ediff-revision

ediff-revision is an interactive autoloaded compiled Lisp function in `ediff.el'.

It is bound to <menu-bar> <tools> <compare> <ediff-revision>.

(ediff-revision &optional FILE STARTUP-HOOKS)

Run Ediff by comparing versions of a file.
The file is an optional FILE argument or the file entered at the prompt.
Default: the file visited by the current buffer.
Uses `vc.el' or `rcs.el' depending on `ediff-version-control-package'.