FacebookRestClient::post_request PHP Method

    public function post_request($method, $params)
    {
        $params['method'] = $method;
        $params['session_key'] = $this->session_key;
        $params['api_key'] = $this->api_key;
        $params['call_id'] = microtime(true);
        if ($params['call_id'] <= $this->last_call_id) {
            $params['call_id'] = $this->last_call_id + 0.001;
        }
        $this->last_call_id = $params['call_id'];
        if (!isset($params['v'])) {
            $params['v'] = '1.0';
        }
        $post_params = array();
        foreach ($params as $key => &$val) {
            if (is_array($val)) {
                $val = implode(',', $val);
            }
            $post_params[] = $key . '=' . urlencode($val);
        }
        $secret = $this->secret;
        $post_params[] = 'sig=' . Facebook::generate_sig($params, $secret);
        $post_string = implode('&', $post_params);
        if (function_exists('curl_init')) {
            // Use CURL if installed...
            $ch = curl_init();
            curl_setopt($ch, CURLOPT_URL, $this->server_addr);
            curl_setopt($ch, CURLOPT_POSTFIELDS, $post_string);
            curl_setopt($ch, CURLOPT_RETURNTRANSFER, true);
            curl_setopt($ch, CURLOPT_USERAGENT, 'Facebook API PHP5 Client 1.1 (curl) ' . phpversion());
            $result = curl_exec($ch);
            curl_close($ch);
        } else {
            // Non-CURL based version...
            $context = array('http' => array('method' => 'POST', 'header' => 'Content-type: application/x-www-form-urlencoded' . "\r\n" . 'User-Agent: Facebook API PHP5 Client 1.1 (non-curl) ' . phpversion() . "\r\n" . 'Content-length: ' . strlen($post_string), 'content' => $post_string));
            $contextid = stream_context_create($context);
            $sock = fopen($this->server_addr, 'r', false, $contextid);
            if ($sock) {
                $result = '';
                while (!feof($sock)) {
                    $result .= fgets($sock, 4096);
                }
                fclose($sock);
            }
        }
        return $result;
    }