Re: upcalls from kernel code to user space daemons

[Tim Hockin]

On Mon, Jun 14, 2004 at 06:22:48PM -0400, Chris Friesen wrote:
> > > Not quite.  The userspace is passing data down as well.  I don't know 
> >how you'd
> > > do that with read().
> >
> >For this you use write().

> Although I have to admit it's not pretty, and the performance improvements 
> may not be worth the obfuscation of the code.

You know, I've never understood why people hate ioctl.  Sometimes, it
really is what you want.  Why impose structured data onto a 2-way
unstructred system (read/write) when you have a structured system at hand
(ioctl).

I like ioctl() when it makes sense.  read() and write() are for data.
ioctl is for (tada!) control.
-
To unsubscribe from this list: send the line "unsubscribe linux-kernel" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at  http://vger.kernel.org/majordomo-info.html
Please read the FAQ at  http://www.tux.org/lkml/