- tz - lists.iana.org

source code question regarding localtime.c PS
by Alois Treindl Aug. 8, 2013

Aug. 8, 2013

In localtime.c, function localsub() are these three lines of code: 1295 icycles = tcycles; 1296 if (tcycles - icycles >= 1 || icycles - tcycles >= 1) 1297 return NULL; I do not understand the reason why lines 1296 and 1297 exist. icycles and tcycles are equal. Their difference is always zero. Why test for it being not zero? PS: the reason why I am asking: I try to understand the source code of zdump.c It calls localtime() frequently, and has some cryptic code which depends on whether localtime() returned NULL. Therefore, I try to understand the conditions under which localtime() returns NULL. If that would be documented somewhee (I may have overlooked it), it would be great, as it is rather hard to understand it out of the terse code.

6 10

source code question regarding localtime.c
by Alois Treindl Aug. 7, 2013

Aug. 7, 2013

In localtime.c, function localsub() are these three lines of code: 1295 icycles = tcycles; 1296 if (tcycles - icycles >= 1 || icycles - tcycles >= 1) 1297 return NULL; I do not understand the reason why lines 1296 and 1297 exist. icycles and tcycles are equal. Their difference is always zero. Why test for it being not zero?

1 0

Timezone in Suse?
by Donald MacQueen Aug. 1, 2013

Aug. 1, 2013

Does anyone know where the currently selected system time zone in stored on Suse? I thought it was in /etc/localtime, but apparently not. Perhaps I need to call a c routine and ask the system? Thanks in advance. -- Donald [|] Joel Cairo: "You always have a very smooth explanation." Sam Spade: "What do you want me to do? Learn to stutter?" - The Maltese Falcom

2 2

localtime.c issue
by Andy Heninger July 21, 2013

July 21, 2013

This compilation error from the localtime.c in 2013d looks like an actual problem. I think time_t is generally an integer type of some sort. Built using the clang compiler on Linux. localtime.c:1517:34: error: implicit conversion from 'double' to 'time_t' (aka 'long') changes value from 0.5 to 0 [-Werror,-Wliteral-conversion] register time_t half_second = 0.5; ~~~~~~~~~~~ ^~~ 1 error generated. Thanks, -- Andy Heninger

10 20

Re: [tz] tz Digest, Vol 22, Issue 13
by ruggety＠ovi.com July 20, 2013

July 20, 2013

Why the change? ---------- Sent from my Nokia phone ------Original message------ From: <tz-request(a)iana.org> To: <tz(a)iana.org> Date: Tuesday, July 16, 2013 12:00:03 PM GMT+0000 Subject: tz Digest, Vol 22, Issue 13 Send tz mailing list submissions to tz(a)iana.org To subscribe or unsubscribe via the World Wide Web, visit https://mm.icann.org/mailman/listinfo/tz or, via email, send a message with subject or body 'help' to tz-request(a)iana.org You can reach the person managing the list at tz-owner(a)iana.org When replying, please edit your Subject line so it is more specific than "Re: Contents of tz digest..." Today's Topics: 1. Day length in the news (Arthur David Olson) 2. Saving electricity via horizontal time zones (Paul Eggert) ---------------------------------------------------------------------- Message: 1 Date: Mon, 15 Jul 2013 16:42:33 -0400 From: Arthur David Olson <arthurdavidolson(a)gmail.com> To: "tz(a)iana.org" <tz(a)iana.org> Subject: [tz] Day length in the news Message-ID: <CAJvZEYkKfJOnvs=ZbaHv6sVCDa+kQ4fTFbF+aYe4DfCFOKgJBw(a)mail.gmail.com> Content-Type: text/plain; charset="iso-8859-1" (Probably of marginal interest to most folks on the list.) >From the on-line Washington Post: "Stutters in Earth's spin changed length of days slightly" http://www.washingtonpost.com/national/health-science/stutters-in-earths-sp… The Post article stems from R. Holme & O. de Viron, "Characterization and implications of intradecadal variations in length of day," Nature 499, 202-204 (11 July 2013); http://www.nature.com/nature/journal/v499/n7457/full/nature12282.html (only abstract is available for free). --ado

1 0

Informing ICANN about IANA time zone database status of Jerusalem
by Tobias Conradi July 17, 2013

July 17, 2013

---------- Forwarded message ---------- From: ICANN <do-not-reply(a)icann.org> Date: Sat, May 4, 2013 at 7:34 PM Subject: Form submission confirmation To: ...(a)tobiasconradi.com This is a copy for your records: Submitted on 4 May 2013 Submitted by user: Submitted values are: First Name: Last Name: Email Address: ...(a)tobiasconradi.com Affiliation: Country of Current Residence: Germany Please Select a Category: General - for general questions and comments Subject: ICANN vs UN and international practice - Status of Jerusalem Message: ICANN puts Jerusalem as Israel territory. The issue has been posted to the IANA time zone mailing list, but the maintainer did not reply. http://mm.icann.org/pipermail/tz/2013-April/019134.html http://mm.icann.org/pipermail/tz/2013-May/019227.html -- Tobias Conradi Rheinsberger Str. 18 10115 Berlin Germany http://tobiasconradi.com

9 11

Re: [tz] Number of active tz regions?
by David Patte ₯ July 17, 2013

July 17, 2013

Thank you all. This is what I understood as well. On 2013-07-17 13:32, Tim Parenti wrote: > > On 17 July 2013 12:53, David Patte ₯ <dpatte(a)relativedata.com > <mailto:dpatte@relativedata.com>> wrote: > > Am I correct to say, that for every lat/lng there (theoretically) > exists a zone in that country and/or region that represents its > timezone rules since 1970; that if no tz zone exists in that > country and/or region that represents it clock rules since 1970 > correctly, that a new zone is to be created in tz for it? > > > In theory, yes, that is my understanding. Of course, in international > waters, the zone that "correctly" represents the local rules would be, > e.g., Etc/GMT-3, but in general, if an existing set of rules does not > properly cover a region (for all timepoints since 1970), a new zone is > to be created. > > On 17 July 2013 12:53, David Patte ₯ <dpatte(a)relativedata.com > <mailto:dpatte@relativedata.com>> wrote: > > I am looking at this from the perspective of timezone boundaries; > that tz boundaries (theoretically) don't change unless new tz > zones are created, or it is discovered that a latlng's clock > 'rules' since 1970 can be more accurately be described by a > different tz zone? > > > The tz project neither defines nor tracks zone boundaries; however, it > is sometimes helpful to think of zones in this manner. Obviously such > boundaries would change upon the creation of a new zone. You could > make the case that such boundaries would also change if it is > discovered at some point that location A better matches zone X than > zone Y, but as long as location A is not itself defined in zone.tab, > this does not affect tz data, and thus does not concern the tz project > beyond documenting appropriate commentary. > > -- > Tim Parenti --

1 0

Saving electricity via horizontal time zones
by Paul Eggert July 15, 2013

July 15, 2013

A recent paper by Felix Weinhardt of the Spatial Economics Research Centre of the London School of Economics and Political Science argues that daylight saving time increases electricity use in the northern part of the U.S., but decreases its use in the south. Weinhardt proposes horizontal time zones to ameliorate this, and estimates that their use would save the U.S. about 0.1% of its total GDP. Weinhardt F. The importance of time zone assignment: evidence from residential electricity consumption. SERC Discussion Paper 126 (January 2013). http://www.lse.ac.uk/GranthamInstitute/events/docs/The-importance-of-time-z…

1 0

Day length in the news
by Arthur David Olson July 15, 2013

July 15, 2013

(Probably of marginal interest to most folks on the list.) >From the on-line Washington Post: "Stutters in Earth's spin changed length of days slightly" http://www.washingtonpost.com/national/health-science/stutters-in-earths-sp… The Post article stems from R. Holme & O. de Viron, "Characterization and implications of intradecadal variations in length of day," Nature 499, 202-204 (11 July 2013); http://www.nature.com/nature/journal/v499/n7457/full/nature12282.html (only abstract is available for free). --ado

1 0

400-year-repeat edge cases
by Zefram July 14, 2013

July 14, 2013

The attached patch tweaks zic's explicit-400-years hack to better handle some edge cases. It's based on current github source. -zefram

1 0