ubuntu 指令修改时区 tzselect

修改时区

tzselect 指令只是根据提示一步步选择正确时区，但不能真正修改时区，最后输入提示的指令，然后重启，才能永久修改。

aaron@ubuntu:~$ tzselect
Please identify a location so that time zone rules can be set correctly.
Please select a continent, ocean, "coord", or "TZ".
 ) Africa
 ) Americas
 ) Antarctica
 ) Asia
 ) Atlantic Ocean
 ) Australia
 ) Europe
 ) Indian Ocean
 ) Pacific Ocean
) coord - I want to use geographical coordinates.
) TZ - I want to specify the time zone using the Posix TZ format.
#?
Please select a country whose clocks agree with yours.
 ) Afghanistan           ) Israel                ) Palestine
 ) Armenia               ) Japan                 ) Philippines
 ) Azerbaijan            ) Jordan                ) Qatar
 ) Bahrain               ) Kazakhstan            ) Russia
 ) Bangladesh            ) Korea (North)         ) Saudi Arabia
 ) Bhutan                ) Korea (South)         ) Singapore
 ) Brunei                ) Kuwait                ) Sri Lanka
 ) Cambodia              ) Kyrgyzstan            ) Syria
 ) China                 ) Laos                  ) Taiwan
) Cyprus                ) Lebanon               ) Tajikistan
) East Timor            ) Macau                 ) Thailand
) Georgia               ) Malaysia              ) Turkmenistan
) Hong Kong             ) Mongolia              ) United Arab Emirates
) India                 ) Myanmar (Burma)       ) Uzbekistan
) Indonesia             ) Nepal                 ) Vietnam
) Iran                  ) Oman                  ) Yemen
) Iraq                  ) Pakistan
#?
Please select one of the following time zone regions.
) Beijing Time
) Xinjiang Time
#? 

The following information has been given:

        China
        Beijing Time

Therefore TZ='Asia/Shanghai' will be used.
Local time is now:      Thu May  :: CST .
Universal Time is now:  Thu May  :: UTC .
Is the above information OK?
) Yes
) No
#? 

You can make this change permanent for yourself by appending the line
        TZ='Asia/Shanghai'; export TZ
to the file '.profile' in your home directory; then log out and log in again.

Here is that TZ value again, this time on standard output so that you
can use the /usr/bin/tzselect command in shell scripts:
Asia/Shanghai
// 此时时区还没有修改成功
// 根据提示输入 TZ='Asia/Shanghai'; export TZ 但重启后又失效
aaron@ubuntu:~$ date
Wed May  :: PDT
aaron@ubuntu:~$ sudo cp /usr/share/zoneinfo/Asia/Shanghai /etc/localtime
[sudo] password for aaron:
// 更新时间时，提示没有安装 ntpdate
aaron@ubuntu:~$ sudo ntpdate time.windows.com
sudo: ntpdate: command not found
// 安装
aaron@ubuntu:~$ sudo apt-get install ntpdate
// 更新时间
aaron@ubuntu:~$ sudo ntpdate time.windows.com
 May :: ntpdate[]: adjust time server 51.140.127.197 offset 0.044998 sec
aaron@ubuntu:~$ date
Thu May  :: CST
// 重启
aaron@ubuntu:~$ sudo reboot
// 时区设置成功
aaron@ubuntu:~$ date
Thu May  :: CST