Variable: dired-click-to-select-map
dired-click-to-select-map is a variable defined in dired.el.gz.
Value
<mouse-2> dired-mark-for-click
Documentation
Keymap placed on files under dired-click-to-select mode.
Source Code
;; Defined in /usr/src/emacs/lisp/dired.el.gz
;;; Click-To-Select mode
(defvar-keymap dired-click-to-select-map
:doc "Keymap placed on files under `dired-click-to-select' mode."
"<mouse-2>" #'dired-mark-for-click)