From nobody Sat Mar 16 15:45:04 2024 X-Original-To: freebsd-multimedia@mlmmj.nyi.freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2610:1c1:1:606c::19:1]) by mlmmj.nyi.freebsd.org (Postfix) with ESMTP id 4Txln133RJz5F3Wq for ; Sat, 16 Mar 2024 15:45:09 +0000 (UTC) (envelope-from dev@submerge.ch) Received: from gozo.iway.ch (gozo.iway.ch [212.25.24.36]) (using TLSv1.2 with cipher ECDHE-RSA-AES256-GCM-SHA384 (256/256 bits)) (Client did not present a certificate) by mx1.freebsd.org (Postfix) with ESMTPS id 4Txln10tqPz4LCP; Sat, 16 Mar 2024 15:45:09 +0000 (UTC) (envelope-from dev@submerge.ch) Authentication-Results: mx1.freebsd.org; none Received: from gozo.iway.ch (localhost [127.0.0.1]) by localhost (Postfix) with ESMTP id 8F16334050F; Sat, 16 Mar 2024 16:45:05 +0100 (CET) X-Iway-Path: 0 Received: from localhost (localhost [127.0.0.1]) by localhost (ACF/28147.26046); Sat, 16 Mar 2024 16:45:05 +0100 (CET) Received: from interway.li (sendai-nord.iway.ch [212.25.24.38]) by gozo.iway.ch (Postfix) with ESMTP; Sat, 16 Mar 2024 16:45:05 +0100 (CET) Received: from [145.40.196.39] (account fw@submerge.ch HELO x230.localnet) by sendai-nord.interway.li (CommuniGate Pro SMTP 7.1.0) with ESMTPSA id 259493139; Sat, 16 Mar 2024 16:45:05 +0100 From: Florian Walpen To: Christos Margiolis , freebsd-multimedia@freebsd.org Cc: status-updates@freebsdfoundation.org, freebsd-multimedia@freebsd.org, jrm@freebsd.org, Mark Johnston Subject: Re: [Development report #7] Audio Stack Improvements Date: Sat, 16 Mar 2024 16:45:04 +0100 Message-ID: <1895870.vslOlgHxSZ@x230> In-Reply-To: References: List-Id: Multimedia discussions List-Archive: https://lists.freebsd.org/archives/freebsd-multimedia List-Help: List-Post: List-Subscribe: List-Unsubscribe: Sender: owner-freebsd-multimedia@freebsd.org MIME-Version: 1.0 Content-Transfer-Encoding: 7Bit Content-Type: text/plain; charset="us-ascii" X-Spamd-Bar: ---- X-Rspamd-Pre-Result: action=no action; module=replies; Message is reply to one we originated X-Spamd-Result: default: False [-4.00 / 15.00]; REPLY(-4.00)[]; ASN(0.00)[asn:8758, ipnet:212.25.0.0/19, country:CH] X-Rspamd-Queue-Id: 4Txln10tqPz4LCP On Saturday, March 16, 2024 3:38:01 AM CET Mark Johnston wrote: > On Fri, Mar 15, 2024 at 06:00:16PM +0100, Christos Margiolis wrote: > > Hello Mark, > > > > Mark Johnston wrote: > > > > Behavior changes: > > > > - Only one /dev/dspX device is exposed, as opposed to the current > > > > > > > > /dev/dspX.[X]X devices created by the snd_clone mechanism. The > > > > user/application now only needs to access the device through > > > > /dev/dspX > > > > or /dev/dsp and sound(4) will take care of all necessary audio > > > > routing. > > > > > > Does this represent a backward compatibility break? That is, will > > > applications need any modification when running on a patched kernel? > > > > Applications are meant to open an audio device through /dev/dsp (if > > hw.snd.basename_clone is enabled), or through /dev/dspX, so the vast > > majority of applications should work with no problems. > > > > Applications that open a device through /dev/dspX.[X]X will break with > > this patch. However, opening a device like this is discouraged anyway, > > > according to the sound(4) man page (see FILES section): > To your knowledge, do any popular applications actually do this? A > comment in the man page isn't very important if applications end up > ignoring it. :) Is it even possible to open pcm devices through /dev/dspX.Y currently? I remember that I stumbled upon this when I developed the Jack backend and it wasn't possible to open /dev/dspX.Y, I had to use /dev/dspX. Just checked and that still seems to be the case on 14.0-RELEASE. Unless I missed something, I'd conclude that it's not used in ports :-) Non-clone aliases like /dev/dsp_mmap seem to work though, never actually seen them in use but I think we should preserve them as part of OSSv4 compatibility. Florian