Hi,
I'm implementing Ruby bindings for a C library and I'm encountering some
problems related to the garbage collector, my objects are claimed too
early.

Here's the ruby code:

o.some_meth.notifier do |r|
   do_stuff_with(r)
end

In the C library, functions are processed asynchronously, so everything
is managed with intermediate Result objects.

"some_meth" will instantiate a new "Result" object. Using this Result
object, the caller can wait for the function to succeed, he can register
callbacks etc.

The Result objects notifier method registers a callback - its called
when "some_meth" finishes, which can take some time ;)
This callback might be called more than once.

In my test script, I made sure the handler is called continously.
By calling GC.start in the handler, I found out that the GC is claiming
the Result object early, since there are no objects that are marking it.

The only object that's referencing the Result object is the block at
this time, and I guess it doesn't actually mark the object :)

I know I can work around this by using rb_global_variable() to tell the
GC not to claim the object, but this kinda sucks since the object will
never be freed :(

So, my question is: how do I prevent the Result object from being
claimed by the GC without using rb_global_variable's?

What are common workarounds for these types of problems?
Is there any online documentation about the topic (besides README.EXT
and the Pickaxe's section on Extending Ruby)?

Thanks in advance.

-- 
Regards,
Tilman