title: how to extract exact value from xml file in unix
body: <p>i have this below sample file with more than 1000 entry. I want to extract the session id.
  Sample output should be <code>sessionId="1308130606029610103"</code>.</p>
  
  <pre><code>&lt;cdr-data&gt;
      &lt;cdr&gt;
          &lt;networkInfo payer="830459" payerType="0" pdpAddress="2" pdpType="0"
                       ratingGroup="2" redirectionCode="0" requestType="1006"
                       sequenceNumber="12" serviceIdentifier="0"
                       sessionId="1308130606029610103" sgsnAddress=""
                       sgsnMccMnc="" specialLocationClassId="0" spendControlId="0"
                       tariffToken="0" timeZone="" unitType="2"/&gt;
  
      &lt;/cdr&gt;
      &lt;cdr-data&gt;
  </code></pre>