title: How to use session in wordpress in plugin development
body: <p>I am new to write a plugin ..I am having a testplugin.php file and a ajax.php file ..</p>
  
  <p>My code in testplugin.php is </p>
  
  <pre><code>global $session;
  
  print_r($abc); //$abc is array of my data ..
  
  $session['arrayImg']=$abc; //saving data in session 
  
  echo  $session['arrayImg']; //displayin "Array"
  </code></pre>
  
  <p>And my ajax.php consists of following code </p>
  
  <pre><code>global $session;
  
  $abc = $session['arrayImg'];
  
  print_r ("abs== ".$abc); //displayin "abs== Array"
  </code></pre>
  
  <p>And if use <code>session_start();</code></p>
  
  <p>I get following error</p>
  
  <pre><code>Warning: session_start() [function.session-start]: Cannot send session cache limiter - headers already sent 
  </code></pre>
  
  <p>I just want to send array of data from one file of my plugin to another file ...</p>