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Summer Time, Channel Islands, 1916
by Joseph S. Myers Sept. 2, 1999

Sept. 2, 1999

I today found the 1916 summer time orders for the Channel Islands in the Public Record Office (HO 45/10811/312364). This resolves one residual dubious claim of Shanks in the europe file: Alderney, Jersey and Guernsey all enacted summer time for 1916 (and the enactment for the Isle of Man is already noted). This doesn't complete the resolution of timekeeping in the Channel Islands, since 1917-1921 need to be resolved for the Channel Islands, and it isn't clear whether the islands were using GMT or local time then. The changes in Alderney and Guernsey were at the same 2am GMT time as for Great Britain; the order for Jersey is more interesting. Other things in this file include a poster advertising the change in Ireland from Dublin-based time to Greenwich mean time, and one advertising the introduction of summer time in the UK in 1916 (100000 copies printed); and the information that (a) it was originally proposed to implement summer time by Order in Council under the Defence of the Realm Acts, but it was decided that although this would be legal it would make things clearer to do it by Act of Parliament; and (b) a Bill to change Ireland to using the same time as England had passed in the Lords in 1912 but was not proceeded with in the Commons. This file, and another (HO 45/11077/411632 - on international coordination of summer time) include various laws and regulations of other European countries on summer time around that time, though the proper histories of summer time in these countries are no doubt more readily created by someone living there. It seems that there was a conference at the Home Office on 22 November 1921 with representative of France and Belgium to discuss reaching common summer time dates with them. Alderney ======== [This one is in manuscript.] A la Cour de l'Ile d'Auregny Le 17 Mai 1916, par devant John Main Duplain, écuyer, Lieut-juge; présents :- John Pierre Gallichan, Nicolas William Gaudion, et Thomas John Robilliard, écuyers, Jurés. ``Ordonnance Provisoire Portant Modification à l'Heure Légale''. La Cour, ouies les conclusions du Procureur du Roi, a ordonné et ordonne :- Dans la présente année, 1916, l'heure légale en cette île sera avancée d'une heure, depuis deux heures du matin (temps moyen de Greenwich) de Dimanche le 21 Mai, jusqu'à deux heures du matin (temps moyen de Greenwich) de Dimanche le 1^er Octobre. Pendant la période susdite, l'heure mentionnée ou à laquelle allusion est faite dans les Proclamations, les Actes de Parlement, les Ordres en Conseil, les Ordonnances de la Cour, en vigueur dans cette île, dans des contrats, des règlements, des statuts, des avertissements, des affiches, ou dans tout autre document ou toute affaire quelconque, sera censée être l'heure préscrite dnas la présente Ordonnance. Et ne déroge en rien cette Ordonnance à l'usage de l'heure, temps moyen de Greenwich, pour les besoins de l'astronomie ou de la navigation ni à l'interprétation d'aucun document qui mentionne ou qui a référence à l'heure ayant rapport à l'astronomie et à la navigation. Et sera la présente Ordonnance publieé et affichée aux lieux ordinaries afin que personne n'en prétende cause d'ignorance. (Extrait des Registres) Charles R Leboeq Greffier du Roi Jersey ====== HEURE OFFICIELLE. ----- Acte avançant l'heure officielle pendant les mois d'été. ----- Aux Etats de l'Ile de Jersey. ----- L'An 1916, le 13e jour de Mai. ----- CONSIDÉRANT que le Parlement Britannique a, dans l'intérêt national, résolu d'avancer d'une heure la computation horaire dans le Royaume-Unia à partir de Dimanche le 21 Mai courant jusqu'à Dimanche le 1er Octobre prochain et ainsi de suite pareillement chaque année durant la présente guerre pendant telle période qui sera prescrite par Ordre de Sa Majesté en Conseil; Considérant que, lors de l'adoption, en 1898, de la Loi qui détermine actuellement l'heure officielle en cette Ile, les Etats ont déjà reconnu et affirmé le princpe que Jersey ne peut sans inconvénients rester en dehors de l'horaire qui prévaut dans las Grande Bretagne; Considérant que la différence entre l'heure locale alors en usage et celle de Greenwich n'était cependant que de quelques minutes tandis que maintenant l'écart de temps entre Jersey et la Grande Bretagne serait d'une heure entière pendant tout l'été, en sorte qu'un changement analogue s'impose ici; LES ETATS ont, d'urgence, adopté la disposition suivante: ARTICLE UNIQUE. Samedi le 20 courant à minuit l'heure officielle en cette Ile sera avancée d'une heure sur le temps moyen de Greenwich et ce jusqu'à Samedi le 30 Septembre prochain à minuit. Pareille avance sera opérée chaque année subséquente tant qu'il y aura nécessité de ce faire, et ce aux époques qui seront en temps et lieu déterminées par les Etats afin que l'heure officielle locale demeure en tout temps conforme à l'heure légale de la Grande Bretagne. Ce qui sera imprimé, publié et affiché. ERNEST LE SUEUR, Greffier. 50/1916 Guernsey ======== ORDONNANCE DE LA COUR ROYALE. ----------- ORDONNANCE PROVISOIRE Portant modification à L'HEURE LÉGALE (Passée aux Chefs-Plaids d'après Pâques remis au 13 mai 1916.) Guernesey: COMPAGNIE D'IMPRIMERIE DE BICHARD, LIMITÉE, BUREAU DE LA GAZETTE, RUE DU BORDAGE. ------ 1916. Ordonnance de la Cour Royale. A LA COUR ROYALE DE L'ILE DE GUERNESEY Aux Chefs-Plaids d'après Pâques remis au 13 mai 1916, pardevant Edward Chepmell Ozanne, écuyer, Bailiff; présents: Ernest Collas, George Edward Kinnersly, George Herbert Le Mottée, Julius Bishop, John Bonamy Collings, Adolphus John Hocart, Thomas William Mansell de Guérin, Lionel Slade Carey, James Esten de Jersey, Hubert George de Carteret Stevens Guille et William de Prélaz Crousaz, écuyers, Jurés. Ordonnance Provisoire portant Modification à l'Heure Légale. La Cour, ouïes les conclusions des Officiers du Roi, a ordonné et ordonne :- Dans la présente année, 1916, l'heure légale en cette île sera avancée d'une heure, depuis deux heures du matin (temps moyen de Greenwich) de Dimanche, le 21 mai, jusqu'à deux heures du matin (temps moyen de Greenwich) de Dimanche, le 1er octobre. Pendant la période susdite, l'heure mentionnée ou à laquelle allusion est faite dans les Proclamations, les Actes de Parlement, les Ordres en Conseil, les Ordonnances de la Cour Royale en vigueur dans cette île, dans des contrats, des règlements, des statuts, des avertissements, des affiches, ou dans tout autre document ou toute affaire quelconque, sera censée être l'heure préscrite dnas la présente Ordonnance. Et ne déroge en rien cette Ordonnance à l'usage de l'heure temps moyen de Greenwich pour les besoins de l'astronomie ou de la navigation ni à l'interprétation d'aucun document qui mentionne ou qui a référence à l'heure ayant rapport à l'astronomie et à la navigation. Et sera la présente Ordonnance publieé et affichée aux lieux ordinaries afin que personne n'en prétende cause d'ignorance. (Extrait des Registres), A. J. ROUSSEL, Député-Greffier du Roi. -- Joseph S. Myers jsm28(a)cam.ac.uk

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C9X and Time
by Clive D.W. Feather Sept. 2, 1999

Sept. 2, 1999

Sorry it's taken me so long to get round to this. The last WG14 meeting agreed, in principle, that a work item could be started on new time facilities for C. The result of the work item would be a Normative Amendment that would add these facilities to the language. There was no objection to the proposal that the facilities be designed "from the ground up"; they do not have to be based on the existing <time.h> functions. Where do we want to go from here ? -- Clive D.W. Feather | Work: <clive(a)demon.net> | Tel: +44 20 8371 1138 Internet Expert | Home: <clive(a)davros.org> | Fax: +44 20 8371 1037 Demon Internet Ltd. | WWW: http://www.davros.org | Mobile: +44 973 377646

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tzdata format
by D. J. Bernstein Aug. 31, 1999

Aug. 31, 1999

Supposedly rule lines can occur in any order. What do the following lines mean? Rule Silly 1999 only - Sep 3 5:00 2:00 X Rule Silly 1999 only - Sep 3 6:00 1:00 Y Rule Silly 1999 only - Sep 3 8:00 -3:00 Z Starting from 0:00 +0000, do we increase to 5:00 +0000, then jump to 7:00 +0200, then increase to 8:00 +0200, then jump to 3:00 -0300, then increase to 6:00 -0300, then jump to 10:00 +0100, then increase? Or do we increase to 6:00 +0000, then jump to 7:00 +0100, then increase to 8:00 +0100, then jump to 4:00 -0300, then increase to 5:00 -0300, then jump to 10:00 +0200, then increase? Why aren't transition times labelled with the starting offset? Or, more simply, always specified in terms of standard time? I see that Tunisia one year had two transitions in the same month. Why are these part of the rule rather than the zone? Are there other examples of two transitions in the same month? Are there any DST systems that don't consist of two jumps in each applicable year, one jump early in the year, one jump late in the year? Are there any rule lines that cover multiple years without being part of such a pair? ---Dan

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Re: time.h design issues
by Ulrich Drepper Aug. 31, 1999

Aug. 31, 1999

Paul Eggert <eggert(a)twinsun.com> writes: > I agree that my proposed API is still too complicated. When I get the > time I'll try to simplify it. Your code is a valuable resource in > this area: implementation experience counts for a lot in my book. Well, then I hope you suggest an implementation for a monotonic time implementation. Constraints are: The underlying OS will not notify each running program about a sudden clock change and itself does not provide a monotonic clock. In this situation the only thing you can count on are some hardware "clocks" the kernel does not (or cannot) influence. I think about things like the time stamp counters found on many modern processors. But: - they are only found on modern processors, and therefore a generic implementation isn't possible - even if they are available, they might be useless if, as in the case of the Alpha, the counter range is too small (just do the math: a 32 bit counter increment in each clock cycle on machines with, as seen two weeks ago, 1GHz clock speed). What I meant to say is think about the implementation before you propose something. It is certainly nice to have such a timer but it is very often not possible to implement it and for exactly this reason we have adjtime(). -- ---------------. drepper at gnu.org ,-. 1325 Chesapeake Terrace Ulrich Drepper \ ,-------------------' \ Sunnyvale, CA 94089 USA Cygnus Solutions `--' drepper at cygnus.com `------------------------

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Tonga Daylight Savings Time
by Eric Ulevik Aug. 31, 1999

Aug. 31, 1999

On 19 August 1999, New Zealand TV's "ONE Network News" reported that Tonga will have DST from November to February, making it first into the new millenium. I don't have any details, unfortunately. Regards, Eric Ulevik eau(a)ozemail.com.au

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FW: timezone improvements
by Olson, Arthur David (NCI) Aug. 30, 1999

Aug. 30, 1999

Robert E. Brown is not on the time zone mailing list; be sure to include Robert in any replies. --ado -----Original Message----- From: Robert E. Brown [SMTP:brownb@jany.gs.com] Sent: Thursday, August 26, 1999 1:24 PM To: tz(a)elsie.nci.nih.gov Subject: timezone improvements I work for a company that requires some capabilities beyond the standard time zone library. Here's the sort of thing we're interested in: Ability to efficiently do time calculations in several time zones at the same time in separate threads. Time zone functions might take a zone as argument instead of the current method of setting the TZ environment variable and calling tzset to change zones, which involves file I/O. Is there any prior art along these lines? I do see the routines whose names end with "_r". They seem to fix one glitch, but do not completely solve the problem. How can I get the capabilities I want integrated with the standard time zone library? By making it a part of the standard library, the chance increases that the code will be used, maintained, and completely debugged. We are willing to pay for the capabilities we want. Would Cygnus be a good source for this work? Do you have any other suggestions? Thanks very much. bob

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Re: FW: timezone improvements
by Ulrich Drepper Aug. 27, 1999

Aug. 27, 1999

> How can I get the capabilities I want integrated with the standard time zone > library? By making it a part of the standard library, the chance increases > that the code will be used, maintained, and completely debugged. We are > willing to pay for the capabilities we want. Would Cygnus be a good source > for this work? Do you have any other suggestions? Thanks very much. I don't know exactly why you are referring to Cygnus. I guess because you associate my glibc work with my employer. And I also don't know which "standard library" you are referring to. glibc as used on Linux? You will most probably be out of luck trying to influence the commercial Unix vendors. If you know what interface you are looking for contact me and I can see whether it makes sense adding it to glibc. -- ---------------. drepper at gnu.org ,-. 1325 Chesapeake Terrace Ulrich Drepper \ ,-------------------' \ Sunnyvale, CA 94089 USA Cygnus Solutions `--' drepper at cygnus.com `------------------------

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timezone improvements
by Robert E. Brown Aug. 26, 1999

Aug. 26, 1999

I work for a company that requires some capabilities beyond the standard time zone library. Here's the sort of thing we're interested in: Ability to efficiently do time calculations in several time zones at the same time in separate threads. Time zone functions might take a zone as argument instead of the current method of setting the TZ environment variable and calling tzset to change zones, which involves file I/O. Is there any prior art along these lines? I do see the routines whose names end with "_r". They seem to fix one glitch, but do not completely solve the problem. How can I get the capabilities I want integrated with the standard time zone library? By making it a part of the standard library, the chance increases that the code will be used, maintained, and completely debugged. We are willing to pay for the capabilities we want. Would Cygnus be a good source for this work? Do you have any other suggestions? Thanks very much. bob

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Historical zone changes
by Lblumbbs＠aol.com Aug. 19, 1999

Aug. 19, 1999

In December 1941 I understand the time in Hawaii when it is on the hour in the Eastern Standard time zone was 30 minutes past the hour. Today ther minutes are the same. Can you tell me what the time zone difference between the Eastern Standard time zone and the time zone covering Hawaii was in 1941? Can you tell when (year and month) any changes to this time difference changed.

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Re: tzcode1999e.tar.gz and tzdata1999e.tar.gz
by Ulrich Drepper Aug. 17, 1999

Aug. 17, 1999

Ado, > The files > ftp://elsie.nci.nih.gov/pub/tzcode1999e.tar.gz > and > ftp://elsie.nci.nih.gov/pub/tzdata1999e.tar.gz Unfortunately the files are not readable in the moment: -r-------- 1 8800 0 92586 Aug 17 19:28 tzcode1999e.tar.gz -r-------- 1 8800 0 104493 Aug 17 19:28 tzdata1999e.tar.gz -- ---------------. drepper at gnu.org ,-. 1325 Chesapeake Terrace Ulrich Drepper \ ,-------------------' \ Sunnyvale, CA 94089 USA Cygnus Solutions `--' drepper at cygnus.com `------------------------

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