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%%EOF

documentclass{minimal}
usepackage{graphicx}
newboxfigbox
begin{document}
setboxfigboxhbox{includegraphics{test.eps}}%
thehtfigbox

fboxsep0pt
fbox{unhboxfigbox}
end{document}

This is pdfTeX, Version 3.14159265-2.6-1.40.18 (TeX Live 2017) (preloaded format=latex)