November 2011 - 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,

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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.

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a patch for zic.c to allow 'follow rules'
by Alois Treindl Sept. 10, 2013

Sept. 10, 2013

Dear Arthur, I have been preparing a small modification for zic.c which will allow it to understand a 'follow rule' in zone files, like this: # experimental table for Geneva, to test the 'follow' mechanism Zone Europe/Geneva 0:24:37 - LMT 1848 Sep 12 0:24:37 - GET 1894 Jun # Geneva MTime 0 follow Europe/Zurich For test purposes, one can simply insert this zone in the europe file. The feature is helpful in the extension of tzdata to cover complete timezone history. For this purpose, about 1000 additional zone files need to be written, and to be maintained. The process to do so has started in the astrological community, as it needs a complete pre-1970 timezone history. I will not bother you with details. I intend to help creating and maintaining a set of files like 'europe_hist', 'asia_hist' etc which contain the additional zones. The 'follow rule' will allow to keep these extra zone files very small, as usually the additional zones will all have a cross-over moment into a regular tzdata zone. I have for the moment called the modified zic source file zicx.c and prepared a patch file for zic.c to implement the 'follow rule' feature. I have tried to keep the modification very small. Please have a look at the patch, and check for the errors I have probably made. Description of the code: ------------------------ The follow rule must be the last line in a zone, and recursion is not allowed. It is parsed in inzsub() which reacts on GMTOFF = 0 and the word 'follow' in the RULE field. The zone line is stored in zones[] with a special value z_gmtoff = FOLLOW_MARK and the zone_name to follow in field z_rule (which is abused for this purpose). Before the call to outzone() the two sets of zone lines are patched together in a temporary array, so that outzone() and all functions deeper down() need not be modified. Patch ----- --- zic.c 2011-03-09 20:41:27.000000000 +0100 +++ zicx.c 2011-08-25 16:09:04.000000000 +0200 @@ -262,6 +262,17 @@ static int typecnt; #define YR_MAXIMUM 1 #define YR_ONLY 2 +/* +** follow rules, added by Alois Treindl August 2011 +** Zones may end with a line: 0 follow zone_name +** which the parser will represent with FOLLOW_MARK in z_gmtoff, +** and the zone name in z_rule. +** Before the call to outzone() the zone and its follow zone will be +** patched together, so that outzone() sees a regular zone array. +** To keep zone files readable, follow rules cannot be used recursively. +*/ +#define FOLLOW_MARK 999999 + static struct rule * rules; static int nrules; /* number of rules */ @@ -589,7 +600,48 @@ _("%s: More than one -L option specified */ for (j = i + 1; j < nzones && zones[j].z_name == NULL; ++j) continue; - outzone(&zones[i], j - i); + if (zones[j -1].z_gmtoff == FOLLOW_MARK) { + /* copy zone and follow zone into one new array */ + int k,n,m, nrows; + struct zone *xzones, *zp; + nrows = j - i - 1; + zp = &zones[j - 1]; /* line with the follow rule */ + xzones = (struct zone *) (void *) emalloc((int) (nrows * sizeof *xzones)); + for (k = 0; k < nrows; k++) + xzones[k] = zones[i + k]; + /* now find the follow zone in array zones[] */ + for (m = 0; m < nzones; m++) { + if (zones[m].z_name != NULL && strcmp(zp->z_rule, zones[m].z_name) == 0) break; + } + if (m == nzones) { /* error, follow zone not found */ + char *cp; + cp = emalloc(80 + strlen(zp->z_rule) + strlen(zones[i].z_name));; + sprintf(cp, "For zone %s follow zone %s not found, no zonefile created.", zones[i].z_name, zp->z_rule); + eat(zp->z_filename, zp->z_linenum); + error(cp); + ifree(cp); + ifree((void *)xzones); + } + /* now find the next date in the follow zone */ + for (n = m + 1; n < nzones; n++) { + if (zp->z_untiltime < zones[n].z_untiltime) break; + } + /* missing errorcode for case n == nzones, + * assume we are still in same follow zone. + * The follow zone part we need starts at zones[n]. + * Now find where follow zone ends, will be m. + */ + for (m = n; m < nzones && zones[m].z_name == NULL; ++m) + continue; + xzones = (struct zone *) (void *) erealloc((char *) xzones, (int) ((nrows + m - n) * sizeof *xzones)); + for (k = 0; k < m - n; k++) + xzones[nrows + k] = zones[n + k]; + nrows += m - n; + outzone(&xzones[0], nrows); + ifree((void *) xzones); + } else { + outzone(&zones[i], j - i); + } } /* ** Make links. @@ -784,7 +836,7 @@ associate(void) } for (i = 0; i < nzones; ++i) { zp = &zones[i]; - if (zp->z_nrules == 0) { + if (zp->z_nrules == 0 && zp->z_gmtoff != FOLLOW_MARK) { /* ** Maybe we have a local standard time offset. */ @@ -1079,11 +1131,23 @@ const int iscont; return FALSE; } } - z.z_rule = ecpyalloc(fields[i_rule]); - z.z_format = ecpyalloc(fields[i_format]); - if (max_format_len < strlen(z.z_format)) - max_format_len = strlen(z.z_format); - hasuntil = nfields > i_untilyear; + /* check for 0 follow zonename + ** zonename must contain at least one /, and follow must be + * 'follow' or an abbreviation thereof. + */ + if (z.z_gmtoff == 0 && strchr(fields[i_format], '/') != NULL + && itsabbr(fields[i_rule], "follow")) { + z.z_gmtoff = FOLLOW_MARK; + z.z_rule = ecpyalloc(fields[i_format]); + z.z_format = ""; + hasuntil = FALSE; /* no continue of zone now */ + } else { + z.z_rule = ecpyalloc(fields[i_rule]); + z.z_format = ecpyalloc(fields[i_format]); + if (max_format_len < strlen(z.z_format)) + max_format_len = strlen(z.z_format); + hasuntil = nfields > i_untilyear; + } if (hasuntil) { z.z_untilrule.r_filename = filename; z.z_untilrule.r_linenum = linenum;

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Unsubscribe
by Brenda Burnell (bburnell) May 7, 2012

May 7, 2012

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New zone for DE, split from Europe/Berlin
by Mr tobias conradi April 30, 2012

April 30, 2012

The German exclave of Büsingen (http://www.buesingen.de/) surrounded by the Swiss canton Schaffhausen, did not start observing DST in 1980 as the rest of DE (West Germany at that time) and DD (East Germany at that time) did. DD merged into DE, the area is currently covered by code DE in ISO 3166-1, which in turn is covered by the zone Europe/Berlin. Source for the time in Büsingen 1980: http://www.videoportal.sf.tv/video?id=c012c029-03b7-4c2b-9164-aa5902cd58d3 Suggested zone name: Europe/Busingen (removing diacritics as does UN/LOCODE) OR Europe/Buesingen (resolving as in German language) -- Tobias Conradi Rheinsberger Str. 18 10115 Berlin, Germany http://tobiasconradi.com

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apparent-solar-time zone possible cleanup
by Zefram March 4, 2012

March 4, 2012

The apparent-solar-time zones seem to be misusing the "zzz" indicator, and they have poor boundary behaviour. The attached patch makes these changes that seem like a good idea to me: * abbreviation "LAT", for "Local Apparent Time", during the period where the zone provides LAT behaviour * additional apparent-time offset entry for Dec 31 of previous year, so that the ruleset provides LAT correctly for the first half of Jan 1 * range of validity of the LAT data defined strictly as starting and ending at Jan 1 00:00 UT * zone marked as disused outside the range of validity of the LAT data Also, thoughts on apparent solar time more generally: the existing solar?? files inconveniently can't be merged because the result would have more than 256 distinct offsets. However, if the resolution of the offsets were dropped from 5 s to 10 s, then there would be only 186 distinct offsets within the range of the equation of time, so we could have an apparent-time ruleset covering as many years as we're interested in. That could allow incorporating those rules into the regular Asia/Riyadh zone, rather than requiring these hacky separate zones. The apparent-time ruleset could also be formulaically generated at build time, rather than explicitly included in the source tarball. -zefram

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Civil suit; ftp shutdown; mailing list shutdown
by Olson, Arthur David (NIH/NCI) [E] Feb. 12, 2012

Feb. 12, 2012

A civil suit was filed on September 30 in federal court in Boston; I'm a defendant; the case involves the time zone database. The ftp server at elsie.nci.nih.gov has been shut down. The mailing list will be shut down after this message. Electronic mail can be sent to me at arthurdavidolson(a)gmail.com. I hope there will be better news shortly. --ado

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Moldova in zone.tab
by Zefram Jan. 20, 2012

Jan. 20, 2012

Now that Moldova has split into two timezones, the zones need descriptions in zone.tab. However, tzdata2011m only gives a description for the new Europe/Tiraspol, leaving the old Europe/Chisinau with no description. This violates the format of zone.tab. (Which makes my automatic repackaging for CPAN protest.) Following examples such as Chile and Greenland, I believe the appropriate description for Europe/Chisinau is "most locations". -zefram

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Timezone abbreviations
by Alain Petit Jan. 5, 2012

Jan. 5, 2012

[As I was using an incorrect email, I am resending. Apologies if duplicates were issued] Hi I am looking at the following timezone definition # Zone NAME GMTOFF RULES FORMAT [UNTIL] Zone America/Metlakatla 15:13:42 - LMT 1867 Oct 18 -8:46:18 - LMT 1900 Aug 20 12:00 -8:00 - PST 1942 -8:00 US P%sT 1946 -8:00 - PST 1969 -8:00 US P%sT 1983 Oct 30 2:00 -8:00 US MeST I am trying to make sense of the MeST [the format]. I think PST means "Pacific Standard Time", and P%sT becomes PST or PDT according to the US rule in effect [and making it Pacific Standard Time or Pacific Daylight Time]. However I cannot figure out what MeST would be, apart from Metlakatla Standard Time ? [I found MEST - Middle European Standard Time, but Metlakatla is not in Europe] Searching for Metlakatla [google] always refers it as AKST [Alaska Standard Time]. So 2 questions a) What would MeST mean? [and why no '%s' for it?] b) Where can I find the meaning of these abbreviations [as I will probably find others that will confuse me in the future] Thanks -Alain

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Fiji DST 2011/12 change (again)
by Ken Rylander Nov. 29, 2011

Nov. 29, 2011

Hi, Another change to the Fiji DST end date. In the TZ database the end date for Fiji DST 2012, is currently Feb 26. This has been changed to Jan 22. >From www.fiji.gov.fj:<http://www.fiji.gov.fj:> Amendments to daylight savings Ministry of Information Oct 17 |13:59 pm The end of daylight saving scheduled initially for the 26th of February 2012 has been brought forward to the 22nd of January 2012. The commencement of daylight saving will remain unchanged and start on the 23rd of October, 2011. An official gazette reflecting this change will be released early this week. -ends- http://www.fiji.gov.fj/index.php?option=com_content&view=article&id=5017:am… Please add to next tz update. Cheers, /Ken ________________________________ Notice of Confidentiality: The information contained in this communication is intended solely for the use of the individual or entity to whom it is addressed and others authorized to receive it. It may contain confidential or legally privileged information. If you are not the intended recipient you are hereby notified that any disclosure, copying, distribution or taking any action in reliance on the contents of this information is strictly prohibited and may be unlawful. If you have received this communication in error, please notify us immediately by responding to this email and then delete it from your system.

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Reading binary files
by Thom Hehl Nov. 17, 2011

Nov. 17, 2011

OK, I give up. I've tried looking at the source code and it's hopeless. Can someone please explain to me how to read the binary files and turn it into timezone information? All I need to do is write a function that will take a UTC date and convert it into a timezone with a name that I specify and convert it back again. (I understand there are precision issues with the last one.) The code is not commented and I can find no documents. Please, I beg you, help me.

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U.S. abbreviations in 1942
by Garrett Wollman Nov. 15, 2011

Nov. 15, 2011

The U.S. went on permanent DST for the duration of World War II starting on February 9, 1942. The following quotation from /Broadcasting/ magazine of 1942-02-02 sheds some more light on abbreviations used in the U.S. during the early 1940s: : At present, times for network programs are nationally released in : accordance with their broadcasts on the East Coast and are labelled : EST. In previous years, during the months that daylight saving time : was in effect in certain parts of the country, including New York, : the designation was changed to EDST for that period. : [... T]he MBS publicity department stated that it will follow the : custom of other years and label program times as EDST. NBC said : that [...] Red Netowrk programs would be shown as EST after Feb. 9. : [...] CBS has announced that "concurrent with national daylight : saving beginning Feb. 9, Columbia network's time designation on news : releaess is Eastern Time. This phrase was chosen because the time : is no longer standard and because, with national daylight saving, : EDST seems unessential." -GAWollman

1 0

Barnaby
by Thom Hehl Nov. 9, 2011

Nov. 9, 2011

OK, first pass of http://code.google.com/p/barnaby is available for download of the source. This is a C++ library with two functions: 1) List all of the timezones 2) For a given timezone name, convert UTC to that timezone It will build a DLL for you if you open the project using Visual C++. The timezone data is only version 2011i, so I will need to update it soon. Please let me know any and all feedback. Blessings!

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FW: Barnaby
by Thom Hehl Nov. 8, 2011

Nov. 8, 2011

>You're using zone.tab as a canonical list of timezones, which it isn't. >zone.tab is only useful for selecting timezones via countries; for a >list of all timezones you can serve you should just look at the tzfiles. Did you read the readme? That is the next thing I'm going to fix. >Your usage of time_t is not appropriate. The type you want there is >dictated by the tzfile format, not by libc. The API needs to use time_t, so the usage is dictated by the use case, not by the tzfile, which is why it's appropriate. >You're doing a linear search (in transitionTimesIndex) that should really >be a binary search. Yeah, that can be optimized. The problem with doing a binary search is that you're not looking for an equal condition, but the smallest gap the thing you're looking for fits into. I'm aware that a binary search would improve performance some, but didn't devote time to it yet. Again, this is a beta drop designed to get the job done so I can move on with other priorities that pay money. :) >Overall it looks like you're interpreting (the 32-bit part of) the tzfile >correctly, but I find the code too messy to be sure. >You have some instance methods that should be class methods ("static"). >There is much else that is poor about your object model, but that's all >off topic for this list. Feel free to email me off list as you please for any improvements you might suggest. As I indicated in the read-me there is much room for improvement, but this meets my current needs. Open source is all about refining code over iterations, right? Whatever changes you'd like to suggest will be re-visited when I get some time to come back and work on this more. Thanks for the excellent feedback. -----Original Message----- From: Zefram [mailto:zefram@fysh.org] Sent: Tuesday, November 08, 2011 12:44 PM To: Thom Hehl Cc: tz(a)iana.org Subject: Re: [tz] Barnaby Thom Hehl wrote: >http://code.google.com/p/barnaby You're using zone.tab as a canonical list of timezones, which it isn't. zone.tab is only useful for selecting timezones via countries; for a list of all timezones you can serve you should just look at the tzfiles. Your usage of time_t is not appropriate. The type you want there is dictated by the tzfile format, not by libc. You're doing a linear search (in transitionTimesIndex) that should really be a binary search. Overall it looks like you're interpreting (the 32-bit part of) the tzfile correctly, but I find the code too messy to be sure. You have some instance methods that should be class methods ("static"). There is much else that is poor about your object model, but that's all off topic for this list. -zefram

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Decoding timezone data
by Thom Hehl Nov. 8, 2011

Nov. 8, 2011

OK, so I'm making some progress on my library. I'm attempting to read the timezone information for America/Kentucky/Louisville. When I run through the values for transition times, I get 177 values such as follows: 2661690496, 2693140096, 2759063296, ... The docs say these transition times are in values returned by the c time function, which returns seconds since midnight, 1/1/1970. If that is the case, then the three values above convert to: May 6, 2054 at 2:28:16 PM May 5, 2055 at 2:28:16 PM June 6, 2057 at 2:28:16 PM These are nowhere near the DST conversion dates for these years and are moving forward. This appears incorrect. Can someone show me what I'm doing wrong? Thanks.

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"Standard byte order"
by Thom Hehl Nov. 8, 2011

Nov. 8, 2011

I'm assuming that "Standard byte order" referred to over and over in the docs means Most Significant Byte first? It should really be documented that way. As far as I know, there is no standard byte order.

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Re: [tz] Australian time zone abbreviations
by Shaun Bouckaert Nov. 8, 2011

Nov. 8, 2011

On 6 November 2011 20:51, Eric Ulevik <eulevik(a)gmail.com> wrote: > On Sun, Nov 6, 2011 at 9:20 PM, Shaun Bouckaert > <shaun.bouckaert(a)gmail.com> wrote: > [snip]> http://australia.gov.au/about-australia/our-country/time > [snip]> I believe that the abbreviations used on the federal > government> website should be used. > Time zones in Australia are legislated by acts of state governments, > not the federal government. The acts mostly refer to "summer time" and > "standard time". > > Eg. South Australia: > http://www.austlii.edu.au/au/legis/sa/consol_act/dsa1971165/ > > Regards, > > Eric Ulevik > In the absence of any specific mention in the state legislation of an appropriate abbreviation, and considering the timezones and their abbreviations span multiple states, I see no reason why federal government documentation on the matter shouldn't be recognised, especially considering the only basis for the current system is a couple of AltaVista searches and the opinion of Australian's on the list at the time. Shaun Bouckaert

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Russian TZ Samara has no offset listed since 2010g
by manprsi2 Nov. 7, 2011

Nov. 7, 2011

Hello, Europe/Samara has the follow zone.tab definition since 2010g (no offset listed) RU +5312+05009 Europe/Samara Moscow - Samara, Udmurtia It used to be RU +5312+05009 Europe/Samara Moscow+01 - Samara, Udmurtia Samara changed to Moscow but all the other regions are listed with an offset even if +00 (Volgograd, Moscow) while Samara is not. I can not tell by searching the mail archive if the change this way was intentional or not? Thanks - Manpreet

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Australian time zone abbreviations
by Shaun Bouckaert Nov. 6, 2011

Nov. 6, 2011

Having long been irked by the fact that the abbreviation for Brisbane is EST, as opposed to AEST, I read through the time zone data file and found that the reason for this was a discussion back in 2001. I'm not sure if this existed then, but there is a federal government web page that lists the time zones and their abbreviations. http://australia.gov.au/about-australia/our-country/time ================================================================================ Time zones With a land mass close to 7.7 million square kilometres, Australia is the world’s sixth largest country and is divided into three separate time zones. Australian Eastern Standard Time (AEST) Covers the eastern states of Queensland, New South Wales (with the exception of the town of Broken Hill), Victoria, Tasmania and the Australian Capital Territory. AEST is equal to Coordinated Universal Time plus 10 hours (UTC +10). Australian Central Standard Time (ACST) Covers the state of South Australia, the town of Broken Hill in western New South Wales and the Northern Territory. ACST is equal to Coordinated Universal Time plus 9 ½ hours (UTC +9 ½). Australian Western Standard Time (AWST) Covers Western Australia. AWST is equal to Coordinated Universal Time plus 8 hours (UTC +8). Daylight saving Daylight Saving Time (DST) is the practice of advancing clocks one hour during the warmer months of the year. In Australia, Daylight saving is observed in New South Wales, Victoria, South Australia, Tasmania, and the Australian Capital Territory. Daylight Saving Time begins at 2am (AEST) on the first Sunday in October and ends at 2am (AEST) (which is 3am Australian Eastern Daylight Time) on the first Sunday in April. Where Daylight saving is observed: NSW, ACT,Vic and Tas move from AEST to Australian Eastern Daylight Time (AEDT), and clocks are advanced to UTC +11. SA and the NSW town of Broken Hill move from ACST to Australian Central Daylight Time (ACDT), and clocks are advanced to UTC +10 ½. Daylight saving is not observed in Queensland, the Northern Territory or Western Australia. ================================================================================ I believe that the abbreviations used on the federal government website should be used. Shaun Bouckaert

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leap seconds (srsly)
by Zefram Nov. 4, 2011

Nov. 4, 2011

In a couple of months, a decision is going to be made about possibly ceasing leap seconds in UTC. If that happens, the tz database is going to be thrown into a world of hurt, as "UTC = GMT" gradually ceases to be a viable approximation. Here are the slides from a talk presented a couple of months ago that provides a useful primer on how the decision would interact with civil and legal time: http://www.cacr.caltech.edu/futureofutc/program/presentations/AAS_11-662_Se… All the presentations from the conference where that was presented, discussing mary aspects of the decision, can be found here: http://www.cacr.caltech.edu/futureofutc/program/ (Information forwarded from the leapsecs mailing list.) -zefram

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Leap seconds
by Thom Hehl Nov. 4, 2011

Nov. 4, 2011

The docs specify that the transition time is based on the return value from the time() function. Does that mean that the leap seconds are automatically adjusted based on that value and the transition time is correct or does that mean that it uses the actual time and I have to adjust first with leap seconds if I want an accurate conversion?

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Thread-safe localtime(3) (was Re: Reading binary files)
by Bennett Todd Nov. 3, 2011

Nov. 3, 2011

Am I missing a fundamental, or would it be reasonable to not necessarily expose the data structure for the parsed conversion data, but instead offer explicit parse routine (returning an opaque blob) and convert routine that takes such a blob as a parameter? Then it should be easy to make tzset(3) utterly trivial -- call the zoninfo parser on getenv(TZ) with locking, and localtime(3) likewise trivial, call the real convert routine with the datastructure cached by the latest tzset.

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Re: [tz] Reading binary files
by Thom Hehl Nov. 2, 2011

Nov. 2, 2011

Not if you are writing applications that need high performance processing of multiple timezones and access from multiple languages and platforms. Besides, we're multi-threaded. Changing environment variables is simply not an option. Yikes! Can you say race condition. From: bent(a)latency.net [mailto:bent@latency.net] On Behalf Of Bennett Todd Sent: Wednesday, November 02, 2011 9:09 AM To: Thom Hehl Subject: Re: [tz] Reading binary files The binary files are a distraction. What you want to do is set the environment variable TZ to the name of the zone you want, then call tzset which is what consults the database and prepares for conversion. Then localtime(3) will translate a time_t (seconds since the epoch) to hours, minutes, seconds, etc in the local timezone. For translating back and forth you repeatedly reset TZ, call tzset(3), and localtime(3). Those are the standards for Unix, the native home of the zoneinfo database. If you're on a different system details may vary. But on Unix the database is probably already installed in your system and the subroutines you need are already compiled into the system library.

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tzdata2011n.tar.gz
by Robert Elz Nov. 2, 2011

Nov. 2, 2011

The file ftp://munnari.oz.au/pub/tzdata2011n.tar.gz ...is now available; this reflects changes circulated last week, and weekend, on the time zone mailing list, and summarised here. There are three changes of note - most urgently, Cuba (America/Havana) has extended summer time by two weeks, now to end on Nov 13, rather than the (already past) Oct 30. Second, the Pridnestrovian Moldavian Republic (Europe/Tiraspol) decided not to split from the rest of Moldova after all, and consequently that zone has been removed (again) and reinstated in the "backward" file as a link to Europe/Chisinau. And third, the end date for Fiji's summer time this summer was moved forward from the earlier planned Feb 26, to Jan 22. Apart from that, Moldova (MD) returns to a single entry in zone.tab (and the incorrect syntax that was in the 2011m version of that file is so fixed - it woudl have been fixed in a different way had this change not happened - that's the "missing" sccs version id). Once again, no signatures, but hash digests using several different algorithms are appended to this message so you can verify the file that you fetch. These were generated using the pkgtools/digest program from NetBSD's pkgsrc. kre MD5 (tzdata2011n.tar.gz) = 20dbfb28efa008ddbf6dd34601ea40fa RMD160 (tzdata2011n.tar.gz) = 4a2a06ada05aca1ea99767caa1b23c6fcb88bcd3 SHA1 (tzdata2011n.tar.gz) = 5435fae9844dc89f9d418aa956e161e23d1babdf SHA512 (tzdata2011n.tar.gz) = 2081fa44f00ace6539ecc1296f454fb96bb4afa61114ffbc58f46f82ef8ba2cfa22d7e48456a293502433dccca6d921db8f70d6c6e18a074996cfeb74534d2df TIGER (tzdata2011n.tar.gz) = 28b009b1e0e7126c2430270efd1aae89237be7c00b3ad2a5 WHIRLPOOL (tzdata2011n.tar.gz) = e7004894829c63baef91fd5fbc14b77a7fbd92ae2a6e001f279c8b1169bd5be009ae07af336ddaca148eadeba3383896b247a19c9e72d894e80ad60fc896f3f3

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Query about update in timezone database
by Mangala Arjun Nov. 2, 2011

Nov. 2, 2011

Hi, I am new member to this mailing list. When an update for timezone database is present , will it be intimated in this mailing list ? Thanks and Regards Mangala Arjun

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