Variable: mode-line-buffer-identification
mode-line-buffer-identification is a buffer-local variable defined in
bindings.el.gz.
Documentation
Mode line construct for identifying the buffer being displayed.
Its default value is ("%12b") with some text properties added.
Major modes that edit things other than ordinary files may change this
(e.g. Info, Dired,...)
Probably introduced at or before Emacs version 18.
Source Code
;; Defined in /usr/src/emacs/lisp/bindings.el.gz
(defvar-local mode-line-buffer-identification
(propertized-buffer-identification "%12b")
"Mode line construct for identifying the buffer being displayed.
Its default value is (\"%12b\") with some text properties added.
Major modes that edit things other than ordinary files may change this
\(e.g. Info, Dired,...)")