How to use alias

What is an alias?

An alias is an alternative name for a command or a group of commands. It allows you to run an instruction using a custom command in your command line interpreter. Using aliases can improve productivity and make the command line easier to use. Setting aliases for repetitive tasks or very complex commands can simplify your workflow and make it more efficient. Shell shortcuts, Git, project-specific aliases or NPM commands are some of the use cases where you can benefit from setting aliases.

You can set an alias like this:

alias ll='ls -alF'

If you want to persist your aliases over the current session, you need to store them in your shell config file, e.g.:~/.bashrc or ~/.zshrc. This file loads every time you open a new terminal session and it modifies your $PATH variable in the runtime.

If you edit your .zshrc file you will need to open a new terminal or do source ~/.zshrc to reload the shell cofiguration. If you are using OMZsh you can do it by running omz reload.

If you want to change the location of .zshrc you need to set it up in .zprofile file.

If you don't want to use an already cluttered .zshrc file and prefer to keep your aliases in a separate file, you can place them in the directory stored in your ZSH_CUSTOM system variable. Typically, this variable stores .oh-my-zsh/custom, so you can create a Zsh file there and name it as you prefer (e.g., custom_aliases.zsh). You can store all your aliases in this file just as you would in .zshrc, and your system will load them when .zshrc is sourced.

You can list all currently defined aliases using the command:

alias

Or you can check a specific alias:

alias ll

Alternatively, you can use type ll to know which command will be run. This command shows you if it's a shell built in, an alias or a binary.

Unsetting an Alias You can remove an alias with the unalias command:

unalias ll

How do aliases work?

Alias expansion:

1. Tokenization
2. Alias lookup: The shell first checks if the first word of your command matches an alias in some of your configuration files. If it does, it replaces that word with the alias's definition. This process is known as alias expansion.
3. Command execution

Alias precedence

By default, alias expansion is disabled in non-interactive shells (like scripts) to avoid unexpected behavior. However, if you have both a shell function and an alias with the same name, the alias will take precedence over the function.

The order of precedence is:

• Aliases (highest precedence)
• Shell functions
• Built-in commands (like echo, cd, etc.)
• Programs in PATH (executables)

Aliases in OMZsh

One of the greatest benefits of using OMZsh is all the predefined aliases that it provides. Some of the aliases and scripts you can use in OMZsh are:

🔹 General Command Shortcuts

Alias	Expands To	Description
ll	ls -lh	Long format with human-readable sizes
la	ls -lha	Show hidden files too
l	ls -l	Long format without hidden files
..	cd ..	Move up one directory
...	cd ../..	Move up two directories
....	cd ../../..	Move up three directories
c	clear	Clear terminal
md	mkdir -p	Create a directory and parent directories if needed
rd	rmdir	Remove empty directory

🔹 Other Useful Aliases

Alias	Expands To	Description
brewu	brew update	Update Homebrew and installed packages
npmi	npm install	Install dependencies in a Node.js project
ping	ping -c 5	Ping with 5 packets instead of infinite
yarn	yarn	Run Yarn package manager

🔹 Git Aliases (enabled by default in OMZ)

Alias	Expands To	Description
gst	git status	Show current repo status
gco	git checkout	Checkout a branch
gcmsg	git commit -m	Commit with message
gp	git push	Push changes
gl	git pull	Pull latest changes
ga	git add	Add files to staging
gaa	git add --all	Add all files to staging
gcm	git commit -m	Commit with message
gcb	git checkout -b	Create new branch and switch to it
gb	git branch	List branches
gd	git diff	Show changes

Your Git aliases are located in ~/.oh-my-zsh/plugins/git/git.plugin.zsh and you can find the full list at: OMZ Git aliases.