Tmux is terminal multiplexer. Kinda like old screen, but with much more functionality.

When I work on my servers, it's pretty common that I have to do the same things to multiple servers. To make my life easier I start tmux, and in there start many “windows", each related to work on single server.

I name the windows in a way that let's me quickly find them, without false positives.

For example, if I'd have to upgrade servers db1..db5 then I'd create windows “up-db1" .. “up-db5", and each window would work on single server.

This is already scriptable – let's assume I'd want to show uptime in all of the windows, I can:

tmux lsw -F '#W' | grep -E '^up-db[0-9]+$' | xargs -r -d$'\n' -I% tmux send-keys -t % uptime Enter

But this gets tedious fast.

So I wrote tmux_send_to_many script.

Thanks to it, I can rewrite the pipeline above into simpler:

tmux_send_to_many '^up-db[0-9]+$' uptime Enter

It has options to debug, list panes/windows that would get the keys, or even to send keys to different sessions.

Full help:

=$ tmux_send_to_many -h
Syntax:
    /home/depesz/bin/tmux_send_to_many [-a] [-l] [-v] PANE_MATCHER LIST OF STRINGS

Options:
    -a : Enables matching across all sessions, not only current.
    -l : List all matching panes and exit, don't send any keys.
    -v : Print verbose information while working.

Arguments:
    PANE_MATCHER    : Regular expression (compatible with egrep), that will be
                      used to select panes that should be processed.  Without
                      -a, panes are listed only from current session, and have
                      format:
                      WINDOW_NAME.PANE_INDEX
                      With -a, panes are listed from all sessions, and have
                      format:
                      SESSION_NAME:WINDOW_NAME.PANE_INDEX
    LIST OF STRINGS : What should be sent to all selected panes.

If you're interested, it's licensed under 3 clause BSD license.