From: Tony Arcieri <tony.arcieri@...>
Date: 2011-02-07T04:02:02+09:00
Subject: Re: C extension: How to check if a VALUE is still alive (not being GC'ed)?

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On Sat, Feb 5, 2011 at 4:02 PM, I=F1aki Baz Castillo <ibc@aliax.net> wrote:

> The problem is that the VALUE could be GC'ed (or being marked for so)
> if the programmer assigns it to "nil" before the callback is executed,
> so we get a coredump.
>
> So when the callback is executed I need to check that the given VALUE
> is still alive (not GC'ed neither marked for being GC'ed). How can I
> inspect that? (I mean in C).


How is rb_gc_mark() insufficient here? Marking prevents objects from being
GCed... you seem to be suggesting it's the other way around.

If you mark all VALUEs your C extension is internally referencing in your C
extension's "mark" function it will prevent them from being garbage
collected.

As Peter said though, if you use rb_iv_set, you get this behavior for free
as Ruby automatically marks instance variables for you.

--=20
Tony Arcieri
Medioh! Kudelski

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