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Date: -- (:)
From: Dmitry Bely <dbely@m...>
Subject: Re: [Caml-list] camlidl - character arrays?
Brian Naylor <bwv211mail@yahoo.com> writes:

> I am trying to use CamlIDL for a C function like the following:
>
>     int foo (unsigned char [16]);
>
> If I write my CamlIDL file like this:
>
>     int foo ([in,string] unsigned char s [16]);
>
> The code does a check like this:
>
>     if (string_length(_v_s) >= 16) invalid argument("foo");
>
> The problem is that this is NOT a null-terminated string - it is exactly 16
> bytes of data.

You have two options here:

1. Don't use "string" attribute and pass OCaml character array (not string)
to your function or
2. Declare it as
     int foo ([string] unsigned char s[17]);
As C arrays are passed by the pointer, your C function will never know that
the trailing '\0' is there.

Dmitry Bely


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