herrickd@iccgcc.decnet.ab.com (11/30/90)
In article <847@Snoopy.Logicon.COM>, Makey@Snoopy.Logicon.COM (Jeff Makey) writes: > In article <37@bootsie.UUCP> olson@endor.harvard.edu (Eric Olson) writes: >>The _real_ problem with storing dates as "number of seconds since Jan 1, 1970" >>is that sometime in the year 2106, all the dates are gonna wrap around to >>1970 again! > > One of the few things that VAX/VMS does better than any other Some companies learn from their experiences. > operating system I am aware of is its range of dates. Zero is > 17 November 1858, it won't overflow for more than 10,000 years, and > the precision is 100 nanoseconds (better than current hardware can > provide). Unfortunately, DEC more than compensated for this by > omitting any concept of time zones or daylight savings time. But perhaps not enough. The experience in question. PDP-10 has 36 bit words and convenient hardware manipulations of half-words (18 bit objects). They allocated a half word to hold date and time in directory entries and elsewhere. Before I got near one, the eighteen bits had overflowed and there was an extension to the directory entry holding lots of useful stuff, including another half word of date time information. Having half a date over here and the other half over there looks very strange. dan herrick > > :: Jeff Makey > > Department of Tautological Pleonasms and Superfluous Redundancies Department > Disclaimer: All opinions are strictly those of the author. > Domain: Makey@Logicon.COM UUCP: {ucsd,nosc}!snoopy!Makey