[LEAPSECS] Future time

[Warner Losh]

On Jan 19, 2014, at 8:34 AM, Daniel R. Tobias wrote:


> On 18 Jan 2014 at 19:51, Warner Losh wrote:

> 

>> Of course, the 6 month window does make it impossible to compute a time_t for a known

>> interval into the future that's longer than 6 months away...

> 

> What are the applications that actually need to schedule events more 

> than 6 months in the future that need to be precisely synchronized to 

> civil time at a resolution of under a second? Gee, I might miss the 

> plane for the airline reservation I made 7 months in advance if I 

> show up one second late! (Actually, both myself and the airline, if 

> we care about this level of detail, will have adjusted our 

> clocks/watches by flight day, including any leap seconds in the 

> interim, and I'll be right on time.)


It is this kind of scorn and derision that makes it hard to actually come up with a solution. Sometimes you don't find out about leap seconds that far in advance. The key is that having leap seconds not known makes computation of future times as a count of seconds impossible. It might not matter "much" but the not caring about all the details has contributed to very few things actually getting leap seconds right. It is just a second, right?

Warner