DATE(1) BSD Reference Manual DATE(1)
date - display or set date and time
date [-d dst] [-r seconds] [-t minutes_west] [-nu] [+format]
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.
The options are as follows:
-d Set the kernel's value for daylight savings time. If dst is non-
zero, future calls to gettimeofday(2) will return a non-zero
-n The utility timed(8) is used to synchronize the clocks on groups
of machines. By default, if timed is running, date will set the
time on all of the machines in the local group. The -n option
stops date from setting the time for other than the current ma-
-r Print out the date and time in seconds from the Epoch.
-t Set the kernel's value for minutes west of GMT. Minutes_west
specifies the number of minutes returned in `tz_minuteswest' by
future calls to gettimeofday(2).
-u Display or set the date in UCT (universal) time.
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 de-
scribed in the strftime(3) manual page, as well as any arbitrary text. A
<newline> character is always output after the characters specified by
the format string. The format string for the default display is:
``%a %b %e %H:%M:%S %Z %Y''.
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:
yy Year in abbreviated form (.e.g 89 for 1989).
mm Numeric month. A number from 1 to 12.
dd Day, a number from 1 to 31.
hh Hour, a number from 0 to 23.
mm Minutes, a number from 0 to 59.
.ss Seconds, a number from 0 to 61 (59 plus a a maximum of two
Everything but the minutes is optional.
Time changes for Daylight Saving and Standard time and leap seconds and
years are handled automatically.
date ``+DATE: %m/%d/%y%nTIME: %H:%M:%S''
sets the date to ``June 13, 1985, 4:27 PM''.
sets the time to 2:32 PM, without modifying the date.
The following environment variables affect the execution of date:
The timezone to use when displaying dates. See environ(7) for more in-
/var/log/wtmp A record of date resets and time changes.
/var/log/messages A record of the user setting the time.
gettimeofday(2), strftime(3), utmp(5), timed(8)
R. Gusella, and S. Zatti, TSP: The Time Synchronization Protocol for UNIX
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.
Occasionally, when timed synchronizes the time on many hosts, the setting
of a new time value may require more than a few seconds. On these occa-
sions, date prints: `Network time being set'. The message `Communication
error with timed' occurs when the communication between date and timed
The system attempts to keep the date in a format closely compatible with
VMS. VMS, however, uses local time (rather than GMT) and does not under-
stand daylight-savings time. Thus, if you use both UNIX and VMS, VMS
will be running on GMT.
The date command is expected to be compatible with IEEE Std1003.2
4.4BSD April 28, 1995 2