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Date: Fri, 17 Jun 2005 14:06:24 +0200
From: Hannes Mayer <debiandude@gmail.com>
To: freebsd-stable@freebsd.org
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Subject: Kernel module/IPC with userland: create and write to FIFO
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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.