1.\" Copyright (c) 1980, 1990 The Regents of the University of California. 2.\" All rights reserved. 3.\" 4.\" %sccs.include.redist.man% 5.\" 6.\" @(#)date.1 6.8 (Berkeley) 07/24/90 7.\" 8.Dd 9.Dt DATE 1 10.Os BSD 4.4 11.Sh NAME 12.Nm date 13.Nd display or set date and time 14.Sh SYNOPSIS 15.Nm date 16.Op Fl nu 17.Op Fl d Ar dst 18.Op Fl t Ar minutes_west 19.Op yymmddhhmm [\&.ss] 20.Sh DESCRIPTION 21.Nm Date 22displays today's date and time when invoked without 23arguments. Providing an argument will set the desired date; 24only the superuser can set the date. 25.Pp 26Options are: 27.Pp 28.Tw Ds 29.Tp Fl d 30Set the kernel's values for daylight savings time. 31If 32.Ar dst 33is non-zero, future calls 34to 35.Xr gettimeofday 2 36will return a non-zero 37.Ql tz_dsttime . 38.Tp Fl t 39Set the kernel's values for minutes west of GMT. 40.Ar Minutes_west 41provides the number of minutes returned by future calls to 42.Xr gettimeofday 2 43in 44.Ql tz_minuteswest . 45.Tp Fl u 46Display or set the date in GMT (universal) time. 47.Tp 48.Pp 49The canonical representation for setting the date and time: 50.Dw Ds 51.Dp Ar yy 52Year in abbreviated form (.e.g 89 for 1989). 53.Dp Ar mm 54Numeric month. 55A number from 01 to 12. 56.Dp Ar dd 57Day, a number from 01 to 31. 58.Dp Ar hh 59Hour, a number from 00 to 24. 60.Dp Ar mm 61Minutes, a number from 00 to 60. 62.Dp Ar .ss 63Seconds, a number from 00 to 60. 64.Dp 65The command: 66.Pp 67.Dl date 8506131627 68.Pp 69sets the date to June 13 1985, 4:27 PM. 70.Pp 71To reset today's time, the incantation can be shortened 72to just the hours and minutes: 73.Pp 74.Dl date 1432 75.Pp 76sets the time to 2:32 PM, unaffecting the date. 77.Pp 78Providing a system stays running, date will handle 79time changes for daylight/standards savings time and leap times. 80.Pp 81If 82.Xr timed 8 83is running to synchronize the clocks of machines in a local 84area network, 85.Nm date 86sets the time globally on all those 87machines unless the 88.Fl n 89option is given. 90.Sh FILES 91.Dw /var/log/messages 92.Di L 93.Dp Pa /var/log/wtmp 94A record of date resets and time changes. 95.Dp Pa /var/log/messages 96A record of the name of the user 97setting the time. 98.Sh SEE ALSO 99.Xr gettimeofday 2 , 100.Xr utmp 5 , 101.Xr timed 8 102.br 103.Em TSP:\ The\ Time\ Synchronization Protocol 104.Em for UNIX 4.3BSD , 105R. Gusella 106and\ S.\ Zatti 107.Sh HISTORY 108.Nm Date 109appeared in Version 6 AT&T UNIX. 110.Sh DIAGNOSTICS 111Exit status is 0 on success, 1 on complete failure to set the date, 112and 2 on successfully setting the local date but failing globally. 113.Pp 114Occasionally, when 115.Xr timed 116synchronizes the time on many hosts, 117the setting of a new time value may require more than a few seconds. 118On these occasions, 119.Nm date 120prints: `Network time being set'. 121The message `Communication error with timed' occurs when the communication 122between 123.Nm date 124and 125.Xr timed 126fails. 127.Sh BUGS 128The system attempts to keep the date in a format closely compatible 129with VMS. VMS, however, uses local time (rather than GMT) and does 130not understand daylight-saving time. Thus, if you use both UNIX 131and VMS, VMS will be running on GMT. 132