PHP - Warning: Cannot modify header information - still stuck

Question

I know this has been asked a million times, but I've gone through all the answers to no avail, and as I only have a small amount of code, I figured it's a relatively simple fix (I hope). The frustrating thing is, is that php file works perfectly on one server, but not on another.

I'm receiving this error:

Warning: Cannot modify header information - headers already sent by (output started at /home/thepcguy/public_html/ship_image/functions/function-redirect.php:1) in /home/thepcguy/public_html/ship_image/functions/function-redirect.php on line 9

relating to this file

<?php require_once('../Connections/ships.php');

if ($_GET['shore'] == "1") {
   header('Location: ../shore_establishment.php?ship_id=' .urlencode($_GET['ship_id']) . "&shore=1" . "&page=ship");
   //echo"first";
} else if ($_GET['shore'] == "0") {
  header('Location: ../shipinfo.php?ship_id=' .urlencode($_GET['ship_id']). "&shore=0" . "&page=ship");
   //echo"second";
};

?>

For interests sake, the file ships.php is:

<?php
$hostname_ships = "xxxxx";
$database_ships = "xxxxx";
$username_ships = "xxxxx";
$password_ships = "xxxxx";
$ships = mysql_pconnect($hostname_ships, $username_ships, $password_ships); 
?>

I'll check that one out, but I have looked at several results. thanks — user2406993, Feb 25 '14 at 15:23
What's on line 9 of function-redirect.php? Are you absolutely certain you do not have any output (even whitespaces) in ships.php? — Brian Driscoll, Feb 25 '14 at 15:25
There is probably a space at the beginning or end of one of your files, you will also want to end the current script with a `die` after you set your redirect. — cmorrissey, Feb 25 '14 at 15:25
I'm as certain as I can be that there is no white space on either of the php files... in both cases I have moved the closing ?> to the end of the previous line, and the opening — user2406993, Feb 25 '14 at 15:31

score 4 · Answer 1 · answered Feb 25 '14 at 15:25

4

Most likely you get notification that mysql_* is deprecated, and that is actually outputted to your browser, therefore you can't send headers since output is already sent...

Probably one server doesn't send notification, and other do, that's why it works on one, and not on other. To test set this as first line in you file:

error_reporting(E_ALL ^ E_DEPRECATED);

answered Feb 25 '14 at 15:25

Dexa

1,641
10
25

Thanks Dexa, I have added that code directly after my opening – user2406993 Feb 25 '14 at 15:28
How do you mean it doesn't change output? you are still getting the warning? – Dexa Feb 25 '14 at 15:29
yeah exactly the same warning – user2406993 Feb 25 '14 at 15:31
then comment out header functions and check what's the output... Also check your log files to narrow down the problem. – Dexa Feb 25 '14 at 15:33
@user2406993 also check there no space after ending php tag ?>. this also cause same issue if there is some space or better remove ending tag – Maz I Feb 25 '14 at 15:33
Thanks again Dexa, commenting out the header functions results in a blank page – user2406993 Feb 25 '14 at 15:35
well blank page is what you should get :) check source of the page and look for spaces. – Dexa Feb 25 '14 at 15:37

score 0 · Answer 2 · answered Feb 25 '14 at 15:26

0

You can try to use ob_start() at the top, and add ob_flush() at the end of the script. See if that helps.

answered Feb 25 '14 at 15:26

dsoumgit

63
8

tried that Jamie, to no avail sadly :-( – user2406993 Feb 25 '14 at 15:32

score 0 · Answer 3 · answered Feb 25 '14 at 16:04

0

In a similar vein to Dexa's answer:

If $_GET['shore'] or $_GET['ship_id'] aren't set you will get a PHP notice. Which will start output.

answered Feb 25 '14 at 16:04

Jim

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6
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PHP - Warning: Cannot modify header information - still stuck

3 Answers3