关闭Ruby TCPSocket客户端时关闭流(TCPSocket)

Question

我有一个Ruby TCPSocket客户端，除了我试图关闭它的时候，它工作得很好。当我在下面的代码中调用断开连接方法时，我会得到以下错误：

./smartlinc.rb:70:in `start_listen': stream closed (IOError)
    from ./smartlinc.rb:132:in `initialize'
    from ./smartlinc.rb:132:in `new'
    from ./smartlinc.rb:132:in `start_listen'
    from bot.rb:45:in `initialize'
    from bot.rb:223:in `new'
    from bot.rb:223

以下是(简化的)代码：

class Smartlinc

    def initialize
        @socket = TCPSocket.new(HOST, PORT)
    end

    def disconnect
        @socket.close
    end

    def start_listen
        # Listen on a background thread
        th = Thread.new do
            Thread.current.abort_on_exception = true

            # Listen for Ctrl-C and disconnect socket gracefully.
            Kernel.trap('INT') do 
                self.disconnect
                exit
            end

            while true
                ready = IO.select([@socket])
                readable = ready[0]
                readable.each do |soc|
                    if soc == @socket
                        buf = @socket.recv_nonblock(1024)
                        if buf.length == 0
                            puts "The socket connection is dead. Exiting."
                            exit
                        else
                            puts "Received Message"
                        end
                    end
                end # end each
            end # end while

        end # end thread
    end # end message callback

end

有什么方法可以防止或捕捉到这个错误吗？我不是套接字编程方面的专家(很明显！)，所以我们非常感谢所有的帮助。

Answer 1

您的线程位于IO.select()中，而陷阱代码却愉快地用@socket.close猛击它的门，因此您会收到一些抱怨。

不要将abort_on_exception设置为true，或者在代码中正确处理异常：

像这样的东西..。

Kernel.trap('INT') do
  @interrupted = true
  disconnect
  exit
end

...
ready = nil
begin
  ready = IO.select(...)
rescue IOError
  if @interrupted
    puts "Interrupted, we're outta here..."
    exit
  end
  # Else it was a genuine IOError caused by something else, so propagate it up..
  raise
end

...