preinst is in ipheth-utils 1.0+git20111206-0ubuntu4.
This file is a maintainer script. It is executed when installing (*inst) or removing (*rm) the package.
The actual contents of the file can be viewed below.
1 2 3 4 5 6 | #!/bin/sh
set -e
if [ -L /usr/share/doc/ipheth-utils ]; then
rm /usr/share/doc/ipheth-utils
fi
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