[LEAPSECS] Future time

[Tom Van Baak]

> The problem is that all applications should care about leap seconds.

> It is a part of the time standard (UTC) that is papered over in POSIX time_t.

> This is a false partitioning, and what causes the probelms.


Warner,

"All" applications should care? It's that going a bit too far? What, are you going to ban every analog clock? Fahrenheit 86400?

UTC is simple and clearly defined and we all know the ideal/right way to handle that time scale, and by arithmetic offset, any local time. But there is also the matter of precision: different applications are looking for different levels of UTC precision. The often unstated precision requirement makes a big difference.

Where you get UTC from and how you store or display UTC are dependent on the type of application. Applications needing 1 ns precision must use a UTC(k) with circular-T, UTCr, or other real-time or post processing corrections applied. Applications needing only 1 us or 100 ns precision can get UTC via cheap GPS receivers. Applications needing 1 ms precision can use NTP. Those that need only 2 s or worse precision can get away with ignoring leap seconds, if they choose, because the resulting time-stamps are still well within the specification.

/tvb