for dired-compare-directories.
(define-key map [menu-bar immediate dashes]
'("--"))
+ (define-key map [menu-bar immediate compare-directories]
+ '(menu-item "Compare directories" dired-compare-directories
+ :help "Mark files with different attributes in two dired buffers"))
(define-key map [menu-bar immediate backup-diff]
'(menu-item "Compare with Backup" dired-backup-diff
:help "Diff file at cursor with its latest backup"))