On Mar 17, 2006, at 1:02 PM, Garrett D'Amore wrote:

> No.  Application starts thread, which issues ioctl that never returns.
> The ioctl code causes the thread to call tsleep when no data in the  
> queue.
>
> Then I can "kick" that thread after adding stuff to the queue by  
> calling
> _lwp_wakeup().

...which is still a full-expense system call.  I would like to have  
the details of this hidden in some userland API, too... in  
particular, I don't think the pthread -> LWP binding is generally  
public data.

-- thorpej