Newsgroups: alt.folklore.computers Subject: Epochs in VMS (was Re: Never mind the millenium bug....) Date: 23 Jan 1998 19:50:56 GMT Organization: Department of Mathematics, The Ohio State University Lines: 55 Message-ID: <6aasb0$5vk$1@mathserv.mps.ohio-state.edu> References: <34c63ca2.0@news.power.net.uk> <6a5e4t$grl$1@nntp.ucs.ubc.ca> <885548084snz@tnglwood.demon.co.uk> NNTP-Posting-Host: math.mps.ohio-state.edu X-Newsreader: trn 4.0-test60 (5 October 1997) Originator: dicks@math.ohio-state.edu (Ethan Dicks) Path: ccw.ch!aetna.dolphins.ch!news.planetc.com!atl-news-feed1.bbnplanet.com!cpk-news-hub1.bbnplanet.com!news.bbnplanet.com!news.maxwell.syr.edu!news.cis.ohio-state.edu!math.ohio-state.edu!not-for-mail In article <885548084snz@tnglwood.demon.co.uk>, Robert Billing wrote: >In article <6a5e4t$grl$1@nntp.ucs.ubc.ca> > shoppa@alph02.triumf.ca "Tim Shoppa" writes: > >> bit will become set. All of the signed compares will then become backwards, >> causing much havoc. The havoc ranges from just generally loopy operation > > Which is why I have been coding them as unsigned for 15ish years, and >as time_t once the standard was established. The VMS clock OTOH has >about 60,000 years to go. It is coded as 64 bit units of 100ns since >the Smithsonian base date (around 1857 IIRC). November 17th, 1958 (cf Barkes, Kevin G., "Fast Eddit And The Time Machine", "DEC PROFESSIONAL", November, 1991, vol 10, no. 12, pp106-110 And it's 100ns intervals until approx 3 A.M., July 31st., 31086 (64 bits, but a signed quadword - "negative time" in VMS is used for delta intervals). > Someone once told me that the Smithsonian base date was the date of >the first photographic plate used for astronomy. Can anyone confirm or >deny this? According to the same article, the Smithsonian Astrophysical Observatory (SAO) adopted the usage of the "Modified Julian Day" in 1957 for tracking satellites in order to avoid squandering memory on their IBM computer. The Julian Day 2,400,000 is November 17th, 1858, making January 1st, 1957 to 2,435,839. The number 2,435,839 when stored in octal in the SAO's 36-bit IBM would take up 22 bits, wasting 14 bits in that machine's word. By subtracting 2,400,000 from the current Julian Day, they could represent 300 years each way in a signed 18-bit space. Since no star catalog in use by the SAO was older than 1858, that was chosen as the epoch. There was no specific mention of photographic plates in the article, but presumably, the catalogs of the late 19th century were based on photographs, giving rise to the story about dates and plates. Lest you think we'll all be using VMS for the next year 29,000 years, there are a couple of limitations to consider - after December 10th, 5941, the day of the week will be incorrectly calulated by VMS, because to get day of the week, first, LIB$DAY_OF_WEEK divides the quadword time by 600,000,000 to get number of minutes since the epoch, which it then stores in a longword. There are more than 2 billion minutes between November, 1858 and December, 5941, causing that longword to overflow. Of course, it's well known that lots of stuff will break after December 31st in the year 9999, but *nobody* will still be using VMS by then. :-) -ethan -- Ethan Dicks http://www.infinet.com/~erd/ (dicks) at (math) . (ohio-state) . (edu) sellto: postmaster@[127.0.0.1] harvestbot fodder: president@whitehouse.gov fccinfo@fcc.gov root@[127.0.0.1] ###### From: spam@lisardrock.demon.co.uk Newsgroups: alt.folklore.computers Subject: Re: Epochs in VMS (was Never mind the millenium bug....) Date: Sat, 24 Jan 1998 15:13:44 GMT Message-ID: <885654824.29133.1.nnrp-09.9e98ee68@news.demon.co.uk> References: <6achlf$1kq$1@teabag.demon.co.uk> NNTP-Posting-Host: lisardrock.demon.co.uk X-NNTP-Posting-Host: lisardrock.demon.co.uk [158.152.238.104] X-Everything: Net-Tamer V 1.09.2 Lines: 24 Path: ccw.ch!aetna.dolphins.ch!news.planetc.com!leto.ou.edu!news.onenet.net!news.oru.edu!dispose.news.demon.net!demon!news.demon.co.uk!demon!lisardrock.demon.co.uk!not-for-mail On 1998-01-24 cbh@REMOVE_THIS.teabag.demon.co.uk(ChrisHedley) said: -Malte.Uhl@neuss.netsurf.de (Malte Uhl) writes: -> They'll be using HyperVMS on Zeta processors. -I thought it was going to be UltraVMS on VAX-1100000/7800500s (CISC -is expected to be back in fashion long before then). Oh well, you -live and learn, I suppose. on the other hand, now we have OpenVMS, perhaps we'll go on to have PersonalVMS, RightInYerFaceVMS, and finally BuryMeInAYShapedCoffinVMS... and as for what it runs on? well, someday soon, computers are going to ge smart enough to correctly figure out where capitals go... at which point, we can all go back to using 6-bit character sets, and the utility of the PDP6 (on silicon, but still the same asynchronous design, just running at the equivalent of 1GHz+ - maybe digital could use strongarm technology to build it :> ) -- Communa - all at lisardrock.demon.net to be sure we read your reply, send to username `communa' Net-Tamer V 1.09.2 - Test Drive ###### From: J. Chris Hausler Newsgroups: alt.folklore.computers Subject: Re: Epochs in VMS (was Never mind the millenium bug....) Date: Tue, 27 Jan 98 01:09:09 -0500 Organization: Delphi (info@delphi.com email, 800-695-4005 voice) Lines: 10 Message-ID: References: <6achlf$1kq$1@teabag.demon.co.uk> <885654824.29133.1.nnrp-09.9e98ee68@news.demon.co.uk> NNTP-Posting-Host: 199.93.4.2 X-To: Path: ccw.ch!aetna.dolphins.ch!news.planetc.com!newsfeed.usit.net!news-spur1.maxwell.syr.edu!news.maxwell.syr.edu!cam-news-hub1.bbnplanet.com!cam-news-feed1.bbnplanet.com!news.bbnplanet.com!news.delphi.com!news writes: > -Malte.Uhl@neuss.netsurf.de (Malte Uhl) writes: > -> They'll be using HyperVMS on Zeta processors. > -I thought it was going to be UltraVMS on VAX-1100000/7800500s (CISC > -is expected to be back in fashion long before then). Oh well, you > -live and learn, I suppose. Now it looks like it will be COMPAQ's.......... Chris ###### From: Malte.Uhl@neuss.netsurf.de (Malte Uhl) Newsgroups: alt.folklore.computers Subject: Re: Epochs in VMS (was Re: Never mind the millenium bug....) References: <34c63ca2.0@news.power.net.uk> <6a5e4t$grl$1@nntp.ucs.ubc.ca> <885548084snz@tnglwood.demon.co.uk> <6aasb0$5vk$1@mathserv.mps.ohio-state.edu> Message-ID: X-Newsreader: slrn (0.9.4.3 UNIX) NNTP-Posting-Host: netsurf70.neuss.netsurf.de Date: 24 Jan 98 09:33:32 GMT Organization: "ebner & martin informationssysteme gmbh" Lines: 7 Path: ccw.ch!aetna.dolphins.ch!news.planetc.com!newsfeed.usit.net!news-spur1.maxwell.syr.edu!news.maxwell.syr.edu!newsfeed.nacamar.de!news-hh.maz.net!news.arkaden.net!Malte.Uhl In article <6aasb0$5vk$1@mathserv.mps.ohio-state.edu>, Ethan Dicks wrote: >Of course, it's well known that lots of stuff will break after December 31st >in the year 9999, but *nobody* will still be using VMS by then. :-) They'll be using HyperVMS on Zeta processors. Malte ###### From: cbh@REMOVE_THIS.teabag.demon.co.uk (Chris Hedley) Newsgroups: alt.folklore.computers Subject: Re: Epochs in VMS (was Re: Never mind the millenium bug....) Date: 24 Jan 1998 11:01:03 GMT Organization: teabag Message-ID: <6achlf$1kq$1@teabag.demon.co.uk> References: <34c63ca2.0@news.power.net.uk> <6a5e4t$grl$1@nntp.ucs.ubc.ca> <885548084snz@tnglwood.demon.co.uk> <6aasb0$5vk$1@mathserv.mps.ohio-state.edu> NNTP-Posting-Host: localhost X-NNTP-Posting-Host: teabag.demon.co.uk [193.237.4.110] Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii X-Newsreader: knews 0.9.8 Lines: 9 Path: ccw.ch!aetna.dolphins.ch!news.planetc.com!leto.ou.edu!hammer.uoregon.edu!logbridge.uoregon.edu!europa.clark.net!194.159.255.21!dispose.news.demon.net!demon!news.demon.co.uk!demon!teabag.demon.co.uk!not-for-mail In article , Malte.Uhl@neuss.netsurf.de (Malte Uhl) writes: > They'll be using HyperVMS on Zeta processors. I thought it was going to be UltraVMS on VAX-1100000/7800500s (CISC is expected to be back in fashion long before then). Oh well, you live and learn, I suppose. Chris. ###### From: lucvdv@null.net (Luc Van der Veken) Newsgroups: alt.folklore.computers Subject: Re: Epochs in VMS (was Re: Never mind the millenium bug....) Date: Sun, 25 Jan 1998 14:01:41 GMT Organization: . Lines: 32 Message-ID: <34cf24fe.7430398@news.innet.be> References: <34c63ca2.0@news.power.net.uk> <6a5e4t$grl$1@nntp.ucs.ubc.ca> <885548084snz@tnglwood.demon.co.uk> <6aasb0$5vk$1@mathserv.mps.ohio-state.edu> <6achlf$1kq$1@teabag.demon.co.uk> NNTP-Posting-Host: pmpool053-55.innet.be Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Transfer-Encoding: 7bit X-Newsreader: Forte Agent 1.5/32.451 X-No-Archive: yes Path: ccw.ch!aetna.dolphins.ch!news.planetc.com!leto.ou.edu!hammer.uoregon.edu!nntp.news.xara.net!xara.net!rill.news.pipex.net!pipex!join.news.pipex.net!pipex!krypton.inbe.net!INbe.net!not-for-mail On 24 Jan 1998 11:01:03 GMT, cbh@REMOVE_THIS.teabag.demon.co.uk (Chris Hedley) told the world, or rather subsection alt.folklore.computers of it, that: > In article , > Malte.Uhl@neuss.netsurf.de (Malte Uhl) writes: > > They'll be using HyperVMS on Zeta processors. > > I thought it was going to be UltraVMS on VAX-1100000/7800500s (CISC is > expected to be back in fashion long before then). Oh well, you live and > learn, I suppose. In 9999? More like biomechanical computers, manufactured through cloning (new systems being developed through breeding) and running Universal Sol/English as shell to the BIO-S operating system. The Internet will be using telepathic means for data transport. As we all know, after the Butler Jihad all mechanical and electronical thinking machines were banned. We're about to pollute the solar system to death by that time, after having had to flee to Mars first (terraforming Mars would have taken too long, instead genetic engineering was used to adapt human life to the conditions there). Fsck. This was supposed to become a one-liner. -- The address in the "from" field is a real address, used as a spambox. Mail there may be read, or it may not. If you want to be sure, replace the domain by innet.be