Concerning Time.TimeDiff

Matthew Donadio
Tue, 17 Jun 2003 20:58:54 -0400

John Meacham wrote:
> * But you need [leap second] tables anyway. *
> There is no correct solution which involves UTC and does not require
> tables of leap seconds.

OK, I see the problem now.

> But I recognize that such tables will not always
> be available or up to date, in which case the time might be a little
> off, but there is no way around that, such systems are just slightly
> non-conformant which is okay for many people, but we should not
> standardize on a vaugely defined incorrect semantics, rather we should
> choose the correct solution and let implementations do their best to
> conform to it on a given system.

> UNIX hacks
> around this by changing the length of a second around a leap second, so
> every timestamp when interpreted as an offset from epoch without any
> leap seconds (i.e. every minute is 60 seconds) is correct, but the
> tradeoff is that the length of a second is no longer defined and you
> can't do time arithmetic or time offsets correctly.

Are current libraries really this brain dead?  I haven't dealt with time
in almost 10 years, and always had very strict requirements (timetaging
satellite telemetry).  Sloppiness like that really surprises me.

Matthew Donadio (