                  (y-or-n-p "Open more than 5 files? ") ) )
     (when doIt
       (cond
-       ((string-equal system-type "windows-nt")
+       ((ar/windowsp)
         (mapc (lambda (fPath) (w32-shell-execute "open" (replace-regexp-in-string "/" "\\" fPath t t)) ) myFileList))
-       ((string-equal system-type "darwin")
+       ((ar/osxp)
         (mapc (lambda (fPath) (shell-command (format "open \"%s\"" fPath)) )  myFileList) )
-       ((string-equal system-type "gnu/linux")
+       ((ar/gnulinuxp)
         (mapc (lambda (fPath) (let ((process-connection-type nil)) (start-process "" nil "xdg-open" fPath)) ) myFileList) ) ) ) ) )
 (global-set-key (kbd "C-M-o") 'xah-open-in-external-app)
 

(setq whitespace-line-column 100)
(setq whitespace-style '(face lines-tail))

;; New browser tab.
(cond
 ((string-equal system-type "darwin") ; Mac OS X
  (defun ar/new-browser-tab ()
    "Open a new browser tab in the default browser."
    (interactive)

  (use-package exec-path-from-shell
    :ensure exec-path-from-shell)
  (exec-path-from-shell-initialize))
 ((ar/gnulinuxp) ; Linux
  (defun ar/new-browser-tab ()
    "Open a new browser tab in the default browser."
    (interactive)
