Tmux

tmux Session Control

Control tmux sessions by sending keystrokes and reading output. Essential for managing long-running processes and interactive terminal applications.

When to Use

✅ USE this skill when:

• Monitoring long-running processes in tmux
• Sending input to interactive terminal applications
• Scraping output from processes in tmux
• Navigating tmux panes/windows programmatically
• Managing multiple concurrent sessions

When NOT to Use

❌ DON'T use this skill when:

• Running one-off shell commands → use bash tool directly
• Starting new background processes → use bash with &
• Non-interactive scripts → use bash tool
• The process isn't in tmux

Common Commands

List Sessions

tmux list-sessions

Capture Output

# Last 20 lines of pane
tmux capture-pane -t session_name -p | tail -20

# Entire scrollback
tmux capture-pane -t session_name -p -S -

Send Keys

# Send text + Enter
tmux send-keys -t session_name "command" Enter

# Send Ctrl+C
tmux send-keys -t session_name C-c

Session Management

# Create new detached session
tmux new-session -d -s session_name

# Kill session
tmux kill-session -t session_name

# Check if session exists
tmux has-session -t session_name 2>/dev/null && echo "exists"

Examples

# Create a session and run a long process
tmux new-session -d -s myjob "node long-running-script.js"

# Check output after 10 seconds
sleep 10 && tmux capture-pane -t myjob -p -S -50

# Send interrupt
tmux send-keys -t myjob C-c

# Clean up
tmux kill-session -t myjob