Re: Monitoring the leap second tonight

Ulrich Windl <Ulrich.Windl@xxxxxxxxxxxxxxxxxxxx> writes:
|> > Sun Jan 1 00:59:57 CET 2006
|> > Sun Jan 1 00:59:58 CET 2006
|> > Sun Jan 1 00:59:59 CET 2006
|> > Sun Jan 1 00:59:59 CET 2006 <=== leap second occured
|>
|> Shouldn't the output have been "Sun Jan 1 00:59:60 CET 2006"?

IMHO, there are pretty strong arguments that attempting to implement a UTC
leap this way (i.e., showing the 60 or even repeating the 59) on a computer
clock could be called an undesireable and potentially disruptive engineering
practice. Remember that ITU-R TF.460 was written for pulse-per-second
timecodes, where this makes sense, and not for operating system APIs,
network protocols, etc.

I think, the ITU-R TF.460 idea of a second labeled 60 should not be
implemented in these areas without very careful thinking about the
consequences. There are much less troublesome conventions possible
for performing the 1-second UTC adjustment in a computer clock:

http://www.ietf.org/internet-drafts/draft-kuhn-leapsecond-00.txt

Markus

--
Markus Kuhn, Computer Laboratory, University of Cambridge
http://www.cl.cam.ac.uk/~mgk25/ || CB3 0FD, Great Britain
.

Relevant Pages

  • Re: Inserting Calendar.Time in a database
    ... >> So should UTC clock. ... > appropriate time base - and we certainly don't want to insist that every ... That you can view a clock reading as ... quite often the precision required for clock synchronization of nodes ...
    (comp.lang.ada)
  • Re: To synchronize system time witn NTP-server with no winter time shift whole year - how to
    ... On a Linux computer, the internal clock is almost certainly *NOT* UTC, ... rather it is "seconds since Unix Epoch", ... TAI has its own Epoch back in the late '50s or early '60s. ...
    (Debian-User)
  • Re: Best Practices on setting clock?
    ... Do i need to set the CMOS clock to UTC and the actual OS or diplayed ... time would be LOCAL TIME according to my local Time Zone? ...
    (comp.unix.admin)
  • Re: TOD Clock the same as the BIOS clock in PCs?
    ... I have been told that the TOD clock similar to the RTC/CMOS clock ... do they log their times in UTC time also? ... But, do they actually display the LOCAL TIME on the VTAM, ...
    (bit.listserv.ibm-main)
  • Re: [SLE] Daylight Saving time change?
    ... clock and can be read with "hwclock -r". ... and the result is presented to the system for use: display, ... correct UTC might be 3am but you can have it set to 9pm. ... All the system will do is apply local time zone offsets from its ...
    (SuSE)