resource conversation()
  op server(int n) returns cap (string[10] s) c
  process client [ i = 1 to 5 ] {
    string[10] s[20] = ([20]" ")

    cap (string[10] s) c
    c = server(20)
    for [ i = 1 to 20 ] { send c(s[i]) }

  }
  proc server(n) returns c  {
    op line(string[10] s)
    c = line
    reply   # pass back capability for line
    for [ i = 1 to n ] {
      string[10] s
      receive line(s)
      # do something with s, e.g., print it
    }
  }
end