Hello,
Before considering modifications, here's what I get when I do which context
:

Setting "/home/aragorn/context/tex" as ConTeXt root.
[aragorn@fab ~]$ which context
/home/aragorn/context/tex/texmf-linux-64/bin/context
[aragorn@fab ~]$

$ pacman -Qs texlive
>

 [root@fab aragorn]# pacman -Qs texlive
[root@fab aragorn]#

$ pacman -Qs emacs
>

 [root@fab aragorn]# pacman -Qs emacs
local/emacs 26.1-2
    The extensible, customizable, self-documenting real-time display editor
local/emacs-python-mode 6.2.3-1
    Python mode for Emacs
[root@fab aragorn]#

you mentioned that commands run in terminal worked fine, but you
>   invoked them by full path;
>


To be able to test with the
texlive context binary and context standalone context binary
.


The next in the next message after restarting my PC ...

Fabrice


Le mer. 29 août 2018 à 04:58, Vladimir Lomov <lomov.vl@yandex.ru> a écrit :

> Hello,
> ** Fabrice Couvreur [2018-08-28 11:18:58 +0200]:
>
> > Hi Vladimir,
>
> > I do not use Arch Linux repositories to install  texlive 2018 packages
>
> Some texlive-* packages could be installed as dependencies of other
> packages. You may check if your system has any texlive package:
>
>   $ pacman -Qs texlive
>
> > but I installed texlive 2018 "scheme-full" with tlmgr -gui  in
> > /home/aragorn /texlive/2018.  I then make regular updates in the same
> > way. No texlive traces in the \usr\share\ directory or elsewhere.
>
> I prefer to rely on package manager.
>
> > Standalone Context is also installed in my home directory. However,
> > Emacs is installed from the Arch Linux repositories and is located in
> > /usr/share/emacs.
>
>   $ pacman -Qs emacs
>
> > So I have to add the path of texlive 2018 ?
> > Maybe you do not need to add the Context Standalone path ?
> > My ~/.profile file would be this :
> >
> > source /home/aragorn/context/tex/setuptex
> > export PATH = $ PATH: /home/aragorn/texlive/2018/bin/x86_64-linux
> > export PATH = $ PATH: /home/aragorn /bin
>
> This part is a bit strange:
> - in message
>   https://mailman.ntg.nl/pipermail/ntg-context/2018/092418.html
>   you mentioned that commands run in terminal worked fine, but you
>   invoked them by full path;
>
> - in the same message you set PATH in emacs as
>
>     (setenv "PATH" "/home/aragorn/context/tex/texmf-linux-64/bin/:$PATH" t)
>
>   (I have to admit that I didn't know it is possible to use '$PATH' in
>   setenv), so it prepends path to context binary to PATH list. The above
>   lines do opposite: they append path to context binary to the end of
>   PATH list.
>
>   The first line, 'source ...', helps here because 'setuptex' in turns
>   prepend path to context binary to PATH.
>
> When you invoke 'context' in terminal (I assume it is bash shell) the
> shell searches program in current directory (depends on configuration)
> and then in PATH, the first wins. So to use context from ConTeXt
> standalone you may simply do
>
>   $ export PATH=$HOME/context/tex/texmf-linux-64/bin:$PATH
>
> either in terminal or in ~/.profile. You may always check if this is
> true by runnig
>
>   $ command -v context
>
> (for bash shell) or
>
>   $ which context
>
> Returning to your problem. I looked closely again in messages with
> output from context and I don't understand what may cause the error.
> Seems that Emacs uses correct context (according to loading files).
> Could you show in full your ~/.emacs file? Do you use AUCTeX or bare
> Emacs?
>
> > Regards,
> > Fabrice
> >
>
> [...]
>
> ---
> WBR, Vladimir Lomov
>
>
> --
> Uncontrolled power will turn even saints into savages.  And we can all
> be counted on to live down to our lowest impulses.
>                 -- Parmen, "Plato's Stepchildren", stardate 5784.3
>
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