January 2017 - tz - lists.iana.org

proposed time zone package changes (Samoa, Factory, et al.)
by Arthur David Olson 28 Aug '19

28 Aug '19

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

Alberta Tory leadership candidate petitions to drop DST and move to CT
by Brian Inglis 19 Sep '17

19 Sep '17

On the final day of the fall sitting on Tuesday, Alberta Progressive Conservative leadership candidate, Vermilion-Lloydminster MLA Richard Starke presented a petition to the legislature calling for repeal of the Daylight Saving Time Act and a move to Central Time (from Mountain Time), to be decided by a referendum. The stories linked below are all from the same news org and under the same byline. The latter two have a vote button at the bottom to poll readers' opinions, each currently running about 80/20 in favour of dropping DST, and/or possibly also of switching to permanent CT, depending on whether the voters read the question or just clicked. http://calgaryherald.com/news/politics/pc-leadership-candidate-starke-calls… http://www.edmontonjournal.com/news/politics/leadership+candidate+starke+ca… http://www.calgarysun.com/2016/12/14/to-keep-or-ditch-daylight-saving-time-… http://www.edmontonsun.com/2016/12/14/to-keep-or-ditch-daylight-saving-time… -- Take care. Thanks, Brian Inglis, Calgary, Alberta, Canada

6 14

Syntax highlighting for Sublime Text
by Gilmore Davidson 16 Aug '17

16 Aug '17

Hi, I’ve created some tzdata syntax highlighting rules for the Sublime Text editor: https://packagecontrol.io/packages/zoneinfo <https://packagecontrol.io/packages/zoneinfo> I have no idea if anyone other than me uses that particular text editor for looking at tzdata files. But I thought I’d mention it just in case it’s useful to someone. Cheers, Gil

3 3

Re: [tz] question about mktime_tzname()
by Kees Dekker 14 Mar '17

14 Mar '17

Hi, Can anyone help me? In short, I set TZ to EST5EDT,M4.1.0/02:00,M10.5.0/02:00, which means daylight saving for EST (=GMT-5 or GMT-4 if DST is active), with switching DST at first Sunday of April and move to standard time at the last Sunday of October. The input to mktime is (See also attached source code) 1-1-1970, 19:00h (tm_min=1140 = 1140/60 = 19h) local EST time and tm_isdst set to -1. Because of this value, the tz code should figure out that 1-1-1970 is not in DST so the time difference with GMT/UTC is 5 hours. I would exect then mktime() to return 0. This is true if I use the system functions, but mktime() returns -3600 when using the tz library. The output of running the test case with system libraries is: ./tztestcase enter mktime with: 1970/Jan/00 00:1140:00, week day: -858993460, year day: -858993460, dst: -1 the return value of mktime is: 0 normalized times: 1969/Dec/31 19:00:00, week day: Wed, year day: 364, dst: 0 The output of the test case with the tz lib is: ./tztestcase2016j enter mktime with: 1970/Jan/00 00:1140:00, week day: -858993460, year day: -858993460, dst: -1 the return value of mktime is: -3600 normalized times: 1969/Dec/31 19:00:00, week day: Wed, year day: 364, dst: 1 Please correct me if I'm wrong. Is this a bug in the tz code? Please note the differences. From: Kees Dekker Sent: Thursday, January 05, 2017 15:03 To: 'tz(a)iana.org' <tz(a)iana.org> Subject: question about mktime_tzname() Hi, I'm running into a potential bug. Please also see the attached C-source file for a reproduction. Reproduction steps: 1. Build tz code, in such way that a libtz.a exists 2. Compile attached source with (e.g. on Linux): gcc -g -o tztestcase2016j tztestcase.c -L <tzlibdir> -ltz 3. Checking the same test case source code with a system library (instead of IANA libtz.a) can be achieved by omitting -L and -l flags in previous command (see #2). It does not make much sense which version of tzcode is used, I tried 2013i and 2016j and both show the same behavior. The mktime() code returns -3600, while I expect 0. Because the TZ zone is explicitly specified, EST5EDT is GMT-5. So the provided time stamp (31-Jan-1969, 19:00) is exactly the same as UTC value 0 (1-Jan-1970, 00:00 GMT). Both Linux and Windows with system libraries return 0 in this specific case (I used these for reference). The remainder of this email is based on the tzcode2016j source code (e.g. for used line numbers). The provided TZ value is parsed in tzparse() and results in sp->ttis[0] set as DST value, and sp->ttis[1] as standard time value. This is at least contrary to in the else part of the if (*name == ',' || *name == ';') block (there DST is saved in sp->ttis[1]). Just grep on init_ttinfo() calls in localtime.c. However, in localsub(), around line 1428, the i becomes sp->defaulttype (which is zero), i.e. points to the DST value of sp->ttis[], which is assigned to ttisp. As result, because t is below sp->ats[0], DST takes into effect, which is incorrect, as everything after the last Sunday in October and before the first Sunday in April (see attachment, TZ="EST5EDT,M4.1.0/02:00,M10.5.0/02:00") is assumed to be standard time. I'm not sure whether I draw the right conclusion, but because the incorrect assumption of using DST, mktime() returns -3600 (on hour off) instead of the expected 0. Is this conclusion correct? I'm not sure how to fix it. When changing the call to init_ttinfo() and effectively swapping DST and standard time (also for symmetry with the else part) in sp-ttis[] (0 to 1 and 1 to 0) + keeping sp->defaulttype = 0 solved this problem, but introduces other conversion errors around DSTchanges (I don't have yet an reproduction, but can make one if needed). The sp->default type is used (in localsub ()) when if (sp->timecnt == 0 || t < sp->ats[0]). The other approach is to assign sp->defaulttype = 1 when the init_ttinfo() calls are not swapped. Anyhow, there is a tight relationship between the value of sp->defaulttype and the order in which DST/standard times are written in sp->ttis[]. If the previous idea is incorrect (and I guess it is), additional code may be needed in time2sub() if yourtm.tm_isdst == -1. In that case, the provided data in yourtm should be checked whether DST is (or is not) into effect. The found mytm struct should match. Otherwise a DST correction is needed (one-hour shift). The current code mistakenly uses DST, and that is why (if I understand all well) mktime() now returns -3600. If I was not able to explain the issue correctly, please let me know. I'm not sure to understand what's going wrong now, but may be, the provided attachment will help in giving better understanding. Because the provided date is near 1970, quite few steps are needed to see what's happing in localtime.c. Regards, Kees Dekker PS. This email has been sent assuming that attachments will not get lost. Otherwise, just copy paste the code below and save to e.g. tztestcase.c. #ifdef _WIN32 #define _CRT_SECURE_NO_WARNINGS #endif #include <time.h> #include <stdio.h> #include <stdlib.h> int main(void) { int ret = 0; const char *months[] = { "Jan", "Feb", "Mar", "April", "May", "June", "July", "Aug", "Sep", "Oct", "Nov", "Dec" }; const char *days[] = { "Sun", "Mon", "Tue", "Wed", "Tur", "Fri", "Sat" }; /* DST switch in April in first Sunday and October, last Sunday */ putenv("TZ=EST5EDT,M4.1.0/02:00,M10.5.0/02:00"); /* January, 1970, invalid input for tm_mday (0 instead 1..31) */ /* non-normalized input for minutes: 1140/60 = 19, so 19:00 EST5EDT time, which is 5 hours before GMT, and should result in t == 0 below */ /* let system figure out whether DST is effect */ struct tm tmp = { 0, 1140, 0, 0, 0, 70, -858993460, -858993460, -1}; printf("enter mktime with: %04d/%s/%02d %02d:%02d:%02d, week day: %d, year day: %d, dst: %d\n", tmp.tm_year + 1900, months[tmp.tm_mon], tmp.tm_mday, tmp.tm_hour, tmp.tm_min, tmp.tm_sec, tmp.tm_wday, tmp.tm_yday, tmp.tm_isdst); time_t t = mktime(&tmp); /* expect: t == 0, DST is off, time is exactly at the boundary of lowest possible UTC value */ printf("the return value of mktime is: %lld\n", (long long)t); printf("normalized times: %04d/%s/%02d %02d:%02d:%02d, week day: %s, year day: %d, dst: %d\n", tmp.tm_year + 1900, months[tmp.tm_mon], tmp.tm_mday, tmp.tm_hour, tmp.tm_min, tmp.tm_sec, days[tmp.tm_wday], tmp.tm_yday, tmp.tm_isdst); if (t >= 0) { printf("tz=%s, %s\n", tzname[0], tzname[1]); } return 0; }

5 26

Re: [tz] Version in zoneinfo files?
by Guy Harris 10 Feb '17

10 Feb '17

On Oct 25, 2015, at 10:55 AM, Paul G <paul(a)ganssle.io> wrote: > I'm not suggesting that it be impossible to create a weird result when asking for the version, just that there's a standard place for the version to go, and preferably the standard default gives you something that you expected. I.e., something that works most of the time is sufficient? So what exactly is the intended use of this version field? > As it is now, you're virtually guaranteed to have a lot of incompatibility because there's nothing you can point to that says, "This is the canonical way to store version information about zoneinfo files", and no standard has emerged on how to do this as is. > > On 10/25/2015 01:51 PM, Guy Harris wrote: >> >> On Oct 25, 2015, at 10:37 AM, Paul G <paul(a)ganssle.io> wrote: >> >>> On 10/25/2015 01:35 PM, Guy Harris wrote: >>> >>>> So where would zic get the version information to put into the binary files? >>> >>> My understanding is that it's the VERSION= line of the Makefile in the tzdata tarballs. >> >> I.e., you're proposing that the value of the VERSION value in the Makefile be passed as an argument to zic, and zic would put the value of that argument into a field in the files? >> >> So, if the goal is to provide a "reliable way to get the version information in a cross-platform way", what would ensure that this field be set properly, for some value of "properly", everywhere that binary tzdata files are generated? >> >> I.e., what is to guarantee that >> >> 1) nobody downstream change VERSION if they aren't changing the zic files from what's distributed >> >> and >> >> 2) people change it "properly" if the files don't correspond to a particular version of files that were distributed (e.g., if some downstream supplier takes 2015q and adds some changes mentioned on the list to it before 2015r comes out with those changes plus other changes, they should call the resulting files something other than "2015q" or "2015r")? >> >

20 55

Magallanes region from Chile will keep DST all year round
by Juan Correa 30 Jan '17

30 Jan '17

There is no official decree published yet, but it has been reported by official Chilean government Twitter accounts that Magallanes región ( https://en.wikipedia.org/wiki/Magallanes_Region) will keep DST (UTC -3) all year round Sources: - https://twitter.com/presidencia_cl/status/805398903604576256 (from Press Office of the Presidency of Chile, "President Michelle Bachelet signs the decree that establishes a single timezone for Magallanes región") - https://twitter.com/AndresReboll/status/805398964690386944 (from Minister of Energy, "after a participative (sic) process and thoughtful investigation, decided to establish a single timezone (*summer*) for Magallanes) - http://www.soychile.cl/Santiago/Sociedad/2016/12/04/433428/Bachelet-firmo-e… As a reminder, Chile has (since 2016) DST from August to May following year The biggest city in the region is Punta Arenas, with over 123 thousand inhabitants. The whole population for Magallanes region is 164.661 people As soon as the decree gets published, I'll share it here -- Juan Correa Poblete PS Labs (http://www.pslabs.cl)

10 25

[PROPOSED] Remove many invented abbreviations in 'asia'
by Paul Eggert 20 Jan '17

20 Jan '17

* NEWS: Document this. List areas changed rather than each individual zone, as there are so many. * asia (Asia/Kabul, Asia/Dhaka, Asia/Thimphu, Indian/Chagos) (Asia/Brunei, Asia/Yangon, Asia/Urumqi, Asia/Taipei, Asia/Dili) (Asia/Kolkata, Asia/Jakarta, Asia/Pontianak, Asia/Makassar) (Asia/Jayapura, Asia/Tehran, Asia/Baghdad, Asia/Kuala_Lumpur) (Asia/Kuching, Indian/Maldives, Asia/Hovd, Asia/Ulaanbaatar) (Asia/Choibalsan, Asia/Kathmandu, Asia/Karachi, Asia/Manila, Asia/Qatar) (Asia/Riyadh, Asia/Singapore, Asia/Bangkok, Asia/Dubai) (Asia/Ho_Chi_Minh): Use numeric rather than invented abbreviations. (Asia/Taipei, Macau, Asia/Macau, Asia/Tokyo, Asia/Seoul, Asia/Pyongyang): Use common (e.g., "JST") rather than invented (e.g., "JCST") abbreviations. (Asia/Colombo): Remove unused abbreviations. --- NEWS | 39 ++++------ asia | 258 +++++++++++++++++++++++++++++++------------------------------------ 2 files changed, 136 insertions(+), 161 deletions(-) diff --git a/NEWS b/NEWS index 79620eb..8276cc7 100644 --- a/NEWS +++ b/NEWS @@ -32,36 +32,27 @@ Unreleased, experimental changes Switch to numeric time zone abbreviations for South America, as part of the ongoing project of removing invented abbreviations. This avoids the need to invent an abbreviation for the new Chilean - new zone. This change affects America/Araguaina, - America/Argentina/Buenos_Aires, America/Argentina/Catamarca, - America/Argentina/Cordoba, America/Argentina/Jujuy, - America/Argentina/La_Rioja, America/Argentina/Mendoza, - America/Argentina/Rio_Gallegos, America/Argentina/Salta, - America/Argentina/San_Juan, America/Argentina/San_Luis, - America/Argentina/Tucuman, America/Argentina/Ushuaia, - America/Asuncion, America/Bahia, America/Belem, America/Boa_Vista, - America/Bogota, America/Campo_Grande, America/Caracas, - America/Cayenne, America/Cuiaba, America/Curacao, - America/Eirunepe, America/Fortaleza, America/Guayaquil, - America/Guyana, America/La_Paz, America/Lima, America/Maceio, - America/Manaus, America/Montevideo, America/Noronha, - America/Paramaribo, America/Porto_Velho, America/Recife, - America/Rio_Branco, America/Santarem, America/Santiago, - America/Sao_Paulo, Antarctica/Palmer, Atlantic/South_Georgia, - Atlantic/Stanley, Pacific/Easter, and Pacific/Galapagos. - - Similarly, switch from invented to numeric time zone abbreviations - for Greenland, the Azores, and St Pierre and Miquelon; for - half-hour DST in Belize before 1944 and in the Dominican Republic - before 1975; and for Canary Islands before 1946, for Madeira - before 1967, for Iceland before 1969, for the Netherlands in - 1937-9, and for Zaporozhye in 1880-1924. + new zone. Similarly, switch from invented to numeric time zone + abbreviations for Afghanistan, the Azores, Bangladesh, Bhutan, the + British Indian Ocean Territory, Brunei, Dubai, East Timor, + Greenland, Indochina, Iran, Iraq, Malaysia, the Maldives, + Mongolia, Myanmar, Nepal, the Philippines, Qatar, St Pierre and + Miquelon, Saudi Arabia, Singapore, and Xinjiang; for half-hour DST + in Belize before 1944 and in the Dominican Republic before 1975; + and for Canary Islands before 1946, for Madeira before 1967, for + Iceland before 1969, for Indian Summer Time before 1942, for + Indonesia before around 1964, for the Netherlands in 1937-9, for + Pakistan before 1971, and for Zaporozhye in 1880-1924. For Alaska time from 1900 through 1967, instead of "CAT" use the abbreviation "AST", the abbreviation commonly used at the time (Atlantic Standard Time had not been standardized yet). Use "AWT" and "APT" instead of the invented abbreviations "CAWT" and "CAPT". + Use "CST" and "CDT" instead of invented abbreviations for Macau + before 1999 and Taiwan before 1938, and use "JST" instead of the + invented abbreviation "JCST" for Japan and Korea before 1938. + Changes to code zic no longer mishandles some transitions in January 2038 when it diff --git a/asia b/asia index 6129614..26b6a5b 100644 --- a/asia +++ b/asia @@ -6,15 +6,15 @@ # tz(a)iana.org for general use in the future). For more, please see # the file CONTRIBUTING in the tz distribution. -# From Paul Eggert (2015-08-08): +# From Paul Eggert (2017-01-13): # # Unless otherwise specified, the source for data through 1990 is: # Thomas G. Shanks and Rique Pottenger, The International Atlas (6th edition), # San Diego: ACS Publications, Inc. (2003). # Unfortunately this book contains many errors and cites no sources. # -# Gwillim Law writes that a good source -# for recent time zone data is the International Air Transport +# Many years ago Gwillim Law wrote that a good source +# for time zone data was the International Air Transport # Association's Standard Schedules Information Manual (IATA SSIM), # published semiannually. Law sent in several helpful summaries # of the IATA's data after 1990. Except where otherwise noted, @@ -35,29 +35,24 @@ # A reliable and entertaining source about time zones is # Derek Howse, Greenwich time and longitude, Philip Wilson Publishers (1997). # -# I invented the abbreviations marked '*' in the following table; -# the rest are from earlier versions of this file, or from other sources. -# Corrections are welcome! +# The following alphabetic abbreviations appear in these tables: # std dst # LMT Local Mean Time # 2:00 EET EEST Eastern European Time # 2:00 IST IDT Israel -# 3:00 AST ADT Arabia* -# 3:30 IRST IRDT Iran* -# 4:00 GST Gulf* # 5:30 IST India -# 7:00 ICT Indochina, most times and locations* # 7:00 WIB west Indonesia (Waktu Indonesia Barat) # 8:00 WITA central Indonesia (Waktu Indonesia Tengah) # 8:00 CST China -# 8:00 IDT Indochina, 1943-45, 1947-55, 1960-75 (some locations)* -# 8:00 JWST Western Standard Time (Japan, 1896/1937)* -# 8:30 KST KDT Korea when at +0830* -# 9:00 JCST Central Standard Time (Japan, 1896/1937) +# 8:30 KST KDT Korea when at +0830 # 9:00 WIT east Indonesia (Waktu Indonesia Timur) # 9:00 JST JDT Japan # 9:00 KST KDT Korea when at +09 # 9:30 ACST Australian Central Standard Time +# Otherwise, these tables typically use numeric abbreviations like +03 +# and +0330 for integer hour and minute UTC offsets. Although earlier +# editions invented alphabetic time zone abbreviations for every +# offset, this did not reflect common practice. # # See the 'europe' file for Russia and Turkey in Asia. @@ -65,7 +60,7 @@ # Incorporates data for Singapore from Robert Elz' asia 1.1, as well as # additional information from Tom Yap, Sun Microsystems Intercontinental # Technical Support (including a page from the Official Airline Guide - -# Worldwide Edition). The names for time zones are guesses. +# Worldwide Edition). ############################################################################### @@ -86,8 +81,8 @@ Rule RussiaAsia 1996 2011 - Oct lastSun 2:00s 0 - # Afghanistan # Zone NAME GMTOFF RULES FORMAT [UNTIL] Zone Asia/Kabul 4:36:48 - LMT 1890 - 4:00 - AFT 1945 - 4:30 - AFT + 4:00 - +04 1945 + 4:30 - +0430 # Armenia # From Paul Eggert (2006-03-22): @@ -230,18 +225,17 @@ Rule Dhaka 2009 only - Dec 31 24:00 0 - # Zone NAME GMTOFF RULES FORMAT [UNTIL] Zone Asia/Dhaka 6:01:40 - LMT 1890 5:53:20 - HMT 1941 Oct # Howrah Mean Time? - 6:30 - BURT 1942 May 15 # Burma Time - 5:30 - IST 1942 Sep - 6:30 - BURT 1951 Sep 30 - 6:00 - DACT 1971 Mar 26 # Dacca Time - 6:00 - BDT 2009 - 6:00 Dhaka BD%sT + 6:30 - +0630 1942 May 15 + 5:30 - +0530 1942 Sep + 6:30 - +0630 1951 Sep 30 + 6:00 - +06 2009 + 6:00 Dhaka +06/+07 # Bhutan # Zone NAME GMTOFF RULES FORMAT [UNTIL] Zone Asia/Thimphu 5:58:36 - LMT 1947 Aug 15 # or Thimbu - 5:30 - IST 1987 Oct - 6:00 - BTT # Bhutan Time + 5:30 - +0530 1987 Oct + 6:00 - +06 # British Indian Ocean Territory # Whitman and the 1995 CIA time zone map say 5:00, but the @@ -251,14 +245,14 @@ Zone Asia/Thimphu 5:58:36 - LMT 1947 Aug 15 # or Thimbu # then contained the Chagos Archipelago). # Zone NAME GMTOFF RULES FORMAT [UNTIL] Zone Indian/Chagos 4:49:40 - LMT 1907 - 5:00 - IOT 1996 # BIOT Time - 6:00 - IOT + 5:00 - +05 1996 + 6:00 - +06 # Brunei # Zone NAME GMTOFF RULES FORMAT [UNTIL] Zone Asia/Brunei 7:39:40 - LMT 1926 Mar # Bandar Seri Begawan - 7:30 - BNT 1933 - 8:00 - BNT + 7:30 - +0730 1933 + 8:00 - +08 # Burma / Myanmar @@ -267,9 +261,9 @@ Zone Asia/Brunei 7:39:40 - LMT 1926 Mar # Bandar Seri Begawan # Zone NAME GMTOFF RULES FORMAT [UNTIL] Zone Asia/Yangon 6:24:40 - LMT 1880 # or Rangoon 6:24:40 - RMT 1920 # Rangoon Mean Time? - 6:30 - BURT 1942 May # Burma Time - 9:00 - JST 1945 May 3 - 6:30 - MMT # Myanmar Time + 6:30 - +0630 1942 May + 9:00 - +09 1945 May 3 + 6:30 - +0630 # Cambodia # See Asia/Bangkok. @@ -521,7 +515,7 @@ Zone Asia/Shanghai 8:05:43 - LMT 1901 # Xinjiang time, used by many in western China; represented by Ürümqi / Ürümchi # / Wulumuqi. (Please use Asia/Shanghai if you prefer Beijing time.) Zone Asia/Urumqi 5:50:20 - LMT 1928 - 6:00 - XJT + 6:00 - +06 # Hong Kong (Xianggang) @@ -740,30 +734,29 @@ Rule Taiwan 1979 only - Oct 1 0:00 0 S # Zone NAME GMTOFF RULES FORMAT [UNTIL] # Taipei or Taibei or T'ai-pei Zone Asia/Taipei 8:06:00 - LMT 1896 Jan 1 - 8:00 - JWST 1937 Oct 1 + 8:00 - CST 1937 Oct 1 9:00 - JST 1945 Sep 21 1:00 8:00 Taiwan C%sT # Macau (Macao, Aomen) # Rule NAME FROM TO TYPE IN ON AT SAVE LETTER/S -Rule Macau 1961 1962 - Mar Sun>=16 3:30 1:00 S -Rule Macau 1961 1964 - Nov Sun>=1 3:30 0 - -Rule Macau 1963 only - Mar Sun>=16 0:00 1:00 S -Rule Macau 1964 only - Mar Sun>=16 3:30 1:00 S -Rule Macau 1965 only - Mar Sun>=16 0:00 1:00 S -Rule Macau 1965 only - Oct 31 0:00 0 - -Rule Macau 1966 1971 - Apr Sun>=16 3:30 1:00 S -Rule Macau 1966 1971 - Oct Sun>=16 3:30 0 - -Rule Macau 1972 1974 - Apr Sun>=15 0:00 1:00 S -Rule Macau 1972 1973 - Oct Sun>=15 0:00 0 - -Rule Macau 1974 1977 - Oct Sun>=15 3:30 0 - -Rule Macau 1975 1977 - Apr Sun>=15 3:30 1:00 S -Rule Macau 1978 1980 - Apr Sun>=15 0:00 1:00 S -Rule Macau 1978 1980 - Oct Sun>=15 0:00 0 - +Rule Macau 1961 1962 - Mar Sun>=16 3:30 1:00 D +Rule Macau 1961 1964 - Nov Sun>=1 3:30 0 S +Rule Macau 1963 only - Mar Sun>=16 0:00 1:00 D +Rule Macau 1964 only - Mar Sun>=16 3:30 1:00 D +Rule Macau 1965 only - Mar Sun>=16 0:00 1:00 D +Rule Macau 1965 only - Oct 31 0:00 0 S +Rule Macau 1966 1971 - Apr Sun>=16 3:30 1:00 D +Rule Macau 1966 1971 - Oct Sun>=16 3:30 0 S +Rule Macau 1972 1974 - Apr Sun>=15 0:00 1:00 D +Rule Macau 1972 1973 - Oct Sun>=15 0:00 0 S +Rule Macau 1974 1977 - Oct Sun>=15 3:30 0 S +Rule Macau 1975 1977 - Apr Sun>=15 3:30 1:00 D +Rule Macau 1978 1980 - Apr Sun>=15 0:00 1:00 D +Rule Macau 1978 1980 - Oct Sun>=15 0:00 0 S # Zone NAME GMTOFF RULES FORMAT [UNTIL] Zone Asia/Macau 7:34:20 - LMT 1912 Jan 1 - 8:00 Macau MO%sT 1999 Dec 20 # return to China - 8:00 PRC C%sT + 8:00 Macau C%sT ############################################################################### @@ -879,11 +872,10 @@ Zone Asia/Tbilisi 2:59:11 - LMT 1880 # Zone NAME GMTOFF RULES FORMAT [UNTIL] Zone Asia/Dili 8:22:20 - LMT 1912 Jan 1 - 8:00 - TLT 1942 Feb 21 23:00 # E Timor Time - 9:00 - JST 1945 Sep 23 - 9:00 - TLT 1976 May 3 - 8:00 - WITA 2000 Sep 17 0:00 - 9:00 - TLT + 8:00 - +08 1942 Feb 21 23:00 + 9:00 - +09 1976 May 3 + 8:00 - +08 2000 Sep 17 0:00 + 9:00 - +09 # India @@ -898,9 +890,9 @@ Zone Asia/Dili 8:22:20 - LMT 1912 Jan 1 # Zone NAME GMTOFF RULES FORMAT [UNTIL] Zone Asia/Kolkata 5:53:28 - LMT 1880 # Kolkata 5:53:20 - HMT 1941 Oct # Howrah Mean Time? - 6:30 - BURT 1942 May 15 # Burma Time + 6:30 - +0630 1942 May 15 5:30 - IST 1942 Sep - 5:30 1:00 IST 1945 Oct 15 + 5:30 1:00 +0630 1945 Oct 15 5:30 - IST # The following are like Asia/Kolkata: # Andaman Is @@ -951,33 +943,33 @@ Zone Asia/Jakarta 7:07:12 - LMT 1867 Aug 10 # Shanks & Pottenger say the next transition was at 1924 Jan 1 0:13, # but this must be a typo. 7:07:12 - BMT 1923 Dec 31 23:47:12 # Batavia - 7:20 - JAVT 1932 Nov # Java Time - 7:30 - WIB 1942 Mar 23 - 9:00 - JST 1945 Sep 23 - 7:30 - WIB 1948 May - 8:00 - WIB 1950 May - 7:30 - WIB 1964 + 7:20 - +0720 1932 Nov + 7:30 - +0730 1942 Mar 23 + 9:00 - +09 1945 Sep 23 + 7:30 - +0730 1948 May + 8:00 - +08 1950 May + 7:30 - +0730 1964 7:00 - WIB # west and central Borneo Zone Asia/Pontianak 7:17:20 - LMT 1908 May 7:17:20 - PMT 1932 Nov # Pontianak MT - 7:30 - WIB 1942 Jan 29 - 9:00 - JST 1945 Sep 23 - 7:30 - WIB 1948 May - 8:00 - WIB 1950 May - 7:30 - WIB 1964 + 7:30 - +0730 1942 Jan 29 + 9:00 - +09 1945 Sep 23 + 7:30 - +0730 1948 May + 8:00 - +08 1950 May + 7:30 - +0730 1964 8:00 - WITA 1988 Jan 1 7:00 - WIB # Sulawesi, Lesser Sundas, east and south Borneo Zone Asia/Makassar 7:57:36 - LMT 1920 7:57:36 - MMT 1932 Nov # Macassar MT - 8:00 - WITA 1942 Feb 9 - 9:00 - JST 1945 Sep 23 + 8:00 - +08 1942 Feb 9 + 9:00 - +09 1945 Sep 23 8:00 - WITA # Maluku Islands, West Papua, Papua Zone Asia/Jayapura 9:22:48 - LMT 1932 Nov - 9:00 - WIT 1944 Sep 1 - 9:30 - ACST 1964 + 9:00 - +09 1944 Sep 1 + 9:30 - +0930 1964 9:00 - WIT # Iran @@ -1009,8 +1001,6 @@ Zone Asia/Jayapura 9:22:48 - LMT 1932 Nov # for at least the last 5 years. Before that, for a few years, the # date used was the first Thursday night of Farvardin and the last # Thursday night of Shahrivar, but I can't give exact dates.... -# I have also changed the abbreviations to what is considered correct -# here in Iran, IRST for regular time and IRDT for daylight saving time. # # From Roozbeh Pournader (2005-04-05): # The text of the Iranian law, in effect since 1925, clearly mentions @@ -1117,9 +1107,9 @@ Rule Iran 2036 max - Sep 21 0:00 0 S # Zone NAME GMTOFF RULES FORMAT [UNTIL] Zone Asia/Tehran 3:25:44 - LMT 1916 3:25:44 - TMT 1946 # Tehran Mean Time - 3:30 - IRST 1977 Nov - 4:00 Iran IR%sT 1979 - 3:30 Iran IR%sT + 3:30 - +0330 1977 Nov + 4:00 Iran +04/+05 1979 + 3:30 Iran +0330/+0430 # Iraq @@ -1162,8 +1152,8 @@ Rule Iraq 1991 2007 - Oct 1 3:00s 0 S # Zone NAME GMTOFF RULES FORMAT [UNTIL] Zone Asia/Baghdad 2:57:40 - LMT 1890 2:57:36 - BMT 1918 # Baghdad Mean Time? - 3:00 - AST 1982 May - 3:00 Iraq A%sT + 3:00 - +03 1982 May + 3:00 Iraq +03/+04 ############################################################################### @@ -1462,8 +1452,6 @@ Rule Japan 1950 1951 - May Sun>=1 2:00 1:00 D # Zone NAME GMTOFF RULES FORMAT [UNTIL] Zone Asia/Tokyo 9:18:59 - LMT 1887 Dec 31 15:00u - 9:00 - JST 1896 Jan 1 - 9:00 - JCST 1937 Oct 1 9:00 Japan J%sT # Since 1938, all Japanese possessions have been like Asia/Tokyo. @@ -1940,14 +1928,12 @@ Rule ROK 1987 1988 - Oct Sun>=8 3:00 0 S # Zone NAME GMTOFF RULES FORMAT [UNTIL] Zone Asia/Seoul 8:27:52 - LMT 1908 Apr 1 8:30 - KST 1912 Jan 1 - 9:00 - JCST 1937 Oct 1 9:00 - JST 1945 Sep 8 9:00 - KST 1954 Mar 21 8:30 ROK K%sT 1961 Aug 10 9:00 ROK K%sT Zone Asia/Pyongyang 8:23:00 - LMT 1908 Apr 1 8:30 - KST 1912 Jan 1 - 9:00 - JCST 1937 Oct 1 9:00 - JST 1945 Aug 24 9:00 - KST 2015 Aug 15 00:00 8:30 - KST @@ -2002,30 +1988,29 @@ Rule NBorneo 1935 1941 - Dec 14 0:00 0 - # Zone NAME GMTOFF RULES FORMAT [UNTIL] Zone Asia/Kuala_Lumpur 6:46:46 - LMT 1901 Jan 1 6:55:25 - SMT 1905 Jun 1 # Singapore M.T. - 7:00 - MALT 1933 Jan 1 # Malaya Time - 7:00 0:20 MALST 1936 Jan 1 - 7:20 - MALT 1941 Sep 1 - 7:30 - MALT 1942 Feb 16 - 9:00 - JST 1945 Sep 12 - 7:30 - MALT 1982 Jan 1 - 8:00 - MYT # Malaysia Time + 7:00 - +07 1933 Jan 1 + 7:00 0:20 +0720 1936 Jan 1 + 7:20 - +0720 1941 Sep 1 + 7:30 - +0730 1942 Feb 16 + 9:00 - +09 1945 Sep 12 + 7:30 - +0730 1982 Jan 1 + 8:00 - +08 # Sabah & Sarawak # From Paul Eggert (2014-08-12): # The data entries here are mostly from Shanks & Pottenger, but the 1942, 1945 # and 1982 transition dates are from Mok Ly Yng. # Zone NAME GMTOFF RULES FORMAT [UNTIL] Zone Asia/Kuching 7:21:20 - LMT 1926 Mar - 7:30 - BORT 1933 # Borneo Time - 8:00 NBorneo BOR%sT 1942 Feb 16 - 9:00 - JST 1945 Sep 12 - 8:00 - BORT 1982 Jan 1 - 8:00 - MYT + 7:30 - +0730 1933 + 8:00 NBorneo +08/+0820 1942 Feb 16 + 9:00 - +09 1945 Sep 12 + 8:00 - +08 # Maldives # Zone NAME GMTOFF RULES FORMAT [UNTIL] Zone Indian/Maldives 4:54:00 - LMT 1880 # Male 4:54:00 - MMT 1960 # Male Mean Time - 5:00 - MVT # Maldives Time + 5:00 - +05 # Mongolia @@ -2164,25 +2149,25 @@ Rule Mongol 2015 max - Sep lastSat 0:00 0 - # Zone NAME GMTOFF RULES FORMAT [UNTIL] # Hovd, a.k.a. Chovd, Dund-Us, Dzhargalant, Khovd, Jirgalanta Zone Asia/Hovd 6:06:36 - LMT 1905 Aug - 6:00 - HOVT 1978 # Hovd Time - 7:00 Mongol HOV%sT + 6:00 - +06 1978 + 7:00 Mongol +07/+08 # Ulaanbaatar, a.k.a. Ulan Bataar, Ulan Bator, Urga Zone Asia/Ulaanbaatar 7:07:32 - LMT 1905 Aug - 7:00 - ULAT 1978 # Ulaanbaatar Time - 8:00 Mongol ULA%sT + 7:00 - +07 1978 + 8:00 Mongol +08/+09 # Choibalsan, a.k.a. Bajan Tümen, Bajan Tumen, Chojbalsan, # Choybalsan, Sanbejse, Tchoibalsan Zone Asia/Choibalsan 7:38:00 - LMT 1905 Aug - 7:00 - ULAT 1978 - 8:00 - ULAT 1983 Apr - 9:00 Mongol CHO%sT 2008 Mar 31 # Choibalsan Time - 8:00 Mongol CHO%sT + 7:00 - +07 1978 + 8:00 - +08 1983 Apr + 9:00 Mongol +09/+10 2008 Mar 31 + 8:00 Mongol +08/+09 # Nepal # Zone NAME GMTOFF RULES FORMAT [UNTIL] Zone Asia/Kathmandu 5:41:16 - LMT 1920 - 5:30 - IST 1986 - 5:45 - NPT # Nepal Time + 5:30 - +0530 1986 + 5:45 - +0545 # Oman # See Asia/Dubai. @@ -2331,10 +2316,10 @@ Rule Pakistan 2009 only - Apr 15 0:00 1:00 S # Zone NAME GMTOFF RULES FORMAT [UNTIL] Zone Asia/Karachi 4:28:12 - LMT 1907 - 5:30 - IST 1942 Sep - 5:30 1:00 IST 1945 Oct 15 - 5:30 - IST 1951 Sep 30 - 5:00 - KART 1971 Mar 26 # Karachi Time + 5:30 - +0530 1942 Sep + 5:30 1:00 +0630 1945 Oct 15 + 5:30 - +0530 1951 Sep 30 + 5:00 - +05 1971 Mar 26 5:00 Pakistan PK%sT # Pakistan Time # Palestine @@ -2699,15 +2684,15 @@ Rule Phil 1978 only - Sep 21 0:00 0 - # Zone NAME GMTOFF RULES FORMAT [UNTIL] Zone Asia/Manila -15:56:00 - LMT 1844 Dec 31 8:04:00 - LMT 1899 May 11 - 8:00 Phil PH%sT 1942 May - 9:00 - JST 1944 Nov - 8:00 Phil PH%sT + 8:00 Phil +08/+09 1942 May + 9:00 - +09 1944 Nov + 8:00 Phil +08/+09 # Qatar # Zone NAME GMTOFF RULES FORMAT [UNTIL] Zone Asia/Qatar 3:26:08 - LMT 1920 # Al Dawhah / Doha - 4:00 - GST 1972 Jun - 3:00 - AST + 4:00 - +04 1972 Jun + 3:00 - +03 Link Asia/Qatar Asia/Bahrain # Saudi Arabia @@ -2734,7 +2719,7 @@ Link Asia/Qatar Asia/Bahrain # # Zone NAME GMTOFF RULES FORMAT [UNTIL] Zone Asia/Riyadh 3:06:52 - LMT 1947 Mar 14 - 3:00 - AST + 3:00 - +03 Link Asia/Riyadh Asia/Aden # Yemen Link Asia/Riyadh Asia/Kuwait @@ -2744,14 +2729,13 @@ Link Asia/Riyadh Asia/Kuwait # Zone NAME GMTOFF RULES FORMAT [UNTIL] Zone Asia/Singapore 6:55:25 - LMT 1901 Jan 1 6:55:25 - SMT 1905 Jun 1 # Singapore M.T. - 7:00 - MALT 1933 Jan 1 # Malaya Time - 7:00 0:20 MALST 1936 Jan 1 - 7:20 - MALT 1941 Sep 1 - 7:30 - MALT 1942 Feb 16 - 9:00 - JST 1945 Sep 12 - 7:30 - MALT 1965 Aug 9 # independence - 7:30 - SGT 1982 Jan 1 # Singapore Time - 8:00 - SGT + 7:00 - +07 1933 Jan 1 + 7:00 0:20 +0720 1936 Jan 1 + 7:20 - +0720 1941 Sep 1 + 7:30 - +0730 1942 Feb 16 + 9:00 - +09 1945 Sep 12 + 7:30 - +0730 1982 Jan 1 + 8:00 - +08 # Spratly Is # no information @@ -2810,8 +2794,8 @@ Zone Asia/Singapore 6:55:25 - LMT 1901 Jan 1 Zone Asia/Colombo 5:19:24 - LMT 1880 5:19:32 - MMT 1906 # Moratuwa Mean Time 5:30 - +0530 1942 Jan 5 - 5:30 0:30 +0530/+06 1942 Sep - 5:30 1:00 +0530/+0630 1945 Oct 16 2:00 + 5:30 0:30 +06 1942 Sep + 5:30 1:00 +0630 1945 Oct 16 2:00 5:30 - +0530 1996 May 25 0:00 6:30 - +0630 1996 Oct 26 0:30 6:00 - +06 2006 Apr 15 0:30 @@ -2993,7 +2977,7 @@ Zone Asia/Dushanbe 4:35:12 - LMT 1924 May 2 # Zone NAME GMTOFF RULES FORMAT [UNTIL] Zone Asia/Bangkok 6:42:04 - LMT 1880 6:42:04 - BMT 1920 Apr # Bangkok Mean Time - 7:00 - ICT + 7:00 - +07 Link Asia/Bangkok Asia/Phnom_Penh # Cambodia Link Asia/Bangkok Asia/Vientiane # Laos @@ -3009,7 +2993,7 @@ Zone Asia/Ashgabat 3:53:32 - LMT 1924 May 2 # or Ashkhabad # United Arab Emirates # Zone NAME GMTOFF RULES FORMAT [UNTIL] Zone Asia/Dubai 3:41:12 - LMT 1920 - 4:00 - GST + 4:00 - +04 Link Asia/Dubai Asia/Muscat # Oman # Uzbekistan @@ -3082,15 +3066,15 @@ Zone Asia/Tashkent 4:37:11 - LMT 1924 May 2 # Zone NAME GMTOFF RULES FORMAT [UNTIL] Zone Asia/Ho_Chi_Minh 7:06:40 - LMT 1906 Jul 1 - 7:06:30 - PLMT 1911 May 1 - 7:00 - ICT 1942 Dec 31 23:00 - 8:00 - IDT 1945 Mar 14 23:00 - 9:00 - JST 1945 Sep 2 - 7:00 - ICT 1947 Apr 1 - 8:00 - IDT 1955 Jul 1 - 7:00 - ICT 1959 Dec 31 23:00 - 8:00 - IDT 1975 Jun 13 - 7:00 - ICT + 7:06:30 - PLMT 1911 May 1 # Phù Liễn MT + 7:00 - +07 1942 Dec 31 23:00 + 8:00 - +08 1945 Mar 14 23:00 + 9:00 - +09 1945 Sep 2 + 7:00 - +07 1947 Apr 1 + 8:00 - +08 1955 Jul 1 + 7:00 - +07 1959 Dec 31 23:00 + 8:00 - +08 1975 Jun 13 + 7:00 - +07 # Yemen # See Asia/Riyadh. -- 2.9.3

5 7

[PROPOSED] date +%z now outputs -0000 for uninhabited
by Paul Eggert 15 Jan '17

15 Jan '17

When the time zone has UT offset 0 and the time zone abbreviation begins with "-", the %z spec now expands to -0000 instead of to +0000. This conveys more-useful info, and is what the next version of GNU 'date' is intended to do. * NEWS, newstrftime.3: Document change. * date.1: Document %z. * strftime.c (_fmt): Implement change. --- NEWS | 4 ++++ date.1 | 1 + newstrftime.3 | 12 ++++++++++++ strftime.c | 13 ++++++++++++- 4 files changed, 29 insertions(+), 1 deletion(-) diff --git a/NEWS b/NEWS index 8276cc7..3975295 100644 --- a/NEWS +++ b/NEWS @@ -74,6 +74,10 @@ Unreleased, experimental changes when TZ is set to a POSIX-style string that specifies DST. (Problem reported by Kees Dekker.) + date and strftime now cause %z to generate "-0000" instead of + "+0000" when the UT offset is zero and the time zone abbreviation + begins with "-". + Changes to documentation and commentary tz-link.htm now covers leap smearing, which is popular in clouds. diff --git a/date.1 b/date.1 index 7fd4848..579ab92 100644 --- a/date.1 +++ b/date.1 @@ -90,6 +90,7 @@ to be output in a particular way %X 14:54:40 Time* %y 89 Last two digits of year %Y 1989 Year in full +%z -0500 Numeric time zone %Z EST Time zone abbreviation %+ Wed Mar 8 14:54:40 EST 1989 Default output format* .if t .in -.5i diff --git a/newstrftime.3 b/newstrftime.3 index 9a60ee3..8f1be34 100644 --- a/newstrftime.3 +++ b/newstrftime.3 @@ -50,6 +50,13 @@ strftime \- format date and time .SH DESCRIPTION .ie '\(en'' .ds en \- .el .ds en \(en +.ie '\(lq'' .ds lq \&"\" +.el .ds lq \(lq\" +.ie '\(rq'' .ds rq \&"\" +.el .ds rq \(rq\" +.de q +\\$3\*(lq\\$1\*(rq\\$2 +.. The .I strftime function formats the information from @@ -211,6 +218,11 @@ is replaced by the offset from the Prime Meridian in the format +HHMM or \*-HHMM as appropriate, with positive values representing locations east of Greenwich, or by the empty string if this is not determinable. +The numeric time zone \*-0000 is used when the time is Universal Time +but local time is indeterminate; by convention this is used for +locations while uninhabited, and corresponds to a zero offset when the +time zone abbreviation begins with +.q "\*-" . .TP %% is replaced by a single %. diff --git a/strftime.c b/strftime.c index 984ead5..2bfb6c1 100644 --- a/strftime.c +++ b/strftime.c @@ -500,6 +500,7 @@ label: { long diff; char const * sign; + bool negative; # ifdef TM_GMTOFF diff = t->TM_GMTOFF; @@ -538,7 +539,17 @@ label: continue; # endif # endif - if (diff < 0) { + negative = diff < 0; + if (diff == 0) { +#ifdef TM_ZONE + negative = t->TM_ZONE[0] == '-'; +#else + negative + = (t->tm_isdst < 0 + || tzname[t->tm_isdst != 0][0] == '-'); +#endif + } + if (negative) { sign = "-"; diff = -diff; } else sign = "+"; -- 2.7.4

3 5

Problem with WORK_AROUND_QTBUG_53071
by Bradley White 08 Jan '17

08 Jan '17

Happy leap second. In 2016i Pacific/Tongatapu changed to: (1) use numeric time zone abbreviations, and (2) observe DST from the first Sunday in November through the third Sunday in January. That is, its POSIX future rule became "<+13>-13<+14>,M11.1.0,M1.3.0/3". (1) results, under WORK_AROUND_QTBUG_53071, in zic adding a "y2038_boundary - 1" (i.e., 2038-01-19 03:14:07 +00:00) no-op transition to the end of the generated transitions. So, the Pacific/Tongatapu zoneinfo file looks like ... : 2115810000 gmtoff=46800 is_dst=F abbr="+13" 2140606800 gmtoff=50400 is_dst=T abbr="+14" 2147483647 gmtoff=50400 is_dst=T abbr="+14" When loading Pacific/Tongatapu at runtime, (2) results in tzloadbody() generating additional transitions ... : 2140606800 gmtoff=50400 is_dst=T abbr="+14" 2147259600 gmtoff=46800 is_dst=F abbr="+13" 2172661200 gmtoff=50400 is_dst=T abbr="+14" 2178709200 gmtoff=46800 is_dst=F abbr="+13" : When those generated transitions are patched onto the end of the zic transitions, we end up with ... 2115810000 gmtoff=46800 is_dst=F abbr="+13" 2140606800 gmtoff=50400 is_dst=T abbr="+14" 2147483647 gmtoff=50400 is_dst=T abbr="+14" 2172661200 gmtoff=50400 is_dst=T abbr="+14" 2178709200 gmtoff=46800 is_dst=F abbr="+13" This is wrong. The presence of the 2147483647 transition caused us to drop the 2147259600 transition. That is, we lost the shift out of DST at 2038-01-17 02:00:00 +13:00 (2038-01-16 13:00:00 +00:00). One solution would be to trim trailing, no-op transitions from the end of the zic transitions before adding the rule-generated ones. The reference implementation doesn't need them. Bradley

2 7

[PATCH] Update to cite current version of POSIX.1
by Sanjeev 07 Jan '17

07 Jan '17

There has been a new Technical Corrigendum issued, and incorporated in the 2016 Edition. Slight reorder of the citation to conform to how Opengroup likes it. --- Theory | 9 +++++---- 1 file changed, 5 insertions(+), 4 deletions(-) diff --git a/Theory b/Theory index 22164f4..f2a8dde 100644 --- a/Theory +++ b/Theory @@ -39,10 +39,11 @@ also available. The tz code is upwards compatible with POSIX, an international standard for UNIX-like systems. As of this writing, the current edition of POSIX is: - The Open Group Base Specifications Issue 7 - IEEE Std 1003.1, 2013 Edition - <http://pubs.opengroup.org/onlinepubs/9699919799/> - + IEEE Std 1003.1,2016 Edition + The Open Group Technical Standard Base Specifications, Issue 7 + incorporates IEEE Std 1003.1-2008, + IEEE Std 1003.1-2008/Cor 1-2013, + IEEE Std 1003.1-2008/Cor 2-2016 ----- Names of time zone rules ----- -- 2.10.2

5 4