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Republic of Belarus is considering time zone change due to Russia's change
by Alexander Bokovoy Oct. 10, 2014

Oct. 10, 2014

Hi, a local news site got a comment from PR service of Belarussian National Standardization Committee that government is currently deciding on the time zone change to follow Russia. The decision is not yet made and I was unable to find any other source or reference at any governmental site, which is, unfortunately, typical. http://news.tut.by/society/416667.html (in Russian) -- / Alexander Bokovoy

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Re: [tz] Recent conversions of zones to aliases
by random832＠fastmail.us Oct. 6, 2014

Oct. 6, 2014

On Sat, Oct 4, 2014, at 06:15, Stephen Colebourne wrote: > The key point to remember is that Joda-Time has been running for many > years and has striven very hard to retain backwards compatibility. > Converting aliases to their underlying zone has worked well over many > years, and is far from an unreasonable approach, as it reduces the > effect of older zones such as US-Pacific. The effect of those zones is limited to when the user has actually selected them. For that matter, if aliases were not normalized, you would have _maintained_ backwards compatibility when (in principle - in reality, that was before Joda-Time was even a thing.) the zone name was changed _from_ those older names in the first place. The point of aliases is to limit the impact of changes on users who selected the old name when it was current, by keeping the behavior of their systems the same. "Normalizing" them goes against that principle.

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St Andrews meridian in the 17th century
by Peter Ilieve Oct. 6, 2014

Oct. 6, 2014

Now that we don’t have to think about a possible future Europe/Glasgow zone (postings back in August) for several years at least, here’s a bit of Scottish history to consider instead. St Andrews, on the Fife coast in the east of Scotland, had a meridian line set up some 200 years before Greenwich. Here’s a quote from a press release from the University of St Andrews, who have just created a memorial to mark this line: "The 17th Century Scottish astronomer and scientific pioneer James Gregory laid down a meridian line across the floor of his lab at St Andrews University in 1673, almost 200 years before the Greenwich Meridian was established and arbitrarily adopted as the world’s official prime meridian. "Now St Andrews has recognised Gregory’s remarkable body of work with a permanent public memorial – a solid brass line which follows exactly the line of his meridian and bisects the pavement in South Street, St Andrews.” This story was picked up by The Times and the BBC (and probably others I haven’t seen). As well as the line on the lab floor there was a sighting mark outside a window and a stone marker on a hill 2.4km away. This still exists and is marked on Ordnance Survey maps. Some URLs: The University of St Andrews press release: <http://www.st-andrews.ac.uk/news/archive/2014/title,250213,en.php> BBC piece: <http://www.bbc.co.uk/news/uk-scotland-29474850> The Times piece (which is behind their paywall): <http://www.thetimes.co.uk/tto/news/uk/scotland/article4224136.ece> Map showing St Andrews and Gregory’s Pillar (marked with arrow): <http://www.streetmap.co.uk/idld.srf?X=350994&Y=715496&A=Y&Z=115&lm=1&ax=350…> Peter Ilieve

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[PROPOSED PATCH] * zdump.c (adjusted_yday): Define only if TM_GMTOFF is not defined.
by Paul Eggert Oct. 5, 2014

Oct. 5, 2014

--- zdump.c | 4 +++- 1 file changed, 3 insertions(+), 1 deletion(-) diff --git a/zdump.c b/zdump.c index 37a0926..13bbb0e 100644 --- a/zdump.c +++ b/zdump.c @@ -851,8 +851,9 @@ delta(struct tm * newp, struct tm *oldp) return result; } +#ifndef TM_GMTOFF /* Return A->tm_yday, adjusted to compare it fairly to B->tm_yday. - Assume A and B differ by at most one year. */ + Assume A and B differ by at most one year. */ static int adjusted_yday(struct tm const *a, struct tm const *b) { @@ -861,6 +862,7 @@ adjusted_yday(struct tm const *a, struct tm const *b) yday += 365 + isleap_sum(b->tm_year, TM_YEAR_BASE); return yday; } +#endif /* If A is the broken-down local time and B the broken-down UTC for the same instant, return A's UTC offset in seconds, where positive -- 1.9.1

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coding style for tzcode?
by christos＠zoulas.com Oct. 4, 2014

Oct. 4, 2014

Hello, The code used to be 8-tab BSD formatted, and now it seems that 2 space indentantion is being used, or 4 space, or whatever random spacing (sometimes contination lines follow the opening parenthesis of the function above, other times they don't) in both new code and diffs from the old code. If people don't like the current coding style, let's decide on a style, reformat all the code to the new style and keep it consistent. What we have now is making the code unreadable. Thank you! christos

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Timezone for Moscow is -10800 after installing tzdata-2014g
by Alexander Koblov Oct. 4, 2014

Oct. 4, 2014

Hi All! My timezone is Europe/Moscow. After installing tzdata-2014g, tzset sets value for timezone not -14400 as before, but -10800, although time shift will be only in October 26th. Is this the expected behavior, or maybe I don't understand something? Please see below program I use for the test and output from console. Notice, how depends on what version of tzdata is installed value of timezone is different, although current time is the same. My question is: Why tzdata-2014g returns timezone for the Europe/Moscow -10800 (3 hours)? As far as I understand timezone for Moscow should be changed on the night of 25/26 October. Thank you, Alexander. ========== #include <iostream> #include <ctime> #include <cstdlib> using namespace std; int main() { tzset(); //set all 4 DST globals using TZ cout<< "the difference between UTC and the local standard time is: "<<timezone<<endl; cout<<boolalpha; //switch to verbal representation of bools cout<<"DST in effect: "<<(bool) daylight<<endl; cout<<"local standard time code: "<<tzname[0]<<endl; cout<<"local standard time code: "<<tzname[1]<<endl; } ========== ============== // With tzdata-2014g-installed [root@Linux jgm]# ./jtz the difference between UTC and the local standard time is: -10800 DST in effect: true local standard time code: MSK local standard time code: MSD [root@Linux jgm]# date Птн Окт 3 14:43:37 MSK 2014 //Let's downgrade to tzdata-2014b [root@Linux jgm]# yum downgrade tzdata-2014b-1.el6.noarch // skip lines Removed: tzdata.noarch 0:2014g-1.el6 Installed: tzdata.noarch 0:2014b-1.el6 Complete! [root@Linux jgm]# ./jtz the difference between UTC and the local standard time is: -14400 DST in effect: false local standard time code: MSK local standard time code: MSD [root@Linux jgm]# date Птн Окт 3 14:44:05 MSK 2014 //Let's return back to tzdata-2014g [root@Linux jgm]# yum update tzdata //skip lines Updated: tzdata.noarch 0:2014g-1.el6 Complete! [root@Linux jgm]# ./jtz the difference between UTC and the local standard time is: -10800 DST in effect: true local standard time code: MSK local standard time code: MSD [root@Linux jgm]# date Птн Окт 3 14:44:36 MSK 2014 [root@Linux jgm]# ==============

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Handling of uninitialized tm_gmtoff and tm_zone
by random832＠fastmail.us Oct. 2, 2014

Oct. 2, 2014

It is possible that mktime, strftime, etc?, may be called with a struct tm that has not had non-standard members initialized. How does tzcode deal with these cases? (It _looks_ like strftime handles it badly; I can't figure out what, if anything, the mktime implementation does with these members).

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Issue with Jordan timezone
by obulesh kumar Oct. 1, 2014

Oct. 1, 2014

Hi all, I am getting wrong time zone for Jordan in my android device. I am calculating time zone from NITZ information provided by network in Amman country. I am using offset and DST value from NITZ to calculate timezone. Below are the values provided by network on date:15/Jul/2014 OFFSET:10800000 DST:false I am getting from proper timezone for Jordan country in 2013g database version as Asia/Amman. But i am not getting any timezone for Amman country in 2013i database on wards. below is timezone data differences from 2013g to 2013i please find snapshot. [image: Inline image 1] Please help us in resolving this issue. Thanks and Regards, Obulesh

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Aix question
by Donald MacQueen Oct. 1, 2014

Oct. 1, 2014

Hi all, Sorry for the off topic, but does anyone know the procedure for updating tz info on Aix? Google is not my friend today. Thanks in advance. Great work, Paul. -- Donald [|] Joel Cairo: "You always have a very smooth explanation." Sam Spade: "What do you want me to do? Learn to stutter?" - The Maltese Falconn

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Time, Clock, and Calendar Programming In C, by Eric S. Raymond
by random832＠fastmail.us Sept. 30, 2014

Sept. 30, 2014

Eric S. Raymond has written an article about the history of the time.h functions at http://www.catb.org/esr/time-programming/ >From his blog post announcing it (http://esr.ibiblio.org/?p=6311) > The C/UNIX library support for time and calendar programming is a nasty mess of historical contingency. I have grown tired of having to re-learn its quirks every time I’ve had to deal with it, so I’m doing something about that. > > Announcing Time, Clock, and Calendar Programming In C, a document which attempts to chart the historical clutter (so you can ignore it once you know why it’s there) and explain the mysteries. > > What I’ve released is an 0.9 beta version. My hope is that it will rapidly attract some thoroughgoing reviews so I can release a 1.0 in a week or so. More than that, I would welcome a subject matter expert as a collaborator. When I saw it I thought it might be generally interesting to people who subscribe to this list.

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Mehdi Ashrafi
by Mehdi Ashrafi Sept. 29, 2014

Sept. 29, 2014

+989376266654

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(FYI) egypt
by Sebastien WILLEMIJNS Sept. 27, 2014

Sept. 27, 2014

http://journalmetro.com/monde/564625/legypte-change-encore-dheure/ i think you know that....

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[tz-announce] 2014h release of tz code and data available
by Paul Eggert Sept. 26, 2014

Sept. 26, 2014

The 2014h release of the tz code and data is available. It reflects the following changes, which were either circulated on the tz mailing list or are relatively minor technical or administrative changes: Changes affecting past time stamps America/Jamaica's 1974 spring-forward transition was Jan. 6, not Apr. 28. Shanks says Asia/Novokuznetsk switched from LMT (not "NMT") on 1924-05-01, not 1920-01-06. The old entry was based on a misinterpretation of Shanks. Some more zones have been turned into links, when they differed from existing zones only for older time stamps. As usual, these changes affect UTC offsets in pre-1970 time stamps only. Their old contents have been moved to the 'backzone' file. The affected zones are: Africa/Blantyre, Africa/Bujumbura, Africa/Gaborone, Africa/Harare, Africa/Kigali, Africa/Lubumbashi, Africa/Lusaka, Africa/Maseru, and Africa/Mbabane. Changes affecting code zdump -V and -v now output gmtoff= values on all platforms, not merely on platforms defining TM_GMTOFF. The tz library's localtime and mktime functions now set tzname to a value appropriate for the requested time stamp, and zdump now uses this on platforms not defining TM_ZONE, fixing a 2014g regression. (Thanks to Tim Parenti for reporting the problem.) The tz library no longer sets tzname if localtime or mktime fails. zdump -c no longer mishandles transitions near year boundaries. (Thanks to Tim Parenti for reporting the problem.) An access to uninitalized data has been fixed. (Thanks to Jörg Richter for reporting the problem.) When THREAD_SAFE is defined, the code ports to the C11 memory model. A memory leak has been fixed if ALL_STATE and THREAD_SAFE are defined and two threads race to initialize data used by gmtime-like functions. (Thanks to Andy Heninger for reporting the problems.) Changes affecting build procedure 'make check' now checks better for properly-sorted data. Changes affecting documentation and commentary zdump's gmtoff=N output is now documented, and its isdst=D output is now documented to possibly output D values other than 0 or 1. zdump -c's treatment of years is now documented to use the Gregorian calendar and Universal Time without leap seconds, and its behavior at cutoff boundaries is now documented better. (Thanks to Arthur David Olson and Tim Parenti for reporting the problems.) Programs are now documented to use the proleptic Gregorian calendar. (Thanks to Alan Barrett for the suggestion.) Fractional-second GMT offsets have been documented for civil time in 19th-century Chennai, Jakarta, and New York. Here are links to the release files: ftp://ftp.iana.org/tz/releases/tzcode2014h.tar.gz ftp://ftp.iana.org/tz/releases/tzdata2014h.tar.gz The files are also available via HTTP as follows: http://www.iana.org/time-zones/repository/releases/tzcode2014h.tar.gz http://www.iana.org/time-zones/repository/releases/tzdata2014h.tar.gz Each release file has a GPG signature, which can be retrieved by appending ".asc" to the above URLs. Copies of these signatures are appended to this message. As usual, links to the latest release files are here: http://www.iana.org/time-zones/repository/tzcode-latest.tar.gz http://www.iana.org/time-zones/repository/tzdata-latest.tar.gz ftp://ftp.iana.org/tz/tzcode-latest.tar.gz ftp://ftp.iana.org/tz/tzdata-latest.tar.gz This release corresponds to commit 651d4deba49e90dd42141bf00dd5e94024100038 dated Thu Sep 25 18:59:03 2014 -0700 and tagged '2014h' in the experimental github repository at <https://github.com/eggert/tz>. Here are the GPG checksums for the release files: -----BEGIN PGP SIGNATURE----- Version: GnuPG v1 iQIcBAABAgAGBQJUJMkaAAoJEO2X6Q5iqn40/xgP/05GMYGaGlB0SdREMb3Tcl37 ofHu8wIlw/zYPqRQsNJX02G0JMm9Ymsxk58K12DrzQvDragun1WEZFYB3qNJjE7c tGd//0NhVUxoGjxQLjrZ6JDr/AlM56iondkbvVzU+2t7mNrNjABg73Ub750fuSzM qt3tpr/+Ba+fOLcKb9uZQqlt6Bc5qAMGXcsBBT0KVeybLjDobaD66yb6kfZ81uNj g3u60H1JKhEe5NduovMLm5NLRtHa4VJCxJki5pwuYgNtuuG9XYpz2vzQ2DuChO8K hjPzR6MpF/KsICAeAsgf+Z6FqDG8LBy39DeyZCwjP9pDPu3VekuW0dpe3Jad/eTC lQB5dubGPkqS6dW1CepoU/Oojdh9CUmlLYIZDCadpE7RfOFqTLLMnEzhVIv2Iluw 5ssTJ0YTomA8XfdVFHoxdZ/woEYg32KF6ssYOOt8+M4xNLNc0zpjLnnwbfpZN1bN SOGnSWkogssPh60Otd60Zy1mx9KnOQAvzQHHMlqRJTCxnVqvLwP2LaUZaYP2nkuo 7WLqGFIjfCc2iIckogkkPotTVNsTuc+FSV6Ck/GMTEHRZrAX34u/iNr2jik7n85s OjEKWz3WKO8Zo7GOk/w7Ekmnt/UzDLEL4RDB2yxWETI8zTxkzfLmEGT/hFVt2JiG yeg7CpXKQtimBKMnMRXl =DxQr -----END PGP SIGNATURE----- -----BEGIN PGP SIGNATURE----- Version: GnuPG v1 iQIcBAABAgAGBQJUJMkaAAoJEO2X6Q5iqn40AcwQAICQe7AszG667Q3EX+jrrvMi np5LQs6UlCJzU+xwpQ0zo8OANPaJRVe11A//j4eWAkZjXGLrpj8GwDNV+AMnPTtB b1UGos9oOitFBsJfXrwRsOUUuMFHUmnIWvIkS6FY3uCG31wXZVUDuRnksUifnB24 Agmz9KI5Be6JHr3d4erzu7rp7gU4FslJ1f4Jvmiy+PnPiMkZJAsf3Lu+O77h/0qR sZNsigf8lXoIakHAQtNiwizk6a1fTAc6VElgk7hwQ9rm1FxiEWWidWv1bF52qbAw kTrdFZEUY5ONe5O8deAf9r3GVKh/3HmMa8Bzf23a8eSDjLrJbhFTb1uZ5P0vRoHu SabrtvhLg8hrUD3RJtEM1rwROaCrdUTfz002DrOX7htA6m9P3af7OmzkWDJ0hlGe EOeAa1YkjcPwGmbYxCWQbexM2KHr4MaIJ1v75lduq1+osEr1dOvzU8/KJzmay59s XWrXXa7ihPyIW+0MCWqTZg8AqTTed9SwMvWRw2gZTM4L23PerfzmM0PzffdY4oCX 9mbCGTKjp+gcMChRJ+Rtf2xlgsHy5uk2tFVCMngL0FW4rm5EIW8R2GhRBrSAkKYb m8KPvc1+ErjK7nkDpFQ1LKk8/H0v08Yk/aYfRmC4IhmJRzB33Ei0ZuWTqU3ilzJ5 743/HDLWaGvpbG639WBU =a4Y0 -----END PGP SIGNATURE----- _______________________________________________ tz-announce mailing list tz-announce(a)iana.org https://mm.icann.org/mailman/listinfo/tz-announce

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tz database
by Zhang, Heather Sept. 24, 2014

Sept. 24, 2014

Hi, I downloaded most recent tz data from http://www.iana.org/time-zones, Time Zone Data v. 2014g (Released 2014-08-28) tzdata2014g.tar.gz<http://www.iana.org/time-zones/repository/releases/tzdata2014g.tar.gz> (278.2kb) Time Zone Code v. 2014g (Released 2014-08-28) tzcode2014g.tar.gz<http://www.iana.org/time-zones/repository/releases/tzcode2014g.tar.gz> (174.0kb) After reading the README file and other document, I understand that the gz is for compiling into unix commands that provide various timezone functions, am I correct? If I m correct, does IANA provide a csv/xls download of tz with daylight saving time info for all cities in the world and delta download periodically? Thanks & Regards, Heather Zhang | Sabre | W: 682.605.2968 | B1 Flex

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[PROPOSED_PATCH] * localtime.c (localtime_tzset): Coalesce two identical flag args.
by Paul Eggert Sept. 23, 2014

Sept. 23, 2014

All callers changed. --- localtime.c | 8 ++++---- 1 file changed, 4 insertions(+), 4 deletions(-) diff --git a/localtime.c b/localtime.c index 30b5fbc..e692513 100644 --- a/localtime.c +++ b/localtime.c @@ -1389,14 +1389,14 @@ localtime_rz(struct state *sp, time_t const *timep, struct tm *tmp) #endif static struct tm * -localtime_tzset(time_t const *timep, struct tm *tmp, bool settz, bool setname) +localtime_tzset(time_t const *timep, struct tm *tmp, bool setname) { int err = lock(); if (err) { errno = err; return NULL; } - if (settz || !lcl_is_set) + if (setname || !lcl_is_set) tzset_unlocked(); tmp = localsub(lclptr, timep, setname, tmp); unlock(); @@ -1406,13 +1406,13 @@ localtime_tzset(time_t const *timep, struct tm *tmp, bool settz, bool setname) struct tm * localtime(const time_t *const timep) { - return localtime_tzset(timep, &tm, true, true); + return localtime_tzset(timep, &tm, true); } struct tm * localtime_r(const time_t *const timep, struct tm *tmp) { - return localtime_tzset(timep, tmp, false, false); + return localtime_tzset(timep, tmp, false); } /* -- 1.9.1

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[PROPOSED PATCH] * northamerica (America/Jamaica): 1974 sprang forward on Jan. 6,
by Paul Eggert Sept. 23, 2014

Sept. 23, 2014

not Apr. 28. * NEWS: Document this. --- NEWS | 2 ++ northamerica | 13 ++++++++++++- 2 files changed, 14 insertions(+), 1 deletion(-) diff --git a/NEWS b/NEWS index 06e7094..8562fae 100644 --- a/NEWS +++ b/NEWS @@ -4,6 +4,8 @@ Unreleased, experimental changes Changes affecting past time stamps + America/Jamaica's 1974 spring-forward transition was Jan. 6, not Apr. 28. + Shanks says Asia/Novokuznetsk switched from LMT (not "NMT") on 1924-05-01, not 1920-01-06. The old entry was based on a misinterpretation of Shanks. diff --git a/northamerica b/northamerica index 0f5ed3c..3d72505 100644 --- a/northamerica +++ b/northamerica @@ -2991,10 +2991,21 @@ Zone America/Tegucigalpa -5:48:52 - LMT 1921 Apr # Shanks & Pottenger give -5:07:12, but Milne records -5:07:10.41 from an # unspecified official document, and says "This time is used throughout the # island". Go with Milne. Round to the nearest second as required by zic. +# +# Shanks & Pottenger give April 28 for the 1974 spring-forward transition, but +# Lance Neita writes that Prime Minister Michael Manley decreed it January 5. +# Assume Neita meant Jan 6 02:00, the same as the US. Neita also writes that +# Manley's supporters associated this act with Manley's nickname "Joshua" +# (recall that in the Bible the sun stood still at Joshua's request), +# and with the Rod of Correction which Manley said he had received from +# Haile Selassie, Emperor of Ethiopia. See: +# Neita L. The politician in all of us. Jamaica Observer 2014-09-20 +# http://www.jamaicaobserver.com/columns/The-politician-in-all-of-us_17573647 +# # Zone NAME GMTOFF RULES FORMAT [UNTIL] Zone America/Jamaica -5:07:11 - LMT 1890 # Kingston -5:07:11 - KMT 1912 Feb # Kingston Mean Time - -5:00 - EST 1974 Apr 28 2:00 + -5:00 - EST 1974 -5:00 US E%sT 1984 -5:00 - EST -- 1.9.3

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Chile 2014 changes
by DONATELLA SABELLICO Sept. 22, 2014

Sept. 22, 2014

Hi, in which "Time Zone Data " are contained the Chile 2014 changes? See http://www.minenergia.cl/ministerio/noticias/generales/ministerio-de-energi… Donatella Sabellico. "One Life. One Love. To love each other" Visit IBM TWA Forum! https://ibm.biz/BdxJFs TWA NewsLetter! http://ibm.biz/Bdxij4 Join SMC Connect community! https://www.ibm.com/developerworks/servicemanagement/ IBM Italia S.p.A. Sede Legale: Circonvallazione Idroscalo - 20090 Segrate (MI) Cap. Soc. euro 347.256.998,80 C. F. e Reg. Imprese MI 01442240030 - Partita IVA 10914660153 Società con unico azionista Società soggetta all?attività di direzione e coordinamento di International Business Machines Corporation (Salvo che sia diversamente indicato sopra / Unless stated otherwise above)

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[PROPOSED PATCH 1/4] Have zdump output gmtoff= even on platforms lacking TM_GMTOFF.
by Paul Eggert Sept. 22, 2014

Sept. 22, 2014

* zdump.c (adjusted_yday, gmtoff): New functions. (show): Use new function gmtoff to output gmtoff= even on platforms that do not define TM_GMTOFF. * NEWS: Document this. --- NEWS | 3 +++ zdump.c | 49 ++++++++++++++++++++++++++++++++++++++++++------- 2 files changed, 45 insertions(+), 7 deletions(-) diff --git a/NEWS b/NEWS index 21e85a7..618ddb7 100644 --- a/NEWS +++ b/NEWS @@ -17,6 +17,9 @@ Unreleased, experimental changes Changes affecting code + zdump -V and -v now output gmtoff= values on all platforms, + not merely on platforms defining TM_GMTOFF. + The tz library's localtime and mktime functions now set tzname to a value appropriate for the requested time stamp, and zdump now uses this on platforms not defining TM_ZONE, fixing a 2014g regression. diff --git a/zdump.c b/zdump.c index 0aa94fc..92dd3c1 100644 --- a/zdump.c +++ b/zdump.c @@ -851,19 +851,54 @@ delta(struct tm * newp, struct tm *oldp) return result; } +/* Return A->tm_yday, adjusted to compare it fairly to B->tm_yday. + Assume A and B differ by at most one year. */ +static int +adjusted_yday(struct tm const *a, struct tm const *b) +{ + int yday = a->tm_yday; + if (b->tm_year < a->tm_year) + yday += 365 + isleap_sum(b->tm_year, TM_YEAR_BASE); + return yday; +} + +/* If A is the broken-down local time and B the broken-down UTC for + the same instant, return A's UTC offset in seconds, where positive + offsets are east of Greenwich. On failure, return LONG_MIN. */ +static long +gmtoff(struct tm const *a, struct tm const *b) +{ +#ifdef TM_GMTOFF + return a->TM_GMTOFF; +#else + if (! b) + return LONG_MIN; + else { + int ayday = adjusted_yday(a, b); + int byday = adjusted_yday(b, a); + int days = ayday - byday; + long hours = a->tm_hour - b->tm_hour + 24 * days; + long minutes = a->tm_min - b->tm_min + 60 * hours; + long seconds = a->tm_sec - b->tm_sec + 60 * minutes; + return seconds; + } +#endif +} + static void show(timezone_t tz, char *zone, time_t t, bool v) { register struct tm * tmp; - struct tm tm; + register struct tm * gmtmp; + struct tm tm, gmtm; printf("%-*s ", longest, zone); if (v) { - tmp = my_gmtime_r(&t, &tm); - if (tmp == NULL) { + gmtmp = my_gmtime_r(&t, &gmtm); + if (gmtmp == NULL) { printf(tformat(), t); } else { - dumptime(tmp); + dumptime(gmtmp); printf(" UT"); } printf(" = "); @@ -874,10 +909,10 @@ show(timezone_t tz, char *zone, time_t t, bool v) if (*abbr(tmp) != '\0') printf(" %s", abbr(tmp)); if (v) { + long off = gmtoff(tmp, gmtmp); printf(" isdst=%d", tmp->tm_isdst); -#ifdef TM_GMTOFF - printf(" gmtoff=%ld", tmp->TM_GMTOFF); -#endif /* defined TM_GMTOFF */ + if (off != LONG_MIN) + printf(" gmtoff=%ld", off); } } printf("\n"); -- 1.9.3

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Thread Safety Notes
by Andy Heninger Sept. 22, 2014

Sept. 22, 2014

I've been looking over the thread safe additions to localtime.c, and have a few comments. 1. Use of C's 'volatile' declaration is not sufficient to implement fully thread-safe double-checked locking. The complications are confusing and subtle. Here is a paper that goes into the question in depth: http://www.aristeia.com/Papers/DDJ_Jul_Aug_2004_revised.pdf The bottom line is that doing it right needs memory barrier operations - a read acquire and write release or equivalent for the flag variable being tested. Volatile does not guarantee these. C11 has the necessary functions, but is not yet widely available. [ http://www.open-std.org/jtc1/sc22/WG14/www/docs/n1570.pdf ] Compilers mostly have non-standard extensions available that will do the job, often modeled after those in gcc. 2. The function gmtcheck() needs to recheck the gmt_is_set flag after acquiring the lock. As it stands, multiple threads could replicate the initialization, overwriting a previously set gmtptr in the process. This is unrelated to the volatile question. 3. The volatile variable lcl_is_set is referenced while not holding the lock in only one place, in localtime_r(). And from there the function localtime_tzset() is unconditionally called, which unconditionally acquires the lock. With minor refactoring, all access to lcl_is_set could be from code that is holding the lock, which would allow lcl_is_set to be an ordinary variable with no special thread safety considerations. If it were up to me, I would probably remove use of the double-checked idiom, and rely on solely lock(). Slightly slower, but simple, portable and safe. The alternative is to #define some compiler-dependent atomic operations. Thanks, -- Andy Heninger

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Europe/London Sat Oct 26 23:00:00 1968 UT
by "" Sept. 15, 2014

Sept. 15, 2014

Looks like isdst should be 1 on Europe/London Sat Oct 26 23:00:00 1968 and Europe/London Sun Oct 31 01:59:59 1971 zdump -v -c 1968,1973 Europe/London Europe/London -9223372036854775808 = NULL Europe/London -9223372036854689408 = NULL Europe/London Sun Feb 18 01:59:59 1968 UT = Sun Feb 18 01:59:59 1968 GMT isdst=0 gmtoff=0 Europe/London Sun Feb 18 02:00:00 1968 UT = Sun Feb 18 03:00:00 1968 BST isdst=1 gmtoff=3600 Europe/London Sat Oct 26 22:59:59 1968 UT = Sat Oct 26 23:59:59 1968 BST isdst=1 gmtoff=3600 Europe/London Sat Oct 26 23:00:00 1968 UT = Sun Oct 27 00:00:00 1968 BST isdst=0 gmtoff=3600 Europe/London Sun Oct 31 01:59:59 1971 UT = Sun Oct 31 02:59:59 1971 BST isdst=0 gmtoff=3600 Europe/London Sun Oct 31 02:00:00 1971 UT = Sun Oct 31 02:00:00 1971 GMT isdst=0 gmtoff=0 Europe/London Sun Mar 19 01:59:59 1972 UT = Sun Mar 19 01:59:59 1972 GMT isdst=0 gmtoff=0 Europe/London Sun Mar 19 02:00:00 1972 UT = Sun Mar 19 03:00:00 1972 BST isdst=1 gmtoff=3600 Europe/London Sun Oct 29 01:59:59 1972 UT = Sun Oct 29 02:59:59 1972 BST isdst=1 gmtoff=3600 Europe/London Sun Oct 29 02:00:00 1972 UT = Sun Oct 29 02:00:00 1972 GMT isdst=0 gmtoff=0 Europe/London 9223372036854689407 = NULL Europe/London 9223372036854775807 = NULL

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Typo in africa timezone file
by Marcel Telka Sept. 11, 2014

Sept. 11, 2014

In https://www.ietf.org/timezones/data/africa I found the following lines: # From Gunther Vermier (2015-05-13): # our Egypt office confirms that the change will be at 15 May "midnight" (24:00) I think the timestamp (2015-05-13) is not correct there. Should it say 2014-05-13 instead? -- +-------------------------------------------+ | Marcel Telka e-mail: marcel(a)telka.sk | | homepage: http://telka.sk/ | | jabber: marcel(a)jabber.sk | +-------------------------------------------+

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Regarding Russian Time zone change
by Peddi, Radhika (Radhika) Sept. 9, 2014

Sept. 9, 2014

Hi, I have taken latest tzdata tar and replaced Europe time zone in my joda. However I didn't find any changes in October 26 UTC Off string. Can you please tell me whether the changes are included in tzdata or not? Thanks & Regards, Radhika Peddi|Avaya India Pvt. Ltd.| Wing 'A', Level -5, Tower-11, Cybercity, Magarpatta City, Hadapsar | Pune, 411028|India Voice +91 20 4101 8311| Email: rpeddi<mailto:rpeddi@avaya.com>@avaya.com [Please consider the environment before printing this email]|7 Switch off POWER |[cid:image008.jpg@01CD293C.65903AA0] Save Water |q RECYCLE |P PRESERVE trees |

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valgrind errors loading UTC
by Richter, Jörg Sept. 8, 2014

Sept. 8, 2014

When loading ‚UTC‘ the function tzload seems to use an uninitialized value here: localtime.c:574: for (i = 0; i < sp->typecnt; ++i) if (sp->types[i] == 0) // <- sp->types[0] is uninitialized (sp->typecnt is 1) break; It might be a user error on my side. But I am unable to spot it. Note that the UTC file was generated with an older version. This is with tzcode2014g - Jörg

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[PROPOSED PATCH] * Makefile (check_sorted): Further improve quality of checks.
by Paul Eggert Sept. 7, 2014

Sept. 7, 2014

* NEWS: Document this. * zone1970.tab: Sort country codes better. --- Makefile | 13 +++++++++---- NEWS | 4 ++++ zone1970.tab | 2 +- 3 files changed, 14 insertions(+), 5 deletions(-) diff --git a/Makefile b/Makefile index 86682ce..7bdd642 100644 --- a/Makefile +++ b/Makefile @@ -487,12 +487,17 @@ check_white_space: $(ENCHILADA) ! grep -n '[[:space:]]$$' $(ENCHILADA) ! grep -n "$$(printf '[\f\r\v]\n')" $(ENCHILADA) -check_sorted: backward backzone iso3166.tab zone1970.tab - $(AWK) '/^Link/ {print $$3}' backward | LC_ALL=C sort -c - $(AWK) '/^Zone/ {print $$2}' backzone | LC_ALL=C sort -c - $(AWK) '/^[^#]/ {print}' iso3166.tab | LC_ALL=C sort -c +CHECK_CC_LIST = { n = split($$1,a,/,/); for (i=2; i<=n; i++) print a[1], a[i]; } + +check_sorted: backward backzone iso3166.tab zone.tab zone1970.tab + $(AWK) '/^Link/ {print $$3}' backward | LC_ALL=C sort -cu + $(AWK) '/^Zone/ {print $$2}' backzone | LC_ALL=C sort -cu + $(AWK) '/^[^#]/ {print $$1}' iso3166.tab | LC_ALL=C sort -cu + $(AWK) '/^[^#]/ {print $$1}' zone.tab | LC_ALL=C sort -c $(AWK) '/^[^#]/ {print substr($$0, 1, 2)}' zone1970.tab | \ LC_ALL=C sort -c + $(AWK) '/^[^#]/ $(CHECK_CC_LIST)' zone1970.tab | \ + LC_ALL=C sort -cu check_tables: checktab.awk $(PRIMARY_YDATA) $(ZONETABLES) for tab in $(ZONETABLES); do \ diff --git a/NEWS b/NEWS index 0f3c809..3134648 100644 --- a/NEWS +++ b/NEWS @@ -23,6 +23,10 @@ Unreleased, experimental changes An access to uninitalized data has been fixed. (Thanks to Jörg Richter for reporting the problem.) + Changes affecting build procedure + + 'make check' now checks better for properly-sorted data. + Changes affecting documentation and commentary zdump -c's treatment of years is now documented to use the diff --git a/zone1970.tab b/zone1970.tab index 03c50d8..f0e38f1 100644 --- a/zone1970.tab +++ b/zone1970.tab @@ -323,7 +323,7 @@ TM +3757+05823 Asia/Ashgabat TN +3648+01011 Africa/Tunis TO -2110-17510 Pacific/Tongatapu TR +4101+02858 Europe/Istanbul -TT,AG,AI,BL,DM,GD,GP,MF,LC,KN,MS,VC,VG,VI +1039-06131 America/Port_of_Spain +TT,AG,AI,BL,DM,GD,GP,KN,LC,MF,MS,VC,VG,VI +1039-06131 America/Port_of_Spain TV -0831+17913 Pacific/Funafuti TW +2503+12130 Asia/Taipei UA +5026+03031 Europe/Kiev most locations -- 1.9.1

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[PROPOSED PATCH 1/2] * Makefile (check_sorted): Fix typo in recent change.
by Paul Eggert Sept. 7, 2014

Sept. 7, 2014

--- Makefile | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) diff --git a/Makefile b/Makefile index 8e0a6d7..86682ce 100644 --- a/Makefile +++ b/Makefile @@ -491,7 +491,7 @@ check_sorted: backward backzone iso3166.tab zone1970.tab $(AWK) '/^Link/ {print $$3}' backward | LC_ALL=C sort -c $(AWK) '/^Zone/ {print $$2}' backzone | LC_ALL=C sort -c $(AWK) '/^[^#]/ {print}' iso3166.tab | LC_ALL=C sort -c - $(AWK) '/^[^#]/ {print substr($0, 1, 2)}' zone1970.tab | \ + $(AWK) '/^[^#]/ {print substr($$0, 1, 2)}' zone1970.tab | \ LC_ALL=C sort -c check_tables: checktab.awk $(PRIMARY_YDATA) $(ZONETABLES) -- 1.9.1

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