[LEAPSECS] presentations from AAS Future of Time sessions

[Tony Finch]

Brooks Harris <brooks at edlmax.com> wrote:


> You are saying that UTC as a term for the adjusted timescale existed as

> the process of time-keeping in computers began and they intended

> computers to reflect "civil time" even if the details of exactly how to

> do that hadn't been worked out. "Modern" UTC, UTC with Leap Seconds

> after 1972, hadn't yet started, so it wasn't considered.


The development was concurrent, not sequential. Unix 1st and 2nd edition
had a 1971 epoch and 1/60th second resolution. 3rd edition moved the epoch
to 1972. (The overall manual was dated Feb 1973 and the page for time(2)
was dated March 1972.) The 4th edition introduced modern Unix time.
(Overall manual dated November 1973, and time(2) dated August 1973.)

So UTC had started but wasn't available to the computers that Unix was
running on.

Tony.
-- 
f.anthony.n.finch  <dot at dotat.at>  http://dotat.at/
Forties, Cromarty: East, veering southeast, 4 or 5, occasionally 6 at first.
Rough, becoming slight or moderate. Showers, rain at first. Moderate or good,
occasionally poor at first.