iswitchb-mode
iswitchb-mode is an interactive autoloaded compiled Lisp function in `iswitchb.el
'.
(iswitchb-mode &optional ARG)
This function is obsolete since 24.4;
use `icomplete-mode' or `ido-mode' instead.
Toggle Iswitchb mode.
With a prefix argument ARG, enable Iswitchb mode if ARG is
positive, and disable it otherwise. If called from Lisp, enable
the mode if ARG is omitted or nil.
Iswitchb mode is a global minor mode that enables switching
between buffers using substrings. See `iswitchb' for details.