A suggestion about interfacing with C

[mockturtle <framefritti@gmail.com>]

Dear all,
I need to interface with a C library (libnl, for using Netlink in Linux).  The library provides a "socket" represented by a struct nl_sock, but the user (the library user, that is, myself) sees only a pointer to nl_sock, since the library provides constructors, destructors and everything is needed to manipulate the socket. In a sense, the user can consider the pointer just as an "opaque handler" rather than a pointer. (I must say that my first impression of the API is definitively positive). 

In Ada I would like to provide a slightly thick package that hides the C type behind a, say, Netlink_Socket type that could be a record holding the pointer to nl_sock. Note that since libnl uses said pointer as an opaque handle, I just need to store the "bitstring" representing its value, in order to pass it to the C library.

I was wandering about the best way to implement the Ada "view"  of the pointer to nl_sock.  

* I could use Interfaces.C.Pointers, but it seems me an overkill since I do not need to do pointer arithmetic.  Moreover, I would need to define a record equivalento to struct nl_sock (although maybe in my case a null record could suffice)

* I could convert it in C to a char* and then using Interfaces.C.Strings.  (A bit dirty, but not too much...)

* I could convert it to an integer... (no, definitively too dirty)

* others? 

What would you suggest?

Keep in mind that the software will run on Linux only (Netlink is specific to Linux, as long as I know) and at 99.99% only on x86 and similar.

Thank you in advance for your help

Riccardo