时间管理

date 命令

date 命令用于输出当前时间

$ date
2016年 03月 14日 星期一 17:32:35 CST

date 命令后面用加号(+)指定显示的格式。

$ date +%d_%b_%Y
10_Sep_2018

$ date +%D
09/10/18

$ date +%F-%T
2018-09-10-11:09:51

完整的格式参数如下。

• %a 星期名的缩写(Sun)
• %A 星期名的全称(Sunday)
• %b 月份的缩写(Jan)
• %B 月份的全称(January)
• %c 日期和时间(Thu Mar 3 23:05:25 2005)
• %C 世纪，就是年份数省略后两位(20)
• %d 一个月的第几天(01)
• %D 日期，等同于%m/%d/%y
• %e 一个月的第几天，用空格补零，等同于%_d
• %F 完整的日期，等同于%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 等同于%b
• %H 小时(00..23)
• %I 小时(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 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 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)
• %😒 +hh:mm numeric timezone (e.g., -04:00)
• %:😒 +hh:mm:ss numeric time zone (e.g., -04:00:00)
• %Z alphabetic time zone abbreviation (e.g., EDT)

cal 命令

cal 命令用于显示日历。不带有参数时，显示的是当前月份。

$ cal
      三月 2016
日 一 二 三 四 五 六
       1  2  3  4  5
 6  7  8  9 10 11 12
13 14 15 16 17 18 19
20 21 22 23 24 25 26
27 28 29 30 31