[LEAPSECS] stale leap second information

[Poul-Henning Kamp]

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In message <4ABDF373-35F8-4DAE-8C64-23369DAC8F83 at noao.edu>, Rob Seaman writes:
>On Jan 17, 2015, at 1:51 PM, Steffen Nurpmeso <sdaoden at yandex.com> wrote:
>
>> Maybe it would be sufficient to start at 2014, which would avoid counting months of 42 years
>
>However the data are encoded, stored or retrieved, there will be
>a concept of operation that supports a variety of timekeeping /
>calendar use cases.  These surely include historical / retroactive
>requirements. 

If you need the historical information, you can afford the TCP
connection to IERS.

I'm focused on how NTP/PTP clients will be able to get/validate
leapsecond information efficiently and reliably.

>Unless there is an overriding value in efficient encoding, 

There is.  getaddrinfo(3) is almost always available and works
about as well as any protocol on the internet can work.

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