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Kuwait considers DST
by Matt Johnson Aug. 9, 2016

Aug. 9, 2016

Apparently Kuwait is considering introducing DST next year. It has never done so before. I can't find a more official reference at the moment, but worth keeping an eye on: https://twitter.com/jahrawie/status/762362762760744961 Any Arabic native speakers able to read the text in the images? If so, a summary would be appreciated. Thanks, Matt

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New leap second
by Meno Hochschild Aug. 8, 2016

Aug. 8, 2016

Dear users of tzdb, IERS has announced a new leap second at the end of year 2016, see https://hpiers.obspm.fr/iers/bul/bulc/bulletinc.dat Another point: I have myself written a time library in Java called Time4J which contains a tz compiler based on your data and which also evaluates the leap second file contained in tz-data. Hence this library could be listed in the file "tz-link" within the section "Other tz compilers" maybe with this description: <a href="https://github.com/MenoData/Time4J/">Time4J – Advanced date, time and interval library for Java</a> , uses the class <code>net.time4j.tool.TimezoneRepositoryCompiler.java</code> located in TZTool-module that compiles <code><abbr>tz</abbr></code> source into a Time4J-specific binary format. Time4J is available under a LGPLv2.1-licence. Cheers and thanks for your very useful work Meno

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POSIX-TZ-environment-variable-style string rules
by Alexander Belopolsky Aug. 5, 2016

Aug. 5, 2016

The tzfile.5 manual page describes the TZ string found at the end of the version 2+ tzfiles as follows: "After the second header and data comes a newline-enclosed, POSIX-TZ-environment-variable-style string for use in handling instants after the last transition time stored in the file." Consider the case when the last transition time (T) stored in the file comes a few weeks before the first POSIX rule transition P > T. What local time type should be used for the the times after T, but before P? The strict reading of the manual page suggests that one should use the the local time type derived from the POSIX rule for all times t >= T, but it would be more reasonable to continue using the type that corresponds to T for times T <= t < P. It turns out the two alternative logics are implemented in real life. The glibc library switches [1] to the POSIX rule when t >= P, while the tzcode implementation uses POSIX rule to supply additional transitions with the first POSIX-derived transition at P. This leads to a discrepancy between glibc and tzcode results that is best described on the Ubuntu bug tracker (bug #1587128 [2]). While tzcode behavior is more logical, glibc code seems to better match the documentation and it will probably be an uphill battle to get a fix into glibc. [3] I think a better solution would be to make zic add a redundant transition when the local time type corresponding to the last transition does not match the POSIX rule. This will ensure that tzcode and glibc produces the same results and systems affected by this issue can be fixed by simply upgrading the zoneinfo database. [1]: https://sourceware.org/git/?p=glibc.git;a=blob;f=time/tzfile.c;h=9049878399… [2]: https://bugs.launchpad.net/ubuntu/+source/glibc/+bug/1587128 [3]: https://sourceware.org/ml/libc-help/2016-04/msg00000.html

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Morocco DST change happened on 4/June/2016 instead of 5/June/2016
by Gopal . Aug. 4, 2016

Aug. 4, 2016

Hi Team, TZupdater updated time zone 1 day before scheduled time, it was supposed to change time on 5 June 2016 for Morocco Casablanca and but application time changed on 4 June 2016. Could you please let us know as we are facing some problems in application due to this. Regards Gopal This e-mail and all material transmitted with it are for the use of the intended recipient(s) ONLY and contains confidential and/or privileged information. If you are not the intended recipient, please contact the sender by reply e-mail and destroy all copies and the original message. Any unauthorized review, use, disclosure, dissemination, forwarding, printing or copying of this email or any action taken pursuant to the contents of the present e-mail is strictly prohibited and is unlawful. The recipient acknowledges that Comviva Technologies Limited or its management or directors, are unable to exercise control or ensure the integrity over /of the contents of the information contained in e-mail. Any views expressed herein are those of the individual sender only and no binding nature of the contents shall be implied or assumed unless the sender does so expressly with due authority of Comviva Technologies Limited. E-mail and any contents transmitted with it are prone to viruses and related defects despite all efforts to avoid such by Comviva Technologies Limited.

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Regarding IANA update for Novosibirsk Time Zone
by Shruthi Venkataramanan -X (shruthve - WIPRO LIMITED at Cisco) Aug. 2, 2016

Aug. 2, 2016

Hi Iana Team, We have already requested for an update regarding Novosibirsk Time Zone , please find the email chain attached. Currently we want to know, when can you give us an updated Version, so that we can do the changes in our software. Thanks & Regards, Shruthi.

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why does mktime binary search?
by enh July 29, 2016

July 29, 2016

is there a more detailed explanation of why mktime does binary search? ** Adapted from code provided by Robert Elz, who writes: ** The "best" way to do mktime I think is based on an idea of Bob ** Kridle's (so its said...) from a long time ago. ** It does a binary search of the time_t space. Since time_t's are ** just 32 bits, its a max of 32 iterations (even at 64 bits it ** would still be very reasonable). this came up on Android because we had some code that did "errno = 0; mktime(...); if (errno == EOVERFLOW) ..." rather than checking the return value of mktime. this failed for us because the tzcode mktime sets errno even on non-failure. obviously i can fix this by saving errno around the call to mktime_tzname in mktime, but i'm curious to know why there's a binary search at all. i also notice that, of the BSDs, NetBSD seems to have fixed this locally, FreeBSD has an old enough copy of tzcode that it's not setting errno at all, and OpenBSD is in the same boat as Android. here's the NetBSD change, which is does the errno save-restore in time1 instead: revision 1.90 date: 2014-10-16 10:53:32 -0700; author: christos; state: Exp; lines: +24 -36; commitid: 4woGqYWkKe0i6sUx; - don't leak errno in mktime() - when we load a new timezone, don't change anything unless the load succeeded. http://cvsweb.netbsd.org/bsdweb.cgi/src/lib/libc/time/localtime.c.diff?r1=1…

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Public Key Wanted
by Peter Remmers July 29, 2016

July 29, 2016

Hello, I've been trying to find the public key that was used to sign the tzdata and tzcode files on ftp.iana.org/tz. I found this: https://mm.icann.org/pipermail/tz/2014-June/020967.html which says the key ID is 62AA7E34, but it's not. gpg -vv tzdata-latest.tar.gz.asc says the files were signed using key ID 043DB63744AD418C (or short 44AD418C), but this key isn't to be found on any keyserver I tried. I kindly request a pointer to the public key that was used for the current files on the ftp server, so we can verify the signatures. Regards, Peter Remmers

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Request regarding IANA update for Novosibirsk Time Zone
by Shruthi Venkataramanan -X (shruthve - WIPRO LIMITED at Cisco) July 28, 2016

July 28, 2016

Hi, Novosibirsk Oblast moved forward one hour from UTC+06:00 to UTC+07:00 (from Omsk to Krasnoyarsk time). This time zone change occurred on 24 July 2016. When can we expect the updated version of IANA Time Zone Data. Thanks & Regards, Shruthi.

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Blog Post: On the Timing of Time Zone Changes
by Matt Johnson July 26, 2016

July 26, 2016

I've written a blog post describing the chaos that ensues when governments don't provide enough notice of their changes to time zones. http://codeofmatt.com/2016/04/23/on-the-timing-of-time-zone-changes/ <http://aka.ms/weboutlook> Enjoy! -Matt

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ICANN contacts Egyptian government about recent last-minute clock change
by Paul Eggert July 24, 2016

July 24, 2016

Baher Esmat of ICANN contacted the Egyptian government asking it to give us more notice about clock changes next time. This found its way into the popular press earlier this month; here's the English-language version: Al-Youm A-M. ICANN thrown into confusion by cancelation of Daylight Saving Time. Egypt Independent 2016-07-08. http://www.egyptindependent.com/news/icann-thrown-confusion-cancelation-day…

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