tmux

Additional Notes

tmux is a terminal multiplexer that lets you run multiple terminal sessions within a single window. It allows you to split the terminal into panes, create multiple windows, detach and reattach sessions, and share sessions with other users. It is similar to GNU Screen but with a cleaner configuration model and modern features.

Each tmux session can have multiple windows, and each window can be split into multiple panes. Sessions persist even when the terminal is closed, so you can detach from a session at work and reattach from home. Tmux is controlled entirely via keyboard shortcuts, using a prefix key (default Ctrl+b) followed by a command key.

Syntax

tmux [command] [options]

Key Sessions Commands

• new or new-session: Create a new session.
• ls or list-sessions: List existing sessions.
• attach or attach-session: Attach to an existing session.
• detach or detach-session: Detach the current session.
• kill-session: Terminate a session.
• switch: Switch to another session.

Parameters

• options: Flags that change how tmux behaves.
• target: Optional file, device, interface, user, service, or command target when the command supports one.

Common Options

• -S socket-path: Specify an alternative socket path for the tmux server.
• -L socket-name: Use an alternative socket name (defaults to default).
• -f config-file: Load an alternative configuration file.
• -u: Operate in UTF-8 mode.

Default Key Bindings (prefix Ctrl+b)

• %: Split pane vertically.
• ": Split pane horizontally.
• Arrow keys: Switch to pane in that direction.
• c: Create a new window.
• n / p: Next / previous window.
• ,: Rename the current window.
• &: Kill the current window.
• d: Detach from the session.
• [: Enter copy mode (scroll with arrows/PgUp/PgDn).
• ]: Paste from copy buffer.
• :: Enter a tmux command.
• s: Interactively select a session.
• w: Interactively select a window.
• t: Show a clock in the current pane.

Examples

tmux new -s mysession

Create and attach to a new session named mysession.

tmux ls

List all running tmux sessions.

tmux attach -t mysession

Reattach to the session named mysession.

tmux new -s work -d
tmux send-keys -t work "vim" Enter
tmux attach -t work

Create a detached session, start Vim in it, then attach.

tmux kill-session -t mysession

Terminate a session.

Configuration

Tmux reads ~/.tmux.conf on startup. Example:

set -g mouse on
set -g default-terminal "screen-256color"
bind | split-window -h
bind - split-window -v

Practical Notes

• Detach with Ctrl+b d and close the terminal; the session keeps running.
• Rename sessions meaningfully so tmux ls is useful.
• The mouse on option enables click-to-select panes, resize panes, and scroll.
• Copy mode (Ctrl+b [) lets you scroll back and select text with the keyboard.
• Tmux respawns the shell even if the shell exits; you can configure it to close the pane on exit.
• Use tmux kill-server to kill all sessions and the tmux server.