Question

I am new in ruby,and follow the book “The Ruby Programming Language”, I am trying to learn some Socket in ruby,and the following is my simple server/client:

## server

require 'socket'

server= UDPSocket.new
server.bind('localhost', 3000)
loop do
    data,address=server.recvfrom(1024)
    server.send(data.reverse,0,address[3],address[1])  ############ My problem #########
    puts "get #{data} from #{address[3]}"
end

---

##client
require 'socket'

ds = UDPSocket.new
#ds.connect('localhost', 3000)
while line=gets
    ds.send(line.chomp, 0,'localhost', 3000)
    response,address = ds.recvfrom(1024)
    puts response
end

Note the line

server.send(data.reverse,0,address[3],address[1])

If I comment this line,it seems that the server will hold on ,and do not response to the client anymore.

I wonder why?

Does it mean that the UDPSocket must do some response to the client to continue?

Answer 1

Because you write “recvfrom” in the server side, if you comment this, it will not block, and it will continue to send data to client side. However, in real situation, the peers of communication should exchange information.