Variable: tab-line-mode-hook
tab-line-mode-hook is a customizable variable defined in
tab-line.el.gz.
Value
(tab-line-mode-set-explicitly(var)/tab-line-mode-set-explicitly(fun))
Documentation
Hook run after entering or leaving tab-line-mode(var)/tab-line-mode(fun).
No problems result if this variable is not bound.
add-hook automatically binds it. (This is true for all hook variables.)
Source Code
;; Defined in /usr/src/emacs/lisp/tab-line.el.gz
;;;###autoload
(define-minor-mode tab-line-mode
"Toggle display of tab line in the windows displaying the current buffer."
:lighter nil
(setq tab-line-format (when tab-line-mode '(:eval (tab-line-format)))))