Date usage of Linux

Display time is a common command, and it is often used in writing shell scripts to display date-related file names or times. The date command is both Linux and Windows.

The use of the date command under Linux

• Date [OPTION] ... [+format]
• Date [-u|--utc|--universal] [MMDDHHMM[[CC]YY][.SS]]

Date command Arguments

• -d,–date=string displays the time specified by the STRING
• -f,–file=datefile similar –date parameter displays the time of each line in the Datefile file
• -ITIMESPEC,–ISO-8601[=TIMESPEC] Displays the date/time in ISO 8601 format. Timespec is one of "date" (dates only), "hours", "Minutes", "Senconds" (Display time precision), and defaults to "date".
• -r,–reference=file display the last modified time of the file
• -r,–rfc-2822 display time in RFC-2822 compatible date format
• -s,–set=string set Time to STRING
• -u,–utc,–universal display or set to Coordinated Universal Time format

Date command output display format

• Percent character%
• %a week abbreviation (Sun. Sat)
• %A full name of the week (Sunday). Saturday)
• %b abbreviation for month (Jan: DEC)
• Full name of the%B month (January). December)
• %c Date Time (Sat 12:02:33 EST 1989)
• %c century (year except 100 after finishing) [00-99]
• %d the day of the one month (01..31)
• %d Date (MM/DD/YY)
• %e Day of one months (1..31)
• %F date, same as%y-%m-%d
• %g year (YY)
• %G year (yyyy)
• %h with%b
• %H hours (00..23)
• %I Hours (01..12)
• %j the first day of the Year (001..366)
• %k hours (0..23)
• %l hours (1..12)
• %m Month (01..12)
• %M min (00..59)
• %n line break
• %N nanosecond (000000000..999999999)
• %p AM or PM
• %P am or PM
• %r 12-hour time (Hh:mm:ss [ap]m)
• %R 24-hour time (hh:mm)
• %s number of seconds starting from 00:00:00 1970-01-01 UTC
• %s seconds (00..60)
• %t tab
• %T 24-hour time (HH:MM:SS)
• The day of the week of%u (1..7); 1 = Monday
• %u week of the year, Sunday for the first day of the Week (00..53)
• %V Week of the year, Monday is the first day of the Week (01..53)
• %w Day of the Week (0..6); 0 on behalf of Sunday
• %W Week of the year, Monday is the first day of the Week (00..53)
• %x Date (MM/DD/YY)
• %x Time (%h:%m:%s)
• %y Year (00..99)
• %Y year (1970 ...)
• %Z RFC-2822 Style digital format time zone (-0500)
• %Z time zone (e.g., EDT), the time zone is not determined to be empty

A custom time example illustrates:

[Email protected] test]#DateThursday, October 12, 2017Geneva: +: ACst[[email protected] test]#Date-I .-Ten- A[email protected] test]#Date-ihours .-Ten-12t03+0800[email protected] test]#Date-iminutes .-Ten-12t03: A+0800[email protected] test]#Date-Iseconds .-Ten-12t03: A: A+0800[email protected] test]#Date-Rthu, AOct . Geneva: the: A+0800[email protected] test]#Date-u2017 Wednesday, October 11 +: the: +Utc[[email protected] test]#Date+"Today is%A."Today is Thursday. [Email protected] test]#Date+"date:%b.%e,%G"date:10 month. A, .[email protected] test]#Date+"Date:%b.%e,%G"date:10 month. A, .[email protected] test]#Date+"%x%x"October 12, 2017 03:42 56 seconds [[email protected] test]#Date+"%y-%m-%d%h:%m:%s" .-Ten- A Geneva: +: -[email protected] test]#Date+"%y-%m-%d%i:%m:%s%p" .-Ten- A Geneva: +: -morning [[email protected] test]#

Common time Formats:

Date " +%y-%m-%d%h:%m:%s " $-ten:$-date"  +%y-%m-%d " [email protected] test]# 

Linux date Plus and minus operations

[Email protected] test]#Date#正常时间2017年 Thursday, October 12Geneva: the: theCst[[email protected] test]#Date+"%b%e,%G"#自定义时间格式10月 A, .[email protected] test]#Date+"%b%e,%G"-D'-1 Day'#时间减1天, plus 1 days like October One, .[email protected] test]#Date+"%b%e,%G"-D'+1 Month'#时间加一个月, minus one months like November A, .[email protected] test]#Date+"%y year%m month%d day"#自定义时间格式, Date October 12, 2017 [email protected] test]#Date+"%y year%m month%d day"-D'-1 Day'#同上面加减1天 (or plus minus January) October 11, 2017 [[email protected] test]#Date+"%y year%-m month%d day"#去除月份前的0, for example ' August 12, 2017 ' displayed as ' August 12, 2017 ' October 12, 2017 [[email protected] test]#Date-D'-1 Day'+"%b%e,%G"#时间减1天, plus 1 days like October One, .[email protected] test]#Date-D'+1 Month'+"%b%e,%G"#时间加一个月, minus one months like November A, .[email protected] test]#

Date usage of Linux