"session_start(): Cannot send session cache limiter" warning, using ajax - php

I am having this error in PHP:
session_start(): Cannot send session cache limiter - headers already
sent
I know I have to put session_start() even before the html <head>, what I am doing. The issue here is that I am using id containers for ajax generated content.
For example, I have a button in the homepage.php which updates some calculate.php file in a divResults, and this calculate.php begins with session_start(). However, this warning is appearing inside divResults.
How could I solve it. Is it possible to simply ignore the warning. How?
(I don't have this problem in XAMPP, only using an external hosting provider)
Thanks

Based on your problem following errors may possible.
you write session_start(); in somewhere middle or end of the .php file so you need to put session_start();at top of .php file just after <?php.
May be some empty lines are there in your .php file at the beginning or end, because of that also this error will arise. remove those empty line.

Related

session cache error only on two pages - All other pages are working fine

I developed a website from a developer. My website was working fine. All of a sudden I discovered that whenever I click on Contact Us link, I get an error
"Warning: session_start() Cannot send session cache limiter - heards
already sent (output started at /home/xxx/public_html/contact.php:1)
in /home/xxx/public_html/connection/config.php on line 2"
This was not happenning before. The developer is not giving me support and is ignoring my emails. So I searched and researched for it a lot on the Internet and found that there is something wrong in the way session_start() is defined.
Here is the code of contact.php
<?php
include("connection/config.php");
session_start();
?>
<?php
if(isset($_POST['enquiry2']))
{
.
.
.
}
?>
<!DOCTYPE html PUBLIC
.
.
.
<?php include "footer.php"; ?>
</html>
Code of config.php
<?php
session_start();
error_reporting(0);
if ($_SERVER['HTTP_HOST'] == 'localhost' || $_SERVER['HTTP_HOST'] == '192.168.1.111')
{
$con=
.
.
}
else
{
$con=
.
.
}
error_reporting(E_NOTICE ^ E_WARNING ^ E_ALL);
require_once("logic/class.config.php");
.
.
<?php date_default_timezone_set("Asia/Kolkata");?>
In lot of articles I read that session_start() should be right at the top of the page so I reversed the second and third line of contact.php but it gave me same error pointing to contact.php file.
"Warning: session_start() Cannot send session cache limiter - heards
already sent (output started at /home/xxx/public_html/contact.php:1)
in /home/xxx/public_html/connection/contact.php on line 2"
Earlier it was pointing to config.php fle
Same thing is happening in registration page. I have three files register.php, register1.php and register2.php. The same error occurs only on register3.php when it loads the page and once again when submit button is clicked.
I request if someone can help me identify the problem.
Thanks.
EDIT
As suggested by Premalatha:
Removed session_start(); from contact.php -> but same warning.
Placed session_start(); on top of include("connection/config.php"); -> but same warning.
As suggested by Alok:
I dont know how to check if I am sending content or calling header somewhere before session_start(). The session_start() line is either on top or in the second line with first line being include("connection/config.php"); that I tried interchanging upside down with no help.
One thing I fail to understand that other .php files also have the same coding then why this warning comes only on contact.php? Similarly, register1.php, register2.php also have same coding but why the warning comes only while loading and unloading register3.php. All was working before, this started all of a sudden and I dont remember doing any changes in any of these files so the issue may be something else. I also wanted to try suggestion from wangpeng but I could not find the php.ini file anywhere in cpanel. Moreover, I did not figure out how to check if the file's code if it is UTF8-BOM. Also where exactly should i put OB_START() because i am unable to identify where is the header.
EDIT2
By the way, this warning does not affect the functioning of the site. The error just appears and then disappears. However, it disturbs the css, all fonts and images become bigger and the look of the page goes for a toss. Can someone tell me how to ignore this error so that the system doesn't show it at all?
session_start();
is already included in config.php file.
You can remove in contact.php file and it would start working without any issues.
If you still face any issues then you can place session_start(); line of code in contact.php above the include statement.
1.php.ini session.auto_start = 0 to session.auto_start = 1 .
2.check the file's code is UTF8-BOM? yes,UTF8-BOM to UTF8.
3.OB_START();before header
Headers already sent means PHP script sent the headers to the server already, and it cannot be modified now.
Which means before session_start() your script must be sending content or calling header to the server and and after sending it script is calling session_start() function which tries to modify the headers.
Solution in your case is to check you're not sending content or calling header some where before session_start() in both the scripts.
Update:
Try this,
Locate all the *.php files pointed in contact.php and find session_start(); in it.
Replace it with the following,
if (session_status() == PHP_SESSION_NONE) {
session_start();
}
Above code will make sure that you don't start the session again if it is already being started.
I never thought the solution would be this !
However, when I read same thing from four different people, I had to try this and it worked ! I had few leading, trailing and blank spaces in my include files. I got rid of them and my problem was solved.
Here is the article that helped me a lot
Troubleshooting "Warning: session_start(): Cannot send session cache limiter - headers already sent"
if you have blank space after php tag (or html or any output) in your include files then this error will come. -by Imdad
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). Remove the trailing spaces, newlines etc... and all will be well. -by Chris B
a white-space before <?php also send for output and arise error. Conclusion: Do not output any character before calling session_start() or header() functions not even a white-space or new-line -by Biswadeep Sarkar
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. -by Ross

Getting 302 redirects when testing website on pingdoms and others

I am not able to identify how and where it is happening. When i run a test on pingdom, every 3 out of 5 times it will show in the result that my website www.filliplingua.com is redirected to "/". I am giving the link to the reults below:
http://tools.pingdom.com/fpt/#!/bpgda9/www.filliplingua.com
It is a joomla website. I even reset my .htaccess. And turned off redirect plugin in joomla and cleared all kinds of caches. Still it is showing. Can u please help me find out how to solve is.
If the redirect is originating from PHP it's programmed with the header() function, and that function will throw a warning if the output has already started, because the first output will send the HTTP headers.
PHP Manual about header():
Remember that header() must be called before any actual output is
sent, either by normal HTML tags, blank lines in a file, or from PHP.
It is a very common error to read code with include, or require,
functions, or another file access function, and have spaces or empty
lines that are output before header() is called. The same problem
exists when using a single PHP/HTML file.
So what you can do in index.php is start the file with any output, like echo "here";
and this will trigger a warning when the script is trying to redirect, the redirect will fail, and in the error description (in the log or on the page, depending on your error-reporting settings) you will be able to see what file the redirect originates from. From there, you will probably figure out why it tries to redirect.
Good luck!

jQuery .load and PHP session start

I am currently working on a game in PHP and jQuery and at some point I will need to use the .load() from jQuery to load a PHP page into a div. That page will load some player information based on their login information, account id, etcetera, stored into an array inside $_SESSION["arrayname"].
It works perfectly on all sites, except those where jQuery load() is use. On easyphp, I got no errors, but on my web host server im getting this:
Warning: session_start() [function.session-start]: Cannot send session cache limiter - headers already sent (output started at /fr/game/map.php:1) in fr/game/map.php on line 6
Here is my code:
<?php
require_once("../../connectionRO.inc.php");
//used to check if we see the array in session, and i dont when i load it with jquery
if(!ISSET($_SESSION["comptejeu"]))
{
require_once('../../classInfoCompte.php');
session_start();
require_once('../../lg.php');
require_once("./glg.php");
}
$ic = new infoCompte;
$ic = $_SESSION["comptejeu"];
?>
I understand that at this point a lot of stuff is already output to the page before that is loaded. Could anyone point me to a better way to retrieve the information that I need from that array to build my object from my class?
Thank you.
Since you are getting this error as output started at /fr/game/map.php:1 (note: line 1) I will place money on you having whitespace or a BOM before the opening <?php tag in /fr/game/map.php.
Make sure the opening < is the first character in the file. If you file is UTF-8, make sure it is UTF-8 without BOM, or convert it to ASCII.
Wrong:
<?php
Right:
<?php
Either there is some white space in your PHP file, there is some whitespace in classInfoCompute.php or there is a function/method call that triggers output in either this or the classInfoCompute file. Sessions depend on cookies, and cookies depend on HTTP headers. Once content has been output, the headers are already sent and you can't send a new one.
There are plenty of questions and answers on Stack Overflow that cover this issue, but it boils down to either sweeping the problem under the carpet (with output buffering), or fixing it properly (by finding what's causing content to be output before your call to session_start and either removing it or moving it to later in the script, or moving session_start to earlier in the script).
If your script mixes HTML and PHP then make sure that the session_start occurs before the first bit of HTML. Otherwise, you'll have to hunt around for white space. If the file is saved as UTF-8 then your text editor might have attached an unnecessary Byte Order Mark (BOM) to the start of the file. Make sure that your file is being saved without a BOM, because it will be treated as content and trigger output to the client (and put a weird character at the start of the output).

How do I carry over a php session from one page to another via Javascript?

I have a form (form.php) that uses the following JS code in the header:
<script type="text/javascript">
$(document).ready(function(){
$("a").click(function(){
$.post('test.php', function(data) {
$('#test').html(data);
});
});
});
</script>
A have a link in form.php that once clicked I want a drop down to appear (without refreshing the page) e.g. "Display drop down". The code in the drop down is managed in test.php.
Test.php pulls data in from another service. In order to do get this data I use data that is kept in the session e.g. $_SESSION['data_that_is_sent_to_another_service'].
I start the session in form.php but in order for the test.php to get the information from the other service I need to start a session at the start of test.php.
The code works, but I then get a warning saying:
Warning: session_start() [function.session-start]:
Cannot send session cache limiter - headers already sent
(output started at /..my directory.../test.php:1) in /...my directory.../hrdeals.php on line 4
How can I get this warning not to appear (without turning off warnings in PHP)?
Any help much appreciated.
Gregor
PS - the JS might not be correct, but it's more the SESSION issue that I can solve
session_start() must be called before outputing anything to the browser. Check test.php and make sure there is no output.
Javascript and PHP Sessions have nothing to do with one another. Javascript lives in its little bubble (client side rendering/processing). PHP lives in its bubble (server side processing/output).
The error you get is (briefly) - headers already sent.
This refers to http headers (not the head tag where you may have some javascript). You can see the whole list here: http://en.wikipedia.org/wiki/List_of_HTTP_header_fields
This error occurs when you start rendering web page stuff before outputting a header. All headers must be completed first.
Check that all echos and prints from php are occurring after session_start() occurs. One tricky place that printing creeps in is when you end php tags and have anything there - even when it's at the end of a page. You don't need ending php tags at the end of your pages and even a space following one will cause this kind of problem. The safest thing is to just remove all ending php tags at the bottom of your php files.
Another tricky thing is that this kind of error is also caused by a "Byte Order Mark" being output by your code editor. You can try opening, fixing and saving the page in just a simple plain-text editor and see if that fixes the problem.

session_start() error

I can't handle this error, please help me. It worked on my laptop but did not work on my desktop.
Why?
Warning: session_start() [function.session-start]: Cannot send session cache limiter - headers already sent (output started at F:\xampp\htdocs\etest\index.php:1) in F:\xampp\htdocs\etest\common\header.php on line 3
The code:
<?php
ob_start();
session_start();
include("constants.php");
include("includes.php");
?>
Thanks for your kindness!
the error was at F:\xampp\htdocs\etest\common\header.php on line 3 but output was already started at F:\xampp\htdocs\etest\index.php:1
I assume you posted the header.php, but your index.php either has whitespace before the
<?php include() or outputs something other than a header on the first line.
the error is caused by line one of index.php, whatever is there. I'd guess whitespace.
In general, when you see "headers already sent", it means that you are trying to do something that requires an HTTP header to be set, but you have already sent content to the client. When using HTTP, you have to send the headers, then the content comes after. If you've sent content, you've missed your opportunity to send headers.
Start the session on top of the file.
direct afer the php tag when you make an echo or send some header before you get this errormessage.
<?php
session_start();
ob_start();
include("constants.php");
include("includes.php");
?>
Enable output buffering by configuration. This way it will start before anything else, so it certainly solves your problem. Although you should look at your code and find the cause of the present error, because it seems you do not fully understand your site yet.
After enabling output buffering by configuration, you no longer need to call ob_start() manually.
Create a file called .htaccess with this content:
php_flag output_buffering on
... or add this line to your php.ini:
output_buffering = On
use_only_cookies=0 to use_only_cookies=1 in php.ini file
I encountered the same problem in xampp 7.0.1 and this fixed it. Read it here.
Yes start the session on top of the file amd make sure you do not have a space before
<?php
Plus you can call session_start(); only one time
session_start() must be called before there is ANY other output. The error is telling you that output started on index.php line 1. The call to session_start() must be placed before that.
Put this code inside includes.php
ob_start();
session_start();
And remove the same code from every other page.
Also make sure that in your files there is no whitespace before the initial
(specifically you are getting the error because something is wrong on the first line of index.php not of header.php)
I was getting this even when I had it at the top of the file.
Problem INVISIBLE UTF8 CHARACTER
Solution
Was to delete the file and make a new one starting with <?php and then copy everything after the php into the new one. (Don't copy the beginning of the file).

Categories