freebsd stable - Jun 2005 - Kernel module/IPC with userland: create and write to FIFO

Hi all!

I've modified a standard driver and now I'd like to create a FIFO in
it to communicate / send data to a userland process.

Opening, reading and writing to a FIFO in userland is easy, but I have
no clue how to do this in kernel space. Googling and looking to the
kernel source didn't help.
The only thing I found is "kern_mkfifo" and int mkfifo(struct thread,
struct mkfifo_args);, but no example on how to use them (if that's the
right approach anyway).

To cut a long story short, how can I open a FIFO in kernel space and
write to it, so I can open and read from it in userspace ?

Thanks in advance for any hints!
Best regards,
Hannes.

On Fri, 17 Jun 2005 21:36, Hannes Mayer wrote:
> To cut a long story short, how can I open a FIFO in kernel space and
> write to it, so I can open and read from it in userspace ?
Why don't you create a device node?

If you read and write to it, it acts like a FIFO.

-- 
Daniel O'Connor software and network engineer
for Genesis Software - http://www.gsoft.com.au
"The nice thing about standards is that there
are so many of them to choose from."
  -- Andrew Tanenbaum
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Daniel, Alexander,

thanks a lot for your suggestions.
So far I've made good progress. For the time being I'll buffer in
kernel space - I'll look into the pipe stuff later. I just implemented
tsleep and wakeup for the read blocking. After major problems when
starting, this is going to be fun :-)

Thanks again,
Hannes.