Variable: executable-insert
executable-insert is a customizable variable defined in
executable.el.gz.
Value
t
Documentation
Non-nil means offer to add a magic number to a file.
This takes effect when you switch to certain major modes,
including Shell-script mode (sh-mode).
When you type M-x executable-set-magic (executable-set-magic), it always offers to add or
update the magic number.
Source Code
;; Defined in /usr/src/emacs/lisp/progmodes/executable.el.gz
(defcustom executable-insert t
"Non-nil means offer to add a magic number to a file.
This takes effect when you switch to certain major modes,
including Shell-script mode (`sh-mode').
When you type \\[executable-set-magic], it always offers to add or
update the magic number."
:type 'boolean)