title: how to use dd to read and seek different block size
body: <p>I have a situation where i have to read sparse file. This file is having data at specific offset. Now i want to achieve.
  1) Read 3 blocks(custom sizes) from the given offset
  2) offset need to be seek using 1M </p>
  
  <p>So, i am trying below command but not successful. I am reading more contents for sure.</p>
  
  <pre><code>dd if=a_Sparse_file_ofSIZe_1024M of=/dev/null ibs=1M skip=512 obs=262144 count=3
  </code></pre>
  
  <p>skip 512M of blocks and read from 512M+1 th offset using block of 256K for 3 counts.</p>
  
  <p>skip always should be in MBs and count blocks are variable.
  I am sure i am reading more data. Can someone please correct me.</p>