TMUX - A Terminal Multiplexer

Speaker: Nick Diesslin

Twitter handle: @ndiesslin

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Key Takeaways

• What is TMUX?
  • Alternatives
• Benefits
• Getting started
• How to configure
• Plugins
• How to use
• Commands
• Use cases
• Expanding upon TMUX, creating widgets

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What is TMUX?

• TMUX is a terminal multiplexer
• TMUX runs sessions, sessions contain windows and windows contain panes
• The biggest benefit is being able to run multiple terminal commands at the same time
• TMUX is for UNIX like operating systems

Alternatives to TMUX

TMUX is recommended, but to be fair there are other terminal session managers available

• Screen (Older GNU terminal session manager)
• Byobu

Benefits

• The terminal will now run sessions, which can be detached and attached to a terminal window
• Tabs, split screens in session
• Configurable
• Zooming in panes
• Saved and restored sessions (with plugins)

Getting Started

• TMUX is available with most package managers
• Mac

brew install tmux

• Debian based linux

apt-get install tmux 

• Then type tmux to start a session

tmux

• TMUX has what is called a prefix key, this is the keyboard combination you will need to interact with TMUX. By default it is ctrl+b

ctrl+b

How to configure

• TMUX will load configurations based off of the .tmux.conf file in your home directory (~)
• You can steal someone's configuration from the internet to start off in a better place, but you will want to review in case there are any unfamiliar keybindings
• Default tmux command prefix: Most of the users on the internet remap ctrl+b to ctrl+a
• TMUX uses 256 color palette
• To see the colors available for configurations run this script

for i in {0..255}; do
    printf "\x1b[38;5;${i}mcolour${i}\x1b[0m\n"
done

• Status bar can be beneficial for adding important information, like server uptime or current time.
• This is a great resource for making TMUX more usable: https://www.hamvocke.com/blog/a-guide-to-customizing-your-tmux-conf

Plugins

• Plugin manager tpm (easier way to manage plugins): https://github.com/tmux-plugins/tpm

• TMUX yank (copying to clipboard): https://github.com/tmux-plugins/tmux-yank

• TMUX resurrect (persistent sessions after restarts): https://github.com/tmux-plugins/tmux-resurrect

• TMUX continuum (continuous saving of tmux environment.): https://github.com/tmux-plugins/tmux-continuum

• TMUX sensible (standardized tmux settings): https://github.com/tmux-plugins/tmux-sensible

• Full list of plugins here: https://github.com/tmux-plugins

How to use

• Creating windows
• Splitting windows into panes
• Resizing panes
• Zooming in and out of pane

Commands

Sessions

• Load tmux session

tmux

• Load tmux session with name - beneficial if multiple people work on same machine

tmux new -s mysession

• Show running tmux sessions

ctrl+b s

• Detach from session

ctrl+b d

Windows/Tabs

• Create new window

ctrl+b c

• Close current window

ctrl+b &

Panes

• Split pane vertically

ctrl+b %

• Split pane horizontally

ctrl+b "

• Switching panes

ctrl+b (any arrow key for direction)

Copy Mode

• Copy mode puts the session in a mode that allows you to interact with your terminal session in a similar way to vim. This is especially helpful with things like searching logs.

• Enter copy mode

ctrl+b [

• Arrow up and down to go through lines in sessions, or you can use j to move down or k to move up like in vim.

• Visually select a line

Shift+v

• Copy highlighted line

y

Giant clock

ctrl+b t

Use cases

• Comparing multiple servers in split view
• Saving and restoring sessions for saving time with local development
• Multiple users working on same server, each could spin up their own TMUX session
• Creating a session with a command that you can check in on

Expanding on TMUX

Creating a status widget

• TMUX can run any script and display this in the status bar. This means you can really use any scripting language to create some sort of status bar widget.

• Simple example of something that could be used in statusbar

touch ~/pingtest.sh

echo "ping google.com" >> ~/pingtest.sh

• Add this to statusbar

#(sh ~/pingtest.sh)

• I've created a simple node weather script that returns the weather to be used in the status bar https://github.com/ndiesslin/TMUX-weather-widget

Running a command with a TMUX session

• TMUX can be helpful if you need to run a command to check in on later, this could be on a server for example.

tmux new-session -d -s temporary_session 'sh ~/pingtest.sh'

• Attach to our session we created

tmux attach -t temporary_session