Hi Matj P,

The Ruby class you specify (as a Ruby "VALUE") defines the class of the 
object that is created. This object then carries around the pointer you 
supplied it, which can be extracted at a later time. For me, the Ruby 
class comes from the alloc call for the object, but you can create a 
class with "rb_define_class" as well.

At this point I would definitely recommend writing a small, detached 
program, and experimenting with it there, because honestly, some of this 
stuff is *really* hard, and you can learn a lot from this 
experimentation (this is what I did initially, reluctantly, and it 
helped enormously). The book I mentioned before is useful, and has lots 
of good examples, but failing that, Google searches with terms such as 
"Ruby embed" or "Ruby extend" might give you something close. As a last 
resort, the two ruby.h headers are good- search for the text of what you 
are after and sometimes you turn up useful functions. :)

Garth

On 20/01/12 03:39, Matj P. wrote:
> I quite understand, what you wrote. When I wrap structure I have to
> specify a Ruby class. If I understand well this Ruby class will wrap my
> C struct so it should have same signature like my struct? How is it
> inicialized?
>