/usr/share/texmf-texlive/tex/plain/plgraph/color.tex is in texlive-plain-extra 2009-10ubuntu1.
This file is owned by root:root, with mode 0o644.
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1 2 3 4 5 6 7 8 9 | % Plain TeX interface to color package.
% David Carlisle
\input miniltx
\makeatletter
\def\Gin@driver{dvips.def}
\input color.sty
\resetatcatcode
|