From: Ashley Moran <work@...>
Date: 2006-04-23T21:21:57+09:00
Subject: Re: How do threads and join work?


On Apr 23, 2006, at 1:03 pm, Pat Maddox wrote:
> Well this is all because I need to interact with a remote server that
> sends asyncrhonous messages.  I suppose the most common server that's
> similar is an IRC server.  You connect to the server, and then just
> wait while it pumps out messages to you.  The way I've implemented
> this in other languages is to create a new thread which simply has an
> infinite loop (checking a control condition, such as @connected) that
> reads data from a socket.  So in cases like this, the read call would
> block until some data comes through the socket.  Then it parses the
> text and the loop continues.  I'm trying to do the same thing with
> Ruby.
>
> Pat
>

Ahh... I thought this was a newbie question hence patronising intial  
reply...

One possibility is the Queue object in the threads library:

   require 'thread'

   messages = Queue.new

   server = Thread.new do
     print "Server started\n"
     10.times do |i|
       sleep rand(5)
       messages << "Message #{i}"
     end
     messages << "Disconnect"
     print "Server finished\n"
   end

   client = Thread.new do
     while true
       message = messages.pop # blocks here
       puts "Received: #{message.inspect}"
       if message == "Disconnect"
         puts "Disconnecting from server"
         break
       end
     end
   end

   puts "Before join"
   client.join
   puts "After join"

   puts "Program finished"

This is based on the example in the RDoc

There's a load of different ways to synchronise data.  My boss has my  
copy of the pickaxe but they are all cross referenced.  Start with  
Monitor - it's what I used last, although that wasn't for a client- 
server application but for aggregating data from a group of  
individual threads.

Is this any help?  (at last!)

Regards
Ashley