How to copy text from one pane – MacOS/Tmux/Alacritty


My problem? I only want to copy text from one tmux pane, not across two.

But I was finding that my mouse was failing me, and I knew there had to be a better way than just closing out my panes and only having one open. My journey on understanding terminals, shells, editors, and how to use them correctly has been rocky, but I have been feeling in a good place lately. The current setup that I am using is bash shell (starship shell prompt for that added sparkle), Alacritty terminal, Neovim editor, and Tmux for running multiple terminals. I had gotten this all configured, which probably took too much time. Debugging your developer setup is a considerable learning experience, but developers (meaning me) sometimes (all the time) make it more complicated than it needs to be. I probably didn’t need to throw in attempting to theme everything too, but I like my consistent look.

In my search to figure out how to copy the text on one pane, some Linux solutions were close to what I needed but not 100% the way there. This setup got me all the way there with a solution that should fit nicely in my vim workflow.

The suggested Linux setup is a good start but does not work great for MacOS

 bind-key -T copy-mode-vi v send-keys -X begin-selection
 bind-key -T copy-mode-vi y send-keys -X copy-selection
 bind-key -T copy-mode-vi r send-keys -X rectangle-toggle

For MacOS, add the following onto your tmux configuration (for ex. at ~/.tmux.conf). This solution came from a superuser post from user jeremysprofile.

setw -g mode-keys vi
set -g set-clipboard off
bind-key -T copy-mode-vi v send-keys -X begin-selection
# bind y key in copy mode to select and copy to system clipboard
bind-key -T copy-mode-vi y send-keys -X copy-pipe-and-cancel "pbcopy"
bind-key -T copy-mode-vi MouseDragEnd1Pane send-keys -X copy-pipe-and-cancel "pbcopy"

The configuration will add some vi key bindings, and then to supercharge tmux copy mode. For copying and pasting, reach for typical vim keybindings. Start with v to select the text, then y to copy/yank the text. Then the text is in your copy buffer and ready for pasting.

Let’s see our new bindings in action.

Hit your terminal, start up tmux (tmux source ~/.tmux.conf ) and make sure to refresh your config if you already have tmux open.

Split your pane (tmux default keys C-b ")

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Load up some text on either side. I am looking at two readme files, one that I loaded up in vim and one that is just cat on the terminal.

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Now attempt to use your mouse to highlight some text. You will notice that both sides will highlight.

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Frustrating if you want the output from just the right side! Let’s use the new keybindings we added to the tmux configuration instead.

Switch over to tmux scroll mode (C-b [), use your arrow keys to move around, and when you are on the text that you want to copy, use v to make your selection.

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What’s this? Only text selected on one side? Perfect! Copy the text using y , and it is ready to put where you need it. In my case, moving to my left pane (C-b then left arrow ), and then pasted (vim p) into my other readme.

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Now we have a reusable, memorable solution for grabbing text in a single tmux pane!