dired-omit-files-p

dired-omit-files-p is a variable defined in `dired-x.el'.
Its value is

nil

• Automatically becomes buffer-local when set.
• This variable is an alias for `dired-omit-mode'.
• This variable is obsolete since 22.1;
  use `dired-omit-mode' instead.

Documentation:
Non-nil if Dired-Omit mode is enabled.
Use the command `dired-omit-mode' to change this variable.