(defun my-cperl-hook ()
  "What to run when cperl-mode is turned on"
  ;; Function to call perltidy
  (defun perltidy-whole-buffer ()
    "Filter the current buffer through perltidy"
    (interactive)
    (shell-command-on-region
       (point-min) (point-max) "perltidy -st"
       nil 1 shell-command-default-error-buffer
    )
  )
  ;; Bind key

  (define-key cperl-mode-map [f6] 'perltidy-whole-buffer)
)

##</code><code>##

(custom-set-variables
  ;; custom-set-variables was added by Custom -- don't edit or cut/paste it!
  ;; Your init file should contain only one such instance.
  ;; ...
 '(cperl-mode-hook (quote (my-cperl-hook)))
)