Getting success response for Posting XML Data from PHP & curl

I have done the following code for the solution:

<?php

$url = "http://posttestserver.com/post.php";  // test post server
$file="file.xml";


if (file_exists($file)) { // check file existance

$headers = array(
'Content-Type: text/xml',
'Accept: text/html,application/xhtml+xml,application/xml;q=0.9,*/*;q=0.8',
'Accept-Language: en-US,en;q=0.5',
'User-Agent: Mozilla/5.0 (Windows NT 6.1; WOW64; rv:30.0) Gecko/20100101 Firefox/30.0',
'Pragma: no-cache',
'Connect: close'
);

$xml = file_get_contents($file);
$stream_options = array(
       'http' => array(
       'method'  => 'POST',
       'header'  => implode("\r\n", $headers),
       'content' => trim($xml)
    ),
);

echo "Context:".$context  = stream_context_create($stream_options);     //  sending options
echo "Response:".$response = file_get_contents($url, null, $context);   //  Response from the posting server

$serverresponse = strtolower($http_response_header['0']);

if($serverresponse==strtolower("HTTP/1.1 200 OK")) { // check success response
echo "Success";
} else {  // other response
echo "Something went wrong...";
}


} else { echo "XML file not found."; } // check file existance

?>