% arara: xelatex: {shell: on}
\documentclass{article}

\usepackage{texosquery}
% Disable texosquery:
%\TeXOSQueryDryRuntrue 
\usepackage{datetime2}

% If you get an error that looks like:
% ! I can't find file `"|texosquery -n"'.
% Then the shell escape has been restricted and texosquery
% wasn't allowed to run.

\begin{document}
\DTMnow.

\DTMsavefilemoddate{moddate}{\jobname.tex}
File \texttt{\jobname.tex} last modified: \DTMuse{moddate}.

\end{document}
