(setq mm-default-directory (file-name-directory file))
(and (or (not (file-exists-p file))
(yes-or-no-p (format "File %s already exists; overwrite? "
(setq mm-default-directory (file-name-directory file))
(and (or (not (file-exists-p file))
(yes-or-no-p (format "File %s already exists; overwrite? "