Linux 日期格式

系统管理员 2023-10-01 08:00 13阅读 0赞

这将是一个非常简单的指南，但我经常发现自己需要一个指南（*因为谁能记住这些格式，对吧？*）。

`date`默认情况下，Linux命令具有非常易读的输出。

$ date
    Wed Dec 30 21:50:15 CET 2015

If 还允许您使用特殊的 FORMAT 选项修改其输出。那些写成`date +"FORMAT"`. 下面的一些例子。

例如，一个简单的 YYYY-MM-DD 表示：

$ date +"%Y-%m-%d"
    2015-12-30

或者只是显示当前时间：

$ date +"%T"
    21:55:16

或者更完整的示例，它遵循显示日期的 Apache 日志格式（即：*\[30/Dec/2015:21:48:45 +0100\]*）。

$ date +"[%d/%b/%Y:%k:%M:%S %z]"
    [30/Dec/2015:12:58:32 +0100]

该`date`命令还允许您非常轻松地操作“当前日期”。默认情况下，`date`指的是“现在”。当您执行命令时，它将显示当前时间或日期。使用该`-d`参数，您还可以让它来回跳转并显示不同的日期。

$ date +"%Y-%m-%d"
    2015-12-30
    
    $ date +"%Y-%m-%d" -d "8 days ago"
    2015-12-22
    
    $ date +"%Y-%m-%d" -d "next Sunday"
    2016-01-03
    
    $ date +"%Y-%m-%d" -d "last Friday"
    2015-12-25

这是修饰符的完整列表。您可以在上面的任何示例中替换它们以获得不同的输出。

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 ( 0..23)
    %l     hour ( 1..12)
    %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 timezone (e.g., -0400)
    %:z    +hh:mm numeric timezone (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

这些修饰符在脚本中特别有用。您可以获得一个易于使用的日期变量来记录这样的文件。

$ cat script.sh
    #!/bin/bash
    TODAY=$(date +"%Y-%m-%d")
    
    echo $TODAY

如果你执行它：

$ ./script.sh
    2015-12-30

挺容易。