[ -f /etc/hostname ] && HOSTNAME="$(cat /etc/hostname | sed 's/^[\t]*//;s/[ \t]*$//')"

#! /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.
### END INIT INFO

PATH=/sbin:/bin

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

do_start () {
      [ -f /etc/hostname ] && HOSTNAME="$(cat /etc/hostname | sed 's/^[\t]*//;s/[ \t]*$//')"

      # 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