Chuck Harris skrev: > One of us is confused about what time_t is... I think it is > you.
I know of three different ways to interpret it. They fit different purposes. > time_t is a 32 bit (depreciated), or 64 bit integer that contains > the number of seconds since the epoch. It is not to be adjusted > for leap seconds according to POSIX, and unix convention. This is one, no two, of the interpretations I know of. > Everything to do with UTC and leap seconds is a library function > in most unixes that translates the leap second free time_t into > the leap second adjusted UTC. Exactly where? Do please tell me what the unified way of getting UTC time is. Oh, when there is a leap second it needs to give correct counting as well. Joe has in private conversations pointed out a POSIX interface which could be used. > Again, are you telling me that time_t is getting adjusted for leap > seconds? If so, when did this change? To the best of _my_ knowledge (which can be wrong) this is what is being done in practice, which is outside of the POSIX standard, but has the effect that 00:00:00 always midnight, which POSIX needs. This is a third interpretation... If somebody (say PHK) got out and slapped my face and say this is a total misunderstanding, this is pretty good after all. If this practice does exist, then we still have three interpretations and they are in conflict with each other even after giving up on introducing leap seconds. So we have two or three interpretation of the POSIX timescale, one with pure SI seconds, one with rubber seconds up till 1972-00-00T00:00:00Z and then SI seconds and a third which is like the second but re-aligned on each leap second event so that midnights match. This is only an issue if the POSIX scale is under external control. And yes, do tell me how I get UTC on all platforms. Regardless, this just shows how complex the issue is. There seems that there is no "correct" interpretation that everyone can agree with as a basis. If there is I'll be much happier and go away a bit wiser. Cheers, Magnus _______________________________________________ time-nuts mailing list -- [email protected] To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
