[Tex/LaTex] Python cannot compile LaTeX file

Question

I am using a Conda Python installation and Jupyter to work with a script producing a LaTeX file I want to compile. These are the relevant code lines:

import subprocess
xelatex= "/usr/local/texlive/2018/bin/x86_64-darwin/xelatex"
subprocess.check_call([xelatex, '-shell-escape', '-file-line-error', '-interaction=nonstopmode', '-synctex=1', my_folder+'/output_file.tex'])

Unfortunately, the LaTeX source file does not get compiled and Python returns a non-zero exit status along the following lines:

---------------------------------------------------------------------------
CalledProcessError                        Traceback (most recent call last)
<ipython-input-26-fc4edbf90d41> in <module>
      1 import subprocess
      2 xelatex= "/usr/local/texlive/2018/bin/x86_64-darwin/xelatex"
----> 3 subprocess.check_call([xelatex, '-shell-escape', '-file-line-error', '-interaction=nonstopmode', '-synctex=1', dir_AED+'/registro_lezioni.tex'])

~/anaconda3/lib/python3.6/subprocess.py in check_call(*popenargs, **kwargs)
    289         if cmd is None:
    290             cmd = popenargs[0]
--> 291         raise CalledProcessError(retcode, cmd)
    292     return 0
    293 

CalledProcessError: Command '['/usr/local/texlive/2018/bin/x86_64-darwin/xelatex', '-shell-escape', '-file-line-error', '-interaction=nonstopmode', '-synctex=1', 'my_folder+'/output_file.tex']' returned non-zero exit status 1.

I have a Tex Live 2018 installation on my Mac that works smoothly with many other apps:

Last login: Sat Nov  3 07:39:44 on ttys000
Restored session: Sat Nov  3 07:33:30 CET 2018MacBook-Pro:~ m*****$ xelatex
This is XeTeX, Version 3.14159265-2.6-0.99999 (TeX Live 2018) (preloaded format=xelatex) restricted \write18 enabled.
**

Using any other LaTeX-based app, like Texpad, the source file gets compiled with no errors. I went to the Conda terminal window and the problem seems to be that the LaTeX compiler cannot find a ancillary file:

ABD: EveryShipout initializing macros
(/usr/local/texlive/2018/texmf-dist/tex/latex/translator/translator-basic-dicti
onary-English.dict)
(/usr/local/texlive/2018/texmf-dist/tex/latex/siunitx/siunitx-abbreviations.cfg
) (/usr/local/texlive/2018/texmf-dist/tex/latex/wasysym/uwasy.fd)

! LaTeX Error: File `fragment.tex' not found.

Nevertheless, the file fragment.tex does live in the same folder, but the LaTeX compiler cannot find it.

In sum, I need to instruct the LaTeX compiler to look for files in the same folder where the main source file is located.

Answer 1

tex relative paths are relative to the working directory from where the program was started, not the directory of the main file. can you get python to do

cd foo; xeletex file

instead of

xelatex foo/file

?