- tz - lists.iana.org

Time zones in the Global Gazetteer
by alan＠allm-geodata.com Feb. 1, 2001

Feb. 1, 2001

members of this list may be interested in the following extract from a recent newsletter that I sent out: <snip> TIME ZONES I have now included canonical time zone names in the Global Gazetteer. The canonical name (e.g. America/New_York) is then the key to time zone offset from GMT, and also the daylight saving time rules (date and time on and off), using the tztab format. There are still some gaps, most notably where the rule for assigning the name cuts across established administrative boundaries and also where I do not yet know the province and/or lower administrative areas within which the place falls. I am currently carrying out research to resolve these problems, but about 90% of records (including 'trains and boats and planes') now have canonical names assigned. Changes to zones and DST are regularly monitored and the records updated. There is a short paper on the web site that explains this in a bit more detail, describes all the various fields that are available, and explains the tztab format for DST rules. Other formats can be output if required. <end snip> I am not attempting to hold the wealth of historical data that the tz database holds. I am only interested in the current and future situation. There are two major problems that I am tackling: 1. the rather generic descriptions that are sometimes used in the tz data and trying to match these to my hierarchy of country/province/lower level admin area/town. For example 'far western Texas' or 'eastern Lugansk'. I am trying to clarify these where possible and will report back, if I find any useful information. 2. Completing the data that is in the Global Gazetteer, so that I can use the tz rules. This especially applies to countries such as Indonesia where many places do not yet have province name assigned, or in trying to find out which settlements fall within the county of Yancowinna in Australia Best wishes Alan Pritchard The GLOBAL GAZETTEER: the world on file http://www.allm-geodata.com Tel: +44 (0) 1202 417 477

1 0

XBDd4 - tzset
by Garrett Wollman Jan. 31, 2001

Jan. 31, 2001

<<On Wed, 31 Jan 2001 12:34:07 -0500, "Seeds, Glen" <Glen.Seeds(a)Cognos.COM> said: > First, the daylight saving offset is not specified. Yes, we all "know" it's > an hour (to be ADDED, in this case), but a standard needs to specify this. Actually, we don't know that. Several places have observed one-half or two-hour shifts in the past, and there is no guarantee that the politicians will not come up with new ones in the future. An examination of the timezone database shows eighteen different locations where this has been done, of which one (Lord Howe Island) still uses a non-unity-hour summer-time adjustment. > It turns out that you can achieve all of this with mktime() and gmtime(). > Given that, perhaps a better strategy would be to guide applications toward > that, and away from tzset(). I agree, and I think the denizens of the timezone mailing-list (cc'ed) would probably agree as well. (Speaking as an implementor for a BSD-derived system that has never implemented and probably will never implement the `tzoffset' and `daylight' variables.) -GAWollman

1 0

Indiana considers DST (NYT)
by Markus Kuhn Jan. 31, 2001

Jan. 31, 2001

Indiana Considers Synchronizing Its Watches, by PAM BELLUCK. The New York Times, 2001-01-31. http://www.nytimes.com/2001/01/31/national/31TIME.html?pagewanted=all Markus -- Markus G. Kuhn, Computer Laboratory, University of Cambridge, UK Email: mkuhn at acm.org, WWW: <http://www.cl.cam.ac.uk/~mgk25/>

1 0

FW: quality of historical zone information
by Olson, Arthur David (NCI) Jan. 29, 2001

Jan. 29, 2001

Alois Treindl is not on the time zone mailing list; direct replies appropriately. --ado -----Original Message----- From: Alois Treindl [mailto:alois@astro.ch] Sent: Sunday, January 28, 2001 11:11 AM To: tz(a)elsie.nci.nih.gov Subject: quality of historical zone information Hi my company is an astrological computer service, and as you certainly know, astrologers are the only group of people for whom precise timezone information for any place, and any historical time is really essential. This is also why Thomas Shanks had created the International and American atlas. Tom is long gone from ACS, and they no longer maintain their database properly. Your site has become the essential source on timezone information. However, for historical work your data are insufficient in many areas. For example in Germany, there must be about 20 zones differentiated which have had a different timezoen history since the introduction of standard time. Th tz database has only a single zone info for Germany. For many other countries the same is true, e.g. for France, where there is a complicated historical pattern, especially during the years of the World War II and german occupation. Many US states have a very complex timezone history, and for some states several hundreds of 'zones' will be needed to reflect these data precisely. Defining more zones will not be enough. it must be possible to associate every populated place with the right zone. For example in the case of Germany, each village or city must be associated with one of the zones. Current organisational units, like districts or 'Laender' are not sufficient for that, because some towns have changed this association occasionally in the past, i.e. have changed the 'land' or disctrict to which they belong. I would like to see the tz-database become THE reference source for this kind of information, but it is a long path of work. I might be able to contribute to this efffort, particularily after my scheduled retirement in mid-2002. I would like to know whether there are any plans of a systematic nature to improve the quality of historical work in the TZ database. Best regards || Alois Treindl, Astrodienst AG, mailto:alois@astro.com || Zollikon/Zurich, Switzerland || Free astrological charts at http://www.astro.com/ || SWISS EPHEMERIS Free Edition at http://www.astro.com/swisseph/

7 7

quality of historical zone information
by Alois Treindl Jan. 28, 2001

Jan. 28, 2001

Hi my company is an astrological computer service, and as you certainly know, astrologers are the only group of people for whom precise timezone information for any place, and any historical time is really essential. This is also why Thomas Shanks had created the International and American atlas. Tom is long gone from ACS, and they no longer maintain their database properly. Your site has become the essential source on timezone information. However, for historical work your data are insufficient in many areas. For example in Germany, there must be about 20 zones differentiated which have had a different timezoen history since the introduction of standard time. Th tz database has only a single zone info for Germany. For many other countries the same is true, e.g. for France, where there is a complicated historical pattern, especially during the years of the World War II and german occupation. Many US states have a very complex timezone history, and for some states several hundreds of 'zones' will be needed to reflect these data precisely. Defining more zones will not be enough. it must be possible to associate every populated place with the right zone. For example in the case of Germany, each village or city must be associated with one of the zones. Current organisational units, like districts or 'Laender' are not sufficient for that, because some towns have changed this association occasionally in the past, i.e. have changed the 'land' or disctrict to which they belong. I would like to see the tz-database become THE reference source for this kind of information, but it is a long path of work. I might be able to contribute to this efffort, particularily after my scheduled retirement in mid-2002. I would like to know whether there are any plans of a systematic nature to improve the quality of historical work in the TZ database. Best regards || Alois Treindl, Astrodienst AG, mailto:alois@astro.com || Zollikon/Zurich, Switzerland || Free astrological charts at http://www.astro.com/ || SWISS EPHEMERIS Free Edition at http://www.astro.com/swisseph/

1 0

Mexican time zones in the news.
by Olson, Arthur David (NCI) Jan. 25, 2001

Jan. 25, 2001

The 2001-01-24 traditional Washington Post contained the page one story "Timely Issue Divides Mexicans." An electronic version is available at http://www.washingtonpost.com/wp-dyn/articles/A37383-2001Jan23.html. For this mailing list, the heart of the matter is that Mexico City Mayor Lopez Obrador "...is threatening to keep Mexico City and its 20 million residents on a different time than the rest of the country..." In particular, Obrador would abolish observation of Daylight Saving Time. --ado

1 0

Linux timezone info
by billm＠cognito.co.uk Jan. 22, 2001

Jan. 22, 2001

Sir Do you still handle the timezone package for Linux. If so can you direct me to where I can get the latest version of this package ? Manmy thanks Regards Bill Melotti |-----------------------------------------------------------| | Senior Software Design Engineer Cognito Limited | | Tel 01635-508314 Block 4 | | Fax 01635-550783 Benham Valance | | Messager: #COG088 Newbury | | Berks | | RG20 8LU | | E-Mail: bill.melotti(a)cognito.co.uk | |-----------------------------------------------------------|

1 0

RE: New daylight saving period in Mexico
by Jesper Nørgaard Jan. 20, 2001

Jan. 20, 2001

Thanks to Gwillim Law for investigating this matter, and for the pretty accurate translation. I just have a small correction which doesn't change the general outcome. He writes: "In the specific case of Distrito Federal, he telephoned the government of Andrés Manuel López Obrador in order to ascertain his position. [The article doesn't report any conclusion reached in this matter.]" Actually it should be "he urged the government of Andrés Manuel López Obrador to reconsider its position". It is correct that there was no conclusion about that yet. Note that "llamado" here is not a telephone call, but rather a petition, or beckon or attracting attention. Another interesting article was http://www.reforma.com/nacional/articulo/064327/ which in general terms explains the opposition to the daylight saving by various groups in Oaxaca, for instance peasants, teachers and lawyers. But the clou is mentioning the measure the teachers take: "In Oaxaca, the 55.000 teachers from the Section 22 of the National Syndicate of Education Workers, refuse to apply daylight saving each year, so that the more than 10.000 schools work at normal hour the whole year." In other words, all the pupils and teachers of Oaxaca are on Central Standard Time all year round, even when the rest of the state is on Central Daylight Time. Should that be included in the Timezone list? Probably not, but an amusing little revolution it is, similar to the state of affairs in Nunavut at one point, with different offices in the same region having different hour. I have not found an official version of the presidential decree, but I assume that the exact hour that DST is starting and ending is the same as previous years, and indeed the same as for all the USA mainland daylight saving (there are exceptions in american Antarctica stations), e.g. starting at 2:00 Standard time, and ending 2:00 Daylight time. Regards, Jesper Nørgaard Welen Email: jnorgard(a)Prodigy.Net.mx Programador/Analista CIMMYT - Centro Internacional de Mejoramiento de Maíz y Trigo Dirección: CIMMYT Int. c/o Jesper Nørgaard Km. 45, Carretera México-Veracruz El Batán Texcoco, Edo. de México CP 56130 MEXICO Tel.: +52 (5) 58-04-20-04 ext. 1374 Fax: +52 (5) 58-04-75-58 Tel. Casa: 53-10-05-95 ó 53-10-97-78 CIMMYT home page: http://cimmyt.cgiar.org Check out my World Time Explorer: http://timezone50.homepage.com ---------- From: Gwillim Law[SMTP:gwil@mindspring.com] Sent: Viernes 19 de Enero de 2001 13:54 To: TZ Mailing list Subject: New daylight saving period in Mexico Jesper Nørgaard Welen wrote: > The decision is not yet taken, but according to these articles should be > taken within 2-3 days: The days have gone by, so I checked for more recent information at the same Web site. I found an article at <http://www.reforma.com/negocios_y_dinero/articulo/064481/> that says (translated): Mexico City, January 17, 2000 - The Energy Secretary, Ernesto Martens, announced that Summer Time will be reduced from seven to five months, starting this year. The measure, he said, is in response to the public demand to have one less hour of natural light during the mornings in the first and last month of summer time, in that the latter will begin on the first Sunday in May and will end on the last Sunday of September. This change in the period of application of summer time will entail a reduction of ten weeks in comparison to the original schedule, which envisioned setting the clock an hour ahead from April 1 to October 28. Beginning this year, Mexico will have Summer Time with a duration of 20 weeks. [...] Concerning the possibility that some states in the Republic, including Distrito Federal, may not apply summer time, the official said that in the past, some states decided not to apply the measure, and this caused distortions in relation to the rest of the country. In the specific case of Distrito Federal, he telephoned the government of Andrés Manuel López Obrador in order to ascertain his position. [The article doesn't report any conclusion reached in this matter.] Yours, Gwillim Law

1 0

New daylight saving period in Mexico?
by Jesper Nørgaard Welen Jan. 20, 2001

Jan. 20, 2001

According to the following information, we are about to get a decision here in Mexico whether the application of daylight saving will be 2 or 3 months shorter this year or not. The decision is not yet taken, but according to these articles should be taken within 2-3 days: http://www.reforma.com.mx/ciudad_de_mexico/articulo/063682/ http://www.reforma.com.mx/nacional/articulo/063665/ http://www.reforma.com.mx/nacional/articulo/063770/ Regards, Jesper Nørgaard Welen Email: jnorgard(a)Prodigy.Net.mx Programador/Analista CIMMYT - Centro Internacional de Mejoramiento de Maíz y Trigo Dirección: CIMMYT Int. c/o Jesper Nørgaard Km. 45, Carretera México-Veracruz El Batán Texcoco, Edo. de México CP 56130 MEXICO Tel.: +52 (5) 58-04-20-04 ext. 1374 Fax: +52 (5) 58-04-75-58 Tel. Casa: 53-10-05-95 ó 53-10-97-78 CIMMYT home page: http://cimmyt.cgiar.org Check out my World Time Explorer: http://timezone50.homepage.com

3 2

etcetera patch
by Semen A. Ustimenko Jan. 16, 2001

Jan. 16, 2001

Hi! I've discovered that definition for GMT+N anf GMT-N are just wrong. I.e. setting zone to GMT+6 you really get -6 hours offset from GMT. And this is quite correct as is defined in etcetera file! So, suppose follwoing patch worth commiting. Index: src/share/zoneinfo/etcetera =================================================================== RCS file: /usr/home/ncvs/src/share/zoneinfo/etcetera,v retrieving revision 1.1.2.4 diff -c -r1.1.2.4 etcetera *** src/share/zoneinfo/etcetera 1999/01/21 21:35:07 1.1.2.4 --- src/share/zoneinfo/etcetera 2000/12/04 15:14:56 *************** *** 37,65 **** # zic -l GMT-12 # so we moved the names into the Etc subdirectory. ! Zone Etc/GMT-14 14 - GMT-14 # 14 hours ahead of GMT ! Zone Etc/GMT-13 13 - GMT-13 ! Zone Etc/GMT-12 12 - GMT-12 ! Zone Etc/GMT-11 11 - GMT-11 ! Zone Etc/GMT-10 10 - GMT-10 ! Zone Etc/GMT-9 9 - GMT-9 ! Zone Etc/GMT-8 8 - GMT-8 ! Zone Etc/GMT-7 7 - GMT-7 ! Zone Etc/GMT-6 6 - GMT-6 ! Zone Etc/GMT-5 5 - GMT-5 ! Zone Etc/GMT-4 4 - GMT-4 ! Zone Etc/GMT-3 3 - GMT-3 ! Zone Etc/GMT-2 2 - GMT-2 ! Zone Etc/GMT-1 1 - GMT-1 ! Zone Etc/GMT+1 -1 - GMT+1 ! Zone Etc/GMT+2 -2 - GMT+2 ! Zone Etc/GMT+3 -3 - GMT+3 ! Zone Etc/GMT+4 -4 - GMT+4 ! Zone Etc/GMT+5 -5 - GMT+5 ! Zone Etc/GMT+6 -6 - GMT+6 ! Zone Etc/GMT+7 -7 - GMT+7 ! Zone Etc/GMT+8 -8 - GMT+8 ! Zone Etc/GMT+9 -9 - GMT+9 ! Zone Etc/GMT+10 -10 - GMT+10 ! Zone Etc/GMT+11 -11 - GMT+11 ! Zone Etc/GMT+12 -12 - GMT+12 --- 37,65 ---- # zic -l GMT-12 # so we moved the names into the Etc subdirectory. ! Zone Etc/GMT-14 -14 - GMT-14 # 14 hours ahead of GMT ! Zone Etc/GMT-13 -13 - GMT-13 ! Zone Etc/GMT-12 -12 - GMT-12 ! Zone Etc/GMT-11 -11 - GMT-11 ! Zone Etc/GMT-10 -10 - GMT-10 ! Zone Etc/GMT-9 -9 - GMT-9 ! Zone Etc/GMT-8 -8 - GMT-8 ! Zone Etc/GMT-7 -7 - GMT-7 ! Zone Etc/GMT-6 -6 - GMT-6 ! Zone Etc/GMT-5 -5 - GMT-5 ! Zone Etc/GMT-4 -4 - GMT-4 ! Zone Etc/GMT-3 -3 - GMT-3 ! Zone Etc/GMT-2 -2 - GMT-2 ! Zone Etc/GMT-1 -1 - GMT-1 ! Zone Etc/GMT+1 1 - GMT+1 ! Zone Etc/GMT+2 2 - GMT+2 ! Zone Etc/GMT+3 3 - GMT+3 ! Zone Etc/GMT+4 4 - GMT+4 ! Zone Etc/GMT+5 5 - GMT+5 ! Zone Etc/GMT+6 6 - GMT+6 ! Zone Etc/GMT+7 7 - GMT+7 ! Zone Etc/GMT+8 8 - GMT+8 ! Zone Etc/GMT+9 9 - GMT+9 ! Zone Etc/GMT+10 10 - GMT+10 ! Zone Etc/GMT+11 11 - GMT+11 ! Zone Etc/GMT+12 12 - GMT+12

1 0