interview question how does application connects to device

[Shaz]

On Tue, Jul 5, 2011 at 9:15 AM, Bond <jamesbond.2k.g at gmail.com> wrote:

> This is an interview question.
>
> I had written device driver for a char device so I know that code
> structure looks like this
>
> struct file_operations something {
>  .owner=my_device_open;
>  .read=my_device_read;
>  .close=my_device_close;
>  .write=my_device_write;
>
>  }
> When the device driver is active then in
>
> /dev/mydevice
> you can actually read and write into it. But what I was not clear is
> how an application will read or write to this device. I know insmod
> will insert the module to kernel,and register_chrdev(); will register
> the driver in kernel but how will application program communicate with
> this driver.
>
>
> My answer was
> In unix it simply opens the device node as a file and sends/receives
> data and commands from it.
>
> But he was expecting some thing more complex.
>
> _______________________________________________
> Kernelnewbies mailing list
> Kernelnewbies at kernelnewbies.org
> http://lists.kernelnewbies.org/mailman/listinfo/kernelnewbies
>

Hi,

Not in touch with low level stuff for some time but do check ioctl() and
sysfs on wikipedia or man pages.

Take care.

-- 
Shahbaz Khan
R&D Engineer,
Tactical Engineering and Consultancy.

http://shazkhan.wordpress.com/
http://pk.linkedin.com/pub/shahbaz-khan/20/116/b49
http://imsciences.edu.pk/serg/
http://csrdu.org/
+92-91-332-9915828
-------------- next part --------------
An HTML attachment was scrubbed...
URL: http://lists.kernelnewbies.org/pipermail/kernelnewbies/attachments/20110705/66a69140/attachment.html