/usr/share/doc/texlive-doc/plain/graphics-pln/exmplcol.tex is in texlive-plain-extra 2014.20141024-1.
This file is owned by root:root, with mode 0o644.
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1 2 3 4 5 | \input color
a \textcolor{red}{bbb} \colorbox{green}{one two}
\bye
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