Can't write accents in R graphics

["Sebastien Vauban" <sva-news-D0wtAvR13HarG/iDocfnWg@public.gmane.org>]

#+TITLE:     ECM Process Coding System
#+PROPERTY:  eval yes
#+PROPERTY:  exports both
#+PROPERTY:  cache no

* Problem

  I can't write accents in graphic titles (nor legends).

* Settings

  After Googling (a lot), I always come back to the same set of solutions:

  - Adding the following in my ~.emacs~ file:

    #+begin_src emacs-lisp
    (setq process-coding-system-alist '(("R.*" . utf-8-unix)))
    #+end_src

    #+begin_src emacs-lisp
    (add-hook 'ess-R-post-run-hook
              (lambda () (set-buffer-process-coding-system
                          'utf-8-unix 'utf-8-unix)))
    #+end_src

  - Setting the process coding system in the =*R*= buffer:

    #+begin_src emacs-lisp
    M-x set-buffer-process-coding-system RET utf-8-unix RET utf-8-unix RET
    #+end_src

  None of those does work for me, from an Org file...

* Example

** Text

   Print a string does always work, in the Org buffer, and in the export.

   #+begin_src R
   print("Élève")
   #+end_src

   #+results:
   : Élève

** Graph

   But adding a title with accents never does:

   #+header: :file ecm-R-coding-system.png
   #+begin_src R :results graphics :width 240 :height 240
   x <- 0:12
   plot(sin(x/2))
   title("Élève")
   #+end_src

   #+results:
   [[file:ecm-R-coding-system.png]]

* Observations

  You can see a demo of (some of) the tests I made on
  http://screencast.com/t/7Nz87zuqiz.

  Maybe the problem is not related neither to Org, nor ESS, as I see that
  =sessionInfo()= outputs French stuff.

Maybe some of the R users here could share their experience with the "coding
system" configuration?

Best regards,
  Seb

-- 
Sebastien Vauban