Master the Linux ‘export’ Command: A Comprehensive Guide

This article provides a comprehensive tutorial for beginners on the export command in Linux. It covers the command's history, when and why to use it, how to apply it, and some tricks and techniques. Additionally, it touches on common use cases and important points to consider when using the export command. By reading this article, you will gain a solid understanding of the export command and its role in setting and modifying environment variables in Linux systems.

Instructions

This article provides a detailed introduction to the Linux export command, covering its history, usage, and best practices for managing environment variables.

History

The export command has been a part of Unix-like operating systems since the early days of Unix. It was designed to help users manage environment variables, which are used to store and pass settings between processes and applications.

When and why to use it

The export command is used to set, modify, or remove environment variables. These variables are essential for configuring the behavior of various applications and processes in Linux, as they can store important data like file paths, configurations, and user preferences.

How to use it

To use the export command, simply type export followed by the variable name and its value:

export VARNAME=value

The commonly used parameters

The export command does not have specific parameters, but you can use it with different options when setting or modifying environment variables:

• -n Unset an environment variable

export -n VARNAME

• -p Display a list of exported environment variables

export -p

Other supported parameters

There are no additional parameters for the export command, as it primarily deals with environment variables.

Most common use cases

1. Set an environment variable

export PATH=$PATH:/new/directory

1. Remove an environment variable

export -n VARNAME

1. Display a list of exported environment variables

export -p

The tricky skills

1. Temporarily set an environment variable for a single command

VARNAME=value command

1. Export a variable to be available in sub-shells

export VARNAME=value

What needs to be noted

• The export command makes environment variables available to child processes, not to the current shell or parent processes.
• Changes made to environment variables using export are not permanent and will be lost when the terminal session is closed. To make changes permanent, update the appropriate configuration files like ~/.bashrc, ~/.bash_profile, or /etc/environment.

Conclusion

The export command is a powerful tool for managing environment variables in Linux. Understanding how to use it effectively will help you configure applications and processes to meet your specific needs. With practice, you'll be able to use the export command to create a more efficient and customized Linux environment.