July 2017 - 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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Turks & Caicos to resume DST; details unclear
by Paul Eggert Oct. 31, 2017

Oct. 31, 2017

According to an article published in the Bahamas website Magnetic Media, the cabinet of Turks & Caicos decided on Thursday to resume the practice of daylight saving time starting in 2018. The article does not give enough details to update the database (it confuses summer with winter time, among other things). My guess is that Turks & Caicos will revert to its pre-2015 practice of staying in sync with New York, which means that tzdb's predictions for its UTC offsets will become wrong in November 2018, and the abbreviations and tm_isdst flag will become wrong some time between March and November 2018 (although the article implies April, this could well be an error). When the cabinet and/or the Turks & Caicos Weekly News get around to publishing the details of the decision, we should be able to update tzdb to reflect this change with some accuracy. Gordon Z. PDM to reinstate Daylight Savings Time. Magnetic Media 2017-07-20. http://magneticmediatv.com/2017/07/pdm-to-reinstate-daylight-savings-time/ ("PDM" is the People's Democratic Movement.)

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Alberta Tory leadership candidate petitions to drop DST and move to CT
by Brian Inglis Sept. 19, 2017

Sept. 19, 2017

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

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Syntax highlighting for Sublime Text
by Gilmore Davidson Aug. 16, 2017

Aug. 16, 2017

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

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[PROPOSED] Detroit did not observe DST in 1967
by Paul Eggert July 27, 2017

July 27, 2017

* NEWS: Document this. * northamerica (Detroit): Remove bogus 1967 rules that were taken from Shanks. --- NEWS | 2 ++ northamerica | 15 +++++++++++++-- 2 files changed, 15 insertions(+), 2 deletions(-) diff --git a/NEWS b/NEWS index 64d5c91..93633a5 100644 --- a/NEWS +++ b/NEWS @@ -4,6 +4,8 @@ Unreleased, experimental changes Changes to past time stamps + Detroit did not observe DST in 1967. + Use railway time for Asia/Kolkata before 1941, by switching to Madras local time (UT +052110) in 1870, then to IST (UT +0530) in 1906. Also, treat 1941-2's +0630 as DST, like 1942-5. diff --git a/northamerica b/northamerica index 651681d..b42aeb4 100644 --- a/northamerica +++ b/northamerica @@ -1040,12 +1040,23 @@ Zone America/Kentucky/Monticello -5:39:24 - LMT 1883 Nov 18 12:20:36 # one hour in 1914." This change is not in Shanks. We have no more # info, so omit this for now. # +# From Paul Eggert (2017-07-26): +# Although Shanks says Detroit observed DST in 1967 from 06-14 00:01 +# until 10-29 00:01, I now see multiple reports that this is incorrect. +# For example, according to a 50-year anniversary report about the 1967 +# Detroit riots and a major-league doubleheader on 1967-07-23, "By the time +# the last fly ball of the doubleheader settled into the glove of leftfielder +# Lenny Green, it was after 7 p.m. Detroit did not observe daylight saving +# time, so light was already starting to fail. Twilight was made even deeper +# by billowing columns of smoke that ascended in an unbroken wall north of the +# ballpark." See: Dow B. Detroit '67: As violence unfolded, Tigers played two +# at home vs. Yankees. Detroit Free Press 2017-07-23. +# http://www.freep.com/story/sports/mlb/tigers/2017/07/23/detroit-tigers-1967… +# # Most of Michigan observed DST from 1973 on, but was a bit late in 1975. # Rule NAME FROM TO TYPE IN ON AT SAVE LETTER Rule Detroit 1948 only - Apr lastSun 2:00 1:00 D Rule Detroit 1948 only - Sep lastSun 2:00 0 S -Rule Detroit 1967 only - Jun 14 2:00 1:00 D -Rule Detroit 1967 only - Oct lastSun 2:00 0 S # Zone NAME GMTOFF RULES FORMAT [UNTIL] Zone America/Detroit -5:32:11 - LMT 1905 -6:00 - CST 1915 May 15 2:00 -- 2.13.3

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Re: [tz] libc-2.25.90.pot
by Paul Eggert July 20, 2017

July 20, 2017

On 07/20/2017 07:57 AM, Siddhesh Poyarekar wrote: > Oh I meant PRIdLINENO, not PRIdMAX. I suppose using PRIdMAX directly > might work since gettext seems to recognize the other PRI* macros. Yes, PRIdMAX should work. The zic.c code uses the macro (as opposed to just %jd) to be portable to pre-C99 libraries. I installed the attached patch into the upstream tzdb sources; the zic.c part of it should work for glibc too. Thanks for reporting the problem.

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[PROPOSED] Use more up-to-date citation for leap seconds
by Paul Eggert July 18, 2017

July 18, 2017

* leapseconds.awk: Cite Levine 2016 instead of Quinn 1991. --- leapseconds.awk | 8 +++----- 1 file changed, 3 insertions(+), 5 deletions(-) diff --git a/leapseconds.awk b/leapseconds.awk index 405ce3a..66eb64d 100644 --- a/leapseconds.awk +++ b/leapseconds.awk @@ -17,11 +17,9 @@ BEGIN { print "# The International Earth Rotation and Reference Systems Service" print "# periodically uses leap seconds to keep UTC to within 0.9 s of UT1" print "# (which measures the true angular orientation of the earth in space); see" - print "# Terry J Quinn, The BIPM and the accurate measure of time," - print "# Proc IEEE 79, 7 (July 1991), 894-905 <http://dx.doi.org/10.1109/5.84965>," - print "# reprinted in: Hackman C, Sullivan DB (eds), Time and frequency measurement," - print "# American Association of Physics Teachers (1996)," - print "# <http://tf.nist.gov/general/pdf/1168.pdf>, 75-86." + print "# Levine J. Coordinated Universal Time and the leap second." + print "# URSI Radio Sci Bull. 2016;89(4):30-6. doi:10.23919/URSIRSB.2016.7909995" + print "# http://ieeexplore.ieee.org/document/7909995/" print "# There were no leap seconds before 1972, because the official mechanism" print "# accounting for the discrepancy between atomic time and the earth's rotation" print "# did not exist until the early 1970s." -- 2.7.4

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Pedantic correction to Theory regarding size of time zone names
by Howard Hinnant July 16, 2017

July 16, 2017

Line 91 of Theory: https://github.com/eggert/tz/blob/master/Theory#L91 reads: > A file name component must not exceed 14 characters … I found one exception to this rule: The Link: Canada/East-Saskatchewan in backward. East-Saskatchewan is 17 characters. I recommend simply changing the 14 to 17. Howard

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Unix time_t hits 1.5Gs early Friday UTC
by Brian Inglis July 14, 2017

July 14, 2017

Unix time_t will hit 1 500 000 000 at 2017 Jul 14 Fri 02:40:00+0000 which is Thursday evening in North America: $ for city in Vancouver Edmonton Regina Winnipeg Toronto Halifax St_Johns; do TZ=America/$city date -d@1500000000 +%c\ %Z; done 2017 Jul 13 Thu 19:40:00 PDT 2017 Jul 13 Thu 20:40:00 MDT 2017 Jul 13 Thu 20:40:00 CST 2017 Jul 13 Thu 21:40:00 CDT 2017 Jul 13 Thu 22:40:00 EDT 2017 Jul 13 Thu 23:40:00 ADT 2017 Jul 14 Fri 00:10:00 NDT and on some other time scales, which may not be aligned to UTC: $ gpstime.sh @1500000000 2017 Jul 14 Fri 02:40:00+0000 JD 2457948.611111 MJD 57948.111111 ToD 9599 NTP 3708988800 Unix 1500000000 TAI-UTC 37 TAI-GPS 19 GPS-UTC 18 GPS We 1957 Cy 1 Wn 933 Wa 165 ToW 441618 DoW 5 ToD 9618 As usual there will be some Europeans staying up late to celebrate and party. Unix time won't hit 1.5Gis until: $ gpstime.sh @`bc <<< 2^30*3/2` 2021 Jan 14 Thu 08:25:36+0000 JD 2459228.851111 MJD 59228.351111 ToD 30336 NTP 3819601536 Unix 1610612736 TAI-UTC 37 TAI-GPS 19 GPS-UTC 18 GPS We 2140 Cy 2 Wn 92 Wa 92 ToW 375954 DoW 4 ToD 30354 and it will be a while before it hits 2Gs: $ gpstime.sh @2000000000 2033 May 18 Wed 03:33:20+0000 JD 2463735.648148 MJD 63735.148148 ToD 12799 NTP 4208988800 Unix 2000000000 TAI-UTC 37 TAI-GPS 19 GPS-UTC 18 GPS We 2784 Cy 2 Wn 736 Wa 224 ToW 272018 DoW 3 ToD 12818 -- Take care. Thanks, Brian Inglis, Calgary, Alberta, Canada

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Use GST abbreviation for Asia/Dubai, Asia/Muscat
by Mohamed Akram July 14, 2017

July 14, 2017

I noticed Asia/Dubai and Asia/Muscat currently use +04, but there is an existing abbreviation (GST - Gulf Standard Time).

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Etc/GMT timezone offsets are inverted
by Pedro A. López-Valencia July 11, 2017

July 11, 2017

I just noticed that all GMT+- timezones are inverted so that GMT+5 is really GMT-5. This applies to all GMT-offset timezone definitions. -- https://about.me/palopezv

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IERS Bulletin C54
by Michael Deckers July 11, 2017

July 11, 2017

The IERS has issued Bulletin C54 which assures that no leap second will occur near 2018-01-01. Interestingly, the issue date 2017-07-06 in the txt version at [https://datacenter.iers.org/eop/-/somos/5Rgv/getTX/16/bulletinc-054.txt] differs from the issue date 2017-07-09 in the xml version at [https://datacenter.iers.org/eop/-/somos/5Rgv/latestXL/16/bulletinc-054.txt/…] Michael Deckers. --- This email has been checked for viruses by Avast antivirus software. https://www.avast.com/antivirus

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backzone/Europe/Guernsey
by Michael Deckers July 10, 2017

July 10, 2017

For the connoisseurs of olde time stamps: The "LMT location" for backzone/Europe/Guernsey is given as "49.27N -2.33E" -- seemingly in degrees and decimal fractions of degrees. But the point ( +49.27°, -2.33° ) = ( +49°16′12″, -002°19′48″ ) is in open waters about 15 km south of Guernsey and east of Sark in the Channel. The point ( +49°27′, -002°33′ ), however, is in St Peter Port on the island, so that arc minutes and not hundredths of degrees must be meant. This also agrees with zone.tab. Hence: -# LMT Location - 49.27N -2.33E - St.Peter Port +# LMT Location - 49°27′N -2°33′E - St.Peter Port -Zone Europe/Guernsey -0:09:19 - LMT 1913 Jun 18 +Zone Europe/Guernsey -0:10:12 - LMT 1913 Jun 18 Michael Deckers. --- This email has been checked for viruses by Avast antivirus software. https://www.avast.com/antivirus

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Re: [tz] TZ & AIX
by Paul Eggert July 8, 2017

July 8, 2017

Jorge Fábregas wrote: > https://www.ibm.com/developerworks/aix/library/au-aix-olson-time-zone/index… Thanks for the heads-up. I installed the attached.

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Orillia's 1912 DST pops up again in Toronto Star
by Paul Eggert July 8, 2017

July 8, 2017

Today's Toronto Star reports on the two-week daylight saving time interlude in Orillia, Ontario. Today's article doesn't mention the same newspaper's 1997-10-14 article on the same topic, and it's not clear what's new this time around. Still, the story is amusingly told. Proposed patch attached.

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DST in the (odd) news
by Arthur David Olson July 7, 2017

July 7, 2017

"Alarm clock removed from family's home after 14 years of daily beeping" "Over the years, it beeped at 6.50pm or 7.50pm each day, depending on whether Daylight [Saving] Time was in place." https://www.theguardian.com/us-news/2017/jul/07/alarm-clock-wall-pennsylvan… @dashdashado

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