slackware-current/source/n/vsftpd/doinst.sh

config() {
  NEW="$1"
  OLD="$(dirname $NEW)/$(basename $NEW .new)"
  # If there's no config file by that name, mv it over:
  if [ ! -r $OLD ]; then
    mv $NEW $OLD
  elif [ "$(cat $OLD | md5sum)" = "$(cat $NEW | md5sum)" ]; then # toss the redundant copy
    rm $NEW
  fi
  # Otherwise, we leave the .new copy for the admin to consider...
}
if [ -r etc/pam.d/vsftpd.new ]; then
  config etc/pam.d/vsftpd.new
fi
config etc/vsftpd.conf.new
config etc/logrotate.d/vsftpd.new
rm -f etc/logrotate.d/vsftpd.new