Here's a link to exactly what you need:


I totally forgot about 0pl - That's it! Thanks for the quick response.

a thread in the archives where Alexander explains it to me...

I wasn't able to find it, but here's my attempt:

Passing a pointer reference to 'native' is similar to the integer reference
example found here: https://software-lab.de/doc/native.html#structArg.

It becomes clearer when we think of a reference (a pointer) to a pointer
instead as a buffer of 8 bytes - sizeof(*ptr) | sizeof(long) - that
contains a pointer.

We can pass this buffer to 'native' with:

   (list NIL (8) (cons Ptr 8))

'native' then receives something like:

   (NIL (8) (35680432 . 8))

In English, I'd read this as "a buffer of 8 bytes - that we won't need to
reference again (hence NIL) - initialized to contain our pointer, literally
'long 35680432' in C."

That's a mouthful. Let's create a naive little helper function so we don't
have to think about it anymore:

   (de &ptr (P) (list NIL (8) (cons P 8)))

A bit more intuitive now:

   : (setq *N (native "libzyre.so" "zyre_create" 'N "node"))
   -> 36274819
   : (setq *N (native "libzyre.so" "zyre_destroy" NIL (&ptr *N)))
   -> NIL

Look how nicely '&ptr' pairs with the global variable naming convention ;)
not that I'd ever recommend a global variable for each node on a network...

Corrections/clarifications encouraged!


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