
2833 civil time was generally not solar time in those years.
2835 tz-link.htm now mentions Noda Time. (Thanks to Matt Johnson.)
2838 Release 2013h - 2013-10-25 15:32:32 -0700
2840 Changes affecting current and future timestamps:
2842 Libya has switched its UT offset back to +02 without DST, instead
2843 of +01 with DST. (Thanks to Even Scharning.)
2845 Western Sahara (Africa/El_Aaiun) uses Morocco's DST rules.
2846 (Thanks to Gwillim Law.)
2848 Changes affecting future timestamps:
2850 Acre and (we guess) western Amazonas will switch from UT -04 to -05
2851 on 2013-11-10. This affects America/Rio_Branco and America/Eirunepe.
2852 (Thanks to Steffen Thorsen.)
2854 Add entries for DST transitions in Morocco in the year 2038.
2855 This avoids some year-2038 glitches introduced in 2013g.
2856 (Thanks to Yoshito Umaoka for reporting the problem.)
2858 Changes affecting API
2860 The 'tzselect' command no longer requires the 'select' command,
2861 and should now work with /bin/sh on more platforms. It also works
2862 around a bug in BusyBox awk before version 1.21.0. (Thanks to
2863 Patrick 'P. J.' McDermott and Alan Barrett.)
2865 Changes affecting code
2867 Fix localtime overflow bugs with 32-bit unsigned time_t.
2869 zdump no longer assumes sscanf returns maximal values on overflow.
2871 Changes affecting the build procedure
2873 The builder can specify which programs to use, if any, instead of
2874 'ar' and 'ranlib', and libtz.a is now built locally before being
2875 installed. (Thanks to Michael Forney.)
2877 A dependency typo in the 'zdump' rule has been fixed.
2878 (Thanks to Andrew Paprocki.)
2880 The Makefile has been simplified by assuming that 'mkdir -p' and 'cp -f'
2881 work as specified by POSIX.2-1992 or later; this is portable nowadays.
2883 'make clean' no longer removes 'leapseconds', since it's
2884 host-independent and is part of the distribution.
2886 The unused makefile macros TZCSRCS, TZDSRCS, DATESRCS have been removed.
2888 Changes affecting documentation and commentary
2890 tz-link.htm now mentions TC TIMEZONE's draft time zone service protocol
2891 (thanks to Mike Douglass) and TimezoneJS.Date (thanks to Jim Fehrle).
2893 Update URLs in tz-link page. Add URLs for Microsoft Windows, since
2894 8.1 introduces tz support. Remove URLs for Tru64 and UnixWare (no
2895 longer maintained) and for old advisories. SOFA now does C.
2897 Release 2013g - 2013-09-30 21:08:26 -0700
2899 Changes affecting current and near-future timestamps
2901 Morocco now observes DST from the last Sunday in March to the last
2902 Sunday in October, not April to September respectively. (Thanks
2903 to Steffen Thorsen.)
2905 Changes affecting 'zic'
2907 'zic' now runs on platforms that lack both hard links and symlinks.
2908 (Thanks to Theo Veenker for reporting the problem, for MinGW.)
2909 Also, fix some bugs on platforms that lack hard links but have symlinks.
2911 'zic -v' again warns that Asia/Tehran has no POSIX environment variable
2912 to predict the far future, fixing a bug introduced in 2013e.
2914 Changes affecting the build procedure
2916 The 'leapseconds' file is again put into the tzdata tarball.
2917 Also, 'leapseconds.awk', so tzdata is self-contained. (Thanks to
2918 Matt Burgess and Ian Abbott.) The timestamps of these and other
2919 dependent files in tarballs are adjusted more consistently.
2921 Changes affecting documentation and commentary
2923 The README file is now part of the data tarball as well as the code.
2924 It now states that files are public domain unless otherwise specified.
2925 (Thanks to Andrew Main (Zefram) for asking for clarifications.)
2926 Its details about the 1989 release moved to a place of honor near
2930 Release 2013f - 2013-09-24 23:37:36 -0700
2932 Changes affecting near-future timestamps
2934 Tocantins will very likely not observe DST starting this spring.
2935 (Thanks to Steffen Thorsen.)
2937 Jordan will likely stay at UT +03 indefinitely, and will not fall
2940 Palestine will fall back at 00:00, not 01:00. (Thanks to Steffen Thorsen.)
2942 Changes affecting API
2944 The types of the global variables 'timezone' and 'altzone' (if present)
2945 have been changed back to 'long'. This is required for 'timezone'
2946 by POSIX, and for 'altzone' by common practice, e.g., Solaris 11.
2947 These variables were originally 'long' in the tz code, but were
2948 mistakenly changed to 'time_t' in 1987; nobody reported the
2949 incompatibility until now. The difference matters on x32, where
2950 'long' is 32 bits and 'time_t' is 64. (Thanks to Elliott Hughes.)
2952 Changes affecting the build procedure
2954 Avoid long strings in leapseconds.awk to work around a mawk bug.
2955 (Thanks to Cyril Baurand.)
2957 Changes affecting documentation and commentary
2959 New file 'NEWS' that contains release notes like this one.
2961 Paraguay's law does not specify DST transition time; 00:00 is customary.
2962 (Thanks to Waldemar Villamayor-Venialbo.)
2964 Minor capitalization fixes.
2966 Changes affecting version-control only
2968 The experimental GitHub repository now contains annotated and
2969 signed tags for recent releases, e.g., '2013e' for Release 2013e.
2970 Releases are tagged starting with 2012e; earlier releases were
2971 done differently, and tags would either not have a simple name or
2972 not exactly match what was released.
2974 'make set-timestamps' is now simpler and a bit more portable.
2977 Release 2013e - 2013-09-19 23:50:04 -0700
2979 Changes affecting near-future timestamps
2981 This year Fiji will start DST on October 27, not October 20.
2982 (Thanks to David Wheeler for the heads-up.) For now, guess that
2983 Fiji will continue to spring forward the Sunday before the fourth
2986 Changes affecting current and future time zone abbreviations
2988 Use WIB/WITA/WIT rather than WIT/CIT/EIT for alphabetic Indonesian
2989 time zone abbreviations since 1932. (Thanks to George Ziegler,
2990 Priyadi Iman Nurcahyo, Zakaria, Jason Grimes, Martin Pitt, and
2991 Benny Lin.) This affects Asia/Dili, Asia/Jakarta, Asia/Jayapura,
2992 Asia/Makassar, and Asia/Pontianak.
2994 Use ART (UT -03, standard time), rather than WARST (also -03, but
2995 daylight saving time) for San Luis, Argentina since 2009.
2997 Changes affecting Godthåb timestamps after 2037 if version mismatch
2999 Allow POSIX-like TZ strings where the transition time's hour can
3000 range from -167 through 167, instead of the POSIX-required 0
3001 through 24. E.g., TZ='FJT-12FJST,M10.3.1/146,M1.3.4/75' for the
3002 new Fiji rules. This is a more-compact way to represent
3003 far-future timestamps for America/Godthab, America/Santiago,
3004 Antarctica/Palmer, Asia/Gaza, Asia/Hebron, Asia/Jerusalem,
3005 Pacific/Easter, and Pacific/Fiji. Other zones are unaffected by
3006 this change. (Derived from a suggestion by Arthur David Olson.)
3008 Allow POSIX-like TZ strings where daylight saving time is in
3009 effect all year. E.g., TZ='WART4WARST,J1/0,J365/25' for Western
3010 Argentina Summer Time all year. This supports a more-compact way
3011 to represent the 2013d data for America/Argentina/San_Luis.
3012 Because of the change for San Luis noted above this change does not
3013 affect the current data. (Thanks to Andrew Main (Zefram) for
3014 suggestions that improved this change.)
3016 Where these two TZ changes take effect, there is a minor extension
3017 to the tz file format in that it allows new values for the
3018 embedded TZ-format string, and the tz file format version number
3019 has therefore been increased from 2 to 3 as a precaution.
3020 Version-2-based client code should continue to work as before for
3021 all timestamps before 2038. Existing version-2-based client code
3022 (tzcode, GNU/Linux, Solaris) has been tested on version-3-format
3023 files, and typically works in practice even for timestamps after
3024 2037; the only known exception is America/Godthab.
3026 Changes affecting timestamps before 1970
3028 Pacific/Johnston is now a link to Pacific/Honolulu. This corrects
3029 some errors before 1947.
3031 Some zones have been turned into links, when they differ from existing
3032 zones only in older data entries that were likely invented or that
3033 differ only in LMT or transitions from LMT. These changes affect
3034 only timestamps before 1943. The affected zones are:
3035 Africa/Juba, America/Anguilla, America/Aruba, America/Dominica,
3036 America/Grenada, America/Guadeloupe, America/Marigot,
3037 America/Montserrat, America/St_Barthelemy, America/St_Kitts,
3038 America/St_Lucia, America/St_Thomas, America/St_Vincent,
3039 America/Tortola, and Europe/Vaduz. (Thanks to Alois Treindl for
3040 confirming that the old Europe/Vaduz zone was wrong and the new
3041 link is better for WWII-era times.)
3043 Change Kingston Mean Time from -5:07:12 to -5:07:11. This affects
3044 America/Cayman, America/Jamaica and America/Grand_Turk timestamps
3047 Change the UT offset of Bern Mean Time from 0:29:44 to 0:29:46.
3048 This affects Europe/Zurich timestamps from 1853 to 1894. (Thanks
3051 Change the date of the circa-1850 Zurich transition from 1849-09-12
3052 to 1853-07-16, overriding Shanks with data from Messerli about
3053 postal and telegraph time in Switzerland.
3055 Changes affecting time zone abbreviations before 1970
3057 For Asia/Jakarta, use BMT (not JMT) for mean time from 1923 to 1932,
3058 as Jakarta was called Batavia back then.
3060 Changes affecting API
3062 The 'zic' command now outputs a dummy transition when far-future
3063 data can't be summarized using a TZ string, and uses a 402-year
3064 window rather than a 400-year window. For the current data, this
3065 affects only the Asia/Tehran file. It does not affect any of the
3066 timestamps that this file represents, so zdump outputs the same
3067 information as before. (Thanks to Andrew Main (Zefram).)
3069 The 'date' command has a new '-r' option, which lets you specify
3070 the integer time to display, a la FreeBSD.
3072 The 'tzselect' command has two new options '-c' and '-n', which lets you
3073 select a zone based on latitude and longitude.
3075 The 'zic' command's '-v' option now warns about constructs that
3076 require the new version-3 binary file format. (Thanks to Arthur
3077 David Olson for the suggestion.)
3079 Support for floating-point time_t has been removed.
3080 It was always dicey, and POSIX no longer requires it.
3081 (Thanks to Eric Blake for suggesting to the POSIX committee to
3082 remove it, and thanks to Alan Barrett, Clive D.W. Feather, Andy
3083 Heninger, Arthur David Olson, and Alois Treindl, for reporting
3084 bugs and elucidating some of the corners of the old floating-point
3087 The signatures of 'offtime', 'timeoff', and 'gtime' have been
3088 changed back to the old practice of using 'long' to represent UT
3089 offsets. This had been inadvertently and mistakenly changed to
3090 'int_fast32_t'. (Thanks to Christos Zoulas.)
3092 The code avoids undefined behavior on integer overflow in some
3093 more places, including gmtime, localtime, mktime and zdump.
3095 Changes affecting the zdump utility
3097 zdump now outputs "UT" when referring to Universal Time, not "UTC".
3098 "UTC" does not make sense for timestamps that predate the introduction
3099 of UTC, whereas "UT", a more-generic term, does. (Thanks to Steve Allen
3100 for clarifying UT vs UTC.)
3102 Data changes affecting behavior of tzselect and similar programs
3104 Country code BQ is now called the more-common name "Caribbean Netherlands"
3105 rather than the more-official "Bonaire, St Eustatius & Saba".
3107 Remove from zone.tab the names America/Montreal, America/Shiprock,
3108 and Antarctica/South_Pole, as they are equivalent to existing
3109 same-country-code zones for post-1970 timestamps. The data entries for
3110 these names are unchanged, so the names continue to work as before.
3112 Changes affecting code internals
3114 zic -c now runs way faster on 64-bit hosts when given large numbers.
3116 zic now uses vfprintf to avoid allocating and freeing some memory.
3118 tzselect now computes the list of continents from the data,
3119 rather than have it hard-coded.
3121 Minor changes pacify GCC 4.7.3 and GCC 4.8.1.
3123 Changes affecting the build procedure
3125 The 'leapseconds' file is now generated automatically from a
3126 new file 'leap-seconds.list', which is a copy of
3127 <ftp://ftp.nist.gov/pub/time/leap-seconds.list>
3128 A new source file 'leapseconds.awk' implements this.
3129 The goal is simplification of the future maintenance of 'leapseconds'.
3131 When building the 'posix' or 'right' subdirectories, if the
3132 subdirectory would be a copy of the default subdirectory, it is
3133 now made a symbolic link if that is supported. This saves about
3134 2 MB of file system space.
3136 The links America/Shiprock and Antarctica/South_Pole have been
3137 moved to the 'backward' file. This affects only nondefault builds
3138 that omit 'backward'.
3140 Changes affecting version-control only
3142 .gitignore now ignores 'date'.
3144 Changes affecting documentation and commentary
3146 Changes to the 'tzfile' man page
3148 It now mentions that the binary file format may be extended in
3149 future versions by appending data.
3151 It now refers to the 'zdump' and 'zic' man pages.
3153 Changes to the 'zic' man page
3155 It lists conditions that elicit a warning with '-v'.
3157 It says that the behavior is unspecified when duplicate names
3158 are given, or if the source of one link is the target of another.
3160 Its examples are updated to match the latest data.
3162 The definition of white space has been clarified slightly.
3163 (Thanks to Michael Deckers.)
3165 Changes to the 'Theory' file
3167 There is a new section about the accuracy of the tz database,
3168 describing the many ways that errors can creep in, and
3169 explaining why so many of the pre-1970 timestamps are wrong or
3170 misleading (thanks to Steve Allen, Lester Caine, and Garrett
3171 Wollman for discussions that contributed to this).
3173 The 'Theory' file describes LMT better (this follows a
3174 suggestion by Guy Harris).
3176 It refers to the 2013 edition of POSIX rather than the 2004 edition.
3178 It's mentioned that excluding 'backward' should not affect the
3179 other data, and it suggests at least one zone.tab name per
3180 inhabited country (thanks to Stephen Colebourne).
3182 Some longstanding restrictions on names are documented, e.g.,
3183 'America/New_York' precludes 'America/New_York/Bronx'.
3185 It gives more reasons for the 1970 cutoff.
3187 It now mentions which time_t variants are supported, such as
3188 signed integer time_t. (Thanks to Paul Goyette for reporting
3189 typos in an experimental version of this change.)
3191 (Thanks to Philip Newton for correcting typos in these changes.)
3193 Documentation and commentary is more careful to distinguish UT in
3194 general from UTC in particular. (Thanks to Steve Allen.)
3196 Add a better source for the Zurich 1894 transition.
3197 (Thanks to Pierre-Yves Berger.)
3199 Update shapefile citations in tz-link.htm. (Thanks to Guy Harris.)
3202 Release 2013d - 2013-07-05 07:38:01 -0700
3204 Changes affecting future timestamps:
3206 Morocco's midsummer transitions this year are July 7 and August 10,
3207 not July 9 and August 8. (Thanks to Andrew Paprocki.)
3209 Israel now falls back on the last Sunday of October.
3210 (Thanks to Ephraim Silverberg.)
3212 Changes affecting past timestamps:
3214 Specify Jerusalem's location more precisely; this changes the pre-1880
3217 Changing affecting metadata only:
3219 Fix typos in the entries for country codes BQ and SX.
3221 Changes affecting code:
3223 Rework the code to fix a bug with handling Australia/Macquarie on
3224 32-bit hosts (thanks to Arthur David Olson).
3226 Port to platforms like NetBSD, where time_t can be wider than long.
3228 Add support for testing time_t types other than the system's.
3229 Run 'make check_time_t_alternatives' to try this out.
3230 Currently, the tests fail for unsigned time_t;
3231 this should get fixed at some point.
3233 Changes affecting documentation and commentary:
3235 Deemphasize the significance of national borders.
3237 Update the zdump man page.
3239 Remove obsolete NOID comment (thanks to Denis Excoffier).
3241 Update several URLs and comments in the web pages.
3243 Spelling fixes (thanks to Kevin Lyda and Jonathan Leffler).
3245 Update URL for CLDR Zone->Tzid table (thanks to Yoshito Umaoka).
3248 Release 2013c - 2013-04-19 16:17:40 -0700
3250 Changes affecting current and future timestamps:
3252 Palestine observed DST starting March 29, 2013. (Thanks to
3253 Steffen Thorsen.) From 2013 on, Gaza and Hebron both observe DST,
3254 with the predicted rules being the last Thursday in March at 24:00
3255 to the first Friday on or after September 21 at 01:00.
3257 Assume that the recent change to Paraguay's DST rules is permanent,
3258 by moving the end of DST to the 4th Sunday in March every year.
3259 (Thanks to Carlos Raúl Perasso.)
3261 Changes affecting past timestamps:
3263 Fix some historical data for Palestine to agree with that of
3264 timeanddate.com, as follows:
3266 The spring 2008 change in Gaza and Hebron was on 00:00 Mar 28, not
3269 The fall 2009 change in Gaza and Hebron on Sep 4 was at 01:00, not
3272 The spring 2010 change in Hebron was 00:00 Mar 26, not 00:01 Mar 27.
3274 The spring 2011 change in Gaza was 00:01 Apr 1, not 12:01 Apr 2.
3276 The spring 2011 change in Hebron on Apr 1 was at 00:01, not 12:01.
3278 The fall 2011 change in Hebron on Sep 30 was at 00:00, not 03:00.
3280 Fix times of habitation for Macquarie to agree with the Tasmania
3281 Parks & Wildlife Service history, which indicates that permanent
3282 habitation was 1899-1919 and 1948 on.
3284 Changing affecting metadata only:
3286 Macquarie Island is politically part of Australia, not Antarctica.
3287 (Thanks to Tobias Conradi.)
3289 Sort Macquarie more-consistently with other parts of Australia.
3290 (Thanks to Tim Parenti.)
3293 Release 2013b - 2013-03-10 22:33:40 -0700
3295 Changes affecting current and future timestamps:
3297 Haiti uses US daylight-saving rules this year, and presumably future years.
3298 This changes timestamps starting today. (Thanks to Steffen Thorsen.)
3300 Paraguay will end DST on March 24 this year.
3301 (Thanks to Steffen Thorsen.) For now, assume it's just this year.
3303 Morocco does not observe DST during Ramadan;
3304 try to predict Ramadan in Morocco as best we can.
3305 (Thanks to Erik Homoet for the heads-up.)
3307 Changes affecting commentary:
3309 Update URLs in tz-link page. Add URLs for webOS, BB10, iOS.
3310 Update URL for Solaris. Mention Internet RFC 6557.
3311 Update Internet RFCs 2445->5545, 2822->5322.
3312 Switch from FTP to HTTP for Internet RFCs.
3315 Release 2013a - 2013-02-27 09:20:35 -0800
3317 Change affecting binary data format:
3319 The zone offset at the end of version-2-format zone files is now
3320 allowed to be 24:00, as per POSIX.1-2008. (Thanks to Arthur David Olson.)
3322 Changes affecting current and future timestamps:
3324 Chile's 2013 rules, and we guess rules for 2014 and later, will be
3325 the same as 2012, namely Apr Sun>=23 03:00 UTC to Sep Sun>=2 04:00 UTC.
3326 (Thanks to Steffen Thorsen and Robert Elz.)
3328 New Zones Asia/Khandyga, Asia/Ust-Nera, Europe/Busingen.
3329 (Thanks to Tobias Conradi and Arthur David Olson.)
3331 Many changes affect historical timestamps before 1940.
3332 These were deduced from: Milne J. Civil time. Geogr J. 1899
3333 Feb;13(2):173-94 <https://www.jstor.org/stable/1774359>.
3335 Changes affecting the code:
3337 Fix zic bug that mishandled Egypt's 2010 changes (this also affected
3338 the data). (Thanks to Arthur David Olson.)
3340 Fix localtime bug when time_t is unsigned and data files were generated
3341 by a signed time_t system. (Thanks to Doug Bailey for reporting and
3342 to Arthur David Olson for fixing.)
3344 Allow the email address for bug reports to be set by the packager.
3345 The default is tz@iana.org, as before. (Thanks to Joseph S. Myers.)
3347 Update HTML checking to be compatible with Ubuntu 12.10.
3349 Check that files are a safe subset of ASCII. At some point we may
3350 relax this requirement to a safe subset of UTF-8. Without the
3351 check, some non-UTF-8 encodings were leaking into the distribution.
3355 Restore a comment about copyright notices that was inadvertently deleted.
3356 (Thanks to Arthur David Olson.)
3358 Improve the commentary about which districts observe what times
3359 in Russia. (Thanks to Oscar van Vlijmen and Arthur David Olson.)
3361 Add web page links to tz.js.
3363 Add "Run by the Monkeys" to tz-art. (Thanks to Arthur David Olson.)
3366 Release 2012j - 2012-11-12 18:34:49 -0800
3368 Libya moved to CET this weekend, but with DST planned next year.
3369 (Thanks to Even Scharning, Steffen Thorsen, and Tim Parenti.)
3371 Signatures now have the extension .asc, not .sign, as that's more
3372 standard. (Thanks to Phil Pennock.)
3374 The output of 'zdump --version', and of 'zic --version', now
3375 uses a format that is more typical for --version.
3376 (Thanks to Joseph S. Myers.)
3378 The output of 'tzselect --help', 'zdump --help', and 'zic --help'
3379 now uses tz@iana.org rather than the old elsie address.
3381 zic -v now complains about abbreviations that are less than 3
3382 or more than 6 characters, as per Posix. Formerly, it checked
3383 for abbreviations that were more than 3.
3385 'make public' no longer puts its temporary directory under /tmp,
3386 and uses the just-built zic rather than the system zic.
3388 Various fixes to documentation and commentary.
3391 Release 2012i - 2012-11-03 12:57:09 -0700
3393 Cuba switches from DST tomorrow at 01:00. (Thanks to Steffen Thorsen.)
3395 Linker flags can now be specified via LDFLAGS.
3396 AWK now defaults to 'awk', not 'nawk'.
3397 The shell in tzselect now defaults to /bin/bash, but this can
3398 be overridden by specifying KSHELL.
3399 The main web page now mentions the unofficial GitHub repository.
3400 (Thanks to Mike Frysinger.)
3402 Tarball signatures can now be built by running 'make signatures'.
3403 There are also new makefile rules 'tarballs', 'check_public', and
3404 separate makefile rules for each tarball and signature file.
3405 A few makefile rules are now more portable to strict POSIX.
3407 The main web page now lists the canonical IANA URL.
3410 Release 2012h - 2012-10-26 22:49:10 -0700
3412 Bahia no longer has DST. (Thanks to Kelley Cook.)
3414 Tocantins has DST. (Thanks to Rodrigo Severo.)
3416 Israel has new DST rules next year. (Thanks to Ephraim Silverberg.)
3418 Jordan stays on DST this winter. (Thanks to Steffen Thorsen.)
3422 More C modernization, except that at Arthur David Olson's suggestion
3423 the instances of 'register' were kept.
3426 Release 2012g - 2012-10-17 20:59:45 -0700
3428 Samoa fall 2012 and later. (Thanks to Nicholas Pereira and Robert Elz.)
3430 Palestine fall 2012. (Thanks to Steffen Thorsen.)
3434 To attack the version-number problem, this release ships the file
3435 'Makefile' (which contains the release number) in both the tzcode and
3436 the tzdata tarballs. The two Makefiles are identical, and should be
3437 identical in any matching pair of tarballs, so it shouldn't matter
3438 which order you extract the tarballs. Perhaps we can come up with a
3439 better version-number scheme at some point; this scheme does have the
3440 virtue of not adding more files.
3443 Release 2012f - 2012-09-12 23:17:03 -0700
3445 * australasia (Pacific/Fiji): Fiji DST is October 21 through January
3446 20 this year. (Thanks to Steffen Thorsen.)
3449 Release 2012e - 2012-08-02 20:44:55 -0700
3451 * australasia (Pacific/Fakaofo): Tokelau is UT +13, not +14.
3452 (Thanks to Steffen Thorsen.)
3454 * Use a single version number for both code and data.
3456 * .gitignore: New file.
3458 * Remove trailing white space.
3461 Release code2012c-data2012d - 2012-07-19 16:35:33 -0700
3463 Changes for Morocco's timestamps, which take effect in a couple of
3464 hours, along with infrastructure changes to accommodate how the tz
3465 code and data are released on IANA.
3468 Release data2012c - 2012-03-27 12:17:25 -0400
3471 Summer time changes for Morocco (to start late April 2012)
3474 Changes for 2012 for Gaza & the West Bank (Hebron) and Syria
3477 Haiti following US/Canada rules for 2012 (and we're assuming,
3478 for now anyway, for the future).
3481 Release 2012b - 2012-03-02 12:29:15 +0700
3483 There is just one change to tzcode2012b (compared with 2012a):
3484 the Makefile that was accidentally included with 2012a has been
3485 replaced with the version that should have been there, which is
3486 identical with the previous version (from tzcode2011i).
3488 There are just two changes in tzdata2012b compared with 2012a.
3490 Most significantly, summer time in Cuba has been delayed 3 weeks
3491 (now starts April 1 rather than March 11). Since Mar 11 (the old start
3492 date, as listed in 2012a) is just a little over a week away, this
3495 Less importantly, an excess tab in one of the changes in zone.tab
3496 in 2012a has been removed.
3499 Release 2012a - 2012-03-01 18:28:10 +0700
3501 The changes in tzcode2012a (compared to the previous version, 2011i)
3502 are entirely to the README and tz-art.htm and tz-link.htm files, if
3503 none of those concern you, you can ignore the code update. The changes
3504 reflect the changed addresses for the mailing list and the code and
3505 data distribution points & methods (and a link to DateTime::TimeZone::Tzfile
3506 has been added to tz-link.htm).
3508 In tzdata2012a (compared to the previous release, which was 2011n)
3509 the major changes are:
3510 Chile 2011/2012 and 2012/2013 summer time date adjustments.
3511 Falkland Islands onto permanent summer time (we're assuming for the
3512 foreseeable future, though 2012 is all we're fairly certain of.)
3513 Armenia has abolished Summer Time.
3514 Tokelau jumped the International Date Line back last December
3515 (just the same as their near neighbour, Samoa).
3516 America/Creston is a new zone for a small area of British Columbia
3517 There will be a leapsecond 2012-06-30 23:59:60 UTC.
3519 Other minor changes are:
3520 Corrections to 1918 Canadian summer time end dates.
3521 Updated URL for UK time zone history (in comments)
3522 A few typos in Le Corre's list of free French place names (comments)
3525 Release data2011n - 2011-10-30 14:57:54 +0700
3527 There are three changes of note - most urgently, Cuba (America/Havana)
3528 has extended summer time by two weeks, now to end on Nov 13, rather than
3529 the (already past) Oct 30. Second, the Pridnestrovian Moldavian Republic
3530 (Europe/Tiraspol) decided not to split from the rest of Moldova after
3531 all, and consequently that zone has been removed (again) and reinstated
3532 in the "backward" file as a link to Europe/Chisinau. And third, the
3533 end date for Fiji's summer time this summer was moved forward from the
3534 earlier planned Feb 26, to Jan 22.
3536 Apart from that, Moldova (MD) returns to a single entry in zone.tab
3537 (and the incorrect syntax that was in the 2011m version of that file
3538 is so fixed - it would have been fixed in a different way had this
3539 change not happened - that's the "missing" sccs version id).
3542 Release data2011m - 2011-10-24 21:42:16 +0700
3544 In particular, the typos in comments in the data (2011-11-17 should have
3545 been 2011-10-17 as Alan Barrett noted, and spelling of Tiraspol that
3546 Tim Parenti noted) have been fixed, and the change for Ukraine has been
3547 made in all 4 Ukrainian zones, rather than just Kiev (again, thanks to
3548 Tim Parenti, and also Denys Gavrysh)
3550 In addition, I added Europe/Tiraspol to zone.tab.
3552 This time, all the files have new version numbers... (including the files
3553 otherwise unchanged in 2011m that were changed in 2011l but didn't get new
3554 version numbers there...)
3557 Release data2011l - 2011-10-10 11:15:43 +0700
3559 There are just 2 changes that cause different generated tzdata files from
3560 zic, to Asia/Hebron and Pacific/Fiji - the possible change for Bahia, Brazil
3561 is included, but commented out. Compared with the diff I sent out last week,
3562 this version also includes attributions for the sources for the changes
3563 (in much the same format as ado used, but the html tags have not been
3564 checked, verified, or used in any way at all, so if there are errors there,
3565 please let me know.)
3568 Release data2011k - 2011-09-20 17:54:03 -0400
3573 Release data2011j - 2011-09-12 09:22:49 -0400
3575 (contemporary changes for Samoa; past changes for Kenya, Uganda, and
3576 Tanzania); there are also two spelling corrections to comments in
3577 the australasia file (with thanks to Christos Zoulas).
3580 Release 2011i - 2011-08-29 05:56:32 -0400
3585 Release data2011h - 2011-06-15 18:41:48 -0400
3587 Russia and Curaçao changes
3590 Release 2011g - 2011-04-25 09:07:22 -0400
3592 update the rules for Egypt to reflect its abandonment of DST this year
3595 Release 2011f - 2011-04-06 17:14:53 -0400
3600 Release 2011e - 2011-03-31 16:04:38 -0400
3602 Morocco, Chile, and tz-link changes
3605 Release 2011d - 2011-03-14 09:18:01 -0400
3607 changes that impact present-day timestamps in Cuba, Samoa, and Turkey
3610 Release 2011c - 2011-03-07 09:30:09 -0500
3612 These do affect current timestamps in Chile and Annette Island, Canada.
3615 Release 2011b - 2011-02-07 08:44:50 -0500
3620 Release 2011a - 2011-01-24 10:30:16 -0500
3625 Release data2010o - 2010-11-01 09:18:23 -0400
3627 change to the end of DST in Fiji in 2011
3630 Release 2010n - 2010-10-25 08:19:17 -0400
3635 Release 2010m - 2010-09-27 09:24:48 -0400
3637 Hong Kong, Vostok, and zic.c changes
3640 Release 2010l - 2010-08-16 06:57:25 -0400
3645 Release 2010k - 2010-07-26 10:42:27 -0400
3650 Release 2010j - 2010-05-10 09:07:48 -0400
3652 changes for Bahía de Banderas and for version naming
3655 Release data2010i - 2010-04-16 18:50:45 -0400
3657 the end of DST in Morocco on 2010-08-08
3660 Release data2010h - 2010-04-05 09:58:56 -0400
3665 Release data2010g - 2010-03-24 11:14:53 -0400
3670 Release 2010f - 2010-03-22 09:45:46 -0400
3675 Release data2010e - 2010-03-08 14:24:27 -0500
3677 corrects the Dhaka bug found by Danvin Ruangchan
3680 Release data2010d - 2010-03-06 07:26:01 -0500
3685 Release 2010c - 2010-03-01 09:20:58 -0500
3687 changes including KRE's suggestion for earlier initialization of
3688 "goahead" and "goback" structure elements
3691 Release code2010a - 2010-02-16 10:40:04 -0500
3696 Release data2010b - 2010-01-20 12:37:01 -0500
3701 Release data2010a - 2010-01-18 08:30:04 -0500
3706 Release data2009u - 2009-12-26 08:32:28 -0500
3708 changes to DST in Bangladesh
3711 Release 2009t - 2009-12-21 13:24:27 -0500
3716 Release data2009s - 2009-11-14 10:26:32 -0500
3718 (cosmetic) Antarctica change and the DST-in-Fiji-in-2009-and-2010 change
3721 Release 2009r - 2009-11-09 10:10:31 -0500
3723 "antarctica" and "tz-link.htm" changes
3726 Release 2009q - 2009-11-02 09:12:40 -0500
3728 with two corrections as reported by Eric Muller and Philip Newton
3731 Release data2009p - 2009-10-23 15:05:27 -0400
3733 Argentina (including San Luis) changes (with the correction from
3737 Release data2009o - 2009-10-14 16:49:38 -0400
3739 Samoa (commentary only), Pakistan, and Bangladesh changes
3742 Release data2009n - 2009-09-22 15:13:38 -0400
3744 added commentary for Argentina and a change to the end of DST in
3748 Release data2009m - 2009-09-03 10:23:43 -0400
3750 Samoa and Palestine changes
3753 Release data2009l - 2009-08-14 09:13:07 -0400
3755 Samoa (comments only) and Egypt
3758 Release 2009k - 2009-07-20 09:46:08 -0400
3763 Release data2009j - 2009-06-15 06:43:59 -0400
3765 Bangladesh change (with a short turnaround since the DST change is
3769 Release 2009i - 2009-06-08 09:21:22 -0400
3771 updating for DST in Bangladesh this year
3774 Release 2009h - 2009-05-26 09:19:14 -0400
3779 Release data2009g - 2009-04-20 16:34:07 -0400
3784 Release data2009f - 2009-04-10 11:00:52 -0400
3786 correct DST in Pakistan
3789 Release 2009e - 2009-04-06 09:08:11 -0400
3794 Release 2009d - 2009-03-23 09:38:12 -0400
3796 Morocco, Tunisia, Argentina, and American Astronomical Society changes
3799 Release data2009c - 2009-03-16 09:47:51 -0400
3801 change to the start of Cuban DST
3804 Release 2009b - 2009-02-09 11:15:22 -0500
3809 Release 2009a - 2009-01-21 10:09:39 -0500
3814 Release data2008i - 2008-10-21 12:10:25 -0400
3816 southamerica and zone.tab files, with Argentina DST rule changes and
3817 United States zone reordering and recommenting
3820 Release 2008h - 2008-10-13 07:33:56 -0400
3825 Release 2008g - 2008-10-06 09:03:18 -0400
3827 Fix a broken HTML anchor and update Brazil's DST transitions;
3828 there's also a slight reordering of information in tz-art.htm.
3831 Release data2008f - 2008-09-09 22:33:26 -0400
3836 Release 2008e - 2008-07-28 14:11:17 -0400
3838 changes by Arthur David Olson and Jesper Nørgaard Welen
3841 Release data2008d - 2008-07-07 09:51:38 -0400
3843 changes by Arthur David Olson, Paul Eggert, and Rodrigo Severo
3846 Release data2008c - 2008-05-19 17:48:03 -0400
3848 Pakistan, Morocco, and Mongolia
3851 Release data2008b - 2008-03-24 08:30:59 -0400
3853 including renaming Asia/Calcutta to Asia/Kolkata, with a backward
3857 Release 2008a - 2008-03-08 05:42:16 -0500
3862 Release 2007k - 2007-12-31 10:25:22 -0500
3864 most importantly, changes to the "southamerica" file based on
3865 Argentina's readoption of daylight saving time
3868 Release 2007j - 2007-12-03 09:51:01 -0500
3870 1. eliminate the "P" (parameter) macro;
3872 2. the "noncontroversial" changes circulated on the time zone
3873 mailing list (less the changes to "logwtmp.c");
3875 3. eliminate "too many transition" errors when "min" is used in time
3878 4. changes by Paul Eggert (including updated information for Venezuela).
3881 Release data2007i - 2007-10-30 10:28:11 -0400
3883 changes for Cuba and Syria
3886 Release 2007h - 2007-10-01 10:05:51 -0400
3888 changes by Paul Eggert, as well as an updated link to the ICU
3889 project in tz-link.htm
3892 Release 2007g - 2007-08-20 10:47:59 -0400
3894 changes by Paul Eggert
3896 The "leapseconds" file has been updated to incorporate the most
3897 recent International Earth Rotation and Reference Systems Service
3900 There's an addition to tz-art.htm regarding the television show "Medium".
3903 Release 2007f - 2007-05-07 10:46:46 -0400
3905 changes by Paul Eggert (including Haiti, Turks and Caicos, and New
3908 changes to zic.c to allow hour values greater than 24 (along with
3909 Paul's improved time value overflow checking)
3912 Release 2007e - 2007-04-02 10:11:52 -0400
3914 Syria and Honduras changes by Paul Eggert
3916 zic.c variable renaming changes by Arthur David Olson
3919 Release 2007d - 2007-03-20 08:48:30 -0400
3921 changes by Paul Eggert
3923 the elimination of white space at the ends of lines
3926 Release 2007c - 2007-02-26 09:09:37 -0500
3928 changes by Paul Eggert
3931 Release 2007b - 2007-02-12 09:34:20 -0500
3933 Paul Eggert's proposed change to the quotation handling logic in zic.c.
3935 changes to the commentary in "leapseconds" reflecting the IERS
3936 announcement that there is to be no positive leap second at the end
3940 Release 2007a - 2007-01-08 12:28:29 -0500
3942 changes by Paul Eggert
3944 Derick Rethan's Asmara change
3946 Oscar van Vlijmen's Easter Island local mean time change
3948 symbolic link changes
3951 Release 2006p - 2006-11-27 08:54:27 -0500
3953 changes by Paul Eggert
3956 Release 2006o - 2006-11-06 09:18:07 -0500
3958 changes by Paul Eggert
3961 Release 2006n - 2006-10-10 11:32:06 -0400
3963 changes by Paul Eggert
3966 Release 2006m - 2006-10-02 15:32:35 -0400
3968 changes for Uruguay, Palestine, and Egypt by Paul Eggert
3970 (minimalist) changes to zic.8 to clarify "until" information
3973 Release data2006l - 2006-09-18 12:58:11 -0400
3975 Paul's best-effort work on this coming weekend's Egypt time change
3978 Release 2006k - 2006-08-28 12:19:09 -0400
3980 changes by Paul Eggert
3983 Release 2006j - 2006-08-21 09:56:32 -0400
3985 changes by Paul Eggert
3988 Release code2006i - 2006-08-07 12:30:55 -0400
3992 Ken Pizzini's conversion script
3995 Release code2006h - 2006-07-24 09:19:37 -0400
3997 adds public domain notices to four files
3999 includes a fix for transition times being off by a second
4001 adds a new recording to the "arts" file (information courtesy Colin Bowern)
4004 Release 2006g - 2006-05-08 17:18:09 -0400
4006 northamerica changes by Paul Eggert
4009 Release 2006f - 2006-05-01 11:46:00 -0400
4011 a missing version number problem is fixed (with thanks to Bradley
4012 White for catching the problem)
4015 Release 2006d - 2006-04-17 14:33:43 -0400
4017 changes by Paul Eggert
4019 added new items to tz-arts.htm that were found by Paul
4022 Release 2006c - 2006-04-03 10:09:32 -0400
4024 two sets of data changes by Paul Eggert
4026 a fencepost error fix in zic.c
4028 changes to zic.c and the "europe" file to minimize differences
4029 between output produced by the old 32-bit zic and the new 64-bit
4033 Release 2006b - 2006-02-20 10:08:18 -0500
4034 [tz32code2006b + tz64code2006b + tzdata2006b]
4038 All SCCS IDs were bumped to "8.1" for this release.
4041 Release 2006a - 2006-01-30 08:59:31 -0500
4043 changes by Paul Eggert (in particular, Indiana time zone moves)
4045 an addition to the zic manual page to describe how special-case
4046 transitions are handled
4049 Release 2005r - 2005-12-27 09:27:13 -0500
4051 Canadian changes by Paul Eggert
4053 They also add "<pre>" directives to time zone data files and reflect
4054 changes to warning message logic in "zdump.c" (but with calls to
4055 "gettext" kept unbundled at the suggestion of Ken Pizzini).
4058 Release 2005q - 2005-12-13 09:17:09 -0500
4060 Nothing earth-shaking here:
4061 1. Electronic mail addresses have been removed.
4062 2. Casts of the return value of exit have been removed.
4063 3. Casts of the argument of is.* macros have been added.
4064 4. Indentation in one section of zic.c has been fixed.
4065 5. References to dead URLs in the data files have been dealt with.
4068 Release 2005p - 2005-12-05 10:30:53 -0500
4070 "systemv", "tz-link.htm", and "zdump.c" changes
4071 (less the casts of arguments to the is* macros)
4074 Release 2005o - 2005-11-28 10:55:26 -0500
4076 Georgia, Cuba, Nicaragua, and Jordan changes by Paul Eggert
4078 zdump.c lint fixes by Arthur David Olson
4081 Release 2005n - 2005-10-03 09:44:09 -0400
4083 changes by Paul Eggert (both the Uruguay changes and the Kyrgyzstan
4087 Release 2005m - 2005-08-29 12:15:40 -0400
4089 changes by Paul Eggert (with a small tweak to the tz-art change)
4091 a declaration of an unused variable has been removed from zdump.c
4094 Release 2005l - 2005-08-22 12:06:39 -0400
4096 changes by Paul Eggert
4098 overflow/underflow checks by Arthur David Olson, minus changes to
4099 the "Theory" file about the pending addition of 64-bit data (I grow
4100 less confident of the changes being accepted with each passing day,
4101 and the changes no longer increase the data files nine-fold--there's
4102 less than a doubling in size by my local Sun's reckoning)
4105 Release 2005k - 2005-07-14 14:14:24 -0400
4107 The "leapseconds" file has been edited to reflect the recently
4108 announced leap second at the end of 2005.
4110 I've also deleted electronic mail addresses from the files as an
4114 Release 2005j - 2005-06-13 14:34:13 -0400
4116 These reflect changes to limit the length of time zone abbreviations
4117 and the characters used in those abbreviations.
4119 There are also changes to handle POSIX-style "quoted" timezone
4120 environment variables.
4122 The changes were circulated on the time zone mailing list; the only
4123 change since then was the removal of a couple of minimum-length of
4124 abbreviation checks.
4127 Release data2005i - 2005-04-21 15:04:16 -0400
4129 changes (most importantly to Nicaragua and Haiti) by Paul Eggert
4132 Release 2005h - 2005-04-04 11:24:47 -0400
4134 changes by Paul Eggert
4136 minor changes to Makefile and zdump.c to produce more useful output
4137 when doing a "make typecheck"
4140 Release 2005g - 2005-03-14 10:11:21 -0500
4142 changes by Paul Eggert (a change to current DST rules in Uruguay and
4143 an update to a link to time zone software)
4146 Release 2005f - 2005-03-01 08:45:32 -0500
4148 data and documentation changes by Paul Eggert
4151 Release 2005e - 2005-02-10 15:59:44 -0500
4156 Release code2005d - 2005-01-31 09:21:47 -0500
4158 make zic complain about links to links if the -v flag is used
4160 have "make public" do more code checking
4162 add an include to "localtime.c" for the benefit of gcc systems
4165 Release 2005c - 2005-01-17 18:36:29 -0500
4167 get better results when mktime runs on a system where time_t is double
4169 changes to the data files (most importantly to Paraguay)
4172 Release 2005b - 2005-01-10 09:19:54 -0500
4174 Get localtime and gmtime working on systems with exotic time_t types.
4176 Update the leap second commentary in the "leapseconds" file.
4179 Release 2005a - 2005-01-01 13:13:44 -0500
4184 Release code2004i - 2004-12-14 13:42:58 -0500
4186 Deal with systems where time_t is unsigned.
4189 Release code2004h - 2004-12-07 11:40:18 -0500
4191 64-bit-time_t changes
4194 Release 2004g - 2004-11-02 09:06:01 -0500
4196 update to Cuba (taking effect this weekend)
4198 other changes by Paul Eggert
4200 correction of the spelling of Oslo
4202 changed versions of difftime.c and private.h
4205 Release code2004f - 2004-10-21 10:25:22 -0400
4207 Cope with wide-ranging tm_year values.
4210 Release 2004e - 2004-10-11 14:47:21 -0400
4212 Brazil/Argentina/Israel changes by Paul Eggert
4214 changes to tz-link.htm by Paul
4216 one small fix to Makefile
4219 Release 2004d - 2004-09-22 08:27:29 -0400
4221 Avoid overflow problems when TM_YEAR_BASE is added to an integer.
4224 Release 2004c - 2004-08-11 12:06:26 -0400
4226 asctime-related changes
4228 (variants of) some of the documentation changes suggested by Paul Eggert
4231 Release 2004b - 2004-07-19 14:33:35 -0400
4233 data changes by Paul Eggert - most importantly, updates for Argentina
4236 Release 2004a - 2004-05-27 12:00:47 -0400
4238 changes by Paul Eggert
4240 Handle DST transitions that occur at the end of a month in some
4241 years but at the start of the following month in other years.
4243 Add a copy of the correspondence that's the basis for claims about
4244 DST in the Navajo Nation.
4247 Release 2003e - 2003-12-15 09:36:47 -0500
4249 changes by Arthur David Olson (primarily code changes)
4251 changes by Paul Eggert (primarily data changes)
4253 minor changes to "Makefile" and "northamerica" (in the latter case,
4254 optimization of the "Toronto" rules)
4257 Release 2003d - 2003-10-06 09:34:44 -0400
4259 changes by Paul Eggert
4262 Release 2003c - 2003-09-16 10:47:05 -0400
4264 Fix bad returns in zic.c's inleap function.
4265 Thanks to Bradley White for catching the problem!
4268 Release 2003b - 2003-09-16 07:13:44 -0400
4270 Add a "--version" option (and documentation) to the zic and zdump commands.
4272 changes to overflow/underflow checking in zic
4274 a localtime typo fix.
4276 Update the leapseconds and tz-art.htm files.
4279 Release 2003a - 2003-03-24 09:30:54 -0500
4281 changes by Paul Eggert
4283 a few additions and modifications to the tz-art.htm file
4286 Release 2002d - 2002-10-15 13:12:42 -0400
4288 changes by Paul Eggert, less the "Britain (UK)" change in iso3166.tab
4290 There's also a new time zone quote in "tz-art.htm".
4293 Release 2002c - 2002-04-04 11:55:20 -0500
4295 changes by Paul Eggert
4297 Change zic.c to avoid creating symlinks to files that don't exist.
4300 Release 2002b - 2002-01-28 12:56:03 -0500
4302 [These change notes are for Release 2002a, which was corrupted.
4303 2002b was a corrected version of 2002a.]
4305 changes by Paul Eggert
4307 Update the "leapseconds" file to note that there'll be no leap
4308 second at the end of June, 2002.
4310 Change "zic.c" to deal with a problem in handling the "Asia/Bishkek" zone.
4312 Change to "difftime.c" to avoid sizeof problems.
4315 Release 2001d - 2001-10-09 13:31:32 -0400
4317 changes by Paul Eggert
4320 Release 2001c - 2001-06-05 13:59:55 -0400
4322 changes by Paul Eggert and Andrew Brown
4325 Release 2001b - 2001-04-05 16:44:38 -0400
4327 changes by Paul Eggert (modulo jnorgard's typo fix)
4329 tz-art.htm has been HTMLified.
4332 Release 2001a - 2001-03-13 12:57:44 -0500
4334 changes by Paul Eggert
4336 An addition to the "leapseconds" file: comments with the text of the
4337 latest IERS leap second notice.
4339 Trailing white space has been removed from data file lines, and
4340 repeated spaces in "Rule Jordan" lines in the "asia" file have been
4344 Release 2000h - 2000-12-14 15:33:38 -0500
4346 changes by Paul Eggert
4348 one typo fix in the "art" file
4350 With providence, this is the last update of the millennium.
4353 Release 2000g - 2000-10-10 11:35:22 -0400
4355 changes by Paul Eggert
4357 correction of John Mackin's name submitted by Robert Elz
4359 Garry Shandling's Daylight Saving Time joke (!?!) from the recent
4360 Emmy Awards broadcast.
4363 Release 2000f - 2000-08-10 09:31:58 -0400
4365 changes by Paul Eggert
4367 Added information in "tz-art.htm" on a Seinfeld reference to DST.
4369 Error checking and messages in the "yearistype" script have been
4373 Release 2000e - 2000-07-31 09:27:54 -0400
4375 data changes by Paul Eggert
4377 a change to the default value of the defined constant HAVE_STRERROR
4379 the addition of a Dave Barry quote on DST to the tz-arts file
4382 Release 2000d - 2000-04-20 15:43:04 -0400
4384 changes to the documentation and code of strftime for C99 conformance
4386 a bug fix for date.c
4388 These are based on (though modified from) changes by Paul Eggert.
4391 Release 2000c - 2000-03-04 10:31:43 -0500
4393 changes by Paul Eggert
4396 Release 2000b - 2000-02-21 12:16:29 -0500
4398 changes by Paul Eggert and Joseph Myers
4400 modest tweaks to the tz-art.htm and tz-link.htm files
4403 Release 2000a - 2000-01-18 09:21:26 -0500
4405 changes by Paul Eggert
4407 The two hypertext documents have also been renamed.
4410 Release code1999i-data1999j - 1999-11-15 18:43:22 -0500
4412 Paul Eggert's changes
4414 additions to the "zic" manual page and the "Arts.htm" file
4417 Release code1999h-data1999i - 1999-11-08 14:55:21 -0500
4422 Release data1999h - 1999-10-07 03:50:29 -0400
4424 changes by Paul Eggert to "europe" (most importantly, fixing
4425 Lithuania and Estonia)
4428 Release 1999g - 1999-09-28 11:06:18 -0400
4430 data changes by Paul Eggert (most importantly, the change for
4431 Lebanon that buys correctness for this coming Sunday)
4433 The "code" file contains changes to "Makefile" and "checktab.awk" to
4434 allow better checking of time zone files before they are published.
4437 Release 1999f - 1999-09-23 09:48:14 -0400
4439 changes by Arthur David Olson and Paul Eggert
4442 Release 1999e - 1999-08-17 15:20:54 -0400
4444 changes circulated by Paul Eggert, although the change to handling
4445 of DST-specifying timezone names has been commented out for now
4446 (search for "XXX" in "localtime.c" for details). These files also
4447 do not make any changes to the start of DST in Brazil.
4449 In addition to Paul's changes, there are updates to "Arts.htm" and
4453 Release 1999d - 1999-03-30 11:31:07 -0500
4455 changes by Paul Eggert
4457 The Makefile's "make public" rule has also been changed to do a test
4458 compile of each individual time zone data file (which should help
4459 avoid problems such as the one we had with Nicosia).
4462 Release 1999c - 1999-03-25 09:47:47 -0500
4464 changes by Paul Eggert, most importantly the change for Chile.
4467 Release 1999b - 1999-02-01 17:51:44 -0500
4469 changes by Paul Eggert
4471 code changes (suggested by Mani Varadarajan, mani at be.com) for
4472 correct handling of symbolic links when building using a relative directory
4474 code changes to generate correct messages for failed links
4476 updates to the URLs in Arts.htm
4479 Release 1999a - 1999-01-19 16:20:29 -0500
4481 error message internationalizations and corrections in zic.c and
4482 zdump.c (as suggested by Vladimir Michl, vladimir.michl at upol.cz,
4486 Release code1998h-data1998i - 1998-10-01 09:56:10 -0400
4488 changes for Brazil, Chile, and Germany
4490 support for use of "24:00" in the input files for the time zone compiler
4493 Release code1998g-data1998h - 1998-09-24 10:50:28 -0400
4495 changes by Paul Eggert
4497 correction to a define in the "private.h" file
4500 Release data1998g - 1998-08-11 03:28:35 -0000
4501 [tzdata1998g.tar.gz is missing!]
4503 Lithuanian change provided by mgedmin at pub.osf.it
4505 Move creation of the GMT link with Etc/GMT to "etcetera" (from
4506 "backward") to ensure that the GMT file is created even where folks
4507 don't want the "backward" links (as suggested by Paul Eggert).
4510 Release data1998f - 1998-07-20 13:50:00 -0000
4511 [tzdata1998f.tar.gz is missing!]
4513 Update the "leapseconds" file to include the newly-announced
4514 insertion at the end of 1998.
4517 Release code1998f - 1998-06-01 10:18:31 -0400
4519 addition to localtime.c by Guy Harris
4522 Release 1998e - 1998-05-28 09:56:26 -0400
4524 The Makefile is changed to produce zoneinfo-posix rather than
4525 zoneinfo/posix, and to produce zoneinfo-leaps rather than
4528 data changes by Paul Eggert
4530 changes from Guy Harris to provide asctime_r and ctime_r
4532 A usno1998 file (substantially identical to usno1997) has been added.
4535 Release 1998d - 1998-05-14 11:58:34 -0400
4537 changes to comments (in particular, elimination of references to CIA maps).
4538 "Arts.htm", "WWW.htm", "asia", and "australasia" are the only places
4539 where changes occur.
4542 Release 1998c - 1998-02-28 12:32:26 -0500
4544 changes by Paul Eggert (save the "French correction," on which I'll
4545 wait for the dust to settle)
4549 changes and additions to Arts.htm
4552 Release 1998b - 1998-01-17 14:31:51 -0500
4554 URL cleanups and additions
4557 Release 1998a - 1998-01-13 12:37:35 -0500
4559 changes by Paul Eggert
4562 Release code1997i-data1997k - 1997-12-29 09:53:41 -0500
4564 changes by Paul Eggert, with minor modifications from Arthur David
4565 Olson to make the files more browser friendly
4568 Release code1997h-data1997j - 1997-12-18 17:47:35 -0500
4570 minor changes to put "TZif" at the start of each timezone information file
4572 a rule has also been added to the Makefile so you can
4574 to just recompile the zone information files (rather than doing a
4575 full "make install" with its other effects).
4578 Release data1997i - 1997-10-07 08:45:38 -0400
4580 changes to Africa by Paul Eggert
4583 Release code1997g-data1997h - 1997-09-04 16:56:54 -0400
4585 corrections for Uruguay (and other locations)
4587 Arthur David Olson's simple-minded fix allowing mktime to both
4588 correctly handle leap seconds and correctly handle tm_sec values
4589 upon which arithmetic has been performed.
4592 Release code1997f-data1997g - 1997-07-19 13:15:02 -0400
4594 Paul Eggert's updates
4596 a small change to a function prototype;
4598 "Music" has been renamed "Arts.htm", HTMLified, and augmented to
4599 include information on Around the World in Eighty Days.
4602 Release code1997e-data1997f - 1997-05-03 18:52:34 -0400
4604 fixes to zic's error handling
4606 changes inspired by the item circulated on Slovenia
4608 The description of Web resources has been HTMLified for browsing
4611 A new piece of tz-related music has been added to the "Music" file.
4614 Release code1997d-data1997e - 1997-03-29 12:48:52 -0500
4616 Paul Eggert's latest suggestions
4619 Release code1997c-data1997d - 1997-03-07 20:37:54 -0500
4621 changes to "zic.c" to correct performance of the "-s" option
4623 a new file "usno1997"
4626 Release data1997c - 1997-03-04 09:58:18 -0500
4631 Release 1997b - 1997-02-27 18:34:19 -0500
4633 The data file incorporates the 1997 leap second.
4635 The code file incorporates Arthur David Olson's take on the
4636 zic/multiprocessor/directory-creation situation.
4639 Release 1997a - 1997-01-21 09:11:10 -0500
4641 Paul Eggert's Antarctica (and other changes)
4643 Arthur David Olson finessed the "getopt" issue by checking against
4644 both -1 and EOF (regardless of POSIX, SunOS 4.1.1's manual says -1
4645 is returned while SunOS 5.5's manual says EOF is returned).
4648 Release code1996o-data1996n - 1996-12-27 21:42:05 -0500
4650 Paul Eggert's latest changes
4653 Release code1996n - 1996-12-16 09:42:02 -0500
4655 link snapping fix from Bruce Evans (via Garrett Wollman)
4658 Release data1996m - 1996-11-24 02:37:34 -0000
4659 [tzdata1996m.tar.gz is missing!]
4661 Paul Eggert's batch of changes
4664 Release code1996m-data1996l - 1996-11-05 14:00:12 -0500
4666 No functional changes here; the files have simply been changed to
4667 make more use of ISO style dates in comments. The names of the above
4668 files now include the year in full.
4671 Release code96l - 1996-09-08 17:12:20 -0400
4673 tzcode96k was missing a couple of pieces.
4676 Release 96k - 1996-09-08 16:06:22 -0400
4678 the latest round of changes from Paul Eggert
4680 the recent Year 2000 material
4683 Release code96j - 1996-07-30 13:18:53 -0400
4685 Set sp->typecnt as suggested by Timothy Patrick Murphy.
4688 Release code96i - 1996-07-27 20:11:35 -0400
4690 Paul's suggested patch for strftime %V week numbers
4693 Release data96i - 1996-07-01 18:13:04 -0400
4695 "northamerica" and "europe" changes by Paul Eggert
4698 Release code96h - 1996-06-05 08:02:21 -0400
4700 fix for handling transitions specified in Universal Time
4702 Some "public domain" notices have also been added.
4705 Release code96g - 1996-05-16 14:00:26 -0400
4707 fix for the simultaneous-DST-and-zone-change challenge
4710 Release data96h - 1996-05-09 17:40:51 -0400
4712 changes by Paul Eggert
4715 Release code96f-data96g - 1996-05-03 03:09:59 -0000
4716 [tzcode96f.tar.gz + tzdata96g.tar.gz are both missing!]
4718 The changes get us some of the way to fixing the problems noted in Paul
4719 Eggert's letter yesterday (in addition to a few others). The approach
4720 has been to make zic a bit smarter about figuring out what time zone
4721 abbreviations apply just after the time specified in the "UNTIL" part
4722 of a zone line. Putting the smarts in zic means avoiding having
4723 transition times show up in both "Zone" lines and "Rule" lines, which
4724 in turn avoids multiple transition time entries in time zone files.
4725 (This also makes the zic input files such as "europe" a bit shorter and
4726 should ease maintenance.)
4729 Release data96f - 1996-04-19 19:20:03 -0000
4730 [tzdata96f.tar.gz is missing!]
4732 The only changes are to the "northamerica" file; the time zone
4733 abbreviation for Denver is corrected to MST (and MDT), and the
4734 comments for Mexico have been updated.
4737 Release data96e - 1996-03-19 17:37:26 -0500
4739 Proposals by Paul Eggert, in particular the Portugal change that
4740 comes into play at the end of this month.
4743 Release data96d - 1996-03-18 20:49:39 -0500
4748 Release code96e - 1996-02-29 15:43:27 -0000
4749 [tzcode96e.tar.gz is missing!]
4751 internationalization changes and the fix to the documentation for strftime
4754 Release code96d-data96c - 1996-02-12 11:05:27 -0500
4756 The "code" file simply updates Bob Kridle's electronic address.
4758 The "data" file updates rules for Mexico.
4761 Release data96b - 1996-01-27 15:44:42 -0500
4766 Release code96c - 1996-01-16 16:58:15 -0500
4768 leap-year streamlining and binary-search changes
4773 Release code96b - 1996-01-10 20:42:39 -0500
4775 fixes and enhancements from Paul Eggert, including code that
4776 emulates the behavior of recent versions of the SunOS "date"
4780 Release 96a - 1996-01-06 09:08:24 -0500
4784 fixes to strftime.c for correct ISO 8601 week number generation,
4785 plus support for two new formats ('G' and 'g') to give ISO 8601 year
4786 numbers (which are not necessarily the same as calendar year numbers)
4789 Release code95i-data95m - 1995-12-21 12:46:47 -0500
4791 The latest revisions from Paul Eggert are included, the usno1995
4792 file has been updated, and a new file ("WWW") covering useful URLs
4796 Release code95h-data95l - 1995-12-19 18:10:12 -0500
4798 A simplification of a macro definition, a change to data for Sudan,
4799 and (for last minute shoppers) notes in the "Music" file on the CD
4803 Release code95g-data95k - 1995-10-30 10:32:47 -0500
4805 (slightly reformatted) 8-bit-clean proposed patch
4807 minor patch: US/Eastern -> America/New_York
4809 snapshot of the USNO's latest data ("usno1995")
4811 some other minor cleanups
4814 Release code95f-data95j - 1995-10-28 21:01:34 -0000
4815 [tzcode95f.tar.gz + tzdata95j.tar.gz are both missing!]
4819 support for 64-bit time_t's
4821 optimization in localtime.c
4824 Release code95e - 1995-10-13 13:23:57 -0400
4826 the mktime change to scan from future to past when trying to find time zone
4830 Release data95i - 1995-09-26 10:43:26 -0400
4832 For Canada/Central, guess that the Sun customer's "one week too
4833 early" was just a approximation, and the true error is one month
4834 too early. This is consistent with the rest of Canada.
4837 Release data95h - 1995-09-21 11:26:48 -0400
4839 latest changes from Paul Eggert
4842 Release code95d - 1995-09-14 11:14:45 -0400
4844 the addition of a "Music" file, which documents four recorded
4845 versions of the tune "Save That Time".
4848 Release data95g - 1995-09-01 17:21:36 -0400
4850 "yearistype" correction
4853 Release data95f - 1995-08-28 20:46:56 -0400
4855 Paul Eggert's change to the australasia file
4858 Release data95e - 1995-07-08 18:02:34 -0400
4860 The only change is a leap second at the end of this year.
4861 Thanks to Bradley White for forwarding news on the leap second.
4864 Release data95d - 1995-07-03 13:26:22 -0400
4866 Paul Eggert's changes
4869 Release data95c - 1995-07-02 19:19:28 -0400
4871 changes to "asia", "backward", "europe", and "southamerica"
4872 (read: northamericacentrics need not apply)
4875 Release code95c - 1995-03-13 14:00:46 -0500
4877 one-line fix for sign extension problems in detzcode
4880 Release 95b - 1995-03-04 11:22:38 -0500
4882 Minor changes in both:
4884 The "code" file contains a workaround for the lack of "unistd.h" in
4885 Microsoft C++ version 7.
4887 The "data" file contains a fixed "Link" for America/Shiprock.
4890 Release 94h - 1994-12-10 12:51:14 -0500
4894 * incorporate the changes to "zdump" and "date" to make changes to
4895 the "TZ" environment variable permanent;
4897 * incorporate the table changes by Paul Eggert;
4899 * include (and document) support for universal time specifications in
4900 data files - but do not (yet) include use of this feature in the
4903 Think of this as "TZ Classic" - the software has been set up not to break if
4904 universal time shows up in its input, and data entries have been
4905 left as is so as not to break existing implementations.
4908 Release data94f - 1994-08-20 12:56:09 -0400
4910 (with thanks!) the latest data updates from Paul Eggert
4913 Release data94e - 1994-06-04 13:13:53 -0400
4918 Release code94g - 1994-05-05 12:14:07 -0400
4920 fix missing "optind.c" and a reference to it in the Makefile
4923 Release code94f - 1994-05-05 13:00:33 -0000
4924 [tzcode94f.tar.gz is missing!]
4926 changes to avoid overflow in difftime, as well as changes to cope
4927 with the 52/53 challenge in strftime
4930 Release code94e - 1994-03-30 23:32:59 -0500
4932 change for the benefit of PCTS
4935 Release 94d - 1994-02-24 15:42:25 -0500
4937 Avoid clashes with POSIX semantics for zones such as GMT+4.
4939 Some other very minor housekeeping is also present.
4942 Release code94c - 1994-02-10 08:52:40 -0500
4944 Fix bug where mkdirs was broken unless you compile with
4945 -fwritable-strings (which is generally losing to do).
4948 Release 94b - 1994-02-07 10:04:33 -0500
4950 work by Paul Eggert who notes:
4952 I found another book of time zone histories by E W Whitman; it's not
4953 as extensive as Shanks but has a few goodies of its own. I used it
4954 to update the tables. I also fixed some more as a result of
4955 correspondence with Adam David and Peter Ilieve, and move some stray
4956 links from 'europe' to 'backward'. I corrected some scanning errors
4959 As far as the code goes, I fixed zic to allow years in the range
4960 INT_MIN to INT_MAX; this fixed a few boundary conditions around 1900.
4961 And I cleaned up the zic documentation a little bit.
4964 Release data94a - 1994-02-03 08:58:54 -0500
4966 It simply incorporates the recently announced leap second into the
4970 Release 93g - 1993-11-22 17:28:27 -0500
4972 Paul Eggert has provided a good deal of historic information (based
4973 on Shanks), and there are some code changes to deal with the buglets
4974 that crawled out in dealing with the new information.
4977 Release 93f - 1993-10-15 12:27:46 -0400
4979 Paul Eggert's changes
4982 Release 93e - 1993-09-05 21:21:44 -0400
4984 This has updated data for Israel, England, and Kwajalein. There's
4985 also an update to "zdump" to cope with Kwajalein's 24-hour jump.
4986 Thanks to Paul Eggert and Peter Ilieve for the changes.
4989 Release 93d - 1993-06-17 23:34:17 -0400
4991 new fix and new data on Israel
4994 Release 93c - 1993-06-06 19:31:55 -0400
4999 Release 93b - 1993-02-02 14:53:58 -0500
5001 updated "leapseconds" file
5004 Release 93 - 1993-01-08 07:01:06 -0500
5006 At kre's suggestion, the package has been split in two - a code piece
5007 (which also includes documentation) that's only of use to folks who
5008 want to recompile things and a data piece useful to anyone who can
5011 The new version has a few changes to the data files, a few
5012 portability changes, and an off-by-one fix (with thanks to
5013 Tom Karzes at deshaw.com for providing a description and a
5017 Release 92c - 1992-11-21 17:35:36 -0000
5018 [tz92c.tar.Z is missing!]
5020 The fallout from the latest round of DST transitions.
5022 There are changes for Portugal, Saskatchewan, and "Pacific-New";
5023 there's also a change to "zic.c" that makes it portable to more systems.
5026 Release 92 - 1992-04-25 18:17:03 -0000
5027 [tz92.tar.Z is missing!]
5029 By popular demand (well, at any rate, following a request by kre at munnari)
5032 The 1989 update of the time zone package featured:
5034 * POSIXization (including interpretation of POSIX-style TZ environment
5035 variables, provided by Guy Harris),
5036 * ANSIfication (including versions of "mktime" and "difftime"),
5037 * SVIDulation (an "altzone" variable)
5038 * MACHination (the "gtime" function)
5039 * corrections to some time zone data (including corrections to the rules
5040 for Great Britain and New Zealand)
5041 * reference data from the United States Naval Observatory for folks who
5042 want to do additional time zones
5043 * and the 1989 data for Saudi Arabia.
5045 (Since this code will be treated as "part of the implementation" in some
5046 places and as "part of the application" in others, there's no good way to
5047 name functions, such as timegm, that are not part of the proposed ANSI C
5048 standard; such functions have kept their old, underscore-free names in this
5051 And the "dysize" function has disappeared; it was present to allow
5052 compilation of the "date" command on old BSD systems, and a version of "date"
5053 is now provided in the package. The "date" command is not created when you
5054 "make all" since it may lack options provided by the version distributed with
5055 your operating system, or may not interact with the system in the same way
5056 the native version does.
5058 Since POSIX frowns on correct leap second handling, the default behavior of
5059 the "zic" command (in the absence of a "-L" option) has been changed to omit
5060 leap second information from its output files.
5066 This file contains copies of the part of each release announcement
5067 that talks about the changes in that release. The text has been
5068 adapted and reformatted for the purposes of this file.
5070 Traditionally a release R consists of a pair of tarball files,
5071 tzcodeR.tar.gz and tzdataR.tar.gz. However, some releases (e.g.,
5072 code2010a, data2012c) consist of just one or the other tarball, and a
5073 few (e.g., code2012c-data2012d) have tarballs with mixed version
5074 numbers. Recent releases also come in an experimental format
5075 consisting of a single tarball tzdb-R.tar.lz with extra data.
5077 Release timestamps are taken from the release's commit (for newer,
5078 Git-based releases), from the newest file in the tarball (for older
5079 releases, where this info is available) or from the email announcing
5080 the release (if all else fails; these are marked with a time zone
5081 abbreviation of -0000 and an "is missing!" comment).
5083 Earlier versions of the code and data were not announced on the tz
5084 list and are not summarized here.
5086 This file is in the public domain.