Re: LANANA: To Pending Device Number Registrants

H. Peter Anvin
2001-05-15T20:31:18Z

Alexander Viro wrote:
>
> On Tue, 15 May 2001, James Simmons wrote:
>
> > > only one _device_node_, you can have multiple fd's. In fact, you can, with
> > > the Linux VFS layer, fairly easily do things like
> > >
> > > mknod /dev/fd0 c X Y
> > >
> > > and then use
> > >
> > > fd = open("/dev/fd0/colourspace", O_RDWR);
> >
> > Yipes!! I have to say UNIX has a tendency to teach you ioctl is the only
> > way. I have never thought outside of the box nor see anyone else in this
> > manner. This is absolutely brillant!!! I can see alot of possibilties with
> > this.
>
> The thing being, why thet hell create these device/directory hybrids?
>

Permission management. The permissions on the subnodes are inherited
from the main node, which is stored on a persistent medium.

-hpa

--
<hpa@transmeta.com> at work, <hpa@zytor.com> in private!
"Unix gives you enough rope to shoot yourself in the foot."