From: Sam Duncan <sduncan@...>
Date: 2011-10-11T07:39:05+09:00
Subject: Re: scheduler and thread

On 11/10/11 11:20, lover ruby wrote:
> Hi
> I want to make a scheduler like this.
>
> module Timer
>    def Timer.repeat_every(interval)
>      Thread.new do
>        loop do
>          start_time = Time.now
>          yield
>          elapsed = Time.now - start_time
>          sleep([interval - elapsed, 0].max)
>        end
>      end.join
>    end
> end
>
> Timer.repeat_every(5) do
>   puts Time.now.to_i
> end
>
> puts "Doing other stuff..."
> ---------------------------------------------------
> But it never prints out "Doing other stuff..."
>
> How can I make it print out like
> "Doing other stuff..."
> 1318284723
> 1318284728
> 1318284733
>
> Thanks
Try this;

module Timer

   @timer = nil

   def Timer.repeat_every(interval)
     @timer = Thread.new do
       loop do
         start_time = Time.now
         yield
         elapsed = Time.now - start_time
         sleep([interval - elapsed, 0].max)
       end
     end
   end

   def Timer.stop
     unless @timer.nil?
       @timer.kill
       @timer.join(1) # don't hang forever
       @timer = nil
     end
   end

end

Timer.repeat_every(5) do
  puts Time.now.to_i
end

puts "Doing other stuff..."
sleep 10
puts "Stopping timer"
Timer.stop


As far as I can tell your execution is hanging on the join which will never return as the timer thread is in an infinite loop =]

Hope that helps
Sam