Re: How to avoid data copies in a driver ?

Francis Moreau
2008-05-15T07:41:49Z

Hello,

On Wed, May 14, 2008 at 11:23 PM, linux-os (Dick Johnson)
<linux-os@analogic.com> wrote:
> You memory-map the data. Impliment mmap() in your driver.
> You can also impliment poll() { select() } so your
> application knows when new data are available.
>
> You cannot use a user-mode file-descriptor in the kernel.
>

Why not ?

I'm suprised because what I need doens't seem so uncommon, usually
devices send or
receive data to/from files. So a helper (system call ?) to achieve
that other than the basic
read/write seems needed, no ?

--
Francis