On Aug 1, 2011, at 5:30 PM, Russ Allbery wrote: > . . . One of the interesting questions is whether conversion of > the first and last calendar times above are, when represented as > timestamps, one second apart or two seconds apart. > > Note that, in POSIX, they're one second apart, because POSIX time contains > no leap seconds by definition (which means that it's not really possible > to accurately represent those dates). > > On UNIX systems, using mktime on those dates will generally convert as > follows: > > 1972-06-30 23:59:59 78821999 > 1972-06-30 23:59:60 78822000 > 1972-07-01 00:00:00 78822000 > > There's not really a "right" answer here; we just need to say what the > answer is.
The last paragraph says it, both w/r/t the POSIX issues above and the various other time issues discussed in this thread. We don't need to be absolutely right*, nor do we necessarily need to be fully in agreement with any other vendor or standards system. We just need to say what we are doing. I proposed we be broken in the same way POSIX is broken, rather than being any other brand of broken or inventing our own. :-) Steve * IMHO 'absolutely right' would involved knowing what is right, and presenting to all the other broken implementations their expected broken data. The former is beyond our scope and abilities, the latter . . . well, that way lies madness. Let's face it, 99.99% of the time all we're talking about are filesystem timestamps. If someone wants to touch a file with the date Sept 10 1752 and not specify anything else about how to interpret that date, they deserve the wrongness they get. And anybody who's doing work where leap seconds and calendar type transitions matter is not doing it using POSIX, Windows, or any other OS-time representation.** ** No, I have no freaking idea what they're using._______________________________________________ AFS3-standardization mailing list [email protected] http://lists.openafs.org/mailman/listinfo/afs3-standardization
