def csv_to_stdout(rows, cols: nil)
      CSV($stdout) { |f| csv_write0(f, rows, cols: cols) }
    end
def csv_to_stdout(rows, cols: nil)
      CSV($stdout) { |f| csv_write0(f, rows, cols: cols) }
    end
Write +rows+ to $stdout as a csv. Similar to csv_write.