postinst is in gstreamer1.0-packagekit 0.8.17-4ubuntu6~gcc5.4ubuntu1.
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 | #!/bin/sh
# postinst script for gstreamer1.0-packagekit
set -e
update-alternatives --install /usr/bin/gstreamer-codec-install \
gstreamer-codec-install \
/usr/lib/packagekit/pk-gstreamer-install 80 || true
exit 0
|