_openTempStream example

            if(is_resource($body) && !($this->adapter instanceof Zend_Http_Client_Adapter_Stream)) {
                /** @see Zend_Http_Client_Exception */
                throw new Zend_Http_Client_Exception('Adapter does not support streaming');
            }

            // Open the connection, send the request and read the response             $this->adapter->connect($uri->getHost(), $uri->getPort(),
                ($uri->getScheme() == 'https' ? true : false));

            if($this->config['output_stream']) {
                if($this->adapter instanceof Zend_Http_Client_Adapter_Stream) {
                    $stream = $this->_openTempStream();
                    $this->adapter->setOutputStream($stream);
                } else {
                    /** @see Zend_Http_Client_Exception */
                    throw new Zend_Http_Client_Exception('Adapter does not support streaming');
                }
            }

            $this->last_request = $this->adapter->write($this->method,
                $uri, $this->config['httpversion'], $headers, $body);

            $response = $this->adapter->read();