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[bozhu@bozhuNo1 ~]$ man date

DATE(1)                                         User Commands                                         DATE(1)

NAME
       date - print or set the system date and time

SYNOPSIS
       date [OPTION]... [+FORMAT]
       date [-u|--utc|--universal] [MMDDhhmm[[CC]YY][.ss]]

DESCRIPTION
       Display the current time in the given FORMAT, or set the system date.

       Mandatory arguments to long options are mandatory for short options too.

       -d, --date=STRING
              display time described by STRING, not 'now'

       -f, --file=DATEFILE
              like --date once for each line of DATEFILE

       -I[TIMESPEC], --iso-8601[=TIMESPEC]
              output  date/time  in  ISO  8601 format.  TIMESPEC='date' for date only (the default), 'hours',
              'minutes', 'seconds', or 'ns' for date and time to the indicated precision.

       -r, --reference=FILE
              display the last modification time of FILE

       -R, --rfc-2822
              output date and time in RFC 2822 format.  Example: Mon, 07 Aug 2006 12:34:56 -0600

       --rfc-3339=TIMESPEC
              output date and time in RFC 3339 format.  TIMESPEC='date', 'seconds', or 'ns' for date and time
              to  the  indicated  precision.   Date  and  time  components  are  separated by a single space:
              2006-08-07 12:34:56-06:00

       -s, --set=STRING
              set time described by STRING

       -u, --utc, --universal
              print or set Coordinated Universal Time (UTC)

       --help display this help and exit

       --version
              output version information and exit

       FORMAT controls the output.  Interpreted sequences are:

       %%     a literal %

       %a     locale's abbreviated weekday name (e.g., Sun)

       %A     locale's full weekday name (e.g., Sunday)

       %b     locale's abbreviated month name (e.g., Jan)

       %B     locale's full month name (e.g., January)

       %c     locale's date and time (e.g., Thu Mar  3 23:05:25 2005)

       %C     century; like %Y, except omit last two digits (e.g., 20)

       %d     day of month (e.g., 01)

       %D     date; same as %m/%d/%y

       %e     day of month, space padded; same as %_d

       %F     full date; same as %Y-%m-%d

       %g     last two digits of year of ISO week number (see %G)

       %G     year of ISO week number (see %V); normally useful only with %V

       %h     same as %b

       %H     hour (00..23)

       %I     hour (01..12)

       %j     day of year (001..366)

       %k     hour, space padded ( 0..23); same as %_H

       %l     hour, space padded ( 1..12); same as %_I

       %m     month (01..12)

       %M     minute (00..59)

       %n     a newline

       %N     nanoseconds (000000000..999999999)

       %p     locale's equivalent of either AM or PM; blank if not known

       %P     like %p, but lower case

       %r     locale's 12-hour clock time (e.g., 11:11:04 PM)

       %R     24-hour hour and minute; same as %H:%M

       %s     seconds since 1970-01-01 00:00:00 UTC

       %S     second (00..60)

       %t     a tab

       %T     time; same as %H:%M:%S

       %u     day of week (1..7); 1 is Monday

       %U     week number of year, with Sunday as first day of week (00..53)

       %V     ISO week number, with Monday as first day of week (01..53)

       %w     day of week (0..6); 0 is Sunday

       %W     week number of year, with Monday as first day of week (00..53)

       %x     locale's date representation (e.g., 12/31/99)

       %X     locale's time representation (e.g., 23:13:48)

       %y     last two digits of year (00..99)

       %Y     year

       %z     +hhmm numeric time zone (e.g., -0400)

       %:z    +hh:mm numeric time zone (e.g., -04:00)

       %::z   +hh:mm:ss numeric time zone (e.g., -04:00:00)

       %:::z  numeric time zone with : to necessary precision (e.g., -04, +05:30)

       %Z     alphabetic time zone abbreviation (e.g., EDT)

       By default, date pads numeric fields with zeroes.  The following optional flags may follow '%':

       -      (hyphen) do not pad the field

       _      (underscore) pad with spaces

       0      (zero) pad with zeros

       ^      use upper case if possible

       #      use opposite case if possible

       After any flags comes an optional field width, as a decimal number; then an optional  modifier,  which
       is  either  E  to  use  the  locale's alternate representations if available, or O to use the locale's
       alternate numeric symbols if available.

ENVIRONMENT
       TZ     Specifies the timezone, unless overridden by command line parameters.  If neither is specified,
              the setting from /etc/localtime is used.

EXAMPLES
       Convert seconds since the epoch (1970-01-01 UTC) to a date

              $ date --date='@2147483647'

       Show the time on the west coast of the US (use tzselect(1) to find TZ)

              $ TZ='America/Los_Angeles' date

       Show the local time for 9AM next Friday on the west coast of the US

       %H     hour (00..23)

       %I     hour (01..12)

       %j     day of year (001..366)

       %k     hour, space padded ( 0..23); same as %_H

       %l     hour, space padded ( 1..12); same as %_I

       %m     month (01..12)

       %M     minute (00..59)

       %n     a newline

       %N     nanoseconds (000000000..999999999)

       %p     locale's equivalent of either AM or PM; blank if not known

       %P     like %p, but lower case

       %r     locale's 12-hour clock time (e.g., 11:11:04 PM)

       %R     24-hour hour and minute; same as %H:%M

       %s     seconds since 1970-01-01 00:00:00 UTC

       %S     second (00..60)

       %t     a tab

       %T     time; same as %H:%M:%S

       %u     day of week (1..7); 1 is Monday

       %U     week number of year, with Sunday as first day of week (00..53)

       %V     ISO week number, with Monday as first day of week (01..53)

       %w     day of week (0..6); 0 is Sunday

       %W     week number of year, with Monday as first day of week (00..53)

       %x     locale's date representation (e.g., 12/31/99)

       %X     locale's time representation (e.g., 23:13:48)

       %y     last two digits of year (00..99)

       %Y     year

       %z     +hhmm numeric time zone (e.g., -0400)

       %:z    +hh:mm numeric time zone (e.g., -04:00)

       %::z   +hh:mm:ss numeric time zone (e.g., -04:00:00)

       %:::z  numeric time zone with : to necessary precision (e.g., -04, +05:30)

       %Z     alphabetic time zone abbreviation (e.g., EDT)

       By default, date pads numeric fields with zeroes.  The following optional flags may follow '%':

       -      (hyphen) do not pad the field

       _      (underscore) pad with spaces

       0      (zero) pad with zeros

       ^      use upper case if possible

       #      use opposite case if possible

       After any flags comes an optional field width, as a decimal number; then an optional  modifier,  which
       is  either  E  to  use  the  locale's alternate representations if available, or O to use the locale's
       alternate numeric symbols if available.

ENVIRONMENT
       TZ     Specifies the timezone, unless overridden by command line parameters.  If neither is specified,
              the setting from /etc/localtime is used.

EXAMPLES
       Convert seconds since the epoch (1970-01-01 UTC) to a date

              $ date --date='@2147483647'

       Show the time on the west coast of the US (use tzselect(1) to find TZ)

              $ TZ='America/Los_Angeles' date

       Show the local time for 9AM next Friday on the west coast of the US

              $ date --date='TZ="America/Los_Angeles" 09:00 next Fri'

       GNU  coreutils  online  help: <http://www.gnu.org/software/coreutils/> Report date translation bugs to
       <http://translationproject.org/team/>

DATE STRING
       The --date=STRING is a mostly free format human readable  date  string  such  as  "Sun,  29  Feb  2004
       16:21:42  -0800"  or  "2004-02-29  16:21:42" or even "next Thursday".  A date string may contain items
       indicating calendar date, time of day, time zone, day of week, relative time, relative date, and  num‐
       bers.   An  empty  string  indicates the beginning of the day.  The date string format is more complex
       than is easily documented here but is fully described in the info documentation.

AUTHOR
       Written by David MacKenzie.

COPYRIGHT
       Copyright © 2013 Free  Software  Foundation,  Inc.   License  GPLv3+:  GNU  GPL  version  3  or  later
       <http://gnu.org/licenses/gpl.html>.
       This  is  free  software:  you  are  free to change and redistribute it.  There is NO WARRANTY, to the
       extent permitted by law.

SEE ALSO
       The full documentation for date is maintained as a Texinfo manual.  If the info and date programs  are
       properly installed at your site, the command

              info coreutils 'date invocation'

       should give you access to the complete manual.

GNU coreutils 8.22                              November 2015                                         DATE(1)

Info page

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