preinst is in libfbclient2 2.5.3.26778.ds4-5+deb8u1.
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 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 | #!/bin/sh
set -e
case "$1" in
install|upgrade)
# dpkg does not replace directories by symlinks or vice versa.
TARGET="firebird${FB_VER}-common-doc"
D="/usr/share/doc/libfbclient2"
if [ ! -L "$D" -a -d "$D" ]; then
echo "Found legacy directory $D which needs to be replaced by a symlink to $TARGET"
if rmdir "$D" >/dev/null 2>&1 ; then
echo "Directory is empty, removed"
else
echo "Directory not empty, moving to libfbclient2.dpkg-old"
mv --backup=existing "$D" "$D.dpkg-old"
fi
fi
;;
esac
exit 0
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