From: Mage <mage@...>
Date: 2006-01-25T20:41:20+09:00
Subject: threading sync

          Hello,

I was thinking of writing my first threaded app in Ruby. One thread 
should fetch data from the database, another should write it to a file.

I would like to use an array, which has hash elements. I append new 
elements to the end, and I write to the file from the beginning (FIFO).

My question is that do I really need mutex? Is appending a hash to the 
end of an array atomic, or not? How can I know which method is atomic?

       Mage