How to keep terminal window title in sync with tmux window

fishitermterminaltmux

I am using a program called "Timing" to track my time. Timing uses the name of the current window in iTerm for categorization purposes.

I'd like to set the current title of iTerm to match the name of the currently active tmux window.

I've set up a file at ~/.config/fish/functions/fish_title.fish with:

function fish_title
  tmux display-message -p '#W'
end

This successfully outputs the current Tmux window title to the terminal window whenever I open a new terminal window. However, if I rename a tmux window, or switch to a new window, the terminal does not update.

It does update if I use something like pwd in fish_title:

function fish_title
  pwd
end

Any ideas on how to make fish_title grab the tmux window name dynamically?

Best Answer

First thing to point out is that you can do this via tmux completely independent of your shell. Add the following to your ~/.tmux.conf; for example:

set-option -g set-titles on
set-option -g set-titles-string "#S / #W"

Also, you need to ensure iTerm2 is configured to let programs set the title via an escape sequence. See the "Terminal may set tab/window title" section in https://www.iterm2.com/documentation-one-page.html.

But your real problem is that the escape sequence sent by the fish_title function isn't passed through by tmux. Tmux instead uses the value to set the pane title. This is explained, albeit not clearly, in the "NAMES AND TITLES" section of man tmux. Add #T to the set-titles-string to see that it is in fact, being set to the same value as the window name via your fish_title function.

Related Solutions

Tmux: sharing current window title (#T) from within nested tmux sessions

I did some digging and found the answer for myself. Well, the way I have found to accomplish my gaol is not elegant, but it will work to get the job done.

First, you need to have the "set-titles" option turned on in your .tmux.conf file. As well as the appropriate title string:

set -g set-titles on
set -g set-titles-string '#T'

However, if you implement this, you will immediately notice that it doesn't work. The problem is that this only sends the title string up stream if it starts in an xterm variant (tmux/screen TERM variable is "screen*"). So, when starting a nested tmux session, you must fool the terminal by resetting the variable. The following example will keep the TERM suffix (e.g. "-256color").

TEMP_TERM=$TERM
TEMP_TERM_SUFFIX=${TERM#$(echo $TERM | cut -f 1 -d'-')}
TERM="xterm${TEMP_TERM_SUFFIX}"

I am not sure if it matters, but I think it is smart to reset TERM back after closing tmux (so save it into a temp variable). Using this, a simple shell script can be made to open a nested tmux session that sends the #T title variable upstream to it's parent sessions.

This all works, but is somewhat of a pain considering that work must be done to ensure infinite nesting loops aren't created in the event that we automatically start our shell up in tmux. If anyone has a better solution I would love to here it as well!

Let tmux set urxvt window title according to session-name

Try adding the following to your ~/.tmux.conf file.

# Turn on window titles
set -g set-titles on

# Set window title string
#  #H  Hostname of local host
#  #I  Current window index
#  #P  Current pane index
#  #S  Session name
#  #T  Current window title
#  #W  Current window name
#  #   A literal ‘#’
set -g set-titles-string '#S:#I.#P #W'

# Automatically set window title
setw -g automatic-rename

Best Answer

Related Solutions

Tmux: sharing current window title (#T) from within nested tmux sessions

Let tmux set urxvt window title according to session-name

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