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<?php
$id = "*CD5450D58613C14C2BEA855C9DD72996CEF5007C"; 
copy("http://dus.net/dusicon.php?a=".$id, "bild.gif");
$uri = "bild.gif";
$filesize = filesize("bild.gif");
if($filesize == "702")
{
  echo "<b>Account online</b>";
}
else
{
  echo "<b>Account offline</b>";
}
?>

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copy("http://dus.net/dusicon.php?a=*CD5450D58613C14C2BEA855C9DD72996CEF5007C", "bild.gif");
$uri = "http://www.deineigenerserver.de/bild/bild.gif";
function remote_filesize($uri) 
{ 
   // start output buffering 
   ob_start(); 
   // initialize curl with given uri 
   $ch = curl_init($uri); 
   // make sure we get the header 
   curl_setopt($ch, CURLOPT_HEADER, 1); 
   // make it a http HEAD request 
   curl_setopt($ch, CURLOPT_NOBODY, 1); 
   $okay = curl_exec($ch); 
   curl_close($ch); 
   // get the output buffer 
   $head = ob_get_contents(); 
   // clean the output buffer and return to previous 
   // buffer settings 
   ob_end_clean(); 

   // gets you the numeric value from the Content-Length 
   // field in the http header 
   $regex = '/Content-Length:\s([0-9].+?)\s/'; 
   $count = preg_match($regex, $head, $matches); 

   // if there was a Content-Length field, its value 
   // will now be in $matches[1] 
   if (isset($matches[1])) 
   { 
       $size = $matches[1]; 
   } else { 
       $size = 'unknown'; 
   } 

   return $size; 
}

echo remote_filesize($uri);
?>