Sync zoneinfo database with tzdata2009h from elsie.
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1# <pre>
2# @(#)leapseconds 8.8
3# This file is in the public domain, so clarified as of
4# 2009-05-17 by Arthur David Olson.
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5
6# Allowance for leapseconds added to each timezone file.
7
8# The International Earth Rotation Service periodically uses leap seconds
9# to keep UTC to within 0.9 s of UT1
10# (which measures the true angular orientation of the earth in space); see
11# Terry J Quinn, The BIPM and the accurate measure of time,
12# Proc IEEE 79, 7 (July 1991), 894-905.
13# There were no leap seconds before 1972, because the official mechanism
14# accounting for the discrepancy between atomic time and the earth's rotation
15# did not exist until the early 1970s.
16
17# The correction (+ or -) is made at the given time, so lines
18# will typically look like:
19# Leap YEAR MON DAY 23:59:60 + R/S
20# or
21# Leap YEAR MON DAY 23:59:59 - R/S
22
23# If the leapsecond is Rolling (R) the given time is local time
24# If the leapsecond is Stationary (S) the given time is UTC
25
26# Leap YEAR MONTH DAY HH:MM:SS CORR R/S
27Leap 1972 Jun 30 23:59:60 + S
28Leap 1972 Dec 31 23:59:60 + S
29Leap 1973 Dec 31 23:59:60 + S
30Leap 1974 Dec 31 23:59:60 + S
31Leap 1975 Dec 31 23:59:60 + S
32Leap 1976 Dec 31 23:59:60 + S
33Leap 1977 Dec 31 23:59:60 + S
34Leap 1978 Dec 31 23:59:60 + S
35Leap 1979 Dec 31 23:59:60 + S
36Leap 1981 Jun 30 23:59:60 + S
37Leap 1982 Jun 30 23:59:60 + S
38Leap 1983 Jun 30 23:59:60 + S
39Leap 1985 Jun 30 23:59:60 + S
40Leap 1987 Dec 31 23:59:60 + S
41Leap 1989 Dec 31 23:59:60 + S
42Leap 1990 Dec 31 23:59:60 + S
43Leap 1992 Jun 30 23:59:60 + S
44Leap 1993 Jun 30 23:59:60 + S
45Leap 1994 Jun 30 23:59:60 + S
46Leap 1995 Dec 31 23:59:60 + S
47Leap 1997 Jun 30 23:59:60 + S
48Leap 1998 Dec 31 23:59:60 + S
b402be54 49Leap 2005 Dec 31 23:59:60 + S
3f249718 50Leap 2008 Dec 31 23:59:60 + S
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0e49ec84 52# INTERNATIONAL EARTH ROTATION AND REFERENCE SYSTEMS SERVICE (IERS)
a6282357 53#
9ffe4b14 54# SERVICE INTERNATIONAL DE LA ROTATION TERRESTRE ET DES SYSTEMES DE REFERENCE
8393cd87 55#
9ffe4b14 56# SERVICE DE LA ROTATION TERRESTRE
3f249718 57# OBSERVATOIRE DE PARIS
9ffe4b14 58# 61, Av. de l'Observatoire 75014 PARIS (France)
a3c830a8 59# Tel. : 33 (0) 1 40 51 22 29
0e49ec84 60# FAX : 33 (0) 1 40 51 22 91
a3c830a8 61# Internet : services.iers@obspm.fr
0e49ec84 62#
a3c830a8 63# Paris, 15 January 2009
8393cd87 64#
a3c830a8 65# Bulletin C 37
8393cd87 66#
3f249718 67# To authorities responsible
0e49ec84 68# for the measurement and
3f249718 69# distribution of time
8393cd87 70#
a3c830a8 71# INFORMATION ON UTC - TAI
0e49ec84 72#
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73# NO positive leap second will be introduced at the end of June 2009.
74# The difference between Coordinated Universal Time UTC and the
75# International Atomic Time TAI is :
0e49ec84 76#
a3c830a8 77# from 2009 January 1, 0h UTC, until further notice : UTC-TAI = -34 s
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78#
79# Leap seconds can be introduced in UTC at the end of the months of December
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80# or June, depending on the evolution of UT1-TAI. Bulletin C is mailed every
81# six months, either to announce a time step in UTC, or to confirm that there
0e49ec84 82# will be no time step at the next possible date.
8393cd87 83#
0e49ec84 84# Daniel GAMBIS
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85# Head
86# Earth Orientation Center of the IERS
0e49ec84 87# Observatoire de Paris, France