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\/ \/ \/ \/ \/ \/ \/ \/ \/ \/ \/ \/ \/ \/ \/ \/ \/ \/ \/ \/ \/ \/ \/ \/ \/ From: Bob Armstrong97/11/05 15:49 Subject: Y2K Info To: adam@westergaard.com Adam , Here are copies of the notes on Y2K I sent John . ------------------------------------------------------------------------- ============================: TUE.MAR,970311 :============================ To: > INTERNET:john@westergaard.com Subject: Y2K and other overflows John & Emile , | DDT , LOC |>| TUE.MAR,970311,13:27 NYC -5 + 0 In settling on a web broker ... ( I have settled on ... partly because its on my friend JayWhipple3`s PortfolioAccountingWorldWideSystem , now a part of CheckFree . ) I recently perused your site . I`ve never been overly impressed by the year 2000 problem . The reason I ( and Jay ) live in APL ( the name of his original company is Security APL ) is because it is the most abstract , and therefore restructurable , of languages . That`s why its main market is very hi level financial systems . For instance , one old friend ( and early adopter of CoSy back in the `80s ) is a leading actuary in workperson`s compensation reinsurance where the timescales are scores of years and the action starts several sigma low in frequency and hi in $$$ . APL systems are much more prone to the sort of problem discussed in ' The Next Date Crisis and the Ones After That ' by Robert L. Glass in January`s Communications of the ACM . Luckily , the article is on the web at http://www.acm.org/cacm/JAN97/pptext.htm . Ironically , I just encountered my own Y2K bug . It`s young . I made it in 1995 . I was generating DayLines for my future MidWinter CoSy gatherings to see what days the party would be falling and I saw the following : ================: THU.FEB,990204 :================= ================: FRI.FEB, 204 :================= ++++++++++++++++: SUN.FEB, 10204 :+++++++++++++++++ obviously caused by dropped leading 0s . [ps] In simplifying my timestamp to the current form , I made the function TS is { 100 base 100 modulo 5 take RA } to simply pack vector time stamps in the form 2000 2 4 15 13 55 999 into a single floating point number accurate to the minute . The bug clearly comes because leading 0s are lost . I ended up replacing this definition with TS is { ( , transpose 10 10 represent 5 take RA ) pik DIGITS } which returns a correct character string . I searched all the 1111 verbs which currently compose CoSy to check that TS is not used anywhere other than in DDTFMT which underlies the DayDateTime function you see used above . While I was at it , you`ll see below I finally added the local time zone offset to DDT . I must admit , I spent more time on this than I expected , and you can see that in CoSy/APL the actual amount of code changed is small . But it has to be well considered . If you have any questions or comments about all this , let me know . Incedentally , now that I am finally wraping up family related business in Illinois , I am actively turning to marketing CoSy as it is , and bringing together the people and resources to take it where it can go . Which is to displace Microsoft`s terminally complex environment [ designed ] for Children who run Corporations . | DDT |>| TUE.MAR,970311,16:3-5 -- BobA -- BobArmstrong CoherentSystems 212-285-1864 ø X:-732-0244 http://cosy.com 42 PeckSlip 4B | NYC NY 10038 bob@cosy.com / [ps] : This bug is more pernicious in terms of effect because it breaks the timestamp into 2 pieces since SPace is the fundamental delimiter in CoSy . |17:11| ============================: TUE.OCT,971021 :============================ From: Bob Armstrong 10:58 Subject: Y2K starting 971102 To: John Westergaard John , Here`s a Y2K problem of the arbitrary sort I sent you info about back on TUE.MAR,970311 . It`s on page 8 of the Oct. 20 Electronic Engineering Times . You can access it by the URLs below : http://cmp-pub1.web.cerf.net/en/sbin/iarecord?NS-search-set=/344cb/aaaa003q14 cb5a0&NS-doc-offset=0&NS-adv-search=0& http://www.techweb.com/se/techsearch.cgi?action=View&VdkVgwKey=%2E%2E%2F%2E%2 E%2F%2E%2E%2F%2E%2E%2F%2E%2E%2Fservices%2Fdata%2Fsearch%2Fdata%2F1997%5F%5F%5 B28428%5D&DocOffset=1&DocsFound=1&QueryZip=apollo+bug&SourceQueryZip=+%3Cand% 3E+%28%27EET%27+%3Cin%3E+pub%29+%3Cand%3E+%28issuedate+%3E%3D+9%2F1%2F1997%29 +%3Cand%3E+%28issuedate+%3C%3D+10%2F31%2F1997%29&Collection=coll1997&Collecti on=tw%5Fcurrent&Collection=tw%5Fdaily&Collection=collinv&ViewTemplate=cmpview %2Ehts&&publication=EET" Or more simply go to : http://pubsys.cmp.com/eet/news/search/print.html and search for 'Apollo bug' . Here`s the start of it : HP, Mentor can't agree on fix for Nov. 2 Apollo bug By Richard Goering Wilsonville, Ore. - Mentor Graphics customers still running Apollo Domain workstations from Hewlett-Packard Co. will get a nasty surprise at precisely 14:59 Greenwich Mean Time Nov. 2, when the real-time clock will increment in a way that may cause a catastrophic system crash. And Mentor and HP offer conflicting advice on what to do about this early "Year 2000" problem. Apollo workstations use a 32-bit real-time clock, and on Nov. 2 it will increment so that the 32nd bit is set. Some computer operations evaluate that bit as a negative number, causing serious problems when an application tries to compare time stamps from before and after. Documentation at HP's Web site (www.hp.com/go/vintagesw) says the system may "panic" or hang, in which case "the file system will be at risk." ============================: MON.DEC,971208 :============================ From: Bob Armstrong 09:40 Subject: Date overflows To: "john@westergaard.com" -- BobA -- BobArmstrong CoherentSystems 212-285-1864 hf X:-732-0244 http://cosy.com 42 PeckSlip 4B | NYC NY 10038 bob@cosy.comCC: Adam Kaplan John & Adam , I happened to pull up the following when looking at http://www.wrs.com , Wind River Systems , an embedded systems operating system provider . Note there are 3 overflow dates they warn about other than Y2K . -- BobA -- http://Cosy.com --------------------------------------------------------------------- To our customers: Wind River's Tornado development environment, including the VxWorks real-time operating system, will not be affected by the rollover from 1999 to the year 2000. The VxWorks system clock itself is simply a count of ticks, and there is no conversion between it and calendar time. The concept of calendar time is only applicable to file system-related functions. In VxWorks, real calendar time is maintained by the user and provided to Wind River's MS-DOS-compatible (dosFsLib) and RT-11 (rt11FsLib) file system libraries through call-outs or specific time-setting functions. Wind River products use the following timing specifications: ANSI C--VxWorks uses ANSI C time specifications, which are "year 2000 compliant." ANSI C will have its own rollover in the year 2038, when there will be 31 bits worth of seconds since 1/1/1970 to deal with. There are some plans within ANSI and/or POSIX to handle this rollover via extensions but, as of yet, no proposals have been formally adopted. dosFsLib--Wind River's dosFs file system is year 2000 compliant. Like MS-DOS, dosFs encoding can handle dates through 12/31/2099. rt11FsLib--The RT-11 file system is also year 2000 compliant, but can only handle dates through 12/31/2003. Wind River does not plan to support rt11FsLib beyond the year 2000. - It`s that 2003 date which is in the sort of embedded systems Ed Yardeni is concerned about .