[ntp:questions] Leap second to be introduced in June

Rob nomail at example.com
Mon Jan 19 17:11:15 UTC 2015


William Unruh <unruh at invalid.ca> wrote:
> On 2015-01-19, fm at fr.invalid <fm at fr.invalid> wrote:
>> William Unruh <unruh at invalid.ca> wrote:
>>> On 2015-01-19, Mike S <mikes at flatsurface.com> wrote:
>>>> On 1/18/2015 6:04 PM, William Unruh wrote:
>>>>
>>>>> UTC always has 86400 seconds per year.
>>>>
>>>> You clearly don't understand how leap seconds work. You're embarrassing 
>>>> yourself now. When there's a leap second, there are 86401 SI seconds in 
>>> 
>>> I AM clearly embarrasing myself, since 86400 is the number of seconds
>>> per SAY not year. Slight difference!
>>> 
>>> Of course there are 86401 seconds in a day including a leap second. But
>>> UTC only sees 86400. It forgets about one of them. 
>>
>> I am not sure what you mean by "sees", but I cant figure a meaning
>> that would be compatible with the fact that UTC clearly identifies 
>> 86401 seconds on the day the leap second occurs.
>
> If you ask utc how many seconds there are between now, and exactly three
> days ago, it ansers 3*86400 even if one of those days had a leap second. 
> Yes of course that leap second occurs on the day, but utc forgets that
> it did. 

You are constantly confusing the officially defined UTC time with the
implementation in computer operating systems "seconds since 1-1-1970 UTC".

That implementation neglects the presence of leap seconds.  Therefore
it has to introduce discontinuity.



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