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FW: Does zic currently compile time zone abbreviations correctly?
by Olson, Arthur David (NIH/NCI) [E] July 27, 2007

July 27, 2007

I'm forwarding this message from John B. Morrow, who is not on the time zone mailing list. Those of you who are on the time zone mailing list should direct replies appropriately. --ado From: John B. Morrow [mailto:jmorrow@sendwordnow.com] Sent: Friday, July 27, 2007 2:29 AM To: tz(a)lecserver.nci.nih.gov Subject: Does zic currently compile time zone abbreviations correctly? In the process of extracting time zone information from the zoneinfo database, I noticed that the abbreviation pointer break for quite a few time zones including Europe/London, Asia/Dubai, and quite a few others. The problem seems to be in the compiled time zone files so I spent some time looking at zic. What seems to be happening is that zic uses some criteria to determine of the abbreviation (and other info for types) is used and won't write it if it thinks it isn't needed. The problem is that it doesn't adjust the indexes (tt_abbrind) that reference those abbreviations, so they'll point to bad data or empty strings. My quick (and admittedly heavy handed fix) was to force zic to write all of the abbreviations, whether they are necessary or not. If this really is a problem, it should probably be fixed at some point. Please note that the data in our fairly recently updated Linux server has abbreviations that don't seem to work. If I'm missing something or there is some other way more correct way to reference the abbreviations, please let me know. I'm using tt_abbrind as per the tzfile man page and the tzcode2007f.tar.gz sources. John Morrow

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Does zic currently compile time zone abbreviations correctly?
by John B. Morrow July 27, 2007

July 27, 2007

In the process of extracting time zone information from the zoneinfo database, I noticed that the abbreviation pointer break for quite a few time zones including Europe/London, Asia/Dubai, and quite a few others. The problem seems to be in the compiled time zone files so I spent some time looking at zic. What seems to be happening is that zic uses some criteria to determine of the abbreviation (and other info for types) is used and won't write it if it thinks it isn't needed. The problem is that it doesn't adjust the indexes (tt_abbrind) that reference those abbreviations, so they'll point to bad data or empty strings. My quick (and admittedly heavy handed fix) was to force zic to write all of the abbreviations, whether they are necessary or not. If this really is a problem, it should probably be fixed at some point. Please note that the data in our fairly recently updated Linux server has abbreviations that don't seem to work. If I'm missing something or there is some other way more correct way to reference the abbreviations, please let me know. I'm using tt_abbrind as per the tzfile man page and the tzcode2007f.tar.gz sources. John Morrow

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How to support such capabilites based on current Olson Time Zone implementation
by Martin Dong July 27, 2007

July 27, 2007

Dear All in this maillist, We have been investigating the feasibility of migrating Olson Time Zone Database to our system. Given that our system is Linux-based, we can just use tzcode implementation or Glibc functions because Glibc has adopted Olson implementation to some extent. But according to our basic and existing requirements, I have met some problems that I think are hard for me: - How to get the local time of different region or city at the same time? The basic requirement is to display the local time of different region or city at the same time. After some study of Olson implementation, I knew function "localtime" will handle everything, parsing tzfile and doing the conversion from utc to local time. The correct local time can be gotten through a simple invocation to "localtime". But "localtime" assumes the Sytem Local Time Zone is set in environmental variable "TZ" or from the Standard TimeZone file "/etc/localtime" if "TZ" is not defined in the process. In this case, how can a caller get the local time of some city which is not the System Local Time Zone? It seems we must change "TZ" or the Standard TimeZone file before calling "localtime" to get another city's local time because "localtime" doesn't take such an argument that can let caller specify a time zone, which means "localtime" can return the local time related to either the System Local Time Zone or the time zone user specifies. Although I know there're so many applications which already integrates the Olson Database and they have realized my above requirement "display multiple local time at the same time", I don't know how they make it. - How to get the notification of DST status change as time elaspes? This problem is out of our another requirement that we need to inform other components in our system of the DST status change in various conditions, such as changing time may lead to DST change, changing local time zone may lead to DST change, and as time elapsing, etc. The former two behaviors are user-active ones, we can track the change easily, but the problem is the last one, it's the system automatic behavior, our of the control of user. In this case, the system needs some CALLBACK ability to capture this change and further broadcast it. For our system, there's an Alarm Server that can provide timer machinasm. We will parse our own time zone database and get the next nearest DST transition time and add it to Alarm Server, then when the timer is time out, Alarm Server will trigger a CALLBACK function to further process. But it seems Olson is lack of such capability. After thinking from another perpsective, if we can get the next nearest DST transition time through Olson Time Zone database, we can still utilize our current Alarm Server. But it's still a problem how to get the next nearest DST transition time through the current Olson implementation because all the implementation is hiden behind "localtime". In all the public functions, there's no such one which can support getting the DST transition time. I don't have any good idea in mind right now. Should I make some modification to Olson to add such capability, or other way i could go? I will very much appreciate if any of you can give me some hints about above problems. Thank you in advance. Best Regards, -Martin

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FW: Timezone of America/Tegucigalpa is wrong
by Olson, Arthur David (NIH/NCI) [E] July 23, 2007

July 23, 2007

I'm forwarding this message from Freek de Kruijf, who was not on the time zone mailing list at the time it was sent. Freek has since been added. --ado -----Original Message----- From: Freek de Kruijf [mailto:f.de.kruijf@hetnet.nl] Sent: Sunday, July 22, 2007 3:38 To: tz(a)lecserver.nci.nih.gov Subject: Timezone of America/Tegucigalpa is wrong L.S. The timezone of America/Tegucigalpa includes a Daylight Saving Time. This is wrong. See http://en.wikipedia.org/wiki/Honduras . It is only UTC-6. I can confirm this, while I am there. -- fr.gr. Freek de Kruijf

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Olson tz database tests
by Kevin July 23, 2007

July 23, 2007

Hi, is there an existing suite of tests (e.g. unit tests, regression tests, etc.) for the Olson time zone database (to ensure validity, completeness, etc.)? I'm more interested in the logic than the language, although I would prefer C/C++, C#, or Java. Thanks, Kevin

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More daylight savings in Australia
by Eric Ulevik July 23, 2007

July 23, 2007

The states of NSW, Victoria, ACT, Tasmania plan to harmonize DST, starting October 2007. "Under the plan, clocks will go forward one hour on the first Sunday in October, instead of on the last Sunday, and will be wound back by an hour on the first Sunday in April, rather than on the last Sunday in March." http://www.news.com.au/story/0,23599,21549128-2,00.html Regards, Eric Ulevik

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Timezone of America/Tegucigalpa is wrong
by Freek de Kruijf July 22, 2007

July 22, 2007

L.S. The timezone of America/Tegucigalpa includes a Daylight Saving Time. This is wrong. See http://en.wikipedia.org/wiki/Honduras . It is only UTC-6. I can confirm this, while I am there. -- fr.gr. Freek de Kruijf

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Re: Geographical boundaries for the continental US tz zones
by rlaw＠nc.rr.com July 18, 2007

July 18, 2007

----- Original Message ----- From: Paul Eggert <eggert(a)CS.UCLA.EDU> > I send my comments to your US timezone map directly to the TZ list > since I > think it could be of common interest in the list and also to urge > members to > send comments where appropriate. I've put all of my findings about the limits of U.S. time zones (past and present) online at http://www.statoids.com/tus.html. It's all verbal description. For example: > * Idaho county split (Idaho state) > I have a northern and southern part of Idaho county, which I got from > another timezone map (possibly Manifold map). This indicates that the > southern part of Idaho county is on America/Boise time while the > northernpart is on America/Los_Angeles. I have "Idaho county north of the Salmon River" on Pacific Time. > * Sioux county North Dakota > Tz database states "part of Sioux county" and that is exactly what > you have > included, splitting it around Latitude 46 Longitude -101.34. Where > did you > get shis from? I have included all Sioux county being on same time, > but that > most be wrong. I have "Sioux county west of ND route 31" on Mountain Time. Gwillim Law

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Daviess, Dubois, Knox, Martin and Pike counties jump thru 1 more hoop
by Paul Eggert July 18, 2007

July 18, 2007

The DOT yesterday announced a proposed rule that would move the 132,000 residents of Daviess, Dubois, Knox, Martin and Pike counties in Indiana back to Eastern time, effective November 4 (when DST ends this year). The proposed rule has a 30-day public comment period, and then must be approved by the DOT to become final. See the AP article on this subject at <http://www.indystar.com/apps/pbcs.dll/article?AID=/20070718/LOCAL/707180456…>.

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FW: Implementation of zoneinfo (Olson, tz) database in .NET c-sharp csharp
by Olson, Arthur David (NIH/NCI) [E] July 18, 2007

July 18, 2007

I'm forwarding this message from Joshua Kifer, who is not on the time zone mailing list. Those of you who are on the time zone mailing list should direct replies appropriately. --ado From: Joshua Kifer [mailto:joshua@jotts.com] Sent: Wednesday, June 20, 2007 8:33 PM To: tz(a)lecserver.nci.nih.gov Subject: Implementation of zoneinfo (Olson, tz) database in .NET c-sharp csharp I finally found an implementation of this at CodePlex. It's part of the PublicDomain project. http://www.codeplex.com/publicdomain I hope this post adds some search fodder to the interweb for all those unlucky bastards seeking (and not finding) the same.

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