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From: Dr J R Stockton on 18 Mar 2010 16:31 In comp.lang.java.programmer message <c5r0q516d182h35q6jsad1nk7hdl5iuv5t @4ax.com>, Tue, 16 Mar 2010 22:49:26, Roedy Green <see_website(a)mindprod. com.invalid> posted: >On Tue, 16 Mar 2010 13:24:12 +0000, Dr J R Stockton ><reply1011(a)merlyn.demon.co.uk> wrote, quoted or indirectly quoted >someone who said : > >>Codswallop and balderdash. The proper date for that is the last Sunday >>in March and the proper time is 01:00 UTC (or GMT), which all Canadians >>should realise. The proper date to change back is the last Sunday in >>October, at the same UTC. > >Not any more. Remember Mr. Bush extended the range of DST. Mr Bush is, and was, irrelevant (and North America previously used the first Sunday in April). Moreover, while the Energy Policy Act of 2005 applied throughout America, that part of the Act did not have effect throughout America. The States are not in all respects United. Neither is Canada; the Provinces decided independently to use the new days, but do not all change at the same local time - NRC has a Time FAQ. >The 2:00 AM local time rule is what I learned as a young child, and in >general that is when public clocks change in my part of the world. But you said nothing about your part of the world in your initial post. You wrote "Your computer should have automatically set your PC clock ahead 1 hour at 2AM this morning.". You were addressing a world-wide, if sparse, readership. The whole world does not revolve around your country's southern appendage. It generally agrees with what Churchill might have said about them. That sentence is full of error. There, "computer" should be plural; I have four - the one which runs DOS cannot alter its time; the correct time to change in Spring is 01:00 previous local (01:00 UTC or GMT); the correct date is the last Sunday in March ... and it's unreasonable to expect them to do anything at that sort of time, since they are all turned completely off, externally to themselves[*]. >What is your source for 1:00 UTC? For such things, consult <URL:http://www.merlyn.demon.co.uk/uksumtim.htm>. The efficient source is The Summer Time Order 2002, of which there is a copy at <http://www.opsi.gov.uk/si/si2002/20020262.htm>. That is an Order of your Monarch, albeit not one aimed at you, implementing for the UK an EU Directive. One hopes that the Lord of Mann issued a similar order. [*] On general grounds, virtually every night; with special care to do so around local 00:59-02:01 on the last Sunday in March, and around local 00:59-02:01 on the last Sunday in October. -- (c) John Stockton, nr London, UK. ?@merlyn.demon.co.uk Turnpike v6.05. Web <URL:http://www.merlyn.demon.co.uk/> - w. FAQish topics, links, acronyms PAS EXE etc : <URL:http://www.merlyn.demon.co.uk/programs/> - see 00index.htm Dates - miscdate.htm estrdate.htm js-dates.htm pas-time.htm critdate.htm etc.
From: bugbear on 19 Mar 2010 08:22 Roedy Green wrote: > On Mon, 15 Mar 2010 09:54:17 +0000, bugbear > <bugbear(a)trim_papermule.co.uk_trim> wrote, quoted or indirectly quoted > someone who said : > >>> Your computer should have automatically set your PC clock ahead 1 hour >>> at 2AM this morning. >> No it shouldn't! > > I presume by that you mean the UTC time should not have shifted, just > the displayed local time? Or that this only applies to Canada and the > USA? The latter... BugBear
From: Roedy Green on 20 Mar 2010 09:24 On Thu, 18 Mar 2010 20:31:57 +0000, Dr J R Stockton <reply1011(a)merlyn.demon.co.uk> wrote, quoted or indirectly quoted someone who said : > >>The 2:00 AM local time rule is what I learned as a young child, and in >>general that is when public clocks change in my part of the world. National TV gave me the impression DST was informally implemented across Canada, with the exception of Saskatchewan who stick to "God's time". I was astounded to find out it is far from so. In most of Canada, DST begins and ends at 2 AM on the same days as the USA. However, in Newfoundland and Labrador, DST begins one minute after midnight local time on the second Sunday in March. On the first Sunday in November time returns to standard at one minute after midnight local time. A few areas of Canada don�t use DST at all including Fort St. John, Charlie Lake, Taylor and Dawson Creek, Creston in British Columbia, and most of Saskatchewan (except Denare Beach and Creighton). It seems so odd I could have visited Creston several times without noticing this. -- Roedy Green Canadian Mind Products http://mindprod.com Responsible Development is the style of development I aspire to now. It can be summarized by answering the question, �How would I develop if it were my money?� I�m amazed how many theoretical arguments evaporate when faced with this question. ~ Kent Beck (born: 1961 age: 49) , evangelist for extreme programming.
From: Roedy Green on 20 Mar 2010 09:35 On Thu, 18 Mar 2010 20:31:57 +0000, Dr J R Stockton <reply1011(a)merlyn.demon.co.uk> wrote, quoted or indirectly quoted someone who said : >and it's unreasonable to >expect them to do anything at that sort of time, since they are all >turned completely off, externally to themselves[*]. PCs running recent versions of Windows adjust themselves just fine when you turn them back on. For the recent Windows, nothing happens to the CMOS clock, just to the software that displays the current value. If they are powered on, you can see them change (in my case) bang on at 2 AM). For XT-era, what happened depended on your proprietary clock driver. For AT-era, you had to manually set the clock forward and back an hour since the CMOS clock kept local time. An the OS was not prepared to do the sort of timezone bookkeeping that Java and Windows 7 do. What we do now was not really feasible without weekly Internet automatic updates to keep time zone tables up to date. DST is an idiotic idea that just complicates timekeeping and guarantees errors. I wonder how many people have died as a result of errors caused by DST. I wonder the aggregate cost of all the missed appointments. -- Roedy Green Canadian Mind Products http://mindprod.com Responsible Development is the style of development I aspire to now. It can be summarized by answering the question, �How would I develop if it were my money?� I�m amazed how many theoretical arguments evaporate when faced with this question. ~ Kent Beck (born: 1961 age: 49) , evangelist for extreme programming.
From: Dr J R Stockton on 20 Mar 2010 14:09
In comp.lang.java.programmer message <39GdnSt5Lps88T7WnZ2dnUVZ7odi4p2d@b rightview.co.uk>, Fri, 19 Mar 2010 12:22:57, bugbear <bugbear(a)trim_paper mule.co.uk_trim> posted: >Roedy Green wrote: >> On Mon, 15 Mar 2010 09:54:17 +0000, bugbear >> <bugbear(a)trim_papermule.co.uk_trim> wrote, quoted or indirectly quoted >> someone who said : >> >>>> Your computer should have automatically set your PC clock ahead 1 >>>>hour >>>> at 2AM this morning. >>> No it shouldn't! >> I presume by that you mean the UTC time should not have shifted, >>just >> the displayed local time? Or that this only applies to Canada and the >> USA? > >The latter... Parts of the USA and parts of Canada do not use DST. Part of Canada changes at different times. Other parts of North America, apparently including Cuba, use the same date for at least one of the annual changes. Uruguay & Paraguay also change on 2 Sun Mar, but not as described. -- (c) John Stockton, nr London, UK. ?@merlyn.demon.co.uk Turnpike v6.05. Web <URL:http://www.merlyn.demon.co.uk/> - w. FAQish topics, links, acronyms PAS EXE etc : <URL:http://www.merlyn.demon.co.uk/programs/> - see 00index.htm Dates - miscdate.htm estrdate.htm js-dates.htm pas-time.htm critdate.htm etc. |