title: Read kernel timestamps in user space for tcp packets in linux
body: <p>I am new to linux and trying to work with kernel.
  I want the time taken for kernel to transmit a stream of data in TCP. To achive this i would  read linux kernel timestamps that is when packet arrived to kernel  or when packet was sent from kernel. So that by taking first packet time time and last packet time and subtract them and will get required kernel time.</p>
  
  <p>As per RFC1323 we have some timestamp option in tcp header options field, but i dont understand how to ream them in userspace. please suggest if any quick way i can do this.</p>
  
  <p>Any help would really usefull for me.</p>
  
  <p>Thanks.</p>