Hello,
** Fabrice Couvreur [2018-08-24 12:31:19 +0200]:

> 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")))

Why did you set "ConTeXt Full" as your default command? The above
'setq' introduces "ConTeXt" command to process a context file. When I
said that everything is OK I meant that I did C-c C-c, checked that in
minibuffer the "ConTeXt" command is chosen and then hit Enter.

> -------------------------------- 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 don't know why you get "damaged" pdf file (in fact how do you know
that file is damaged?) but "TEXMFCNF" is special variable that I uses to
tweak TeX Live configuration for my latex workflow but context
(standalone and from TL) refuses to work if this variable is set (in
terminal I do 'unset' while in Emacs I set its value to 'nil' because
this is identical to "unset" it). The "TEXROOT" variable I found in
update script, I'm not sure if context requires it to work but IMHO, it
is harmless. And the last variable "TEXMFCACHE" I use to force context
to use ~/.cache for "luatex-cache" directory and not "pollute" my home
directory (without it the "luatex-cache" directory will be created in
$HOME directory).

> 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 ?

Not sure but I'll wait you answer about "ConTeXt Full" vs "ConTeXt" I
mentioned above.

> Fabrice

[...]

---
WBR, Vladimir Lomov

-- 
I'm serious about thinking through all the possibilities before we
settle on anything.  All things have the advantages of their
disadvantages, and vice versa.
             -- Larry Wall in <199709032332.QAA21669@wall.org>