kka059@MIPL3.JPL.NASA.GOV (11/05/87)
Here's a second attempt to post this message... In message <1362@bsu-cs.UUCP>, Rahul Dhesi writes: >In article <4709@elroy.Jpl.Nasa.Gov> david@elroy.Jpl.Nasa.Gov (David Robinson) >writes: >>Simply have DEC maintain in kernel >>all times in a fixed timezone (GMT?) ... > >It's bad enough that the quaint ancient practice of referring to Her >Majesty's Royal Greenwich Observatory's local time as a standard hasn't >died yet. Worse, you folks now want modern, state-of-the-art operating >systems such as VMS to be defiled in this manner. Does this mean that no one objects to having all VAX system times defined in terms of a standard that no one (unless they dwell deep inside of DEC) recognizes? The standard to which I refer is: ...the system base date and time, which is 00:00 o'clock [sic] November 17, 1858 (the Smithsonian base data and time for the astronomical calendar)... VAX/VMS System Services Reference Manual page 9-2, Section 9.1 The System Time Format Unfortunately, no one at either the Smithsonian Museum in Washington, D.C. or at the Smithsonian Astrophysical Observatory in Massachusetts had *ever* heard of this ``astronomical calendar;'' not to mention that they were supposed to have been responsible for it! If anyone at DEC can shed some rays of enlightenment upon this mysterious standard, it would be delightful. (I also have a gentlemanly wager upon it.) Also, in message <8711020746.AA21981@ucbvax.Berkeley.EDU>, Jerry Leichter refers to ``UCT'' as some time standard. I wonder whether he meant ``UTC,'' having neglected to note that it is part of the SI, i.e. metric system, of weights and measures. The French have a delightful syntax wherein the adjectives follow the modified nouns (remember *all* rules have exceptions). Therefore, Universal Coordinated Time is UTC, universalle time coordinate (please excuse any misspellings of the French). Come to think of it though, aren't we all being just a bit quaint to use a time system based upon the hypothesized date of birth, now believed by scholars to be off by some seven years, of an historical figure and developed by a significant (according to some people) force of colonial repression, the Roman catholic church? +----------------------------+------------------------------------------+ | Kurt Andersen | Jet Propulsion Laboratory | | MIPL Applications | Mail Stop 168-427 | | Programmer | 4800 Oak Grove Drive | | Office: 169-425 | Pasadena, Calif. 91109 | +----------------------------+-------------------------+----------------+ | NETWORKS: | Does the verb | | SPAN: Mipl3::KKA059 (5.153) | "to flame" | | ARPA Internet: KKA059@Mipl3.Jpl.Nasa.Gov | come from the | | Internet Address: [128.149.1.28] | days of the | | ARPAnet->SPAN: KKA059%Mipl3@Star.Stanford.Edu | | | or: KKA059%Mipl3.Span@Jpl-Vlsi.Arpa | Inquisition? | | Ma Bell (R.I.P.): (818) 354-1672 | | +------------------------------------------------------+----------------+
IMHW400@INDYVAX.BITNET (11/10/87)
A historical note: DEC's TOPS-20 operating system (no boos, please) maintains
the system time as GMT based on that same "Smithsonian" standard epoch. One of
the system startup parameters is the offset from GMT to local time. The system
services that perform date conversion will use this offset unless told to use
some other time zone, can handle the usual symbolic time zones as part of a
date-time string, and will apply or not apply DST as requested. So DEC has
done it all at least once before, and should be able to do it again for their
flagship operating system. It all works rather well; the only problem I've
had with all of this is that Congress keeps changing the dates on which DST is
turned on and off, so DEC keeps having to edit the system, maintaining an
ever-growing list of rules for DST. At this site we are moving from TOPS to
VMS, and one of the first surprises I had regarding VMS was the bare-bones
date conversion services.
{FLAME ON!}
One thing that would help a lot is if we could all give up the idea of
twiddling the clocks twice a year. Indiana does not observe DST, and the
most significant consequence of that seems to be that the television schedule
changes in spring and fall. (On the telephone, one does have to remember that
one is in CDT in the summer and EST in the winter.)
{flame off}
I should know better than to start this issue up again, as the volume of flames
on this subject would probably justify the creation of an INFO-DST list. Feel
free to chastise me privately.dhesi@bsu-cs.UUCP (Rahul Dhesi) (11/12/87)
In article <8711102237.AA03147@ucbvax.Berkeley.EDU> IMHW400@INDYVAX.BITNET writes: [Indiana does not fool around with clocks twice a year so] on the telephone, one does have to remember that one is in CDT in the summer and EST in the winter. Not at all; it is enough to remember that one is in EST year round, which is the same as saying that one is in CDT year round. EST = CDT = GMT+5 This thorughly confuses people, which is the way it should be. Daylight savings is stupid. For that matter, four timezones in continental USA are stupid too. They should have only two: one for the eastern half, and one for the western half, differing by two hours. -- Rahul Dhesi UUCP: <backbones>!{iuvax,pur-ee,uunet}!bsu-cs!dhesi
eggert@grand.UUCP (11/12/87)
In article <871105071449.002@Mipl3.JPL.Nasa.Gov> kka059@MIPL3.JPL.NASA.GOV (Kurt Andersen) writes: ...the system base date and time, which is 00:00 o'clock [sic] November 17, 1858 (the Smithsonian base data and time for the astronomical calendar)... VAX/VMS System Services Reference Manual page 9-2, Section 9.1 The System Time Format Unfortunately, no one at ... at the Smithsonian ... had *ever* heard of this ``astronomical calendar;'' not to mention that they were supposed to have been responsible for it! I asked Bob Uzgalis, a friend who is writing a book about calendars but who like me knows nothing of DEC time, about this. He replied: I wouldn't wager, but I wouldn't be surprised if 0h November 17th 1858 was an ephemeris date... and that it was an `astronomical standard' for ten years or so until precession and/or a new edition made another date appropriate. After all the first edition of _Practical Astronomy with Your Calculator_ (Duffett-Smith) used Jan 0.0 1970 as its epoch date/time and the second edition uses Jan 0.0 1980. I vote for 0h BC 4713 Jan 1 (Julian Calendar, of course) as a good system base date. Use one 32-bit word for the day (which will cover 11.8 million years) and another for the time (resolution of 20 microseconds). This of course avoids problems with leap seconds, which fall into the gap between days and seconds. Maybe DEC would be interested in starting the ball rolling? He did not pick BC 4713 Jan 1 out of a hat. It has been used as a common, absolute time origin by astronomers for 400 years or so. DEC seemingly did not realize this and thought that some old Smithsonian ephemeris was permanent. Obviously the new format should be UTC (ie GMT) as well. While we're on the subject, a report in the latest _Science_ claims that some pulsars are more accurate than the most accurate atomic clocks. If this is true, we could switch back to a natural phenomenon for our time standard! A corollary of the accuracy of the measurement is an upper bound on the mass of the universe (otherwise gravitational waves would have spoiled the accuracy). I urge time hounds to read this fascinating report. --paul
hildum@iris.ucdavis.edu (Eric Hildum) (11/12/87)
Hello. Just to give you an idea how seriously people take the wall clock "time;" when the idea of shifting back and forth one hour was first suggested, it was strongly opposed by those who feared that the extra hour of daylight would burn the crops in the fields. Eric
IVANOVIC%VAXR@LLL-ICDC.ARPA ("Vladimir Ivanovic, x3-7786") (11/16/87)
Rahul Dhesi writes:
Daylight savings is stupid. For that matter, four timezones in
continental USA are stupid too. They should have only two: one for
the eastern half, and one for the western half, differing by two hours.
One of the stated reasons for Daylight Savings Time is to increase the
amount of light when schoolchilden board buses in the morning, thereby
reducing the number of accidents. Is that stupid?
Seems to me that Rahul Dhesi ought to rephrase his comments to delete the
name calling and instead provide reasoning for his points of view. We
might just agree.
-- Vladimirali1@ntvax.UUCP (11/21/87)
As will no doubt occur, several people will have responded to the origin of the November time as DEC's zero-hour selection; I'll be brief... Now I don't recall where I read it, but it is my understanding that this particular time represents the exact time, many moons ago, that the first photograph of the astronimcal heavans was produced.
dhesi@bsu-cs.UUCP (Rahul Dhesi) (11/23/87)
In article <8711220353.AA03743@ucbvax.Berkeley.EDU> IVANOVIC%VAXR@LLL-ICDC.ARPA ("Vladimir Ivanovic, x3-7786") writes: >One of the stated reasons for Daylight Savings Time is to increase the >amount of light when schoolchilden board buses in the morning, thereby >reducing the number of accidents. Is that stupid? Yes. First you set a school starting time that's too early in the morning, when there isn't enough light, and then you observe too many accidents, so, instead of adjusting the starting time, you tell everybody to change the clock? It sounds like an awfully complicated way of starting school at 9 instead of 8. Most of Indiana does not observe daylight savings time and gets along just fine, and avoids a lot of confusion (and a lot of misadjusted clocks twice a year). Somebody ought to sit down and calculate how many man-hours of labor goes every year into moving clocks backwards and forwards, and into fixing the problems caused by confusion about when daylight savings actually starts, which is not always known in advance, making it much harder to make software behave correctly. You have already seen people asking questions about how to make VMS handle daylight savings correctly. Some people actually reboot their system twice a year just for this purpose. Worse, not all countries agree on when daylight savings will start, which means international carriers have to hit an elusive target with their printed schedules, to say nothing of international broadcasting. The costs are hidden, but you can be sure there are plenty. >Seems to me that Rahul Dhesi ought to rephrase his comments to delete the >name calling and instead provide reasoning for his points of view. We >might just agree. Name-calling directed at inanimate objects ("damn this stupid computer!") or at ideas ("stupid daylight savings") is perfectly civilized behavior. And in this case at least, the label is well-deserved, since I see no way of increasing the amount of daylight short of making the earth rotate at a variable rate, or bringing the sun closer, both options being beyond the current state of technology. -- Rahul Dhesi UUCP: <backbones>!{iuvax,pur-ee,uunet}!bsu-cs!dhesi
jeh@crash.cts.com (Jamie Hanrahan) (11/25/87)
Speaking of time corrections -- those of you who want your VAXes to keep strictly accurate time should plan to set their clocks ahead by one second at 31-Dec-1987 23:59:59.00 . Of course, if you have a WWV receiver updating your clock, the correction will occur automatically. This "leap second" is being added to CUT to compensate for the slowing of the earth's rotation; it is the 14th such adjustment since 1972. (From _Air & Space/Smithsonian_, a bimonthly magazine published by the National Air and Space Museum of the Smithsonian Institution.)
mithomas@bsu-cs.UUCP (Michael Thomas Niehaus) (12/02/87)
These are some messages that have appeared in this newsgroup: > Yes. First you set a school starting time that's too early in the > morning, when there isn't enough light, and then you observe too many > accidents, so, instead of adjusting the starting time, you tell > everybody to change the clock? It sounds like an awfully complicated > way of starting school at 9 instead of 8. Is that all you people think about is school, comupters, time changes, and economics? Why don't you try to discuss something useful like networking (I'm sure you can argue about that for a while). > Most of Indiana does not observe daylight savings time and gets along > just fine, and avoids a lot of confusion (and a lot of misadjusted > clocks twice a year). Somebody ought to sit down and calculate how > many man-hours of labor goes every year into moving clocks backwards > and forwards, and into fixing the problems caused by confusion about Do you think that the sections of Indiana that don't observe daylight savings time have any choice in the matter? Time zones are determined almost exclusively (in the USA) by the Department of Transportaion. > daylight savings correctly. Some people actually reboot their system > twice a year just for this purpose. Worse, not all countries agree on > when daylight savings will start, which means international carriers > have to hit an elusive target with their printed schedules, to say > nothing of international broadcasting. The costs are hidden, but you > can be sure there are plenty. Back to economics. > Name-calling directed at inanimate objects ("damn this stupid > computer!") or at ideas ("stupid daylight savings") is perfectly > civilized behavior. And in this case at least, the label is Now people are even defending computers. As if they care if they are being insulted. Who was that person that who made the name-calling accusation? The first living computer? Even though I am majoring in computer science, I hope that I never live, breathe , and think computers. I only want to know how to use them. Michael Niehaus UUCP: <Backbones>!{iuvax, pur-ee, uunet}!bsu-cs!mithomas