is a variable defined in `
Its value is
Non-nil means Dired should pass the "--dired" option to "ls".
The special value of `unspecified' means to check explicitly, and
save the result in this variable. This is performed the first
time `dired-insert-directory' is called.
Note that if you set this option to nil, either through choice or
because your "ls" program does not support "--dired", Dired
will fail to parse some "unusual" file names, e.g. those with leading
spaces. You might want to install ls from GNU Coreutils, which does
support this option. Alternatively, you might want to use Emacs's
own emulation of "ls", by using:
(setq ls-lisp-use-insert-directory-program nil)
This is used by default on MS Windows, which does not have an "ls" program.
Note that `ls-lisp' does not support as many options as GNU ls, though.
For more details, see Info node `(emacs)ls in Lisp'.
You can customize this variable.