copy to clipboard from emacs in terminal

pbcopy.el

;; copy to clipboard from emacs in terminal
;; 
;; if you use emacs in tmux you should enable pbcopy in tmux first
;; http://superuser.com/questions/231130/unable-to-use-pbcopy-while-in-tmux-session

(defun pbcopy-region (start end)
  (interactive "r")
  (pbcopy (buffer-substring start end)))

(defun pbcopy (string)
  (shell-command (concat "echo "
                         (shell-quote-argument string)
                         " | pbcopy")))