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DATE(1)                     UNIX Reference Manual                      DATE(1)

N\bNA\bAM\bME\bE
    d\bda\bat\bte\be - Display or set date and time

S\bSY\bYN\bNO\bOP\bPS\bSI\bIS\bS
    d\bda\bat\bte\be [-\b-n\bnu\bu] [-\b-d\bd _\bd_\bs_\bt] [-\b-t\bt _\bm_\bi_\bn_\bu_\bt_\be_\bs__\bw_\be_\bs_\bt] [yymmddhhmm [.ss]]

D\bDE\bES\bSC\bCR\bRI\bIP\bPT\bTI\bIO\bON\bN
    D\bDa\bat\bte\be displays today's date and time when invoked without arguments.  Pro-
    viding an argument will set the desired date; only the superuser can set
    the date.

    Options are:

    -\b-d\bd    Set the kernel's values for daylight savings time.  If _\bd_\bs_\bt is non-
          zero, future calls to gettimeofday(2) will return a non-zero
          `tz_dsttime'.

    -\b-t\bt    Set the kernel's values for minutes west of GMT.  _\bM_\bi_\bn_\bu_\bt_\be_\bs__\bw_\be_\bs_\bt pro-
          vides the number of minutes returned by future calls to gettimeof-
          day(2) in `tz_minuteswest'.

    -\b-u\bu    Display or set the date in GMT (universal) time.

    The canonical representation for setting the date and time:

          _\by_\by        Year in abbreviated form (.e.g 89 for 1989).
          _\bm_\bm        Numeric month.  A number from 01 to 12.
          _\bd_\bd        Day, a number from 01 to 31.
          _\bh_\bh        Hour, a number from 00 to 24.
          _\bm_\bm        Minutes, a number from 00 to 60.
          ._\bs_\bs       Seconds, a number from 00 to 60.

    The command:

          date 8506131627

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

    To reset today's time, the incantation can be shortened to just the hours
    and minutes:

          date 1432

    sets the time to 2:32 PM, unaffecting the date.

    Providing a system stays running, date will handle time changes for
    daylight/standards savings time and leap times.

    If timed(8) is running to synchronize the clocks of machines in a local
    area network, d\bda\bat\bte\be sets the time globally on all those machines unless
    the -\b-n\bn option is given.

F\bFI\bIL\bLE\bES\bS
    /_\bv_\ba_\br/_\bl_\bo_\bg/_\bw_\bt_\bm_\bp   A record of date resets and time changes.
    /_\bv_\ba_\br/_\bl_\bo_\bg/_\bm_\be_\bs_\bs_\ba_\bg_\be_\bs       A record of the name of the user setting the time.

S\bSE\bEE\bE A\bAL\bLS\bSO\bO
    gettimeofday(2), utmp(5), timed(8)
    _\bT_\bS_\bP: _\bT_\bh_\be _\bT_\bi_\bm_\be _\bS_\by_\bn_\bc_\bh_\br_\bo_\bn_\bi_\bz_\ba_\bt_\bi_\bo_\bn _\bP_\br_\bo_\bt_\bo_\bc_\bo_\bl _\bf_\bo_\br _\bU_\bN_\bI_\bX _\b4._\b3_\bB_\bS_\bD, R. Gusella
    and S. Zatti

H\bHI\bIS\bST\bTO\bOR\bRY\bY
    D\bDa\bat\bte\be appeared in Version 6 AT&T UNIX.

D\bDI\bIA\bAG\bGN\bNO\bOS\bST\bTI\bIC\bCS\bS
    Exit status is 0 on success, 1 on complete failure to set the date, and 2
    on successfully setting the local date but failing 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, d\bda\bat\bte\be prints: `Network time being set'.  The message `Communication
    error with timed' occurs when the communication between d\bda\bat\bte\be and timed
    fails.

B\bBU\bUG\bGS\bS
    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-saving time.  Thus, if you use both UNIX and VMS, VMS will
    be running on GMT.