Dired からファイルを Mac の quicklook or openコマンド で開く

dired-open-mac.el

(defun open-mac (path)
  (start-process "dired-open-mac" nil "open" path))

(defun quicklook-file (path)
  (interactive)
  (defvar cur nil)
  (defvar old nil)
  (setq old cur)
  (setq cur (start-process "ql-file" nil "qlmanage" "-p" path))
  (when old (delete-process old)))

(defun my-dired-open ()
  (interactive)
  (let ((exts-ql   '("jpeg" "jpg" "png" "gif"))
        (exts-open '("avi" "mkv" "mp4" "pdf")))
     (cond ((file-accessible-directory-p (dired-get-file-for-visit))
            (call-interactively 'dired-find-alternate-file))
           ((member (downcase (file-name-extension (dired-get-file-for-visit))) exts-ql)
            (funcall 'quicklook-file (dired-get-file-for-visit)))
           ((member (downcase (file-name-extension (dired-get-file-for-visit))) exts-open)
            (funcall 'open-mac (dired-get-file-for-visit)))
           (t
            (call-interactively 'dired-find-file-other-window)))))

(add-hook 'dired-mode-hook
          '(lambda ()
             (define-key dired-mode-map "\C-m"  'my-dired-open)))