Question

how can this be done in PHP

curl -I http://www.google.com | grep "Server:"

and is it possible to just echo OS like Linux Or windows of site , like web server is echoed using curl

My Try

<?
$ch = curl_init();
curl_setopt ($ch, CURLOPT_URL,"http://google.com");
curl_setopt ($ch, CURLOPT_HEADER, 1);
$data = curl_exec ($ch);
curl_close ($ch);
echo $data  ;

?>

Answer 1

<?php
// create a new cURL resource                                                                                                                                
$ch = curl_init();

// set URL and other appropriate options                                                                                                                     
curl_setopt($ch, CURLOPT_URL, "http://www.google.com/");
curl_setopt($ch, CURLOPT_HEADER, true);
curl_setopt($ch, CURLOPT_RETURNTRANSFER, true);

// grab URL and pass it to the browser                                                                                                                       
$result = curl_exec($ch);

/* Curl returns multiple headers, if the last action required multiple                                                                                       
 * requests, e.g. when doing Digest authentication. Only parse the                                                                                           
 * headers of the latest response. */
preg_match_all('/(^|\r\n\r\n)(HTTP\/)/', $result, $matches, PREG_OFFSET_CAPTURE);
$startOfHeaders = $matches[2][count($matches[2]) - 1][1];
$endOfHeaders = strpos($result, "\r\n\r\n", $startOfHeaders);
$headers = substr($result, $startOfHeaders, $endOfHeaders - $startOfHeaders);
$headers = preg_split("/\r?\n/", $headers);
foreach ($headers as $headerLine) {
  if (preg_match('|^Server:\s+(.+)|', $headerLine, $m)) {
    var_dump($m[1]);
  }
}

// close cURL resource, and free up system resources                                                                                                         
curl_close($ch);

Basically this is an extract from the Horde_Http library. Specifically the Curl request and the Curl response handlers.

It is somewhat more complex than what you did with your “grep” command but it looked as though you want to analyse the response headers. That is why I left the somewhat more complex header analysis in the code.