title: Undefined index with session
body: <p>I'm developing a chatbox script, and I have this page that checks if session is set, and if so, the certain elements of code should be hidden with jQuery. Here are my pages:</p>
  
  <p>input.php: </p>
  
  <pre><code>&lt;!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd"&gt;
  &lt;html xmlns="http://www.w3.org/1999/xhtml"&gt;
  &lt;head&gt;
  &lt;meta http-equiv="Content-Type" content="text/html; charset=iso-8859-1" /&gt;
  &lt;style type="text/css"&gt;
      @import "stil.css";
  &lt;/style&gt;
  &lt;title&gt;Untitled Document&lt;/title&gt;
  &lt;script type="text/javascript" src="jq.js"&gt;&lt;/script&gt;
  &lt;script type="text/javascript" src="jquery-ui-1.8.13.custom.min.js"&gt;&lt;/script&gt;
  &lt;script type="text/javascript" src="scripts.js"&gt;&lt;/script&gt;
  &lt;script type="text/javascript" src="postme.js"&gt;&lt;/script&gt;
  &lt;?php
  include_once('check.php');
  ?&gt;
  &lt;/head&gt;
  &lt;body&gt;
  &lt;div id="wrap"&gt;
      &lt;div id="chat"&gt;
      &lt;div id="main"&gt;
      &lt;/div&gt;
      &lt;div id="input"&gt;
  &lt;form name="form"action="test.php" method="post"&gt;
  &lt;input type="text" name="tekst" id="msg" size="72" /&gt;
  &lt;input type="submit" name="dugme" value="posalji" id="dugme" /&gt;
  &lt;/form&gt;
      &lt;/div&gt;
      &lt;/div&gt;
      &lt;/div&gt;
  &lt;div id="black"&gt;
  &lt;/div&gt;
  &lt;div id="name"&gt;
  &lt;form name="yname"&gt;
  &lt;input type="text" name="tekst2" /&gt;
  &lt;input type="button" name="dugme2" value="Enter" onclick='send()' /&gt;    
  &lt;/form&gt;
  &lt;/div&gt;
  
  
  &lt;/body&gt;
  &lt;/html&gt;
  </code></pre>
  
  <p>sesion.php:</p>
  
  <pre><code>&lt;?php
  session_start();
  $_SESSION['ime']=$_POST['ime'];
  $sesion_n=$_SESSION['ime'];
  echo $sesion_n;
  ?&gt;
  </code></pre>
  
  <p>check.php:</p>
  
  <pre><code>&lt;?php
  include('sesion.php');
  if (!isset($sesion_n)){
      echo "&lt;script type='text/javascript'&gt;$('#black').hide();$('#name').hide();&lt;/script&gt;";
  }
  ?&gt;
  </code></pre>
  
  <p>postme.js:</p>
  
  <pre><code>    function send(){
         $.post('sesion.php',{ime:yname.tekst2.value},function(val){
                  if(val!=null) {
                      $('#black').fadeOut();
                      $('#name').hide();
                      alert(val);  
                  }
  
              }
  
     )};
  </code></pre>
  
  <p>So the problem is that I get this error every time I run the page:
  Notice: Undefined index: ime in C:\wamp\www\AJAX\sesion.php on line 3.<br>
  So can someone tell me what I'm doing wrong here?</p>