ietf-nntp Section 11.5 - NEWNEWS

Charles Lindsey chl at clw.cs.man.ac.uk
Mon Nov 20 06:30:20 PST 2000


In <20001118154625.D34936 at demon.net> "Clive D.W. Feather" <clive at demon.net> writes:


>Charles Lindsey said:
>> May I suggest
>> 
>> + The date and time are given in the server's approximation to UTC
>> + (commonly referred to as GMT).

>UTC is *not* GMT. Or anywhere near it. This is the source of the problem.

Eh? Surely by your description UTC and GMT should be within a second of
each other (except that noone at Greenwich is calculating GMT any more -
but I presume someone somewhere is running a transit telescope in order to
decide when leap seconds are needed).

>But, the number of seconds in a UTC day varies - introducing a programming
>problem - and that variation cannot be predicted in the long term - leap
>seconds are only announced a month or two ahead.

Since your typical server is likely to be a few seconds out, and internet
protocols should make allowance for this, the only sensible thing is for
the Internet to run on a fictitious "POSIX time" in which each year
contains exactly 365*24*60*60 seconds (plus extra in leap years), which is
kept broadly in line with UTC by means of every server syncing itself
whenever it (or its admins) sees fit. That is essentially what happens
currently, and we have to live with it.

-- 
Charles H. Lindsey ---------At Home, doing my own thing------------------------
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