header errors in when using includes behaviour

cspgsl

I have created a left menu and used SSI to insert it into various pages. When I apply the logout user server behavior to the menu and open a page I get the following error. Using DW MX

[QUOTE]Warning: session_start(): Cannot send session cache limiter - headers already sent (output started at /home/pencils/public_html/interview/client/contacts.php:8) in /home/pencils/public_html/interview/includes/left_menu.php on line 3[/QUOTE]

When clicking on the logout user link I get the following error added to the first

Warning: Cannot modify header information - headers already sent by (output started at /home/pencils/public_html/interview/client/contacts.php:8) in /home/pencils/public_html/interview/includes/left_menu.php on line 15

Here is the menu that is included

<?php
//initialize the session
session_start();
// ** Logout the current user. **
$logoutAction = $_SERVER['PHP_SELF']."?doLogout=true";
if ((isset($_SERVER['QUERY_STRING'])) && ($_SERVER['QUERY_STRING'] != "")){
  $logoutAction .="&". htmlentities($_SERVER['QUERY_STRING']);
}
if ((isset($_GET['doLogout'])) &&($_GET['doLogout']=="true")){
  //to fully log out a visitor we need to clear the session varialbles
  session_unregister('MM_Username');
  session_unregister('MM_UserGroup');
  $logoutGoTo = "../interview/logout.php";
  if ($logoutGoTo) {
    header("Location: $logoutGoTo");
    exit;
  }
}
?>

<style type="text/css">
<!--
.h2 {font-size: 110%;
	border-bottom: 1px solid #CCD4E6;
	font-style: italic;
	font-weight:bold;
	}
.label{
	font-size:90%;
	font-weight: bold;
	color:#124272;
}
-->
</style>
<table width="100%" border="1" cellpadding="0" cellspacing="0" class="label">
          <tr>
            <td><h2 align="left">webSite Design Interview </h2></td>
          </tr>
          <tr>
				<td class="label">
				<a href="/interview/client/contacts.php">Style Gallery</a>
				</td>
          </tr>
          <tr>
				<td class="label"><a href="<?php echo $logoutAction ?>">Log Out</a></td>
          </tr>

</table>

Here is the page it is inserted into

<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd">
<html>
<head>
<meta http-equiv="Content-Type" content="text/html; charset=iso-8859-1">
<title>Untitled Document</title>


<style type="text/css">
<!--
.style1 {color: #0000FF}
-->
</style>

<link href="/css/template_style.css" rel="stylesheet" type="text/css">

</head>

<body>
<!-- begin div wrapper = entire page -->
<div id="wrapper">
        <div id="header">
          </div>
        <div id="navbar">
        </div>
            <!-- begin div content = right and left columns -->
            <div id="content">
                    <!-- begin div right = right column -->
              <div id="right">
				<h1>webSite Design Interview</h1>

                  <h2> <img src="/images/websites.jpg" width="80" height="95" hspace="10" align="left">Contacts</h2>

                </div>

                <!-- begin div left = left column -->
                <div id="left">
                    <?php require('../includes/left_menu.php'); ?>
        <!-- end div content = right and left columns -->
                </div>

        </div>
</body>
</html>

I seem to be struggling with headers and sessions so any instruction would be appreciated.
Thanks

Blulagoon

leftmenu.php has session_start() as its first line (apart from the comment).

If you try and include this on a page where the headers have already been sent, it will fail. Do you need session_start within leftmenu.php ?

Blu

cspgsl

Thanks for the reply
No. I just tried that and apparently not. You replied to my post as I was about to return and update it.
I remove the session_start () on the menu file and the 1st warning on opening a page (that includes the menu) dissapears.
The problem now is the logout function. When I click the logout I still get the second warning

Warning: Cannot modify header information - headers already sent by (output started at /home/pencils/public_html/interview/client/contacts.php:8) in /home/pencils/public_html/interview/includes/left_menu.php on line 15

I also added a session_start () to the top of the page (that includes the menu) but sitll get the second warnnig

Blulagoon

You are sending more header information within leftmenu.php, about line 15 as the error message explains.

if ($logoutGoTo) { 
    header("Location: $logoutGoTo"); 
    exit;

Blu.

cspgsl

OK, I think I see... in reading up I find

"Output" includes but is not limited to anything

including any other data on the page like the html?

I created a separate logout page with the following

<?php
session_start();

session_unregister('MM_Username');
session_unregister('MM_UserGroup');

session_destroy();

header("Location: /interview/logout.php");

?>

and it seems to work (no warnings anyway).

Blulagoon

Output generally means anything output to the browser, so even a single <html> will be enough to make it fail. If you require or include a file, and the file where you call the require or include has already output headers, the file required or included will fail.

Going to a separate page, where no headers have been sent, should work.

HTH - Blu

cspgsl

It did, thanks