PHP TCP Socket Server - esp32

Question

I want to create a TCP socket using PHP code that can handle a large number of clients. In fact, my clients are network modules that want to connect to the server and have a two-way connection.

I have a few goals in mind:

Display a list of connected clients. Ability to send messages to a specific client through an HTML page. Ability to connect multiple clients simultaneously (in this case, I mean 10). I have a shared host, and I run all the server code on it. This host doesn't provide console access, so I have no idea how to use ready-made libraries like ReactPHP.

Currently, I have only managed to create a list of connected clients. Here is the code for that:

<?php
error_reporting(E_ALL);

$host = '0.0.0.0';
$port = 8085;

$clients = [];
$onlineUsersFile = 'online_users.json';

$server = stream_socket_server("tcp://$host:$port", $errno, $errstr);

if (!$server) {
die("Error: $errstr ($errno)\n");
}

echo "Server started on $host:$port\n";

while (true) {
$read = $clients;
$read[] = $server;

if (!stream_select($read, $write, $except, 1)) {
    // Check every 1 second for changes in connections
    continue;
}

if (in_array($server, $read)) {
    $newClient = stream_socket_accept($server);
    socket_set_blocking($newClient, 0);
    $clients[] = $newClient;
    $data = "Welcome to the chat room!\n";
    stream_socket_sendto($newClient, $data);
    echo "New client connected\n";
    broadcastToAll($clients, "New client connected\n");
    $key = array_search($server, $read);
    unset($read[$key]);
}

foreach ($read as $key => $client) {
    stream_set_timeout($client, 1);
    $data = fread($client, 1024);
    if ($data === false || feof($client)) {
        fclose($client);
        unset($clients[$key]);
        echo "Client disconnected\n";
        broadcastToAll($clients, "Client disconnected\n");
        continue;
    }
    if ($data != '') {
        broadcast($client, $data, $clients);
    }
}
updateOnlineUsers($clients, $onlineUsersFile);
}

function broadcast($sender, $message, $clients)
{
foreach ($clients as $client) {
    if ($client !== $sender) {
        stream_socket_sendto($client, $message);
    }
}
}

function broadcastToAll($clients, $message)
{
foreach ($clients as $client) {
    stream_socket_sendto($client, $message);
}
}

function updateOnlineUsers($clients, $file)
{
$onlineUsers = [];
foreach ($clients as $client) {
    $address = stream_socket_get_name($client, true);
    $onlineUsers[] = $address;
}
file_put_contents($file, json_encode($onlineUsers));
}
     $onlineUsers[] = $address;
    }
    file_put_contents($file, json_encode($onlineUsers));
}

Ability to send messages to a specific client through an HTML page.