SYSTEMD.TIME(7) systemd.time SYSTEMD.TIME(7) systemd.time - systemd . . systemd . : 2h 30min . 150 . . systemd . . : o usec, us, s o msec, ms o seconds, second, sec, s o minutes, minute, min, m o hours, hour, hr, h o days, day, d o weeks, week, w o months, month, M ( 30.44 ) o years, year, y ( 365.25 ) . "ns" "nsec" . . : 2 h 2hours 48hr 1y 12month 55s500ms 300ms20s 5day timespan systemd-analyze(1) . systemd ( ). ( ) D-Bus ( ) ( show systemctl(1)). "...Sec" "...USec" . . systemd : Fri 2012-11-23 23:02:15 CET . . UTC "UTC" . . . systemd "T" ( RFC 3339[1] ISO 8601) (CET) : "Fri 2012-11-23 23:02:15 CET" "Fri 2012-11-23T23:02:15" "2012-11-23T23:02:15 CET" "2012-11-23 23:02:15". . : "UTC" IANA ( .. "CET" "Asia/Tokyo" timedatectl list-timezones ( timedatectl(1))) "+-05" "+-0530" "+-05:30" "Z". RFC 3339[1] ISO 8601: " (+-05:30" "Z". : "2012-11-23T23:02:15+01:00" "2012-11-23 22:02:15Z". ("Wed") ("Wednesday") ( ) . . . 00:00:00. 1u0628] . 0. : "now" ( ). "today" "yesterday" "tomorrow" 00:00:00 . : ( ) "+" . "-" . "+" "-" "left" "ago". "@" 1970 00:00:00 . ( 2012-11-23 18:15:22 UTC+8 "TZ=:Asia/Shanghai"): Fri 2012-11-23 11:12:13 -> Fri 2012-11-23 11:12:13 2012-11-23 11:12:13 -> Fri 2012-11-23 11:12:13 2012-11-23 11:12:13 UTC -> Fri 2012-11-23 19:12:13 2012-11-23T11:12:13Z -> Fri 2012-11-23 19:12:13 2012-11-23T11:12+02:00 -> Fri 2012-11-23 17:12:00 2012-11-23 -> Fri 2012-11-23 00:00:00 12-11-23 -> Fri 2012-11-23 00:00:00 11:12:13 -> Fri 2012-11-23 11:12:13 11:12 -> Fri 2012-11-23 11:12:00 now -> Fri 2012-11-23 18:15:22 today -> Fri 2012-11-23 00:00:00 today UTC -> Fri 2012-11-23 16:00:00 yesterday -> Fri 2012-11-22 00:00:00 tomorrow -> Fri 2012-11-24 00:00:00 tomorrow Pacific/Auckland -> Thu 2012-11-23 19:00:00 +3h30min -> Fri 2012-11-23 21:45:22 -5s -> Fri 2012-11-23 18:15:17 11min ago -> Fri 2012-11-23 18:04:22 @1395716396 -> Tue 2014-03-25 03:59:56 ( "UTC"). . . : 2014-03-25 03:59:56.654563 systemd ( ) . : 2 months 5 days ago ( ). timestamp systemd-analyze(1) . . : Thu,Fri 2012-*-1,5 11:12:13 11:12:13 2012 . . (Wed) (Wednesday) ( ) . ".." . "" ".." . "*" . . "/" . ".." "/" . "~" . "*-02~03" " " "Mon *-05~07/1" " ". . 6 . 00:00:00 *-*-* . ":00". "UTC" ( ) IANA ( ). : minutely -> *-*-* *:*:00 hourly -> *-*-* *:00:00 daily -> *-*-* 00:00:00 monthly -> *-*-01 00:00:00 weekly -> Mon *-*-* 00:00:00 yearly -> *-01-01 00:00:00 quarterly -> *-01,04,07,10-01 00:00:00 semiannually -> *-01,07-01 00:00:00 : Sat,Thu,Mon..Wed,Sat..Sun -> Mon..Thu,Sat,Sun *-*-* 00:00:00 Mon,Sun 12-*-* 2,1:23 -> Mon,Sun 2012-*-* 01,02:23:00 Wed *-1 -> Wed *-*-01 00:00:00 Wed..Wed,Wed *-1 -> Wed *-*-01 00:00:00 Wed, 17:48 -> Wed *-*-* 17:48:00 Wed..Sat,Tue 12-10-15 1:2:3 -> Tue..Sat 2012-10-15 01:02:03 *-*-7 0:0:0 -> *-*-07 00:00:00 10-15 -> *-10-15 00:00:00 monday *-12-* 17:00 -> Mon *-12-* 17:00:00 Mon,Fri *-*-3,1,2 *:30:45 -> Mon,Fri *-*-01,02,03 *:30:45 12,14,13,12:20,10,30 -> *-*-* 12,13,14:10,20,30:00 12..14:10,20,30 -> *-*-* 12..14:10,20,30:00 mon,fri *-1/2-1,3 *:30:45 -> Mon,Fri *-01/2-01,03 *:30:45 03-05 08:05:40 -> *-03-05 08:05:40 08:05:40 -> *-*-* 08:05:40 05:40 -> *-*-* 05:40:00 Sat,Sun 12-05 08:05:40 -> Sat,Sun *-12-05 08:05:40 Sat,Sun 08:05:40 -> Sat,Sun *-*-* 08:05:40 2003-03-05 05:40 -> 2003-03-05 05:40:00 05:40:23.4200004/3.1700005 -> *-*-* 05:40:23.420000/3.170001 2003-02..04-05 -> 2003-02..04-05 00:00:00 2003-03-05 05:40 UTC -> 2003-03-05 05:40:00 UTC 2003-03-05 -> 2003-03-05 00:00:00 03-05 -> *-03-05 00:00:00 hourly -> *-*-* *:00:00 daily -> *-*-* 00:00:00 daily UTC -> *-*-* 00:00:00 UTC monthly -> *-*-01 00:00:00 weekly -> Mon *-*-* 00:00:00 weekly Pacific/Auckland -> Mon *-*-* 00:00:00 Pacific/Auckland yearly -> *-01-01 00:00:00 annually -> *-01-01 00:00:00 *:2/3 -> *-*-* *:02/3:00 systemd.timer(5) . calendar systemd-analyze(1) . . systemd(1), journalctl(1), systemd.timer(5), systemd.unit(5), systemd.directives(7), systemd-analyze(1) 1. RFC 3339 https://tools.ietf.org/html/rfc3339 3 . . : . systemd 260.2 SYSTEMD.TIME(7)