From: "Richard W.M. Jones" <rich@annexia.org>
To: "Laurent Thévenoux" <laurent.thevenoux@inria.fr>
Cc: caml-list@inria.fr
Subject: Re: [Caml-list] Interfacing C with OCaml and file descriptors
Date: Fri, 13 Oct 2017 22:37:41 +0100 [thread overview]
Message-ID: <20171013213741.ke5ptnxrq2w3n6oq@annexia.org> (raw)
In-Reply-To: <3380AF33-0E0F-46E9-BF03-E61B65E6B838@inria.fr>
On Fri, Oct 13, 2017 at 12:57:33PM +0200, Laurent Thévenoux wrote:
> Hi,
>
> I have a naive question about file descriptors and C interface (when interfacing C with OCaml).
Firstly, you're confused about the difference between 'FILE *' and a
file descriptor. They are not the same thing at all. Read some basic
Unix texts about the difference.
Once you've sorted that out, it turns out that you can (currently)
cast a Unix.file_descr from OCaml directly into a C int file
descriptor using Int_val:
int fd = Int_val (fdv);
read (fd, buf, len);
It would be really nice if there was an official C function defined by
OCaml to do this in a portable and future-proof way!
Rich.
next prev parent reply other threads:[~2017-10-13 21:37 UTC|newest]
Thread overview: 8+ messages / expand[flat|nested] mbox.gz Atom feed top
2017-10-13 10:57 Laurent Thévenoux
2017-10-13 11:10 ` Nicolás Ojeda Bär
2017-10-13 21:37 ` Richard W.M. Jones [this message]
2017-10-13 22:42 ` David Allsopp
2017-10-14 6:10 ` Richard W.M. Jones
2017-10-14 15:18 ` Malcolm Matalka
2017-10-14 15:54 ` Thierry Martinez
2017-10-16 6:46 ` Laurent Thévenoux
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