Sharing clipboard between Emacs and OS X without invoking a shell

gistfile1.el

(defun paste-to-osx (text &optional push)
  (let ((process-connection-type nil))
    (let ((proc (start-process "pbcopy" "*Messages*" "pbcopy")))
      (process-send-string proc text)
      (process-send-eof proc))))
(defun copy-from-osx ()
  (let ((buf (get-buffer-create "*pbpaste*")))
    (with-current-buffer buf
      (erase-buffer)
      (call-process "pbpaste" nil "*pbpaste*")
      (buffer-string))))
(setq interprogram-cut-function 'paste-to-osx)
(setq interprogram-paste-function 'copy-from-osx)