Sparse enabled 'dd‘ test

To Check if the 'dd' command is using Sparse :

#!/bin/bash
# set -x

file_name="tttt.img"

`dd if=/dev/zero of=$file_name bs=1024 count=10 seek=10`
 sp_file_size=`du -h $file_name | awk '{print $1}'`
      sp_file_size_app=`du -h --apparent-size $file_name | awk '{print $1}'`

      echo "   Comparing the actual & apparent file sizes ..."
      if [ $sp_file_size == $sp_file_size_app ]; then
          echo "   Failed to create Sparse file: $file_name"
          return 1
      else
          echo "   Sparse file in deed sparsed... "
      fi