How to delete an environment variable in Linux?

Deleting Environment Variables in Linux

In the Linux operating system, environment variables are a crucial part of the system's configuration and can be used to store various settings, paths, and other important information. These variables are accessible to all running processes and can be modified or deleted as needed.

To delete an environment variable in Linux, you can follow these steps:

Step 1: Identify the Environment Variable

The first step is to identify the environment variable you want to delete. You can list all the currently defined environment variables using the following command:

env

This will display a list of all the environment variables and their corresponding values.

Step 2: Delete the Environment Variable

Once you have identified the environment variable you want to delete, you can use the unset command to remove it from the system. The syntax for the unset command is as follows:

unset VARIABLE_NAME

Replace VARIABLE_NAME with the name of the environment variable you want to delete.

For example, if you want to delete the PATH environment variable, you can use the following command:

unset PATH

After running this command, the PATH environment variable will be removed from the current shell session.

Step 3: Verify the Deletion

To verify that the environment variable has been deleted, you can use the env command again to list the current environment variables. The deleted variable should no longer be present in the output.

env

Deleting Environment Variables Permanently

The steps above only remove the environment variable from the current shell session. If you want to delete the environment variable permanently, you need to modify the appropriate configuration file(s) where the variable is defined.

The location of the configuration file(s) may vary depending on your Linux distribution and the shell you are using (e.g., Bash, Zsh, etc.). Common locations include:

• /etc/environment: This file is used to set system-wide environment variables.
• ~/.bashrc or ~/.bash_profile: These files are used to set user-specific environment variables for the Bash shell.
• /etc/profile or /etc/profile.d/: These files are used to set system-wide environment variables for the Bash shell.

After making the necessary changes to the configuration file(s), save the file(s) and either log out and log back in or run the following command to apply the changes:

source /path/to/configuration/file

This will ensure that the environment variable is deleted permanently.

Conclusion

Deleting environment variables in Linux is a straightforward process. By using the unset command, you can remove an environment variable from the current shell session. To delete the variable permanently, you need to modify the appropriate configuration file(s) where the variable is defined. Remember to verify the deletion by listing the environment variables using the env command.