--- /dev/null
+## downloaded 2012-02-09 from ftp://time.nist.gov/pub/leap-seconds.list by weasel
+#
+# In the following text, the symbol '#' introduces
+# a comment, which continues from that symbol until
+# the end of the line. A plain comment line has a
+# whitespace character following the comment indicator.
+# There are also special comment lines defined below.
+# A special comment will always have a non-whitespace
+# character in column 2.
+#
+# A blank line should be ignored.
+#
+# The following table shows the corrections that must
+# be applied to compute International Atomic Time (TAI)
+# from the Coordinated Universal Time (UTC) values that
+# are transmitted by almost all time services.
+#
+# The first column shows an epoch as a number of seconds
+# since 1900.0 and the second column shows the number of
+# seconds that must be added to UTC to compute TAI for
+# any timestamp at or after that epoch. The value on
+# each line is valid from the indicated initial instant
+# until the epoch given on the next one or indefinitely
+# into the future if there is no next line.
+# (The comment on each line shows the representation of
+# the corresponding initial epoch in the usual
+# day-month-year format. The epoch always begins at
+# 00:00:00 UTC on the indicated day. See Note 5 below.)
+#
+# Important notes:
+#
+# 1. Coordinated Universal Time (UTC) is often referred to
+# as Greenwich Mean Time (GMT). The GMT time scale is no
+# longer used, and the use of GMT to designate UTC is
+# discouraged.
+#
+# 2. The UTC time scale is realized by many national
+# laboratories and timing centers. Each laboratory
+# identifies its realization with its name: Thus
+# UTC(NIST), UTC(USNO), etc. The differences among
+# these different realizations are typically on the
+# order of a few nanoseconds (i.e., 0.000 000 00x s)
+# and can be ignored for many purposes. These differences
+# are tabulated in Circular T, which is published monthly
+# by the International Bureau of Weights and Measures
+# (BIPM). See www.bipm.fr for more information.
+#
+# 3. The current defintion of the relationship between UTC
+# and TAI dates from 1 January 1972. A number of different
+# time scales were in use before than epoch, and it can be
+# quite difficult to compute precise timestamps and time
+# intervals in those "prehistoric" days. For more information,
+# consult:
+#
+# The Explanatory Supplement to the Astronomical
+# Ephemeris.
+# or
+# Terry Quinn, "The BIPM and the Accurate Measurement
+# of Time," Proc. of the IEEE, Vol. 79, pp. 894-905,
+# July, 1991.
+#
+# 4. The insertion of leap seconds into UTC is currently the
+# responsibility of the International Earth Rotation Service,
+# which is located at the Paris Observatory:
+#
+# Central Bureau of IERS
+# 61, Avenue de l'Observatoire
+# 75014 Paris, France.
+#
+# Leap seconds are announced by the IERS in its Bulletin C
+#
+# See hpiers.obspm.fr or www.iers.org for more details.
+#
+# All national laboratories and timing centers use the
+# data from the BIPM and the IERS to construct their
+# local realizations of UTC.
+#
+# Although the definition also includes the possibility
+# of dropping seconds ("negative" leap seconds), this has
+# never been done and is unlikely to be necessary in the
+# foreseeable future.
+#
+# 5. If your system keeps time as the number of seconds since
+# some epoch (e.g., NTP timestamps), then the algorithm for
+# assigning a UTC time stamp to an event that happens during a positive
+# leap second is not well defined. The official name of that leap
+# second is 23:59:60, but there is no way of representing that time
+# in these systems.
+# Many systems of this type effectively stop the system clock for
+# one second during the leap second and use a time that is equivalent
+# to 23:59:59 UTC twice. For these systems, the corresponding TAI
+# timestamp would be obtained by advancing to the next entry in the
+# following table when the time equivalent to 23:59:59 UTC
+# is used for the second time. Thus the leap second which
+# occurred on 30 June 1972 at 23:59:59 UTC would have TAI
+# timestamps computed as follows:
+#
+# ...
+# 30 June 1972 23:59:59 (2287785599, first time): TAI= UTC + 10 seconds
+# 30 June 1972 23:59:60 (2287785599,second time): TAI= UTC + 11 seconds
+# 1 July 1972 00:00:00 (2287785600) TAI= UTC + 11 seconds
+# ...
+#
+# If your system realizes the leap second by repeating 00:00:00 UTC twice
+# (this is possible but not usual), then the advance to the next entry
+# in the table must occur the second time that a time equivlent to
+# 00:00:00 UTC is used. Thus, using the same example as above:
+#
+# ...
+# 30 June 1972 23:59:59 (2287785599): TAI= UTC + 10 seconds
+# 30 June 1972 23:59:60 (2287785600, first time): TAI= UTC + 10 seconds
+# 1 July 1972 00:00:00 (2287785600,second time): TAI= UTC + 11 seconds
+# ...
+#
+# in both cases the use of timestamps based on TAI produces a smooth
+# time scale with no discontinuity in the time interval.
+#
+# This complexity would not be needed for negative leap seconds (if they
+# are ever used). The UTC time would skip 23:59:59 and advance from
+# 23:59:58 to 00:00:00 in that case. The TAI offset would decrease by
+# 1 second at the same instant. This is a much easier situation to deal
+# with, since the difficulty of unambiguously representing the epoch
+# during the leap second does not arise.
+#
+# Questions or comments to:
+# Judah Levine
+# Time and Frequency Division
+# NIST
+# Boulder, Colorado
+# jlevine@boulder.nist.gov
+#
+# Last Update of leap second values: 11 January 2012
+#
+# The following line shows this last update date in NTP timestamp
+# format. This is the date on which the most recent change to
+# the leap second data was added to the file. This line can
+# be identified by the unique pair of characters in the first two
+# columns as shown below.
+#
+#$ 3535228800
+#
+# The NTP timestamps are in units of seconds since the NTP epoch,
+# which is 1900.0. The Modified Julian Day number corresponding
+# to the NTP time stamp, X, can be computed as
+#
+# X/86400 + 15020
+#
+# where the first term converts seconds to days and the second
+# term adds the MJD corresponding to 1900.0. The integer portion
+# of the result is the integer MJD for that day, and any remainder
+# is the time of day, expressed as the fraction of the day since 0
+# hours UTC. The conversion from day fraction to seconds or to
+# hours, minutes, and seconds may involve rounding or truncation,
+# depending on the method used in the computation.
+#
+# The data in this file will be updated periodically as new leap
+# seconds are announced. In addition to being entered on the line
+# above, the update time (in NTP format) will be added to the basic
+# file name leap-seconds to form the name leap-seconds.<NTP TIME>.
+# In addition, the generic name leap-seconds.list will always point to
+# the most recent version of the file.
+#
+# This update procedure will be performed only when a new leap second
+# is announced.
+#
+# The following entry specifies the expiration date of the data
+# in this file in units of seconds since 1900.0. This expiration date
+# will be changed at least twice per year whether or not a new leap
+# second is announced. These semi-annual changes will be made no
+# later than 1 June and 1 December of each year to indicate what
+# action (if any) is to be taken on 30 June and 31 December,
+# respectively. (These are the customary effective dates for new
+# leap seconds.) This expiration date will be identified by a
+# unique pair of characters in columns 1 and 2 as shown below.
+# In the unlikely event that a leap second is announced with an
+# effective date other than 30 June or 31 December, then this
+# file will be edited to include that leap second as soon as it is
+# announced or at least one month before the effective date
+# (whichever is later).
+# If an announcement by the IERS specifies that no leap second is
+# scheduled, then only the expiration date of the file will
+# be advanced to show that the information in the file is still
+# current -- the update time stamp, the data and the name of the file
+# will not change.
+#
+# Updated through IERS Bulletin C43
+# File expires on: 28 Dec 2012
+#
+#@ 3565641600
+#
+2272060800 10 # 1 Jan 1972
+2287785600 11 # 1 Jul 1972
+2303683200 12 # 1 Jan 1973
+2335219200 13 # 1 Jan 1974
+2366755200 14 # 1 Jan 1975
+2398291200 15 # 1 Jan 1976
+2429913600 16 # 1 Jan 1977
+2461449600 17 # 1 Jan 1978
+2492985600 18 # 1 Jan 1979
+2524521600 19 # 1 Jan 1980
+2571782400 20 # 1 Jul 1981
+2603318400 21 # 1 Jul 1982
+2634854400 22 # 1 Jul 1983
+2698012800 23 # 1 Jul 1985
+2776982400 24 # 1 Jan 1988
+2840140800 25 # 1 Jan 1990
+2871676800 26 # 1 Jan 1991
+2918937600 27 # 1 Jul 1992
+2950473600 28 # 1 Jul 1993
+2982009600 29 # 1 Jul 1994
+3029443200 30 # 1 Jan 1996
+3076704000 31 # 1 Jul 1997
+3124137600 32 # 1 Jan 1999
+3345062400 33 # 1 Jan 2006
+3439756800 34 # 1 Jan 2009
+3550089600 35 # 1 Jul 2012
+#
+# the following special comment contains the
+# hash value of the data in this file computed
+# use the secure hash algorithm as specified
+# by FIPS 180-1. See the files in ~/pub/sha for
+# the details of how this hash value is
+# computed. Note that the hash computation
+# ignores comments and whitespace characters
+# in data lines. It includes the NTP values
+# of both the last modification time and the
+# expiration time of the file, but not the
+# white space on those lines.
+# the hash line is also ignored in the
+# computation.
+#
+#h 914ea332 e06ddca8 7c65c64f ff579ff8 68b07a49
projects / dsa-puppet.git / commitdiff