From owner-freebsd-current Sun Feb 2 12:27:31 1997 Return-Path: Received: (from root@localhost) by freefall.freebsd.org (8.8.5/8.8.5) id MAA09950 for current-outgoing; Sun, 2 Feb 1997 12:27:31 -0800 (PST) Received: from phaeton.artisoft.com (phaeton.Artisoft.COM [198.17.250.211]) by freefall.freebsd.org (8.8.5/8.8.5) with SMTP id MAA09941; Sun, 2 Feb 1997 12:27:28 -0800 (PST) Received: (from terry@localhost) by phaeton.artisoft.com (8.6.11/8.6.9) id NAA08478; Sun, 2 Feb 1997 13:25:21 -0700 From: Terry Lambert Message-Id: <199702022025.NAA08478@phaeton.artisoft.com> Subject: Re: device driver open semantics... To: bakul@torrentnet.com (Bakul Shah) Date: Sun, 2 Feb 1997 13:25:21 -0700 (MST) Cc: phk@freebsd.org, current@freebsd.org In-Reply-To: <199702021635.LAA21764@chai.plexuscom.com> from "Bakul Shah" at Feb 2, 97 11:35:43 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-current@freebsd.org X-Loop: FreeBSD.org Precedence: bulk > Most device drivers depend on a close() being the final close. Any > change in this semantics must provide a *significant* benefit to all > -- not just fix a few esoteric bugs. Adding more entry points would > also further complicate the interface. > > Perhaps the bugs Bruce mentioned (+ things that make you > dissatisfied with the way things work now) can be handled by passing > some more state between the two layers? May be a callback function? > > In any case, cases where the present *observed* behavior does > not cause faulty, unintended or inconsistent operation should remain > _invariant_ under any changes. IMHO, of course! I disagree. The driver should not depend on the system doing reference counting for it. Mark me down as being "for" calling the close once per close. Reference counting is a very simple modification to make, and there are great benefits to things like CDROM writers that can also function as readers, non-bidirectional sound cards, etc., etc.. Regards, Terry Lambert terry@lambert.org --- Any opinions in this posting are my own and not those of my present or previous employers.