Re: Bug: Status/Summary of slashdot leap-second crash on new years 2008-2009

David Newall
2009-01-05T19:34:37Z

Ben Goodger wrote:
> 2009/1/5 David Newall <davidn@davidnewall.com>:
>
>>> another poster said that NTP packets include information about this
>>> month's leap second, so that implies that they could change monthly.
>>>
>> Not "could change monthly" rather, "could change at any month".
>>
>> The frequency of zoneinfo updates would therefore be: every time the
>> zones you care about change; and every time there's a leap second. No
>> big effort.
>>
>
> Unfortunately, as has been pointed out, timezones are completely
> unrelated to leap seconds.
>

Zoneinfo files cater for leap seconds.

> NB. Leap seconds, positive or negative, potentially occur every six
> months (June 30 or Dec 31), but since their introduction this
> frequency has happened only once (in 1972); historically they have
> been inserted on average every 1.5 years, but there have been only two
> since 2000.

If you know in advance, you can update zoneinfo files with multiple leap
seconds.