call graphviz compile on a file, and display the image when the compile is complete

my-graphviz-mode-hook.el

;(load-file "~/.elisp/graphviz-dot-mode.el")

; http://users.skynet.be/ppareit/projects/graphviz-dot-mode/graphviz-dot-mode.html
; graphviz-dot-mode.el

;;;;
;;;; dot-compile in background
;;;;


(defun my-graphviz-dot-compile-sentinel (process change)
  "Sentinel to display dot file.
PROCESS is the dot compile process
CHANGE is ignored."
  (when (eq (process-status process) 'exit)
    (let* (
           (buf (process-buffer process))
           (name (process-name process))
           )
      (message (concat name "FINISHED"))
      (with-current-buffer (buffer-local-value 'original-buffer buf) (graphviz-dot-preview))
      )
    )
  )

(defun my-graphviz-dot-compile ()
  (interactive)
  (let* (
         (my-shortname (file-name-sans-extension buffer-file-name))
         (my-imagefilename (concat my-shortname "." graphviz-dot-preview-extension))
         (my-process-name (concat "*dot-compile*" my-shortname "*"))
         (original-buffer (current-buffer))
         )
    (if (buffer-modified-p)
        (save-buffer))
    (message (concat my-process-name " Started"))
    ;; launch dot compile process
    (setq my-process
          (start-process my-process-name my-process-name
                         graphviz-dot-dot-program
                         (concat "-T" graphviz-dot-preview-extension)
                         buffer-file-name
                         (concat "-o" my-imagefilename)
                         ))
    ;; make sure the process-buffer knows who launched it
    (with-current-buffer (process-buffer my-process)
      (set (make-local-variable 'original-buffer) original-buffer)
      )
    ;; when there is a change in the processes status, run my sentinel
    (set-process-sentinel my-process 'my-graphviz-dot-compile-sentinel)
    )
  )

;graphviz-dot-mode-hook

(defun my-graphviz-mode-hook ()
  ;(add-hook 'after-save-hook 'my-graphviz-dot-compile t t)
  (define-key graphviz-dot-mode-map
    [(control c)(control p)] 'my-graphviz-dot-compile)
)

(setq graphviz-dot-mode-hook 'my-graphviz-mode-hook)