Hi, I would expect to find the time zone of Iceland/Reykjavik in Europe or Atlantic Ocean but it is in Africa: ------------------------ # tzselect Please identify a location so that time zone rules can be set correctly. Please select a continent, ocean, "coord", or "TZ". 1) Africa 2) Americas 3) Antarctica 4) Asia 5) Atlantic Ocean 6) Australia 7) Europe 8) Indian Ocean 9) Pacific Ocean 10) coord - I want to use geographical coordinates. 11) TZ - I want to specify the timezone using the Posix TZ format. #? 1 Please select a country whose clocks agree with yours. 1) Algeria 20) Gabon 39) Nigeria 2) Angola 21) Gambia 40) Rwanda 3) Benin 22) Ghana 41) Sao Tome & Principe 4) Botswana 23) Guinea 42) Senegal 5) Burkina Faso 24) Guinea-Bissau 43) Sierra Leone 6) Burundi 25) Iceland 44) Somalia 7) Cameroon 26) Kenya 45) South Africa 8) Central African Rep. 27) Lesotho 46) South Sudan 9) Chad 28) Liberia 47) Spain 10) Comoros 29) Libya 48) St Helena 11) Congo (Dem. Rep.) 30) Madagascar 49) Sudan 12) Congo (Rep.) 31) Malawi 50) Tanzania 13) Côte d'Ivoire 32) Mali 51) Togo 14) Djibouti 33) Mauritania 52) Tunisia 15) Egypt 34) Mayotte 53) Uganda 16) Equatorial Guinea 35) Morocco 54) Western Sahara 17) Eritrea 36) Mozambique 55) Zambia 18) Eswatini (Swaziland) 37) Namibia 56) Zimbabwe 19) Ethiopia 38) Niger #? 25 The following information has been given: Iceland Therefore TZ='Africa/Abidjan' will be used. Selected time is now: Fri Sep 15 05:44:06 GMT 2023. Universal Time is now: Fri Sep 15 05:44:06 UTC 2023. Is the above information OK? 1) Yes 2) No #? 1 You can make this change permanent for yourself by appending the line TZ='Africa/Abidjan'; export TZ to the file '.profile' in your home directory; then log out and log in again. Here is that TZ value again, this time on standard output so that you can use the /usr/bin/tzselect command in shell scripts: Africa/Abidjan ------------------------ Why is it mapped to 'Africa/Abidjan'? # tzselect --version tzselect (GNU libc) 2.35 release of tz code and data: 2023c Thx, Reinhard
Reinhard wrote:
I would expect to find the time zone of Iceland/Reykjavik in Europe or Atlantic Ocean but it is in Africa: [...] Why is it mapped to 'Africa/Abidjan'?
Since 1970, Iceland has used the same time zone — namely, GMT+0 with no DST — as Côte d’Ivoire (whose capital is Abidjan) and several other African countries. The tz database does not list separate zones for each sovereign nation that has shared the same time zone history since 1970. The population of Abidjan is more than 16 times that of the entire nation of Iceland, let alone Reykjavík, which is probably why Abidjan was selected to represent that time zone. -- Doug Ewell, CC, ALB | Lakewood, CO, US | ewellic.org
Thanks. I understand that the tz database cannot list a separate zone for each nation but Iceland is close to the Arctic Cycle whereas the nortern part of Africa is close to the equator. The shortest distance between Iceland and Africa is 3200 km! Nobody who knows Iceland would search it in Africa. We got complaints from customers that they couldn't find the time zone of Iceland. Reinhard Am 09.11.23 um 23:40 schrieb Doug Ewell:
Reinhard wrote:
I would expect to find the time zone of Iceland/Reykjavik in Europe or Atlantic Ocean but it is in Africa: [...] Why is it mapped to 'Africa/Abidjan'?
Since 1970, Iceland has used the same time zone — namely, GMT+0 with no DST — as Côte d’Ivoire (whose capital is Abidjan) and several other African countries.
The tz database does not list separate zones for each sovereign nation that has shared the same time zone history since 1970.
The population of Abidjan is more than 16 times that of the entire nation of Iceland, let alone Reykjavík, which is probably why Abidjan was selected to represent that time zone.
-- Doug Ewell, CC, ALB | Lakewood, CO, US | ewellic.org
Reinhard via tz wrote in <78050035-e1c7-d863-ce65-82108b3b4f34@schwilli.at>: |Thanks. |I understand that the tz database cannot list a separate zone for each |nation but Iceland is close to the Arctic Cycle whereas the nortern part |of Africa is close to the equator. The shortest distance between Iceland |and Africa is 3200 km! Nobody who knows Iceland would search it in Africa. |We got complaints from customers that they couldn't find the time zone |of Iceland. They shall go over the street and talk to the government member of Iceland who is on this list. (And maybe take a bath in the famous hot paddle pond.) Ie these are vikings, not chickens. --steffen | |Der Kragenbaer, The moon bear, |der holt sich munter he cheerfully and one by one |einen nach dem anderen runter wa.ks himself off |(By Robert Gernhardt)
Steffen Nurpmeso wrote in <20231109232349.5RxoZ%steffen@sdaoden.eu>: |Reinhard via tz wrote in | <78050035-e1c7-d863-ce65-82108b3b4f34@schwilli.at>: ||Thanks. ||I understand that the tz database cannot list a separate zone for each ||nation but Iceland is close to the Arctic Cycle whereas the nortern part ||of Africa is close to the equator. The shortest distance between Iceland ||and Africa is 3200 km! Nobody who knows Iceland would search it in Africa. ||We got complaints from customers that they couldn't find the time zone ||of Iceland. | |They shall go over the street and talk to the government member of |Iceland who is on this list. (And maybe take a bath in the famous |hot paddle pond.) Ie these are vikings, not chickens. What i meant was: edit $(command -v tzselect) and change zonetabtype=zone1970 to zonetabtype=zone and Iceland will appear in the Antarctic Ocean where it belongs. --steffen | |Der Kragenbaer, The moon bear, |der holt sich munter he cheerfully and one by one |einen nach dem anderen runter wa.ks himself off |(By Robert Gernhardt)
On 11/9/23 15:55:28, Reinhard via tz wrote:
Thanks. I understand that the tz database cannot list a separate zone for each nation but Iceland is close to the Arctic Cycle whereas the nortern part of Africa is close to the equator. The shortest distance between Iceland and Africa is 3200 km! Nobody who knows Iceland would search it in Africa. We got complaints from customers that they couldn't find the time zone of Iceland.
o What is the background of your customers? o What problem(s) are they trying to solve? o What tools/techniques are they using? o What would have been a better way? I had been unfamiliar with tzselect. Is there a FAQ I should have read? (That's a meta-FAQ.) tzselect seems Linux-centric. (It's not available on MacOS.) It may not meet your customers' needs. Are there similar facilities on other OSes? -- gil
On Nov 9, 2023, at 2:40 PM, Doug Ewell via tz <tz@iana.org> wrote:
Reinhard wrote:
I would expect to find the time zone of Iceland/Reykjavik in Europe or Atlantic Ocean but it is in Africa: [...] Why is it mapped to 'Africa/Abidjan'?
Since 1970, Iceland has used the same time zone — namely, GMT+0 with no DST — as Côte d’Ivoire (whose capital is Abidjan) and several other African countries.
But that should not result in tzselect showing Iceland as being in Africa rather than in the Atlantic Ocean; that's a bad user experience. At the end of zone1970.tab there are some lines: # # The next section contains experimental tab-separated comments for # use by user agents like tzselect that identify continents and oceans. # # For example, the comment "#@AQ<tab>Antarctica/" means the country code # AQ is in the continent Antarctica regardless of the Zone name, # so Pacific/Auckland should be listed under Antarctica as well as # under the Pacific because its line's country codes include AQ. # # If more than one country code is affected each is listed separated # by commas, e.g., #@IS,SH<tab>Atlantic/". If a country code is in # more than one continent or ocean, each is listed separated by # commas, e.g., the second column of "#@CY,TR<tab>Asia/,Europe/". # # These experimental comments are present only for country codes where # the continent or ocean is not already obvious from the Zone name. # For example, there is no such comment for RU since it already # corresponds to Zone names starting with both "Europe/" and "Asia/". # #@AQ Antarctica/ #@IS,SH Atlantic/ #@CY,TR Asia/,Europe/ #@SJ Arctic/ #@CC,CX,KM,MG,YT Indian/ Perhaps the experiment needs to wrap up and that stuff needs to be enabled, if it'll fix this.
On 11/9/23 15:05, Guy Harris via tz wrote:
Perhaps the experiment needs to wrap up and that stuff needs to be enabled, if it'll fix this.
That stuff is already enabled; see the example transcript below, which locates Iceland in the Atlantic Ocean. My guess is that the users were running an old version of tzcode, and merely need to upgrade. $ tzselect Please identify a location so that time zone rules can be set correctly. Please select a continent, ocean, "coord", "TZ", or "time". 1) Africa 2) Americas 3) Antarctica 4) Arctic Ocean 5) Asia 6) Atlantic Ocean 7) Australia 8) Europe 9) Indian Ocean 10) Pacific Ocean 11) coord - I want to use geographical coordinates. 12) TZ - I want to specify the timezone using the Posix TZ format. 13) time - I know local time already. #? 6 Please select a country whose clocks agree with yours. 1) Bermuda 2) Cape Verde 3) Falkland Islands 4) Faroe Islands 5) Iceland 6) Portugal 7) South Georgia & the South Sandwich Islands 8) Spain 9) St Helena #? 5 Based on the following information: Iceland TZ='Africa/Abidjan' will be used. Selected time is now: Fri Nov 10 03:08:06 GMT 2023. Universal Time is now: Fri Nov 10 03:08:06 UTC 2023. Is the above information OK? 1) Yes 2) No #? 1 You can make this change permanent for yourself by appending the line TZ='Africa/Abidjan'; export TZ to the file '.profile' in your home directory; then log out and log in again. Here is that TZ value again, this time on standard output so that you can use the /tmp/tz/usr/bin/tzselect command in shell scripts: Africa/Abidjan
On 11/9/23 20:11:04, Paul Eggert via tz wrote:
On 11/9/23 15:05, Guy Harris via tz wrote:
Perhaps the experiment needs to wrap up and that stuff needs to be enabled, if it'll fix this.
That stuff is already enabled; see the example transcript below, which locates Iceland in the Atlantic Ocean.
My guess is that the users were running an old version of tzcode, and merely need to upgrade.
Yes.. I can't reproduce the behavior reported by the OP. Would the following help as diagnostics?: 578 $ tzselect --version tzselect (GNU libc) 2.35 579 $ 579 $ grep From /usr/share/zoneinfo/zone* /usr/share/zoneinfo/zone1970.tab:# From Paul Eggert (2018-06-27): /usr/share/zoneinfo/zone.tab:# From Paul Eggert (2018-06-27): -- gil
On 2023-11-09 20:11, Paul Eggert via tz wrote:
On 11/9/23 15:05, Guy Harris via tz wrote:
Perhaps the experiment needs to wrap up and that stuff needs to be enabled, if it'll fix this.
That stuff is already enabled; see the example transcript below, which locates Iceland in the Atlantic Ocean.
My guess is that the users were running an old version of tzcode, and merely need to upgrade.
$ tzselect Please identify a location so that time zone rules can be set correctly. Please select a continent, ocean, "coord", "TZ", or "time". 1) Africa 2) Americas 3) Antarctica 4) Arctic Ocean 5) Asia 6) Atlantic Ocean 7) Australia 8) Europe 9) Indian Ocean 10) Pacific Ocean 11) coord - I want to use geographical coordinates. 12) TZ - I want to specify the timezone using the Posix TZ format. 13) time - I know local time already. #? 6 Please select a country whose clocks agree with yours. 1) Bermuda 2) Cape Verde 3) Falkland Islands 4) Faroe Islands 5) Iceland 6) Portugal 7) South Georgia & the South Sandwich Islands 8) Spain 9) St Helena #? 5
Based on the following information:
Iceland
TZ='Africa/Abidjan' will be used. Selected time is now: Fri Nov 10 03:08:06 GMT 2023. Universal Time is now: Fri Nov 10 03:08:06 UTC 2023. Is the above information OK? 1) Yes 2) No #? 1
You can make this change permanent for yourself by appending the line TZ='Africa/Abidjan'; export TZ to the file '.profile' in your home directory; then log out and log in again.
Here is that TZ value again, this time on standard output so that you can use the /tmp/tz/usr/bin/tzselect command in shell scripts: Africa/Abidjan
While this may be technically correct, this is jarring to anyone seeing it, and poor UX: linking zones not in geographical proximity across continents or oceans should never happen e.g. {Asia,Europe}/Istanbul makes sense, Atlantic/Reykjavik <-> Africa/Abidjan does not. Nobody would think these might be equivalent nor answer Yes: they would infer this must be an error, and it is, even if not technically! -- Take care. Thanks, Brian Inglis Calgary, Alberta, Canada La perfection est atteinte Perfection is achieved non pas lorsqu'il n'y a plus rien à ajouter not when there is no more to add mais lorsqu'il n'y a plus rien à retirer but when there is no more to cut -- Antoine de Saint-Exupéry
On Nov 9, 2023, at 10:19 PM, Brian Inglis via tz <tz@iana.org> wrote:
While this may be technically correct, this is jarring to anyone seeing it, and poor UX:
The *ideal* UX would never show tzids to any users other than nerds familiar with the tzdb, including the Theory page.
linking zones not in geographical proximity across continents or oceans should never happen e.g. {Asia,Europe}/Istanbul makes sense, Atlantic/Reykjavik <-> Africa/Abidjan does not.
{Asia,Europe}/Istanbul makes sense because the Bosphorus 1) is considered a border between Europe and Asia and 2) runs through Istanbul, so Istanbul is in both continents. Couple of other links that exist but that don't refer to the same city: Europe/Berlin <-> Europe/Copenhagen refer to cities somewhat in geographical proximity (albeit separated by water), although they're ~400 km apart, and I think some complaints were made when Europe/Copenhagen was moved to backbone. America/Panama <-> America/Coral_Harbour are nominally on the same continent, if you consider the Western Hemisphere to have one big continent and some islands, but "proximity" here is "only a little more than 6000 km apart". So either 1) "geographical proximity" needs to be defined more precisely, 2) more criteria are needed for "don't link them", or 3) "don't show tzids to the majority of users".
Guy Harris wrote:
Why is it mapped to 'Africa/Abidjan'?
Since 1970, Iceland has used the same time zone — namely, GMT+0 with no DST — as Côte d’Ivoire (whose capital is Abidjan) and several other African countries.
But that should not result in tzselect showing Iceland as being in Africa rather than in the Atlantic Ocean; that's a bad user experience.
I was focusing on what I thought was the OP’s main concern — that the actual tz identifier that covers Iceland is Africa/Abidjan, and not Atlantic/something or Europe/something — and not on the tzselect tool. -- Doug Ewell, CC, ALB | Lakewood, CO, US | ewellic.org
On 2023-11-10 07:59, Doug Ewell via tz wrote:
I was focusing on what I thought was the OP’s main concern
The original poster's main concern was that tzselect's top level gives you the choice of Africa, Americas, Antarctica, Asia, Atlantic, etc. and that it is unexpected that Iceland is listed under Africa. This problem was fixed in tzdb 2022c. It was a fix to both code and data, so you need 2022c-or-later tzselect combined with 2022c-or-later zone1970.tab to get the fixed behavior.
Paul Eggert wrote:
I was focusing on what I thought was the OP’s main concern
The original poster's main concern was that tzselect's top level gives you the choice of Africa, Americas, Antarctica, Asia, Atlantic, etc. and that it is unexpected that Iceland is listed under Africa.
OK, I’m glad I misunderstood, because ultimately it should make no difference what the actual underlying tzid is, as long as it correctly represents the time situation for the region. -- Doug Ewell, CC, ALB | Lakewood, CO, US | ewellic.org
Thanks for your comments. The problem was sitting between chair and keyboard. It used a wrong combination of tzdata and tzcode. Reinhard Am 10.11.23 um 17:44 schrieb Doug Ewell via tz:
Paul Eggert wrote:
I was focusing on what I thought was the OP’s main concern
The original poster's main concern was that tzselect's top level gives you the choice of Africa, Americas, Antarctica, Asia, Atlantic, etc. and that it is unexpected that Iceland is listed under Africa.
OK, I’m glad I misunderstood, because ultimately it should make no difference what the actual underlying tzid is, as long as it correctly represents the time situation for the region.
-- Doug Ewell, CC, ALB | Lakewood, CO, US | ewellic.org
participants (8)
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Brian Inglis -
Doug Ewell -
Guy Harris -
Paul Eggert -
Paul Gilmartin -
Reinhard -
Steffen Nurpmeso -
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