在gets()中从Ruby中的TCP套接字恢复

我正在读取TCP套接字上的输入行,类似于:

class Bla  
  def getcmd
    @sock.gets unless @sock.closed?
  end

  def start     
    srv = TCPServer.new(5000)
    @sock = srv.accept
    while ! @sock.closed?
      ans = getcmd
    end
  end
end

如果端点在getline()运行时终止连接,则gets()挂起.

我该如何解决这个问题？是否有必要进行非阻塞或定时I/O？

您可以使用select来查看是否可以安全地从套接字获取,请参阅以下使用此技术实现TCPServer.

require 'socket'

host, port = 'localhost', 7000

TCPServer.open(host, port) do |server|
  while client = server.accept
    readfds = true
    got = nil
    begin
      readfds, writefds, exceptfds = select([client], nil, nil, 0.1)
      p :r => readfds, :w => writefds, :e => exceptfds

      if readfds
        got = client.gets 
        p got
      end
    end while got
  end
end

这里是一个试图打破服务器的客户端:

require 'socket'

host, port = 'localhost', 7000

TCPSocket.open(host, port) do |socket|
  socket.puts "Hey there"
  socket.write 'he'
  socket.flush
  socket.close
end