Socket issue?

Question

.NET

I want to implement the following functionality in a client-server application:
the client cools down the data to the server, and the server immediately after receiving the data transfers the number of bytes received to the client.

Server:

using (SocketEx socket = new SocketEx((IntPtr)state))<br>
            {<br>
                byte[] data = socket.Receive();<br>
                socket.Send(BitConverter.GetBytes(data.Length));               <br>
            }<br>

Customer:

public int Send(byte[] data)<br>
        {<br>
            int count = socket.Send(data);<br>
            byte[] response = socket.Receive();<br>
            if (response != null && response.Length == 4)<br>
            {<br>
                return BitConverter.ToInt32(response, 0);<br>
            }<br>
            return -1;<br>
        }<br>

TCP protocol, sockets from the ws2_32 standard library (regular, not WSA).
And the code on the client
is socket.Receive();
does not read the server response (recv returns -1), WSA error is written 10053 - the connection is broken. Although debugging on the server, the send method says that it sent 4 bytes.

Actually the question is how to correctly implement the server's response to the client? Is it possible to write to the same socket from which I read the data?

In theory, the recv method blocks the execution thread and must wait for the data to appear. But why doesn't it wait?