hi all! i’ve been on elixir’s irc but can’t really get anything working. so i decided to join the forum.
i’m from the crystal lang repo, i’m very new to elixir but i do like it.

i’m having trouble with my tcp server, and read and send messages from the tcp stream. i’m using this code from the clientside:

it sends a unisgned 32 bit, that is the length of the message (clientside) i need to read this from my elixir tcp server:

defmodule Server do
  def start(port) do
    tcp_options = [:binary, {:packet, 0}, {:active, false}]
    {:ok, socket} = :gen_tcp.listen(port, tcp_options)
    IO.puts "Started Master Server on port: #{port}"
    listen(socket)
  end

  def listen(socket) do
    {:ok, conn} = :gen_tcp.accept(socket)
    spawn(fn -> recv(conn) end)
    listen(socket)
  end

  def recv(conn) do
    IO.puts "New connection: #{inspect(conn)}"
    test_message = "hello clarice"
    #:gen_tcp.send(conn, Integer.to_string( byte_size(test_message)) )
    :gen_tcp.send(conn, test_message)
    :gen_tcp.send(conn, test_message)
    case :gen_tcp.recv(conn, 0) do
      {:ok, data} ->
       :gen_tcp.send(conn, data)
       IO.puts "Received: #{data}"
       recv(conn)
      {:error, :closed} -> :ok
        IO.puts "#{inspect(conn)} has disconnected"
    end
  end
end

Server.start(1234)

the problem I have is, my tcp option :packet, only goes up to 4. i need it to be 32, but it won’t let me. i also tried to send the the byte_size befoe the message (line 18 commented out) but that doesn’t work either. i’m not sure what i’m doing wrong, or how i can read a unsigned 32 bit flag from a tcp stream.

thank you in advance