From owner-freebsd-hackers  Sun Jan 12 11:20:03 1997
Return-Path: <owner-hackers>
Received: (from root@localhost)
          by freefall.freebsd.org (8.8.4/8.8.4) id LAA12034
          for hackers-outgoing; Sun, 12 Jan 1997 11:20:03 -0800 (PST)
Received: from phaeton.artisoft.com (phaeton.Artisoft.COM [198.17.250.211])
          by freefall.freebsd.org (8.8.4/8.8.4) with SMTP id LAA11992
          for <hackers@FreeBSD.org>; Sun, 12 Jan 1997 11:20:00 -0800 (PST)
Received: (from terry@localhost) by phaeton.artisoft.com (8.6.11/8.6.9) id MAA25927; Sun, 12 Jan 1997 12:06:32 -0700
From: Terry Lambert <terry@lambert.org>
Message-Id: <199701121906.MAA25927@phaeton.artisoft.com>
Subject: Re: DEVFS permissions &c.
To: davidn@unique.usn.blaze.net.au (David Nugent)
Date: Sun, 12 Jan 1997 12:06:32 -0700 (MST)
Cc: bde@zeta.org.au, joerg_wunsch@uriah.heep.sax.de, hackers@FreeBSD.org
In-Reply-To: <Mutt.19970112022600.davidn@labs.blaze.net.au> from "David Nugent" at Jan 12, 97 02:26:00 am
X-Mailer: ELM [version 2.4 PL24]
MIME-Version: 1.0
Content-Type: text/plain; charset=US-ASCII
Content-Transfer-Encoding: 7bit
Sender: owner-hackers@FreeBSD.org
X-Loop: FreeBSD.org
Precedence: bulk

> Bruce Evans writes:
> > >> I've exchanged a couple of thoughts with Bruce about it.  Maybe we
> > >> could teach mtree(8) to help in this step.
> > >
> > >Yes, that would certainly be the way to do it.
> > 
> > Not really.  Things it doesn't do right include:
> > - wildcards.  The equivalent of `chmod 666 /dev/tty[pqrs][PQRS]*' is a
> >   huge list.
> 
> This could be resolved. It will involve expanding mtree's syntax a
> little (about which I admit to knowing next to nothing :-)), 
> but I believe the basic functionality should be part of mtree, or
> if not mtree, then something along the same lines.

Isn't this a non-starter?

I mean, shouldn't pty's be handled by:

	int	clonefd;
	int	slavefd, masterfd;
	char	ptypath[ MAXNAMLEN];

	/*
	 * Open clone device
	 */
	clonefd = open( "/dev/pty", O_RD);

	/*
	 * Reserve cloned master/slave pair path
	 */
	ioctl( clonefd, PTYIOCALLOC, &ptypath);

	/*
	 * Open reserved FS object (always 'master').  This will
	 * hold the reference
	 */
	masterfd = open( ptypath, O_RDWR);

	/*
	 * Now that rreference is held, clone device is not necessary
	 */
	close( clonefd);

	/*
	 * Given an fd for the master, return an open fd on the slave;
	 * it is not necessary for the slave to have an FS namespace
	 * assignment (though it could, if it were needed for some
	 * program for compatability.
	 */
	ioctl( masterfd, PTYIOCSLAVE, &slavefd);

	...


With 'ptypath' ending up containing something like "/dev/pty/000"...
after all, there is no reason a "dir" can't be a device as well,
since you can use VOP_READDIR() to iterate subdevices and VOP_READ()
to operate on the device itself.


					Regards,
					Terry Lambert
					terry@lambert.org
---
Any opinions in this posting are my own and not those of my present
or previous employers.