How to send a command to all panes in tmux?

A bit late to the party but I didn't want to set and unset synchronize-panes just to send one command so I created a wrapper function around tmux and added a custom function called send-keys-all-panes.

_tmux_send_keys_all_panes_ () {
  for _pane in $(tmux list-panes -F '#P'); do
    tmux send-keys -t ${_pane} "$@"
  done
}

I also create a wrapper around the tmux command to simplify calling this function (for convenience). The wrapper and the above code are all here.

This allows me to run tmux send-keys-all-panes <command> or tmux skap <command to send <command> to all panes.

Note that tmux is aliased to my wrapper function tmux_pp.

Have you tried following in tmux window with multiple panes

Ctrl-B :

setw synchronize-panes on

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