Introduction
In the world of Unix and Linux, the command line is king. And when it comes to command line shells, Zsh (short for Z Shell) is one of the most powerful and flexible options available.
For Unix power users who want to take their skills to the next level, mastering Zsh is a must. Here are 10 essential features to get started with.
1. Tab Completion
One of the most useful features of Zsh is its tab completion. Simply press the Tab key while typing a command or filename, and Zsh will suggest possible options based on what you’ve typed so far.
For example, to list all files that start with the letters „ab“ in the current directory, you could type:
ls ab[TAB]
Zsh will then show you all files (and directories) in the current directory that start with „ab“.
2. Globbing
Globbing is a powerful feature that allows you to select files and directories based on complex patterns. For example, to list all files in the current directory and its subdirectories that have the extension „.txt“, you could use the following command:
ls **/*.txt
The double asterisk (**) means „match any number of directories and subdirectories“. The forward slash separates directories from the filename. And the „*.txt“ means „match any filename that ends with .txt“.
3. Extended Globbing
Zsh also supports extended globbing, which allows you to use even more complex patterns to select files and directories. For example, to list all files that have a single letter as their filename (e.g. „a“, „b“, „c“, etc.), you could use the following command:
ls [[:alpha:]]
The „[[:alpha:]]“ means „match any character that is a letter“.
4. Brace Expansion
Brace expansion is a feature that allows you to quickly generate a list of values based on a pattern. For example, to create 10 text files named „file1.txt“, „file2.txt“, „file3.txt“, and so on, you could use the following command:
touch file{1..10}.txt
The „{1..10}“ means „generate the numbers from 1 to 10“. Zsh will then automatically expand this pattern and create the 10 text files.
5. History Expansion
Zsh also has a powerful history feature that allows you to easily reuse and modify previous commands. For example, to repeat the last command that started with the letters „ls“, you could type:
!!
The double exclamation mark means „repeat the last command“. If you wanted to modify the last command before running it, you could use the following command:
!ls:s/ab/cd/
This means „replace the first instance of ‚ab‘ in the last ‚ls‘ command with ‚cd'“.
6. Aliases
Zsh allows you to create aliases for commands to make them easier to remember and type. For example, to create an alias for the long and complex „grep“ command, you could use the following command:
alias grep='grep --color=auto'
This creates an alias called „grep“ that automatically adds the „–color=auto“ option to the command.
7. Functions
Zsh also allows you to create custom functions that can perform complex tasks or automate repetitive commands. For example, to create a function called „backup“ that makes a compressed backup of a file, you could use the following code:
function backup() {
tar cvzf "$1".tgz "$1"
}
This creates a function called „backup“ that takes one argument (the name of the file to be backed up) and compresses it into a .tgz file.
8. Autoload
Zsh also has a feature called „autoload“ that allows you to load new modules and functions only when they’re needed. This can help to speed up your shell and conserve memory. For example, to autoload the „git“ command only when it’s used for the first time, you could use the following command:
autoload -Uz compinit && compinit
autoload -Uz bashcompinit && bashcompinit
autoload -Uz git
This loads the necessary modules and then autoloads the „git“ command.
9. Prompt Customization
Zsh allows you to fully customize your prompt, including colors, icons, and text. For example, to create a custom prompt that shows your current directory and Git branch, you could use the following command:
PS1='%B%F{cyan}%n@%m:%f%F{green}%1~%f $(git_prompt_info) %#%b '
This creates a prompt that shows your username, hostname, current directory, Git branch (if you’re in a Git repository), and the command prompt symbol (# or $).
10. Plugins
Zsh also has a vast library of plugins that can enhance its functionality even further. These plugins can be easily installed and activated using tools like Oh My Zsh. Some popular plugins include autojump (which allows you to quickly navigate your filesystem), zsh-syntax-highlighting (which highlights commands and syntax errors in color), and z (which allows you to quickly jump to frequently-used directories).
Conclusion
As you can see, Zsh is an incredibly powerful and flexible shell that can help Unix power users take their skills to the next level. With features like tab completion, globbing, extended globbing, brace expansion, and more, Zsh is a must-learn tool for anyone who spends time in the command line. So why not give it a try and see what it can do for you?