[ntp:hackers] Leap second support in versions prior to 4.2.6

Mike S mikes at flatsurface.com
Sun Jun 3 22:59:55 UTC 2012


On 6/2/2012 2:29 PM, Dave Hart wrote:
We know there are
> kernels out there that will insert a requested leap second without
> regard to date (specifically, on other than the 4 possible insertion
> dates each year).

Don't make the incorrect assumption, and please don't codify it, that 
there are only 4 possible leap second dates per year. It's not clear 
where you got that impression. To date, all leap seconds have occurred 
on either 30Jun or 31Dec. If more are needed, there is a _preference_ 
for Mar and Sep, but they can occur during _any_ month.

"A positive or negative leap-second should be the last second of a UTC 
month, but first preference should be given to the end of December and 
June, and second preference to the end of March and September." -
ITU-R Recommendation TF.460-4


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