From: Florian Gross <flgr@...>
Date: 2004-08-27T04:05:35+09:00
Subject: Re: Dereferencing pointers returned by syscall

tad.bochan@bnpparibas.com wrote:

> Hi,

Moin!

> I'm using 'syscall' in ruby to access the 'mmap'  function in Unix (HPUX),
> to try to read/write a memory-mapped file.
> The 'mmap' function returns a pointer to the mapped file.
> I can't figure out how I am supposed to be able to use
> this pointer  to access the data from ruby.

Have a look at Ruby/DL which is part of Standard Ruby. With 
DL::Importable you can create a struct like this:

Foo = struct [
   "long foo",
   "int bar",
   ...
]

And later you can do Foo.new(DL::PtrData.new(ptr)).

Regards,
Florian Gross