<?php
$key = '/e8SE81Dtn4l/NwlIMLvXHFutoXjilTk';
$fp = stream_socket_client('tcp://localhost:30033', $errno, $errstr, 30, STREAM_CLIENT_CONNECT);
if (!$fp) {
    die('connection failed');
}

fwrite($fp, $key);

$size = intval(5245060);
$pack = 4096;

$datas = '';
for($seek = 0;$seek < $size;)
{
    $rest = $size-$seek;
    $pack = $rest < $pack ? $rest : $pack;
    $data = fread($fp, $rest < $pack ? $rest : $pack);
    $seek = $seek+$pack;
    $datas .= $data;
}

echo strlen($datas);