PHP Output buffering contains something before script starts

Question

i have a site, where i buffer some output with

ob_start();
...

and it worked fine until today i updated my debian from an older php5.3 to the latest php5.3.3-7+squeeze8
Now i sometimes have something in the output buffer before i call it the first time

please don't answer things like

"header must be called before any output is sent." (I know, I work a lot with output buffers)

when i set an extra ob_get_clean(); at the very first line of my script, it works

<?
ob_get_clean();

it seems, like php is creating some output beforehand if i put the first line

<? print_r(ob_get_clean()); ?>

then i see, that there is an empty string already in the buffer:

""

on all other pages it isn't, there ob_get_clean(); contains

null

Seen this before .... you don't see it but there is something there ... delete the file and recreate it ... if possible use another editor or just notepad ... — Baba, Apr 09 '12 at 11:44
related to [Headers already sent](http://stackoverflow.com/questions/8028957/headers-already-sent-by-php), see the hexeditor thing and outbut buffering section. — mario, Apr 09 '12 at 20:55

score 0 · Answer 1 · answered Apr 09 '12 at 11:35

0

is it possible you have some " " in front of your <?php somewhere? or wrong file encoding issue its usually some kind of that nature, check your files and include files.

answered Apr 09 '12 at 11:35

worenga

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score 0 · Answer 2 · answered Apr 09 '12 at 11:36

0

Now i sometimes have something in the output buffer before i call it the first time

It'll be much easier if you give us some info about that mysterious data.

answered Apr 09 '12 at 11:36

deadrunk

13,861
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score 0 · Answer 3 · answered Apr 09 '12 at 11:40

0

perhaps a case of BOM character? more info here

answered Apr 09 '12 at 11:40

andrew

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score 0 · Accepted Answer · answered Apr 14 '12 at 01:06

i found it:

i had no invisible character in front, it was something different: i called ob_end_clean() one time too much:

this was my code, inside a function i call:

function print_something(){
ob_start();

echo some stuff...

echo ob_get_clean();
ob_end_clean(); // this was the bug! 
}

it seems, that you can clear your main output buffer ;)

PHP Output buffering contains something before script starts

4 Answers4

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