tmux-terminal
Overview
Use tmux to drive interactive terminal sessions, including TUI workflows like ralph-tui. tmux lets you send keystrokes, capture screen output, and keep processes running between steps.
When to Use
- Testing
ralph-tuior any interactive CLI prompts - Managing long-running processes (web server, loops, watch mode)
- Capturing live terminal output for QA reports
- Interacting with applications that redraw the screen
Prerequisites
tmuxinstalled (pre-installed on macOS)
Verify:
bashtmux -V
Core Commands
Create a detached session:
bashtmux new-session -d -s <name>
Send commands (append Enter to execute):
bashtmux send-keys -t <name> "<command>" Enter
Capture screen output:
bashtmux capture-pane -t <name> -p
Kill session when done:
bashtmux kill-session -t <name>
Special Keys
Use send-keys with key names:
EnterC-c(Ctrl-C)C-d(Ctrl-D)TabEscapeUp,Down,Left,Right
Examples:
bashtmux send-keys -t <name> Up tmux send-keys -t <name> C-c
TUI Interaction Patterns
Start ralph-tui
bashtmux new-session -d -s ralph-tui tmux send-keys -t ralph-tui "cargo run -p ralph-tui" Enter
Navigate in TUI
bashtmux send-keys -t ralph-tui Down tmux send-keys -t ralph-tui Enter
Capture and parse the screen
bashtmux capture-pane -t ralph-tui -p -S -200
Use -S -200 to capture the last 200 lines when the screen is noisy.
Long-Running Process Management
- Start servers or loops in a tmux session to keep them alive.
- Use
capture-paneto confirm health (look for "listening" or "ready" text). - Stop cleanly with
C-cthenkill-session.
Example:
bashtmux new-session -d -s ralph-web tmux send-keys -t ralph-web "cargo run -p ralph-cli -- web" Enter tmux capture-pane -t ralph-web -p | rg -n "listening|ready" tmux send-keys -t ralph-web C-c tmux kill-session -t ralph-web
Notes
- Keep session names short and unique.
- Always clean up sessions to avoid leaking background processes.
- If output looks empty, wait briefly and capture again.


