Here's a simple script for sending messages back and forth between a server and client.  At this point, the code is fairly rough because once it enters the while loop, it doesn't stop but it can be modified and fixed.  Enjoy.

<?php
//The Server
error_reporting(E_ALL);
$address = "127.0.0.1";
$port = "10000";
 

/* create a socket in the AF_INET family, using SOCK_STREAM for TCP connection */
$mysock = socket_create(AF_INET, SOCK_STREAM, SOL_TCP);

socket_bind($mysock, $address, $port);

socket_listen($mysock, 5);

$client = socket_accept($mysock);

echo "Server started, accepting connections...\n";
 

$i = 0;
while (true == true)
{
    $i++;
    echo "Sending $i to client.\n";
    socket_write($client, $i, strlen($i));
    
    $input = socket_read($client, 2048);
    echo "Response from client is: $input\n";
    sleep(5);
}

echo "Closing sockets...";
socket_close($client);

socket_close($mysock);

?> 

<?php
//The Client
error_reporting(E_ALL);

$address = "127.0.0.1";
$port = 10000;

/* Create a TCP/IP socket. */
$socket = socket_create(AF_INET, SOCK_STREAM, SOL_TCP);
if ($socket === false) {
    echo "socket_create() failed: reason: " . socket_strerror(socket_last_error()) . "\n";
} else {
    echo "socket successfully created.\n";
}

echo "Attempting to connect to '$address' on port '$port'...";
$result = socket_connect($socket, $address, $port);
if ($result === false) {
    echo "socket_connect() failed.\nReason: ($result) " . socket_strerror(socket_last_error($socket)) . "\n";
} else {
    echo "successfully connected to $address.\n";
}

$i = 0;
while (true == true)
{
    $i++;
    echo "Sending $i to server.\n";
    socket_write($socket, $i, strlen($i));
    
    $input = socket_read($socket, 2048);
    echo "Response from server is: $input\n";
    sleep(5);
}

echo "Closing socket...";
socket_close($socket);
?>