unalias – Remove an alias set by alias

The unalias command is used to remove an alias that was previously set using the alias command.

The syntax for the unalias command is as follows:

unalias [option] [alias name]

Where [option] is an optional parameter to modify the behavior of the command, and [alias name] is the name of the alias to be removed.

Here is an example of how to use the unalias command:

$ alias ll='ls -l'
$ ll
total 0
$ unalias ll
$ ll
bash: ll: command not found

In this example, we first create an alias called ll that runs the ls -l command. We then run the ll command, which produces the same output as ls -l. Finally, we remove the ll alias using the unalias command and attempt to run ll again, resulting in an error message.

Options

The following table lists the available options for the unalias command:

Option Description
-a Remove all aliases.
-v Verbose mode. Display a message for each alias that is removed.

Troubleshooting Tips

If you receive an error message stating that the alias does not exist, double-check the spelling and capitalization of the alias name. If you are unsure whether an alias exists, you can list all currently defined aliases using the alias command without any arguments.

If you are having trouble removing an alias, try using the -v option to enable verbose mode. This will display a message for each alias that is removed, which can help you identify any issues.

Notes

Note that the unalias command only removes aliases that were set using the alias command. It will not remove any other type of command or function.

Also note that any aliases that are removed using the unalias command will not persist between sessions. To permanently remove an alias, you will need to remove the corresponding line from your shell configuration file (e.g. ~/.bashrc for the Bash shell).