From: Gaspard Bucher <gaspard@...>
Date: 2007-10-11T00:29:47+09:00
Subject: retain VALUE from C extension

How do I tell ruby to increment it's garbage collector if I want to
keep hold of a VALUE in a C extension.

example:

VALUE message;

static VALUE store_message(VALUE self, VALUE msg) {
  // tell ruby to retain....
  // rb_retain(msg) ?
  message = msg;
  return Qnil;
}