TelnetGqrx.scala

// cf. https://stackoverflow.com/questions/13343260/telnet-like-connection-to-server-in-scala
class Connector(socket: java.net.Socket, handler: String => Unit) {
  private val out = new java.io.PrintStream(socket.getOutputStream)
  private val in  = new java.io.BufferedReader(new java.io.InputStreamReader(socket.getInputStream))

  private val receiver = new Thread {
    override def run(): Unit = {
//       var done = false
//       while (!done) {
//         val n = in.read()
//         if(n < 0)
//           done = true
//         else
//           handler(n.toChar)
//       }
      var msg = in.readLine()
      while (msg != null) {
        handler(msg)
        msg = in.readLine()
      }
    }
    start()
  }

  def print(msg: String): Unit = out.println(msg)

  def close(): Unit = {
    in .close()
    out.close()
  }
}

// cf. http://gqrx.dk/doc/remote-control
val socket = new java.net.Socket("127.0.0.1", 7356)  // default port of gqrx

val c = new Connector(socket, println)

c.print("F 95200000")
c.print("l STRENGTH")
c.print("F 95300000")
c.print("l STRENGTH")
c.print("F 95400000")
c.print("l STRENGTH")

c.print("U RECORD 1")
c.print("U RECORD 0")

// c.close() -- that seems to hang