; OpenTCPStream Example
; ---------------------

; This program is server AND client at once: it listens on a
; port, then connects to itself over the loopback address.

port=4002

server=CreateTCPServer(port)
If server=0 Then
    Print "Could not listen on port "+port+" (it may be in use)"
Else
    Print "Server: listening on port "+port

    ; OpenTCPStream connects to a host and port and returns a
    ; stream handle, or 0 on failure. The host can also be a
    ; name such as "www.blitzbasic.com".
    client=OpenTCPStream("127.0.0.1",port)
    If client=0 Then
        Print "Client: could not connect"
    Else
        Print "Client: connected to 127.0.0.1:"+port

        ; The server accepts the incoming connection - poll briefly,
        ; because AcceptTCPStream returns 0 until one has arrived
        accepted=0
        For try=1 To 100
            accepted=AcceptTCPStream(server)
            If accepted<>0 Then Exit
            Delay 10
        Next

        If accepted=0 Then
            Print "Server: no connection arrived"
        Else
            Print "Server: connection accepted"

            ; The opened stream reads and writes just like a file
            WriteLine client,"Ping from the client"
            Print "Client: sent 'Ping from the client'"
            Print "Server: received '"+ReadLine$(accepted)+"'"
            WriteLine accepted,"Pong from the server"
            Print "Client: received '"+ReadLine$(client)+"'"

            CloseTCPStream accepted
        EndIf
        CloseTCPStream client
    EndIf
    CloseTCPServer server
    Print "Server: closed"
EndIf

Print ""
Print "Press any key to close the example"
WaitKey

End