read url inconsistency

[nikosb]

I have problems reading the contents of certain urls and I am very puzzled as to the reason I can not do it succesfully.
I have the following PHP code:
[code]
<?php
Website:
<FORM ACTION='readpage.php'>
<INPUT TYPE='text' NAME='site' VALUE="http://f650.com/phpBB2/" SIZE=80>
<INPUT TYPE='submit' NAME='SEND'>
<BR>
Read webpage using:
<INPUT TYPE='radio' NAME='radio' VALUE='method1'>fopen
<INPUT TYPE='radio' NAME='radio' VALUE='method2'>HTTP-request
<INPUT TYPE='radio' NAME='radio' VALUE='method3' checked>CURL
</FORM>

<?php

if(isset($_GET['site']))
{
  $site = $_GET['site'];
}
else
{
  $site = "http://f650.com/phpBB2/";
}


//Read contents of webpage using fopen function.
if($_GET['radio']=='method1'){
  $file = fopen ($site, 'r') or die($php_errormsg);
  if (!$file) {
    echo "<p>Unable to open remote file.\n";
    exit;
  }
  else {
    while (!feof ($file)) {
      $line = fgets ($file, 1024);
      $page .= $line;
    }
    fclose($file);
  }
}


//Read contents of webpage using HTTP-Request method.
if($_GET['radio']=='method2'){
    require 'HTTP/Request.php';

    $r = new HTTP_Request($site);
    $r->sendRequest();
    $page = $r->getResponseBody();
}


//Read contents of webpage using the CURL method.
if($_GET['radio']=='method3'){

    $c = curl_init($site);
    curl_setopt($c, CURLOPT_RETURNTRANSFER, 1);
    $page = curl_exec($c);
    curl_close($c);
}

echo $page;

?>
[/code]
The function of this code is to read the contents of the url provided by the user. The user can also select the method (fopen, HTTP-Request, or CURL) with which to read the url. I posted the code at
http://www.eng.umd.edu/enme331/readpage.php for you to try. Here are two good examples:

Example 1.
So when reading a particular website (f650.com/phpBB2/) the relative links are not correct. For example the relative link to "General Discussion" forum should be
"viewforum.php?f=8"
However when I read the file with the program the relative link changes to:
"viewforum.php?f=8&sid=72b8381c30fdfdeb6e1cd8a51abed1ef"
Why does the program read different the contents of the url? What is also more confusing is that when I use a different method to read the same url the relative link is not only wrong but it is also different. For example I get a different relative link with CURL than with FOPEN or HTTP_REQUEST. Any ideas what is wrong here?

Example 2
When reading the contents of another forum (just type http://www.zend.com/forums/index.php?t=thread&frm_id=11& amp;S=5def8a6aed7aca4169a2925e00a30e5a in the website input) I also get the same strange behavior. The relative link to one of the threads named "Hi anyone can help me?" is
index.php?t=msg&th=2424&start=0&S=5def8a6aed7aca 4169a2925e00a30e5a
The php program read a different relative link:
index.php?t=msg&th=2424&start=0&S=6e1ed0488ac1a7 2744e5820fa2e6bb9f

I have looked at my code a lot of times and I don't see anything obvious that would create this strange behavior. What am I missing?

Thank you,

Nikolaos