command run in docker-tramp running on the host rather than remote

Question

The setup:

I have a docker container connected with a mounted volume containing an org file. The docker container has both texlive and emacs (configured exactly the way it is on my host) installed. I can open the org file and run org-latex-preview on the math components without any problems.

The problem:

I recently installed docker-tramp and figured I wouldn't need a separate installation of emacs in my docker containers. However, when I opened the same org file and ran org-latex-preview I got the following message in the *Org Preview LaTeX Output* buffer:

This is pdfTeX, Version 3.14159265-2.6-1.40.20 (TeX Live 2019/Debian) (preloaded format=latex)
 restricted \write18 enabled.
entering extended mode
! I can't find file `/tmp/orgtextfP6YZ.tex'.
<*> /tmp/orgtextfP6YZ.tex
                         
(Press Enter to retry, or Control-D to exit)
Please type another input file name
! Emergency stop.
<*> /tmp/orgtextfP6YZ.tex
                         
No pages of output.
Transcript written on /tmp//texput.log

Now the orgtextfP6YZ.tex file is not in the docker container's /tmp folder; however, it has been generated in the host's /tmp folder. So the command that org-latex-preview uses (dvipng) accesses the host's /tmp folder, which means that dvipng was run on the host rather than the remote (docker container).

When I'm using a buffer I accessed through docker-tramp, any command I call using M-! runs in the remote. So how do I configure it (or TRAMP in general) so that commands used indirectly (called by a function in emacs) are also run in the remote?

Answer 1

See the function org--latex-preview-region. There's the comment

;; Emacs cannot overlay images from remote hosts.  Create it in
;; `temporary-file-directory' instead.

Running on a remote host is disabled by intention.

OTOH, everything you start with M-! (or M-&) is given to a shell, which can run also remotely.