alias command in linux - Scaler Topics

Overview

In the Linux ecosystem, an indispensable feature that aids in enhancing productivity is the alias command. The alias command in Linux is a method of reducing typing time by substituting a longer command sequence with a shorter one. This utility not only saves time but also reduces the risk of typing errors.

Syntax of alias Command in Linux

The basic syntax of the alias command in Linux is as follows:

Where:

alias: This is the command keyword which signals the interpreter to perform an alias operation.
name='command': Here, 'name' is the alias name and 'command' is the Linux command string it should represent. The command string must be in quotes.

Options in alias Command in Linux

-p: This option prints the list of currently defined aliases.

For example -
Output:
This command will list all the defined aliases in the current shell.

Example Usages

Setting an alias for a simple command:
Explanation: This will set the alias 'll' to perform the command 'ls -la'. So, when you type 'll', it will list all the files and directories including hidden ones in long format.
Removing an alias:
Explanation: This command will remove the alias 'll' that was previously set.

Tips

Aliases are shell-specific and non-permanent. If you want to make them permanent across sessions, you can add them to shell configuration files such as .bashrc, .bash_profile, or .zshrc.
Complex commands can also be aliased by enclosing them within single quotes in the alias command.

Advanced Use Cases of alias Command in Linux

Create an alias to navigate to a specific directory:
Explanation: This command creates an alias 'project' that changes the current directory to '/home/user/MyProject/' when invoked.
Create an alias to show the usage of disk space by each directory:
Explanation: This command sets an alias 'du' that when invoked, shows the disk usage by each directory in the current directory in human-readable format.
Create an alias with a pipe and multiple commands:
Explanation: This command creates an alias 'lf' that lists all text files in long format in the current directory.

Conclusion

The alias command in Linux is a handy tool to create shortcuts for lengthy or complex command sequences.
While the alias command greatly enhances productivity, it is vital to ensure that the alias names don't collide with existing command names.
Aliases defined in a session are temporary. To make them permanent, add them to shell configuration files.