nanog mailing list archives
Re: F-ckin Leap Seconds, how do they work?
From: Steven Bellovin <smb () cs columbia edu>
Date: Thu, 5 Jul 2012 11:29:11 -0400
On Jul 5, 2012, at 10:49 48AM, Peter Lothberg wrote:
On one of my BSD boxes. /usr/src/share/zoneinfo/leapseconds, I see no "-"No, but they're allowed; see Figure 9 of RFC 5905:Steve, I commented that it was stated that we where doing both positive and negative corrections. Only positive corrections have been made, and yes, negative are possible. I pointed out in a previous post that we can count 57, 58, 00 or 57, 58, 59, 00 or 57, 58, 59, 60, 00. And actually, this is the only thing operating-systems and applications need to be capable to handle to make it a non_issue.
Fair enough.
LI Leap Indicator (leap): 2-bit integer warning of an impending leap second to be inserted or deleted in the last minute of the current month with values defined in Figure 9. +-------+----------------------------------------+ | Value | Meaning | +-------+----------------------------------------+ | 0 | no warning | | 1 | last minute of the day has 61 seconds | | 2 | last minute of the day has 59 seconds | | 3 | unknown (clock unsynchronized) | +-------+----------------------------------------+That's NTP packet format, used to implemment NTP's represenation of UTC, but not the definition of UTC... (What do I do if I receive a packet with "3".) Or better, all the UTC(k) are free-running and the (old) recomenadtion was to try to keep them within 1us, is that unsyncronized -:) And ooops, I did not catch that before, should it not say "last minute of the month"?
The text as I copied it is certainly not consistent...
If I remember right the posix standard don't allow "60" in seconds... -Peter
--Steve Bellovin, https://www.cs.columbia.edu/~smb
Current thread:
- Re: F-ckin Leap Seconds, how do they work?, (continued)
- Re: F-ckin Leap Seconds, how do they work? Peter Lothberg (Jul 03)
- Re: F-ckin Leap Seconds, how do they work? Tony Finch (Jul 03)
- Re: F-ckin Leap Seconds, how do they work? Eugen Leitl (Jul 03)
- Re: F-ckin Leap Seconds, how do they work? Leo Bicknell (Jul 03)
- Re: F-ckin Leap Seconds, how do they work? Jay Ashworth (Jul 03)
- Re: F-ckin Leap Seconds, how do they work? Peter Lothberg (Jul 05)
- Re: F-ckin Leap Seconds, how do they work? valdis . kletnieks (Jul 03)
- Re: F-ckin Leap Seconds, how do they work? Peter Lothberg (Jul 03)
- Re: F-ckin Leap Seconds, how do they work? Steven Bellovin (Jul 03)
- Re: F-ckin Leap Seconds, how do they work? Peter Lothberg (Jul 05)
- Re: F-ckin Leap Seconds, how do they work? Steven Bellovin (Jul 05)
- Re: F-ckin Leap Seconds, how do they work? Tony Finch (Jul 03)
- Re: F-ckin Leap Seconds, how do they work? Owen DeLong (Jul 03)
- Re: F-ckin Leap Seconds, how do they work? Brett Frankenberger (Jul 04)
- Re: F-ckin Leap Seconds, how do they work? valdis . kletnieks (Jul 04)
- Re: F-ckin Leap Seconds, how do they work? Brett Frankenberger (Jul 04)
- Re: F-ckin Leap Seconds, how do they work? valdis . kletnieks (Jul 04)
- Re: F-ckin Leap Seconds, how do they work? William Herrin (Jul 04)
- Re: F-ckin Leap Seconds, how do they work? Jason Hellenthal (Jul 04)
- Re: F-ckin Leap Seconds, how do they work? George Herbert (Jul 04)
- Re: F-ckin Leap Seconds, how do they work? Jimmy Hess (Jul 04)