From owner-freebsd-hackers@FreeBSD.ORG  Sun Mar  5 18:41:50 2006
Return-Path: <owner-freebsd-hackers@FreeBSD.ORG>
X-Original-To: freebsd-hackers@freebsd.org
Delivered-To: freebsd-hackers@freebsd.org
Received: from mx1.FreeBSD.org (mx1.freebsd.org [216.136.204.125])
	by hub.freebsd.org (Postfix) with ESMTP id 1A00F16A420
	for <freebsd-hackers@freebsd.org>; Sun,  5 Mar 2006 18:41:50 +0000 (GMT)
	(envelope-from pranav.sawargaonkar@gmail.com)
Received: from wproxy.gmail.com (wproxy.gmail.com [64.233.184.195])
	by mx1.FreeBSD.org (Postfix) with ESMTP id 55D9B43D45
	for <freebsd-hackers@freebsd.org>; Sun,  5 Mar 2006 18:41:49 +0000 (GMT)
	(envelope-from pranav.sawargaonkar@gmail.com)
Received: by wproxy.gmail.com with SMTP id i12so1240601wra
	for <freebsd-hackers@freebsd.org>; Sun, 05 Mar 2006 10:41:48 -0800 (PST)
DomainKey-Signature: a=rsa-sha1; q=dns; c=nofws; s=beta; d=gmail.com;
	h=received:message-id:date:from:to:subject:cc:mime-version:content-type;
	b=qp8SLMpv5ipYvgSaTilN8kCNjJ2V4eb0QpDHRpPfUKTBaBH7aR9ZZErhY4JejRGW1xgfMtA1NB2Nm4ZyY3K1GkJBYpb68/d/JRIBt1Ywfsd/bPbB3WvkYi6hJ8k/KxsDbY0R3Rmfx6Z9QIMBmLQ4J/GA1j9ch7+AnyuR42ztRds=
Received: by 10.54.62.3 with SMTP id k3mr4084352wra;
	Sun, 05 Mar 2006 10:41:48 -0800 (PST)
Received: by 10.54.119.2 with HTTP; Sun, 5 Mar 2006 10:41:47 -0800 (PST)
Message-ID: <5007e1a40603051041wc59ae7ar97d71ac3746f611f@mail.gmail.com>
Date: Mon, 6 Mar 2006 00:11:47 +0530
From: "Pranav Sawargaonkar" <pranav.sawargaonkar@gmail.com>
To: anupamdeshpande@gmail.com
MIME-Version: 1.0
Content-Type: text/plain; charset=ISO-8859-1
Content-Transfer-Encoding: quoted-printable
Content-Disposition: inline
X-Content-Filtered-By: Mailman/MimeDel 2.1.5
Cc: freebsd-hackers@freebsd.org
Subject: RE:Using open system call in KLD
X-BeenThere: freebsd-hackers@freebsd.org
X-Mailman-Version: 2.1.5
Precedence: list
List-Id: Technical Discussions relating to FreeBSD
	<freebsd-hackers.freebsd.org>
List-Unsubscribe: <http://lists.freebsd.org/mailman/listinfo/freebsd-hackers>, 
	<mailto:freebsd-hackers-request@freebsd.org?subject=unsubscribe>
List-Archive: <http://lists.freebsd.org/pipermail/freebsd-hackers>
List-Post: <mailto:freebsd-hackers@freebsd.org>
List-Help: <mailto:freebsd-hackers-request@freebsd.org?subject=help>
List-Subscribe: <http://lists.freebsd.org/mailman/listinfo/freebsd-hackers>,
	<mailto:freebsd-hackers-request@freebsd.org?subject=subscribe>
X-List-Received-Date: Sun, 05 Mar 2006 18:41:50 -0000

On 3/5/06, Anupam Deshpande <anupamdeshpande@gmail.com> wrote:
>
> >Hello,
>        >  I have used open system call in KLD to create >a file. But afte=
r
> >inserting the module the file is not created though >the file descriptor
> >returned is non zero. I also used close system call to >close the file,
> using
> >the descriptor returned by open system call.
>
>

Instead of
>int f_open(void)
>{
   >struct open_args o;
   >struct close_args c;
   >struct thread *td =3D curthread;
   >int fd;
   >o.path =3D "/home/file1.c";
   >o.flags =3D O_CREAT | O_RDWR | O_APPEND;
   >o.mode =3D 777;
   >fd =3D open(td,&a);
   >printf("\nFile descriptor  =3D %d",fd);
   >c.fd =3D fd;
   >close(td,&c);
>}

U need to change it to
int f_open(void)
{
   struct open_args o;
   struct close_args c;
   struct thread *td =3D curthread;
   int fd;
   o.path =3D "/home/file1.c";
   o.flags =3D O_CREAT | O_RDWR | O_APPEND;
   o.mode =3D 777;

 />>/fd =3D open(td,&a);

/*Beacuse open passes UIO_USERSPACE and you are   using open from KLD thus
you need to change it to UIO_SYSSPACE and also need to use  kern_open()
which is defined in #include <sys/syscallsubr.h>
as below*/

fd=3Dkern_open(td,o.path, UIO_SYSSPACE, o.flags,o.mode);


   printf("\nFile descriptor  =3D %d",fd);
   c.fd =3D fd;
   close(td,&c);
}
  -Pranav Sawargaonkar