| 1 |
# Generate the 'leapseconds' file from 'leap-seconds.list'. |
| 2 |
|
| 3 |
# This file is in the public domain. |
| 4 |
|
| 5 |
BEGIN { |
| 6 |
print "# Allowance for leap seconds added to each time zone file." |
| 7 |
print "" |
| 8 |
print "# This file is in the public domain." |
| 9 |
print "" |
| 10 |
print "# This file is generated automatically from the data in the public-domain" |
| 11 |
print "# leap-seconds.list file available from most NIST time servers." |
| 12 |
print "# If the URL <ftp://time.nist.gov/pub/leap-seconds.list> does not work," |
| 13 |
print "# you should be able to pick up leap-seconds.list from a secondary NIST server." |
| 14 |
print "# For more about leap-seconds.list, please see" |
| 15 |
print "# The NTP Timescale and Leap Seconds" |
| 16 |
print "# http://www.eecis.udel.edu/~mills/leap.html" |
| 17 |
print "" |
| 18 |
print "# The International Earth Rotation and Reference Systems Service" |
| 19 |
print "# periodically uses leap seconds to keep UTC to within 0.9 s of UT1" |
| 20 |
print "# (which measures the true angular orientation of the earth in space); see" |
| 21 |
print "# Terry J Quinn, The BIPM and the accurate measure of time," |
| 22 |
print "# Proc IEEE 79, 7 (July 1991), 894-905 <http://dx.doi.org/10.1109/5.84965>." |
| 23 |
print "# There were no leap seconds before 1972, because the official mechanism" |
| 24 |
print "# accounting for the discrepancy between atomic time and the earth's rotation" |
| 25 |
print "# did not exist until the early 1970s." |
| 26 |
print "" |
| 27 |
print "# The correction (+ or -) is made at the given time, so lines" |
| 28 |
print "# will typically look like:" |
| 29 |
print "# Leap YEAR MON DAY 23:59:60 + R/S" |
| 30 |
print "# or" |
| 31 |
print "# Leap YEAR MON DAY 23:59:59 - R/S" |
| 32 |
print "" |
| 33 |
print "# If the leapsecond is Rolling (R) the given time is local time." |
| 34 |
print "# If the leapsecond is Stationary (S) the given time is UTC." |
| 35 |
print "" |
| 36 |
print "# Leap YEAR MONTH DAY HH:MM:SS CORR R/S" |
| 37 |
} |
| 38 |
|
| 39 |
/^ *$/ { next } |
| 40 |
|
| 41 |
/^#\tUpdated through/ || /^#\tFile expires on:/ { |
| 42 |
last_lines = last_lines $0 "\n" |
| 43 |
} |
| 44 |
|
| 45 |
/^#/ { next } |
| 46 |
|
| 47 |
{ |
| 48 |
NTP_timestamp = $1 |
| 49 |
TAI_minus_UTC = $2 |
| 50 |
hash_mark = $3 |
| 51 |
one = $4 |
| 52 |
month = $5 |
| 53 |
year = $6 |
| 54 |
if (old_TAI_minus_UTC) { |
| 55 |
if (old_TAI_minus_UTC < TAI_minus_UTC) { |
| 56 |
sign = "23:59:60\t+" |
| 57 |
} else { |
| 58 |
sign = "23:59:59\t-" |
| 59 |
} |
| 60 |
if (month == "Jan") { |
| 61 |
year--; |
| 62 |
month = "Dec"; |
| 63 |
day = 31 |
| 64 |
} else if (month == "Jul") { |
| 65 |
month = "Jun"; |
| 66 |
day = 30 |
| 67 |
} |
| 68 |
printf "Leap\t%s\t%s\t%s\t%s\tS\n", year, month, day, sign |
| 69 |
} |
| 70 |
old_TAI_minus_UTC = TAI_minus_UTC |
| 71 |
} |
| 72 |
|
| 73 |
END { |
| 74 |
printf "\n%s", last_lines |
| 75 |
} |
