From: Jamis Buck <jgb3@...>
Date: 2004-10-29T03:51:07+09:00
Subject: Re: Dereferencing PtrData in Ruby/DL

Carl Youngblood wrote:
> Hello.  I have allocated a pointer using DL.malloc:
> 
> window = DL.malloc(DL.sizeof('P'))
> 
> At times in my code I have to pass a pointer this pointer, and at
> other times I have to pass in the value of the pointer itself.  Does
> anybody know how to dereference PtrData?
> 
> Thanks,
> Carl Youngblood

Carl,

I believe that if you have a variable 'x' that is a DL::PtrData 
instance, you can do:

   y = x.ref #-> get pointer to the pointer x
   z = y.ptr #-> obtain the value that y points to, as a PtrData
   assert x == z

I only tried this in IRB, but it appears to work as I described it.

- Jamis

-- 
Jamis Buck
jgb3@email.byu.edu
http://www.jamisbuck.org/jamis