tmux how many windows in current session

Question

In a bash script, I want to get the count of windows in current tmux session.

I found tmux display-message -p '#I' get count of pane in current window. But how can I get count of windows instead?

Answer 1

#I is not the number of panes in the window, it is the pane index - for number of panes you want '#{window_panes}'.

Similarly, for number of windows in a session you can do '#{session_windows}'.