md5_cp/calc_md5.sh

#!/bin/bash

cd /mnt/export
md5_tmp=`mktemp`

#sort & del dublicates
sed -i '/^$/d' md5.txt
cat md5.txt | sort -k 2 | uniq > $md5_tmp
cat $md5_tmp > md5.txt

cat $md5_tmp | while read line; do
  #get md5
  md5=$(echo $line | cut -c -32)

  #get path of file
  file=$( echo $line | cut -c  34-)

  #wenn datei existiert
  if [ -f "$file" ]; then
    # do nothing
    echo  > /dev/null
  else
    echo "rm $line"
    sed -i "/$md5/d" md5.txt
  fi

done

#search for new files
find /mnt/export/transport -type f | grep -v "/.Trash-" | sort | while read line; do
  #save fiel path
  result=$(grep "$line" md5.txt); [ -z "$result" ] && {
    #wenn kein eintrag in liste...
    echo "new $line"
    md5sum "$line" >> md5.txt_add
  }
done
[ -f md5.txt_add ] && {
  cat md5.txt_add >> md5.txt
  rm md5.txt_add
}

#sort & del dublicates
cat md5.txt | sort -k 2 | uniq > $md5_tmp
rm md5.txt && mv $md5_tmp md5.txt