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date
summary
����This subchapter looks at date, a UNIX (and Linux) command.
����date is used to set or view the system date and time.
date
����This subchapter looks at date, a UNIX (and Linux) command.
����date is used to set or view the system date and time.
����$ date
����Mon Sep��3 00:56:17 PDT 2012
����$
����The format for the output is: day of the week, month, day of the month, 24 hour time, time zone, year.
formatted output
����Display the time and/or date with formatting by including formatting options (which can be used to set variables to a specific format).
����$ date '+DATE: %m/%d/%y%nTIME: %H:%M:%S'
����DATE: 11/23/13
����TIME: 22:12:19
����$
����Setting a variable with the current date:
����$ NOW=$(date +"%m/%d/%Y")
����$ echo $NOW
����11/23/2013
����$
Format specifiers (format string starts with +)
Specifier |
Description |
Values or example |
Day |
%a |
weekday, abbreviated |
Sun |
%A |
weekday, full |
Sunday |
%d |
day of the month, two digits, zero filled |
08 |
%e |
day of the month |
8 |
%j |
day of year, zero filled |
001�366 |
%u |
day of week from Monday to Sunday |
1�7 |
%w |
day of week from Sunday to Saturday |
0�6 |
Week |
%U |
week number, Sunday as first day of week |
00�53 |
%W |
week number, Monday as first day of week |
00�53 |
%V |
ISO standard week of the year |
01�53 |
Month |
%m |
two-digit month number |
01�12 |
%h |
month name, abbreviated |
Nov |
%b |
month name, localised abbreviation |
Nov |
%B |
locale's full month, variable length |
November |
Year |
%y |
two-digit year |
00�99 |
%Y |
four-digit year |
2013 |
%g |
two-digit year corresponding to the�%V week number |
|
%G |
four-digit year corresponding to the�%V week number |
|
Century |
%C |
two century digits from year |
00�99 |
Date |
%D |
mm/dd/yy |
11/24/13 |
%x |
locale's date representation |
11/24/2013 |
%F |
%Y-%m-%d |
2013-11-24 |
Hours |
%l |
hour (12 hour) |
4 |
%I |
hour (12 hour), zero-filled |
04 |
%k |
hour (24 hour) |
4 |
%H |
hour (24 hour), zero-padded |
04 |
%p |
locale's upper case AM or PM (blank in many locales) |
AM |
%P |
locale's lower case am or pm |
am |
Minutes |
%M |
two-digit minute number |
05 |
Seconds |
%s |
seconds since 00:00:00 1970-01-01 UTC (Unix epoch) |
1385265929 |
%S |
two-digit second number |
00�60 (Includes 60 to accommodate a leap second) |
%N |
nanoseconds |
000000000�999999999 |
Time |
%r |
hours, minutes, seconds (12-hour clock) |
04:05:29 AM |
%R |
hours, minutes (24 hour clock) |
04:05 |
%T |
hours, minutes, seconds (24-hour clock) |
04:05:29 |
%X |
locale's time representation |
11:07:26 AM |
Date and time |
%c |
locale's date and time |
Sat Nov 04 12:02:33 EST 1989 |
Time zone |
%z |
RFC-822 style numeric time zone |
-0500 |
%Z |
time zone name; nothing if no time zone is determinable |
EST, EDT |
literals: ���� %n newline ���� %% percent ���� %t horizontal tab
����By default, date normally fills numeric fields with zeroes. GNU date, but not BSD date, recognizes a modifier between the per cent sign (%) and the format specifier:
- hyphen (-): do not fill the field
- underscore (_): pad the field with spaces
����TZ Specifies the time zone, unless overridden by command line parameters. If neither is specified, the setting from /etc/localtime is used.
setting time and date
����Only the root or superuser an set the system date and time. In Mac OS X, you can use the clock system preferences t set the time and date. In Ubuntu-based Linux, you can click on the clock and select Time and Date settings from the menu or click on the System menu, select Adminsitration, select Time and Date.
����Set the time to noon:
����$ date 1200
����$
����Set the time to 3:30:30 a.m.:
����$ date 0330.30
����$
����Set the date to October 31st (Halloween) at 3:30 a.m.:
����$ date 10310330
����$
other
����On November 8, 2010, Ramesh Natarajan named this the number 49 most frequently used UNIX/Linux command at this web page 50 Most Frequently Used UNIX / Linux Commands (With Examples).
comments, suggestions, corrections, criticisms
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