This Gist adds f4stdev and rudimentary POST request capability. -- Simple GET & POST requests in PHP.

http.php

<?php

/*
 *  Simple HttpRequest example using PHP
 *  tom slankard
 *  POST capability: Techplex Engineer
 *  https://gist.github.com/twslankard/989974
 *  http://stackoverflow.com/a/20621965/429544
 */

class HttpRequest {

  public $url = null;
  public $method = 'GET';
  public $body = null;
  public $headers = Array();
  public $allow_redirect = true;

  private $url_info = null;
  private $host_name = null; 
  private $host_ip = null;
  private $response_body = null;
  private $response_headers = Array();
  private $response_code = null;
  private $response_message = null;
  private $port = null;
  private $verbose = true;
  private $raw_post_data = "";

  public function __construct($url, $method = 'GET') {

    $this->url = $url;
    $this->method = $method;

    //  parse url
    $this->url_info = parse_url($url);
    $this->host_name = $this->url_info['host'];
    $this->host_ip = gethostbyname($this->host_name);

    //  get port number given the scheme
    if(!isset($this->url_info['port'])) {
      if($this->url_info['scheme'] == "http")
        $this->port = 80;
      else if($this->url_info['scheme'] == "https")
        $this->port = 443;
    } else {
      $this->port = $this->url_info['port'];
    }

    //  add default headers
    $this->headers["Host"] = "$this->host_name";
    $this->headers["Connection"] = "close";

  }
  public function setRawPostData($data)
  {
    if ($this->method != "POST") {
      return false;
    }
    $this->raw_post_data = $data;
  }

  private function constructRequest() {
    $path = "/";
    if(isset($this->url_info['path']))
      $path = $this->url_info['path'];

    $req = "$this->method $path HTTP/1.1\r\n";
    foreach($this->headers as $header => $value) {
      $req .= "$header: $value\r\n";
    }
    $req .= "Content-Length: ".strlen($this->raw_post_data)."\r\n";
    $req .= "\r\n";
    $req .= $this->raw_post_data;

    return "$req\r\n";
  }

  ///  reads a line from a file
  function readLine($fp)
  {
    $line = "";

    while (!feof($fp)) {
      $line .= fgets($fp, 2048);
      if (substr($line, -1) == "\n") {
        return rtrim($line, "\r\n");
      }
    }
    return $line;
  }

  public function send() {

    $fp = fsockopen($this->host_ip, $this->port);
    if (! $fp) return False;

    //  construct request
    $request = $this->constructRequest();

    //  write request to socket
    fwrite($fp, $request);

    //  read the status line
    $line = $this->readline($fp);
    $status = explode(" ", $line);

    //  make sure the HTTP version is valid
    if(!isset($status[0]) || !preg_match("/^HTTP\/\d+\.?\d*/", $status[0]))
      die("Couldn't get HTTP version from response.");

    //  get the response code
    if(!isset($status[1]))
      die("Couldn't get HTTP response code from response.");
    else $this->response_code = $status[1];

    //  get the reason, e.g. "not found"
    if(!isset($status[2]))
      die("Couldn't get HTTP response reason from response.");
    else $this->response_reason = $status[2];

    //  read the headers
    do {
      $line = $this->readLine($fp);
      if($line != "") {
        $header = explode(":", $line);

        $this->response_headers[$header[0]] = ltrim($header[1]);
      }
    } while(!feof($fp) && $line != "");

    //  read the body
    $this->response_body = "";
    do {
      $line = $this->readLine($fp); {
      if($line)
        $this->response_body .= "$line\n";
      }
    } while(!feof($fp));

    //  close the connection
    fclose($fp);

    return TRUE;
  }

  public function getStatus() {
    return $this->response_code;
  }

  public function getHeaders() {
    return $this->response_headers;
  }

  public function getResponseBody() {
    return $this->response_body;
  }

}

index.php

<?php

include_once("http.php");

//Sample GET Request
$req = new HttpRequest("http://httpbin.org/get", "GET");
$req->headers["Connection"] = "close";
$req->send() or die("Couldn't send!");
echo( $req->getResponseBody() );

//Sample POST Request
$data = array(
	'key1' => 'value1',
	'key2' => 'value2',
	'key3' => 'value3',
);

$request = new HTTPRequest("http://httpbin.org/post", 'POST');
$request->setRawPostData(http_build_query($data)); //ke1=value1&key2=value2&key3=value3
$req->send() or die("Couldn't send!");
echo( $req->getResponseBody() );