On Tue, 5 Aug 1997, Colin Wood wrote:

> > Also, there is a 'u' hierarchy which is dedicated to whatever the
> > driver wants to do.
> 
> Would you mind explaining just exactly what you mean by this last
> sentence?

I think he means that the rest of the kernel has explicitly avoided
creating ioctls that use the 'U' character as a begining identifier.
This leaves a clear path for drivers to use 'U' ioctls for their own
special purposes.

-J