From owner-freebsd-hackers Fri Jul 30 1:11:28 1999 Delivered-To: freebsd-hackers@freebsd.org Received: from dingo.cdrom.com (castles548.castles.com [208.214.165.112]) by hub.freebsd.org (Postfix) with ESMTP id A3A0415692 for ; Fri, 30 Jul 1999 01:11:24 -0700 (PDT) (envelope-from mike@dingo.cdrom.com) Received: from dingo.cdrom.com (localhost [127.0.0.1]) by dingo.cdrom.com (8.9.3/8.8.8) with ESMTP id BAA01302; Fri, 30 Jul 1999 01:05:52 -0700 (PDT) (envelope-from mike@dingo.cdrom.com) Message-Id: <199907300805.BAA01302@dingo.cdrom.com> X-Mailer: exmh version 2.0.2 2/24/98 To: Brian McGovern Cc: hackers@freebsd.org Subject: Re: reserved/local ioctl values? In-reply-to: Your message of "Tue, 27 Jul 1999 09:52:29 EDT." <199907271352.JAA09275@bmcgover-pc.cisco.com> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Date: Fri, 30 Jul 1999 01:05:52 -0700 From: Mike Smith Sender: owner-freebsd-hackers@FreeBSD.ORG Precedence: bulk X-Loop: FreeBSD.ORG > I'l looking at defining about a dozen ioctl calls for a local device driver. > When looking at the _IO, _IO, _IOW, _IOR, and _IOWR macros, I'm interested if > there are any "reserved" or "local" values for the first parameter? Not really, as such. > In short, I'd hate to use a seemly unused value, just to suddenly be in > conflict with a major set of ioctls (particularly terminal, as this is the > type of driver it will be). Also, would it be wise to reuse an existing value? If you want to add private ioctls to a given subsystem, either pick an arbitrarily high function number, or another letter that's not commonly associated with that subsystem. Eg. I would probably pick 'z' if I were going to add a local ioctl to the tty subsystem. -- \\ The mind's the standard \\ Mike Smith \\ of the man. \\ msmith@freebsd.org \\ -- Joseph Merrick \\ msmith@cdrom.com To Unsubscribe: send mail to majordomo@FreeBSD.org with "unsubscribe freebsd-hackers" in the body of the message