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DATE(1)                 NetBSD General Commands Manual                 DATE(1)


NAME

     date -- display or set date and time


SYNOPSIS

     date [-ajnu] [-d date] [-r seconds] [+format]
          [[[[[[CC]yy]mm]dd]HH]MM[.SS]]


DESCRIPTION

     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:

     -a      Use adjtime(2) to change the local system time slowly, maintain-
             ing it as a monotonically increasing function.  -a implies -n.

     -d date
             Parse the provided human-described date and time and display the
             result without actually changing the system clock.  (See
             parsedate(3) for examples.)

     -j      Parse the provided canonical representation of date and time
             (described below) and display the result without actually chang-
             ing the system clock.

     -n      The utility timed(8) is used to synchronize the clocks on groups
             of machines.  By default, if timed(8) 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 cur-
             rent machine.

     -r seconds
             Print out the date and time that is seconds from the Epoch.

     -u      Display or set the date in UTC (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
     described 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:

           CC      The first two digits of the year (the century).
           yy      The second two digits of the year.  If yy is specified, but
                   CC is not, a value for yy between 69 and 99 results in a CC
                   value of 19.  Otherwise, a CC value of 20 is used.
           mm      The month of the year, from 01 to 12.
           dd      The day of the month, from 01 to 31.
           HH      The hour of the day, from 00 to 23.
           MM      The minute of the hour, from 00 to 59.
           SS      The second of the minute, from 00 to 60.

     Everything but the minutes is optional.

     Time changes for Daylight Saving and Standard Time and leap seconds and
     years are handled automatically.


ENVIRONMENT

     The following environment variables affect the execution of date:

     TZ   The timezone to use when displaying dates.  See environ(7) for more
          information.


FILES

     /etc/localtime     Symlink pointing to system's default timezone informa-
                        tion file in /usr/share/zoneinfo directory.
     /var/log/wtmp      A record of date resets and time changes.
     /var/log/messages  A record of the user setting the time.


EXAMPLES

     The command:

           date '+DATE: %m/%d/%y%nTIME: %H:%M:%S'

     will display:

           DATE: 11/21/87
           TIME: 13:36:16

     The command:

           date 8506131627

     sets the date to ``June 13, 1985, 4:27 PM''.

     The command:

           date 1432

     sets the time to 2:32 PM, without modifying the date.


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.

     Occasionally, when timed(8) synchronizes the time on many hosts, the set-
     ting of a new time value may require more than a few seconds.  On these
     occasions, date prints: `Network time being set'.  The message
     `Communication error with' timed(8) occurs when the communication between
     date and timed(8) fails.


SEE ALSO

     adjtime(2), gettimeofday(2), settimeofday(2), parsedate(3), strftime(3),
     utmp(5), environ(7), timed(8)

     R. Gusella and S. Zatti, TSP: The Time Synchronization Protocol for UNIX
     4.3BSD.


STANDARDS

     The date utility is expected to be compatible with IEEE Std 1003.2
     (``POSIX.2'').


HISTORY

     A date utility appeared in Version 1 AT&T UNIX.

NetBSD 8.1                      August 11, 2016                     NetBSD 8.1