[ntp:questions] Unix time_t hits 1.5Gs early Friday UTC

Brian Inglis Brian.Inglis at SystematicSw.ab.ca
Thu Jul 13 03:17:28 UTC 2017


Unix time_t will hit 1 500 000 000 at 2017 Jul 14 Fri 02:40:00+0000
which is Thursday evening in North America:

$ for city in Vancouver Edmonton Regina Winnipeg Toronto Halifax St_Johns; do
TZ=America/$city date -d at 1500000000 +%c\ %Z; done
2017 Jul 13 Thu 19:40:00 PDT
2017 Jul 13 Thu 20:40:00 MDT
2017 Jul 13 Thu 20:40:00 CST
2017 Jul 13 Thu 21:40:00 CDT
2017 Jul 13 Thu 22:40:00 EDT
2017 Jul 13 Thu 23:40:00 ADT
2017 Jul 14 Fri 00:10:00 NDT

and on some other time scales, which may not be aligned to UTC:

$ gpstime.sh @1500000000
2017 Jul 14 Fri 02:40:00+0000  JD 2457948.611111  MJD 57948.111111  ToD 9599
NTP 3708988800  Unix 1500000000  TAI-UTC 37  TAI-GPS 19  GPS-UTC 18
GPS We 1957  Cy 1 Wn 933  Wa 165 ToW 441618  DoW 5 ToD 9618

As usual there will be some Europeans staying up late to celebrate and party.

Unix time won't hit 1.5Gis until:

$ gpstime.sh @`bc <<< 2^30*3/2`
2021 Jan 14 Thu 08:25:36+0000  JD 2459228.851111  MJD 59228.351111  ToD 30336
NTP 3819601536  Unix 1610612736  TAI-UTC 37 TAI-GPS 19 GPS-UTC 18
GPS We 2140  Cy 2 Wn 92  Wa 92 ToW 375954  DoW 4 ToD 30354

NTP time won't hit 4Gs until:

$ gpstime.sh @`bc <<< 4*10^9-3708988800+1500000000`
2026 Oct 03 Sat 07:06:40+0000  JD 2461316.796296  MJD 61316.296296  ToD 25600
NTP 4000000000  Unix 1791011200  TAI-UTC 37 TAI-GPS 19 GPS-UTC 18
GPS We 2438  Cy 2 Wn 390  Wa 134 ToW 544018  DoW 6 ToD 25618

and will hit 4Gis at:

$ gpstime.sh @`bc <<< 2^32-3708988800+1500000000`
2036 Feb 07 Thu 06:28:16+0000  JD 2464730.769630  MJD 64730.269630  ToD 23295
NTP 4294967296  Unix 2085978496  TAI-UTC 37 TAI-GPS 19 GPS-UTC 18
GPS We 2926  Cy 2 Wn 878  Wa 110 ToW 368914  DoW 4 ToD 23314

-- 
Take care. Thanks, Brian Inglis, Calgary, Alberta, Canada


More information about the questions mailing list