Get Header from URL

headers.php

<?php
/**
 * To execute this: php headers.php http.//url_to_check.com header
 */
$strURL = isset($argv[1]) ? $argv[1] : NULL;
$headerFind = isset($argv[2]) ? $argv[2] : NULL;

$resCurl = curl_init();

// Set URL and other appropriate options.
curl_setopt($resCurl, CURLOPT_URL, $strURL);
curl_setopt($resCurl, CURLOPT_HEADER, true);
curl_setopt($resCurl, CURLOPT_NOBODY, true);
curl_setopt($resCurl, CURLOPT_RETURNTRANSFER, true);
curl_setopt($resCurl, CURLOPT_FOLLOWLOCATION, true);

// Get the headers.
$strHeaders = curl_exec($resCurl);

// Close cURL.
curl_close($resCurl);

if (isset($headerFind)) {
  $strHeaders2 = explode("\n", str_replace("\r", '', $strHeaders));
  $headers = array();
  foreach ($strHeaders2 as $header) {
    $value = explode(': ', $header);
    if (isset ($value[0]) && isset($value[1])) {
      $headers[$value[0]] = $value[1];
    }
  }
  echo isset($headers[$headerFind]) ? $headers[$headerFind] : 'Header not found';
}
else {
  echo $strHeaders;
}