class Net::POP3Command

def list
  critical {
    getok 'LIST'
    list = []
    @socket.each_list_item do |line|
      m = /\A(\d+)[ \t]+(\d+)/.match(line) or
              raise POPBadResponse, "bad response: #{line}"
      list.push  [m[1].to_i, m[2].to_i]
    end
    return list
  }
end