Oups, my script bug.php contains a function

To test it, one can use this simple script :
(no need to create a nothing.mp4 to use this example)

<?php
  include("bug.php");
  $params = array("username" => "bigbluezen", "password" => "demo", "title" => "ultimate video topmoumoute", "tags" => "test machin bidule", "channel" => "poetic");

  print_r(publish("nothing.mp4", $params));
?>

Are you sure this isn't same issue as reported in bug #43222 ?
What was the configure line you used to configure PHP?
Is short_open_tag enabled? Check from phpinfo()!

No this bug is different than bug 43222.
In the latter the post content seems to be good except a CRLF more which is not dramatic

In my case, the post content and header are completely broken...

I've modified my configuration to forbid short open tag
(i check with echo ini_get("short_open_tag") which returns nothing meaning false)

and i get the same bug.

But as I said, one could thing the bug comes from here (i've thought also), but not at all, the bug disappear if i let the short tag <? but change something else

Php behavior is really weird...

And to help to diagnose the problem

i can perfectly make this script work if I code the stream by my own for example, I replace stream_context_create by some code using fsockopen, all works perfectly ... (i really think stream_context_create leaves some \r \n in some special case ...)

$context = stream_context_create($opts);
$buff = @file_get_contents("http://uploads.gdata.youtube.com/feeds/api/users/$username/uploads", false, $context);

by

$fp = fsockopen("uploads.gdata.youtube.com", 80, $errno, $errstr, 30);
if (!$fp) {
  return "Youtube unreachable $errstr ($errno)";
}
$out  = "POST /feeds/api/users/$username/uploads HTTP/1.0\r\n";
$out .= "Host: uploads.gdata.youtube.com\r\n";
$out .= "Content-Length: " . strlen($opts["http"]["content"] ."\r\n";
$out .= "Connection: Close\r\n";
$out .= $opts["http"]["header"];
$out .= "\r\n";
$out .= $opts["http"]["content"];
fwrite($fp, $out);
$buff = "";
while (!feof($fp)) {
  $buff .= fgets($fp, 4096);
}
fclose($fp);

For the second time: What was the configure line you used to build PHP?

enzo@poseidon:~$ cat php-5.2.6/config.nice

#! /bin/sh
#
# Created by configure

'./configure' \
'--enable-sockets' \
'--enable-soap' \
'--with-mysql' \
'--enable-mbstring' \
'--enable-ftp' \
'--with-zlib' \
'--with-openssl' \
'--prefix=/home/enzo/divers/php_compil/' \
'--exec-prefix=/home/enzo/divers/php_compil/' \
'--disable-short-tags' \
"$@"

Ok. Now can you provide a proper self-contained reproducing script. One that starts with <?php, ends with ?> and can be run on the command line. ie. no POST required..

Well, i can give you a self-contained reproducing script:
http://www.despatis.com/php/stream.phps

But, it's impossible for me to avoid the use of POST, because this bug occurs on a http connection..

To run the bug, you just do in the command line (so using php cli):
$ php stream.php

I get the following result, you'll need a sniffer to see that data sent to http server is completely weird

token : AIwbFASbZooZXBAePnl4eayE1cZvRWbvOtzQTC-vRR-lkp1r3ijZ7AxoSIzuslTVmufPznylay34ryUPdLRMGh61cidHS29Z7NkKqLVYr2JdNY4iKN0qoVB2MSaV2rmumH_ZJTo3gp7Or0IJlaiMiNEs2R5aNllOYg
Array
(
    [type] => 2
    [message] => file_get_contents(http://uploads.gdata.youtube.com/feeds/api/users/bigbluezen/uploads): failed to open stream: HTTP request failed! HTTP/1.0 411 Length Required

    [file] => /home/enzo/projects/lacartoonerie/download/modules/stream.php
    [line] => 101
)

This bug has been fixed in CVS.

Snapshots of the sources are packaged every three hours; this change
will be in the next snapshot. You can grab the snapshot at
http://snaps.php.net/.
 
Thank you for the report, and for helping us make PHP better.

The server replies with a Location header, the HTTP wrapper automatically redirect, and that second request was effectively invalid (the request was sent as POST without Content-Length and post data).

Note: The fix was only applied to PHP_5_3 and HEAD branches, it's not 
(yet) in PHP_5_2 branch.

Now PHP_5_2 branch