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NEWS revision 1.30
      1 News for the tz database
      2 
      3 Release 2020a - 2020-04-23 16:03:47 -0700
      4 
      5   Briefly:
      6     Morocco springs forward on 2020-05-31, not 2020-05-24.
      7     Canada's Yukon advanced to -07 year-round on 2020-03-08.
      8     America/Nuuk renamed from America/Godthab.
      9     zic now supports expiration dates for leap second lists.
     10 
     11   Changes to future timestamps
     12 
     13     Morocco's second spring-forward transition in 2020 will be May 31,
     14     not May 24 as predicted earlier.  (Thanks to Semlali Naoufal.)
     15     Adjust future-year predictions to use the first Sunday after the
     16     day after Ramadan, not the first Sunday after Ramadan.
     17 
     18     Canada's Yukon, represented by America/Whitehorse and
     19     America/Dawson, advanced to -07 year-round, beginning with its
     20     spring-forward transition on 2020-03-08, and will not fall back on
     21     2020-11-01.  Although a government press release calls this
     22     "permanent Pacific Daylight Saving Time", we prefer MST for
     23     consistency with nearby Dawson Creek, Creston, and Fort Nelson.
     24     (Thanks to Tim Parenti.)
     25 
     26   Changes to past timestamps
     27 
     28     Shanghai observed DST in 1919.  (Thanks to Phake Nick.)
     29 
     30   Changes to timezone identifiers
     31 
     32     To reflect current usage in English better, America/Godthab has
     33     been renamed to America/Nuuk.  A backwards-compatibility link
     34     remains for the old name.
     35 
     36   Changes to code
     37 
     38     localtime.c no longer mishandles timestamps after the last
     39     transition in a TZif file with leap seconds and with daylight
     40     saving time transitions projected into the indefinite future.
     41     For example, with TZ='America/Los_Angeles' with leap seconds,
     42     zdump formerly reported a DST transition on 2038-03-14
     43     from 01:59:32.999... to 02:59:33 instead of the correct transition
     44     from 01:59:59.999... to 03:00:00.
     45 
     46     zic -L now supports an Expires line in the leapseconds file, and
     47     truncates the TZif output accordingly.  This propagates leap
     48     second expiration information into the TZif file, and avoids the
     49     abovementioned localtime.c bug as well as similar bugs present in
     50     many client implementations.  If no Expires line is present, zic
     51     -L instead truncates the TZif output based on the #expires comment
     52     present in leapseconds files distributed by tzdb 2018f and later;
     53     however, this usage is obsolescent.  For now, the distributed
     54     leapseconds file has an Expires line that is commented out, so
     55     that the file can be fed to older versions of zic which ignore the
     56     commented-out line.  Future tzdb distributions are planned to
     57     contain a leapseconds file with an Expires line.
     58 
     59     The configuration macros HAVE_TZNAME and USG_COMPAT should now be
     60     set to 1 if the system library supports the feature, and 2 if not.
     61     As before, these macros are nonzero if tzcode should support the
     62     feature, zero otherwise.
     63 
     64     The configuration macro ALTZONE now has the same values with the
     65     same meaning as HAVE_TZNAME and USG_COMPAT.
     66 
     67     The code's defense against CRLF in leap-seconds.list is now
     68     portable to POSIX awk.  (Problem reported by Deborah Goldsmith.)
     69 
     70     Although the undocumented tzsetwall function is not changed in
     71     this release, it is now deprecated in preparation for removal in
     72     future releases.  Due to POSIX requirements, tzsetwall has not
     73     worked for some time.  Any code that uses it should instead use
     74     tzalloc(NULL) or, if portability trumps thread-safety, should
     75     unset the TZ environment variable.
     76 
     77   Changes to commentary
     78 
     79     The les-de-la-Madeleine and the Listuguj reserve are noted as
     80     following America/Halifax, and comments about Yukon's "south" and
     81     "north" have been corrected to say "east" and "west".  (Thanks to
     82     Jeffery Nichols.)
     83 
     84 
     85 Release 2019c - 2019-09-11 08:59:48 -0700
     86 
     87   Briefly:
     88     Fiji observes DST from 2019-11-10 to 2020-01-12.
     89     Norfolk Island starts observing Australian-style DST.
     90 
     91   Changes to future timestamps
     92 
     93     Fiji's next DST transitions will be 2019-11-10 and 2020-01-12
     94     instead of 2019-11-03 and 2020-01-19.  (Thanks to Raymond Kumar.)
     95     Adjust future guesses accordingly.
     96 
     97     Norfolk Island will observe Australian-style DST starting in
     98     spring 2019.  The first transition is on 2019-10-06.  (Thanks to
     99     Kyle Czech and Michael Deckers.)
    100 
    101   Changes to past timestamps
    102 
    103     Many corrections to time in Turkey from 1940 through 1985.
    104     (Thanks to Oya Vula via Alois Treindl, and to Kvan Yazan.)
    105 
    106     The Norfolk Island 1975-03-02 transition was at 02:00 standard
    107     time, not 02:00 DST.  (Thanks to Michael Deckers.)
    108 
    109     South Korea observed DST from 1948 through 1951.  Although this
    110     info was supposed to appear in release 2014j, a typo inadvertently
    111     suppressed the change.  (Thanks to Alois Treindl.)
    112 
    113     Detroit observed DST in 1967 and 1968 following the US DST rules,
    114     except that its 1967 DST began on June 14 at 00:01.  (Thanks to
    115     Alois Treindl for pointing out that the old data entries were
    116     probably wrong.)
    117 
    118     Fix several errors in pre-1970 transitions in Perry County, IN.
    119     (Thanks to Alois Triendl for pointing out the 1967/9 errors.)
    120 
    121     Edmonton did not observe DST in 1967 or 1969.  In 1946 Vancouver
    122     ended DST on 09-29 not 10-13, and Vienna ended DST on 10-07 not
    123     10-06.  In 1945 Knigsberg (now Kaliningrad) switched from +01/+02
    124     to +02/+03 on 04-10 not 01-01, and its +02/+03 is abbreviated
    125     EET/EEST, not CET/CEST.  (Thanks to Alois Triendl.)  In 1946
    126     Knigsberg switched to +03 on 04-07 not 01-01.
    127 
    128     In 1946 Louisville switched from CST to CDT on 04-28 at 00:01, not
    129     01-01 at 00:00.  (Thanks to Alois Treindl and Michael Deckers.)
    130     Also, it switched from CST to CDT on 1950-04-30, not 1947-04-27.
    131 
    132     The 1892-05-01 transition in Brussels was at 00:17:30, not at noon.
    133     (Thanks to Michael Deckers.)
    134 
    135   Changes to past time zone abbreviations and DST flags
    136 
    137     Hong Kong Winter Time, observed from 1941-10-01 to 1941-12-25,
    138     is now flagged as DST and is abbreviated HKWT not HKT.
    139 
    140   Changes to code
    141 
    142     leapseconds.awk now relies only on its input data, rather than
    143     also relying on its comments.  (Inspired by code from Dennis
    144     Ferguson and Chris Woodbury.)
    145 
    146     The code now defends against CRLFs in leap-seconds.list.
    147     (Thanks to Brian Inglis and Chris Woodbury.)
    148 
    149   Changes to documentation and commentary
    150 
    151     theory.html discusses leap seconds.  (Thanks to Steve Summit.)
    152 
    153     Nashville's newspapers dueled about the time of day in the 1950s.
    154     (Thanks to John Seigenthaler.)
    155 
    156     Liechtenstein observed Swiss DST in 1941/2.
    157     (Thanks to Alois Treindl.)
    158 
    159 
    160 Release 2019b - 2019-07-01 00:09:53 -0700
    161 
    162   Briefly:
    163     Brazil no longer observes DST.
    164     'zic -b slim' outputs smaller TZif files; please try it out.
    165     Palestine's 2019 spring-forward transition was on 03-29, not 03-30.
    166 
    167   Changes to future timestamps
    168 
    169     Brazil has canceled DST and will stay on standard time indefinitely.
    170     (Thanks to Steffen Thorsen, Marcus Diniz, and Daniel Soares de
    171     Oliveira.)
    172 
    173     Predictions for Morocco now go through 2087 instead of 2037, to
    174     work around a problem on newlib when using TZif files output by
    175     zic 2019a or earlier.  (Problem reported by David Gauchard.)
    176 
    177   Changes to past and future timestamps
    178 
    179     Palestine's 2019 spring transition was 03-29 at 00:00, not 03-30
    180     at 01:00.  (Thanks to Sharef Mustafa and Even Scharning.)  Guess
    181     future transitions to be March's last Friday at 00:00.
    182 
    183   Changes to past timestamps
    184 
    185     Hong Kong's 1941-06-15 spring-forward transition was at 03:00, not
    186     03:30.  Its 1945 transition from JST to HKT was on 11-18 at 02:00,
    187     not 09-15 at 00:00.  In 1946 its spring-forward transition was on
    188     04-21 at 00:00, not the previous day at 03:30.  From 1946 through
    189     1952 its fall-back transitions occurred at 04:30, not at 03:30.
    190     In 1947 its fall-back transition was on 11-30, not 12-30.
    191     (Thanks to P Chan.)
    192 
    193   Changes to past time zone abbreviations
    194 
    195     Italy's 1866 transition to Rome Mean Time was on December 12, not
    196     September 22.  This affects only the time zone abbreviation for
    197     Europe/Rome between those dates.  (Thanks to Stephen Trainor and
    198     Luigi Rosa.)
    199 
    200   Changes affecting metadata only
    201 
    202     Add info about the Crimea situation in zone1970.tab and zone.tab.
    203     (Problem reported by Serhii Demediuk.)
    204 
    205   Changes to code
    206 
    207     zic's new -b option supports a way to control data bloat and to
    208     test for year-2038 bugs in software that reads TZif files.
    209     'zic -b fat' and 'zic -b slim' generate larger and smaller output;
    210     for example, changing from fat to slim shrinks the Europe/London
    211     file from 3648 to 1599 bytes, saving about 56%.  Fat and slim
    212     files represent the same set of timestamps and use the same TZif
    213     format as documented in tzfile(5) and in Internet RFC 8536.
    214     Fat format attempts to work around bugs or incompatibilities in
    215     older software, notably software that mishandles 64-bit TZif data
    216     or uses obsolete TZ strings like "EET-2EEST" that lack DST rules.
    217     Slim format is more efficient and does not work around 64-bit bugs
    218     or obsolete TZ strings.  Currently zic defaults to fat format
    219     unless you compile with -DZIC_BLOAT_DEFAULT=\"slim\"; this
    220     out-of-the-box default is intended to change in future releases
    221     as the buggy software often mishandles timestamps anyway.
    222 
    223     zic no longer treats a set of rules ending in 2037 specially.
    224     Previously, zic assumed that such a ruleset meant that future
    225     timestamps could not be predicted, and therefore omitted a
    226     POSIX-like TZ string in the TZif output.  The old behavior is no
    227     longer needed for current tzdata, and caused problems with newlib
    228     when used with older tzdata (reported by David Gauchard).
    229 
    230     zic no longer generates some artifact transitions.  For example,
    231     Europe/London no longer has a no-op transition in January 1996.
    232 
    233   Changes to build procedure
    234 
    235     tzdata.zi now assumes zic 2017c or later.  This shrinks tzdata.zi
    236     by a percent or so.
    237 
    238   Changes to documentation and commentary
    239 
    240     The Makefile now documents the POSIXRULES macro as being obsolete,
    241     and similarly, zic's -p POSIXRULES option is now documented as
    242     being obsolete.  Although the POSIXRULES feature still exists and
    243     works as before, in practice it is rarely used for its intended
    244     purpose, and it does not work either in the default reference
    245     implementation (for timestamps after 2037) or in common
    246     implementations such as GNU/Linux (for contemporary timestamps).
    247     Since POSIXRULES was designed primarily as a temporary transition
    248     facility for System V platforms that died off decades ago, it is
    249     being decommissioned rather than institutionalized.
    250 
    251     New info on Bonin Islands and Marcus (thanks to Wakaba and Phake Nick).
    252 
    253 
    254 Release 2019a - 2019-03-25 22:01:33 -0700
    255 
    256   Briefly:
    257     Palestine "springs forward" on 2019-03-30 instead of 2019-03-23.
    258     Metlakatla "fell back" to rejoin Alaska Time on 2019-01-20 at 02:00.
    259 
    260   Changes to past and future timestamps
    261 
    262     Palestine will not start DST until 2019-03-30, instead of 2019-03-23 as
    263     previously predicted.  Adjust our prediction by guessing that spring
    264     transitions will be between 24 and 30 March, which matches recent practice
    265     since 2016.  (Thanks to Even Scharning and Tim Parenti.)
    266 
    267     Metlakatla ended its observance of Pacific standard time,
    268     rejoining Alaska Time, on 2019-01-20 at 02:00.  (Thanks to Ryan
    269     Stanley and Tim Parenti.)
    270 
    271   Changes to past timestamps
    272 
    273     Israel observed DST in 1980 (08-02/09-13) and 1984 (05-05/08-25).
    274     (Thanks to Alois Treindl and Isaac Starkman.)
    275 
    276   Changes to time zone abbreviations
    277 
    278     Etc/UCT is now a backward-compatibility link to Etc/UTC, instead
    279     of being a separate zone that generates the abbreviation "UCT",
    280     which nowadays is typically a typo.  (Problem reported by Isiah
    281     Meadows.)
    282 
    283   Changes to code
    284 
    285     zic now has an -r option to limit the time range of output data.
    286     For example, 'zic -r @1000000000' limits the output data to
    287     timestamps starting 1000000000 seconds after the Epoch.
    288     This helps shrink output size and can be useful for applications
    289     not needing the full timestamp history, such as TZDIST truncation;
    290     see Internet RFC 8536 section 5.1.  (Inspired by a feature request
    291     from Christopher Wong, helped along by bug reports from Wong and
    292     from Tim Parenti.)
    293 
    294   Changes to documentation
    295 
    296     Mention Internet RFC 8536 (February 2019), which documents TZif.
    297 
    298     tz-link.html now cites tzdata-meta
    299     <https://tzdata-meta.timtimeonline.com/>.
    300 
    301 
    302 Release 2018i - 2018-12-30 11:05:43 -0800
    303 
    304   Briefly:
    305     So Tom and Prncipe switches from +01 to +00 on 2019-01-01.
    306 
    307   Changes to future timestamps
    308 
    309     Due to a change in government, So Tom and Prncipe switches back
    310     from +01 to +00 on 2019-01-01 at 02:00.  (Thanks to Vadim
    311     Nasardinov and Michael Deckers.)
    312 
    313 
    314 Release 2018h - 2018-12-23 17:59:32 -0800
    315 
    316   Briefly:
    317     Qyzylorda, Kazakhstan moved from +06 to +05 on 2018-12-21.
    318     New zone Asia/Qostanay because Qostanay, Kazakhstan didn't move.
    319     Metlakatla, Alaska observes PST this winter only.
    320     Guess Morocco will continue to adjust clocks around Ramadan.
    321     Add predictions for Iran from 2038 through 2090.
    322 
    323   Changes to future timestamps
    324 
    325     Guess that Morocco will continue to fall back just before and
    326     spring forward just after Ramadan, the practice since 2012.
    327     (Thanks to Maamar Abdelkader.)  This means Morocco will observe
    328     negative DST during Ramadan in main and vanguard formats, and in
    329     rearguard format it stays in the +00 timezone and observes
    330     ordinary DST in all months other than Ramadan.  As before, extend
    331     this guesswork to the year 2037.  As a consequence, Morocco is
    332     scheduled to observe three DST transitions in some Gregorian years
    333     (e.g., 2033) due to the mismatch between the Gregorian and Islamic
    334     calendars.
    335 
    336     The table of exact transitions for Iranian DST has been extended.
    337     It formerly cut off before the year 2038 in a nod to 32-bit time_t.
    338     It now cuts off before 2091 as there is doubt about how the Persian
    339     calendar will treat 2091.  This change predicts DST transitions in
    340     2038-9, 2042-3, and 2046-7 to occur one day later than previously
    341     predicted.  As before, post-cutoff transitions are approximated.
    342 
    343   Changes to past and future timestamps
    344 
    345     Qyzylorda (aka Kyzylorda) oblast in Kazakhstan moved from +06 to
    346     +05 on 2018-12-21.  This is a zone split as Qostanay (aka
    347     Kostanay) did not switch, so create a zone Asia/Qostanay.
    348 
    349     Metlakatla moved from Alaska to Pacific standard time on 2018-11-04.
    350     It did not change clocks that day and remains on -08 this winter.
    351     (Thanks to Ryan Stanley.)  It will revert to the usual Alaska
    352     rules next spring, so this change affects only timestamps
    353     from 2018-11-04 through 2019-03-10.
    354 
    355   Change to past timestamps
    356 
    357     Kwajalein's 1993-08-20 transition from -12 to +12 was at 24:00,
    358     not 00:00.  I transcribed the time incorrectly from Shanks.
    359     (Thanks to Phake Nick.)
    360 
    361     Nauru's 1979 transition was on 02-10 at 02:00, not 05-01 at 00:00.
    362     (Thanks to Phake Nick.)
    363 
    364     Guam observed DST irregularly from 1959 through 1977.
    365     (Thanks to Phake Nick.)
    366 
    367     Hong Kong observed DST in 1941 starting 06-15 (not 04-01), then on
    368     10-01 changed standard time to +08:30 (not +08).  Its transition
    369     back to +08 after WWII was on 1945-09-15, not the previous day.
    370     Its 1904-10-30 change took effect at 01:00 +08 (not 00:00 LMT).
    371     (Thanks to Phake Nick, Steve Allen, and Joseph Myers.)  Also,
    372     its 1952 fallback was on 11-02 (not 10-25).
    373 
    374     This release contains many changes to timestamps before 1946 due
    375     to Japanese possession or occupation of Pacific/Chuuk,
    376     Pacific/Guam, Pacific/Kosrae, Pacific/Kwajalein, Pacific/Majuro,
    377     Pacific/Nauru, Pacific/Palau, and Pacific/Pohnpei.
    378     (Thanks to Phake Nick.)
    379 
    380     Assume that the Spanish East Indies was like the Philippines and
    381     observed American time until the end of 1844.  This affects
    382     Pacific/Chuuk, Pacific/Kosrae, Pacific/Palau, and Pacific/Pohnpei.
    383 
    384   Changes to past tm_isdst flags
    385 
    386     For the recent Morocco change, the tm_isdst flag should be 1 from
    387     2018-10-27 00:00 to 2018-10-28 03:00.  (Thanks to Michael Deckers.)
    388     Give a URL to the official decree.  (Thanks to Matt Johnson.)
    389 
    390 
    391 Release 2018g - 2018-10-26 22:22:45 -0700
    392 
    393   Briefly:
    394     Morocco switches to permanent +01 on 2018-10-28.
    395 
    396   Changes to future timestamps
    397 
    398     Morocco switches from +00/+01 to permanent +01 effective 2018-10-28,
    399     so its clocks will not fall back as previously scheduled.
    400     (Thanks to Mohamed Essedik Najd and Brian Inglis.)
    401 
    402   Changes to code
    403 
    404     When generating TZif files with leap seconds, zic no longer uses a
    405     format that trips up older 32-bit clients, fixing a bug introduced
    406     in 2018f.  (Reported by Daniel Fischer.)  Also, the zic workaround
    407     for QTBUG-53071 now also works for TZif files with leap seconds.
    408 
    409     The translator to rearguard format now rewrites the line
    410     "Rule Japan 1948 1951 - Sep Sat>=8 25:00 0 S" to
    411     "Rule Japan 1948 1951 - Sep Sun>=9  1:00 0 S".
    412     This caters to zic before 2007 and to Oracle TZUpdater 2.2.0
    413     and earlier.  (Reported by Christos Zoulas.)
    414 
    415   Changes to past time zone abbreviations
    416 
    417     Change HDT to HWT/HPT for WWII-era abbreviations in Hawaii.
    418     This reverts to 2011h, as the abbreviation change in 2011i was
    419     likely inadvertent.
    420 
    421   Changes to documentation
    422 
    423     tzfile.5 has new sections on interoperability issues.
    424 
    425 
    426 Release 2018f - 2018-10-18 00:14:18 -0700
    427 
    428   Briefly:
    429   Volgograd moves from +03 to +04 on 2018-10-28.
    430   Fiji ends DST 2019-01-13, not 2019-01-20.
    431   Most of Chile changes DST dates, effective 2019-04-06.
    432 
    433   Changes to future timestamps
    434 
    435     Volgograd moves from +03 to +04 on 2018-10-28 at 02:00.
    436     (Thanks to Alexander Fetisov and Stepan Golosunov.)
    437 
    438     Fiji ends DST 2019-01-13 instead of the 2019-01-20 previously
    439     predicted.  (Thanks to Raymond Kumar.)  Adjust future predictions
    440     accordingly.
    441 
    442     Most of Chile will end DST on the first Saturday in April at 24:00 mainland
    443     time, and resume DST on the first Saturday in September at 24:00 mainland
    444     time.  The changes are effective from 2019-04-06, and do not affect the
    445     Magallanes region modeled by America/Punta_Arenas.  (Thanks to Juan Correa
    446     and Tim Parenti.)  Adjust future predictions accordingly.
    447 
    448   Changes to past timestamps
    449 
    450     The 2018-05-05 North Korea 30-minute time zone change took place
    451     at 23:30 the previous day, not at 00:00 that day.
    452 
    453     China's 1988 spring-forward transition was on April 17, not
    454     April 10.  Its DST transitions in 1986/91 were at 02:00, not 00:00.
    455     (Thanks to P Chan.)
    456 
    457     Fix several issues for Macau before 1992.  Macau's pre-1904 LMT
    458     was off by 10 s.  Macau switched to +08 in 1904 not 1912, and
    459     temporarily switched to +09/+10 during World War II.  Macau
    460     observed DST in 1942/79, not 1961/80, and there were several
    461     errors for transition times and dates.  (Thanks to P Chan.)
    462 
    463     The 1948-1951 fallback transitions in Japan were at 25:00 on
    464     September's second Saturday, not at 24:00.  (Thanks to Phake Nick.)
    465     zic turns this into 01:00 on the day after September's second
    466     Saturday, which is the best that POSIX or C platforms can do.
    467 
    468     Incorporate 1940-1949 Asia/Shanghai DST transitions from a 2014
    469     paper by Li Yu, replacing more-questionable data from Shanks.
    470 
    471   Changes to time zone abbreviations
    472 
    473     Use "PST" and "PDT" for Philippine time.  (Thanks to Paul Goyette.)
    474 
    475   Changes to code
    476 
    477     zic now always generates TZif files where time type 0 is used for
    478     timestamps before the first transition.  This simplifies the
    479     reading of TZif files and should not affect behavior of existing
    480     TZif readers because the same set of time types is used; only
    481     their internal indexes may have changed.  This affects only the
    482     legacy zones EST5EDT, CST6CDT, MST7MDT, PST8PDT, CET, MET, and
    483     EET, which previously used nonzero types for these timestamps.
    484 
    485     Because of the type 0 change, zic no longer outputs a dummy
    486     transition at time -2**59 (before the Big Bang), as clients should
    487     no longer need this to handle historical timestamps correctly.
    488     This reverts a change introduced in 2013d and shrinks most TZif
    489     files by a few bytes.
    490 
    491     zic now supports negative time-of-day in Rule and Leap lines, e.g.,
    492     "Rule X min max - Apr lastSun -6:00 1:00 -" means the transition
    493     occurs at 18:00 on the Saturday before the last Sunday in April.
    494     This behavior was documented in 2018a but the code did not
    495     entirely match the documentation.
    496 
    497     localtime.c no longer requires at least one time type in TZif
    498     files that lack transitions or have a POSIX-style TZ string.  This
    499     future-proofs the code against possible future extensions to the
    500     format that would allow TZif files with POSIX-style TZ strings and
    501     without transitions or time types.
    502 
    503     A read-access subscript error in localtime.c has been fixed.
    504     It could occur only in TZif files with timecnt == 0, something that
    505     does not happen in practice now but could happen in future versions.
    506 
    507     localtime.c no longer ignores TZif POSIX-style TZ strings that
    508     specify only standard time.  Instead, these TZ strings now
    509     override the default time type for timestamps after the last
    510     transition (or for all timestamps if there are no transitions),
    511     just as DST strings specifying DST have always done.
    512 
    513     leapseconds.awk now outputs "#updated" and "#expires" comments,
    514     and supports leap seconds at the ends of months other than June
    515     and December.  (Inspired by suggestions from Chris Woodbury.)
    516 
    517   Changes to documentation
    518 
    519     New restrictions: A Rule name must start with a character that
    520     is neither an ASCII digit nor "-" nor "+", and an unquoted name
    521     should not use characters in the set "!$%&'()*,/:;<=>?@[\]^`{|}~".
    522     The latter restriction makes room for future extensions (a
    523     possibility noted by Tom Lane).
    524 
    525     tzfile.5 now documents what time types apply before the first and
    526     after the last transition, if any.
    527 
    528     Documentation now uses the spelling "timezone" for a TZ setting
    529     that determines timestamp history, and "time zone" for a
    530     geographic region currently sharing the same standard time.
    531 
    532     The name "TZif" is now used for the tz binary data format.
    533 
    534     tz-link.htm now mentions the A0 TimeZone Migration utilities.
    535     (Thanks to Aldrin Martoq for the link.)
    536 
    537   Changes to build procedure
    538 
    539     New 'make' target 'rearguard_tarballs' to build the rearguard
    540     tarball only.  This is a convenience on platforms that lack lzip
    541     if you want to build the rearguard tarball.  (Problem reported by
    542     Deborah Goldsmith.)
    543 
    544     tzdata.zi is now more stable from release to release.  (Problem
    545     noted by Tom Lane.)  It is also a bit shorter.
    546 
    547     tzdata.zi now can contain comment lines documenting configuration
    548     information, such as which data format was selected, which input
    549     files were used, and how leap seconds are treated.  (Problems
    550     noted by Lester Caine and Brian Inglis.)  If the Makefile defaults
    551     are used these comment lines are absent, for backward
    552     compatibility.  A redistributor intending to alter its copy of the
    553     files should also append "-LABEL" to the 'version' file's first
    554     line, where "LABEL" identifies the redistributor's change.
    555 
    556 
    557 Release 2018e - 2018-05-01 23:42:51 -0700
    558 
    559   Briefly:
    560 
    561     North Korea switches back to +09 on 2018-05-05.
    562     The main format uses negative DST again, for Ireland etc.
    563     'make tarballs' now also builds a rearguard tarball.
    564     New 's' and 'd' suffixes in SAVE columns of Rule and Zone lines.
    565 
    566   Changes to past and future timestamps
    567 
    568     North Korea switches back from +0830 to +09 on 2018-05-05.
    569     (Thanks to Kang Seonghoon, Arthur David Olson, Seo Sanghyeon,
    570     and Tim Parenti.)
    571 
    572     Bring back the negative-DST changes of 2018a, except be more
    573     compatible with data parsers that do not support negative DST.
    574     Also, this now affects historical timestamps in Namibia and the
    575     former Czechoslovakia, not just Ireland.  The main format now uses
    576     negative DST to model timestamps in Europe/Dublin (from 1971 on),
    577     Europe/Prague (1946/7), and Africa/Windhoek (1994/2017).  This
    578     does not affect UT offsets, only time zone abbreviations and the
    579     tm_isdst flag.  Also, this does not affect rearguard or vanguard
    580     formats; effectively the main format now uses vanguard instead of
    581     rearguard format.  Data parsers that do not support negative DST
    582     can still use data from the rearguard tarball described below.
    583 
    584   Changes to build procedure
    585 
    586     The command 'make tarballs' now also builds the tarball
    587     tzdataVERSION-rearguard.tar.gz, which is like tzdataVERSION.tar.gz
    588     except that it uses rearguard format intended for trailing-edge
    589     data parsers.
    590 
    591   Changes to data format and to code
    592 
    593     The SAVE column of Rule and Zone lines can now have an 's' or 'd'
    594     suffix, which specifies whether the adjusted time is standard time
    595     or daylight saving time.  If no suffix is given, daylight saving
    596     time is used if and only if the SAVE column is nonzero; this is
    597     the longstanding behavior.  Although this new feature is not used
    598     in tzdata, it could be used to specify the legal time in Namibia
    599     1994-2017, as opposed to the popular time (see below).
    600 
    601   Changes to past timestamps
    602 
    603     From 1994 through 2017 Namibia observed DST in winter, not summer.
    604     That is, it used negative DST, as Ireland still does.  This change
    605     does not affect UTC offsets; it affects only the tm_isdst flag and
    606     the abbreviation used during summer, which is now CAT, not WAST.
    607     Although (as noted by Michael Deckers) summer and winter time were
    608     both simply called "standard time" in Namibian law, in common
    609     practice winter time was considered to be DST (as noted by Stephen
    610     Colebourne).  The full effect of this change is only in vanguard
    611     and main format; in rearguard format, the tm_isdst flag is still
    612     zero in winter and nonzero in summer.
    613 
    614     In 1946/7 Czechoslovakia also observed negative DST in winter.
    615     The full effect of this change is only in vanguard and main
    616     formats; in rearguard format, it is modeled as plain GMT without
    617     daylight saving.  Also, the dates of some 1944/5 DST transitions
    618     in Czechoslovakia have been changed.
    619 
    620 
    621 Release 2018d - 2018-03-22 07:05:46 -0700
    622 
    623   Briefly:
    624 
    625   Palestine starts DST a week earlier in 2018.
    626   Add support for vanguard and rearguard data consumers.
    627   Add subsecond precision to source data format, though not to data.
    628 
    629   Changes to future timestamps
    630 
    631     In 2018, Palestine starts DST on March 24, not March 31.
    632     Adjust future predictions accordingly.  (Thanks to Sharef Mustafa.)
    633 
    634   Changes to past and future timestamps
    635 
    636     Casey Station in Antarctica changed from +11 to +08 on 2018-03-11
    637     at 04:00.  (Thanks to Steffen Thorsen.)
    638 
    639   Changes to past timestamps
    640 
    641     Historical transitions for Uruguay, represented by
    642     America/Montevideo, have been updated per official legal documents,
    643     replacing previous data mainly originating from the inventions of
    644     Shanks & Pottenger.  This has resulted in adjustments ranging from
    645     30 to 90 minutes in either direction over at least two dozen
    646     distinct periods ranging from one day to several years in length.
    647     A mere handful of pre-1991 transitions are unaffected; data since
    648     then has come from more reliable contemporaneous reporting.  These
    649     changes affect various timestamps in 1920-1923, 1936, 1939,
    650     1942-1943, 1959, 1966-1970, 1972, 1974-1980, and 1988-1990.
    651     Additionally, Uruguay's pre-standard-time UT offset has been
    652     adjusted westward by 7 seconds, from UT-03:44:44 to UT-03:44:51, to
    653     match the location of the Observatory of the National Meteorological
    654     Institute in Montevideo.
    655     (Thanks to Jeremie Bonjour, Tim Parenti, and Michael Deckers.)
    656 
    657     Enderbury and Kiritimati skipped New Year's Eve 1994, not
    658     New Year's Day 1995.  (Thanks to Kerry Shetline.)
    659 
    660     Fix the 1912-01-01 transition for Portugal and its colonies.
    661     This transition was at 00:00 according to the new UT offset, not
    662     according to the old one.  Also assume that Cape Verde switched on
    663     the same date as the rest, not in 1907.  This affects
    664     Africa/Bissau, Africa/Sao_Tome, Asia/Macau, Atlantic/Azores,
    665     Atlantic/Cape_Verde, Atlantic/Madeira, and Europe/Lisbon.
    666     (Thanks to Michael Deckers.)
    667 
    668     Fix an off-by-1 error for pre-1913 timestamps in Jamaica and in
    669     Turks & Caicos.
    670 
    671   Changes to past time zone abbreviations
    672 
    673     MMT took effect in Uruguay from 1908-06-10, not 1898-06-28.  There
    674     is no clock change associated with the transition.
    675 
    676   Changes to build procedure
    677 
    678     The new DATAFORM macro in the Makefile lets the installer choose
    679     among three source data formats.  The idea is to lessen downstream
    680     disruption when data formats are improved.
    681 
    682     * DATAFORM=vanguard installs from the latest, bleeding-edge
    683       format.  DATAFORM=main (the default) installs from the format
    684       used in the 'africa' etc. files.  DATAFORM=rearguard installs
    685       from a trailing-edge format.  Eventually, elements of today's
    686       vanguard format should move to the main format, and similarly
    687       the main format's features should eventually move to the
    688       rearguard format.
    689 
    690     * In the current version, the main and rearguard formats are
    691       identical and match that of 2018c, so this change does not
    692       affect default behavior.  The vanguard format currently contains
    693       one feature not in the main format: negative SAVE values.  This
    694       improves support for Ireland, which uses Irish Standard Time
    695       (IST, UTC+01) in summer and GMT (UTC) in winter.  tzcode has
    696       supported negative SAVE values for decades, and this feature
    697       should move to the main format soon.  However, it will not move
    698       to the rearguard format for quite some time because some
    699       downstream parsers do not support it.
    700 
    701     * The build procedure constructs three files vanguard.zi, main.zi,
    702       and rearguard.zi, one for each format.  Although the files
    703       represent essentially the same data, they may have minor
    704       discrepancies that users are not likely to notice.  The files
    705       are intended for downstream data consumers and are not
    706       installed.  Zoneinfo parsers that do not support negative SAVE values
    707       should start using rearguard.zi, so that they will be unaffected
    708       when the negative-DST feature moves from vanguard to main.
    709       Bleeding-edge Zoneinfo parsers that support the new features
    710       already can use vanguard.zi; in this respect, current tzcode is
    711       bleeding-edge.
    712 
    713     The Makefile should now be safe for parallelized builds, and 'make
    714     -j to2050new.tzs' is now much faster on a multiprocessor host
    715     with GNU Make.
    716 
    717     When built with -DSUPPRESS_TZDIR, the tzcode library no longer
    718     prepends TZDIR/ to file names that do not begin with '/'.  This is
    719     not recommended for general use, due to its security implications.
    720     (From a suggestion by Manuela Friedrich.)
    721 
    722   Changes to code
    723 
    724     zic now accepts subsecond precision in expressions like
    725     00:19:32.13, which is approximately the legal time of the
    726     Netherlands from 1835 to 1937.  However, because it is
    727     questionable whether the few recorded uses of non-integer offsets
    728     had subsecond precision in practice, there are no plans for tzdata
    729     to use this feature.  (Thanks to Steve Allen for pointing out
    730     the limitations of historical data in this area.)
    731 
    732     The code is a bit more portable to MS-Windows.  Installers can
    733     compile with -DRESERVE_STD_EXT_IDS on MS-Windows platforms that
    734     reserve identifiers like 'localtime'.  (Thanks to Manuela
    735     Friedrich.)
    736 
    737   Changes to documentation and commentary
    738 
    739     theory.html now outlines tzdb's extensions to POSIX's model for
    740     civil time, and has a section "POSIX features no longer needed"
    741     that lists POSIX API components that are now vestigial.
    742     (From suggestions by Steve Summit.)  It also better distinguishes
    743     time zones from tz regions.  (From a suggestion by Guy Harris.)
    744 
    745     Commentary is now more consistent about using the phrase "daylight
    746     saving time", to match the C name tm_isdst.  Daylight saving time
    747     need not occur in summer, and need not have a positive offset from
    748     standard time.
    749 
    750     Commentary about historical transitions in Uruguay has been expanded
    751     with links to many relevant legal documents.
    752     (Thanks to Tim Parenti.)
    753 
    754     Commentary now uses some non-ASCII characters with Unicode value
    755     less than U+0100, as they can be useful and should work even with
    756     older editors such as XEmacs.
    757 
    758 
    759 Release 2018c - 2018-01-22 23:00:44 -0800
    760 
    761   Briefly:
    762   Revert Irish changes that relied on negative SAVE values.
    763 
    764   Changes to tm_isdst
    765 
    766     Revert the 2018a change to Europe/Dublin.  As before, this change
    767     does not affect UT offsets or abbreviations; it affects only
    768     whether timestamps are considered to be standard time or
    769     daylight-saving time, as expressed in the tm_isdst flag of C's
    770     struct tm type.  This reversion is intended to be a temporary
    771     workaround for problems discovered with downstream uses of
    772     releases 2018a and 2018b, which implemented Irish time by using
    773     negative SAVE values in the Eire rules of the 'europe' file.
    774     Although negative SAVE values have been part of tzcode for many
    775     years and are supported by many platforms, they were not
    776     documented before 2018a and ICU and OpenJDK do not currently
    777     support them.  A mechanism to export data to platforms lacking
    778     support for negative DST is planned to be developed before the
    779     change is reapplied.  (Problems reported by Deborah Goldsmith and
    780     Stephen Colebourne.)
    781 
    782   Changes to past timestamps
    783 
    784     Japanese DST transitions (1948-1951) were Sundays at 00:00, not
    785     Saturdays or Sundays at 02:00.  (Thanks to Takayuki Nikai.)
    786 
    787   Changes to build procedure
    788 
    789     The build procedure now works around mawk 1.3.3's lack of support
    790     for character class expressions.  (Problem reported by Ohyama.)
    791 
    792 
    793 Release 2018b - 2018-01-17 23:24:48 -0800
    794 
    795   Briefly:
    796   Fix a packaging problem in tz2018a, which was missing 'pacificnew'.
    797 
    798   Changes to build procedure
    799 
    800     The distribution now contains the file 'pacificnew' again.
    801     This file was inadvertantly omitted in the 2018a distribution.
    802     (Problem reported by Matias Fonzo.)
    803 
    804 
    805 Release 2018a - 2018-01-12 22:29:21 -0800
    806 
    807   Briefly:
    808   So Tom and Prncipe switched from +00 to +01.
    809   Brazil's DST will now start on November's first Sunday.
    810   Ireland's standard time is now in the summer, not the winter.
    811   Use Debian-style installation locations, instead of 4.3BSD-style.
    812   New zic option -t.
    813 
    814   Changes to past and future timestamps
    815 
    816     So Tom and Prncipe switched from +00 to +01 on 2018-01-01 at
    817     01:00.  (Thanks to Steffen Thorsen and Michael Deckers.)
    818 
    819   Changes to future timestamps
    820 
    821     Starting in 2018 southern Brazil will begin DST on November's
    822     first Sunday instead of October's third Sunday.  (Thanks to
    823     Steffen Thorsen.)
    824 
    825   Changes to past timestamps
    826 
    827     A discrepancy of 4 s in timestamps before 1931 in South Sudan has
    828     been corrected.  The 'backzone' and 'zone.tab' files did not agree
    829     with the 'africa' and 'zone1970.tab' files.  (Problem reported by
    830     Michael Deckers.)
    831 
    832     The abbreviation invented for Bolivia Summer Time (1931-2) is now
    833     BST instead of BOST, to be more consistent with the convention
    834     used for Latvian Summer Time (1918-9) and for British Summer Time.
    835 
    836   Changes to tm_isdst
    837 
    838     Change Europe/Dublin so that it observes Irish Standard Time (UT
    839     +01) in summer and GMT (as negative daylight-saving) in winter,
    840     instead of observing standard time (GMT) in winter and Irish
    841     Summer Time (UT +01) in summer.  This change does not affect UT
    842     offsets or abbreviations; it affects only whether timestamps are
    843     considered to be standard time or daylight-saving time, as
    844     expressed in the tm_isdst flag of C's struct tm type.
    845     (Discrepancy noted by Derick Rethans.)
    846 
    847   Changes to build procedure
    848 
    849     The default installation locations have been changed to mostly
    850     match Debian circa 2017, instead of being designed as an add-on to
    851     4.3BSD circa 1986.  This affects the Makefile macros TOPDIR,
    852     TZDIR, MANDIR, and LIBDIR.  New Makefile macros TZDEFAULT, USRDIR,
    853     USRSHAREDIR, BINDIR, ZDUMPDIR, and ZICDIR let installers tailor
    854     locations more precisely.  (This responds to suggestions from
    855     Brian Inglis and from Steve Summit.)
    856 
    857     The default installation procedure no longer creates the
    858     backward-compatibility link US/Pacific-New, which causes
    859     confusion during user setup (e.g., see Debian bug 815200).
    860     Use 'make BACKWARD="backward pacificnew"' to create the link
    861     anyway, for now.  Eventually we plan to remove the link entirely.
    862 
    863     tzdata.zi now contains a version-number comment.
    864     (Suggested by Tom Lane.)
    865 
    866     The Makefile now quotes values like BACKWARD more carefully when
    867     passing them to the shell.  (Problem reported by Zefram.)
    868 
    869     Builders no longer need to specify -DHAVE_SNPRINTF on platforms
    870     that have snprintf and use pre-C99 compilers.  (Problem reported
    871     by Jon Skeet.)
    872 
    873   Changes to code
    874 
    875     zic has a new option -t FILE that specifies the location of the
    876     file that determines local time when TZ is unset.  The default for
    877     this location can be configured via the new TZDEFAULT makefile
    878     macro, which defaults to /etc/localtime.
    879 
    880     Diagnostics and commentary now distinguish UT from UTC more
    881     carefully; see theory.html for more information about UT vs UTC.
    882 
    883     zic has been ported to GCC 8's -Wstringop-truncation option.
    884     (Problem reported by Martin Sebor.)
    885 
    886   Changes to documentation and commentary
    887 
    888     The zic man page now documents the longstanding behavior that
    889     times and years can be out of the usual range, with negative times
    890     counting backwards from midnight and with year 0 preceding year 1.
    891     (Problem reported by Michael Deckers.)
    892 
    893     The theory.html file now mentions the POSIX limit of six chars
    894     per abbreviation, and lists alphabetic abbreviations used.
    895 
    896     The files tz-art.htm and tz-link.htm have been renamed to
    897     tz-art.html and tz-link.html, respectively, for consistency with
    898     other file names and to simplify web server configuration.
    899 
    900 
    901 Release 2017c - 2017-10-20 14:49:34 -0700
    902 
    903   Briefly:
    904   Northern Cyprus switches from +03 to +02/+03 on 2017-10-29.
    905   Fiji ends DST 2018-01-14, not 2018-01-21.
    906   Namibia switches from +01/+02 to +02 on 2018-04-01.
    907   Sudan switches from +03 to +02 on 2017-11-01.
    908   Tonga likely switches from +13/+14 to +13 on 2017-11-05.
    909   Turks & Caicos switches from -04 to -05/-04 on 2018-11-04.
    910   A new file tzdata.zi now holds a small text copy of all data.
    911   The zic input format has been regularized slightly.
    912 
    913   Changes to future timestamps
    914 
    915     Northern Cyprus has decided to resume EU rules starting
    916     2017-10-29, thus reinstituting winter time.
    917 
    918     Fiji ends DST 2018-01-14 instead of the 2018-01-21 previously
    919     predicted.  (Thanks to Dominic Fok.)  Adjust future predictions
    920     accordingly.
    921 
    922     Namibia will switch from +01 with DST to +02 all year on
    923     2017-09-03 at 02:00.  This affects UT offsets starting 2018-04-01
    924     at 02:00.  (Thanks to Steffen Thorsen.)
    925 
    926     Sudan will switch from +03 to +02 on 2017-11-01.  (Thanks to Ahmed
    927     Atyya and Yahia Abdalla.)  South Sudan is not switching, so
    928     Africa/Juba is no longer a link to Africa/Khartoum.
    929 
    930     Tonga has likely ended its experiment with DST, and will not
    931     adjust its clocks on 2017-11-05.  Although Tonga has not announced
    932     whether it will continue to observe DST, the IATA is assuming that
    933     it will not.  (Thanks to David Wade.)
    934 
    935     Turks & Caicos will switch from -04 all year to -05 with US DST on
    936     2018-03-11 at 03:00.  This affects UT offsets starting 2018-11-04
    937     at 02:00.  (Thanks to Steffen Thorsen.)
    938 
    939   Changes to past timestamps
    940 
    941     Namibia switched from +02 to +01 on 1994-03-21, not 1994-04-03.
    942     (Thanks to Arthur David Olson.)
    943 
    944     Detroit did not observe DST in 1967.
    945 
    946     Use railway time for Asia/Kolkata before 1941, by switching to
    947     Madras local time (UT +052110) in 1870, then to IST (UT +0530) in
    948     1906.  Also, treat 1941-2's +0630 as DST, like 1942-5.
    949 
    950     Europe/Dublin's 1946 and 1947 fallback transitions occurred at
    951     02:00 standard time, not 02:00 DST.  (Thanks to Michael Deckers.)
    952 
    953     Pacific/Apia and Pacific/Pago_Pago switched from Antipodean to
    954     American time in 1892, not 1879.  (Thanks to Michael Deckers.)
    955 
    956     Adjust the 1867 transition in Alaska to better reflect the
    957     historical record, by changing it to occur on 1867-10-18 at 15:30
    958     Sitka time rather than at the start of 1867-10-17 local time.
    959     Although strictly speaking this is accurate only for Sitka,
    960     the rest of Alaska's blanks need to be filled in somehow.
    961 
    962     Fix off-by-one errors in UT offsets for Adak and Nome before 1867.
    963     (Thanks to Michael Deckers.)
    964 
    965     Add 7 s to the UT offset in Asia/Yangon before 1920.
    966 
    967   Changes to zone names
    968 
    969     Remove Canada/East-Saskatchewan from the 'backward' file, as it
    970     exceeded the 14-character limit and was an unused misnomer anyway.
    971 
    972   Changes to build procedure
    973 
    974     To support applications that prefer to read time zone data in text
    975     form, two zic input files tzdata.zi and leapseconds are now
    976     installed by default.  The commands 'zic tzdata.zi' and 'zic -L
    977     leapseconds tzdata.zi' can reproduce the tzdata binary files
    978     without and with leap seconds, respectively.  To prevent these two
    979     new files from being installed, use 'make TZDATA_TEXT=', and to
    980     suppress leap seconds from the tzdata text installation, use 'make
    981     TZDATA_TEXT=tzdata.zi'.
    982 
    983     'make BACKWARD=' now suppresses backward-compatibility names
    984     like 'US/Pacific' that are defined in the 'backward' and
    985     'pacificnew' files.
    986 
    987     'make check' now works on systems that lack a UTF-8 locale,
    988     or that lack the nsgmls program.  Set UTF8_LOCALE to configure
    989     the name of a UTF-8 locale, if you have one.
    990 
    991     Y2K runtime checks are no longer enabled by default.  Add
    992     -DDEPRECATE_TWO_DIGIT_YEARS to CFLAGS to enable them, instead of
    993     adding -DNO_RUN_TIME_WARNINGS_ABOUT_YEAR_2000_PROBLEMS_THANK_YOU
    994     to disable them.  (New name suggested by Brian Inglis.)
    995 
    996     The build procedure for zdump now works on AIX 7.1.
    997     (Problem reported by Kees Dekker.)
    998 
    999   Changes to code
   1000 
   1001     zic and the reference runtime now reject multiple leap seconds
   1002     within 28 days of each other, or leap seconds before the Epoch.
   1003     As a result, support for double leap seconds, which was
   1004     obsolescent and undocumented, has been removed.  Double leap
   1005     seconds were an error in the C89 standard; they have never existed
   1006     in civil timekeeping.  (Thanks to Robert Elz and Bradley White for
   1007     noticing glitches in the code that uncovered this problem.)
   1008 
   1009     zic now warns about use of the obsolescent and undocumented -y
   1010     option, and about use of the obsolescent TYPE field of Rule lines.
   1011 
   1012     zic now allows unambiguous abbreviations like "Sa" and "Su" for
   1013     weekdays; formerly it rejected them due to a bug.  Conversely, zic
   1014     no longer considers non-prefixes to be abbreviations; for example,
   1015     it no longer accepts "lF" as an abbreviation for "lastFriday".
   1016     Also, zic warns about the undocumented usage with a "last-"
   1017     prefix, e.g., "last-Fri".
   1018 
   1019     Similarly, zic now accepts the unambiguous abbreviation "L" for
   1020     "Link" in ordinary context and for "Leap" in leap-second context.
   1021     Conversely, zic no longer accepts non-prefixes such as "La" as
   1022     abbreviations for words like "Leap".
   1023 
   1024     zic no longer accepts leap second lines in ordinary input, or
   1025     ordinary lines in leap second input.  Formerly, zic sometimes
   1026     warned about this undocumented usage and handled it incorrectly.
   1027 
   1028     The new macro HAVE_TZNAME governs whether the tzname external
   1029     variable is exported, instead of USG_COMPAT.  USG_COMPAT now
   1030     governs only the external variables "timezone" and "daylight".
   1031     This change is needed because the three variables are not in the
   1032     same category: although POSIX requires tzname, it specifies the
   1033     other two variables as optional.  Also, USG_COMPAT is now 1 or 0:
   1034     if not defined, the code attempts to guess it from other macros.
   1035 
   1036     localtime.c and difftime.c no longer require stdio.h, and .c files
   1037     other than zic.c no longer require sys/wait.h.
   1038 
   1039     zdump.c no longer assumes snprintf.  (Reported by Jonathan Leffler.)
   1040 
   1041     Calculation of time_t extrema works around a bug in GCC 4.8.4
   1042     (Reported by Stan Shebs and Joseph Myers.)
   1043 
   1044     zic.c no longer mistranslates formats of line numbers in non-English
   1045     locales.  (Problem reported by Benno Schulenberg.)
   1046 
   1047     Several minor changes have been made to the code to make it a
   1048     bit easier to port to MS-Windows and Solaris.  (Thanks to Kees
   1049     Dekker for reporting the problems.)
   1050 
   1051   Changes to documentation and commentary
   1052 
   1053     The two new files 'theory.html' and 'calendars' contain the
   1054     contents of the removed file 'Theory'.  The goal is to document
   1055     tzdb theory more accessibly.
   1056 
   1057     The zic man page now documents abbreviation rules.
   1058 
   1059     tz-link.htm now covers how to apply tzdata changes to clients.
   1060     (Thanks to Jorge Fbregas for the AIX link.)  It also mentions MySQL.
   1061 
   1062     The leap-seconds.list URL has been updated to something that is
   1063     more reliable for tzdb.  (Thanks to Tim Parenti and Brian Inglis.)
   1064 
   1065 Release 2017b - 2017-03-17 07:30:38 -0700
   1066 
   1067   Briefly: Haiti has resumed DST.
   1068 
   1069   Changes to past and future timestamps
   1070 
   1071     Haiti resumed observance of DST in 2017.  (Thanks to Steffen Thorsen.)
   1072 
   1073   Changes to past timestamps
   1074 
   1075     Liberia changed from -004430 to +00 on 1972-01-07, not 1972-05-01.
   1076 
   1077     Use "MMT" to abbreviate Liberia's time zone before 1972, as "-004430"
   1078     is one byte over the POSIX limit.  (Problem reported by Derick Rethans.)
   1079 
   1080   Changes to code
   1081 
   1082     The reference localtime implementation now falls back on the
   1083     current US daylight-saving transition rules rather than the
   1084     1987-2006 rules.  This fallback occurs only when (1) the TZ
   1085     environment variable has a value like "AST4ADT" that asks
   1086     for daylight saving time but does not specify the rules, (2) there
   1087     is no file by that name, and (3) the TZDEFRULES file cannot be
   1088     loaded.  (Thanks to Tom Lane.)
   1089 
   1090 
   1091 Release 2017a - 2017-02-28 00:05:36 -0800
   1092 
   1093   Briefly: Southern Chile moves from -04/-03 to -03, and Mongolia
   1094   discontinues DST.
   1095 
   1096   Changes to future timestamps
   1097 
   1098     Mongolia no longer observes DST.  (Thanks to Ganbold Tsagaankhuu.)
   1099 
   1100     Chile's Region of Magallanes moves from -04/-03 to -03 year-round.
   1101     Its clocks diverge from America/Santiago starting 2017-05-13 at
   1102     23:00, hiving off a new zone America/Punta_Arenas.  Although the
   1103     Chilean government says this change expires in May 2019, for now
   1104     assume it's permanent.  (Thanks to Juan Correa and Deborah
   1105     Goldsmith.)  This also affects Antarctica/Palmer.
   1106 
   1107   Changes to past timestamps
   1108 
   1109     Fix many entries for historical timestamps for Europe/Madrid
   1110     before 1979, to agree with tables compiled by Pere Planesas of the
   1111     National Astronomical Observatory of Spain.  As a side effect,
   1112     this changes some timestamps for Africa/Ceuta before 1929, which
   1113     are probably guesswork anyway.  (Thanks to Steve Allen and
   1114     Pierpaolo Bernardi for the heads-ups, and to Michael Deckers for
   1115     correcting the 1901 transition.)
   1116 
   1117     Ecuador observed DST from 1992-11-28 to 1993-02-05.
   1118     (Thanks to Alois Treindl.)
   1119 
   1120     Asia/Atyrau and Asia/Oral were at +03 (not +04) before 1930-06-21.
   1121     (Thanks to Stepan Golosunov.)
   1122 
   1123   Changes to past and future time zone abbreviations
   1124 
   1125     Switch to numeric time zone abbreviations for South America, as
   1126     part of the ongoing project of removing invented abbreviations.
   1127     This avoids the need to invent an abbreviation for the new Chilean
   1128     new zone.  Similarly, switch from invented to numeric time zone
   1129     abbreviations for Afghanistan, American Samoa, the Azores,
   1130     Bangladesh, Bhutan, the British Indian Ocean Territory, Brunei,
   1131     Cape Verde, Chatham Is, Christmas I, Cocos (Keeling) Is, Cook Is,
   1132     Dubai, East Timor, Eucla, Fiji, French Polynesia, Greenland,
   1133     Indochina, Iran, Iraq, Kiribati, Lord Howe, Macquarie, Malaysia,
   1134     the Maldives, Marshall Is, Mauritius, Micronesia, Mongolia,
   1135     Myanmar, Nauru, Nepal, New Caledonia, Niue, Norfolk I, Palau,
   1136     Papua New Guinea, the Philippines, Pitcairn, Qatar, Runion, St
   1137     Pierre & Miquelon, Samoa, Saudi Arabia, Seychelles, Singapore,
   1138     Solomon Is, Tokelau, Tuvalu, Wake, Vanuatu, Wallis & Futuna, and
   1139     Xinjiang; for 20-minute daylight saving time in Ghana before 1943;
   1140     for half-hour daylight saving time in Belize before 1944 and in
   1141     the Dominican Republic before 1975; and for Canary Islands before
   1142     1946, for Guinea-Bissau before 1975, for Iceland before 1969, for
   1143     Indian Summer Time before 1942, for Indonesia before around 1964,
   1144     for Kenya before 1960, for Liberia before 1973, for Madeira before
   1145     1967, for Namibia before 1943, for the Netherlands in 1937-9, for
   1146     Pakistan before 1971, for Western Sahara before 1977, and for
   1147     Zaporozhye in 1880-1924.
   1148 
   1149     For Alaska time from 1900 through 1967, instead of "CAT" use the
   1150     abbreviation "AST", the abbreviation commonly used at the time
   1151     (Atlantic Standard Time had not been standardized yet).  Use "AWT"
   1152     and "APT" instead of the invented abbreviations "CAWT" and "CAPT".
   1153 
   1154     Use "CST" and "CDT" instead of invented abbreviations for Macau
   1155     before 1999 and Taiwan before 1938, and use "JST" instead of the
   1156     invented abbreviation "JCST" for Japan and Korea before 1938.
   1157 
   1158   Change to database entry category
   1159 
   1160     Move the Pacific/Johnston link from 'australasia' to 'backward',
   1161     since Johnston is now uninhabited.
   1162 
   1163   Changes to code
   1164 
   1165     zic no longer mishandles some transitions in January 2038 when it
   1166     attempts to work around Qt bug 53071.  This fixes a bug affecting
   1167     Pacific/Tongatapu that was introduced in zic 2016e.  localtime.c
   1168     now contains a workaround, useful when loading a file generated by
   1169     a buggy zic.  (Problem and localtime.c fix reported by Bradley
   1170     White.)
   1171 
   1172     zdump -i now outputs non-hour numeric time zone abbreviations
   1173     without a colon, e.g., "+0530" rather than "+05:30".  This agrees
   1174     with zic %z and with common practice, and simplifies auditing of
   1175     zdump output.
   1176 
   1177     zdump is now buildable again with -DUSE_LTZ=0.
   1178     (Problem reported by Joseph Myers.)
   1179 
   1180     zdump.c now always includes private.h, to avoid code duplication
   1181     with private.h.  (Problem reported by Kees Dekker.)
   1182 
   1183     localtime.c no longer mishandles early or late timestamps
   1184     when TZ is set to a POSIX-style string that specifies DST.
   1185     (Problem reported by Kees Dekker.)
   1186 
   1187     date and strftime now cause %z to generate "-0000" instead of
   1188     "+0000" when the UT offset is zero and the time zone abbreviation
   1189     begins with "-".
   1190 
   1191   Changes to documentation and commentary
   1192 
   1193     The 'Theory' file now better documents choice of historical time
   1194     zone abbreviations.  (Problems reported by Michael Deckers.)
   1195 
   1196     tz-link.htm now covers leap smearing, which is popular in clouds.
   1197 
   1198 
   1199 Release 2016j - 2016-11-22 23:17:13 -0800
   1200 
   1201   Briefly: Saratov, Russia moves from +03 to +04 on 2016-12-04.
   1202 
   1203   Changes to future timestamps
   1204 
   1205     Saratov, Russia switches from +03 to +04 on 2016-12-04 at 02:00.
   1206     This hives off a new zone Europe/Saratov from Europe/Volgograd.
   1207     (Thanks to Yuri Konotopov and Stepan Golosunov.)
   1208 
   1209   Changes to past timestamps
   1210 
   1211     The new zone Asia/Atyrau for Atyra Region, Kazakhstan, is like
   1212     Asia/Aqtau except it switched from +05/+06 to +04/+05 in spring
   1213     1999, not fall 1994.  (Thanks to Stepan Golosunov.)
   1214 
   1215   Changes to past time zone abbreviations
   1216 
   1217     Asia/Gaza and Asia/Hebron now use "EEST", not "EET", to denote
   1218     summer time before 1948.  The old use of "EET" was a typo.
   1219 
   1220   Changes to code
   1221 
   1222     zic no longer mishandles file systems that lack hard links, fixing
   1223     bugs introduced in 2016g.  (Problems reported by Tom Lane.)
   1224     Also, when the destination already contains symbolic links, zic
   1225     should now work better on systems where the 'link' system call
   1226     does not follow symbolic links.
   1227 
   1228   Changes to documentation and commentary
   1229 
   1230     tz-link.htm now documents the relationship between release version
   1231     numbers and development-repository commit tags.  (Suggested by
   1232     Paul Koning.)
   1233 
   1234     The 'Theory' file now documents UT.
   1235 
   1236     iso3166.tab now accents "Curaao", and commentary now mentions
   1237     the names "Cabo Verde" and "Czechia".  (Thanks to Ji Boh.)
   1238 
   1239 
   1240 Release 2016i - 2016-11-01 23:19:52 -0700
   1241 
   1242   Briefly: Cyprus split into two time zones on 2016-10-30, and Tonga
   1243   reintroduces DST on 2016-11-06.
   1244 
   1245   Changes to future timestamps
   1246 
   1247     Pacific/Tongatapu begins DST on 2016-11-06 at 02:00, ending on
   1248     2017-01-15 at 03:00.  Assume future observances in Tonga will be
   1249     from the first Sunday in November through the third Sunday in
   1250     January, like Fiji.  (Thanks to Pulu Anau.)  Switch to numeric
   1251     time zone abbreviations for this zone.
   1252 
   1253   Changes to past and future timestamps
   1254 
   1255     Northern Cyprus is now +03 year round, causing a split in Cyprus
   1256     time zones starting 2016-10-30 at 04:00.  This creates a zone
   1257     Asia/Famagusta.  (Thanks to Even Scharning and Matt Johnson.)
   1258 
   1259     Antarctica/Casey switched from +08 to +11 on 2016-10-22.
   1260     (Thanks to Steffen Thorsen.)
   1261 
   1262   Changes to past timestamps
   1263 
   1264     Several corrections were made for pre-1975 timestamps in Italy.
   1265     These affect Europe/Malta, Europe/Rome, Europe/San_Marino, and
   1266     Europe/Vatican.
   1267 
   1268     First, the 1893-11-01 00:00 transition in Italy used the new UT
   1269     offset (+01), not the old (+00:49:56).  (Thanks to Michael
   1270     Deckers.)
   1271 
   1272     Second, rules for daylight saving in Italy were changed to agree
   1273     with Italy's National Institute of Metrological Research (INRiM)
   1274     except for 1944, as follows (thanks to Pierpaolo Bernardi, Brian
   1275     Inglis, and Michael Deckers):
   1276 
   1277       The 1916-06-03 transition was at 24:00, not 00:00.
   1278 
   1279       The 1916-10-01, 1919-10-05, and 1920-09-19 transitions were at
   1280       00:00, not 01:00.
   1281 
   1282       The 1917-09-30 and 1918-10-06 transitions were at 24:00, not
   1283       01:00.
   1284 
   1285       The 1944-09-17 transition was at 03:00, not 01:00.  This
   1286       particular change is taken from Italian law as INRiM's table,
   1287       (which says 02:00) appears to have a typo here.  Also, keep the
   1288       1944-04-03 transition for Europe/Rome, as Rome was controlled by
   1289       Germany then.
   1290 
   1291       The 1967-1970 and 1972-1974 fallback transitions were at 01:00,
   1292       not 00:00.
   1293 
   1294   Changes to code
   1295 
   1296     The code should now be buildable on AmigaOS merely by setting the
   1297     appropriate Makefile variables.  (From a patch by Carsten Larsen.)
   1298 
   1299 
   1300 Release 2016h - 2016-10-19 23:17:57 -0700
   1301 
   1302   Changes to future timestamps
   1303 
   1304     Asia/Gaza and Asia/Hebron end DST on 2016-10-29 at 01:00, not
   1305     2016-10-21 at 00:00.  (Thanks to Sharef Mustafa.)  Predict that
   1306     future fall transitions will be on the last Saturday of October
   1307     at 01:00, which is consistent with predicted spring transitions
   1308     on the last Saturday of March.  (Thanks to Tim Parenti.)
   1309 
   1310   Changes to past timestamps
   1311 
   1312     In Turkey, transitions in 1986-1990 were at 01:00 standard time
   1313     not at 02:00, and the spring 1994 transition was on March 20, not
   1314     March 27.  (Thanks to Kvan Yazan.)
   1315 
   1316   Changes to past and future time zone abbreviations
   1317 
   1318     Asia/Colombo now uses numeric time zone abbreviations like "+0530"
   1319     instead of alphabetic ones like "IST" and "LKT".  Various
   1320     English-language sources use "IST", "LKT" and "SLST", with no
   1321     working consensus.  (Usage of "SLST" mentioned by Sadika
   1322     Sumanapala.)
   1323 
   1324   Changes to code
   1325 
   1326     zic no longer mishandles relativizing file names when creating
   1327     symbolic links like /etc/localtime, when these symbolic links
   1328     are outside the usual directory hierarchy.  This fixes a bug
   1329     introduced in 2016g.  (Problem reported by Andreas Stieger.)
   1330 
   1331   Changes to build procedure
   1332 
   1333     New rules 'traditional_tarballs' and 'traditional_signatures' for
   1334     building just the traditional-format distribution.  (Requested by
   1335     Deborah Goldsmith.)
   1336 
   1337     The file 'version' is now put into the tzdata tarball too.
   1338     (Requested by Howard Hinnant.)
   1339 
   1340   Changes to documentation and commentary
   1341 
   1342     The 'Theory' file now has a section on interface stability.
   1343     (Requested by Paul Koning.)  It also mentions features like
   1344     tm_zone and localtime_rz that have long been supported by the
   1345     reference code.
   1346 
   1347     tz-link.htm has improved coverage of time zone boundaries suitable
   1348     for geolocation.  (Thanks to heads-ups from Evan Siroky and Matt
   1349     Johnson.)
   1350 
   1351     The US commentary now mentions Allen and the "day of two noons".
   1352 
   1353     The Fiji commentary mentions the government's 2016-10-03 press
   1354     release.  (Thanks to Raymond Kumar.)
   1355 
   1356 
   1357 Release 2016g - 2016-09-13 08:56:38 -0700
   1358 
   1359   Changes to future timestamps
   1360 
   1361     Turkey switched from EET/EEST (+02/+03) to permanent +03,
   1362     effective 2016-09-07.  (Thanks to Burak AYDIN.)  Use "+03" rather
   1363     than an invented abbreviation for the new time.
   1364 
   1365     New leap second 2016-12-31 23:59:60 UTC as per IERS Bulletin C 52.
   1366     (Thanks to Tim Parenti.)
   1367 
   1368   Changes to past timestamps
   1369 
   1370     For America/Los_Angeles, spring-forward transition times have been
   1371     corrected from 02:00 to 02:01 in 1948, and from 02:00 to 01:00 in
   1372     1950-1966.
   1373 
   1374     For zones using Soviet time on 1919-07-01, transitions to UT-based
   1375     time were at 00:00 UT, not at 02:00 local time.  The affected
   1376     zones are Europe/Kirov, Europe/Moscow, Europe/Samara, and
   1377     Europe/Ulyanovsk.  (Thanks to Alexander Belopolsky.)
   1378 
   1379   Changes to past and future time zone abbreviations
   1380 
   1381     The Factory zone now uses the time zone abbreviation -00 instead
   1382     of a long English-language string, as -00 is now the normal way to
   1383     represent an undefined time zone.
   1384 
   1385     Several zones in Antarctica and the former Soviet Union, along
   1386     with zones intended for ships at sea that cannot use POSIX TZ
   1387     strings, now use numeric time zone abbreviations instead of
   1388     invented or obsolete alphanumeric abbreviations.  The affected
   1389     zones are Antarctica/Casey, Antarctica/Davis,
   1390     Antarctica/DumontDUrville, Antarctica/Mawson, Antarctica/Rothera,
   1391     Antarctica/Syowa, Antarctica/Troll, Antarctica/Vostok,
   1392     Asia/Anadyr, Asia/Ashgabat, Asia/Baku, Asia/Bishkek, Asia/Chita,
   1393     Asia/Dushanbe, Asia/Irkutsk, Asia/Kamchatka, Asia/Khandyga,
   1394     Asia/Krasnoyarsk, Asia/Magadan, Asia/Omsk, Asia/Sakhalin,
   1395     Asia/Samarkand, Asia/Srednekolymsk, Asia/Tashkent, Asia/Tbilisi,
   1396     Asia/Ust-Nera, Asia/Vladivostok, Asia/Yakutsk, Asia/Yekaterinburg,
   1397     Asia/Yerevan, Etc/GMT-14, Etc/GMT-13, Etc/GMT-12, Etc/GMT-11,
   1398     Etc/GMT-10, Etc/GMT-9, Etc/GMT-8, Etc/GMT-7, Etc/GMT-6, Etc/GMT-5,
   1399     Etc/GMT-4, Etc/GMT-3, Etc/GMT-2, Etc/GMT-1, Etc/GMT+1, Etc/GMT+2,
   1400     Etc/GMT+3, Etc/GMT+4, Etc/GMT+5, Etc/GMT+6, Etc/GMT+7, Etc/GMT+8,
   1401     Etc/GMT+9, Etc/GMT+10, Etc/GMT+11, Etc/GMT+12, Europe/Kaliningrad,
   1402     Europe/Minsk, Europe/Samara, Europe/Volgograd, and
   1403     Indian/Kerguelen.  For Europe/Moscow the invented abbreviation MSM
   1404     was replaced by +05, whereas MSK and MSD were kept as they are not
   1405     our invention and are widely used.
   1406 
   1407   Changes to zone names
   1408 
   1409     Rename Asia/Rangoon to Asia/Yangon, with a backward compatibility link.
   1410     (Thanks to David Massoud.)
   1411 
   1412   Changes to code
   1413 
   1414     zic no longer generates binary files containing POSIX TZ-like
   1415     strings that disagree with the local time type after the last
   1416     explicit transition in the data.  This fixes a bug with
   1417     Africa/Casablanca and Africa/El_Aaiun in some year-2037 timestamps
   1418     on the reference platform.  (Thanks to Alexander Belopolsky for
   1419     reporting the bug and suggesting a way forward.)
   1420 
   1421     If the installed localtime and/or posixrules files are symbolic
   1422     links, zic now keeps them symbolic links when updating them, for
   1423     compatibility with platforms like OpenSUSE where other programs
   1424     configure these files as symlinks.
   1425 
   1426     zic now avoids hard linking to symbolic links, avoids some
   1427     unnecessary mkdir and stat system calls, and uses shorter file
   1428     names internally.
   1429 
   1430     zdump has a new -i option to generate transitions in a
   1431     more-compact but still human-readable format.  This option is
   1432     experimental, and the output format may change in future versions.
   1433     (Thanks to Jon Skeet for suggesting that an option was needed,
   1434     and thanks to Tim Parenti and Chris Rovick for further comments.)
   1435 
   1436   Changes to build procedure
   1437 
   1438     An experimental distribution format is available, in addition
   1439     to the traditional format which will continue to be distributed.
   1440     The new format is a tarball tzdb-VERSION.tar.lz with signature
   1441     file tzdb-VERSION.tar.lz.asc.  It unpacks to a top-level directory
   1442     tzdb-VERSION containing the code and data of the traditional
   1443     two-tarball format, along with extra data that may be useful.
   1444     (Thanks to Antonio Diaz Diaz, Oscar van Vlijmen, and many others
   1445     for comments about the experimental format.)
   1446 
   1447     The release version number is now more accurate in the usual case
   1448     where releases are built from a Git repository.  For example, if
   1449     23 commits and some working-file changes have been made since
   1450     release 2016g, the version number is now something like
   1451     '2016g-23-g50556e3-dirty' instead of the misleading '2016g'.
   1452     Tagged releases use the same version number format as before,
   1453     e.g., '2016g'.  To support the more-accurate version number, its
   1454     specification has moved from a line in the Makefile to a new
   1455     source file 'version'.
   1456 
   1457     The experimental distribution contains a file to2050.tzs that
   1458     contains what should be the output of 'zdump -i -c 2050' on
   1459     primary zones.  If this file is available, 'make check' now checks
   1460     that zdump generates this output.
   1461 
   1462     'make check_web' now works on Fedora-like distributions.
   1463 
   1464   Changes to documentation and commentary
   1465 
   1466     tzfile.5 now documents the new restriction on POSIX TZ-like
   1467     strings that is now implemented by zic.
   1468 
   1469     Comments now cite URLs for some 1917-1921 Russian DST decrees.
   1470     (Thanks to Alexander Belopolsky.)
   1471 
   1472     tz-link.htm mentions JuliaTime (thanks to Curtis Vogt) and Time4J
   1473     (thanks to Meno Hochschild) and ThreeTen-Extra, and its
   1474     description of Java 8 has been brought up to date (thanks to
   1475     Stephen Colebourne).  Its description of local time on Mars has
   1476     been updated to match current practice, and URLs have been updated
   1477     and some obsolete ones removed.
   1478 
   1479 
   1480 Release 2016f - 2016-07-05 16:26:51 +0200
   1481 
   1482   Changes affecting future timestamps
   1483 
   1484     The Egyptian government changed its mind on short notice, and
   1485     Africa/Cairo will not introduce DST starting 2016-07-07 after all.
   1486     (Thanks to Mina Samuel.)
   1487 
   1488     Asia/Novosibirsk switches from +06 to +07 on 2016-07-24 at 02:00.
   1489     (Thanks to Stepan Golosunov.)
   1490 
   1491   Changes to past and future timestamps
   1492 
   1493     Asia/Novokuznetsk and Asia/Novosibirsk now use numeric time zone
   1494     abbreviations instead of invented ones.
   1495 
   1496   Changes affecting past timestamps
   1497 
   1498     Europe/Minsk's 1992-03-29 spring-forward transition was at 02:00 not 00:00.
   1499     (Thanks to Stepan Golosunov.)
   1500 
   1501 
   1502 Release 2016e - 2016-06-14 08:46:16 -0700
   1503 
   1504   Changes affecting future timestamps
   1505 
   1506     Africa/Cairo observes DST in 2016 from July 7 to the end of October.
   1507     Guess October 27 and 24:00 transitions.  (Thanks to Steffen Thorsen.)
   1508     For future years, guess April's last Thursday to October's last
   1509     Thursday except for Ramadan.
   1510 
   1511   Changes affecting past timestamps
   1512 
   1513     Locations while uninhabited now use '-00', not 'zzz', as a
   1514     placeholder time zone abbreviation.  This is inspired by Internet
   1515     RFC 3339 and is more consistent with numeric time zone
   1516     abbreviations already used elsewhere.  The change affects several
   1517     arctic and antarctic locations, e.g., America/Cambridge_Bay before
   1518     1920 and Antarctica/Troll before 2005.
   1519 
   1520     Asia/Baku's 1992-09-27 transition from +04 (DST) to +04 (non-DST) was
   1521     at 03:00, not 23:00 the previous day.  (Thanks to Michael Deckers.)
   1522 
   1523   Changes to code
   1524 
   1525     zic now outputs a dummy transition at time 2**31 - 1 in zones
   1526     whose POSIX-style TZ strings contain a '<'.  This mostly works
   1527     around Qt bug 53071 <https://bugreports.qt.io/browse/QTBUG-53071>.
   1528     (Thanks to Zhanibek Adilbekov for reporting the Qt bug.)
   1529 
   1530   Changes affecting documentation and commentary
   1531 
   1532     tz-link.htm says why governments should give plenty of notice for
   1533     time zone or DST changes, and refers to Matt Johnson's blog post.
   1534 
   1535     tz-link.htm mentions Tzdata for Elixir.  (Thanks to Matt Johnson.)
   1536 
   1537 
   1538 Release 2016d - 2016-04-17 22:50:29 -0700
   1539 
   1540   Changes affecting future timestamps
   1541 
   1542     America/Caracas switches from -0430 to -04 on 2016-05-01 at 02:30.
   1543     (Thanks to Alexander Krivenyshev for the heads-up.)
   1544 
   1545     Asia/Magadan switches from +10 to +11 on 2016-04-24 at 02:00.
   1546     (Thanks to Alexander Krivenyshev and Matt Johnson.)
   1547 
   1548     New zone Asia/Tomsk, split off from Asia/Novosibirsk.  It covers
   1549     Tomsk Oblast, Russia, which switches from +06 to +07 on 2016-05-29
   1550     at 02:00.  (Thanks to Stepan Golosunov.)
   1551 
   1552   Changes affecting past timestamps
   1553 
   1554     New zone Europe/Kirov, split off from Europe/Volgograd.  It covers
   1555     Kirov Oblast, Russia, which switched from +04/+05 to +03/+04 on
   1556     1989-03-26 at 02:00, roughly a year after Europe/Volgograd made
   1557     the same change.  (Thanks to Stepan Golosunov.)
   1558 
   1559     Russia and nearby locations had daylight-saving transitions on
   1560     1992-03-29 at 02:00 and 1992-09-27 at 03:00, instead of on
   1561     1992-03-28 at 23:00 and 1992-09-26 at 23:00.  (Thanks to Stepan
   1562     Golosunov.)
   1563 
   1564     Many corrections to historical time in Kazakhstan from 1991
   1565     through 2005.  (Thanks to Stepan Golosunov.)  Replace Kazakhstan's
   1566     invented time zone abbreviations with numeric abbreviations.
   1567 
   1568   Changes to commentary
   1569 
   1570     Mention Internet RFCs 7808 (TZDIST) and 7809 (CalDAV time zone references).
   1571 
   1572 
   1573 Release 2016c - 2016-03-23 00:51:27 -0700
   1574 
   1575   Changes affecting future timestamps
   1576 
   1577     Azerbaijan no longer observes DST.  (Thanks to Steffen Thorsen.)
   1578 
   1579     Chile reverts from permanent to seasonal DST.  (Thanks to Juan
   1580     Correa for the heads-up, and to Tim Parenti for corrections.)
   1581     Guess that future transitions are August's and May's second
   1582     Saturdays at 24:00 mainland time.  Also, call the period from
   1583     2014-09-07 through 2016-05-14 daylight saving time instead of
   1584     standard time, as that seems more appropriate now.
   1585 
   1586   Changes affecting past timestamps
   1587 
   1588     Europe/Kaliningrad and Europe/Vilnius changed from +03/+04 to
   1589     +02/+03 on 1989-03-26, not 1991-03-31.  Europe/Volgograd changed
   1590     from +04/+05 to +03/+04 on 1988-03-27, not 1989-03-26.
   1591     (Thanks to Stepan Golosunov.)
   1592 
   1593   Changes to commentary
   1594 
   1595     Several updates and URLs for historical and proposed Russian changes.
   1596     (Thanks to Stepan Golosunov, Matt Johnson, and Alexander Krivenyshev.)
   1597 
   1598 
   1599 Release 2016b - 2016-03-12 17:30:14 -0800
   1600 
   1601   Compatibility note
   1602 
   1603     Starting with release 2016b, some data entries cause zic implementations
   1604     derived from tz releases 2005j through 2015e to issue warnings like
   1605     "time zone abbreviation differs from POSIX standard (+03)".
   1606     These warnings should not otherwise affect zic's output and can safely be
   1607     ignored on today's platforms, as the warnings refer to a restriction in
   1608     POSIX.1-1988 that was removed in POSIX.1-2001.  One way to suppress the
   1609     warnings is to upgrade to zic derived from tz releases 2015f and later.
   1610 
   1611   Changes affecting future timestamps
   1612 
   1613     New zones Europe/Astrakhan and Europe/Ulyanovsk for Astrakhan and
   1614     Ulyanovsk Oblasts, Russia, both of which will switch from +03 to +04 on
   1615     2016-03-27 at 02:00 local time.  They need distinct zones since their
   1616     post-1970 histories disagree.  New zone Asia/Barnaul for Altai Krai and
   1617     Altai Republic, Russia, which will switch from +06 to +07 on the same date
   1618     and local time.  The Astrakhan change is already official; the others have
   1619     passed the first reading in the State Duma and are extremely likely.
   1620     Also, Asia/Sakhalin moves from +10 to +11 on 2016-03-27 at 02:00.
   1621     (Thanks to Alexander Krivenyshev for the heads-up, and to Matt Johnson
   1622     and Stepan Golosunov for followup.)
   1623 
   1624     As a trial of a new system that needs less information to be made up,
   1625     the new zones use numeric time zone abbreviations like "+04"
   1626     instead of invented abbreviations like "ASTT".
   1627 
   1628     Haiti will not observe DST in 2016.  (Thanks to Jean Antoine via
   1629     Steffen Thorsen.)
   1630 
   1631     Palestine's spring-forward transition on 2016-03-26 is at 01:00, not 00:00.
   1632     (Thanks to Hannah Kreitem.) Guess future transitions will be March's last
   1633     Saturday at 01:00, not March's last Friday at 24:00.
   1634 
   1635   Changes affecting past timestamps
   1636 
   1637     Europe/Chisinau observed DST during 1990, and switched from +04 to
   1638     +03 at 1990-05-06 02:00, instead of switching from +03 to +02.
   1639     (Thanks to Stepan Golosunov.)
   1640 
   1641     1991 abbreviations in Europe/Samara should be SAMT/SAMST, not
   1642     KUYT/KUYST.  (Thanks to Stepan Golosunov.)
   1643 
   1644   Changes to code
   1645 
   1646     tzselect's diagnostics and checking, and checktab.awk's checking,
   1647     have been improved.  (Thanks to J William Piggott.)
   1648 
   1649     tzcode now builds under MinGW.  (Thanks to Ian Abbott and Esben Haabendal.)
   1650 
   1651     tzselect now tests Julian-date TZ settings more accurately.
   1652     (Thanks to J William Piggott.)
   1653 
   1654   Changes to commentary
   1655 
   1656     Comments in zone tables have been improved.  (Thanks to J William Piggott.)
   1657 
   1658     tzselect again limits its menu comments so that menus fit on a
   1659     2480 alphanumeric display.
   1660 
   1661     A new web page tz-how-to.html.  (Thanks to Bill Seymour.)
   1662 
   1663     In the Theory file, the description of possible time zone abbreviations in
   1664     tzdata has been cleaned up, as the old description was unclear and
   1665     inconsistent.  (Thanks to Alain Mouette for reporting the problem.)
   1666 
   1667 
   1668 Release 2016a - 2016-01-26 23:28:02 -0800
   1669 
   1670   Changes affecting future timestamps
   1671 
   1672     America/Cayman will not observe daylight saving this year after all.
   1673     Revert our guess that it would.  (Thanks to Matt Johnson.)
   1674 
   1675     Asia/Chita switches from +0800 to +0900 on 2016-03-27 at 02:00.
   1676     (Thanks to Alexander Krivenyshev.)
   1677 
   1678     Asia/Tehran now has DST predictions for the year 2038 and later,
   1679     to be March 21 00:00 to September 21 00:00.  This is likely better
   1680     than predicting no DST, albeit off by a day every now and then.
   1681 
   1682   Changes affecting past and future timestamps
   1683 
   1684     America/Metlakatla switched from PST all year to AKST/AKDT on
   1685     2015-11-01 at 02:00.  (Thanks to Steffen Thorsen.)
   1686 
   1687     America/Santa_Isabel has been removed, and replaced with a
   1688     backward compatibility link to America/Tijuana.  Its contents were
   1689     apparently based on a misreading of Mexican legislation.
   1690 
   1691   Changes affecting past timestamps
   1692 
   1693     Asia/Karachi's two transition times in 2002 were off by a minute.
   1694     (Thanks to Matt Johnson.)
   1695 
   1696   Changes affecting build procedure
   1697 
   1698     An installer can now combine leap seconds with use of the backzone file,
   1699     e.g., with 'make PACKRATDATA=backzone REDO=posix_right zones'.
   1700     The old 'make posix_packrat' rule is now marked as obsolescent.
   1701     (Thanks to Ian Abbott for an initial implementation.)
   1702 
   1703   Changes affecting documentation and commentary
   1704 
   1705     A new file LICENSE makes it easier to see that the code and data
   1706     are mostly public-domain.  (Thanks to James Knight.)  The three
   1707     non-public-domain files now use the current (3-clause) BSD license
   1708     instead of older versions of that license.
   1709 
   1710     tz-link.htm mentions the BDE library (thanks to Andrew Paprocki),
   1711     CCTZ (thanks to Tim Parenti), TimeJones.com, and has a new section
   1712     on editing tz source files (with a mention of Sublime zoneinfo,
   1713     thanks to Gilmore Davidson).
   1714 
   1715     The Theory and asia files now mention the 2015 book "The Global
   1716     Transformation of Time, 1870-1950", and cite a couple of reviews.
   1717 
   1718     The America/Chicago entry now documents the informal use of US
   1719     central time in Fort Pierre, South Dakota.  (Thanks to Rick
   1720     McDermid, Matt Johnson, and Steve Jones.)
   1721 
   1722 
   1723 Release 2015g - 2015-10-01 00:39:51 -0700
   1724 
   1725   Changes affecting future timestamps
   1726 
   1727     Turkey's 2015 fall-back transition is scheduled for Nov. 8, not Oct. 25.
   1728     (Thanks to Fatih.)
   1729 
   1730     Norfolk moves from +1130 to +1100 on 2015-10-04 at 02:00 local time.
   1731     (Thanks to Alexander Krivenyshev.)
   1732 
   1733     Fiji's 2016 fall-back transition is scheduled for January 17, not 24.
   1734     (Thanks to Ken Rylander.)
   1735 
   1736     Fort Nelson, British Columbia will not fall back on 2015-11-01.  It has
   1737     effectively been on MST (-0700) since it advanced its clocks on 2015-03-08.
   1738     New zone America/Fort_Nelson.  (Thanks to Matt Johnson.)
   1739 
   1740   Changes affecting past timestamps
   1741 
   1742     Norfolk observed DST from 1974-10-27 02:00 to 1975-03-02 02:00.
   1743 
   1744   Changes affecting code
   1745 
   1746     localtime no longer mishandles America/Anchorage after 2037.
   1747     (Thanks to Bradley White for reporting the bug.)
   1748 
   1749     On hosts with signed 32-bit time_t, localtime no longer mishandles
   1750     Pacific/Fiji after 2038-01-16 14:00 UTC.
   1751 
   1752     The localtime module allows the variables 'timezone', 'daylight',
   1753     and 'altzone' to be in common storage shared with other modules,
   1754     and declares them in case the system <time.h> does not.
   1755     (Problems reported by Kees Dekker.)
   1756 
   1757     On platforms with tm_zone, strftime.c now assumes it is not NULL.
   1758     This simplifies the code and is consistent with zdump.c.
   1759     (Problem reported by Christos Zoulas.)
   1760 
   1761   Changes affecting documentation
   1762 
   1763    The tzfile man page now documents that transition times denote the
   1764    starts (not the ends) of the corresponding time periods.
   1765    (Ambiguity reported by Bill Seymour.)
   1766 
   1767 
   1768 Release 2015f - 2015-08-10 18:06:56 -0700
   1769 
   1770   Changes affecting future timestamps
   1771 
   1772     North Korea switches to +0830 on 2015-08-15.  (Thanks to Steffen Thorsen.)
   1773     The abbreviation remains "KST".  (Thanks to Robert Elz.)
   1774 
   1775     Uruguay no longer observes DST.  (Thanks to Steffen Thorsen
   1776     and Pablo Camargo.)
   1777 
   1778   Changes affecting past and future timestamps
   1779 
   1780     Moldova starts and ends DST at 00:00 UTC, not at 01:00 UTC.
   1781     (Thanks to Roman Tudos.)
   1782 
   1783   Changes affecting data format and code
   1784 
   1785     zic's '-y YEARISTYPE' option is no longer documented.  The TYPE
   1786     field of a Rule line should now be '-'; the old values 'even',
   1787     'odd', 'uspres', 'nonpres', 'nonuspres' were already undocumented.
   1788     Although the implementation has not changed, these features do not
   1789     work in the default installation, they are not used in the data,
   1790     and they are now considered obsolescent.
   1791 
   1792     zic now checks that two rules don't take effect at the same time.
   1793     (Thanks to Jon Skeet and Arthur David Olson.)  Constraints on
   1794     simultaneity are now documented.
   1795 
   1796     The two characters '%z' in a zone format now stand for the UT
   1797     offset, e.g., '-07' for seven hours behind UT and '+0530' for
   1798     five hours and thirty minutes ahead.  This better supports time
   1799     zone abbreviations conforming to POSIX.1-2001 and later.
   1800 
   1801   Changes affecting installed data files
   1802 
   1803     Comments for America/Halifax and America/Glace_Bay have been improved.
   1804     (Thanks to Brian Inglis.)
   1805 
   1806     Data entries have been simplified for Atlantic/Canary, Europe/Simferopol,
   1807     Europe/Sofia, and Europe/Tallinn.  This yields slightly smaller
   1808     installed data files for Europe/Simferopol and Europe/Tallinn.
   1809     It does not affect timestamps.  (Thanks to Howard Hinnant.)
   1810 
   1811   Changes affecting code
   1812 
   1813     zdump and zic no longer warn about valid time zone abbreviations
   1814     like '-05'.
   1815 
   1816     Some Visual Studio 2013 warnings have been suppressed.
   1817     (Thanks to Kees Dekker.)
   1818 
   1819     'date' no longer sets the time of day and its -a, -d, -n and -t
   1820     options have been removed.  Long obsolescent, the implementation
   1821     of these features had porting problems.  Builders no longer need
   1822     to configure HAVE_ADJTIME, HAVE_SETTIMEOFDAY, or HAVE_UTMPX_H.
   1823     (Thanks to Kees Dekker for pointing out the problem.)
   1824 
   1825   Changes affecting documentation
   1826 
   1827     The Theory file mentions naming issues earlier, as these seem to be
   1828     poorly publicized (thanks to Gilmore Davidson for reporting the problem).
   1829 
   1830     tz-link.htm mentions Time Zone Database Parser (thanks to Howard Hinnant).
   1831 
   1832     Mention that Herbert Samuel introduced the term "Summer Time".
   1833 
   1834 
   1835 Release 2015e - 2015-06-13 10:56:02 -0700
   1836 
   1837   Changes affecting future timestamps
   1838 
   1839     Morocco will suspend DST from 2015-06-14 03:00 through 2015-07-19 02:00,
   1840     not 06-13 and 07-18 as we had guessed.  (Thanks to Milamber.)
   1841 
   1842     Assume Cayman Islands will observe DST starting next year, using US rules.
   1843     Although it isn't guaranteed, it is the most likely.
   1844 
   1845   Changes affecting data format
   1846 
   1847     The file 'iso3166.tab' now uses UTF-8, so that its entries can better
   1848     spell the names of land Islands, Cte d'Ivoire, and Runion.
   1849 
   1850   Changes affecting code
   1851 
   1852     When displaying data, tzselect converts it to the current locale's
   1853     encoding if the iconv command works.  (Problem reported by random832.)
   1854 
   1855     tzselect no longer mishandles Dominica, fixing a bug introduced
   1856     in Release 2014f.  (Problem reported by Owen Leibman.)
   1857 
   1858     zic -l no longer fails when compiled with -DTZDEFAULT=\"/etc/localtime\".
   1859     This fixes a bug introduced in Release 2014f.
   1860     (Problem reported by Leonardo Chiquitto.)
   1861 
   1862 
   1863 Release 2015d - 2015-04-24 08:09:46 -0700
   1864 
   1865   Changes affecting future timestamps
   1866 
   1867     Egypt will not observe DST in 2015 and will consider canceling it
   1868     permanently.  For now, assume no DST indefinitely.
   1869     (Thanks to Ahmed Nazmy and Tim Parenti.)
   1870 
   1871   Changes affecting past timestamps
   1872 
   1873     America/Whitehorse switched from UT -09 to -08 on 1967-05-28, not
   1874     1966-07-01.  Also, Yukon's time zone history is documented better.
   1875     (Thanks to Brian Inglis and Dennis Ferguson.)
   1876 
   1877   Change affecting past and future time zone abbreviations
   1878 
   1879     The abbreviations for Hawaii-Aleutian standard and daylight times
   1880     have been changed from HAST/HADT to HST/HDT, as per US Government
   1881     Printing Office style.  This affects only America/Adak since 1983,
   1882     as America/Honolulu was already using the new style.
   1883 
   1884   Changes affecting code
   1885 
   1886    zic has some minor performance improvements.
   1887 
   1888 
   1889 Release 2015c - 2015-04-11 08:55:55 -0700
   1890 
   1891   Changes affecting future timestamps
   1892 
   1893     Egypt's spring-forward transition is at 24:00 on April's last Thursday,
   1894     not 00:00 on April's last Friday.  2015's transition will therefore be on
   1895     Thursday, April 30 at 24:00, not Friday, April 24 at 00:00.  Similar fixes
   1896     apply to 2026, 2037, 2043, etc.  (Thanks to Steffen Thorsen.)
   1897 
   1898   Changes affecting past timestamps
   1899 
   1900     The following changes affect some pre-1991 Chile-related timestamps
   1901     in America/Santiago, Antarctica/Palmer, and Pacific/Easter.
   1902 
   1903       The 1910 transition was January 10, not January 1.
   1904 
   1905       The 1918 transition was September 10, not September 1.
   1906 
   1907       The UT -04 time observed from 1932 to 1942 is now considered to
   1908       be standard time, not year-round DST.
   1909 
   1910       Santiago observed DST (UT -03) from 1946-07-15 through
   1911       1946-08-31, then reverted to standard time, then switched to -05
   1912       on 1947-04-01.
   1913 
   1914       Assume transitions before 1968 were at 00:00, since we have no data
   1915       saying otherwise.
   1916 
   1917       The spring 1988 transition was 1988-10-09, not 1988-10-02.
   1918       The fall 1990 transition was 1990-03-11, not 1990-03-18.
   1919 
   1920       Assume no UT offset change for Pacific/Easter on 1890-01-01,
   1921       and omit all transitions on Pacific/Easter from 1942 through 1946
   1922       since we have no data suggesting that they existed.
   1923 
   1924     One more zone has been turned into a link, as it differed
   1925     from an existing zone only for older timestamps.  As usual,
   1926     this change affects UT offsets in pre-1970 timestamps only.
   1927     The zone's old contents have been moved to the 'backzone' file.
   1928     The affected zone is America/Montreal.
   1929 
   1930   Changes affecting commentary
   1931 
   1932     Mention the TZUpdater tool.
   1933 
   1934     Mention "The Time Now".  (Thanks to Brandon Ramsey.)
   1935 
   1936 
   1937 Release 2015b - 2015-03-19 23:28:11 -0700
   1938 
   1939   Changes affecting future timestamps
   1940 
   1941     Mongolia will start observing DST again this year, from the last
   1942     Saturday in March at 02:00 to the last Saturday in September at 00:00.
   1943     (Thanks to Ganbold Tsagaankhuu.)
   1944 
   1945     Palestine will start DST on March 28, not March 27.  Also,
   1946     correct the fall 2014 transition from September 26 to October 24.
   1947     Adjust future predictions accordingly.  (Thanks to Steffen Thorsen.)
   1948 
   1949   Changes affecting past timestamps
   1950 
   1951     The 1982 zone shift in Pacific/Easter has been corrected, fixing a 2015a
   1952     regression.  (Thanks to Stuart Bishop for reporting the problem.)
   1953 
   1954     Some more zones have been turned into links, when they differed
   1955     from existing zones only for older timestamps.  As usual,
   1956     these changes affect UT offsets in pre-1970 timestamps only.
   1957     Their old contents have been moved to the 'backzone' file.
   1958     The affected zones are: America/Antigua, America/Cayman,
   1959     Pacific/Midway, and Pacific/Saipan.
   1960 
   1961   Changes affecting time zone abbreviations
   1962 
   1963     Correct the 1992-2010 DST abbreviation in Volgograd from "MSK" to "MSD".
   1964     (Thanks to Hank W.)
   1965 
   1966   Changes affecting code
   1967 
   1968     Fix integer overflow bug in reference 'mktime' implementation.
   1969     (Problem reported by Jrg Richter.)
   1970 
   1971     Allow -Dtime_tz=time_t compilations, and allow -Dtime_tz=... libraries
   1972     to be used in the same executable as standard-library time_t functions.
   1973     (Problems reported by Bradley White.)
   1974 
   1975   Changes affecting commentary
   1976 
   1977     Cite the recent Mexican decree changing Quintana Roo's time zone.
   1978     (Thanks to Carlos Ral Perasso.)
   1979 
   1980     Likewise for the recent Chilean decree.  (Thanks to Eduardo Romero Urra.)
   1981 
   1982     Update info about Mars time.
   1983 
   1984 
   1985 Release 2015a - 2015-01-29 22:35:20 -0800
   1986 
   1987   Changes affecting future timestamps
   1988 
   1989     The Mexican state of Quintana Roo, represented by America/Cancun,
   1990     will shift from Central Time with DST to Eastern Time without DST
   1991     on 2015-02-01 at 02:00.  (Thanks to Steffen Thorsen and Gwillim Law.)
   1992 
   1993     Chile will not change clocks in April or thereafter; its new standard time
   1994     will be its old daylight saving time.  This affects America/Santiago,
   1995     Pacific/Easter, and Antarctica/Palmer.  (Thanks to Juan Correa.)
   1996 
   1997     New leap second 2015-06-30 23:59:60 UTC as per IERS Bulletin C 49.
   1998     (Thanks to Tim Parenti.)
   1999 
   2000   Changes affecting past timestamps
   2001 
   2002     Iceland observed DST in 1919 and 1921, and its 1939 fallback
   2003     transition was Oct. 29, not Nov. 29.  Remove incorrect data from
   2004     Shanks about time in Iceland between 1837 and 1908.
   2005 
   2006     Some more zones have been turned into links, when they differed
   2007     from existing zones only for older timestamps.  As usual,
   2008     these changes affect UT offsets in pre-1970 timestamps only.
   2009     Their old contents have been moved to the 'backzone' file.
   2010     The affected zones are: Asia/Aden, Asia/Bahrain, Asia/Kuwait,
   2011     and Asia/Muscat.
   2012 
   2013   Changes affecting code
   2014 
   2015     tzalloc now scrubs time zone abbreviations compatibly with the way
   2016     that tzset always has, by replacing invalid bytes with '_' and by
   2017     shortening too-long abbreviations.
   2018 
   2019     tzselect ports to POSIX awk implementations, no longer mishandles
   2020     POSIX TZ settings when GNU awk is used, and reports POSIX TZ
   2021     settings to the user.  (Thanks to Stefan Kuhn.)
   2022 
   2023   Changes affecting build procedure
   2024 
   2025     'make check' now checks for links to links in the data.
   2026     One such link (for Africa/Asmera) has been fixed.
   2027     (Thanks to Stephen Colebourne for pointing out the problem.)
   2028 
   2029   Changes affecting commentary
   2030 
   2031     The leapseconds file commentary now mentions the expiration date.
   2032     (Problem reported by Martin Burnicki.)
   2033 
   2034     Update Mexican Library of Congress URL.
   2035 
   2036 
   2037 Release 2014j - 2014-11-10 17:37:11 -0800
   2038 
   2039   Changes affecting current and future timestamps
   2040 
   2041     Turks & Caicos' switch from US eastern time to UT -04 year-round
   2042     did not occur on 2014-11-02 at 02:00.  It's currently scheduled
   2043     for 2015-11-01 at 02:00.  (Thanks to Chris Walton.)
   2044 
   2045   Changes affecting past timestamps
   2046 
   2047     Many pre-1989 timestamps have been corrected for Asia/Seoul and
   2048     Asia/Pyongyang, based on sources for the Korean-language Wikipedia
   2049     entry for time in Korea.  (Thanks to Sanghyuk Jung.)  Also, no
   2050     longer guess that Pyongyang mimicked Seoul time after World War II,
   2051     as this is politically implausible.
   2052 
   2053     Some more zones have been turned into links, when they differed
   2054     from existing zones only for older timestamps.  As usual,
   2055     these changes affect UT offsets in pre-1970 timestamps only.
   2056     Their old contents have been moved to the 'backzone' file.
   2057     The affected zones are: Africa/Addis_Ababa, Africa/Asmara,
   2058     Africa/Dar_es_Salaam, Africa/Djibouti, Africa/Kampala,
   2059     Africa/Mogadishu, Indian/Antananarivo, Indian/Comoro, and
   2060     Indian/Mayotte.
   2061 
   2062   Changes affecting commentary
   2063 
   2064     The commentary is less enthusiastic about Shanks as a source,
   2065     and is more careful to distinguish UT from UTC.
   2066 
   2067 
   2068 Release 2014i - 2014-10-21 22:04:57 -0700
   2069 
   2070   Changes affecting future timestamps
   2071 
   2072     Pacific/Fiji will observe DST from 2014-11-02 02:00 to 2015-01-18 03:00.
   2073     (Thanks to Ken Rylander for the heads-up.)  Guess that future
   2074     years will use a similar pattern.
   2075 
   2076     A new Zone Pacific/Bougainville, for the part of Papua New Guinea
   2077     that plans to switch from UT +10 to +11 on 2014-12-28 at 02:00.
   2078     (Thanks to Kiley Walbom for the heads-up.)
   2079 
   2080   Changes affecting time zone abbreviations
   2081 
   2082     Since Belarus is not changing its clocks even though Moscow is,
   2083     the time zone abbreviation in Europe/Minsk is changing from FET
   2084     to its more-traditional value MSK on 2014-10-26 at 01:00.
   2085     (Thanks to Alexander Bokovoy for the heads-up about Belarus.)
   2086 
   2087     The new abbreviation IDT stands for the pre-1976 use of UT +08 in
   2088     Indochina, to distinguish it better from ICT (+07).
   2089 
   2090   Changes affecting past timestamps
   2091 
   2092     Many timestamps have been corrected for Asia/Ho_Chi_Minh before 1976
   2093     (thanks to Trn Ngc Qun for an indirect pointer to Trn Tin Bnh's
   2094     authoritative book).  Asia/Ho_Chi_Minh has been added to
   2095     zone1970.tab, to give tzselect users in Vietnam two choices,
   2096     since north and south Vietnam disagreed after our 1970 cutoff.
   2097 
   2098     Asia/Phnom_Penh and Asia/Vientiane have been turned into links, as
   2099     they differed from existing zones only for older timestamps.  As
   2100     usual, these changes affect pre-1970 timestamps only.  Their old
   2101     contents have been moved to the 'backzone' file.
   2102 
   2103   Changes affecting code
   2104 
   2105     The time-related library functions now set errno on failure, and
   2106     some crashes in the new tzalloc-related library functions have
   2107     been fixed.  (Thanks to Christos Zoulas for reporting most of
   2108     these problems and for suggesting fixes.)
   2109 
   2110     If USG_COMPAT is defined and the requested timestamp is standard time,
   2111     the tz library's localtime and mktime functions now set the extern
   2112     variable timezone to a value appropriate for that timestamp; and
   2113     similarly for ALTZONE, daylight saving time, and the altzone variable.
   2114     This change is a companion to the tzname change in 2014h, and is
   2115     designed to make timezone and altzone more compatible with tzname.
   2116 
   2117     The tz library's functions now set errno to EOVERFLOW if they fail
   2118     because the result cannot be represented.  ctime and ctime_r now
   2119     return NULL and set errno when a timestamp is out of range, rather
   2120     than having undefined behavior.
   2121 
   2122     Some bugs associated with the new 2014g functions have been fixed.
   2123     This includes a bug that largely incapacitated the new functions
   2124     time2posix_z and posix2time_z.  (Thanks to Christos Zoulas.)
   2125     It also includes some uses of uninitialized variables after tzalloc.
   2126     The new code uses the standard type 'ssize_t', which the Makefile
   2127     now gives porting advice about.
   2128 
   2129   Changes affecting commentary
   2130 
   2131     Updated URLs for NRC Canada (thanks to Matt Johnson and Brian Inglis).
   2132 
   2133 
   2134 Release 2014h - 2014-09-25 18:59:03 -0700
   2135 
   2136   Changes affecting past timestamps
   2137 
   2138     America/Jamaica's 1974 spring-forward transition was Jan. 6, not Apr. 28.
   2139 
   2140     Shanks says Asia/Novokuznetsk switched from LMT (not "NMT") on 1924-05-01,
   2141     not 1920-01-06.  The old entry was based on a misinterpretation of Shanks.
   2142 
   2143     Some more zones have been turned into links, when they differed
   2144     from existing zones only for older timestamps.  As usual,
   2145     these changes affect UT offsets in pre-1970 timestamps only.
   2146     Their old contents have been moved to the 'backzone' file.
   2147     The affected zones are: Africa/Blantyre, Africa/Bujumbura,
   2148     Africa/Gaborone, Africa/Harare, Africa/Kigali, Africa/Lubumbashi,
   2149     Africa/Lusaka, Africa/Maseru, and Africa/Mbabane.
   2150 
   2151   Changes affecting code
   2152 
   2153     zdump -V and -v now output gmtoff= values on all platforms,
   2154     not merely on platforms defining TM_GMTOFF.
   2155 
   2156     The tz library's localtime and mktime functions now set tzname to a value
   2157     appropriate for the requested timestamp, and zdump now uses this
   2158     on platforms not defining TM_ZONE, fixing a 2014g regression.
   2159     (Thanks to Tim Parenti for reporting the problem.)
   2160 
   2161     The tz library no longer sets tzname if localtime or mktime fails.
   2162 
   2163     zdump -c no longer mishandles transitions near year boundaries.
   2164     (Thanks to Tim Parenti for reporting the problem.)
   2165 
   2166     An access to uninitialized data has been fixed.
   2167     (Thanks to Jrg Richter for reporting the problem.)
   2168 
   2169     When THREAD_SAFE is defined, the code ports to the C11 memory model.
   2170     A memory leak has been fixed if ALL_STATE and THREAD_SAFE are defined
   2171     and two threads race to initialize data used by gmtime-like functions.
   2172     (Thanks to Andy Heninger for reporting the problems.)
   2173 
   2174   Changes affecting build procedure
   2175 
   2176     'make check' now checks better for properly-sorted data.
   2177 
   2178   Changes affecting documentation and commentary
   2179 
   2180     zdump's gmtoff=N output is now documented, and its isdst=D output
   2181     is now documented to possibly output D values other than 0 or 1.
   2182 
   2183     zdump -c's treatment of years is now documented to use the
   2184     Gregorian calendar and Universal Time without leap seconds,
   2185     and its behavior at cutoff boundaries is now documented better.
   2186     (Thanks to Arthur David Olson and Tim Parenti for reporting the problems.)
   2187 
   2188     Programs are now documented to use the proleptic Gregorian calendar.
   2189     (Thanks to Alan Barrett for the suggestion.)
   2190 
   2191     Fractional-second GMT offsets have been documented for civil time
   2192     in 19th-century Chennai, Jakarta, and New York.
   2193 
   2194 
   2195 Release 2014g - 2014-08-28 12:31:23 -0700
   2196 
   2197   Changes affecting future timestamps
   2198 
   2199     Turks & Caicos is switching from US eastern time to UT -04
   2200     year-round, modeled as a switch on 2014-11-02 at 02:00.
   2201     [As noted in 2014j, this switch was later delayed.]
   2202 
   2203   Changes affecting past timestamps
   2204 
   2205     Time in Russia or the USSR before 1926 or so has been corrected by
   2206     a few seconds in the following zones: Asia/Irkutsk,
   2207     Asia/Krasnoyarsk, Asia/Omsk, Asia/Samarkand, Asia/Tbilisi,
   2208     Asia/Vladivostok, Asia/Yakutsk, Europe/Riga, Europe/Samara.  For
   2209     Asia/Yekaterinburg the correction is a few minutes.  (Thanks to
   2210     Vladimir Karpinsky.)
   2211 
   2212     The Portuguese decree of 1911-05-26 took effect on 1912-01-01.
   2213     This affects 1911 timestamps in Africa/Bissau, Africa/Luanda,
   2214     Atlantic/Azores, and Atlantic/Madeira.  Also, Lisbon's pre-1912
   2215     GMT offset was -0:36:45 (rounded from -0:36:44.68), not -0:36:32.
   2216     (Thanks to Stephen Colebourne for pointing to the decree.)
   2217 
   2218     Asia/Dhaka ended DST on 2009-12-31 at 24:00, not 23:59.
   2219 
   2220     A new file 'backzone' contains data which may appeal to
   2221     connoisseurs of old timestamps, although it is out of scope for
   2222     the tz database, is often poorly sourced, and contains some data
   2223     that is known to be incorrect.  The new file is not recommended
   2224     for ordinary use and its entries are not installed by default.
   2225     (Thanks to Lester Caine for the high-quality Jersey, Guernsey, and
   2226     Isle of Man entries.)
   2227 
   2228     Some more zones have been turned into links, when they differed
   2229     from existing zones only for older timestamps.  As usual,
   2230     these changes affect UT offsets in pre-1970 timestamps only.
   2231     Their old contents have been moved to the 'backzone' file.
   2232     The affected zones are: Africa/Bangui, Africa/Brazzaville,
   2233     Africa/Douala, Africa/Kinshasa, Africa/Libreville, Africa/Luanda,
   2234     Africa/Malabo, Africa/Niamey, and Africa/Porto-Novo.
   2235 
   2236   Changes affecting code
   2237 
   2238     Unless NETBSD_INSPIRED is defined to 0, the tz library now
   2239     supplies functions for creating and using objects that represent
   2240     timezones. The new functions are tzalloc, tzfree, localtime_rz,
   2241     mktime_z, and (if STD_INSPIRED is also defined) posix2time_z and
   2242     time2posix_z.  They are intended for performance: for example,
   2243     localtime_rz (unlike localtime_r) is trivially thread-safe without
   2244     locking.  (Thanks to Christos Zoulas for proposing NetBSD-inspired
   2245     functions, and to Alan Barrett and Jonathan Lennox for helping to
   2246     debug the change.)
   2247 
   2248     zdump now builds with the tz library unless USE_LTZ is defined to 0,
   2249     This lets zdump use tz features even if the system library lacks them.
   2250     To build zdump with the system library, use 'make CFLAGS=-DUSE_LTZ=0
   2251     TZDOBJS=zdump.o CHECK_TIME_T_ALTERNATIVES='.
   2252 
   2253     zdump now uses localtime_rz if available, as it's significantly faster,
   2254     and it can help zdump better diagnose invalid timezone names.
   2255     Define HAVE_LOCALTIME_RZ to 0 to suppress this.  HAVE_LOCALTIME_RZ
   2256     defaults to 1 if NETBSD_INSPIRED && USE_LTZ.  When localtime_rz is
   2257     not available, zdump now uses localtime_r and tzset if available,
   2258     as this is a bit cleaner and faster than plain localtime.  Compile
   2259     with -DHAVE_LOCALTIME_R=0 and/or -DHAVE_TZSET=0 if your system
   2260     lacks these two functions.
   2261 
   2262     If THREAD_SAFE is defined to 1, the tz library is now thread-safe.
   2263     Although not needed for tz's own applications, which are single-threaded,
   2264     this supports POSIX better if the tz library is used in multithreaded apps.
   2265 
   2266     Some crashes have been fixed when zdump or the tz library is given
   2267     invalid or outlandish input.
   2268 
   2269     The tz library no longer mishandles leap seconds on platforms with
   2270     unsigned time_t in timezones that lack ordinary transitions after 1970.
   2271 
   2272     The tz code now attempts to infer TM_GMTOFF and TM_ZONE if not
   2273     already defined, to make it easier to configure on common platforms.
   2274     Define NO_TM_GMTOFF and NO_TM_ZONE to suppress this.
   2275 
   2276     Unless the new macro UNINIT_TRAP is defined to 1, the tz code now
   2277     assumes that reading uninitialized memory yields garbage values
   2278     but does not cause other problems such as traps.
   2279 
   2280     If TM_GMTOFF is defined and UNINIT_TRAP is 0, mktime is now
   2281     more likely to guess right for ambiguous timestamps near
   2282     transitions where tm_isdst does not change.
   2283 
   2284     If HAVE_STRFTIME_L is defined to 1, the tz library now defines
   2285     strftime_l for compatibility with recent versions of POSIX.
   2286     Only the C locale is supported, though.  HAVE_STRFTIME_L defaults
   2287     to 1 on recent POSIX versions, and to 0 otherwise.
   2288 
   2289     tzselect -c now uses a hybrid distance measure that works better
   2290     in Africa.  (Thanks to Alan Barrett for noting the problem.)
   2291 
   2292     The C source code now ports to NetBSD when GCC_DEBUG_FLAGS is used,
   2293     or when time_tz is defined.
   2294 
   2295     When HAVE_UTMPX_H is set the 'date' command now builds on systems
   2296     whose <utmpx.h> file does not define WTMPX_FILE, and when setting
   2297     the date it updates the wtmpx file if _PATH_WTMPX is defined.
   2298     This affects GNU/Linux and similar systems.
   2299 
   2300     For easier maintenance later, some C code has been simplified,
   2301     some lint has been removed, and the code has been tweaked so that
   2302     plain 'make' is more likely to work.
   2303 
   2304     The C type 'bool' is now used for boolean values, instead of 'int'.
   2305 
   2306     The long-obsolete LOCALE_HOME code has been removed.
   2307 
   2308     The long-obsolete 'gtime' function has been removed.
   2309 
   2310   Changes affecting build procedure
   2311 
   2312     'zdump' no longer links in ialloc.o, as it's not needed.
   2313 
   2314     'make check_time_t_alternatives' no longer assumes GNU diff.
   2315 
   2316   Changes affecting distribution tarballs
   2317 
   2318     The files checktab.awk and zoneinfo2tdf.pl are now distributed in
   2319     the tzdata tarball instead of the tzcode tarball, since they help
   2320     maintain the data.  The NEWS and Theory files are now also
   2321     distributed in the tzdata tarball, as they're relevant for data.
   2322     (Thanks to Alan Barrett for pointing this out.)  Also, the
   2323     leapseconds.awk file is no longer distributed in the tzcode
   2324     tarball, since it belongs in the tzdata tarball (where 2014f
   2325     inadvertently also distributed it).
   2326 
   2327   Changes affecting documentation and commentary
   2328 
   2329     A new file CONTRIBUTING is distributed.  (Thanks to Tim Parenti for
   2330     suggesting a CONTRIBUTING file, and to Tony Finch and Walter Harms
   2331     for debugging it.)
   2332 
   2333     The man pages have been updated to use function prototypes,
   2334     to document thread-safe variants like localtime_r, and to document
   2335     the NetBSD-inspired functions tzalloc, tzfree, localtime_rz, and
   2336     mktime_z.
   2337 
   2338     The fields in Link lines have been renamed to be more descriptive
   2339     and more like the parameters of 'ln'.  LINK-FROM has become TARGET,
   2340     and LINK-TO has become LINK-NAME.
   2341 
   2342     tz-link.htm mentions the IETF's tzdist working group; Windows
   2343     Runtime etc. (thanks to Matt Johnson); and HP-UX's tztab.
   2344 
   2345     Some broken URLs have been fixed in the commentary.  (Thanks to
   2346     Lester Caine.)
   2347 
   2348     Commentary about Philippines DST has been updated, and commentary
   2349     on pre-1970 time in India has been added.
   2350 
   2351 
   2352 Release 2014f - 2014-08-05 17:42:36 -0700
   2353 
   2354   Changes affecting future timestamps
   2355 
   2356     Russia will subtract an hour from most of its time zones on 2014-10-26
   2357     at 02:00 local time.  (Thanks to Alexander Krivenyshev.)
   2358     There are a few exceptions: Magadan Oblast (Asia/Magadan) and Zabaykalsky
   2359     Krai are subtracting two hours; conversely, Chukotka Autonomous Okrug
   2360     (Asia/Anadyr), Kamchatka Krai (Asia/Kamchatka), Kemerovo Oblast
   2361     (Asia/Novokuznetsk), and the Samara Oblast and the Udmurt Republic
   2362     (Europe/Samara) are not changing their clocks.  The changed zones are
   2363     Europe/Kaliningrad, Europe/Moscow, Europe/Simferopol, Europe/Volgograd,
   2364     Asia/Yekaterinburg, Asia/Omsk, Asia/Novosibirsk, Asia/Krasnoyarsk,
   2365     Asia/Irkutsk, Asia/Yakutsk, Asia/Vladivostok, Asia/Khandyga,
   2366     Asia/Sakhalin, and Asia/Ust-Nera; Asia/Magadan will have two hours
   2367     subtracted; and Asia/Novokuznetsk's time zone abbreviation is affected,
   2368     but not its UTC offset.  Two zones are added: Asia/Chita (split
   2369     from Asia/Yakutsk, and also with two hours subtracted) and
   2370     Asia/Srednekolymsk (split from Asia/Magadan, but with only one hour
   2371     subtracted).  (Thanks to Tim Parenti for much of the above.)
   2372 
   2373   Changes affecting time zone abbreviations
   2374 
   2375     Australian eastern time zone abbreviations are now AEST/AEDT not EST,
   2376     and similarly for the other Australian zones.  That is, for eastern
   2377     standard and daylight saving time the abbreviations are AEST and AEDT
   2378     instead of the former EST for both; similarly, ACST/ACDT, ACWST/ACWDT,
   2379     and AWST/AWDT are now used instead of the former CST, CWST, and WST.
   2380     This change does not affect UT offsets, only time zone abbreviations.
   2381     (Thanks to Rich Tibbett and many others.)
   2382 
   2383     Asia/Novokuznetsk shifts from NOVT to KRAT (remaining on UT +07)
   2384     effective 2014-10-26 at 02:00 local time.
   2385 
   2386     The time zone abbreviation for Xinjiang Time (observed in rmqi)
   2387     has been changed from URUT to XJT.  (Thanks to Luther Ma.)
   2388 
   2389     Prefer MSK/MSD for Moscow time in Russia, even in other cities.
   2390     Similarly, prefer EET/EEST for eastern European time in Russia.
   2391 
   2392     Change time zone abbreviations in (western) Samoa to use "ST" and
   2393     "DT" suffixes, as this is more likely to match common practice.
   2394     Prefix "W" to (western) Samoa time when its standard-time offset
   2395     disagrees with that of American Samoa.
   2396 
   2397     America/Metlakatla now uses PST, not MeST, to abbreviate its time zone.
   2398 
   2399     Time zone abbreviations have been updated for Japan's two time
   2400     zones used 1896-1937.  JWST now stands for Western Standard
   2401     Time, and JCST for Central Standard Time (formerly this was CJT).
   2402     These abbreviations are now used for time in Korea, Taiwan,
   2403     and Sakhalin while controlled by Japan.
   2404 
   2405   Changes affecting past timestamps
   2406 
   2407     China's five zones have been simplified to two, since the post-1970
   2408     differences in the other three seem to have been imaginary.  The
   2409     zones Asia/Harbin, Asia/Chongqing, and Asia/Kashgar have been
   2410     removed; backwards-compatibility links still work, albeit with
   2411     different behaviors for timestamps before May 1980.  Asia/Urumqi's
   2412     1980 transition to UT +08 has been removed, so that it is now at
   2413     +06 and not +08.  (Thanks to Luther Ma and to Alois Treindl;
   2414     Treindl sent helpful translations of two papers by Guo Qingsheng.)
   2415 
   2416     Some zones have been turned into links, when they differed from existing
   2417     zones only for older UT offsets where data entries were likely invented.
   2418     These changes affect UT offsets in pre-1970 timestamps only.  This is
   2419     similar to the change in release 2013e, except this time for western
   2420     Africa.  The affected zones are: Africa/Bamako, Africa/Banjul,
   2421     Africa/Conakry, Africa/Dakar, Africa/Freetown, Africa/Lome,
   2422     Africa/Nouakchott, Africa/Ouagadougou, Africa/Sao_Tome, and
   2423     Atlantic/St_Helena.  This also affects the backwards-compatibility
   2424     link Africa/Timbuktu.  (Thanks to Alan Barrett, Stephen Colebourne,
   2425     Tim Parenti, and David Patte for reporting problems in earlier
   2426     versions of this change.)
   2427 
   2428     Asia/Shanghai's pre-standard-time UT offset has been changed from
   2429     8:05:57 to 8:05:43, the location of Xujiahui Observatory.  Its
   2430     transition to standard time has been changed from 1928 to 1901.
   2431 
   2432     Asia/Taipei switched to JWST on 1896-01-01, then to JST on 1937-10-01,
   2433     then to CST on 1945-09-21 at 01:00, and did not observe DST in 1945.
   2434     In 1946 it observed DST from 05-15 through 09-30; in 1947
   2435     from 04-15 through 10-31; and in 1979 from 07-01 through 09-30.
   2436     (Thanks to Yu-Cheng Chuang.)
   2437 
   2438     Asia/Riyadh's transition to standard time is now 1947-03-14, not 1950.
   2439 
   2440     Europe/Helsinki's 1942 fall-back transition was 10-04 at 01:00, not
   2441     10-03 at 00:00.  (Thanks to Konstantin Hyppnen.)
   2442 
   2443     Pacific/Pago_Pago has been changed from UT -11:30 to -11 for the
   2444     period from 1911 to 1950.
   2445 
   2446     Pacific/Chatham has been changed to New Zealand standard time plus
   2447     45 minutes for the period before 1957, reflecting a 1956 remark in
   2448     the New Zealand parliament.
   2449 
   2450     Europe/Budapest has several pre-1946 corrections: in 1918 the transition
   2451     out of DST was on 09-16, not 09-29; in 1919 it was on 11-24, not 09-15; in
   2452     1945 it was on 11-01, not 11-03; in 1941 the transition to DST was 04-08
   2453     not 04-06 at 02:00; and there was no DST in 1920.
   2454 
   2455     Africa/Accra is now assumed to have observed DST from 1920 through 1935.
   2456 
   2457     Time in Russia before 1927 or so has been corrected by a few seconds in
   2458     the following zones: Europe/Moscow, Asia/Irkutsk, Asia/Tbilisi,
   2459     Asia/Tashkent, Asia/Vladivostok, Asia/Yekaterinburg, Europe/Helsinki, and
   2460     Europe/Riga.  Also, Moscow's location has been changed to its Kilometer 0
   2461     point.  (Thanks to Vladimir Karpinsky for the Moscow changes.)
   2462 
   2463   Changes affecting data format
   2464 
   2465     A new file 'zone1970.tab' supersedes 'zone.tab' in the installed data.
   2466     The new file's extended format allows multiple country codes per zone.
   2467     The older file is still installed but is deprecated; its format is
   2468     not changing and it will still be distributed for a while, but new
   2469     applications should use the new file.
   2470 
   2471     The new file format simplifies maintenance of obscure locations.
   2472     To test this, it adds coverage for the Crozet Islands and the
   2473     Scattered Islands.  (Thanks to Tobias Conradi and Antoine Leca.)
   2474 
   2475     The file 'iso3166.tab' is planned to switch from ASCII to UTF-8.
   2476     It is still ASCII now, but commentary about the switch has been added.
   2477     The new file 'zone1970.tab' already uses UTF-8.
   2478 
   2479   Changes affecting code
   2480 
   2481     'localtime', 'mktime', etc. now use much less stack space if ALL_STATE
   2482     is defined.  (Thanks to Elliott Hughes for reporting the problem.)
   2483 
   2484     'zic' no longer mishandles input when ignoring case in locales that
   2485     are not compatible with English, e.g., unibyte Turkish locales when
   2486     compiled with HAVE_GETTEXT.
   2487 
   2488     Error diagnostics of 'zic' and 'yearistype' have been reworded so that
   2489     they no longer use ASCII '-' as if it were a dash.
   2490 
   2491     'zic' now rejects output file names that contain '.' or '..' components.
   2492     (Thanks to Tim Parenti for reporting the problem.)
   2493 
   2494     'zic -v' now warns about output file names that do not follow
   2495     POSIX rules, or that contain a digit or '.'.  (Thanks to Arthur
   2496     David Olson for starting the ball rolling on this.)
   2497 
   2498     Some lint has been removed when using GCC_DEBUG_FLAGS with GCC 4.9.0.
   2499 
   2500   Changes affecting build procedure
   2501 
   2502     'zic' no longer links in localtime.o and asctime.o, as they're not needed.
   2503     (Thanks to John Cochran.)
   2504 
   2505   Changes affecting documentation and commentary
   2506 
   2507     The 'Theory' file documents legacy names, the longstanding
   2508     exceptions to the POSIX-inspired file name rules.
   2509 
   2510     The 'zic' documentation clarifies the role of time types when
   2511     interpreting dates.  (Thanks to Arthur David Olson.)
   2512 
   2513     Documentation and commentary now prefer UTF-8 to US-ASCII,
   2514     allowing the use of proper accents in foreign words and names.
   2515     Code and data have not changed because of this.  (Thanks to
   2516     Garrett Wollman, Ian Abbott, and Guy Harris for helping to debug
   2517     this.)
   2518 
   2519     Non-HTML documentation and commentary now use plain-text URLs instead of
   2520     HTML insertions, and are more consistent about bracketing URLs when they
   2521     are not already surrounded by white space.  (Thanks to suggestions by
   2522     Steffen Nurpmeso.)
   2523 
   2524     There is new commentary about Xujiahui Observatory, the five time-zone
   2525     project in China from 1918 to 1949, timekeeping in Japanese-occupied
   2526     Shanghai, and Tibet Time in the 1950s.  The sharp-eyed can spot the
   2527     warlord Jin Shuren in the data.
   2528 
   2529     Commentary about the coverage of each Russian zone has been standardized.
   2530     (Thanks to Tim Parenti.)
   2531 
   2532     There is new commentary about contemporary timekeeping in Ethiopia.
   2533 
   2534     Obsolete comments about a 2007 proposal for DST in Kuwait has been removed.
   2535 
   2536     There is new commentary about time in Poland in 1919.
   2537 
   2538     Proper credit has been given to DST inventor George Vernon Hudson.
   2539 
   2540     Commentary about time in Metlakatla, AK and Resolute, NU has been
   2541     improved, with a new source for the former.
   2542 
   2543     In zone.tab, Pacific/Easter no longer mentions Salas y Gmez, as it
   2544     is uninhabited.
   2545 
   2546     Commentary about permanent Antarctic bases has been updated.
   2547 
   2548     Several typos have been corrected.  (Thanks to Tim Parenti for
   2549     contributing some of these fixes.)
   2550 
   2551     tz-link.htm now mentions the JavaScript libraries Moment Timezone,
   2552     TimezoneJS.Date, Walltime-js, and Timezone.  (Thanks to a heads-up
   2553     from Matt Johnson.)  Also, it mentions the Go 'latlong' package.
   2554     (Thanks to a heads-up from Dirkjan Ochtman.)
   2555 
   2556     The files usno1988, usno1989, usno1989a, usno1995, usno1997, and usno1998
   2557     have been removed.  These obsolescent US Naval Observatory entries were no
   2558     longer helpful for maintenance.  (Thanks to Tim Parenti for the suggestion.)
   2559 
   2560 
   2561 Release 2014e - 2014-06-12 21:53:52 -0700
   2562 
   2563   Changes affecting near-future timestamps
   2564 
   2565     Egypt's 2014 Ramadan-based transitions are June 26 and July 31 at 24:00.
   2566     (Thanks to Imed Chihi.)  Guess that from 2015 on Egypt will temporarily
   2567     switch to standard time at 24:00 the last Thursday before Ramadan, and
   2568     back to DST at 00:00 the first Friday after Ramadan.
   2569 
   2570     Similarly, Morocco's are June 28 at 03:00 and August 2 at 02:00.  (Thanks
   2571     to Milamber Space Network.)  Guess that from 2015 on Morocco will
   2572     temporarily switch to standard time at 03:00 the last Saturday before
   2573     Ramadan, and back to DST at 02:00 the first Saturday after Ramadan.
   2574 
   2575   Changes affecting past timestamps
   2576 
   2577     The abbreviation "MSM" (Moscow Midsummer Time) is now used instead of
   2578     "MSD" for Moscow's double daylight time in summer 1921.  Also, a typo
   2579     "VLASST" has been repaired to be "VLAST" for Vladivostok summer time
   2580     in 1991.  (Thanks to Hank W. for reporting the problems.)
   2581 
   2582   Changes affecting commentary
   2583 
   2584     tz-link.htm now cites RFC 7265 for jCal, mentions PTP and the
   2585     draft CalDAV extension, updates URLs for TSP, TZInfo, IATA, and
   2586     removes stale pointers to World Time Explorer and WORLDTIME.
   2587 
   2588 
   2589 Release 2014d - 2014-05-27 21:34:40 -0700
   2590 
   2591   Changes affecting code
   2592 
   2593     zic no longer generates files containing timestamps before the Big Bang.
   2594     This works around GNOME glib bug 878
   2595     <https://gitlab.gnome.org/GNOME/glib/issues/878>
   2596     (Thanks to Leonardo Chiquitto for reporting the bug, and to
   2597     Arthur David Olson and James Cloos for suggesting improvements to the fix.)
   2598 
   2599   Changes affecting documentation
   2600 
   2601     tz-link.htm now mentions GNOME.
   2602 
   2603 
   2604 Release 2014c - 2014-05-13 07:44:13 -0700
   2605 
   2606   Changes affecting near-future timestamps
   2607 
   2608     Egypt observes DST starting 2014-05-15 at 24:00.
   2609     (Thanks to Ahmad El-Dardiry and Gunther Vermier.)
   2610     Details have not been announced, except that DST will not be observed
   2611     during Ramadan.  Guess that DST will stop during the same Ramadan dates as
   2612     Morocco, and that Egypt's future spring and fall transitions will be the
   2613     same as 2010 when it last observed DST, namely April's last Friday at
   2614     00:00 to September's last Thursday at 23:00 standard time.  Also, guess
   2615     that Ramadan transitions will be at 00:00 standard time.
   2616 
   2617   Changes affecting code
   2618 
   2619     zic now generates transitions for minimum time values, eliminating guesswork
   2620     when handling low-valued timestamps.  (Thanks to Arthur David Olson.)
   2621 
   2622     Port to Cygwin sans glibc.  (Thanks to Arthur David Olson.)
   2623 
   2624   Changes affecting commentary and documentation
   2625 
   2626     Remove now-confusing comment about Jordan.  (Thanks to Oleksii Nochovnyi.)
   2627 
   2628 
   2629 Release 2014b - 2014-03-24 21:28:50 -0700
   2630 
   2631   Changes affecting near-future timestamps
   2632 
   2633     Crimea switches to Moscow time on 2014-03-30 at 02:00 local time.
   2634     (Thanks to Alexander Krivenyshev.)  Move its zone.tab entry from UA to RU.
   2635 
   2636     New entry for Troll station, Antarctica.  (Thanks to Paul-Inge Flakstad and
   2637     Bengt-Inge Larsson.)  This is currently an approximation; a better version
   2638     will require the zic and localtime fixes mentioned below, and the plan is
   2639     to wait for a while until at least the zic fixes propagate.
   2640 
   2641   Changes affecting code
   2642 
   2643     'zic' and 'localtime' no longer reject locations needing four transitions
   2644     per year for the foreseeable future.  (Thanks to Andrew Main (Zefram).)
   2645     Also, 'zic' avoids some unlikely failures due to integer overflow.
   2646 
   2647   Changes affecting build procedure
   2648 
   2649     'make check' now detects Rule lines defined but never used.
   2650     The NZAQ rules, an instance of this problem, have been removed.
   2651 
   2652   Changes affecting commentary and documentation
   2653 
   2654     Fix Tuesday/Thursday typo in description of time in Israel.
   2655     (Thanks to Bert Katz via Pavel Kharitonov and Mike Frysinger.)
   2656 
   2657     Microsoft Windows 8.1 doesn't support tz database names.  (Thanks
   2658     to Donald MacQueen.)  Instead, the Microsoft Windows Store app
   2659     library supports them.
   2660 
   2661     Add comments about Johnston Island time in the 1960s.
   2662     (Thanks to Lyle McElhaney.)
   2663 
   2664     Morocco's 2014 DST start will be as predicted.
   2665     (Thanks to Sebastien Willemijns.)
   2666 
   2667 
   2668 Release 2014a - 2014-03-07 23:30:29 -0800
   2669 
   2670   Changes affecting near-future timestamps
   2671 
   2672     Turkey begins DST on 2014-03-31, not 03-30.  (Thanks to Faruk Pasin for
   2673     the heads-up, and to Tim Parenti for simplifying the update.)
   2674 
   2675   Changes affecting past timestamps
   2676 
   2677     Fiji ended DST on 2014-01-19 at 02:00, not the previously-scheduled 03:00.
   2678     (Thanks to Steffen Thorsen.)
   2679 
   2680     Ukraine switched from Moscow to Eastern European time on 1990-07-01
   2681     (not 1992-01-01), and observed DST during the entire next winter.
   2682     (Thanks to Vladimir in Moscow via Alois Treindl.)
   2683 
   2684     In 1988 Israel observed DST from 04-10 to 09-04, not 04-09 to 09-03.
   2685     (Thanks to Avigdor Finkelstein.)
   2686 
   2687   Changes affecting code
   2688 
   2689     A uninitialized-storage bug in 'localtime' has been fixed.
   2690     (Thanks to Logan Chien.)
   2691 
   2692   Changes affecting the build procedure
   2693 
   2694     The settings for 'make check_web' now default to Ubuntu 13.10.
   2695 
   2696   Changes affecting commentary and documentation
   2697 
   2698     The boundary of the US Pacific time zone is given more accurately.
   2699     (Thanks to Alan Mintz.)
   2700 
   2701     Chile's 2014 DST will be as predicted.  (Thanks to Jos Miguel Garrido.)
   2702 
   2703     Paraguay's 2014 DST will be as predicted.  (Thanks to Carlos Ral Perasso.)
   2704 
   2705     Better descriptions of countries with same time zone history as
   2706     Trinidad and Tobago since 1970.  (Thanks to Alan Barrett for suggestion.)
   2707 
   2708     Several changes affect tz-link.htm, the main web page.
   2709 
   2710       Mention Time.is (thanks to Even Scharning) and WX-now (thanks to
   2711       David Braverman).
   2712 
   2713       Mention xCal (Internet RFC 6321) and jCal.
   2714 
   2715       Microsoft has some support for tz database names.
   2716 
   2717       CLDR data formats include both XML and JSON.
   2718 
   2719       Mention Maggiolo's map of solar vs standard time.
   2720       (Thanks to Arthur David Olson.)
   2721 
   2722       Mention TZ4Net.  (Thanks to Matt Johnson.)
   2723 
   2724       Mention the timezone-olson Haskell package.
   2725 
   2726       Mention zeitverschiebung.net.  (Thanks to Martin Jger.)
   2727 
   2728       Remove moribund links to daylight-savings-time.info and to
   2729       Simple Timer + Clocks.
   2730 
   2731       Update two links.  (Thanks to Oscar van Vlijmen.)
   2732 
   2733       Fix some formatting glitches, e.g., remove random newlines from
   2734       abbr elements' title attributes.
   2735 
   2736 
   2737 Release 2013i - 2013-12-17 07:25:23 -0800
   2738 
   2739   Changes affecting near-future timestamps:
   2740 
   2741     Jordan switches back to standard time at 00:00 on December 20, 2013.
   2742     The 2006-2011 transition schedule is planned to resume in 2014.
   2743     (Thanks to Steffen Thorsen.)
   2744 
   2745   Changes affecting past timestamps:
   2746 
   2747     In 2004, Cuba began DST on March 28, not April 4.
   2748     (Thanks to Steffen Thorsen.)
   2749 
   2750   Changes affecting code
   2751 
   2752     The compile-time flag NOSOLAR has been removed, as nowadays the
   2753     benefit of slightly shrinking runtime table size is outweighed by the
   2754     cost of disallowing potential future updates that exceed old limits.
   2755 
   2756   Changes affecting documentation and commentary
   2757 
   2758     The files solar87, solar88, and solar89 are no longer distributed.
   2759     They were a negative experiment - that is, a demonstration that
   2760     tz data can represent solar time only with some difficulty and error.
   2761     Their presence in the distribution caused confusion, as Riyadh
   2762     civil time was generally not solar time in those years.
   2763 
   2764     tz-link.htm now mentions Noda Time.  (Thanks to Matt Johnson.)
   2765 
   2766 
   2767 Release 2013h - 2013-10-25 15:32:32 -0700
   2768 
   2769   Changes affecting current and future timestamps:
   2770 
   2771     Libya has switched its UT offset back to +02 without DST, instead
   2772     of +01 with DST.  (Thanks to Even Scharning.)
   2773 
   2774     Western Sahara (Africa/El_Aaiun) uses Morocco's DST rules.
   2775     (Thanks to Gwillim Law.)
   2776 
   2777   Changes affecting future timestamps:
   2778 
   2779     Acre and (we guess) western Amazonas will switch from UT -04 to -05
   2780     on 2013-11-10.  This affects America/Rio_Branco and America/Eirunepe.
   2781     (Thanks to Steffen Thorsen.)
   2782 
   2783     Add entries for DST transitions in Morocco in the year 2038.
   2784     This avoids some year-2038 glitches introduced in 2013g.
   2785     (Thanks to Yoshito Umaoka for reporting the problem.)
   2786 
   2787   Changes affecting API
   2788 
   2789     The 'tzselect' command no longer requires the 'select' command,
   2790     and should now work with /bin/sh on more platforms.  It also works
   2791     around a bug in BusyBox awk before version 1.21.0.  (Thanks to
   2792     Patrick 'P. J.' McDermott and Alan Barrett.)
   2793 
   2794   Changes affecting code
   2795 
   2796     Fix localtime overflow bugs with 32-bit unsigned time_t.
   2797 
   2798     zdump no longer assumes sscanf returns maximal values on overflow.
   2799 
   2800   Changes affecting the build procedure
   2801 
   2802     The builder can specify which programs to use, if any, instead of
   2803     'ar' and 'ranlib', and libtz.a is now built locally before being
   2804     installed.  (Thanks to Michael Forney.)
   2805 
   2806     A dependency typo in the 'zdump' rule has been fixed.
   2807     (Thanks to Andrew Paprocki.)
   2808 
   2809     The Makefile has been simplified by assuming that 'mkdir -p' and 'cp -f'
   2810     work as specified by POSIX.2-1992 or later; this is portable nowadays.
   2811 
   2812     'make clean' no longer removes 'leapseconds', since it's
   2813     host-independent and is part of the distribution.
   2814 
   2815     The unused makefile macros TZCSRCS, TZDSRCS, DATESRCS have been removed.
   2816 
   2817   Changes affecting documentation and commentary
   2818 
   2819     tz-link.htm now mentions TC TIMEZONE's draft time zone service protocol
   2820     (thanks to Mike Douglass) and TimezoneJS.Date (thanks to Jim Fehrle).
   2821 
   2822     Update URLs in tz-link page.  Add URLs for Microsoft Windows, since
   2823     8.1 introduces tz support.  Remove URLs for Tru64 and UnixWare (no
   2824     longer maintained) and for old advisories.  SOFA now does C.
   2825 
   2826 Release 2013g - 2013-09-30 21:08:26 -0700
   2827 
   2828   Changes affecting current and near-future timestamps
   2829 
   2830     Morocco now observes DST from the last Sunday in March to the last
   2831     Sunday in October, not April to September respectively.  (Thanks
   2832     to Steffen Thorsen.)
   2833 
   2834   Changes affecting 'zic'
   2835 
   2836     'zic' now runs on platforms that lack both hard links and symlinks.
   2837     (Thanks to Theo Veenker for reporting the problem, for MinGW.)
   2838     Also, fix some bugs on platforms that lack hard links but have symlinks.
   2839 
   2840     'zic -v' again warns that Asia/Tehran has no POSIX environment variable
   2841     to predict the far future, fixing a bug introduced in 2013e.
   2842 
   2843   Changes affecting the build procedure
   2844 
   2845     The 'leapseconds' file is again put into the tzdata tarball.
   2846     Also, 'leapseconds.awk', so tzdata is self-contained.  (Thanks to
   2847     Matt Burgess and Ian Abbott.)  The timestamps of these and other
   2848     dependent files in tarballs are adjusted more consistently.
   2849 
   2850   Changes affecting documentation and commentary
   2851 
   2852     The README file is now part of the data tarball as well as the code.
   2853     It now states that files are public domain unless otherwise specified.
   2854     (Thanks to Andrew Main (Zefram) for asking for clarifications.)
   2855     Its details about the 1989 release moved to a place of honor near
   2856     the end of NEWS.
   2857 
   2858 
   2859 Release 2013f - 2013-09-24 23:37:36 -0700
   2860 
   2861   Changes affecting near-future timestamps
   2862 
   2863     Tocantins will very likely not observe DST starting this spring.
   2864     (Thanks to Steffen Thorsen.)
   2865 
   2866     Jordan will likely stay at UT +03 indefinitely, and will not fall
   2867     back this fall.
   2868 
   2869     Palestine will fall back at 00:00, not 01:00.  (Thanks to Steffen Thorsen.)
   2870 
   2871   Changes affecting API
   2872 
   2873     The types of the global variables 'timezone' and 'altzone' (if present)
   2874     have been changed back to 'long'.  This is required for 'timezone'
   2875     by POSIX, and for 'altzone' by common practice, e.g., Solaris 11.
   2876     These variables were originally 'long' in the tz code, but were
   2877     mistakenly changed to 'time_t' in 1987; nobody reported the
   2878     incompatibility until now.  The difference matters on x32, where
   2879     'long' is 32 bits and 'time_t' is 64.  (Thanks to Elliott Hughes.)
   2880 
   2881   Changes affecting the build procedure
   2882 
   2883     Avoid long strings in leapseconds.awk to work around a mawk bug.
   2884     (Thanks to Cyril Baurand.)
   2885 
   2886   Changes affecting documentation and commentary
   2887 
   2888     New file 'NEWS' that contains release notes like this one.
   2889 
   2890     Paraguay's law does not specify DST transition time; 00:00 is customary.
   2891     (Thanks to Waldemar Villamayor-Venialbo.)
   2892 
   2893     Minor capitalization fixes.
   2894 
   2895   Changes affecting version-control only
   2896 
   2897     The experimental GitHub repository now contains annotated and
   2898     signed tags for recent releases, e.g., '2013e' for Release 2013e.
   2899     Releases are tagged starting with 2012e; earlier releases were
   2900     done differently, and tags would either not have a simple name or
   2901     not exactly match what was released.
   2902 
   2903     'make set-timestamps' is now simpler and a bit more portable.
   2904 
   2905 
   2906 Release 2013e - 2013-09-19 23:50:04 -0700
   2907 
   2908   Changes affecting near-future timestamps
   2909 
   2910     This year Fiji will start DST on October 27, not October 20.
   2911     (Thanks to David Wheeler for the heads-up.)  For now, guess that
   2912     Fiji will continue to spring forward the Sunday before the fourth
   2913     Monday in October.
   2914 
   2915   Changes affecting current and future time zone abbreviations
   2916 
   2917     Use WIB/WITA/WIT rather than WIT/CIT/EIT for alphabetic Indonesian
   2918     time zone abbreviations since 1932.  (Thanks to George Ziegler,
   2919     Priyadi Iman Nurcahyo, Zakaria, Jason Grimes, Martin Pitt, and
   2920     Benny Lin.)  This affects Asia/Dili, Asia/Jakarta, Asia/Jayapura,
   2921     Asia/Makassar, and Asia/Pontianak.
   2922 
   2923     Use ART (UT -03, standard time), rather than WARST (also -03, but
   2924     daylight saving time) for San Luis, Argentina since 2009.
   2925 
   2926   Changes affecting Godthb timestamps after 2037 if version mismatch
   2927 
   2928     Allow POSIX-like TZ strings where the transition time's hour can
   2929     range from -167 through 167, instead of the POSIX-required 0
   2930     through 24.  E.g., TZ='FJT-12FJST,M10.3.1/146,M1.3.4/75' for the
   2931     new Fiji rules.  This is a more-compact way to represent
   2932     far-future timestamps for America/Godthab, America/Santiago,
   2933     Antarctica/Palmer, Asia/Gaza, Asia/Hebron, Asia/Jerusalem,
   2934     Pacific/Easter, and Pacific/Fiji.  Other zones are unaffected by
   2935     this change.  (Derived from a suggestion by Arthur David Olson.)
   2936 
   2937     Allow POSIX-like TZ strings where daylight saving time is in
   2938     effect all year.  E.g., TZ='WART4WARST,J1/0,J365/25' for Western
   2939     Argentina Summer Time all year.  This supports a more-compact way
   2940     to represent the 2013d data for America/Argentina/San_Luis.
   2941     Because of the change for San Luis noted above this change does not
   2942     affect the current data.  (Thanks to Andrew Main (Zefram) for
   2943     suggestions that improved this change.)
   2944 
   2945     Where these two TZ changes take effect, there is a minor extension
   2946     to the tz file format in that it allows new values for the
   2947     embedded TZ-format string, and the tz file format version number
   2948     has therefore been increased from 2 to 3 as a precaution.
   2949     Version-2-based client code should continue to work as before for
   2950     all timestamps before 2038.  Existing version-2-based client code
   2951     (tzcode, GNU/Linux, Solaris) has been tested on version-3-format
   2952     files, and typically works in practice even for timestamps after
   2953     2037; the only known exception is America/Godthab.
   2954 
   2955   Changes affecting timestamps before 1970
   2956 
   2957     Pacific/Johnston is now a link to Pacific/Honolulu.  This corrects
   2958     some errors before 1947.
   2959 
   2960     Some zones have been turned into links, when they differ from existing
   2961     zones only in older data entries that were likely invented or that
   2962     differ only in LMT or transitions from LMT.  These changes affect
   2963     only timestamps before 1943.  The affected zones are:
   2964     Africa/Juba, America/Anguilla, America/Aruba, America/Dominica,
   2965     America/Grenada, America/Guadeloupe, America/Marigot,
   2966     America/Montserrat, America/St_Barthelemy, America/St_Kitts,
   2967     America/St_Lucia, America/St_Thomas, America/St_Vincent,
   2968     America/Tortola, and Europe/Vaduz.  (Thanks to Alois Treindl for
   2969     confirming that the old Europe/Vaduz zone was wrong and the new
   2970     link is better for WWII-era times.)
   2971 
   2972     Change Kingston Mean Time from -5:07:12 to -5:07:11.  This affects
   2973     America/Cayman, America/Jamaica and America/Grand_Turk timestamps
   2974     from 1890 to 1912.
   2975 
   2976     Change the UT offset of Bern Mean Time from 0:29:44 to 0:29:46.
   2977     This affects Europe/Zurich timestamps from 1853 to 1894.  (Thanks
   2978     to Alois Treindl.)
   2979 
   2980     Change the date of the circa-1850 Zurich transition from 1849-09-12
   2981     to 1853-07-16, overriding Shanks with data from Messerli about
   2982     postal and telegraph time in Switzerland.
   2983 
   2984   Changes affecting time zone abbreviations before 1970
   2985 
   2986     For Asia/Jakarta, use BMT (not JMT) for mean time from 1923 to 1932,
   2987     as Jakarta was called Batavia back then.
   2988 
   2989   Changes affecting API
   2990 
   2991     The 'zic' command now outputs a dummy transition when far-future
   2992     data can't be summarized using a TZ string, and uses a 402-year
   2993     window rather than a 400-year window.  For the current data, this
   2994     affects only the Asia/Tehran file.  It does not affect any of the
   2995     timestamps that this file represents, so zdump outputs the same
   2996     information as before.  (Thanks to Andrew Main (Zefram).)
   2997 
   2998     The 'date' command has a new '-r' option, which lets you specify
   2999     the integer time to display, a la FreeBSD.
   3000 
   3001     The 'tzselect' command has two new options '-c' and '-n', which lets you
   3002     select a zone based on latitude and longitude.
   3003 
   3004     The 'zic' command's '-v' option now warns about constructs that
   3005     require the new version-3 binary file format.  (Thanks to Arthur
   3006     David Olson for the suggestion.)
   3007 
   3008     Support for floating-point time_t has been removed.
   3009     It was always dicey, and POSIX no longer requires it.
   3010     (Thanks to Eric Blake for suggesting to the POSIX committee to
   3011     remove it, and thanks to Alan Barrett, Clive D.W. Feather, Andy
   3012     Heninger, Arthur David Olson, and Alois Treindl, for reporting
   3013     bugs and elucidating some of the corners of the old floating-point
   3014     implementation.)
   3015 
   3016     The signatures of 'offtime', 'timeoff', and 'gtime' have been
   3017     changed back to the old practice of using 'long' to represent UT
   3018     offsets.  This had been inadvertently and mistakenly changed to
   3019     'int_fast32_t'.  (Thanks to Christos Zoulas.)
   3020 
   3021     The code avoids undefined behavior on integer overflow in some
   3022     more places, including gmtime, localtime, mktime and zdump.
   3023 
   3024   Changes affecting the zdump utility
   3025 
   3026     zdump now outputs "UT" when referring to Universal Time, not "UTC".
   3027     "UTC" does not make sense for timestamps that predate the introduction
   3028     of UTC, whereas "UT", a more-generic term, does.  (Thanks to Steve Allen
   3029     for clarifying UT vs UTC.)
   3030 
   3031   Data changes affecting behavior of tzselect and similar programs
   3032 
   3033     Country code BQ is now called the more-common name "Caribbean Netherlands"
   3034     rather than the more-official "Bonaire, St Eustatius & Saba".
   3035 
   3036     Remove from zone.tab the names America/Montreal, America/Shiprock,
   3037     and Antarctica/South_Pole, as they are equivalent to existing
   3038     same-country-code zones for post-1970 timestamps.  The data entries for
   3039     these names are unchanged, so the names continue to work as before.
   3040 
   3041   Changes affecting code internals
   3042 
   3043     zic -c now runs way faster on 64-bit hosts when given large numbers.
   3044 
   3045     zic now uses vfprintf to avoid allocating and freeing some memory.
   3046 
   3047     tzselect now computes the list of continents from the data,
   3048     rather than have it hard-coded.
   3049 
   3050     Minor changes pacify GCC 4.7.3 and GCC 4.8.1.
   3051 
   3052   Changes affecting the build procedure
   3053 
   3054     The 'leapseconds' file is now generated automatically from a
   3055     new file 'leap-seconds.list', which is a copy of
   3056     <ftp://ftp.nist.gov/pub/time/leap-seconds.list>
   3057     A new source file 'leapseconds.awk' implements this.
   3058     The goal is simplification of the future maintenance of 'leapseconds'.
   3059 
   3060     When building the 'posix' or 'right' subdirectories, if the
   3061     subdirectory would be a copy of the default subdirectory, it is
   3062     now made a symbolic link if that is supported.  This saves about
   3063     2 MB of file system space.
   3064 
   3065     The links America/Shiprock and Antarctica/South_Pole have been
   3066     moved to the 'backward' file.  This affects only nondefault builds
   3067     that omit 'backward'.
   3068 
   3069   Changes affecting version-control only
   3070 
   3071     .gitignore now ignores 'date'.
   3072 
   3073   Changes affecting documentation and commentary
   3074 
   3075     Changes to the 'tzfile' man page
   3076 
   3077       It now mentions that the binary file format may be extended in
   3078       future versions by appending data.
   3079 
   3080       It now refers to the 'zdump' and 'zic' man pages.
   3081 
   3082     Changes to the 'zic' man page
   3083 
   3084       It lists conditions that elicit a warning with '-v'.
   3085 
   3086       It says that the behavior is unspecified when duplicate names
   3087       are given, or if the source of one link is the target of another.
   3088 
   3089       Its examples are updated to match the latest data.
   3090 
   3091       The definition of white space has been clarified slightly.
   3092       (Thanks to Michael Deckers.)
   3093 
   3094     Changes to the 'Theory' file
   3095 
   3096       There is a new section about the accuracy of the tz database,
   3097       describing the many ways that errors can creep in, and
   3098       explaining why so many of the pre-1970 timestamps are wrong or
   3099       misleading (thanks to Steve Allen, Lester Caine, and Garrett
   3100       Wollman for discussions that contributed to this).
   3101 
   3102       The 'Theory' file describes LMT better (this follows a
   3103       suggestion by Guy Harris).
   3104 
   3105       It refers to the 2013 edition of POSIX rather than the 2004 edition.
   3106 
   3107       It's mentioned that excluding 'backward' should not affect the
   3108       other data, and it suggests at least one zone.tab name per
   3109       inhabited country (thanks to Stephen Colebourne).
   3110 
   3111       Some longstanding restrictions on names are documented, e.g.,
   3112       'America/New_York' precludes 'America/New_York/Bronx'.
   3113 
   3114       It gives more reasons for the 1970 cutoff.
   3115 
   3116       It now mentions which time_t variants are supported, such as
   3117       signed integer time_t.  (Thanks to Paul Goyette for reporting
   3118       typos in an experimental version of this change.)
   3119 
   3120       (Thanks to Philip Newton for correcting typos in these changes.)
   3121 
   3122     Documentation and commentary is more careful to distinguish UT in
   3123     general from UTC in particular.  (Thanks to Steve Allen.)
   3124 
   3125     Add a better source for the Zurich 1894 transition.
   3126     (Thanks to Pierre-Yves Berger.)
   3127 
   3128     Update shapefile citations in tz-link.htm.  (Thanks to Guy Harris.)
   3129 
   3130 
   3131 Release 2013d - 2013-07-05 07:38:01 -0700
   3132 
   3133   Changes affecting future timestamps:
   3134 
   3135     Morocco's midsummer transitions this year are July 7 and August 10,
   3136     not July 9 and August 8.  (Thanks to Andrew Paprocki.)
   3137 
   3138     Israel now falls back on the last Sunday of October.
   3139     (Thanks to Ephraim Silverberg.)
   3140 
   3141   Changes affecting past timestamps:
   3142 
   3143     Specify Jerusalem's location more precisely; this changes the pre-1880
   3144     times by 2 s.
   3145 
   3146   Changing affecting metadata only:
   3147 
   3148     Fix typos in the entries for country codes BQ and SX.
   3149 
   3150   Changes affecting code:
   3151 
   3152     Rework the code to fix a bug with handling Australia/Macquarie on
   3153     32-bit hosts (thanks to Arthur David Olson).
   3154 
   3155     Port to platforms like NetBSD, where time_t can be wider than long.
   3156 
   3157     Add support for testing time_t types other than the system's.
   3158     Run 'make check_time_t_alternatives' to try this out.
   3159     Currently, the tests fail for unsigned time_t;
   3160     this should get fixed at some point.
   3161 
   3162   Changes affecting documentation and commentary:
   3163 
   3164     Deemphasize the significance of national borders.
   3165 
   3166     Update the zdump man page.
   3167 
   3168     Remove obsolete NOID comment (thanks to Denis Excoffier).
   3169 
   3170     Update several URLs and comments in the web pages.
   3171 
   3172     Spelling fixes (thanks to Kevin Lyda and Jonathan Leffler).
   3173 
   3174     Update URL for CLDR Zone->Tzid table (thanks to Yoshito Umaoka).
   3175 
   3176 
   3177 Release 2013c - 2013-04-19 16:17:40 -0700
   3178 
   3179   Changes affecting current and future timestamps:
   3180 
   3181     Palestine observed DST starting March 29, 2013.  (Thanks to
   3182     Steffen Thorsen.)  From 2013 on, Gaza and Hebron both observe DST,
   3183     with the predicted rules being the last Thursday in March at 24:00
   3184     to the first Friday on or after September 21 at 01:00.
   3185 
   3186     Assume that the recent change to Paraguay's DST rules is permanent,
   3187     by moving the end of DST to the 4th Sunday in March every year.
   3188     (Thanks to Carlos Ral Perasso.)
   3189 
   3190   Changes affecting past timestamps:
   3191 
   3192     Fix some historical data for Palestine to agree with that of
   3193     timeanddate.com, as follows:
   3194 
   3195 	  The spring 2008 change in Gaza and Hebron was on 00:00 Mar 28, not
   3196 	  00:00 Apr 1.
   3197 
   3198 	  The fall 2009 change in Gaza and Hebron on Sep 4 was at 01:00, not
   3199 	  02:00.
   3200 
   3201 	  The spring 2010 change in Hebron was 00:00 Mar 26, not 00:01 Mar 27.
   3202 
   3203 	  The spring 2011 change in Gaza was 00:01 Apr 1, not 12:01 Apr 2.
   3204 
   3205 	  The spring 2011 change in Hebron on Apr 1 was at 00:01, not 12:01.
   3206 
   3207 	  The fall 2011 change in Hebron on Sep 30 was at 00:00, not 03:00.
   3208 
   3209     Fix times of habitation for Macquarie to agree with the Tasmania
   3210     Parks & Wildlife Service history, which indicates that permanent
   3211     habitation was 1899-1919 and 1948 on.
   3212 
   3213   Changing affecting metadata only:
   3214 
   3215     Macquarie Island is politically part of Australia, not Antarctica.
   3216     (Thanks to Tobias Conradi.)
   3217 
   3218     Sort Macquarie more-consistently with other parts of Australia.
   3219     (Thanks to Tim Parenti.)
   3220 
   3221 
   3222 Release 2013b - 2013-03-10 22:33:40 -0700
   3223 
   3224   Changes affecting current and future timestamps:
   3225 
   3226     Haiti uses US daylight-saving rules this year, and presumably future years.
   3227     This changes timestamps starting today.  (Thanks to Steffen Thorsen.)
   3228 
   3229     Paraguay will end DST on March 24 this year.
   3230     (Thanks to Steffen Thorsen.)  For now, assume it's just this year.
   3231 
   3232     Morocco does not observe DST during Ramadan;
   3233     try to predict Ramadan in Morocco as best we can.
   3234     (Thanks to Erik Homoet for the heads-up.)
   3235 
   3236   Changes affecting commentary:
   3237 
   3238     Update URLs in tz-link page.  Add URLs for webOS, BB10, iOS.
   3239     Update URL for Solaris.  Mention Internet RFC 6557.
   3240     Update Internet RFCs 2445->5545, 2822->5322.
   3241     Switch from FTP to HTTP for Internet RFCs.
   3242 
   3243 
   3244 Release 2013a - 2013-02-27 09:20:35 -0800
   3245 
   3246   Change affecting binary data format:
   3247 
   3248     The zone offset at the end of version-2-format zone files is now
   3249     allowed to be 24:00, as per POSIX.1-2008.  (Thanks to Arthur David Olson.)
   3250 
   3251   Changes affecting current and future timestamps:
   3252 
   3253     Chile's 2013 rules, and we guess rules for 2014 and later, will be
   3254     the same as 2012, namely Apr Sun>=23 03:00 UTC to Sep Sun>=2 04:00 UTC.
   3255     (Thanks to Steffen Thorsen and Robert Elz.)
   3256 
   3257     New Zones Asia/Khandyga, Asia/Ust-Nera, Europe/Busingen.
   3258     (Thanks to Tobias Conradi and Arthur David Olson.)
   3259 
   3260   Many changes affect historical timestamps before 1940.
   3261   These were deduced from: Milne J. Civil time. Geogr J. 1899
   3262   Feb;13(2):173-94 <https://www.jstor.org/stable/1774359>.
   3263 
   3264   Changes affecting the code:
   3265 
   3266     Fix zic bug that mishandled Egypt's 2010 changes (this also affected
   3267     the data).  (Thanks to Arthur David Olson.)
   3268 
   3269     Fix localtime bug when time_t is unsigned and data files were generated
   3270     by a signed time_t system.  (Thanks to Doug Bailey for reporting and
   3271     to Arthur David Olson for fixing.)
   3272 
   3273     Allow the email address for bug reports to be set by the packager.
   3274     The default is tz (a] iana.org, as before.  (Thanks to Joseph S. Myers.)
   3275 
   3276     Update HTML checking to be compatible with Ubuntu 12.10.
   3277 
   3278     Check that files are a safe subset of ASCII.  At some point we may
   3279     relax this requirement to a safe subset of UTF-8.  Without the
   3280     check, some non-UTF-8 encodings were leaking into the distribution.
   3281 
   3282   Commentary changes:
   3283 
   3284     Restore a comment about copyright notices that was inadvertently deleted.
   3285     (Thanks to Arthur David Olson.)
   3286 
   3287     Improve the commentary about which districts observe what times
   3288     in Russia.  (Thanks to Oscar van Vlijmen and Arthur David Olson.)
   3289 
   3290     Add web page links to tz.js.
   3291 
   3292     Add "Run by the Monkeys" to tz-art.  (Thanks to Arthur David Olson.)
   3293 
   3294 
   3295 Release 2012j - 2012-11-12 18:34:49 -0800
   3296 
   3297   Libya moved to CET this weekend, but with DST planned next year.
   3298   (Thanks to Even Scharning, Steffen Thorsen, and Tim Parenti.)
   3299 
   3300   Signatures now have the extension .asc, not .sign, as that's more
   3301   standard.  (Thanks to Phil Pennock.)
   3302 
   3303   The output of 'zdump --version', and of 'zic --version', now
   3304   uses a format that is more typical for --version.
   3305   (Thanks to Joseph S. Myers.)
   3306 
   3307   The output of 'tzselect --help', 'zdump --help', and 'zic --help'
   3308   now uses tz (a] iana.org rather than the old elsie address.
   3309 
   3310   zic -v now complains about abbreviations that are less than 3
   3311   or more than 6 characters, as per Posix.  Formerly, it checked
   3312   for abbreviations that were more than 3.
   3313 
   3314   'make public' no longer puts its temporary directory under /tmp,
   3315   and uses the just-built zic rather than the system zic.
   3316 
   3317   Various fixes to documentation and commentary.
   3318 
   3319 
   3320 Release 2012i - 2012-11-03 12:57:09 -0700
   3321 
   3322   Cuba switches from DST tomorrow at 01:00.  (Thanks to Steffen Thorsen.)
   3323 
   3324   Linker flags can now be specified via LDFLAGS.
   3325   AWK now defaults to 'awk', not 'nawk'.
   3326   The shell in tzselect now defaults to /bin/bash, but this can
   3327   be overridden by specifying KSHELL.
   3328   The main web page now mentions the unofficial GitHub repository.
   3329   (Thanks to Mike Frysinger.)
   3330 
   3331   Tarball signatures can now be built by running 'make signatures'.
   3332   There are also new makefile rules 'tarballs', 'check_public', and
   3333   separate makefile rules for each tarball and signature file.
   3334   A few makefile rules are now more portable to strict POSIX.
   3335 
   3336   The main web page now lists the canonical IANA URL.
   3337 
   3338 
   3339 Release 2012h - 2012-10-26 22:49:10 -0700
   3340 
   3341   Bahia no longer has DST.  (Thanks to Kelley Cook.)
   3342 
   3343   Tocantins has DST.  (Thanks to Rodrigo Severo.)
   3344 
   3345   Israel has new DST rules next year.  (Thanks to Ephraim Silverberg.)
   3346 
   3347   Jordan stays on DST this winter.  (Thanks to Steffen Thorsen.)
   3348 
   3349   Web page updates.
   3350 
   3351   More C modernization, except that at Arthur David Olson's suggestion
   3352   the instances of 'register' were kept.
   3353 
   3354 
   3355 Release 2012g - 2012-10-17 20:59:45 -0700
   3356 
   3357   Samoa fall 2012 and later.  (Thanks to Nicholas Pereira and Robert Elz.)
   3358 
   3359   Palestine fall 2012.  (Thanks to Steffen Thorsen.)
   3360 
   3361   Assume C89.
   3362 
   3363   To attack the version-number problem, this release ships the file
   3364   'Makefile' (which contains the release number) in both the tzcode and
   3365   the tzdata tarballs.  The two Makefiles are identical, and should be
   3366   identical in any matching pair of tarballs, so it shouldn't matter
   3367   which order you extract the tarballs.  Perhaps we can come up with a
   3368   better version-number scheme at some point; this scheme does have the
   3369   virtue of not adding more files.
   3370 
   3371 
   3372 Release 2012f - 2012-09-12 23:17:03 -0700
   3373 
   3374   * australasia (Pacific/Fiji): Fiji DST is October 21 through January
   3375     20 this year.  (Thanks to Steffen Thorsen.)
   3376 
   3377 
   3378 Release 2012e - 2012-08-02 20:44:55 -0700
   3379 
   3380   * australasia (Pacific/Fakaofo): Tokelau is UT +13, not +14.
   3381     (Thanks to Steffen Thorsen.)
   3382 
   3383   * Use a single version number for both code and data.
   3384 
   3385   * .gitignore: New file.
   3386 
   3387   * Remove trailing white space.
   3388 
   3389 
   3390 Release code2012c-data2012d - 2012-07-19 16:35:33 -0700
   3391 
   3392   Changes for Morocco's timestamps, which take effect in a couple of
   3393   hours, along with infrastructure changes to accommodate how the tz
   3394   code and data are released on IANA.
   3395 
   3396 
   3397 Release data2012c - 2012-03-27 12:17:25 -0400
   3398 
   3399   africa
   3400 	Summer time changes for Morocco (to start late April 2012)
   3401 
   3402   asia
   3403 	Changes for 2012 for Gaza & the West Bank (Hebron) and Syria
   3404 
   3405   northamerica
   3406 	Haiti following US/Canada rules for 2012 (and we're assuming,
   3407 	for now anyway, for the future).
   3408 
   3409 
   3410 Release 2012b - 2012-03-02 12:29:15 +0700
   3411 
   3412   There is just one change to tzcode2012b (compared with 2012a):
   3413   the Makefile that was accidentally included with 2012a has been
   3414   replaced with the version that should have been there, which is
   3415   identical with the previous version (from tzcode2011i).
   3416 
   3417   There are just two changes in tzdata2012b compared with 2012a.
   3418 
   3419   Most significantly, summer time in Cuba has been delayed 3 weeks
   3420   (now starts April 1 rather than March 11).   Since Mar 11 (the old start
   3421   date, as listed in 2012a) is just a little over a week away, this
   3422   change is urgent.
   3423 
   3424   Less importantly, an excess tab in one of the changes in zone.tab
   3425   in 2012a has been removed.
   3426 
   3427 
   3428 Release 2012a - 2012-03-01 18:28:10 +0700
   3429 
   3430   The changes in tzcode2012a (compared to the previous version, 2011i)
   3431   are entirely to the README and tz-art.htm and tz-link.htm files, if
   3432   none of those concern you, you can ignore the code update.  The changes
   3433   reflect the changed addresses for the mailing list and the code and
   3434   data distribution points & methods (and a link to DateTime::TimeZone::Tzfile
   3435   has been added to tz-link.htm).
   3436 
   3437   In tzdata2012a (compared to the previous release, which was 2011n)
   3438   the major changes are:
   3439 	Chile 2011/2012 and 2012/2013 summer time date adjustments.
   3440 	Falkland Islands onto permanent summer time (we're assuming for the
   3441 		foreseeable future, though 2012 is all we're fairly certain of.)
   3442 	Armenia has abolished Summer Time.
   3443 	Tokelau jumped the International Date Line back last December
   3444 		(just the same as their near neighbour, Samoa).
   3445 	America/Creston is a new zone for a small area of British Columbia
   3446 	There will be a leapsecond 2012-06-30 23:59:60 UTC.
   3447 
   3448   Other minor changes are:
   3449 	Corrections to 1918 Canadian summer time end dates.
   3450 	Updated URL for UK time zone history (in comments)
   3451 	A few typos in Le Corre's list of free French place names (comments)
   3452 
   3453 
   3454 Release data2011n - 2011-10-30 14:57:54 +0700
   3455 
   3456   There are three changes of note - most urgently, Cuba (America/Havana)
   3457   has extended summer time by two weeks, now to end on Nov 13, rather than
   3458   the (already past) Oct 30.   Second, the Pridnestrovian Moldavian Republic
   3459   (Europe/Tiraspol) decided not to split from the rest of Moldova after
   3460   all, and consequently that zone has been removed (again) and reinstated
   3461   in the "backward" file as a link to Europe/Chisinau.   And third, the
   3462   end date for Fiji's summer time this summer was moved forward from the
   3463   earlier planned Feb 26, to Jan 22.
   3464 
   3465   Apart from that, Moldova (MD) returns to a single entry in zone.tab
   3466   (and the incorrect syntax that was in the 2011m version of that file
   3467   is so fixed - it would have been fixed in a different way had this
   3468   change not happened - that's the "missing" sccs version id).
   3469 
   3470 
   3471 Release data2011m - 2011-10-24 21:42:16 +0700
   3472 
   3473   In particular, the typos in comments in the data (2011-11-17 should have
   3474   been 2011-10-17 as Alan Barrett noted, and spelling of Tiraspol that
   3475   Tim Parenti noted) have been fixed, and the change for Ukraine has been
   3476   made in all 4 Ukrainian zones, rather than just Kiev (again, thanks to
   3477   Tim Parenti, and also Denys Gavrysh)
   3478 
   3479   In addition, I added Europe/Tiraspol to zone.tab.
   3480 
   3481   This time, all the files have new version numbers...  (including the files
   3482   otherwise unchanged in 2011m that were changed in 2011l but didn't get new
   3483   version numbers there...)
   3484 
   3485 
   3486 Release data2011l - 2011-10-10 11:15:43 +0700
   3487 
   3488   There are just 2 changes that cause different generated tzdata files from
   3489   zic, to Asia/Hebron and Pacific/Fiji - the possible change for Bahia, Brazil
   3490   is included, but commented out.  Compared with the diff I sent out last week,
   3491   this version also includes attributions for the sources for the changes
   3492   (in much the same format as ado used, but the html tags have not been
   3493   checked, verified, or used in any way at all, so if there are errors there,
   3494   please let me know.)
   3495 
   3496 
   3497 Release data2011k - 2011-09-20 17:54:03 -0400
   3498 
   3499   [not summarized]
   3500 
   3501 
   3502 Release data2011j - 2011-09-12 09:22:49 -0400
   3503 
   3504   (contemporary changes for Samoa; past changes for Kenya, Uganda, and
   3505   Tanzania); there are also two spelling corrections to comments in
   3506   the australasia file (with thanks to Christos Zoulas).
   3507 
   3508 
   3509 Release 2011i - 2011-08-29 05:56:32 -0400
   3510 
   3511   [not summarized]
   3512 
   3513 
   3514 Release data2011h - 2011-06-15 18:41:48 -0400
   3515 
   3516   Russia and Curaao changes
   3517 
   3518 
   3519 Release 2011g - 2011-04-25 09:07:22 -0400
   3520 
   3521   update the rules for Egypt to reflect its abandonment of DST this year
   3522 
   3523 
   3524 Release 2011f - 2011-04-06 17:14:53 -0400
   3525 
   3526   [not summarized]
   3527 
   3528 
   3529 Release 2011e - 2011-03-31 16:04:38 -0400
   3530 
   3531   Morocco, Chile, and tz-link changes
   3532 
   3533 
   3534 Release 2011d - 2011-03-14 09:18:01 -0400
   3535 
   3536   changes that impact present-day timestamps in Cuba, Samoa, and Turkey
   3537 
   3538 
   3539 Release 2011c - 2011-03-07 09:30:09 -0500
   3540 
   3541   These do affect current timestamps in Chile and Annette Island, Canada.
   3542 
   3543 
   3544 Release 2011b - 2011-02-07 08:44:50 -0500
   3545 
   3546   [not summarized]
   3547 
   3548 
   3549 Release 2011a - 2011-01-24 10:30:16 -0500
   3550 
   3551   [not summarized]
   3552 
   3553 
   3554 Release data2010o - 2010-11-01 09:18:23 -0400
   3555 
   3556   change to the end of DST in Fiji in 2011
   3557 
   3558 
   3559 Release 2010n - 2010-10-25 08:19:17 -0400
   3560 
   3561   [not summarized]
   3562 
   3563 
   3564 Release 2010m - 2010-09-27 09:24:48 -0400
   3565 
   3566   Hong Kong, Vostok, and zic.c changes
   3567 
   3568 
   3569 Release 2010l - 2010-08-16 06:57:25 -0400
   3570 
   3571   [not summarized]
   3572 
   3573 
   3574 Release 2010k - 2010-07-26 10:42:27 -0400
   3575 
   3576   [not summarized]
   3577 
   3578 
   3579 Release 2010j - 2010-05-10 09:07:48 -0400
   3580 
   3581   changes for Baha de Banderas and for version naming
   3582 
   3583 
   3584 Release data2010i - 2010-04-16 18:50:45 -0400
   3585 
   3586   the end of DST in Morocco on 2010-08-08
   3587 
   3588 
   3589 Release data2010h - 2010-04-05 09:58:56 -0400
   3590 
   3591   [not summarized]
   3592 
   3593 
   3594 Release data2010g - 2010-03-24 11:14:53 -0400
   3595 
   3596   [not summarized]
   3597 
   3598 
   3599 Release 2010f - 2010-03-22 09:45:46 -0400
   3600 
   3601   [not summarized]
   3602 
   3603 
   3604 Release data2010e - 2010-03-08 14:24:27 -0500
   3605 
   3606   corrects the Dhaka bug found by Danvin Ruangchan
   3607 
   3608 
   3609 Release data2010d - 2010-03-06 07:26:01 -0500
   3610 
   3611   [not summarized]
   3612 
   3613 
   3614 Release 2010c - 2010-03-01 09:20:58 -0500
   3615 
   3616   changes including KRE's suggestion for earlier initialization of
   3617   "goahead" and "goback" structure elements
   3618 
   3619 
   3620 Release code2010a - 2010-02-16 10:40:04 -0500
   3621 
   3622   [not summarized]
   3623 
   3624 
   3625 Release data2010b - 2010-01-20 12:37:01 -0500
   3626 
   3627   Mexico changes
   3628 
   3629 
   3630 Release data2010a - 2010-01-18 08:30:04 -0500
   3631 
   3632   changes to Dhaka
   3633 
   3634 
   3635 Release data2009u - 2009-12-26 08:32:28 -0500
   3636 
   3637   changes to DST in Bangladesh
   3638 
   3639 
   3640 Release 2009t - 2009-12-21 13:24:27 -0500
   3641 
   3642   [not summarized]
   3643 
   3644 
   3645 Release data2009s - 2009-11-14 10:26:32 -0500
   3646 
   3647   (cosmetic) Antarctica change and the DST-in-Fiji-in-2009-and-2010 change
   3648 
   3649 
   3650 Release 2009r - 2009-11-09 10:10:31 -0500
   3651 
   3652   "antarctica" and "tz-link.htm" changes
   3653 
   3654 
   3655 Release 2009q - 2009-11-02 09:12:40 -0500
   3656 
   3657   with two corrections as reported by Eric Muller and Philip Newton
   3658 
   3659 
   3660 Release data2009p - 2009-10-23 15:05:27 -0400
   3661 
   3662   Argentina (including San Luis) changes (with the correction from
   3663   Mariano Absatz)
   3664 
   3665 
   3666 Release data2009o - 2009-10-14 16:49:38 -0400
   3667 
   3668   Samoa (commentary only), Pakistan, and Bangladesh changes
   3669 
   3670 
   3671 Release data2009n - 2009-09-22 15:13:38 -0400
   3672 
   3673   added commentary for Argentina and a change to the end of DST in
   3674   2009 in Pakistan
   3675 
   3676 
   3677 Release data2009m - 2009-09-03 10:23:43 -0400
   3678 
   3679   Samoa and Palestine changes
   3680 
   3681 
   3682 Release data2009l - 2009-08-14 09:13:07 -0400
   3683 
   3684   Samoa (comments only) and Egypt
   3685 
   3686 
   3687 Release 2009k - 2009-07-20 09:46:08 -0400
   3688 
   3689   [not summarized]
   3690 
   3691 
   3692 Release data2009j - 2009-06-15 06:43:59 -0400
   3693 
   3694   Bangladesh change (with a short turnaround since the DST change is
   3695   impending)
   3696 
   3697 
   3698 Release 2009i - 2009-06-08 09:21:22 -0400
   3699 
   3700   updating for DST in Bangladesh this year
   3701 
   3702 
   3703 Release 2009h - 2009-05-26 09:19:14 -0400
   3704 
   3705   [not summarized]
   3706 
   3707 
   3708 Release data2009g - 2009-04-20 16:34:07 -0400
   3709 
   3710   Cairo
   3711 
   3712 
   3713 Release data2009f - 2009-04-10 11:00:52 -0400
   3714 
   3715   correct DST in Pakistan
   3716 
   3717 
   3718 Release 2009e - 2009-04-06 09:08:11 -0400
   3719 
   3720   [not summarized]
   3721 
   3722 
   3723 Release 2009d - 2009-03-23 09:38:12 -0400
   3724 
   3725   Morocco, Tunisia, Argentina, and American Astronomical Society changes
   3726 
   3727 
   3728 Release data2009c - 2009-03-16 09:47:51 -0400
   3729 
   3730   change to the start of Cuban DST
   3731 
   3732 
   3733 Release 2009b - 2009-02-09 11:15:22 -0500
   3734 
   3735   [not summarized]
   3736 
   3737 
   3738 Release 2009a - 2009-01-21 10:09:39 -0500
   3739 
   3740   [not summarized]
   3741 
   3742 
   3743 Release data2008i - 2008-10-21 12:10:25 -0400
   3744 
   3745   southamerica and zone.tab files, with Argentina DST rule changes and
   3746   United States zone reordering and recommenting
   3747 
   3748 
   3749 Release 2008h - 2008-10-13 07:33:56 -0400
   3750 
   3751   [not summarized]
   3752 
   3753 
   3754 Release 2008g - 2008-10-06 09:03:18 -0400
   3755 
   3756   Fix a broken HTML anchor and update Brazil's DST transitions;
   3757   there's also a slight reordering of information in tz-art.htm.
   3758 
   3759 
   3760 Release data2008f - 2008-09-09 22:33:26 -0400
   3761 
   3762   [not summarized]
   3763 
   3764 
   3765 Release 2008e - 2008-07-28 14:11:17 -0400
   3766 
   3767   changes by Arthur David Olson and Jesper Nrgaard Welen
   3768 
   3769 
   3770 Release data2008d - 2008-07-07 09:51:38 -0400
   3771 
   3772   changes by Arthur David Olson, Paul Eggert, and Rodrigo Severo
   3773 
   3774 
   3775 Release data2008c - 2008-05-19 17:48:03 -0400
   3776 
   3777   Pakistan, Morocco, and Mongolia
   3778 
   3779 
   3780 Release data2008b - 2008-03-24 08:30:59 -0400
   3781 
   3782   including renaming Asia/Calcutta to Asia/Kolkata, with a backward
   3783   link provided
   3784 
   3785 
   3786 Release 2008a - 2008-03-08 05:42:16 -0500
   3787 
   3788   [not summarized]
   3789 
   3790 
   3791 Release 2007k - 2007-12-31 10:25:22 -0500
   3792 
   3793   most importantly, changes to the "southamerica" file based on
   3794   Argentina's readoption of daylight saving time
   3795 
   3796 
   3797 Release 2007j - 2007-12-03 09:51:01 -0500
   3798 
   3799   1. eliminate the "P" (parameter) macro;
   3800 
   3801   2. the "noncontroversial" changes circulated on the time zone
   3802   mailing list (less the changes to "logwtmp.c");
   3803 
   3804   3. eliminate "too many transition" errors when "min" is used in time
   3805   zone rules;
   3806 
   3807   4. changes by Paul Eggert (including updated information for Venezuela).
   3808 
   3809 
   3810 Release data2007i - 2007-10-30 10:28:11 -0400
   3811 
   3812   changes for Cuba and Syria
   3813 
   3814 
   3815 Release 2007h - 2007-10-01 10:05:51 -0400
   3816 
   3817   changes by Paul Eggert, as well as an updated link to the ICU
   3818   project in tz-link.htm
   3819 
   3820 
   3821 Release 2007g - 2007-08-20 10:47:59 -0400
   3822 
   3823   changes by Paul Eggert
   3824 
   3825   The "leapseconds" file has been updated to incorporate the most
   3826   recent International Earth Rotation and Reference Systems Service
   3827   (IERS) bulletin.
   3828 
   3829   There's an addition to tz-art.htm regarding the television show "Medium".
   3830 
   3831 
   3832 Release 2007f - 2007-05-07 10:46:46 -0400
   3833 
   3834   changes by Paul Eggert (including Haiti, Turks and Caicos, and New
   3835   Zealand)
   3836 
   3837   changes to zic.c to allow hour values greater than 24 (along with
   3838   Paul's improved time value overflow checking)
   3839 
   3840 
   3841 Release 2007e - 2007-04-02 10:11:52 -0400
   3842 
   3843   Syria and Honduras changes by Paul Eggert
   3844 
   3845   zic.c variable renaming changes by Arthur David Olson
   3846 
   3847 
   3848 Release 2007d - 2007-03-20 08:48:30 -0400
   3849 
   3850   changes by Paul Eggert
   3851 
   3852   the elimination of white space at the ends of lines
   3853 
   3854 
   3855 Release 2007c - 2007-02-26 09:09:37 -0500
   3856 
   3857   changes by Paul Eggert
   3858 
   3859 
   3860 Release 2007b - 2007-02-12 09:34:20 -0500
   3861 
   3862   Paul Eggert's proposed change to the quotation handling logic in zic.c.
   3863 
   3864   changes to the commentary in "leapseconds" reflecting the IERS
   3865   announcement that there is to be no positive leap second at the end
   3866   of June 2007.
   3867 
   3868 
   3869 Release 2007a - 2007-01-08 12:28:29 -0500
   3870 
   3871   changes by Paul Eggert
   3872 
   3873   Derick Rethan's Asmara change
   3874 
   3875   Oscar van Vlijmen's Easter Island local mean time change
   3876 
   3877   symbolic link changes
   3878 
   3879 
   3880 Release 2006p - 2006-11-27 08:54:27 -0500
   3881 
   3882   changes by Paul Eggert
   3883 
   3884 
   3885 Release 2006o - 2006-11-06 09:18:07 -0500
   3886 
   3887   changes by Paul Eggert
   3888 
   3889 
   3890 Release 2006n - 2006-10-10 11:32:06 -0400
   3891 
   3892   changes by Paul Eggert
   3893 
   3894 
   3895 Release 2006m - 2006-10-02 15:32:35 -0400
   3896 
   3897   changes for Uruguay, Palestine, and Egypt by Paul Eggert
   3898 
   3899   (minimalist) changes to zic.8 to clarify "until" information
   3900 
   3901 
   3902 Release data2006l - 2006-09-18 12:58:11 -0400
   3903 
   3904   Paul's best-effort work on this coming weekend's Egypt time change
   3905 
   3906 
   3907 Release 2006k - 2006-08-28 12:19:09 -0400
   3908 
   3909   changes by Paul Eggert
   3910 
   3911 
   3912 Release 2006j - 2006-08-21 09:56:32 -0400
   3913 
   3914   changes by Paul Eggert
   3915 
   3916 
   3917 Release code2006i - 2006-08-07 12:30:55 -0400
   3918 
   3919   localtime.c fixes
   3920 
   3921   Ken Pizzini's conversion script
   3922 
   3923 
   3924 Release code2006h - 2006-07-24 09:19:37 -0400
   3925 
   3926   adds public domain notices to four files
   3927 
   3928   includes a fix for transition times being off by a second
   3929 
   3930   adds a new recording to the "arts" file (information courtesy Colin Bowern)
   3931 
   3932 
   3933 Release 2006g - 2006-05-08 17:18:09 -0400
   3934 
   3935   northamerica changes by Paul Eggert
   3936 
   3937 
   3938 Release 2006f - 2006-05-01 11:46:00 -0400
   3939 
   3940   a missing version number problem is fixed (with thanks to Bradley
   3941   White for catching the problem)
   3942 
   3943 
   3944 Release 2006d - 2006-04-17 14:33:43 -0400
   3945 
   3946   changes by Paul Eggert
   3947 
   3948   added new items to tz-arts.htm that were found by Paul
   3949 
   3950 
   3951 Release 2006c - 2006-04-03 10:09:32 -0400
   3952 
   3953   two sets of data changes by Paul Eggert
   3954 
   3955   a fencepost error fix in zic.c
   3956 
   3957   changes to zic.c and the "europe" file to minimize differences
   3958   between output produced by the old 32-bit zic and the new 64-bit
   3959   version
   3960 
   3961 
   3962 Release 2006b - 2006-02-20 10:08:18 -0500
   3963   [tz32code2006b + tz64code2006b + tzdata2006b]
   3964 
   3965   64-bit code
   3966 
   3967   All SCCS IDs were bumped to "8.1" for this release.
   3968 
   3969 
   3970 Release 2006a - 2006-01-30 08:59:31 -0500
   3971 
   3972   changes by Paul Eggert (in particular, Indiana time zone moves)
   3973 
   3974   an addition to the zic manual page to describe how special-case
   3975   transitions are handled
   3976 
   3977 
   3978 Release 2005r - 2005-12-27 09:27:13 -0500
   3979 
   3980   Canadian changes by Paul Eggert
   3981 
   3982   They also add "<pre>" directives to time zone data files and reflect
   3983   changes to warning message logic in "zdump.c" (but with calls to
   3984   "gettext" kept unbundled at the suggestion of Ken Pizzini).
   3985 
   3986 
   3987 Release 2005q - 2005-12-13 09:17:09 -0500
   3988 
   3989   Nothing earth-shaking here:
   3990 	1.  Electronic mail addresses have been removed.
   3991 	2.  Casts of the return value of exit have been removed.
   3992 	3.  Casts of the argument of is.* macros have been added.
   3993 	4.  Indentation in one section of zic.c has been fixed.
   3994 	5.  References to dead URLs in the data files have been dealt with.
   3995 
   3996 
   3997 Release 2005p - 2005-12-05 10:30:53 -0500
   3998 
   3999   "systemv", "tz-link.htm", and "zdump.c" changes
   4000   (less the casts of arguments to the is* macros)
   4001 
   4002 
   4003 Release 2005o - 2005-11-28 10:55:26 -0500
   4004 
   4005   Georgia, Cuba, Nicaragua, and Jordan changes by Paul Eggert
   4006 
   4007   zdump.c lint fixes by Arthur David Olson
   4008 
   4009 
   4010 Release 2005n - 2005-10-03 09:44:09 -0400
   4011 
   4012   changes by Paul Eggert (both the Uruguay changes and the Kyrgyzstan
   4013   et al. changes)
   4014 
   4015 
   4016 Release 2005m - 2005-08-29 12:15:40 -0400
   4017 
   4018   changes by Paul Eggert (with a small tweak to the tz-art change)
   4019 
   4020   a declaration of an unused variable has been removed from zdump.c
   4021 
   4022 
   4023 Release 2005l - 2005-08-22 12:06:39 -0400
   4024 
   4025   changes by Paul Eggert
   4026 
   4027   overflow/underflow checks by Arthur David Olson, minus changes to
   4028   the "Theory" file about the pending addition of 64-bit data (I grow
   4029   less confident of the changes being accepted with each passing day,
   4030   and the changes no longer increase the data files nine-fold--there's
   4031   less than a doubling in size by my local Sun's reckoning)
   4032 
   4033 
   4034 Release 2005k - 2005-07-14 14:14:24 -0400
   4035 
   4036   The "leapseconds" file has been edited to reflect the recently
   4037   announced leap second at the end of 2005.
   4038 
   4039   I've also deleted electronic mail addresses from the files as an
   4040   anti-spam measure.
   4041 
   4042 
   4043 Release 2005j - 2005-06-13 14:34:13 -0400
   4044 
   4045   These reflect changes to limit the length of time zone abbreviations
   4046   and the characters used in those abbreviations.
   4047 
   4048   There are also changes to handle POSIX-style "quoted" timezone
   4049   environment variables.
   4050 
   4051   The changes were circulated on the time zone mailing list; the only
   4052   change since then was the removal of a couple of minimum-length of
   4053   abbreviation checks.
   4054 
   4055 
   4056 Release data2005i - 2005-04-21 15:04:16 -0400
   4057 
   4058   changes (most importantly to Nicaragua and Haiti) by Paul Eggert
   4059 
   4060 
   4061 Release 2005h - 2005-04-04 11:24:47 -0400
   4062 
   4063   changes by Paul Eggert
   4064 
   4065   minor changes to Makefile and zdump.c to produce more useful output
   4066   when doing a "make typecheck"
   4067 
   4068 
   4069 Release 2005g - 2005-03-14 10:11:21 -0500
   4070 
   4071   changes by Paul Eggert (a change to current DST rules in Uruguay and
   4072   an update to a link to time zone software)
   4073 
   4074 
   4075 Release 2005f - 2005-03-01 08:45:32 -0500
   4076 
   4077   data and documentation changes by Paul Eggert
   4078 
   4079 
   4080 Release 2005e - 2005-02-10 15:59:44 -0500
   4081 
   4082   [not summarized]
   4083 
   4084 
   4085 Release code2005d - 2005-01-31 09:21:47 -0500
   4086 
   4087   make zic complain about links to links if the -v flag is used
   4088 
   4089   have "make public" do more code checking
   4090 
   4091   add an include to "localtime.c" for the benefit of gcc systems
   4092 
   4093 
   4094 Release 2005c - 2005-01-17 18:36:29 -0500
   4095 
   4096   get better results when mktime runs on a system where time_t is double
   4097 
   4098   changes to the data files (most importantly to Paraguay)
   4099 
   4100 
   4101 Release 2005b - 2005-01-10 09:19:54 -0500
   4102 
   4103   Get localtime and gmtime working on systems with exotic time_t types.
   4104 
   4105   Update the leap second commentary in the "leapseconds" file.
   4106 
   4107 
   4108 Release 2005a - 2005-01-01 13:13:44 -0500
   4109 
   4110   [not summarized]
   4111 
   4112 
   4113 Release code2004i - 2004-12-14 13:42:58 -0500
   4114 
   4115   Deal with systems where time_t is unsigned.
   4116 
   4117 
   4118 Release code2004h - 2004-12-07 11:40:18 -0500
   4119 
   4120   64-bit-time_t changes
   4121 
   4122 
   4123 Release 2004g - 2004-11-02 09:06:01 -0500
   4124 
   4125   update to Cuba (taking effect this weekend)
   4126 
   4127   other changes by Paul Eggert
   4128 
   4129   correction of the spelling of Oslo
   4130 
   4131   changed versions of difftime.c and private.h
   4132 
   4133 
   4134 Release code2004f - 2004-10-21 10:25:22 -0400
   4135 
   4136   Cope with wide-ranging tm_year values.
   4137 
   4138 
   4139 Release 2004e - 2004-10-11 14:47:21 -0400
   4140 
   4141   Brazil/Argentina/Israel changes by Paul Eggert
   4142 
   4143   changes to tz-link.htm by Paul
   4144 
   4145   one small fix to Makefile
   4146 
   4147 
   4148 Release 2004d - 2004-09-22 08:27:29 -0400
   4149 
   4150   Avoid overflow problems when TM_YEAR_BASE is added to an integer.
   4151 
   4152 
   4153 Release 2004c - 2004-08-11 12:06:26 -0400
   4154 
   4155   asctime-related changes
   4156 
   4157   (variants of) some of the documentation changes suggested by Paul Eggert
   4158 
   4159 
   4160 Release 2004b - 2004-07-19 14:33:35 -0400
   4161 
   4162   data changes by Paul Eggert - most importantly, updates for Argentina
   4163 
   4164 
   4165 Release 2004a - 2004-05-27 12:00:47 -0400
   4166 
   4167   changes by Paul Eggert
   4168 
   4169   Handle DST transitions that occur at the end of a month in some
   4170   years but at the start of the following month in other years.
   4171 
   4172   Add a copy of the correspondence that's the basis for claims about
   4173   DST in the Navajo Nation.
   4174 
   4175 
   4176 Release 2003e - 2003-12-15 09:36:47 -0500
   4177 
   4178   changes by Arthur David Olson (primarily code changes)
   4179 
   4180   changes by Paul Eggert (primarily data changes)
   4181 
   4182   minor changes to "Makefile" and "northamerica" (in the latter case,
   4183   optimization of the "Toronto" rules)
   4184 
   4185 
   4186 Release 2003d - 2003-10-06 09:34:44 -0400
   4187 
   4188   changes by Paul Eggert
   4189 
   4190 
   4191 Release 2003c - 2003-09-16 10:47:05 -0400
   4192 
   4193   Fix bad returns in zic.c's inleap function.
   4194   Thanks to Bradley White for catching the problem!
   4195 
   4196 
   4197 Release 2003b - 2003-09-16 07:13:44 -0400
   4198 
   4199   Add a "--version" option (and documentation) to the zic and zdump commands.
   4200 
   4201   changes to overflow/underflow checking in zic
   4202 
   4203   a localtime typo fix.
   4204 
   4205   Update the leapseconds and tz-art.htm files.
   4206 
   4207 
   4208 Release 2003a - 2003-03-24 09:30:54 -0500
   4209 
   4210   changes by Paul Eggert
   4211 
   4212   a few additions and modifications to the tz-art.htm file
   4213 
   4214 
   4215 Release 2002d - 2002-10-15 13:12:42 -0400
   4216 
   4217   changes by Paul Eggert, less the "Britain (UK)" change in iso3166.tab
   4218 
   4219   There's also a new time zone quote in "tz-art.htm".
   4220 
   4221 
   4222 Release 2002c - 2002-04-04 11:55:20 -0500
   4223 
   4224   changes by Paul Eggert
   4225 
   4226   Change zic.c to avoid creating symlinks to files that don't exist.
   4227 
   4228 
   4229 Release 2002b - 2002-01-28 12:56:03 -0500
   4230 
   4231   [These change notes are for Release 2002a, which was corrupted.
   4232   2002b was a corrected version of 2002a.]
   4233 
   4234   changes by Paul Eggert
   4235 
   4236   Update the "leapseconds" file to note that there'll be no leap
   4237   second at the end of June, 2002.
   4238 
   4239   Change "zic.c" to deal with a problem in handling the "Asia/Bishkek" zone.
   4240 
   4241   Change to "difftime.c" to avoid sizeof problems.
   4242 
   4243 
   4244 Release 2001d - 2001-10-09 13:31:32 -0400
   4245 
   4246   changes by Paul Eggert
   4247 
   4248 
   4249 Release 2001c - 2001-06-05 13:59:55 -0400
   4250 
   4251   changes by Paul Eggert and Andrew Brown
   4252 
   4253 
   4254 Release 2001b - 2001-04-05 16:44:38 -0400
   4255 
   4256   changes by Paul Eggert (modulo jnorgard's typo fix)
   4257 
   4258   tz-art.htm has been HTMLified.
   4259 
   4260 
   4261 Release 2001a - 2001-03-13 12:57:44 -0500
   4262 
   4263   changes by Paul Eggert
   4264 
   4265   An addition to the "leapseconds" file: comments with the text of the
   4266   latest IERS leap second notice.
   4267 
   4268   Trailing white space has been removed from data file lines, and
   4269   repeated spaces in "Rule Jordan" lines in the "asia" file have been
   4270   converted to tabs.
   4271 
   4272 
   4273 Release 2000h - 2000-12-14 15:33:38 -0500
   4274 
   4275   changes by Paul Eggert
   4276 
   4277   one typo fix in the "art" file
   4278 
   4279   With providence, this is the last update of the millennium.
   4280 
   4281 
   4282 Release 2000g - 2000-10-10 11:35:22 -0400
   4283 
   4284   changes by Paul Eggert
   4285 
   4286   correction of John Mackin's name submitted by Robert Elz
   4287 
   4288   Garry Shandling's Daylight Saving Time joke (!?!) from the recent
   4289   Emmy Awards broadcast.
   4290 
   4291 
   4292 Release 2000f - 2000-08-10 09:31:58 -0400
   4293 
   4294   changes by Paul Eggert
   4295 
   4296   Added information in "tz-art.htm" on a Seinfeld reference to DST.
   4297 
   4298   Error checking and messages in the "yearistype" script have been
   4299   improved.
   4300 
   4301 
   4302 Release 2000e - 2000-07-31 09:27:54 -0400
   4303 
   4304   data changes by Paul Eggert
   4305 
   4306   a change to the default value of the defined constant HAVE_STRERROR
   4307 
   4308   the addition of a Dave Barry quote on DST to the tz-arts file
   4309 
   4310 
   4311 Release 2000d - 2000-04-20 15:43:04 -0400
   4312 
   4313   changes to the documentation and code of strftime for C99 conformance
   4314 
   4315   a bug fix for date.c
   4316 
   4317   These are based on (though modified from) changes by Paul Eggert.
   4318 
   4319 
   4320 Release 2000c - 2000-03-04 10:31:43 -0500
   4321 
   4322   changes by Paul Eggert
   4323 
   4324 
   4325 Release 2000b - 2000-02-21 12:16:29 -0500
   4326 
   4327   changes by Paul Eggert and Joseph Myers
   4328 
   4329   modest tweaks to the tz-art.htm and tz-link.htm files
   4330 
   4331 
   4332 Release 2000a - 2000-01-18 09:21:26 -0500
   4333 
   4334   changes by Paul Eggert
   4335 
   4336   The two hypertext documents have also been renamed.
   4337 
   4338 
   4339 Release code1999i-data1999j - 1999-11-15 18:43:22 -0500
   4340 
   4341   Paul Eggert's changes
   4342 
   4343   additions to the "zic" manual page and the "Arts.htm" file
   4344 
   4345 
   4346 Release code1999h-data1999i - 1999-11-08 14:55:21 -0500
   4347 
   4348   [not summarized]
   4349 
   4350 
   4351 Release data1999h - 1999-10-07 03:50:29 -0400
   4352 
   4353   changes by Paul Eggert to "europe" (most importantly, fixing
   4354   Lithuania and Estonia)
   4355 
   4356 
   4357 Release 1999g - 1999-09-28 11:06:18 -0400
   4358 
   4359   data changes by Paul Eggert (most importantly, the change for
   4360   Lebanon that buys correctness for this coming Sunday)
   4361 
   4362   The "code" file contains changes to "Makefile" and "checktab.awk" to
   4363   allow better checking of time zone files before they are published.
   4364 
   4365 
   4366 Release 1999f - 1999-09-23 09:48:14 -0400
   4367 
   4368   changes by Arthur David Olson and Paul Eggert
   4369 
   4370 
   4371 Release 1999e - 1999-08-17 15:20:54 -0400
   4372 
   4373   changes circulated by Paul Eggert, although the change to handling
   4374   of DST-specifying timezone names has been commented out for now
   4375   (search for "XXX" in "localtime.c" for details).  These files also
   4376   do not make any changes to the start of DST in Brazil.
   4377 
   4378   In addition to Paul's changes, there are updates to "Arts.htm" and
   4379   cleanups of URLs.
   4380 
   4381 
   4382 Release 1999d - 1999-03-30 11:31:07 -0500
   4383 
   4384   changes by Paul Eggert
   4385 
   4386   The Makefile's "make public" rule has also been changed to do a test
   4387   compile of each individual time zone data file (which should help
   4388   avoid problems such as the one we had with Nicosia).
   4389 
   4390 
   4391 Release 1999c - 1999-03-25 09:47:47 -0500
   4392 
   4393   changes by Paul Eggert, most importantly the change for Chile.
   4394 
   4395 
   4396 Release 1999b - 1999-02-01 17:51:44 -0500
   4397 
   4398   changes by Paul Eggert
   4399 
   4400   code changes (suggested by Mani Varadarajan, mani at be.com) for
   4401   correct handling of symbolic links when building using a relative directory
   4402 
   4403   code changes to generate correct messages for failed links
   4404 
   4405   updates to the URLs in Arts.htm
   4406 
   4407 
   4408 Release 1999a - 1999-01-19 16:20:29 -0500
   4409 
   4410   error message internationalizations and corrections in zic.c and
   4411   zdump.c (as suggested by Vladimir Michl, vladimir.michl at upol.cz,
   4412   to whom thanks!)
   4413 
   4414 
   4415 Release code1998h-data1998i - 1998-10-01 09:56:10 -0400
   4416 
   4417   changes for Brazil, Chile, and Germany
   4418 
   4419   support for use of "24:00" in the input files for the time zone compiler
   4420 
   4421 
   4422 Release code1998g-data1998h - 1998-09-24 10:50:28 -0400
   4423 
   4424   changes by Paul Eggert
   4425 
   4426   correction to a define in the "private.h" file
   4427 
   4428 
   4429 Release data1998g - 1998-08-11 03:28:35 -0000
   4430   [tzdata1998g.tar.gz is missing!]
   4431 
   4432   Lithuanian change provided by mgedmin at pub.osf.it
   4433 
   4434   Move creation of the GMT link with Etc/GMT to "etcetera" (from
   4435   "backward") to ensure that the GMT file is created even where folks
   4436   don't want the "backward" links (as suggested by Paul Eggert).
   4437 
   4438 
   4439 Release data1998f - 1998-07-20 13:50:00 -0000
   4440   [tzdata1998f.tar.gz is missing!]
   4441 
   4442   Update the "leapseconds" file to include the newly-announced
   4443   insertion at the end of 1998.
   4444 
   4445 
   4446 Release code1998f - 1998-06-01 10:18:31 -0400
   4447 
   4448   addition to localtime.c by Guy Harris
   4449 
   4450 
   4451 Release 1998e - 1998-05-28 09:56:26 -0400
   4452 
   4453   The Makefile is changed to produce zoneinfo-posix rather than
   4454   zoneinfo/posix, and to produce zoneinfo-leaps rather than
   4455   zoneinfo/right.
   4456 
   4457   data changes by Paul Eggert
   4458 
   4459   changes from Guy Harris to provide asctime_r and ctime_r
   4460 
   4461   A usno1998 file (substantially identical to usno1997) has been added.
   4462 
   4463 
   4464 Release 1998d - 1998-05-14 11:58:34 -0400
   4465 
   4466   changes to comments (in particular, elimination of references to CIA maps).
   4467   "Arts.htm", "WWW.htm", "asia", and "australasia" are the only places
   4468   where changes occur.
   4469 
   4470 
   4471 Release 1998c - 1998-02-28 12:32:26 -0500
   4472 
   4473   changes by Paul Eggert (save the "French correction," on which I'll
   4474   wait for the dust to settle)
   4475 
   4476   symlink changes
   4477 
   4478   changes and additions to Arts.htm
   4479 
   4480 
   4481 Release 1998b - 1998-01-17 14:31:51 -0500
   4482 
   4483   URL cleanups and additions
   4484 
   4485 
   4486 Release 1998a - 1998-01-13 12:37:35 -0500
   4487 
   4488   changes by Paul Eggert
   4489 
   4490 
   4491 Release code1997i-data1997k - 1997-12-29 09:53:41 -0500
   4492 
   4493   changes by Paul Eggert, with minor modifications from Arthur David
   4494   Olson to make the files more browser friendly
   4495 
   4496 
   4497 Release code1997h-data1997j - 1997-12-18 17:47:35 -0500
   4498 
   4499   minor changes to put "TZif" at the start of each timezone information file
   4500 
   4501   a rule has also been added to the Makefile so you can
   4502 	make zones
   4503   to just recompile the zone information files (rather than doing a
   4504   full "make install" with its other effects).
   4505 
   4506 
   4507 Release data1997i - 1997-10-07 08:45:38 -0400
   4508 
   4509   changes to Africa by Paul Eggert
   4510 
   4511 
   4512 Release code1997g-data1997h - 1997-09-04 16:56:54 -0400
   4513 
   4514   corrections for Uruguay (and other locations)
   4515 
   4516   Arthur David Olson's simple-minded fix allowing mktime to both
   4517   correctly handle leap seconds and correctly handle tm_sec values
   4518   upon which arithmetic has been performed.
   4519 
   4520 
   4521 Release code1997f-data1997g - 1997-07-19 13:15:02 -0400
   4522 
   4523   Paul Eggert's updates
   4524 
   4525   a small change to a function prototype;
   4526 
   4527   "Music" has been renamed "Arts.htm", HTMLified, and augmented to
   4528   include information on Around the World in Eighty Days.
   4529 
   4530 
   4531 Release code1997e-data1997f - 1997-05-03 18:52:34 -0400
   4532 
   4533   fixes to zic's error handling
   4534 
   4535   changes inspired by the item circulated on Slovenia
   4536 
   4537   The description of Web resources has been HTMLified for browsing
   4538   convenience.
   4539 
   4540   A new piece of tz-related music has been added to the "Music" file.
   4541 
   4542 
   4543 Release code1997d-data1997e - 1997-03-29 12:48:52 -0500
   4544 
   4545   Paul Eggert's latest suggestions
   4546 
   4547 
   4548 Release code1997c-data1997d - 1997-03-07 20:37:54 -0500
   4549 
   4550   changes to "zic.c" to correct performance of the "-s" option
   4551 
   4552   a new file "usno1997"
   4553 
   4554 
   4555 Release data1997c - 1997-03-04 09:58:18 -0500
   4556 
   4557   changes in Israel
   4558 
   4559 
   4560 Release 1997b - 1997-02-27 18:34:19 -0500
   4561 
   4562   The data file incorporates the 1997 leap second.
   4563 
   4564   The code file incorporates Arthur David Olson's take on the
   4565   zic/multiprocessor/directory-creation situation.
   4566 
   4567 
   4568 Release 1997a - 1997-01-21 09:11:10 -0500
   4569 
   4570   Paul Eggert's Antarctica (and other changes)
   4571 
   4572   Arthur David Olson finessed the "getopt" issue by checking against
   4573   both -1 and EOF (regardless of POSIX, SunOS 4.1.1's manual says -1
   4574   is returned while SunOS 5.5's manual says EOF is returned).
   4575 
   4576 
   4577 Release code1996o-data1996n - 1996-12-27 21:42:05 -0500
   4578 
   4579   Paul Eggert's latest changes
   4580 
   4581 
   4582 Release code1996n - 1996-12-16 09:42:02 -0500
   4583 
   4584   link snapping fix from Bruce Evans (via Garrett Wollman)
   4585 
   4586 
   4587 Release data1996m - 1996-11-24 02:37:34 -0000
   4588   [tzdata1996m.tar.gz is missing!]
   4589 
   4590   Paul Eggert's batch of changes
   4591 
   4592 
   4593 Release code1996m-data1996l - 1996-11-05 14:00:12 -0500
   4594 
   4595   No functional changes here; the files have simply been changed to
   4596   make more use of ISO style dates in comments. The names of the above
   4597   files now include the year in full.
   4598 
   4599 
   4600 Release code96l - 1996-09-08 17:12:20 -0400
   4601 
   4602   tzcode96k was missing a couple of pieces.
   4603 
   4604 
   4605 Release 96k - 1996-09-08 16:06:22 -0400
   4606 
   4607   the latest round of changes from Paul Eggert
   4608 
   4609   the recent Year 2000 material
   4610 
   4611 
   4612 Release code96j - 1996-07-30 13:18:53 -0400
   4613 
   4614   Set sp->typecnt as suggested by Timothy Patrick Murphy.
   4615 
   4616 
   4617 Release code96i - 1996-07-27 20:11:35 -0400
   4618 
   4619   Paul's suggested patch for strftime %V week numbers
   4620 
   4621 
   4622 Release data96i - 1996-07-01 18:13:04 -0400
   4623 
   4624   "northamerica" and "europe" changes by Paul Eggert
   4625 
   4626 
   4627 Release code96h - 1996-06-05 08:02:21 -0400
   4628 
   4629   fix for handling transitions specified in Universal Time
   4630 
   4631   Some "public domain" notices have also been added.
   4632 
   4633 
   4634 Release code96g - 1996-05-16 14:00:26 -0400
   4635 
   4636   fix for the simultaneous-DST-and-zone-change challenge
   4637 
   4638 
   4639 Release data96h - 1996-05-09 17:40:51 -0400
   4640 
   4641   changes by Paul Eggert
   4642 
   4643 
   4644 Release code96f-data96g - 1996-05-03 03:09:59 -0000
   4645   [tzcode96f.tar.gz + tzdata96g.tar.gz are both missing!]
   4646 
   4647   The changes get us some of the way to fixing the problems noted in Paul
   4648   Eggert's letter yesterday (in addition to a few others).  The approach
   4649   has been to make zic a bit smarter about figuring out what time zone
   4650   abbreviations apply just after the time specified in the "UNTIL" part
   4651   of a zone line.  Putting the smarts in zic means avoiding having
   4652   transition times show up in both "Zone" lines and "Rule" lines, which
   4653   in turn avoids multiple transition time entries in time zone files.
   4654   (This also makes the zic input files such as "europe" a bit shorter and
   4655   should ease maintenance.)
   4656 
   4657 
   4658 Release data96f - 1996-04-19 19:20:03 -0000
   4659   [tzdata96f.tar.gz is missing!]
   4660 
   4661   The only changes are to the "northamerica" file; the time zone
   4662   abbreviation for Denver is corrected to MST (and MDT), and the
   4663   comments for Mexico have been updated.
   4664 
   4665 
   4666 Release data96e - 1996-03-19 17:37:26 -0500
   4667 
   4668   Proposals by Paul Eggert, in particular the Portugal change that
   4669   comes into play at the end of this month.
   4670 
   4671 
   4672 Release data96d - 1996-03-18 20:49:39 -0500
   4673 
   4674   [not summarized]
   4675 
   4676 
   4677 Release code96e - 1996-02-29 15:43:27 -0000
   4678   [tzcode96e.tar.gz is missing!]
   4679 
   4680   internationalization changes and the fix to the documentation for strftime
   4681 
   4682 
   4683 Release code96d-data96c - 1996-02-12 11:05:27 -0500
   4684 
   4685   The "code" file simply updates Bob Kridle's electronic address.
   4686 
   4687   The "data" file updates rules for Mexico.
   4688 
   4689 
   4690 Release data96b - 1996-01-27 15:44:42 -0500
   4691 
   4692   Kiribati change
   4693 
   4694 
   4695 Release code96c - 1996-01-16 16:58:15 -0500
   4696 
   4697   leap-year streamlining and binary-search changes
   4698 
   4699   fix to newctime.3
   4700 
   4701 
   4702 Release code96b - 1996-01-10 20:42:39 -0500
   4703 
   4704   fixes and enhancements from Paul Eggert, including code that
   4705   emulates the behavior of recent versions of the SunOS "date"
   4706   command.
   4707 
   4708 
   4709 Release 96a - 1996-01-06 09:08:24 -0500
   4710 
   4711   Israel updates
   4712 
   4713   fixes to strftime.c for correct ISO 8601 week number generation,
   4714   plus support for two new formats ('G' and 'g') to give ISO 8601 year
   4715   numbers (which are not necessarily the same as calendar year numbers)
   4716 
   4717 
   4718 Release code95i-data95m - 1995-12-21 12:46:47 -0500
   4719 
   4720   The latest revisions from Paul Eggert are included, the usno1995
   4721   file has been updated, and a new file ("WWW") covering useful URLs
   4722   has been added.
   4723 
   4724 
   4725 Release code95h-data95l - 1995-12-19 18:10:12 -0500
   4726 
   4727   A simplification of a macro definition, a change to data for Sudan,
   4728   and (for last minute shoppers) notes in the "Music" file on the CD
   4729   "Old Man Time".
   4730 
   4731 
   4732 Release code95g-data95k - 1995-10-30 10:32:47 -0500
   4733 
   4734   (slightly reformatted) 8-bit-clean proposed patch
   4735 
   4736   minor patch: US/Eastern -> America/New_York
   4737 
   4738   snapshot of the USNO's latest data ("usno1995")
   4739 
   4740   some other minor cleanups
   4741 
   4742 
   4743 Release code95f-data95j - 1995-10-28 21:01:34 -0000
   4744   [tzcode95f.tar.gz + tzdata95j.tar.gz are both missing!]
   4745 
   4746   European cleanups
   4747 
   4748   support for 64-bit time_t's
   4749 
   4750   optimization in localtime.c
   4751 
   4752 
   4753 Release code95e - 1995-10-13 13:23:57 -0400
   4754 
   4755   the mktime change to scan from future to past when trying to find time zone
   4756   offsets
   4757 
   4758 
   4759 Release data95i - 1995-09-26 10:43:26 -0400
   4760 
   4761   For Canada/Central, guess that the Sun customer's "one week too
   4762   early" was just a approximation, and the true error is one month
   4763   too early.  This is consistent with the rest of Canada.
   4764 
   4765 
   4766 Release data95h - 1995-09-21 11:26:48 -0400
   4767 
   4768   latest changes from Paul Eggert
   4769 
   4770 
   4771 Release code95d - 1995-09-14 11:14:45 -0400
   4772 
   4773   the addition of a "Music" file, which documents four recorded
   4774   versions of the tune "Save That Time".
   4775 
   4776 
   4777 Release data95g - 1995-09-01 17:21:36 -0400
   4778 
   4779   "yearistype" correction
   4780 
   4781 
   4782 Release data95f - 1995-08-28 20:46:56 -0400
   4783 
   4784   Paul Eggert's change to the australasia file
   4785 
   4786 
   4787 Release data95e - 1995-07-08 18:02:34 -0400
   4788 
   4789   The only change is a leap second at the end of this year.
   4790   Thanks to Bradley White for forwarding news on the leap second.
   4791 
   4792 
   4793 Release data95d - 1995-07-03 13:26:22 -0400
   4794 
   4795   Paul Eggert's changes
   4796 
   4797 
   4798 Release data95c - 1995-07-02 19:19:28 -0400
   4799 
   4800   changes to "asia", "backward", "europe", and "southamerica"
   4801   (read: northamericacentrics need not apply)
   4802 
   4803 
   4804 Release code95c - 1995-03-13 14:00:46 -0500
   4805 
   4806   one-line fix for sign extension problems in detzcode
   4807 
   4808 
   4809 Release 95b - 1995-03-04 11:22:38 -0500
   4810 
   4811   Minor changes in both:
   4812 
   4813   The "code" file contains a workaround for the lack of "unistd.h" in
   4814   Microsoft C++ version 7.
   4815 
   4816   The "data" file contains a fixed "Link" for America/Shiprock.
   4817 
   4818 
   4819 Release 94h - 1994-12-10 12:51:14 -0500
   4820 
   4821   The files:
   4822 
   4823   *	incorporate the changes to "zdump" and "date" to make changes to
   4824 	the "TZ" environment variable permanent;
   4825 
   4826   *	incorporate the table changes by Paul Eggert;
   4827 
   4828   *	include (and document) support for universal time specifications in
   4829 	data files - but do not (yet) include use of this feature in the
   4830 	data files.
   4831 
   4832   Think of this as "TZ Classic" - the software has been set up not to break if
   4833   universal time shows up in its input, and data entries have been
   4834   left as is so as not to break existing implementations.
   4835 
   4836 
   4837 Release data94f - 1994-08-20 12:56:09 -0400
   4838 
   4839   (with thanks!) the latest data updates from Paul Eggert
   4840 
   4841 
   4842 Release data94e - 1994-06-04 13:13:53 -0400
   4843 
   4844   [not summarized]
   4845 
   4846 
   4847 Release code94g - 1994-05-05 12:14:07 -0400
   4848 
   4849   fix missing "optind.c" and a reference to it in the Makefile
   4850 
   4851 
   4852 Release code94f - 1994-05-05 13:00:33 -0000
   4853   [tzcode94f.tar.gz is missing!]
   4854 
   4855   changes to avoid overflow in difftime, as well as changes to cope
   4856   with the 52/53 challenge in strftime
   4857 
   4858 
   4859 Release code94e - 1994-03-30 23:32:59 -0500
   4860 
   4861   change for the benefit of PCTS
   4862 
   4863 
   4864 Release 94d - 1994-02-24 15:42:25 -0500
   4865 
   4866   Avoid clashes with POSIX semantics for zones such as GMT+4.
   4867 
   4868   Some other very minor housekeeping is also present.
   4869 
   4870 
   4871 Release code94c - 1994-02-10 08:52:40 -0500
   4872 
   4873   Fix bug where mkdirs was broken unless you compile with
   4874   -fwritable-strings (which is generally losing to do).
   4875 
   4876 
   4877 Release 94b - 1994-02-07 10:04:33 -0500
   4878 
   4879   work by Paul Eggert who notes:
   4880 
   4881   I found another book of time zone histories by E W Whitman; it's not
   4882   as extensive as Shanks but has a few goodies of its own.  I used it
   4883   to update the tables.  I also fixed some more as a result of
   4884   correspondence with Adam David and Peter Ilieve, and move some stray
   4885   links from 'europe' to 'backward'.  I corrected some scanning errors
   4886   in usno1989.
   4887 
   4888   As far as the code goes, I fixed zic to allow years in the range
   4889   INT_MIN to INT_MAX; this fixed a few boundary conditions around 1900.
   4890   And I cleaned up the zic documentation a little bit.
   4891 
   4892 
   4893 Release data94a - 1994-02-03 08:58:54 -0500
   4894 
   4895   It simply incorporates the recently announced leap second into the
   4896   "leapseconds" file.
   4897 
   4898 
   4899 Release 93g - 1993-11-22 17:28:27 -0500
   4900 
   4901   Paul Eggert has provided a good deal of historic information (based
   4902   on Shanks), and there are some code changes to deal with the buglets
   4903   that crawled out in dealing with the new information.
   4904 
   4905 
   4906 Release 93f - 1993-10-15 12:27:46 -0400
   4907 
   4908   Paul Eggert's changes
   4909 
   4910 
   4911 Release 93e - 1993-09-05 21:21:44 -0400
   4912 
   4913   This has updated data for Israel, England, and Kwajalein.  There's
   4914   also an update to "zdump" to cope with Kwajalein's 24-hour jump.
   4915   Thanks to Paul Eggert and Peter Ilieve for the changes.
   4916 
   4917 
   4918 Release 93d - 1993-06-17 23:34:17 -0400
   4919 
   4920   new fix and new data on Israel
   4921 
   4922 
   4923 Release 93c - 1993-06-06 19:31:55 -0400
   4924 
   4925   [not summarized]
   4926 
   4927 
   4928 Release 93b - 1993-02-02 14:53:58 -0500
   4929 
   4930   updated "leapseconds" file
   4931 
   4932 
   4933 Release 93 - 1993-01-08 07:01:06 -0500
   4934 
   4935   At kre's suggestion, the package has been split in two - a code piece
   4936   (which also includes documentation) that's only of use to folks who
   4937   want to recompile things and a data piece useful to anyone who can
   4938   run "zic".
   4939 
   4940   The new version has a few changes to the data files, a few
   4941   portability changes, and an off-by-one fix (with thanks to
   4942   Tom Karzes at deshaw.com for providing a description and a
   4943   solution).
   4944 
   4945 
   4946 Release 92c - 1992-11-21 17:35:36 -0000
   4947   [tz92c.tar.Z is missing!]
   4948 
   4949   The fallout from the latest round of DST transitions.
   4950 
   4951   There are changes for Portugal, Saskatchewan, and "Pacific-New";
   4952   there's also a change to "zic.c" that makes it portable to more systems.
   4953 
   4954 
   4955 Release 92 - 1992-04-25 18:17:03 -0000
   4956   [tz92.tar.Z is missing!]
   4957 
   4958   By popular demand (well, at any rate, following a request by kre at munnari)
   4959 
   4960 
   4961 The 1989 update of the time zone package featured:
   4962 
   4963   *	POSIXization (including interpretation of POSIX-style TZ environment
   4964 	variables, provided by Guy Harris),
   4965   *	ANSIfication (including versions of "mktime" and "difftime"),
   4966   *	SVIDulation (an "altzone" variable)
   4967   *	MACHination (the "gtime" function)
   4968   *	corrections to some time zone data (including corrections to the rules
   4969 	for Great Britain and New Zealand)
   4970   *	reference data from the United States Naval Observatory for folks who
   4971 	want to do additional time zones
   4972   *	and the 1989 data for Saudi Arabia.
   4973 
   4974   (Since this code will be treated as "part of the implementation" in some
   4975   places and as "part of the application" in others, there's no good way to
   4976   name functions, such as timegm, that are not part of the proposed ANSI C
   4977   standard; such functions have kept their old, underscore-free names in this
   4978   update.)
   4979 
   4980   And the "dysize" function has disappeared; it was present to allow
   4981   compilation of the "date" command on old BSD systems, and a version of "date"
   4982   is now provided in the package.  The "date" command is not created when you
   4983   "make all" since it may lack options provided by the version distributed with
   4984   your operating system, or may not interact with the system in the same way
   4985   the native version does.
   4986 
   4987   Since POSIX frowns on correct leap second handling, the default behavior of
   4988   the "zic" command (in the absence of a "-L" option) has been changed to omit
   4989   leap second information from its output files.
   4990 
   4991 
   4992 -----
   4993 Notes
   4994 
   4995 This file contains copies of the part of each release announcement
   4996 that talks about the changes in that release.  The text has been
   4997 adapted and reformatted for the purposes of this file.
   4998 
   4999 Traditionally a release R consists of a pair of tarball files,
   5000 tzcodeR.tar.gz and tzdataR.tar.gz.  However, some releases (e.g.,
   5001 code2010a, data2012c) consist of just one or the other tarball, and a
   5002 few (e.g., code2012c-data2012d) have tarballs with mixed version
   5003 numbers.  Recent releases also come in an experimental format
   5004 consisting of a single tarball tzdb-R.tar.lz with extra data.
   5005 
   5006 Release timestamps are taken from the release's commit (for newer,
   5007 Git-based releases), from the newest file in the tarball (for older
   5008 releases, where this info is available) or from the email announcing
   5009 the release (if all else fails; these are marked with a time zone
   5010 abbreviation of -0000 and an "is missing!" comment).
   5011 
   5012 Earlier versions of the code and data were not announced on the tz
   5013 list and are not summarized here.
   5014 
   5015 This file is in the public domain.
   5016 
   5017 Local Variables:
   5018 coding: utf-8
   5019 End:
   5020