My tmux config and a small tmux primer

Nov 13, 2014

It's been a little over a month since I started using tmux. Below, I'll try to explain most of my .tmux.conf, a bit of my current workflow using awesome + tmux and various cool stuff you can do with tmux. My latest .tmux.conf can be found on my dotfiles repo on GitHub.

Tmux config file

    unbind C-b set -g prefix C-a

As most people, I'm using C-a as my bind key.

    bind-key a send-prefix

On nested tmux sessions, I use C-a a to send commands to the second level tmux instance. Another popular choice is C-f, but it feels weird to me.

    bind-key C-a last-window

This is an old habit from screen, using C-a C-a to go to last active window.

    bind r source-file ~/.tmux.conf

Use C-a r to reload tmux configuration on the running session.

    bind-key -r j select-pane -D bind-key -r k select-pane -U bind-key
    -r H select-pane -L bind-key -r L select-pane -R

I'm using C-a j/k to move down/up in panes and C-a H/L to move left/right. The -r flag means the key can be repeated multiple times without having to press C-a again, e.g., C-a j j will move the cursor two panes down.

    bind-key -r l next-window bind-key -r h previous-window

Same as above C-a l/h for window navigation right/left.

    bind-key -r '=' resize-pane -U 5 bind-key -r '-' resize-pane -D 5
    bind-key -r '<' resize-pane -L 5 bind-key -r '>' resize-pane -R 5

An easy way to resize panes.

    bind-key m command-prompt -p "[ man page ]" "split-window 'exec man %%'"

This is one of my favorites that I picked up on #tmux on freenode. C-a m will open a prompt and ask for a man page to open a new bottom pane.

This is it in action.

    bind-key "'" split-window -h

I like to use C-a ' and C-a " for my horizontal/vertical splits.

    bind-key v copy-mode

Tmux has an amazing copy mode to scroll back up or copy text. The default way to enter said copy mode is C-a [, which I've remapped to =C-a v=.

    bind-key -t vi-copy 'v' begin-selection

To start selecting text the default key is Space, which again I've remapped to v to be in sync with vi.

    bind -t vi-copy y copy-pipe 'xclip -in > /dev/null'

When text is yanked in copy mode, it only exists in the context of the current session. The above remaps y to yank the selected text in copy mode and also save it on my clipboard using xclip.

    bind-key p paste-buffer

Remap C-a p to paste buffer instead of the default C-a ].

    setw -g mode-keys vi

Enable vi mode-keys, highly useful when selecting text in copy mode.

Here's a quick demo showcasing the above, using vi's gg and $ to move the cursor around, C-a v to enter copy mode and y=/=C-a p to yank and paste text.

    set -g set-titles on set -g set-titles-string '#(whoami)@#h -- #S'

Renames window titles on awesome's status bar.

    set -g status-utf8 on set -g status-bg colour241 set -g status-fg
    white set -g status-interval 60 set -g status-left-length 90 set
    -g status-right-length 60 set -g status-left
    "#[fg=Green]#(whoami)#[fg=white]::#[fg=yellow]#h" set -g
    status-justify left set -g status-right 'Session: #[fg=Cyan]#S -
    #[fg=white]Uptime:#[fg=Cyan]\ #(uptime | cut -d" " -f 4-5 | tr -d
    ,) - #[fg=white]Bat: [\ #[fg=Cyan]#(acpi | cut -d" " -f
    4-5)#[fg=white]]'

This is my tmux status bar config. It's pretty self-explanatory, the most interesting part is the last line where I use acpi to get the charge level of the battery and remaining charging time.

    set -g default-terminal "screen-256color"

Set the default terminal to use.

    set -g base-index 1 set -g pane-base-index 1

Start counting windows and panes from one and not zero.

    set -g history-limit 10000

The default setting is to save 2000 lines of history per pane, I've changed this to 10000.

Using tmux as a pdsh/clusterssh alternative

I normally use ansible to run ad-hoc commands in multiple hosts, but there are times when I want a quick and dirty solution or want to (cleanly) see the output of a command to a number of hosts. A lot of people use clusterssh to achieve the above, but I don't really like its use of xterm and the way it arranges windows, plus it semi-conflicts with awesome.

What I do instead, is run a script that opens a new tmux pane for every host, ssh to each host and set synchronize-panes on. With synchronize-panes, everything that is typed on one pane, is automatically sent to all panes in the same window. You can find the script here.

Here's a gif of it in action.

Or not, my netbook couldn't handle the gif creation, here's a pic instead with 7 panes active and ssh'ed.

End of part 1 (??)

That's all for now, hopefully there's gonna be a part two where I explain how I use tmux in conjunction with awesome.

PS. All the gifs in this page were created with ttygif.

Tags: software workflow