postinst is in libapache2-mod-passenger 4.0.37-2.
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 | #!/bin/sh
set -e
# Automatically added by dh_apache2
if true; then
	if [ -e /usr/share/apache2/apache2-maintscript-helper ] ; then
		. /usr/share/apache2/apache2-maintscript-helper
		for conf in passenger  ; do
			apache2_invoke enmod $conf  || exit $?
		done
	fi
fi
# End automatically added section
 |