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From: Marek Kubica <marek@xivilization.net>
To: caml-list@inria.fr
Subject: [Caml-list] C interop: Return values in parameters
Date: Sun, 30 Dec 2012 14:08:23 +0100	[thread overview]
Message-ID: <20121230140823.20f39bcd@xivilization.net> (raw)

Hi,

I am trying to wrap a C library in OCaml but I don't know how to do
this particular thing:

I have a library that looks roughly like this:

int function(void** ptr);

So I get an int as return value to show whether the function succeeded
and it *sets* the ptr.

void* ptr;
function(&ptr);
// ptr is different now

How can I wrap such a function in OCaml? When I call my OCaml wrapper

let retval = function ptr in
    ...

the pointer does not get updated. Is there a function in the C API to
force OCaml to update the values?

regards,
Marek

             reply	other threads:[~2012-12-30 13:09 UTC|newest]

Thread overview: 5+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2012-12-30 13:08 Marek Kubica [this message]
2012-12-30 14:01 ` Török Edwin
2012-12-30 14:19   ` Marek Kubica
2012-12-30 14:36     ` Gabriel Scherer
2012-12-31  1:48       ` Marek Kubica

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