i am getting Warning: session_start() [function.session-start]: Cannot send session cache limiter - headers already sent (output started at error
If i submit form data to a different file for processing, it works. But if i submit form data to the same page, it gives this error.
please suggst
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
<html xmlns="http://www.w3.org/1999/xhtml">
<head>
<meta http-equiv="Content-Type" content="text/html; charset=UTF-8" />
<link href="style.css" rel="stylesheet" type="text/css" />
<title>Welcome</title>
<script type="text/javascript" src="jquery.js"></script>
<script type="text/javascript">
$(document).ready(function () {
$('#nav li').hover(
function () {
//show its submenu
$('ul', this).slideDown(100);
},
function () {
//hide its submenu
$('ul', this).slideUp(100);
}
);
});
</script>
</head>
<body>
<table width="100%" border="0" cellspacing="0" cellpadding="0">
<tr>
<td class="header"> </td>
</tr>
<tr>
<td class="menu"><table align="center" cellpadding="0" cellspacing="0" width="80%">
<tr>
<td>
<ul id="nav">
<li><a href="#">Catalog</a>
<ul><li><a href="#">Products</a></li>
<li><a href="#">Bulk Upload</a></li>
</ul>
<div class="clear"></div>
</li>
<li><a href="#">Purchase </a>
</li>
<li><a href="#">Customer Service</a>
<ul>
<li><a href="#">Contact Us</a></li>
<li><a href="#">CS Panel</a></li>
</ul>
<div class="clear"></div>
</li>
<li><a href="#">All Reports</a></li>
<li><a href="#">Configuration</a>
<ul> <li><a href="#">Look and Feel </a></li>
<li><a href="#">Business Details</a></li>
<li><a href="#">CS Details</a></li>
<li><a href="#">Emaqil Template</a></li>
<li><a href="#">Domain and Analytics</a></li>
<li><a href="#">Courier</a></li>
</ul>
<div class="clear"></div>
</li>
<li><a href="#">Accounts</a>
<ul><li><a href="#">Ledgers</a></li>
<li><a href="#">Account Details</a></li>
</ul>
<div class="clear"></div></li>
</ul></td></tr></table></td>
</tr>
<tr>
<td valign="top"><table width="80%" border="0" align="center" cellpadding="0" cellspacing="0">
<tr>
<td valign="top"><table width="100%" border="0" cellspacing="0" cellpadding="2">
<tr>
<td width="22%" height="327" valign="top"><table width="100%" border="0" cellspacing="0" cellpadding="2">
<tr>
<td> </td>
</tr>
<tr>
<td height="45"><strong>-> Products</strong></td>
</tr>
<tr>
<td height="61"><strong>-> Categories</strong></td>
</tr>
<tr>
<td height="48"><strong>-> Sub Categories</strong></td>
</tr>
</table></td>
<td width="78%" valign="top"><table width="100%" border="0" cellpadding="0" cellspacing="0">
<tr>
<td> </td>
</tr>
<tr>
<td>
<table width="90%" border="0" cellspacing="0" cellpadding="0">
<tr>
<td width="26%"> </td>
<td width="74%"><h2>Manage Categories</h2></td>
</tr>
</table></td>
</tr>
<tr>
<td height="30">
</td>
</tr>
<tr>
<td>
</td>
</tr>
<tr>
<td>
<table width="49%" align="center" cellpadding="0" cellspacing="0">
<tr><td>
<?php
if (isset($_SESSION['error']))
{
echo "<span id=\"error\"><p>" . $_SESSION['error'] . "</p></span>";
unset($_SESSION['error']);
}
?>
<form action="<?php echo $_SERVER['PHP_SELF']; ?>" method="post" enctype="multipart/form-data">
<p>
<label class="style4">Category Name</label>
<input type="text" name="categoryname" /><br /><br />
<label class="style4">Category Image</label>
<input type="file" name="image" /><br />
<input type="hidden" name="MAX_FILE_SIZE" value="100000" />
<br />
<br />
<input type="submit" id="submit" value="UPLOAD" />
</p>
</form>
<?php
session_start();
require("includes/conn.php");
function is_valid_type($file)
{
$valid_types = array("image/jpg", "image/jpeg", "image/bmp", "image/gif", "image/png");
if (in_array($file['type'], $valid_types))
return 1;
return 0;
}
function showContents($array)
{
echo "<pre>";
print_r($array);
echo "</pre>";
}
$TARGET_PATH = "images/category";
$cname = $_POST['categoryname'];
$image = $_FILES['image'];
$cname = mysql_real_escape_string($cname);
$image['name'] = mysql_real_escape_string($image['name']);
$TARGET_PATH .= $image['name'];
if ( $cname == "" || $image['name'] == "" )
{
$_SESSION['error'] = "All fields are required";
header("Location: managecategories.php");
exit;
}
if (!is_valid_type($image))
{
$_SESSION['error'] = "You must upload a jpeg, gif, or bmp";
header("Location: managecategories.php");
exit;
}
if (file_exists($TARGET_PATH))
{
$_SESSION['error'] = "A file with that name already exists";
header("Location: managecategories.php");
exit;
}
if (move_uploaded_file($image['tmp_name'], $TARGET_PATH))
{
$sql = "insert into Categories (CategoryName, FileName) values ('$cname', '" . $image['name'] . "')";
$result = mysql_query($sql) or die ("Could not insert data into DB: " . mysql_error());
header("Location: mangaecategories.php");
exit;
}
else
{
$_SESSION['error'] = "Could not upload file. Check read/write persmissions on the directory";
header("Location: mangagecategories.php");
exit;
}
?>
Here is the code for Display
<?php
require("includes/conn.php");
$sql = "select CategoryID, CategoryName, FileName, Status from Categories";
$result = mysql_query($sql) or die ("Could not access DB: " . mysql_error());
while ($row = mysql_fetch_assoc($result))
{
echo "<table border='0' cellpadding='10'>";
echo "<tr><td> </td><td>Category ID</td><td>Category Name</td><td>Status</td><td>Edit</td><td>Delete</td></tr>";
echo "<tr><td> <img src=\"images/" . $row['FileName'] . "\" alt=\"\" /> </td>";
echo "<td>". $row['CategoryID'] . "</td>";
echo "<td>". $row['CategoryName'] . "</td>";
echo "<td>". $row['Status']. "</td>";
echo "<td> <a href= 'edit.php?CategoryID=" .$row['id']. "'> Edit </a></td>";
echo "<td> <a href= 'delete.php?CategoryID=" .$row['id']. "'> Edit </a></td>";
echo "</tr> </table>";
}
?>
Nothing is happening here. Please suggest
Check any extra space before php tag.
In my case I had to set the file encoding without BOM.
use ob_start(); before session_start(); at top of your page like this
<?php
ob_start();
session_start();
replace session_start(); with @session_start(); in your code
This should solve your problem. session_start() should be called before any character is sent back to the browser. In your case, HTML and blank lines were sent before you called session_start(). Documentation here.
To further explain your question of why it works when you submit to a different page, that page either do not use session_start() or calls session_start() before sending any character back to the client! This page on the other hand was calling session_start() much later when a lot of HTML has been sent back to the client (browser).
The better way to code is to have a common header file that calls connects to MySQL database, calls session_start() and does other common things for all pages and include that file on top of each page like below:
include "header.php";
This will stop issues like you are having as also allow you to have a common set of code to manage across a project. Something definitely for you to think about I would suggest after looking at your code.
<?php
session_start();
if (isset($_SESSION['error']))
{
echo "<span id=\"error\"><p>" . $_SESSION['error'] . "</p></span>";
unset($_SESSION['error']);
}
?>
<form action="<?php echo $_SERVER['PHP_SELF']; ?>" method="post" enctype="multipart/form-data">
<p>
<label class="style4">Category Name</label>
<input type="text" name="categoryname" /><br /><br />
<label class="style4">Category Image</label>
<input type="file" name="image" /><br />
<input type="hidden" name="MAX_FILE_SIZE" value="100000" />
<br />
<br />
<input type="submit" id="submit" value="UPLOAD" />
</p>
</form>
<?php
require("includes/conn.php");
function is_valid_type($file)
{
$valid_types = array("image/jpg", "image/jpeg", "image/bmp", "image/gif", "image/png");
if (in_array($file['type'], $valid_types))
return 1;
return 0;
}
function showContents($array)
{
echo "<pre>";
print_r($array);
echo "</pre>";
}
$TARGET_PATH = "images/category";
$cname = $_POST['categoryname'];
$image = $_FILES['image'];
$cname = mysql_real_escape_string($cname);
$image['name'] = mysql_real_escape_string($image['name']);
$TARGET_PATH .= $image['name'];
if ( $cname == "" || $image['name'] == "" )
{
$_SESSION['error'] = "All fields are required";
header("Location: managecategories.php");
exit;
}
if (!is_valid_type($image))
{
$_SESSION['error'] = "You must upload a jpeg, gif, or bmp";
header("Location: managecategories.php");
exit;
}
if (file_exists($TARGET_PATH))
{
$_SESSION['error'] = "A file with that name already exists";
header("Location: managecategories.php");
exit;
}
if (move_uploaded_file($image['tmp_name'], $TARGET_PATH))
{
$sql = "insert into Categories (CategoryName, FileName) values ('$cname', '" . $image['name'] . "')";
$result = mysql_query($sql) or die ("Could not insert data into DB: " . mysql_error());
header("Location: mangaecategories.php");
exit;
}
else
{
$_SESSION['error'] = "Could not upload file. Check read/write persmissions on the directory";
header("Location: mangagecategories.php");
exit;
}
?>
For others who may run across this - it can also occur if someone carelessly leaves trailing spaces from a php include file. Example:
<?php
require_once('mylib.php');
session_start();
?>
In the case above, if the mylib.php has blank spaces after its closing ?> tag, this will cause an error. This obviously can get annoying if you've included/required many files. Luckily the error tells you which file is offending.
HTH
The answer is above by Ross.
Firstly, putting session_start() as the first line of code will mean that you cannot deserialise any objects correctly into session variables.
The reason for getting this issue is 99% likely to be trailing spaces at the end of your include files (yes - I know it sounds unlikely but just try it). The offending file is in the error message. I wanted to back up Ross answer which worked for me but this site is counter intuitive.
IGNORE the nonsense answers. Remove the trailing spaces, newlines etc... and all will be well. ROSS knows what he is talking about. Putting session_start() at the top of your file DOES work but it isnt the correct solution.
Just replace session_start with this.
if (!session_id() && !headers_sent()) {
session_start();
}
You can put it anywhere, even at the end :) Works fine for me. $_SESSION is accessible as well.
I had the same issue, but my solution wasn't as obvious as the suggested ones. It turned out that my php-file was written in UTF-8, which caused issues. I copy/pasted the content of the entire file into a new php-file (Notepad++ tells me this is written in ANSI rather than UTF-8), and now it work flawlessly.
use session_start() at the top of the page.
for more details please read the link session_start
I had a website transferring from one host to another, it seemed to work fine on the old host but a few pages on the new host threw the error
Warning: session_start(): Cannot send session cache limiter - headers already sentwhile I always kept the
<?php session_start();
at the top of the page no spaces and nothing inserted before
it really bugged me that I stared every page with the session opening, and it worked on some pages and run through a bug on others I picked the pages that had the problems, backed them up, created new blank pages and simply copied and pasted the code as is, saved and uploaded and boom, problem gone!
this is something you guys may need to consider, it may have been the encoding of the page, or something, not sure the exact source of the problem, but here is a fix to look at in case you guys run into a similar problem
cheers!
Generally this error arise when we send header after echoing or printing. If this error arise on a specific page then make sure that page is not echoing anything before calling to start_session().
Example of Unpredictable Error:
<?php //a white-space before <?php also send for output and arise error
session_start();
session_regenerate_id();
//your page content
One more example:
<?php
includes 'functions.php';
?> <!-- This new line will also arise error -->
<?php
session_start();
session_regenerate_id();
//your page content
Conclusion: Do not output any character before calling session_start() or header() functions not even a white-space or new-line
This started for me when I redirected my site to https:// (for SSL Certificate). From my experience with this issue, the session_start() had to be before the browser saw any HTML code. For my example, I was using session_start() in nav.php to determine the options of the navigation bar. I ended up placing session_start() right after the php comments in the index.php file and every page which called nav.php. I was able to keep the php comments before session_start() but could not keep the HTML comments above the php.
I was able to solve similar Warning: session_start(): Cannot send session cache limiter - headers already sent by just removing a space in front of the <?php tag.
It worked.
Source: Stackoverflow.com