/usr/share/doc/texlive-doc/fonts/fontinst/examples/mathptmx/unsetmu.mtx is in texlive-font-utils 2013.20140215-2.
This file is owned by root:root, with mode 0o644.
The actual contents of the file can be viewed below.
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\metrics
\unsetglyph{mu}
\endmetrics
|