crossterm

Crossterm - Terminal Manipulation Reference

Source: https://docs.rs/crossterm/latest/crossterm/
Crate: crossterm

Role in Pour

Crossterm is the backend for ratatui. It handles raw terminal I/O, event capture, and screen management.

Terminal Setup/Teardown

use crossterm::{
    execute,
    terminal::{enable_raw_mode, disable_raw_mode, EnterAlternateScreen, LeaveAlternateScreen},
};

// Setup
enable_raw_mode()?;
execute!(std::io::stdout(), EnterAlternateScreen)?;

// Teardown
disable_raw_mode()?;
execute!(std::io::stdout(), LeaveAlternateScreen)?;

Note: ratatui::init() and ratatui::restore() handle this automatically.

Event Handling

use crossterm::event::{self, Event, KeyCode, KeyEvent, KeyModifiers};

// Blocking read
if let Event::Key(key) = event::read()? {
    match key.code {
        KeyCode::Char('q') => { /* quit */ }
        KeyCode::Char('c') if key.modifiers.contains(KeyModifiers::CONTROL) => { /* ctrl+c */ }
        KeyCode::Enter => { /* submit */ }
        KeyCode::Tab => { /* next field */ }
        KeyCode::BackTab => { /* prev field */ }
        KeyCode::Up => { /* navigate up */ }
        KeyCode::Down => { /* navigate down */ }
        KeyCode::Backspace => { /* delete char */ }
        KeyCode::Char(c) => { /* type character */ }
        KeyCode::Esc => { /* cancel */ }
        _ => {}
    }
}

// Non-blocking poll
if event::poll(std::time::Duration::from_millis(100))? {
    if let Event::Key(key) = event::read()? {
        // handle key
    }
}

Key Types

Type Description
Event Top-level event enum: Key, Mouse, Resize, Paste, FocusGained/Lost
KeyEvent Contains code: KeyCode, modifiers: KeyModifiers, kind: KeyEventKind
KeyCode Enum: Char(char), Enter, Esc, Tab, BackTab, Backspace, Up/Down/Left/Right, F(u8), etc.
KeyModifiers Bitflags: SHIFT, CONTROL, ALT, SUPER, NONE
KeyEventKind Press, Repeat, Release

Execution Macros

// Immediate flush (for single commands)
execute!(stdout, command1, command2)?;

// Queued (for batch rendering -- ratatui uses this internally)
queue!(stdout, command1, command2)?;
stdout.flush()?;