June 2014 - tz - lists.iana.org

proposed time zone package changes (Samoa, Factory, et al.)
by Arthur David Olson Aug. 28, 2019

Aug. 28, 2019

Below find proposed time zone package changes; the executive summary: * Makefile Change LOCALTIME default from "Factory" to "GMT"; do not compile "factory" file (but keep it in the distribution). * Theory Remove reference to "Factory" zone. * australasia Change end of DST in Samoa in 2011 from 2011-04-03 0:00 to 2011-04-03 1:00 (thanks to Raymond Hughes for a reference). * localtime.c Initialize ttinfo structures filled by tzparse (thanks to Ravindra for reporting a valgrind warning). * zic.c Fix generation of POSIX strings for zones with rules using "weekday<=n" forms of dates (thanks to Lei Liu for finding the problem). Also, limit output for non-POSIX-specificable zones defined to follow the same rules every year. (Note that no zones of either of the above types appear in the distribution; these changes cater to add-on zones). If no problems are found, 2010n will appear on 2010-10-25. --ado diff -r -c old/Makefile new/Makefile *** old/Makefile Mon Sep 27 09:24:25 2010 --- new/Makefile Tue Oct 12 12:36:50 2010 *************** *** 1,5 **** # <pre> ! # @(#)Makefile 8.8 # This file is in the public domain, so clarified as of # 2009-05-17 by Arthur David Olson. --- 1,5 ---- # <pre> ! # @(#)Makefile 8.9 # This file is in the public domain, so clarified as of # 2009-05-17 by Arthur David Olson. *************** *** 12,18 **** # make zonenames # to get a list of the values you can use for LOCALTIME. ! LOCALTIME= Factory # If you want something other than Eastern United States time as a template # for handling POSIX-style time zone environment variables, --- 12,18 ---- # make zonenames # to get a list of the values you can use for LOCALTIME. ! LOCALTIME= GMT # If you want something other than Eastern United States time as a template # for handling POSIX-style time zone environment variables, *************** *** 262,269 **** DOCS= README Theory $(MANS) date.1 Makefile PRIMARY_YDATA= africa antarctica asia australasia \ europe northamerica southamerica ! YDATA= $(PRIMARY_YDATA) pacificnew etcetera factory backward ! NDATA= systemv SDATA= solar87 solar88 solar89 TDATA= $(YDATA) $(NDATA) $(SDATA) TABDATA= iso3166.tab zone.tab --- 262,269 ---- DOCS= README Theory $(MANS) date.1 Makefile PRIMARY_YDATA= africa antarctica asia australasia \ europe northamerica southamerica ! YDATA= $(PRIMARY_YDATA) pacificnew etcetera backward ! NDATA= systemv factory SDATA= solar87 solar88 solar89 TDATA= $(YDATA) $(NDATA) $(SDATA) TABDATA= iso3166.tab zone.tab diff -r -c old/Theory new/Theory *** old/Theory Mon Sep 27 09:24:25 2010 --- new/Theory Tue Oct 12 12:36:50 2010 *************** *** 1,4 **** ! @(#)Theory 8.4 This file is in the public domain, so clarified as of 2009-05-17 by Arthur David Olson. --- 1,4 ---- ! @(#)Theory 8.5 This file is in the public domain, so clarified as of 2009-05-17 by Arthur David Olson. *************** *** 287,294 **** See the file `backward' for most of these older names (e.g. `US/Eastern' instead of `America/New_York'). The other old-fashioned names still supported are ! `WET', `CET', `MET', `EET' (see the file `europe'), ! and `Factory' (see the file `factory'). ----- Time zone abbreviations ----- --- 287,293 ---- See the file `backward' for most of these older names (e.g. `US/Eastern' instead of `America/New_York'). The other old-fashioned names still supported are ! `WET', `CET', `MET', and `EET' (see the file `europe'). ----- Time zone abbreviations ----- diff -r -c old/australasia new/australasia *** old/australasia Mon Sep 27 09:24:27 2010 --- new/australasia Tue Oct 12 13:14:56 2010 *************** *** 1,5 **** # <pre> ! # @(#)australasia 8.18 # This file is in the public domain, so clarified as of # 2009-05-17 by Arthur David Olson. --- 1,5 ---- # <pre> ! # @(#)australasia 8.19 # This file is in the public domain, so clarified as of # 2009-05-17 by Arthur David Olson. *************** *** 487,497 **** # http://www.parliament.gov.ws/documents/acts/Daylight%20Saving%20Act%20%2020… # </a> Zone Pacific/Apia 12:33:04 - LMT 1879 Jul 5 -11:26:56 - LMT 1911 -11:30 - SAMT 1950 # Samoa Time -11:00 - WST 2010 Sep 26 ! -11:00 1:00 WSDT 2011 Apr 3 -11:00 - WST # Solomon Is --- 487,507 ---- # http://www.parliament.gov.ws/documents/acts/Daylight%20Saving%20Act%20%2020… # </a> + # From Raymond Hughes (2010-10-07): + # Please see + # <a href="http://www.mcil.gov.ws"> + # http://www.mcil.gov.ws + # </a>, + # the Ministry of Commerce, Industry and Labour (sideframe) "Last Sunday + # September 2010 (26/09/10) - adjust clocks forward from 12:00 midnight + # to 01:00am and First Sunday April 2011 (03/04/11) - adjust clocks + # backwards from 1:00am to 12:00am" + Zone Pacific/Apia 12:33:04 - LMT 1879 Jul 5 -11:26:56 - LMT 1911 -11:30 - SAMT 1950 # Samoa Time -11:00 - WST 2010 Sep 26 ! -11:00 1:00 WSDT 2011 Apr 3 1:00 -11:00 - WST # Solomon Is diff -r -c old/localtime.c new/localtime.c *** old/localtime.c Mon Sep 27 09:24:26 2010 --- new/localtime.c Tue Oct 12 12:36:51 2010 *************** *** 5,11 **** #ifndef lint #ifndef NOID ! static char elsieid[] = "@(#)localtime.c 8.14"; #endif /* !defined NOID */ #endif /* !defined lint */ --- 5,11 ---- #ifndef lint #ifndef NOID ! static char elsieid[] = "@(#)localtime.c 8.15"; #endif /* !defined NOID */ #endif /* !defined lint */ *************** *** 914,919 **** --- 914,920 ---- register unsigned char * typep; register char * cp; register int load_result; + static struct ttinfo zttinfo; INITIALIZE(dstname); stdname = name; *************** *** 986,991 **** --- 987,993 ---- /* ** Two transitions per year, from EPOCH_YEAR forward. */ + sp->ttis[0] = sp->ttis[1] = zttinfo; sp->ttis[0].tt_gmtoff = -dstoffset; sp->ttis[0].tt_isdst = 1; sp->ttis[0].tt_abbrind = stdlen + 1; *************** *** 1099,1106 **** } /* ** Finally, fill in ttis. - ** ttisstd and ttisgmt need not be handled. */ sp->ttis[0].tt_gmtoff = -stdoffset; sp->ttis[0].tt_isdst = FALSE; sp->ttis[0].tt_abbrind = 0; --- 1101,1108 ---- } /* ** Finally, fill in ttis. */ + sp->ttis[0] = sp->ttis[1] = zttinfo; sp->ttis[0].tt_gmtoff = -stdoffset; sp->ttis[0].tt_isdst = FALSE; sp->ttis[0].tt_abbrind = 0; *************** *** 1113,1118 **** --- 1115,1121 ---- dstlen = 0; sp->typecnt = 1; /* only standard time */ sp->timecnt = 0; + sp->ttis[0] = zttinfo; sp->ttis[0].tt_gmtoff = -stdoffset; sp->ttis[0].tt_isdst = 0; sp->ttis[0].tt_abbrind = 0; diff -r -c old/zic.c new/zic.c *** old/zic.c Mon Sep 27 09:24:26 2010 --- new/zic.c Tue Oct 12 13:37:29 2010 *************** *** 3,9 **** ** 2006-07-17 by Arthur David Olson. */ ! static char elsieid[] = "@(#)zic.c 8.22"; #include "private.h" #include "locale.h" --- 3,9 ---- ** 2006-07-17 by Arthur David Olson. */ ! static char elsieid[] = "@(#)zic.c 8.24"; #include "private.h" #include "locale.h" *************** *** 1881,1896 **** register int week; if (rp->r_dycode == DC_DOWGEQ) { ! week = 1 + rp->r_dayofmonth / DAYSPERWEEK; ! if ((week - 1) * DAYSPERWEEK + 1 != rp->r_dayofmonth) return -1; } else if (rp->r_dycode == DC_DOWLEQ) { if (rp->r_dayofmonth == len_months[1][rp->r_month]) week = 5; else { ! week = 1 + rp->r_dayofmonth / DAYSPERWEEK; ! if (week * DAYSPERWEEK - 1 != rp->r_dayofmonth) return -1; } } else return -1; /* "cannot happen" */ (void) sprintf(result, "M%d.%d.%d", --- 1881,1896 ---- register int week; if (rp->r_dycode == DC_DOWGEQ) { ! if ((rp->r_dayofmonth % DAYSPERWEEK) != 1) return -1; + week = 1 + rp->r_dayofmonth / DAYSPERWEEK; } else if (rp->r_dycode == DC_DOWLEQ) { if (rp->r_dayofmonth == len_months[1][rp->r_month]) week = 5; else { ! if ((rp->r_dayofmonth % DAYSPERWEEK) != 0) return -1; + week = rp->r_dayofmonth / DAYSPERWEEK; } } else return -1; /* "cannot happen" */ (void) sprintf(result, "M%d.%d.%d", *************** *** 2018,2023 **** --- 2018,2024 ---- register char * envvar; register int max_abbr_len; register int max_envvar_len; + register int prodstic; /* all rules are min to max */ max_abbr_len = 2 + max_format_len + max_abbrvar_len; max_envvar_len = 2 * max_abbr_len + 5 * 9; *************** *** 2032,2037 **** --- 2033,2039 ---- timecnt = 0; typecnt = 0; charcnt = 0; + prodstic = zonecount == 1; /* ** Thanks to Earl Chew ** for noting the need to unconditionally initialize startttisstd. *************** *** 2053,2058 **** --- 2055,2062 ---- updateminmax(rp->r_loyear); if (rp->r_hiwasnum) updateminmax(rp->r_hiyear); + if (rp->r_lowasnum || rp->r_hiwasnum) + prodstic = FALSE; } } /* *************** *** 2075,2080 **** --- 2079,2094 ---- if (max_year <= INT_MAX - YEARSPERREPEAT) max_year += YEARSPERREPEAT; else max_year = INT_MAX; + /* + ** Regardless of any of the above, + ** for a "proDSTic" zone which specifies that its rules + ** always have and always will be in effect, + ** we only need one cycle to define the zone. + */ + if (prodstic) { + min_year = 1900; + max_year = min_year + YEARSPERREPEAT; + } } /* ** For the benefit of older systems,

5 6

zic changes (2/2)
by Arthur David Olson March 9, 2016

March 9, 2016

And now, the update. These changes arrange things so that binary files include "transition" entries for minimum time values; these entries eliminate localtime guesswork in handling low-valued time stamps. The bad news: binary files grow slightly as a result of these changes. The good news: there are no changes in the output of "zdump -v" applied to before-and-after versions of all the binary files generated by a "make install." Changes are attached and appear in mangled form below; these are relative to the github version of zic.c after the rollback in the earlier message today. @dashdashado 1.2 2805 lines 1.4 2813 lines *** /tmp/,azic.c 2014-05-01 01:51:36.998933800 -0400 --- /tmp/,bzic.c 2014-05-01 01:51:37.092534000 -0400 *************** *** 1480,1493 **** fromi = 0; while (fromi < timecnt && attypes[fromi].at < min_time) ++fromi; - if (isdsts[0] == 0) - while (fromi < timecnt && attypes[fromi].type == 0) - ++fromi; /* handled by default rule */ for ( ; fromi < timecnt; ++fromi) { ! if (toi != 0 && ((attypes[fromi].at + gmtoffs[attypes[toi - 1].type]) <= ! (attypes[toi - 1].at + gmtoffs[toi == 1 ? 0 ! : attypes[toi - 2].type]))) { attypes[toi - 1].type = attypes[fromi].type; continue; --- 1480,1490 ---- fromi = 0; while (fromi < timecnt && attypes[fromi].at < min_time) ++fromi; for ( ; fromi < timecnt; ++fromi) { ! if (toi > 1 && ((attypes[fromi].at + gmtoffs[attypes[toi - 1].type]) <= ! (attypes[toi - 1].at + ! gmtoffs[attypes[toi - 2].type]))) { attypes[toi - 1].type = attypes[fromi].type; continue; *************** *** 1532,1537 **** --- 1529,1541 ---- --timecnt32; ++timei32; } + /* + ** Output an INT32_MIN "transition" if appropriate--see below. + */ + if (timei32 > 0 && ats[timei32] > INT32_MIN) { + --timei32; + ++timecnt32; + } while (leapcnt32 > 0 && !is32(trans[leapcnt32 - 1])) --leapcnt32; while (leapcnt32 > 0 && !is32(trans[leapi32])) { *************** *** 1698,1704 **** #undef DO for (i = thistimei; i < thistimelim; ++i) if (pass == 1) ! puttzcode(ats[i], fp); else puttzcode64(ats[i], fp); for (i = thistimei; i < thistimelim; ++i) { unsigned char uc; --- 1702,1713 ---- #undef DO for (i = thistimei; i < thistimelim; ++i) if (pass == 1) ! /* ! ** Output an INT32_MIN "transition" ! ** if appropriate--see above. ! */ ! puttzcode(((ats[i] < INT32_MIN) ? ! INT32_MIN : ats[i]), fp); else puttzcode64(ats[i], fp); for (i = thistimei; i < thistimelim; ++i) { unsigned char uc; *************** *** 2176,2183 **** if (usestart) { addtt(starttime, type); usestart = FALSE; ! } else if (stdoff != 0) ! addtt(min_time, type); } else for (year = min_year; year <= max_year; ++year) { if (useuntil && year > zp->z_untilrule.r_hiyear) break; --- 2185,2191 ---- if (usestart) { addtt(starttime, type); usestart = FALSE; ! } else addtt(min_time, type); } else for (year = min_year; year <= max_year; ++year) { if (useuntil && year > zp->z_untilrule.r_hiyear) break;

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proposed tz change for Latvia, Lithuania
by Paul Eggert May 25, 2015

May 25, 2015

It's March Madness time for daylight-saving rule changes. Here's a proposed change to the tz database to keep up with the latest political development, which affects time stamps starting March 29: * Latvia and Lithuania will not observe DST, starting this year. Thanks to Andrei Ivanov for this info. =================================================================== RCS file: RCS/europe,v retrieving revision 2000.3 retrieving revision 2000.3.0.1 diff -pu -r2000.3 -r2000.3.0.1 --- europe 2000/03/04 15:31:08 2000.3 +++ europe 2000/03/08 17:48:59 2000.3.0.1 @@ -1135,6 +1135,12 @@ Link Europe/Rome Europe/San_Marino # 1997-01-21 on transition to Summer time ... established the same order of # daylight savings time settings as in the States of the European Union. +# From Andrei Ivanov (2000-03-06): +# This year Latvia will not switch to Daylight Savings Time (as specified in +# <a href="http://www.lv-laiks.lv/wwwraksti/2000/071072/vd4.htm"> +# The Regulations of the Cabinet of Ministers of the Rep. of Latvia of +# 29-Feb-2000 (#79)</a>, in Latvian for subscribers only). + # Rule NAME FROM TO TYPE IN ON AT SAVE LETTER/S Rule Latvia 1989 1996 - Mar lastSun 2:00s 1:00 S Rule Latvia 1989 1996 - Sep lastSun 2:00s 0 - @@ -1151,7 +1157,8 @@ Zone Europe/Riga 1:36:24 - LMT 1880 3:00 Russia MSK/MSD 1989 Mar lastSun 2:00s 2:00 1:00 EEST 1989 Sep lastSun 2:00s 2:00 Latvia EE%sT 1997 Jan 21 - 2:00 EU EE%sT + 2:00 EU EE%sT 2000 Feb 29 + 2:00 - EET # Liechtenstein # Zone NAME GMTOFF RULES FORMAT [UNTIL] @@ -1178,6 +1185,11 @@ Zone Europe/Vaduz 0:38:04 - LMT 1894 Jun # motion to give up shifting to summer time in spring, as it was # already done by Estonia. +# From Andrei Ivanov (2000-03-06): +# I've heard that Ministers of three Baltic countries on their summit +# somewhere in February decided not to switch to summer time starting from +# this spring. + # Zone NAME GMTOFF RULES FORMAT [UNTIL] Zone Europe/Vilnius 1:41:16 - LMT 1880 1:24:00 - WMT 1917 # Warsaw Mean Time @@ -1192,7 +1204,8 @@ Zone Europe/Vilnius 1:41:16 - LMT 1880 2:00 C-Eur EE%sT 1998 2:00 - EET 1998 Mar 29 1:00u 1:00 EU CE%sT 1999 Oct 31 1:00u - 2:00 EU EE%sT + 2:00 EU EE%sT 2000 Feb + 2:00 - EET # Luxembourg # Whitman disagrees with most of these dates in minor ways; go with Shanks.

5 5

Adding Asia/Beijing timezone into the database
by Daoming Qiu Dec. 6, 2014

Dec. 6, 2014

"Beijing Time" is the standard time used for China region, so it is very strange that tzdatabase doesn't have timezone called Asia/Beijing. Strongly suggest to add "Asia/Beijing" zone into the database, and its information is very similar with "Asia/Shanghai".

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[PATCH1/1] Propose new zone for Crozet Islands
by Antoine Leca July 8, 2014

July 8, 2014

Crozet Islands have a year-round scientific base (Alfred-Faure) since 1964. Also corrected the geographic coordinates. Noticed by Tobias Conradi <http://mm.icann.org/pipermail/tz/2012-May/017804.html> --- antarctica | 8 +++++++- zone.tab | 3 ++- 2 files changed, 9 insertions(+), 2 deletions(-) diff --git a/antarctica b/antarctica index 9bf2494..7190413 100644 --- a/antarctica +++ b/antarctica @@ -169,7 +169,6 @@ Zone Antarctica/Mawson 0 - zzz 1954 Feb 13 # French Southern Territories with year-round inhabitants # # Martin-de-Vivies Base, Amsterdam Island, -374105+0773155, since 1950 -# Alfred-Faure Base, Crozet Islands, -462551+0515152, since 1964 # Port-aux-Francais, Kerguelen Islands, -492110+0701303, since 1951; # whaling & sealing station operated 1908/1914, 1920/1929, and 1951/1956 # @@ -179,6 +178,13 @@ Zone Antarctica/Mawson 0 - zzz 1954 Feb 13 # Zone NAME GMTOFF RULES FORMAT [UNTIL] Zone Indian/Kerguelen 0 - zzz 1950 # Port-aux-Francais 5:00 - TFT # ISO code TF Time + +# Alfred-Faure Base, Crozet Islands, -462551+0515125, since 1964 +# sealing & whaling stations operated variously 1802/1911+ +# Zone NAME GMTOFF RULES FORMAT [UNTIL] +Zone Indian/Alfred-Faure 0 - zzz 1963 + 4:00 - AFT # Alfred-Faure Time + # # year-round base in the main continent # Dumont-d'Urville, Ile des Petrels, -6640+14001, since 1956-11 diff --git a/zone.tab b/zone.tab index 6b98520..0f34698 100644 --- a/zone.tab +++ b/zone.tab @@ -373,7 +373,8 @@ SY +3330+03618 Asia/Damascus SZ -2618+03106 Africa/Mbabane TC +2128-07108 America/Grand_Turk TD +1207+01503 Africa/Ndjamena -TF -492110+0701303 Indian/Kerguelen +TF -492110+0701303 Indian/Kerguelen most locations +TF -462551+0515125 Indian/Alfred-Faure Crozet Islands TG +0608+00113 Africa/Lome TH +1345+10031 Asia/Bangkok TJ +3835+06848 Asia/Dushanbe -- 1.8.0.msysgit.0

2 1

About Time Zone in Asia/Taipei During World War 2
by Yu-Cheng Chuang July 4, 2014

July 4, 2014

Hello, I'm Yu-Cheng Chuang, a Taiwanese, and also a programmer. I just studied some knowledge about the time zone, and found that there is a commonly-used database maintained by IANA, which is widely used in our UNIX-like OS as well as software systems. I'm a Rails developer, and the TZInfo library derived from the Time Zone Database helped me a lot when building a time-zone-aware feature. It's really very useful. Thank you for making it. When studying these knowledge, as a Taiwanese, I found that during the Japanese era (1895-1945), time zone in Taiwan was mostly UTC+8 (Western Standard Time). However, during the World War II, as a part of Japan, the Japanese emperor ordered that the whole country should adopt the Central Standard Time (UTC+9), including Taiwan as well as overseas territories occupied later during the war (e.g. Hong Kong, Singapore). In the Time Zone database, I found that such fact is recorded on the time zones of its occupied cities: * Hong Kong * Singapore * Rangoon in Myanmar * Dili in East Timor * Jakarta, Pontianak and Makassar in Indonesia * Kuala Lumpur and Kuching in Malaysia * Manila in Philippines However, here Taipei in Taiwan is missing, which during the World War II was still a territory of Japan, and switched to UTC+9 since Oct 1, 1937. In addition, I see that in the section of Japan, Hideyuki Suzuki mentioned Western Standard Time, which was declared in 1895, in the Meiji 19 year ordinance No. 167. I think its declaration might be due to the annexation of Taiwan. Here is a brief history from Wikipedia (http://en.wikipedia.org/wiki/Japanese_invasion_of_Taiwan_(1895)) * On April 17, 1895, the Qing Dynasty of China ceded Taiwan and Penghu Islands to Japan. * On May 27, 1895, the Japanese army landed Taiwan, the invasion began. * On Nov 18, 1895, the Taiwan General (from Japan) reported "the whole island is capitulated" to the Japan central government. Then, On Dec 28, 1895, the Meiji Emperor announced Ordinance No. 167 of Meiji Year 28 "The clause about standard time", mentioned that Taiwan and Penghu Islands, as well as Yaeyama and Miyako Islands (both in Okinawa) adopt the Western Standard Time which is based on 120E. The adoption began from Jan 1, 1896. (The original text can be found on Wikisource (http://ja.wikisource.org/wiki/%E6%A8%99%E6%BA%96%E6%99%82%E3%83%8B%E9%97%9C…) However I don't know Japanese language very well; the only way I understand it is through Kanji and Google Translate.) This could be the first adoption of time zone in Taiwan, because during the Qing Dynasty, it seems that there was no time zone declared officially. Later, in the beginning of World War II, on Sep 25, 1937, the Showa Emperor announced Ordinance No. 529 of Showa Year 12 "The clause of revision in the ordinance No. 167 of Meiji year 28 about standard time", in which abolished the adoption of Western Standard Time in western islands (listed above), which means the whole Japan territory, including later occupations, adopt Japan Central Time (UTC+9). The adoption began on Oct 1, 1937. (The original text can be found on Wikisource (http://ja.wikisource.org/wiki/%E6%98%8E%E6%B2%BB%E4%BA%8C%E5%8D%81%E5%85%AB….) That is, the time zone of Taipei switched to UTC+9 on Oct 1, 1937. Of course, after the surrender of Japan, time zone of Taiwan switched back to UTC+8. However I can't find enough evidence to tell when the switch happened. The only thing I know is that the official surrender ceremony is on Oct 25, 1945. From then, Taiwan and Penghu islands are territories of the Republic of China, until now. Again, I only know a little bit Japanese, and as a native Chinese speaker, the only words I can read are nouns written in Kanji (Chinese chars). Therefore, I may misunderstand the Japanese ordinances, but I believe I read them mostly correctly because in that time, most Japanese people write Chinese-like Japanese. I think it would be better to have someone who know Japanese read them directly. Please correct me if I misunderstood anything. I hope that the history above helps you improve the Time Zone database. Sincerely, Yu-Cheng Chuang p.s. References from Wikisource: * Ordinance No. 167 of Meiji Year 28: http://ja.wikisource.org/wiki/%E6%A8%99%E6%BA%96%E6%99%82%E3%83%8B%E9%97%9C… * Ordinance No. 529 of Showa Year 12: http://ja.wikisource.org/wiki/%E6%98%8E%E6%B2%BB%E4%BA%8C%E5%8D%81%E5%85%AB…

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China time zones 1949 - 1980: appeal to speakers of Mandarin
by Alois Treindl July 3, 2014

July 3, 2014

tz database holds that People's Republic of China maintained 5 different time zones between the foundation of the PRC in 1949 and May 1980, when the uniform Beijing timezone (GMT + 8h) was introduced. Various sources claim that this unified country-wide timezone was already introduced in 1949 or early 1950: Several TZ mailing list entries, e.g. 10/16/2010 by Jonathan.Hassid(a)uts.edu.au who writes: "The government in Chengdu (capital of Sichuan province) announced the switch (from "Shulong" (Gansu/Sichuan) time) to Beijing time on 27 Dec. 1949. The rest of the country followed "in early 1950" (dates unspecified), and as I mentioned in my last email, "by the beginning of 1950, within a few months after establishing the country, the entire country except for Xinjiang and Tibet was all using the Beijing Time standard." Paul Eckert tried to get an answer from historian Thomas S Mullaney in a correspondence in February 2008, but the question whether China introduced the unified timezone in 1949 or 1980 remained unanswered by Mullaney (he is currently on leave from Stanford and cannot be contacted). The Wikipedia articles 'Time in China' http://en.wikipedia.org/wiki/Time_in_China and 'Historical time zones of China' http://en.wikipedia.org/wiki/Historical_time_zones_of_China hold that the unified timezone was introduced in 1949. They say: "These time zones were no longer in effective use after 1949, in the Chinese Civil War when the People's Republic of China was established on mainland China. The People's Republic of China uses a single time zone (GMT+8) for the whole country," and "After the Chinese Civil War in 1949, the People's Republic of China established one single time zone (UTC+8) for the entirety of its claimed territories, " I could not identify the source reference for this claim by the Wikipedia authors. I tried to contact one of them, User:Alanmak by various means without success. He seemed to me the main contributor regarding China TZ history. This seems to be a relevant source: Guo, Qingsheng (2003) "Beijing Time at the Beginning of PRC", China Historical Materials of Science and Technology 24(1) It is an article in Chinese (it can be purchased online), and I do not know a translator whom I would trust with translation of such technical or historical detail. It seems to me that the only source claiming the continuation of 5 time zones for China is the International Atlas by Shanks and Pottenger. The overall work of these authors is extremely valuable, but they do not give a source for their China information. Paul Eckert says in tz/asia file: # From Paul Eggert (2008-06-30): # There seems to be a good chance China switched to a single time zone in 1949 # rather than in 1980 as Shanks & Pottenger have it, but we don't have a # reliable documentary source saying so yet, so for now we still go with # Shanks & Pottenger. I agree with Paul's opinion and decision, but find it not acceptable to remain at this degree of uncertainty or such a large area, long time period of 31 years and such a large population of hundreds of millions of people: We do NOT reliably know which timezone there was in January 1980 in large cities like Chengdu or Chongqing. I appeal to those readers of the mailing list capable of reading Chinese / mandarin to look for sources which could - document that multiple timezones where indeed maintained before May 1980 (e.g. railway or airline time tables of that period), - document the transition to a unified zone in May 1980 (legal text, newspaper articles mentioning the time change) - document the government decision for a unified timezone in 1949 My gut feeling is that the unified timezone was introduced in 1949, and that Shanks got it wrong. We need documents to establish that.

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[PATCH] More spelling and accent fixes.
by vanadovv＠hetnet.nl July 2, 2014

July 2, 2014

In reply to: [tz] [PATCH] More spelling and accent fixes. Paul Eggert eggert at CS.UCLA.EDU Fri Jun 27 23:06:47 UTC 2014 A small problem regarding the transition to UTF-8. Let me refer to a copy of some text from the diff, sent through the mailing list: @@ -383,7 +383,7 @@ Zone Asia/Chongqing 7:06:20 - LMT 1928 # or Chungking # Wusu, Qiemo, Xinyan, Wulanwusu, Jinghe, Yumin, Tacheng, Tuoli, Emin, # Shihezi, Changji, Yanqi, Heshuo, Tuokexun, Tulufan, Shanshan, Hami, # Fukang, Kuitun, Kumukuli, Miquan, Qitai, and Turfan. -Zone Asia/Urumqi 5:50:20 - LMT 1928 # ÃœrÃ¼mqi or Urumchi +Zone Asia/Urumqi 5:50:20 - LMT 1928 # ÃœrÃ¼mqi or ÃœrÃ¼mchi The correct spelling of the Asian city at hand is Ürümchi, with two u-diaeresis. The github asia file has the correct spelling and the correct encoding. The diff file however gets mangled by some publishing process. Hence, the diff published through the mailing list is rather useless. I have a lot of text encoding conversion filters, but noone is able to decode the mangled "ÃœrÃ¼mqi". It looks to me like a doubly UTF-8 encoded piece of text. Perhaps something to look into? Oscar van Vlijmen

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[PATCH 0/2] Follow Australian common usage and update CST/CST to CST/CDT and EST/EST to EST/EDT etc [SEC=UNCLASSIFIED]
by Timothy Arceri July 1, 2014

July 1, 2014

After reading the 'Procedures for Maintaining the Time Zone Database' document and the comments in the Australasia data file about how the Australian abbreviations were decided I've come to a better understanding of the current situation and the tz database maintainers position on using common usage for abbreviations. I've come to the conclusion that while I still think 'A' should be added to the front of the Australian abbreviations, we are yet to give conclusive evidence that this is in fact what is the most common usage in Australia (even though as an Australian I know it is). Despite the that fact that these abbreviations are defined on multiple government websites the TZ database maintainers have clearly laid out the terms for changes (no matter how much I disagree, and how difficult proving common usage is) However there *is* one abbreviations common usage that we have proven using the similar methods used by the maintainers for surveying usage. Which is backed up by each government website regardless of the inconsistent use of a leading 'A'. The 'Procedures for Maintaining the Time Zone Database' document clearly states we should first attempt to resolve any concern with the TZ Coordinator, but so far Paul has remained silent on this issue choosing rather to respond only in regards to the use of the leading 'A'. I'm appealing to Paul to please respond either accepting this patch or voicing any remaining concerns. For those that missed our results here they are: * Google search results, do Australians more often use "EDT" or "EST"? 875,000 "Eastern Standard Time (EST)" site:.au 655,000 "Eastern Standard Time (AEST)" site:.au 6 "Eastern Summer Time (EST)" site:.au 64 "Eastern Summer Time (AEST)" site:.au 30,500 "Eastern Daylight Time (EDT)" site:.au 180,000 "Eastern Daylight Time (AEDT)" site:.au 357,000 "Central Standard Time (CST)" site:.au 316 "Central Standard Time (ACST)" site:.au 4 "Central Summer Time (CST)" site:.au 0 "Central Summer Time (ACST)" site:.au 19,600 "Central Daylight Time (CDT)" site:.au 157 "Central Daylight Time (ACDT)" site:.au Here we are only looking at cases where the time zone abbreviation has been defined as anything else is misleading. These results show that the abbreviation for Daylight time EDT/AEDT/CDT/ACDT is overwhelmingly greater than the usage of the abbreviation for Summer time EST/AEST/CST/ACST. The reason for the current situation is documented in the Australasia data file: >From John Mackin (1991-03-06): "We in Australia have _never_ referred to DST as `daylight' time. It is called `summer' time. Now by a happy coincidence, `summer' and `standard' happen to start with the same letter; hence, the abbreviation does _not_ change..." There is no survey of common use, just one man's assertion that this is what the abbreviation should be no matter how ridiculous it is to use the same abbreviation for two different phrases within the same time zone. Aside from the many other problems I have with his statements (such as not a single reference to show the use of the abbreviations) there is one thing that I would like to point out. These three letters are used as identifiers so that they can be associated with a phrase by human (its already been stated they are useless computationally), and in Johns own words they are abbreviations or as a trusty dictionary will show 'shortening something by omitting parts of it'. It does not matter what letter the word starts with its not an acronym it's an abbreviation. Take the this Australian island for example 'C'o'c'os Islands 'T'ime (CCT). Using the same abbreviations for different phrase's while probably done with good intentions has been a confusing mistake all along with no references of its common use. Having said all this the survey results speak for themselves. Please fix this issue. The following two emails contain patches for the Australasia and Antarctica data files. As well as the abbreviations I have updated the comments section for Australia to include the justification for this update and also updated a couple of out-dated links. Thanks for your time, Timothy Arceri

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[PATCH] A few more fixes related to AEST/AEDT etc. (Thanks to Tim Parenti.)
by Paul Eggert June 30, 2014

June 30, 2014

* Theory: Use CST instead of EST in the example, so that it matches the current database. * antarctica (Antarctica/Casey): AWST, not WST. * asia (Asia/Jayapura): ACST, not CST. * australasia: Prepend "[A]" to "EST" in quote about EST. --- Theory | 6 +++--- antarctica | 8 ++++---- asia | 4 ++-- australasia | 2 +- 4 files changed, 10 insertions(+), 10 deletions(-) diff --git a/Theory b/Theory index a956d85..05a9f65 100644 --- a/Theory +++ b/Theory @@ -542,10 +542,10 @@ in decreasing order of importance: in some sense, asleep. Application writers should note that these abbreviations are ambiguous -in practice: e.g. 'EST' has a different meaning in Australia than +in practice: e.g. 'CST' has a different meaning in China than it does in the United States. In new applications, it's often better -to use numeric UT offsets like '-0500' instead of time zone -abbreviations like 'EST'; this avoids the ambiguity. +to use numeric UT offsets like '-0600' instead of time zone +abbreviations like 'CST'; this avoids the ambiguity. ----- Calendrical issues ----- diff --git a/antarctica b/antarctica index 26a6219..101e9c7 100644 --- a/antarctica +++ b/antarctica @@ -103,13 +103,13 @@ Rule ChileAQ 2012 max - Sep Sun>=2 4:00u 1:00 S # Zone NAME GMTOFF RULES FORMAT [UNTIL] Zone Antarctica/Casey 0 - zzz 1969 - 8:00 - WST 2009 Oct 18 2:00 - # Western (Aus) Standard Time + 8:00 - AWST 2009 Oct 18 2:00 + # western Australia time 11:00 - CAST 2010 Mar 5 2:00 # Casey Time - 8:00 - WST 2011 Oct 28 2:00 + 8:00 - AWST 2011 Oct 28 2:00 11:00 - CAST 2012 Feb 21 17:00u - 8:00 - WST + 8:00 - AWST Zone Antarctica/Davis 0 - zzz 1957 Jan 13 7:00 - DAVT 1964 Nov # Davis Time 0 - zzz 1969 Feb diff --git a/asia b/asia index 54a8dc7..3f7d019 100644 --- a/asia +++ b/asia @@ -50,7 +50,7 @@ # 9:00 WIT east Indonesia (Waktu Indonesia Timur) # 9:00 JST JDT Japan # 9:00 KST KDT Korea -# 9:30 CST (Australian) Central Standard Time +# 9:30 ACST Australian Central Standard Time # # See the 'europe' file for Russia and Turkey in Asia. @@ -800,7 +800,7 @@ Zone Asia/Makassar 7:57:36 - LMT 1920 # Maluku Islands, West Papua, Papua Zone Asia/Jayapura 9:22:48 - LMT 1932 Nov 9:00 - WIT 1944 Sep 1 - 9:30 - CST 1964 + 9:30 - ACST 1964 9:00 - WIT # Iran diff --git a/australasia b/australasia index 69f61f1..1fd7cb1 100644 --- a/australasia +++ b/australasia @@ -232,7 +232,7 @@ Zone Australia/Lord_Howe 10:36:20 - LMT 1895 Feb # # From Arthur David Olson (2013-05-23): # The 1919 transition is overspecified below so pre-2013 zics -# will produce a binary file with an EST-type as the first 32-bit type; +# will produce a binary file with an [A]EST-type as the first 32-bit type; # this is required for correct handling of times before 1916 by # pre-2013 versions of localtime. Zone Antarctica/Macquarie 0 - zzz 1899 Nov -- 1.9.1

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