From: Sean O'Halpin <sean.ohalpin@...>
Date: 2011-10-16T05:21:31+09:00
Subject: Re: deadlock producer consumer

On Sat, Oct 15, 2011 at 3:26 PM, rubix Rubix <aggouni2002@yahoo.fr> wrote:
> I tried simple Queue and it doesn't work too
> because I think it a circular wait, the consumer consume from a queue
> but produce new data and push them to the other queue
> the producer make the same thing too
> and i think that's why I have deadlock but I don't know how to solve the
> problem

Is this the kind of behaviour you're looking for?

require 'thread'

producer_queue = Queue.new
consumer_queue = Queue.new

def log(*a)
  STDERR.print a.inspect + "\n"
end

producer = Thread.start do
  loop do
    log :producer, :pop
    item = producer_queue.pop
    log :producer, :item, item
    item[:producer] += 1
    log :producer, :push, item
    consumer_queue.push(item)
  end
end

consumer = Thread.start do
  loop do
    log :consumer, :pop
    item = consumer_queue.pop
    log :consumer, :item, item
    item[:consumer] += 1
    log :consumer, :push, item
    producer_queue.push(item)
  end
end

# start things off
producer_queue.push({ :producer => 0, :consumer => 0})
# either will work
#consumer_queue.push({ :producer => 0, :consumer => 0})

consumer.join
producer.join


Regards,
Sean