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<div class="moz-cite-prefix">On 07/04/2012 10:39 AM, Ron Frazier
(ALE) wrote:<br>
</div>
<blockquote
cite="mid:f1f62dfb-5acc-4ec4-8887-c9ac1dd0e54d@email.android.com"
type="cite">Hi all,<br>
<br>
Around the beginning of this year, I was doing quite a bit of
research into ntp and gps and eventually set up my own gps based
ntp time server in both Linux and Windows. At the end of June, a
leap second was inserted into the time sequences of the clocks on
Earth. For those that may not know what that is, the atomic clocks
are coordinated with the earth's rotation, so, for example, when
the clock says noon, the sun is always roughly overhead. However,
the earth's rotation speeds up and slows down at times.
So,sometimes, we have to tweak the clocks to match the earth
again. At the end of June, an extra second was inserted. Normally,
the seconds go 58 ... 59 ... 00. This time, they went 58 ... 59
... 60 ... 00. As it turns out, this crashed a number of servers.<br>
<br>
I find this very interesting, and somewhat scary as a potential
programmer. Since I'm thinking of learning programming again, and
since I have an interest in timekeeping, I have considered writing
a world clock program etc., to show the time in different parts of
the world. However, prior to my NTP research, I never knew about
the leap second. So, there would have been a good possibility, had
I written the program prior to this year, that my program would
have crashed as well.<br>
<br>
So, my question is, how many of you knew about leap seconds prior
to this incidence of it and prior to my describing it. If you were
writing a clock program, would you have known to account for this?<br>
</blockquote>
I did not know adding a leap second was occurring until later. I was
aware that Earth's rotation is slowing and periodically leap time
must be added to account for it. I am not sure from a purely
practical matter if it is important to add leap seconds instead of
leap hours by doing something similar to EDT/EST time change but
making it permanent.<br>
<blockquote
cite="mid:f1f62dfb-5acc-4ec4-8887-c9ac1dd0e54d@email.android.com"
type="cite">
<br>
Sincerely,<br>
<br>
Ron<br>
<br>
<br>
--<br>
<br>
Sent from my Android Acer A500 tablet with bluetooth keyboard and
K-9 Mail.<br>
Please excuse my potential brevity.<br>
<br>
(To whom it may concern. My email address has changed. Replying to
former<br>
messages prior to 03/31/12 with my personal address will go to the
wrong<br>
address. Please send all personal correspondence to the new
address.)<br>
<br>
(PS - If you email me and don't get a quick response, you might
want to<br>
call on the phone. I get about 300 emails per day from alternate
energy<br>
mailing lists and such. I don't always see new email messages very
quickly.)<br>
<br>
Ron Frazier<br>
770-205-9422 (O) Leave a message.<br>
linuxdude AT <a moz-do-not-send="true"
href="http://techstarship.com">techstarship.com</a><br>
<br>
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<br>
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</pre>
</blockquote>
<br>
<br>
<pre class="moz-signature" cols="72">--
Jay Lozier
<a class="moz-txt-link-abbreviated" href="mailto:jslozier@gmail.com">jslozier@gmail.com</a></pre>
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