[katadelos]

This script is probably a good starting point, I use it to cleanly shutdown devices if I need to store them - it's ripped off/adapted from the script used to put a device into shipping mode:

#!/bin/sh

# shutdown.sh
# Simple shutdown script based on /etc/upstart/shutdown_special


source /etc/upstart/functions
source /etc/upstart/upstart_functions

set_background() {
  fbink -c -f
  if [ -f /tmp/bg_shipping.png ]; then
    bg_img=/tmp/bg_shipping.png
  else
    bg_img=/usr/share/blanket/shutdown/bg_shipping.png
  fi
  fbink -g file=$bg_img
}

shutdown_device() {
  echo "shutdown" > /tmp/shutdown_in_progress

  f_log I shutdown "closing password dialog"
  killall -q -s KILL passwdlg || true

  f_upstart_job_stop_timeout 60 "x wifid wifis lab126 framework sshd usbnetd testd" || \
                                          f_log W shutdown "stop_failed" "type=services" "continuing"

  # Shutdown the filesystems
  f_upstart_job_stop_timeout 30 "filesystems" || f_log W shutdown "stop_failed" "type=filesystems" "continuing"

  #
  # Logging went down with filesystems, the following only prints to console
  #
  # Make sure rootfs is readonly (it should be already)
  f_log I shutdown "mounting root filesystem read-only"
  sync || true
  mntroot ro || true

  # Sync the filesystems
  f_log I shutdown "syncing disks"
  sync || true
  echo 3 > /proc/sys/vm/drop_caches || true

  f_log I shutdown "wait for additional 5 seconds to ensure all files have been written to disks"
  sleep 5
  poweroff -f 
}

main() {
  set_background
  shutdown_device
}

main