[LEAPSECS] presentations from AAS Future of Time sessions

Dennis Ferguson dennis.c.ferguson at gmail.com
Sun Jan 12 23:31:41 EST 2014



On 12 Jan, 2014, at 15:42 , Greg Hennessy <greg.hennessy at cox.net> wrote:

> On 01/12/2014 02:47 AM, Poul-Henning Kamp wrote:

>> In message <52D20BEB.60709 at edlmax.com>, Brooks Harris writes:

>>

>>

>>> Yes, in my opinion its unfortunate they chose to use the term "UTC" in

>>> that context.

>>

>> They chose UTC because they meant UTC.

>>

>> I have this directly from multiple persons who were involved back

>> then, including Dennis Ritchie who gave me the full sordid details

>> about the early UNIX' requirement of weekly recompiles to update

>> the epoch of the timekeeping.

>

>

> If they chose UTC because they meant UTC, then why do the

> man pages refer not to UTC, but to GMT?

>

> http://cm.bell-labs.com/7thEdMan/vol1/man2.bun

>

> It sounds like you are rewriting history.


I don't think the fact that they called it "GMT" at that point tells you
anything since referring to UTC as "GMT" was pretty common in the US at
the time. Even the NBS did it. WWV voice announcements referred to the time
being transmitted as GMT from when they stopped announcing MST until 1974
even though the time was very definitely UTC by then (including the DUT1
advertisements). This site

https://soundcloud.com/shortwavemusic/sets/at-the-tone-a-little-history/

has a recording of the last announcement calling it GMT and the first calling
it UTC; it sounds like DUT1 was 0.3 seconds. The previous recording is the
announcement of the change and indicates that the time they'd been calling
GMT was in fact UTC. If the NBS's radio service was calling UTC "GMT" then
it shouldn't be surprising that computer programmer contemporaries might do
that too.

The note that goes along with the recording says that they made the change
because of CCIR complaints.

Dennis Ferguson


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