/usr/bin/showglyphs is in texlive-font-utils 2009-10ubuntu1.
This file is owned by root:root, with mode 0o777.
It is a symlink to /usr/bin/../share/texmf-texlive/scripts/fontools/showglyphs
/usr/bin/../share/texmf-texlive/scripts/fontools/showglyphs