postinst is in ubuntume-gdm-themes 1.4.
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 24 25 26 27 28 29 30 31 | #!/bin/sh
# postinst script for sabily-gdm-themes
set -e
case "$1" in
    configure)
      # If upgrading from 1.2 or less, then:
      # * Update the link of gdm-config-derivative if our theme was the 
      #   default gdm-config-derivative.
      # * remove /usr/share/ubuntume-gdm-themes/gdm-cdd.conf alternative.
      if [ ! -z $2 ] && [ "$2" \< "1.3" ] ; then
        if update-alternatives --display gdm-config-derivative | grep "link currently points to /usr/share/ubuntume-gdm-themes/gdm-cdd.conf" > /dev/null 2>&1 ; then
          update-alternatives --set gdm-config-derivative /usr/share/sabily-gdm-themes/gdm-cdd.conf
        fi
        update-alternatives --remove gdm-config-derivative /usr/share/ubuntume-gdm-themes/gdm-cdd.conf
      fi
    ;;
    abort-upgrade|abort-remove|abort-deconfigure)
    ;;
    *)
        echo "postinst called with unknown argument \`$1'" >&2
        exit 1
    ;;
esac
exit 0
 |