gistfile1.scala

reset {
  val w1 = shift { (cont: PrintWriter => Unit) =>
    using(new PrintWriter("col1.txt"))(cont)
  }
  val w2 = shift { (cont: PrintWriter => Unit) =>
    using(new PrintWriter("col2.txt"))(cont)
  }
 
  Console.err.println("A")
  Source.stdin.getLines().map(_.split("\t")).foreach {
    case Array(col1, col2, _*) =>
      w1.println(col1)
      w2.println(col2)
    case Array(col1) => w1.println(col1)
  }
  Console.err.println("B")
}