This is probably simple, but I really can't find out how you do it. I have read the man pages and googled without results.

Problem: How do I run a command in a detached tmux window?

Example: I want my detached window 'foo' to run 'ls', but I want to do it from another terminal.

I've tried stuff like: 'tmux -t foo ls' without results.

1 Answer 1


The command is send. send is a key sequence, so treat it accordingly (e.g. you'll probably want ENTER). The target is specified with -t. You may want foo.0 or foo.1 depending on the pane you wish to hit.

tmux send -t foo.0 ls ENTER

send is short for send-keys, which is located in the man pages, but perhaps a bit difficult to find in that mile of text.

  • Great answer. Very informative and works a charm. Thanks!
    – Accatyyc
    Dec 10, 2011 at 15:10
  • The most majestic solution for this issue! Massive thanks!
    – 3bdalla
    Feb 15, 2017 at 6:21
  • 4
    Note that to target a specific window in a specific session, you separate them with a colon => tmux send-keys -t foosession:foo.0 ls ENTER
    – nickspoon
    Mar 17, 2017 at 1:16
  • 3
    If you want to send spaces between words, you should surround the command with two apostrophes. The ENTER command should still be outside. This works for me on UBUNTU 16.04: tmux send -t session_name 'echo durp' ENTER Mar 21, 2018 at 16:40

You must log in to answer this question.

Not the answer you're looking for? Browse other questions tagged .