title: Notice: Use of undefined constant
body: <p>I am having issues with this login script i found (open source btw). For some reason i am getting the following errors:
  note where you see "---" i have removed something for a reason! Would appreciate it if someone helped me with this :)</p>
  
  <pre><code>Notice: Use of undefined constant dfengineid - assumed 'dfengineid' in C:\xampp\htdocs\---\resources\login.php on line 113
  
  Warning: Cannot modify header information - headers already sent by (output started at C:\xampp\htdocs\---\index.php:217) in C:\xampp\htdocs\dfengine.com\resources\login.php on line 113
  
  Notice: Use of undefined constant dfenginekey - assumed 'dfenginekey' in C:\xampp\htdocs\---\resources\login.php on line 115
  
  Warning: Cannot modify header information - headers already sent by (output started at C:\xampp\htdocs\---\index.php:217) in C:\xampp\htdocs\dfengine.com\resources\login.php on line 115
  
  Warning: Cannot modify header information - headers already sent by (output started at C:\xampp\htdocs\---\index.php:217) in C:\xampp\htdocs\dfengine.com\resources\login.php on line 121
  </code></pre>
  
  <p>
  
  <pre><code> &lt;?php 
  
  // Connects to your Database 
  
   mysql_connect("localhost", "root", "---") or die(mysql_error()); 
   mysql_select_db("dfeuserdb") or die(mysql_error()); 
  
   //This code runs if the form has been submitted
   //Checks if there is a login cookie
   if(isset($_COOKIE['dfengineid']))
   //if there is, it logs you in and directes you to the members page
   { 
      $username = $_COOKIE['dfengineid']; 
      $pass = $_COOKIE['dfenginekey'];
      $check = mysql_query("SELECT * FROM users WHERE username = '$username'")or die(mysql_error());
  
      while($info = mysql_fetch_array( $check ))  
      {
          if ($pass != $info['password']) {}
          else
          {
              header("Location: search.php");
          }
      }
   }
  
   //if the login form is submitted     
   if (isset($_POST['submit'])) { // if form has been submitted
  
      // makes sure they filled it in  
      if(!$_POST['username'] | !$_POST['pass']) {    
          die('You did not fill in a required field.');
      }
  
      // checks it against the database
      $check = mysql_query("SELECT * FROM users WHERE username = '".$_POST['username']."'")or die(mysql_error());
  
      //Gives error if user dosen't exist
      $check2 = mysql_num_rows($check);
      if ($check2 == 0) {
          die('Username or Password is incorrect! Please &lt;a href="index.php"&gt;try again&lt;/a&gt;.');
      }
  
      while($info = mysql_fetch_array( $check )){
          $_POST['pass'] = stripslashes($_POST['pass']);
          $info['password'] = stripslashes($info['password']);
          $_POST['pass'] = md5($_POST['pass']);
  
      //gives error if the password is wrong
  
          if ($_POST['pass'] != $info['password']) {
              die('Username or Password is incorrect! Please &lt;a href="index.php"&gt;try again&lt;/a&gt;.');
          }
          else { 
              // if login is ok then we add a cookie 
              $_POST['username'] = stripslashes($_POST['username']); 
              $hour = time() + 3600; 
              setcookie(dfengineid, $_POST['username'], $hour); 
              setcookie(dfenginekey, $_POST['pass'], $hour);   
              //then redirect them to the members area 
              header("Location: members.php"); 
          } 
      } 
  } 
  else {   
   // if they are not logged in 
   ?&gt; 
  
   &lt;form action="&lt;?php echo $_SERVER['PHP_SELF']?&gt;" method="post"&gt; 
   &lt;table border="0"&gt; 
   &lt;tr&gt;&lt;td&gt;Username:&lt;/td&gt;&lt;td&gt; 
   &lt;input type="text" name="username" maxlength="40"&gt; 
   &lt;/td&gt;&lt;/tr&gt; 
   &lt;tr&gt;&lt;td&gt;Password:&lt;/td&gt;&lt;td&gt; 
   &lt;input type="password" name="pass" maxlength="50"&gt; 
   &lt;/td&gt;&lt;/tr&gt;    
   &lt;tr&gt;&lt;td colspan="2" align="right"&gt; 
   &lt;input type="submit" name="submit" value="Login"&gt; 
   &lt;/td&gt;&lt;/tr&gt; 
   &lt;/table&gt; 
   &lt;/form&gt; 
  
   &lt;?php } ?&gt; 
  </code></pre>
  
  <p>Note: issue resolved I placed the code in the wrong place and therefore got all these errors.</p>