Replacement /etc/init.d/hostname.sh to provide for auto changing hosts hostname

hostname.sh

#! /bin/sh
### BEGIN INIT INFO
# Provides:          hostname
# Required-Start:
# Required-Stop:
# Should-Start:      glibc
# Default-Start:     S
# Default-Stop:
# Short-Description: Set hostname based on /etc/hostname
# Description:       Read the machines hostname from /etc/hostname, and
#                    update the kernel value with this value.  If
#                    /etc/hostname is empty, the current kernel value
#                    for hostname is used.  If the kernel value is
#                    empty, the value 'localhost' is used.
#
#                    MODIFIED TO USE /boot/newhost file to change
#                    the /etc/hosts and /etc/hostname on start
### END INIT INFO

PATH=/sbin:/bin

. /lib/init/vars.sh
. /lib/lsb/init-functions

do_start () {

        if [ -f /boot/newhost ]
        then
          OLDHOST=`cat /etc/hostname`
          NEWHOST=`cat /boot/newhost`
          echo "Changing $OLDHOST to $NEWHOST..."
          echo $NEWHOST > /etc/hostname
          sed -i "s/127.0.1.1.*$OLDHOST/127.0.1.1\t$NEWHOST/g" /etc/hosts
          rm /boot/newhost
        fi
        
        [ -f /etc/hostname ] && HOSTNAME="$(cat /etc/hostname)"

        # Keep current name if /etc/hostname is missing.
        [ -z "$HOSTNAME" ] && HOSTNAME="$(hostname)"

        # And set it to 'localhost' if no setting was found
        [ -z "$HOSTNAME" ] && HOSTNAME=localhost

        [ "$VERBOSE" != no ] && log_action_begin_msg "Setting hostname to '$HOSTNAME'"
        hostname "$HOSTNAME"
        ES=$?
        [ "$VERBOSE" != no ] && log_action_end_msg $ES
        exit $ES
}

do_status () {
        HOSTNAME=$(hostname)
        if [ "$HOSTNAME" ] ; then
                return 0
        else
                return 4
        fi
}

case "$1" in
  start|"")
        do_start
        ;;
  restart|reload|force-reload)
        echo "Error: argument '$1' not supported" >&2
        exit 3
        ;;
  stop)
        # No-op
        ;;
  status)
        do_status
        exit $?
        ;;
  *)
        echo "Usage: hostname.sh [start|stop]" >&2
        exit 3
        ;;
esac

:

This is a modified version of /etc/init.d/hostname.sh script on the Raspberry Pi that looks for a /boot/newhost file. If found, it takes the name found in that file and replaces the current contents of the /etc/hostname and the entries in the /etc/hosts file to match. It then removes the /boot/newhost to prevent it doing it more than once.