Linux 時間管理常用指令收集

• 1. date
• 2. ntpdate
• 3. hwclock

1. date

[說明]

查看或設定時間。

[範例]

查看時間

cy@cyvm:~$ date
公曆 20十七年 一月 卅日 週一 十六時47分廿四秒

查看時間，顯示成英文格式

cy@cyvm:~$ LANG=en_US ; date
Mon Jan 30 16:53:18 CST 2017

cy@cyvm:~$ LANG=en ; date
Mon Jan 30 16:53:31 CST 2017

查看時間，格式化顯示時間

cy@cyvm:~$ date +"%Y-%m-%d %H:%M:%S"
2017-01-30 17:05:53
cy@cyvm:~$ date +"%s"
1485767170

• 一般常用年月日時分秒組合數字格式
  

  %F	full date; same as %Y-%m-%d
  %T	time; same as %H:%M:%S
  %Y	year
  %m	month (01..12)
  %d	day of month (e.g., 01)
  %H	hour (00..23)
  %M	minute (00..59)
  %S	second (00..60)
  %N	nanoseconds (000000000..999999999)

  
  
• 月份文字
  

  %B	locale's full month name (e.g., January)
  %b	locale's abbreviated month name (e.g., Jan)
  %h	same as %b

  
  
• 星期文字
  

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

  
  
• 時區
  

  %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)

  
  
• UNIX Timestamp (Epoch time)
  

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

  
  
• 年或週的週期日數
  

  %j	day of year (001..366)
  %u	day of week (1..7); 1 is Monday

  
  
• 週數
  

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

  
  
• ISO week number
  

  %G	year of ISO week number (see %V); normally useful only with %V
  %g	last two digits of year of ISO week number (see %G)
  %V	ISO week number, with Monday as first day of week (01..53)

  
  
• 世紀
  

  %C	century; like %Y, except omit last two digits (e.g., 20)
  %y	last two digits of year (00..99)

  
  
• １２小時制
  

  %I	hour (01..12)
  %p	locale's equivalent of either AM or PM; blank if not known
  %P	like %p, but lower case

  
  
• 地區限定格式
  

  %c	locale's date and time (e.g., Thu Mar 3 23:05:25 2005)
  %x	locale's date representation (e.g., 12/31/99)
  %X	locale's time representation (e.g., 23:13:48)
  %r	locale's 12-hour clock time (e.g., 11:11:04 PM)

  
  
• 特殊文字
  

  %%	a literal %
  %n	a newline
  %t	a tab

  
  
• 不常用或有其他替代方案的格式
  

  %D	date; same as %m/%d/%y
  %R	24-hour hour and minute; same as %H:%M
  %e	day of month, space padded; same as %_d
  %k	hour, space padded ( 0..23); same as %_H
  %l	hour, space padded ( 1..12); same as %_I
  %w	day of week (0..6); 0 is Sunday

  
  

設定時間

＊注意！操作此需要 root 權限。

cy@cyvm:~$ sudo date +"%Y-%m-%d %H:%M:%S" -s "2016-10-05 12:24:36"
2016-10-05 12:24:36

---

2. ntpdate

[說明]

經由 NTP (Network Time Protocol，RFC 1305)，設定系統時間。

[範例]

設定時間

＊注意！操作此需要 root 權限。

cy@cyvm:~$ sudo ntpdate -s time.stdtime.gov.tw

---

3. hwclock

[說明]

在 Linux 下操作時間，一般都只是寫入作業系統，若要同步寫入硬體(RTC, real-time clock)，需要使用此指令。

[範例]

查看時間

cy@cyvm:~$ sudo hwclock -r
Mon Jan 30 05:35:39 2017  .262043 seconds

設定時間

cy@cyvm:~$ sudo hwclock -w