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I was trying to learn how to use the bind-key [-cnr] [-t key-table] key command [arguments] better, but was having some trouble figuring out what "valid keys" are for bind-key command.

I tried doing man tmux and Google too, but I couldn't find anything useful.

  • How can I figure out what the syntax for valid keys are?
  • Is there a help command or a man page for this?
  • Maybe I don't know the technical term for this valid keys, is there a term for these keys so that I can do a better google search?

For example, I was trying to figure out what the following remapping of commands meant:

bind-key -n M-S-Left resize-pane -L 2
bind-key -n M-S-Right resize-pane -R 2
bind-key -n M-S-Up resize-pane -U 2
bind-key -n M-S-Down resize-pane -D 4

The -n was easy to find in the man page (doesn't need prefix). But I can't figure out what M-S-Left key means.

I am guessing that its mapping shift and the left arrow plus whatever M means to the resize-pane -L 2 command.

  • How do I figure out what M means?
  • What if I wanted control + whatever key I wanted. Is control = C ?
  • How can I figure this out without just trying random keys on my keyboard until something works?
  • Also, how do I confirm, figure out if I am not mapping it to a key set that is already used?
  • Is there such a thing as "show all aliases" or something?
  • As an addition to the question, are these valid keys the same as the ones for vim?

The thing is that vim seems to have a different scripting for its own language since it sometimes require and stuff.

share|improve this question
M stands for Meta which is the Alt key on a PC keyboard. – schaiba Jun 30 '14 at 18:11
thanks for that particular example! But it would be nice to know in general how to be able to figure this type of things on my own without having to come to stachexchange to ask for each key that I need. – Pinocchio Jun 30 '14 at 18:16
I hope I answered your questions :). I'll try to find an answer for the vim questions :). – polym Jun 30 '14 at 18:41
yes it did! that was awesome! Thanks! :) It didn't let me accept cuz u answered so soon after I posted the question! lol :) thnx again. :) – Pinocchio Jun 30 '14 at 18:42
Haha no probs :). tmux is awesome! – polym Jun 30 '14 at 18:48
up vote 9 down vote accepted

Available Keys

Look at man tmux, search / for KEY BINDINGS:

tmux allows a command to be bound to most keys, with or without a prefix key.

When specifying keys, most represent themselves (for example ‘A’ to ‘Z’). Ctrl keys may be prefixed with ‘C-’ or ‘^’, and Alt (meta) with ‘M-’.

In addition, the following special key names are accepted:

Up, Down, Left, Right, BSpace, BTab, DC (Delete), End, Enter, Escape, F1 to F20, Home, IC (Insert), NPage/PageDown/PgDn, PPage/PageUp/PgUp, Space, and Tab. Note that to bind the ‘"’ or ‘'’ keys, quotation marks are necessary [...]

M-S-Left should be Alt+Shift+Left for example.

List all bound keys

To list all key bindings, simply press Ctrl-b then ? while in a tmux session.

This is also documented in man tmux in section EXAMPLES:

Typing ‘C-b ?’ lists the current key bindings in the current window; up and down may be used to navigate the list or ‘q’ to exit from it.

You can also list all key-bindings via tmux list-keys. If you want to check for already set keys, you can grep it's output to check, if it's already set.


To find more via Google, search for Section names in man tmux - just type in tmux default key bindings for example :). But often man tmux is sufficient.

This site is a very good documentation about tmux and pops up, if you search for said string in Google.

Arch wiki is always good, too.

share|improve this answer
how does one actually use alt for MAC computers? I guess its different from the option key. – Charlie Parker Jan 28 at 22:19

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