RE: Unable to read/write in kernel module

Subject: RE: Unable to read/write in kernel module

From: "Junhan Zhang \(junhan\)" <junhan@xxxxxxxxx>

Date: Mon, 18 Dec 2006 10:21:01 -0800

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Thread-topic: Unable to read/write in kernel module

Title: Re: Unable to read/write in kernel module

I read the FAQ. Technically, it is right, but useless.8-( I have a kernel module to do the statistic for compactflash partition 1, and have to save to partition 2. I am using kernel 2.6.11 . Do you have any good idea to do it? Thanks.

From: Erik Mouw [mailto:mouw@xxxxxxxxxxxx]
Sent: Mon 12/18/2006 4:12 AM
To: Junhan Zhang (junhan)
Cc: kernelnewbies@xxxxxxxxxxxx
Subject: Re: Unable to read/write in kernel module

On Sun, Dec 17, 2006 at 06:59:37PM -0800, Junhan Zhang (junhan) wrote:
> I have a compact flash with 2 partitions /dev/hda1 and /dev/hda2.
> I tried to open("/dev/hda2", O_RDWR, 0644); which is from user space.
> It is fine to write/read. However, after I moved to kernel module, I
> always got return 0 for read/write. My source code is below. Could
> you help me figure out the problem? Thanks.

Please read the FAQ:

http://kernelnewbies.org/FAQ/WhyWritingFilesFromKernelIsBad

Erik

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