tmux configuration

Having multiple windows that persist through sessions is a very nice feature when working on various things simultaneously. Simply dedicate a screen session to each task, and you can resume at the point you left off each time you switch context. tmux is an alternative to screen that has a number of extra features.

A good introduction to tmux can be found on Medium

tmux configuration

Below is a sample tmxu configuration file. By default, tmux will read ~/.tmux.conf, although you can specify an alternative when starting tmux using the -f flag.

# remap prefix to Control + a
set -g prefix C-a
# bind 'C-a C-a' to type 'C-a'
bind C-a send-prefix
unbind C-b

# split panes using | and -
bind | split-window -h -c "#{pane_current_path}"
bind _ split-window -v -c "#{pane_current_path}"
unbind '"'
unbind %

# reload config file (change file location to your the
# tmux.conf you want to use)
bind r source-file ~/.tmux.conf

# set inactive/active window styles
set -g window-style 'fg=colour247,bg=colour236'
set -g window-active-style 'fg=colour250,bg=colour232'

#pane border
set -g pane-border-bg colour235
set -g pane-border-fg colour238
set -g pane-active-border-bg colour236
set -g pane-active-border-fg colour51

# use vi keyboard shortcuts in copy mode
setw -g mode-keys vi

# switch mouse support on
set -g mouse on

It sets the prefix to C-a which makes switching between tmux and screen less of an issue. It also redefines the default bindings for splitting a pane vertically or horizontally since these are easier to remember. In addition, new panes are opened in the same directory the pane is in when you split it, rather than in the directory tmux was started in.

tmuxp: a tmux session manager

The tmuxp session manager lets you specify tmux sessions in YAML or JSON files so you can easily start a session with one or more windows and your favorite layout. In each pane, one or more bash command can be executed to initialize your working environment.

Below you’ll see a sample session configuration file.

session_name: dev_py
windows:
- window_name: dev
  layout: main-vertical
  options:
      main-pane-width: 90
  panes:
    - shell_command:
        - vim
      focus: true
    - shell_command:
        - module load conda
        - source activate py37
        - clear
    - null

This defines a session dev_py with a single window, named dev. The main pane is vertical, and has a width of 90 characters (to accommodate a vi mwindow with decoration and 80 character width). In the main pane, vim is started. The second pane loads a module, sources a conda environmet for Python development, anc clears the screen. The third panel doesn’t execute commands.

The vim editor will take up the left half of the screen, while the right-top pane will have a conda environment ready to execute Python scripts. The right-bottom window can be used to do some shell commands.

Session files stored in the ~/tmuxp/ directory can be loaded by name, So if the file above is stored in that directory, you can load this session by ty typing:

$ tmuxp load dev_py