PHP에서 HTTP 요청을 보내는 여러 가지 방법에 대한 자세한 설명

No. Guzzle can use any HTTP handler to send requests. This means that Guzzle can be used with cURL, 
PHP's stream wrapper, sockets, and non-blocking libraries like React. You just need to configure an HTTP handler to use a different method of sending requests.

<?php
/**
 * Created by PhpStorm.
 * User: tanteng
 * Date: 2017/7/22
 * Time: 13:48
 */
function post($url, $data)
{
  $postdata = http_build_query(
    $data
  );

  $opts = array(&#39;http&#39; =>
           array(
             &#39;method&#39; => &#39;POST&#39;,
             &#39;header&#39; => &#39;Content-type: application/x-www-form-urlencoded&#39;,
             &#39;content&#39; => $postdata
           )
  );
  $context = stream_context_create($opts);
  $result = file_get_contents($url, false, $context);
  return $result;
}

<?php
$fp = fsockopen("www.example.com", 80, $errno, $errstr, 30);
if (!$fp) {
  echo "$errstr ($errno)<br />\n";
} else {
  $out = "GET / HTTP/1.1\r\n";
  $out .= "Host: www.example.com\r\n";
  $out .= "Connection: Close\r\n\r\n";
  fwrite($fp, $out);
  while (!feof($fp)) {
    echo fgets($fp, 128);
  }
  fclose($fp);
}
?>