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author | rgrimes <rgrimes@FreeBSD.org> | 1994-05-26 06:18:55 +0000 |
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committer | rgrimes <rgrimes@FreeBSD.org> | 1994-05-26 06:18:55 +0000 |
commit | e3cfc8ce61f788739c66445d903f8beacb40c93d (patch) | |
tree | ba7beef9ee9289c4383bad976f88710e44c98b4d /bin/date/date.1 | |
parent | 862fdf11a2ede45dec0da01ed575525d79468981 (diff) | |
download | FreeBSD-src-e3cfc8ce61f788739c66445d903f8beacb40c93d.zip FreeBSD-src-e3cfc8ce61f788739c66445d903f8beacb40c93d.tar.gz |
BSD 4.4 Lite bin Sources
Diffstat (limited to 'bin/date/date.1')
-rw-r--r-- | bin/date/date.1 | 230 |
1 files changed, 230 insertions, 0 deletions
diff --git a/bin/date/date.1 b/bin/date/date.1 new file mode 100644 index 0000000..0eb6c7b --- /dev/null +++ b/bin/date/date.1 @@ -0,0 +1,230 @@ +.\" Copyright (c) 1980, 1990, 1993 +.\" The Regents of the University of California. All rights reserved. +.\" +.\" This code is derived from software contributed to Berkeley by +.\" the Institute of Electrical and Electronics Engineers, Inc. +.\" +.\" Redistribution and use in source and binary forms, with or without +.\" modification, are permitted provided that the following conditions +.\" are met: +.\" 1. Redistributions of source code must retain the above copyright +.\" notice, this list of conditions and the following disclaimer. +.\" 2. Redistributions in binary form must reproduce the above copyright +.\" notice, this list of conditions and the following disclaimer in the +.\" documentation and/or other materials provided with the distribution. +.\" 3. All advertising materials mentioning features or use of this software +.\" must display the following acknowledgement: +.\" This product includes software developed by the University of +.\" California, Berkeley and its contributors. +.\" 4. Neither the name of the University nor the names of its contributors +.\" may be used to endorse or promote products derived from this software +.\" without specific prior written permission. +.\" +.\" THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND +.\" ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE +.\" IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE +.\" ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE +.\" FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL +.\" DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS +.\" OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) +.\" HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT +.\" LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY +.\" OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF +.\" SUCH DAMAGE. +.\" +.\" @(#)date.1 8.2 (Berkeley) 11/17/93 +.\" +.Dd November 17, 1993 +.Dt DATE 1 +.Os +.Sh NAME +.Nm date +.Nd display or set date and time +.Sh SYNOPSIS +.Nm date +.Op Fl d Ar dst +.Op Fl r Ar seconds +.Op Fl t Ar minutes_west +.Op Fl nu +.Op Cm + Ns Ar format +.Op [yy[mm[dd[hh]]]]mm[\&.ss] +.Sh DESCRIPTION +.Nm Date +displays the current date and time when invoked without arguments. +Providing arguments will format the date and time in a user-defined +way or set the date. +Only the superuser may set the date. +.Pp +The options are as follows: +.Bl -tag -width Ds +.It Fl d +Set the kernel's value for daylight savings time. +If +.Ar dst +is non-zero, future calls +to +.Xr gettimeofday 2 +will return a non-zero +.Ql tz_dsttime . +.It Fl n +The utility +.Xr timed 8 +is used to synchronize the clocks on groups of machines. +By default, if +.Xr timed +is running, +.Nm date +will set the time on all of the machines in the local group. +The +.Fl n +option stops +.Nm date +from setting the time for other than the current machine. +.It Fl r +Print out the date and time in +.Ar seconds +from the Epoch. +.It Fl t +Set the kernel's value for minutes west of +.Tn GMT . +.Ar Minutes_west +specifies the number of minutes returned in +.Ql tz_minuteswest +by future calls to +.Xr gettimeofday 2 . +.It Fl u +Display or set the date in +.Tn UCT +(universal) time. +.El +.Pp +An operand with a leading plus (``+'') sign signals a user-defined format +string which specifies the format in which to display the date and time. +The format string may contain any of the conversion specifications described +in the +.Xr strftime 3 +manual page, as well as any arbitrary text. +The format string for the default display is: +.Bd -literal -offset indent +``%a %b %e %H:%M:%S %Z n''. +.Ed +.Pp +If an operand does not have a leading plus sign, it is interpreted as +a value for setting the system's notion of the current date and time. +The canonical representation for setting the date and time is: +.Pp +.Bl -tag -width Ds -compact -offset indent +.It Ar yy +Year in abbreviated form (.e.g 89 for 1989). +.It Ar mm +Numeric month. +A number from 1 to 12. +.It Ar dd +Day, a number from 1 to 31. +.It Ar hh +Hour, a number from 0 to 23. +.It Ar mm +Minutes, a number from 0 to 59. +.It Ar .ss +Seconds, a number from 0 to 61 (59 plus a a maximum of two leap seconds). +.El +.Pp +Everything but the minutes is optional. +.Pp +Time changes for Daylight Saving and Standard time and leap seconds +and years are handled automatically. +.Sh EXAMPLES +The command: +.Bd -literal -offset indent +date ``+DATE: %m/%d/%y%nTIME: %H:%M:0n'' +.Ed +.Pp +will display: +.Bd -literal -offset indent +DATE: 11/21/87 +TIME: 13:36:16 +.Ed +.Pp +The command: +.Bd -literal -offset indent +date 8506131627 +.Ed +.Pp +sets the date to +.Dq Li "June 13, 1985, 4:27 PM" . +.Pp +The command: +.Bd -literal -offset indent +date 1432 +.Ed +.Pp +sets the time to +.Li "2:32 PM" , +without modifying the date. +.Sh ENVIRONMENTAL VARIABLES +The following environment variables affect the execution of +.Nm date : +.Bl -tag -width TZ +.It Ev TZ +The timezone to use when displaying dates. +See +.Xr environ 7 +for more information. +.El +.Sh FILES +.Bl -tag -width /var/log/messages -compact +.It Pa /var/log/wtmp +A record of date resets and time changes. +.It Pa /var/log/messages +A record of the user setting the time. +.El +.Sh SEE ALSO +.Xr gettimeofday 2 , +.Xr strftime 3 , +.Xr utmp 5 , +.Xr timed 8 +.Rs +.%T "TSP: The Time Synchronization Protocol for UNIX 4.3BSD" +.%A R. Gusella +.%A S. Zatti +.Re +.Sh DIAGNOSTICS +Exit status is 0 on success, 1 if unable to set the date, and 2 +if able to set the local date, but unable to set it globally. +.Pp +Occasionally, when +.Xr timed +synchronizes the time on many hosts, the setting of a new time value may +require more than a few seconds. +On these occasions, +.Nm date +prints: +.Ql Network time being set . +The message +.Ql Communication error with timed +occurs when the communication +between +.Nm date +and +.Xr timed +fails. +.Sh BUGS +The system attempts to keep the date in a format closely compatible +with +.Tn VMS . +.Tn VMS , +however, uses local time (rather than +.Tn GMT ) +and does not understand daylight-savings time. +Thus, if you use both +.Tn UNIX +and +.Tn VMS , +.Tn VMS +will be running on +.Tn GMT . +.Sh STANDARDS +The +.Nm date +command is expected to be compatible with +.St -p1003.2 . |