If I compare /usr/share/texmf-dist/web2c/texmfconf.lua with its counterpart in Arch Linux, I found the differences in the following entries:

Gentoo:
TEXMFSYSVAR     = "selfautoparent:texmf-var",
TEXMFOS         = "selfautodir:",
TEXMFDIST       = "selfautoparent:texmf-dist",
TEXMFSYSCONFIG  = "selfautoparent:texmf-config",

Arch:
TEXMFSYSVAR     = "/var/lib/texmf",
TEXMFOS         = "selfautodir:share",
TEXMFDIST       = "selfautodir:share/texmf-dist",
TEXMFSYSCONFIG  = "/etc/texmf",
 
Changing the Gentoo file to its Arch equivalent fixes the issue after running "mtxrun --generate". There may actually be a reason why this configuration is different in Gentoo compared to Arch, but I haven't had the time yet to look into it further.

On Sat, 5 Sep 2020 at 13:27, <mylists@posteo.de> wrote:
Hi,

this is my first post to this mailinglist. I am no native speaker...
if something sound somehow ... I will try to give my best.... ;)


I am using GENTOO Linux, which compiles everything on the target
instead of pulling ready compiled, binary packages into the system.

I did a fresh install of Texlive 2020 via the package-manager
"emerge". On Gentoo this is handled via a "virtual package", which
can be configured beforehand to include or exclude certain parts.

I choose to get the HUGE package (incluing LaTeX, ConTeXt, plainTeX
and others).

After the installation I tried to typeset examples of a LaTeX- and
a plain TeX document, which works out of the box.

Then I tried a ConTeXt document and it fails:

    context somefile.tex

gave me:

mtxrun          | unknown script 'context.lua' or 'mtx-context.lua'

.

While searching the internet I found, that one has to run

mtxrun --generate

in advance.

Doing so mtxrun starts to index my whole harddisk starting with
my $HOME, from which I started it.

It reports A LOT of "confusing file"s....

I searched the installed TeXlive installation for context.lua
and mtx-context.lua -- they were installed and not "totally" missing.

So I tried/guessed to run

mtxrun --generate /usr/share/texmf-dist /usr/share/texlive-site

and the file under $HOME were no longer indexed.

context somefile.tex

gave me the above mentioned error still, though.

It "feels" like context does not respect setting made via
the configuration settings under /etc/texmf...

So I "hacked" (really, it was a crude hack/idea...nothing
more) TEXMF and inserted

export TEXMF=/usr/share/texmf-dist:/usr/share/texlive-site

into my shells RC-file, restarted the shell and

now

context somefile.tex

"worked"...:

Each time it seems to re-index parts of ???, reports a lot
of "confusing file"s but creates a valid looking pdf.

I think, the package setup provided by GENTOO has a problem
I want to help to fix that...but I have no clue, what the
real culprit is here...

Setting TEXMF this way feels like a random and accidentally
working hack and I already feel the next problem raising up
at the horizon...

Some additional problems:

tlmgr does not work

mtxrun partially does not find its own modules

mtxrun --variables

lists a LOT of unset environment variables

...

It looks like some basic and fundamental "initial" environment
variable is missing.

But I need a knowledgeable guru before I am able to get nearer
to the root of the culprit.

Thank you very much in advance for any help offered!

\cheers
Meino
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