Hello,
** Fabrice Couvreur [2018-08-29 11:39:07 +0200]:

> 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 ~]$

Ok, context from ConTeXt Standalone.

> $ pacman -Qs texlive

Ok, your system doesn't have any texlive packages.

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

Running commands as root is a bit dangerous.

> $ 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]#

Your system has only these two packages.

> 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
> .

Got it.

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

[..]

---
WBR, Vladimir Lomov

-- 
I think that I shall never see
A thing as lovely as a tree.
But as you see the trees have gone
They went this morning with the dawn.
A logging firm from out of town
Came and chopped the trees all down.
But I will trick those dirty skunks
And write a brand new poem called 'Trunks'.