RFD: Rework/extending functionality of mdev

[Laurent Bercot]

On 13/03/2015 21:32, Michael Conrad wrote:
> I stand corrected.  I thought there would be a partial write if the
> pipe was mostly full, but indeed, it blocks.

  Except you have to make the writes blocking, which severely limits
what the writers can do - no asynchronous event loop. For a simple
"cat"-equivalent between the netlink and a fifo, it's enough, but
it's about all it's good for. And such a "cat"-equivalent is still
useless.

  It's still a very bad idea to allow writes from different sources
into a single fifo when there's only one authoritative source of data,
in this case the netlink. If a process wants to read uevents from a
pipe, it can simply read from an anonymous pipe, being spawned by the
netlink listener. That's what my s6-uevent-listener and Natanael's
nldev do, and I agree with you: there's simply no need to introduce
fifos into the picture.

-- 
  Laurent