How to Copy and Paste with Tmux on Mac OSX

Posted in: tmux.

UPDATE (2013/07/23): What follows is only necessary prior to tmux version 1.8. If you’re using tmux 1.8 or later, check out Thoughtbot’s notes on using copy-pipe.

Step 1: Install reattach-to-user-namespace

If you’re using Homebrew:

brew install reattach-to-user-namespace

If not, go compile the code yourself.

Step 2: Configure the Deafult Shell Command

Open your Tmux config file (usually ~/.tmux.conf) and add the

set-option -g default-command "command -v reattach-to-user-namespace >/dev/null 2>&1 && reattach-to-user-namespace -l $SHELL || $SHELL -l"

Now, every time you open a new window or pane, Tmux will will attempt to use
reattach-to-user-namespace before starting your shell.

Step 3: Configure Copy-Mode Bindings

Assuming you’re using the vi keybindings, add the following to your config:

bind -t vi-copy v begin-selection
bind -t vi-copy c copy-selection
bind y send-keys c\;\
       run-shell "tmux save-buffer - | reattach-to-user-namespace pbcopy"

Here’s what each line does:

  1. Just for convenience; pressing v will now begin a selection.
  2. Provides a key binding that we’ll use in line 3.
  3. Provides a global keybinding (prefix-y) that invokes copy-selection and then pipes the buffer into pbcopy.
    Unfortunately, we have to use a global keybinding here because tmux cannot bind multiple commands to any key under a specific key-table, only globally.

Et voila - you can now use prefix-y to copy text to the clipboard.

If you’re using emacs bindings, you might want to use something like this

# unbind M-w; we'll use prefix-M-w instead
unbind -t emacs-copy M-w
bind -t emacs-copy c copy-selection
bind M-w send-keys c\;\
       run-shell "tmux save-buffer - | reattach-to-user-namespace pbcopy"