postinst is in check-mk-server 1.2.8p16-1ubuntu0.1.
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 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 | #!/bin/bash
set -e
# Source debconf library.
. /usr/share/debconf/confmodule
db_stop
# a little helper for getting permissions right
setperm() {
    local user="$1"
    local group="$2"
    local mode="$3"
    local file="$4"
    shift 4
    # only do something when no setting exists
    if ! dpkg-statoverride --list "$file" >/dev/null 2>&1; then
      chown "$user":"$group" "$file"
      chmod "$mode" "$file"
    fi
}
case "$1" in
	  configure)
		#make sure our nagios user exists  
		if ! getent passwd nagios > /dev/null ; then
			echo 'Adding system-user for nagios' 1>&2
			adduser --system --group --home /var/lib/nagios \
			  --disabled-login --force-badname nagios > /dev/null
		fi
		#fix permissions for some directorys
		test -d /var/lib/check_mk/cache || mkdir -p /var/lib/check_mk/cache
		setperm nagios nagios 0750 /var/lib/check_mk/cache
		test -d /var/lib/check_mk/autochecks || mkdir -p /var/lib/check_mk/autochecks
		setperm nagios nagios 0750 /var/lib/check_mk/autochecks
		test -d /var/lib/check_mk/precompiled || mkdir -p /var/lib/check_mk/precompiled
		setperm nagios nagios 0750 /var/lib/check_mk/precompiled
		test -d /var/lib/check_mk/counters/ || mkdir -p /var/lib/check_mk/counters/
		setperm nagios nagios 0750 /var/lib/check_mk/counters/
		test -d /var/lib/check_mk/logwatch/ || mkdir -p /var/lib/check_mk/logwatch/
		setperm nagios www-data 0770 /var/lib/check_mk/logwatch/
		test -d /var/lib/check_mk/notify/ || mkdir -p /var/lib/check_mk/notify/ 
		setperm nagios www-data 0770 /var/lib/check_mk/notify/
    ;;
  abort-upgrade|abort-remove|abort-deconfigure)
    ;;
  *)
    echo "postinst called with unknown argument \$1'" >&2
    exit 1
    ;;
esac
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