[Caml-list] Interfacing C with OCaml and file descriptors

["Laurent Thévenoux" <laurent.thevenoux@inria.fr>]

Hi,

I have a naive question about file descriptors and C interface (when interfacing C with OCaml).

For instance, a file.ml file which looks like:


external my_c_interface : out_channel -> int = c_function


where c_function writes something to a file and return the number of written char.
The c_function takes a FILE* file descriptor, as for example:


CAMLprim value c_function (value channel)
{
	CAMLparam1 (channel);
	FILE* fd = ???;
	CAMLreturn (Val_int (call_to_c_func (fd)));
}


So, if possible, how to convert the ‘value channel’ to a ‘FILE*’?

Thanks for your help,
Laurent