Timezone

Abstract

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• A standard to the current date and time at different parts of the world

Read current data and time in python

import datetime
print(datetime.datetime.now().strftime("%A, %B %d, %Y at %I:%M %p"))

Read current data and time in POSIX

date

• The current system timezone info is stored inside /etc/localtime

Change Timezone

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Timezone Code

Refer to this List of timezone codes.

System-level

• sudo timedatectl set-timezone <TIMEZONE_CODE> on POSIX

Process-level

• Install tzdata(a time zone database) into the system with a Package Manager and set the timezone with export TZ=<TIMEZONE_CODE>
• Docker Container is a Process (进程), so setting timezone in this matter is similar to setting a system-level timezone for the application running inside the container

Application-level

• Set it with the corresponding SDK of the language used to code the app

System-level vs Process-level

As you can see changing timezone on a process level doesn’t affect the system-level timezone. And all processes follow the system-level timezone by default.