zsh new line prompt after each command

Mastering Zsh: Newline Prompts After Each Command

Learn how to configure your Zsh shell to display a new line prompt after every command, enhancing readability and command-line experience.

The Zsh shell is highly customizable, offering a plethora of options to tailor your command-line experience. One common desire among users is to have the prompt appear on a new line after each command execution. This can significantly improve readability, especially when dealing with long commands or complex output. This article will guide you through the necessary configurations to achieve a new line prompt in Zsh, explaining the underlying concepts and providing practical examples.

Understanding Zsh Prompts

Zsh uses special parameters to define its prompts. The primary prompt is controlled by PROMPT (or PS1), and the right-aligned prompt by RPROMPT (or PS2). The key to forcing a new line after a command lies in manipulating the PROMPT variable to include a newline character at the end of its definition. This ensures that after Zsh displays the prompt and you type a command, the next prompt will automatically start on a fresh line.

flowchart TD
    A[Zsh Command Execution] --> B{Command Output?}
    B -->|Yes| C[Display Output]
    C --> D[Prompt Redraw]
    B -->|No| D[Prompt Redraw]
    D --> E{"PROMPT" Variable}
    E -->|Contains \n at end| F[New Line Before Prompt]
    E -->|No \n| G[Same Line as Last Output]
    F --> H[User Input]

Flowchart illustrating how Zsh handles prompt redraws based on the PROMPT variable.

Implementing a New Line Prompt

To implement a new line prompt, you need to modify your ~/.zshrc file. This file is executed every time Zsh starts, allowing you to define custom settings and functions. The core idea is to append a newline character (\n) to your PROMPT variable. You can also use \r for a carriage return, which moves the cursor to the beginning of the current line, but \n is generally preferred for clarity.

# Basic prompt with a newline
PROMPT='%n@%m %~\n$ '

# More advanced prompt with color and newline
PROMPT='%F{green}%n@%m%f %F{blue}%~%f\n$ '

Examples of Zsh PROMPT configurations with a newline character.

Customizing Your Prompt Further

Beyond just adding a newline, Zsh offers extensive prompt customization using various escape sequences. These sequences allow you to display information like the current user, hostname, current directory, Git status, and more. Combining these with the newline character gives you a powerful and informative prompt.

# Example with Git status and newline
autoload -Uz vcs_info
precmd_vcs_info() { vcs_info }
precmd_functions+=( precmd_vcs_info )
setopt PROMPT_SUBST
PROMPT='%F{green}%n@%m%f %F{blue}%~%f${vcs_info_msg_0_} \n$ '

A more complex Zsh prompt including Git status and a newline.

1. Open your Zsh configuration file

Use your preferred text editor (e.g., nano, vim, code) to open ~/.zshrc. If the file doesn't exist, you can create it.

2. Locate or define your PROMPT variable

Look for lines starting with PROMPT= or PS1=. If you find one, modify it. If not, you can add a new line to define your prompt.

3. Add a newline character

Append \n to the end of your PROMPT string, just before the final prompt character (e.g., $, %, >). For example, change PROMPT='%n@%m %~ $ ' to PROMPT='%n@%m %~\n$ '.

4. Save and apply changes

Save the ~/.zshrc file. Then, in your terminal, run source ~/.zshrc or simply open a new terminal session to see the changes.