diff options
Diffstat (limited to 'contrib/tzdata/leapseconds')
| -rw-r--r-- | contrib/tzdata/leapseconds | 41 |
1 files changed, 22 insertions, 19 deletions
diff --git a/contrib/tzdata/leapseconds b/contrib/tzdata/leapseconds index 886ae273e159..7808df8f894f 100644 --- a/contrib/tzdata/leapseconds +++ b/contrib/tzdata/leapseconds @@ -3,36 +3,39 @@ # This file is in the public domain. # This file is generated automatically from the data in the public-domain -# leap-seconds.list file, which can be copied from +# NIST format leap-seconds.list file, which can be copied from # <ftp://ftp.nist.gov/pub/time/leap-seconds.list> -# or <ftp://ftp.boulder.nist.gov/pub/time/leap-seconds.list> -# or <ftp://tycho.usno.navy.mil/pub/ntp/leap-seconds.list>. +# or <ftp://ftp.boulder.nist.gov/pub/time/leap-seconds.list>. # For more about leap-seconds.list, please see # The NTP Timescale and Leap Seconds # <https://www.eecis.udel.edu/~mills/leap.html>. -# The International Earth Rotation and Reference Systems Service +# The rules for leap seconds are specified in Annex 1 (Time scales) of: +# Standard-frequency and time-signal emissions. +# International Telecommunication Union - Radiocommunication Sector +# (ITU-R) Recommendation TF.460-6 (02/2002) +# <https://www.itu.int/rec/R-REC-TF.460-6-200202-I/>. +# The International Earth Rotation and Reference Systems Service (IERS) # periodically uses leap seconds to keep UTC to within 0.9 s of UT1 -# (which measures the true angular orientation of the earth in space) +# (a proxy for Earth's angle in space as measured by astronomers) # and publishes leap second data in a copyrighted file # <https://hpiers.obspm.fr/iers/bul/bulc/Leap_Second.dat>. # See: Levine J. Coordinated Universal Time and the leap second. # URSI Radio Sci Bull. 2016;89(4):30-6. doi:10.23919/URSIRSB.2016.7909995 # <https://ieeexplore.ieee.org/document/7909995>. -# There were no leap seconds before 1972, because the official mechanism -# accounting for the discrepancy between atomic time and the earth's rotation -# did not exist. The first ("1 Jan 1972") data line in leap-seconds.list +# There were no leap seconds before 1972, as no official mechanism +# accounted for the discrepancy between atomic time (TAI) and the earth's +# rotation. The first ("1 Jan 1972") data line in leap-seconds.list # does not denote a leap second; it denotes the start of the current definition # of UTC. -# The correction (+ or -) is made at the given time, so lines -# will typically look like: -# Leap YEAR MON DAY 23:59:60 + R/S -# or -# Leap YEAR MON DAY 23:59:59 - R/S - -# If the leap second is Rolling (R) the given time is local time (unused here). +# All leap-seconds are Stationary (S) at the given UTC time. +# The correction (+ or -) is made at the given time, so in the unlikely +# event of a negative leap second, a line would look like this: +# Leap YEAR MON DAY 23:59:59 - S +# Typical lines look like this: +# Leap YEAR MON DAY 23:59:60 + S Leap 1972 Jun 30 23:59:60 + S Leap 1972 Dec 31 23:59:60 + S Leap 1973 Dec 31 23:59:60 + S @@ -62,8 +65,8 @@ Leap 2015 Jun 30 23:59:60 + S Leap 2016 Dec 31 23:59:60 + S # POSIX timestamps for the data in this file: -#updated 1467936000 -#expires 1577491200 +#updated 1467936000 (2016-07-08 00:00:00 UTC) +#expires 1593302400 (2020-06-28 00:00:00 UTC) -# Updated through IERS Bulletin C57 -# File expires on: 28 December 2019 +# Updated through IERS Bulletin C58 +# File expires on: 28 June 2020 |