FnStream example

/** * Close both the remote stream and buffer stream */
    public function close(): void
    {
        $this->remoteStream->close();
        $this->stream->close();
    }

    private function cacheEntireStream(): int
    {
        $target = new FnStream(['write' => 'strlen']);
        Utils::copyToStream($this, $target);

        return $this->tell();
    }
}