Tmux - Terminal Multiplexer Cheatsheet

Overview

Tmux is a program for managing multiple terminal sessions, windows and panes. It allows to resize, move and switch between panes. There are other programs with similar functionality, e.g. Iterm2 for Mac Os or Terminator for various Linux distributions. But there is a con - all of them have no standardized way of using. They have different customization mechanisms and different way of control. And they are not cross platform. Tmux runs almost everywhere and allows single interface on different platforms. It allows to have same experience event in systems with no graphical UI.

Moreover Tmux makes it possible to run terminal sessions in the background and reattach them when needed. So you don't need to keep terminal open for program to run. Which is useful when working on a remote server.

Terminology:

To start working with Tmux let's define some basic terms:

window - is a Tmux screen. Only one window may be visible at one period of time;
pane - is a part of window. You are able to create many panes inside a window;

Basic Usage

To start Tmux enter following command in your terminal: tmux.

Most of Tmux command starts with a special prefix. By default it is Ctrl+b. But it can be changed, using customizations, so next it will be specified just simple as <Prefix>.

To exit type exit.

If there are multiple windows or panes opened and you need to close them all, press <Prefix> and type :kill-session.

Managing Sessions

tmux new -s <session-name> - create new session with specified name;
<Prefix> d - detach current session;
<Prefix> D - choose session to detach;
tmux ls - show existing sessions;
tmux attach -t <session-index> - attach to session by index;
tmux a -t <session-name> - attach to session with specified name;
tmux kill-session -t <session-name> - kill session by name;
<Prefix> s - list existing sessions;
<Prefix> $ - rename session;

Managing Windows

<Prefix>+c - creates new window;
<Prefix>+n - switch to the next window;
<Prefix>+p - switch to the previous window;
<Prefix>+<number> - go to window with number;
<Prefix>+w - list existing windows;
<Prefix>+, - rename window;
<Prefix>+f - find window;
<Prefix>+& - kill window;

Managing Panes

<Prefix>+" - split screen horizontally;
<Prefix>+% - split screen vertically;
<Prefix>+z - maximize current pane
<Prefix>+<Arrow Key> - allows to switch panes;
<Prefix> - while holding and using arrow keys allows to resize pane;
<Prefix>+o - swap panes;
<Prefix>+q - show pane numbers;
<Prefix>+x - kill pane;
<Prefix>+<Space> - toggle between layouts;

Copy Mode

Copy mode makes it possible to navigate pane content with page up, page down and arrow keys.

To enter the copy mode press combination <Prefix> [. To exit press q.

Other Commands

<Prefix>+t - clock;
<Prefix>+? - list shortcuts;

Configuration

Tmux is configured by a text file, located in ~/.tmux.conf. In order for new config to work Tmux must be forced to read configuration file:

tmux source-file ~/.tmux.conf

Some Adjustments

Set history limit: set -g history-limit 5000
To display correct colors: set -g default-terminal "screen-256color"
To change the default <Prefix>:
```
unbind C-b
set -g prefix C-a
```
Change pane switching to more vim-like combinations with <Alt>+<Shift>+<hjkl>: Here -n flag defines, that we don't want to use <Prefix> in shortcut.
```
bind -n M-Left select-pane -L
bind -n M-Right select-pane -R
bind -n M-Up select-pane -U
bind -n M-Down select-pane -D
```

Bindings for resizing panes:

bind -n M-_ resize-pane -Z
bind -T M-Down resize-pane -D 3
bind -n M-Up resize-pane -U 3
bind -n M-Left resize-pane -L 3
bind -n M-Right resize-pane -R 3

Show activity notifications from background windows:

setw -g monitor-activity on
set -g visual-activity on

It is often helpful to open new pane in current window, when working on some project in the same working directory. But by default Tmux opens new windows and panes in user's home directory. To change this use following configuration:
```
bind c new-window -c "#{pane_current_path}"
bind '"' split-window -c "#{pane_current_path}"
bind % split-window -h -c "#{pane_current_path}"
```

Customization

Install tmux package manager:

git clone https://github.com/tmux-plugins/tpm ~/.tmux/plugins/tpm