From: Andre' <andre_NOSPAM@...>
Date: 2004-08-11T23:35:57+09:00
Subject: Thread takeover

Strangely, I'm having the problem that one thread is taking over the whole  
process.

Imagine this main file:

Thread.new {
         class Main
                 def initialize
                         while true
                                 print 1
                         end
                 end
         end
         m = Main.new
}
Thread.new {
         require 'p.rb'
         m = Main.new
}
while true; end

It has two threads: one is printing 1 all the time in the screen. I have a  
second - external - that is exactly like the first, but it prints 2. The  
'p.rb' is this one:

class Main
         def initialize
                 while true
                         print 2
                 end
         end
end

It acts as expected. (11112222221111111222222)

But if I add the line "m = Main.new" at the end of 'p.rb', the thread  
seems to take over! (22222222222222222222222222222222222)

Since this 'p.rb' is some external file the users will input, I can't tell  
what it'll be on it, so I can't avoid that a malicious code takes over my  
program! Or can I?

-- 
(c) Andre' - All rights reseved - 2004