import lyng.buffer
import lyng.io.net

val server = Net.tcpListen(0, "127.0.0.1")
val port = server.localAddress().port
val accepted = launch {
    val client = server.accept()
    val line = (client.read(4) as Buffer).decodeUtf8()
    client.writeUtf8("echo:" + line)
    client.flush()
    client.close()
    server.close()
    line
}

val socket = Net.tcpConnect("127.0.0.1", port)
socket.writeUtf8("ping")
socket.flush()
val reply = (socket.read(16) as Buffer).decodeUtf8()
socket.close()
println("${accepted.await()}: $reply")