# tmux

Multiplexers can be used to reattach to previous sessions and manage clipboard content / session history. This means that when you close a terminal, the session still exists in the background and can be called to the foreground using your choice of tmux commands.

To reload you tmux config, press Ctrl+B and then : to bring up a command prompt, and type the following command in the prompt - 

```
:source-file ~/.tmux.conf
```

This will reload the changes made in your configuration and apply them to all active tmux sessions

Start tmux with the `-u` flag to enable utf8 support - 
```bash
tmux -u
alias tmux='tmux -u'
```

### Session / Server Management 
```bash
# Start the tmux server
# If ran while a tmux server is active, Tmux will not allow you to nest servers within eachother
tmux
tmux list-commands
# List active tty sessions tracked by the local tmux server
tmux list-sessions
# Interactive terminal to choose from previous sessions. Shows a thumbnail of the session in its last known state
tmux choose-session


# If you are running on a potato, you might need to use the following commands periodically to clean up your server as it will consume significant RAM.

# Kills all sessions, without killing the server.
# This command can confuse the interface / tmux status if you utilize session ID within your tmux status bar.
# ie.) If you run this on an active server within session ID 25, all sessions will be killed but your new session IDs will not reset to 1..2.. etc
# To fix this, restart your tmux server
tmux kill-session -a
# Kill tmux server, this will close ALL terminals and any WIP will be lost if it has not been saved.
tmux kill-server
```

#### Configuration / Status

Tmux has a very nice interface which can be customized to suit your needs and display the information relevant to your environment. This can be found in the `~/.tmux.conf` file but is recommended to be customized within the `~/.tmux.conf.local` file.

Some useful settings can be found below, taken from my [Dotfiles Repository](https://gitlab.com/shaunrd0/dot)

```bash
# .tmux.conf
#
# If symbols or powerline layout fail to appear...
#+ Check your terminal emulator font settings include these fonts
#+ Check that required fonts are installed
#
# Note: The use of 256colours in this file allows for portable color definitions between platforms and applications
#+ Changing to a different color interpretation may result in some apps displaying colors differently than others
#+ Vim plugin 'Colorizer' does not reflect the actual 256colour values
#+ See https://jonasjacek.github.io/colors/ for a full list of 256colours

# Mouse interaction
set -g mouse on

# Status bar location
set-option -g status-position top

# Status update interval
set -g status-interval 1

# Basic status bar colors
set -g status-style fg=colour240,bg=colour233

# Left side contents of status bar
set -g status-left-style bg=colour233,fg=colour243
set -g status-left-length 40
# Note: No bold required, no BG reveal produced by symbol gaps on left side
#+ Font: Powerline Consolas
#+ Some unicode characters may not appear when viewing this code via web browser
#+ Symbols below are 'left_hard_divider' and can be seen here (https://www.nerdfonts.com/cheat-sheet)
set -g status-left "#[fg=colour233,bg=colour100,bold] #S #[fg=colour100,bg=colour240,nobold]#[fg=colour233,bg=colour240] #(uname -m)#F  #[fg=colour240,bg=colour235]#[fg=colour240,bg=colour235] #I:#P #[fg=colour235,bg=colour233]#[fg=colour240,bg=colour233] #(uname -r)"
# Above, we use the #(COMMAND) syntax to print the output of COMMAND to the tmux status bar. 
# #I, #P, #F above are all tmux custom variables which can be found in the tmux manpage.

# Right side of status bar
set -g status-right-style bg=colour233,fg=colour243
set -g status-right-length 150
# Hide right bar entirely
#set -g status-right ""

# Note: Powerline font requires alternate of bold on right side
# Corrects gap on right of character that reveals BG color
#+ Font: Powerline Consolas
#+ Some unicode characters may not appear when viewing this code via web browser
#+ Symbols below are 'right_hard_divider' and can be seen here (https://www.nerdfonts.com/cheat-sheet)
set -g status-right  "#[fg=colour235,bg=colour233,bold]#[fg=colour240,bg=colour235,nobold] %H:%M:%S #[fg=colour240,bg=colour235,bold]#[fg=colour233,bg=colour240,nobold] %d-%b-%y #[fg=colour100,bg=colour240,bold]#[fg=colour233,bg=colour100,bold] #H "

# Window status (Centered)
set -g window-status-current-format "#[fg=colour255,bg=colour233]#[fg=colour100,nobold] #(whoami)@#H #[fg=colour255,bg=colour233,nobold]"
# Current window status
set -g window-status-current-style bg=colour100,fg=colour235
# Window with activity status
set -g window-status-activity-style bg=colour233,fg=colour245
# Window separator
set -g window-status-separator ""
# Window status alignment
set -g status-justify centre

# NOTE
# These are just SOME useful settings and not a complete configuration. See https://gitlab.com/shaunrd0/dot/blob/master/.tmux.conf for a full configuration that I use / edit frequently. It may look very different then the above, but uses the same ideas.
```

Want your current working directory to show some git repository information in your status bar? [Gitmux](https://github.com/arl/gitmux)


```
#(date) # Run a shell command in status bar 
#I 		# Window index 
#S 		# Session name
#W 		# window name
#F 		# window flags
#H 		# Hostname
#h 		# Hostname, short
#D 		# pane id
#P 		# pane index
#T 		# pane title
C-b [       # Enter scroll mode then press up and down
C-b ? 		# Show help
```



[tmux reference guide](https://referenceguide.dev/cheatsheet/tmux)