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Annotation of src/lib/libc/time/NEWS, Revision 1.29

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

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