Get screen resolution on Mac OSX

resolution_osx.el

(with-temp-buffer
  (shell-command
   "osascript -e 'tell application \"Finder\" to get bounds of window of desktop'" t)
  (goto-char (point-min))
  (if (re-search-forward "[0-9]+, [0-9]+, \\([0-9]+\\), \\([0-9]+\\)")
      (let ((width (buffer-substring-no-properties
                    (match-beginning 1) (match-end 1)))
            (height (buffer-substring-no-properties
                     (match-beginning 2) (match-end 2))))
        (mapcar #'string-to-int  (list width height)))))

resolution_xwindow.el

(when (executable-find "xdpyinfo")
  (with-temp-buffer
    (shell-command "xdpyinfo" t)
    (goto-char (point-min))
    (when (re-search-forward "dimensions:\s+\\([0-9]+\\)x\\([0-9]+\\)" nil t)
      (let ((width (buffer-substring-no-properties
                    (match-beginning 1) (match-end 1)))
            (height (buffer-substring-no-properties
                     (match-beginning 2) (match-end 2))))
        (mapcar #'string-to-int  (list width height))))))