Why Tmux⁉️

Every software engineer, or people working with software development, have had some sort of interaction with a terminal. Now, terminals are great! If one really masters it, there is no need to use your default OS file explorer to get around files that you need.

However, I personally find it quite chaotic to use many many many terminal windows when trying to work on a single project. The problem of now knowing which terminal window has what can be mind-boggling, and if you have even 5 of such windows, you are already at a trouble to know which terminal has what process running.

Enter Tmux

What is Tmux❓

Tmux is a terminal multiplexer for Ubuntu (and other Linux-based operating systems). It allows users to run multiple terminal sessions within a single terminal window and switch between them easily. Tmux also allows users to detach and reattach sessions, which makes it useful for running long-running commands or keeping a session open even when you are not actively using it.

In short, we can split a single terminal into many terminal windows, without having to open many terminal windows for each separate tasks. We can also name our terminal sessions in Tmux, which makes it easier to keep track of which terminal window is for which job. The detach and reattach functions are also super convenient, since we can temporarily suspend our terminals and resume back to them whenever we want.

So, let’s now see how one would go about using Tmux!!

Installing Tmux

To install Tmux on Ubuntu, you can use the following command in your terminal:

sudo apt-get install tmux

Once finished, you should have Tmux installed on your machine. Once installed, you can start Tmux by running the command Tmux in the terminal. Once you are in Tmux, you can use various key commands to navigate and manage your sessions, windows, and panes. You can find more information on how to use Tmux by running man Tmux in the terminal. However, I can help you get started with a few useful things to move around tmux.

Tmux shortcuts

Create Splits

Once you type tmux in your favourite terminal, you should see the terminal on the default directory of your machine. From here, type in your first command using:

: ctrl + b %

When you type the colon :, look at the bottom of the window to see the prompt changing to :. The ctrl + b is the default prefix that Tmux has when you want to execute Tmux commands in a window. The % symbol is used to split the terminal horizontally. Similarly, replacing % with ' will split the window vertically.

Now that you have your first split, start typing your commands in any of the splits. To switch between the terminal windows, there are two ways:

  1. prefix + <direction>: Here prefix is the default prefix Ctrl + b and direction is one of the arrow keys (up, down, left, or right) to move the focus to the corresponding pane.
  2. prefix + o: To move the focus to the next pane in the current window.
  3. prefix + { or prefix + } : To move the focus to the next or previous pane in the current window
  4. prefix + q + <pane-number>: Prompts the number of the panes on screen, and you choose the number where you want to switch.

Resize Windows

We can also resize our splits that we created with the following commands:

  1. prefix + <direction> + <arrow key>: to resize the current pane in the specified direction.
  2. prefix + <direction> + <arrow key> + <Shift>: to resize the current pane more quickly in the specified direction.

Tmux configuration file

The default prefix that Tmux provides is a bit unnatural to many programmers, and this can be fixed very easily. To fix this, you just need to create a tmux.conf file in the root system, and add the following line there:

set-hook -g after-new-session "source-file ~/.tmux.conf" 

unbind-key C-b 
set-option -g prefix C-<enter new prefix key here>
bind-key C-g send-prefix

Once you enter your favourite prefix key in the set-option command, you will have changed your prefix. For the changes to appear, either restart tmux server, or type the following in any of the tmux panes:

: source ~/.tmux.conf

This will source your changes from the config file, and your prefix should be changed.

Generally, these are the configuration files that I have seen programmers use quite often:

set-hook -g after-new-session "source-file ~/.tmux.conf"

unbind-key C-b
set-option -g prefix C-g
bind-key C-g send-prefix

set-window-option -g mode-keys vi
bind e setw synchronize-panes on\; display-message "Panes are synchronized"
bind E setw synchronize-panes off\; display-message "Panes not synchronized"

bind h select-pane -L
bind j select-pane -D
bind k select-pane -U
bind l select-pane -R

To know what each of them do, type the prefix key that you set, and then the alphabet following the bind keyword in the above configuration.

This can be used as a good starting point for your tmux.conf file.

Congratulations

You are now a pro terminal user who uses tmux to set up their workflow. Hopefully, you should soon see a boost in your productivity, and will also fall in love with your terminal :)

Until next time!!