Hi Vladimir,
Thanks for everything, it seems to work !
You are the only one who knew how to solve the problem.
Here is the content of my ~./emacs file that you probably need to improve :

-------------------------------- 8<
---------------------------------------------------------------------------------------------------------

(eval-after-load "context"
  '(setq TeX-command-list
     (cons '("ConTeXt"
"PATH=/home/aragorn/context/tex/texmf-linux-64/bin:$PATH context %s"
       TeX-run-command nil t :help "Run context (MarkIV)")
TeX-command-list))
)

(setq ConTeXt-mode-hook
      (lambda () (setq TeX-command-extra-options "--purgeall")))


(add-hook 'ConTeXt-mode-hook
          (lambda()
            (setq TeX-command-default "ConTeXt Full")))


-------------------------------- 8<
------------------------------------------------------------------------------------------------------

By cons if I add this :

-------------------------------- 8<
-----------------------------------------------------------------------------------------------------

(setenv "TEXMFCNF" nil)
(setenv "TEXROOT" "/home/aragorn/context/tex")
(setenv "TEXMFCACHE" (format "%s/.cache" (getenv "HOME")))


-------------------------------- 8<
---------------------------------------------------------------------------------------------------


 the compilation returns a damaged pdf file that I can not open.

I installed texlive 2018 and context standalone in my home directory and
emacs in the /usr/share/emacs directory with Arch Linux ; can that explain
my problems ?

Fabrice


Le ven. 24 août 2018 à 04:21, Vladimir Lomov <lomov.vl@yandex.ru> a écrit :

> Hello,
> ** Fabrice Couvreur [2018-08-23 10:48:42 +0200]:
>
> > Hi,
> > Thanks for your help but ...
>
> I checked again and it is fine. May be I was too unspecific. First, I
> changed a bit your example to this one:
>
> [test.tex]
> -------------------------------- 8< ------------------------------------
> \setupsynctex[state=start]
>
> \startusableMPgraphic{NumberHead}
>   draw outlinetext.f
>   ("\bf\namedheadnumber{chapter}")
>   (withcolor "lightgray")
>   ysized 50pt ;
> \stopusableMPgraphic
>
> \unexpanded\def\processMPheadnumber#1%
>   {\useMPgraphic{NumberHead}}
>
> \setuphead%
> [chapter]%
> [command=\HeadTitle,%
>  headstyle=\ss,%
>  numbercommand=\processMPheadnumber]
>
> \unexpanded\def\HeadTitle#1#2%
> {\framed%
>   [frame=off,%
>     bottomframe=on,%
>     width=broad,
>     align={broad,nothyphenated,left}]%
> {#1\blank[nowhite]#2}}
>
> \starttext
> \startchapter[title=First chapter]
>   \input ward
> \stopchapter
> \stoptext
>
> %%% Local Variables:
> %%% mode: context
> %%% TeX-master: t
> %%% End:
> -------------------------------- 8< ------------------------------------
>
> And second, I tweaked a bit my Emacs configuration:
>
> -------------------------------- 8< ------------------------------------
> (setenv "TEXMFCNF" nil)
> (setenv "TEXROOT" "/usr/local/opt/context/tex")
> (setenv "TEXMFCACHE" (format "%s/.cache" (getenv "HOME")))
> -------------------------------- 8< ------------------------------------
>
> (I have to do that because I have both TeX Live and ConTeXt
> Standalone/Suite in parallel, and use mainly LaTeX.)
>
> You should check your Emacs configuration.
>
> This is my Emacs configuration:
> https://bitbucket.org/vp1981/scripts/src/master/config/emacs/
> and I have
> Emacs:  27.0.50 (git)
> AUCTEX: 12.1 (git)
>
> [...]
>
> ---
> WBR, Vladimir Lomov
>
> --
> Come, you spirits
> That tend on mortal thoughts, unsex me here,
> And fill me, from the crown to the toe, top-full
> Of direst cruelty! make thick my blood,
> Stop up the access and passage to remorse
> That no compunctious visiting of nature
> Shake my fell purpose, not keep peace between
> The effect and it! Come to my woman's breasts,
> And take my milk for gall, you murdering ministers,
> Wherever in your sightless substances
> You wait on nature's mischief! Come, thick night,
> And pall the in the dunnest smoke of hell,
> That my keen knife see not the wound it makes,
> Nor heaven peep through the blanket of the dark,
> To cry `Hold, hold!'
>                 -- Lady MacBeth
>
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