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Date: Tue, 8 Dec 2015 00:04:26 +1100 (EST)
From: Ian Smith <smithi@nimnet.asn.au>
To: Lu?s Fernando Schultz Xavier da Silveira <schultz@ime.usp.br>
cc: freebsd-questions@freebsd.org
Subject: Re: OSS in jail
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In freebsd-questions Digest, Vol 601, Issue 1, Message: 4
On Sun, 6 Dec 2015 17:44:01 -0200
Lu?s Fernando Schultz Xavier da Silveira <schultz@ime.usp.br> wrote:

 > I would like one of my jails to have the ability to play back sound,
 > but not to record it. As I understand, sound is played back by writing
 > to /dev/dsp and recorded by reading from it. Hence, placing the /dev/dsp
 > device (and /dev/dsp[0-9]* devices) in the jail via devfs.rules is not
 > a solution since the jail superuser can override permissions on these
 > devices and even read from them when they lack read permission.
 > 
 > Is there a way to give a device to a jail in read-only mode?
 > If not, is it possible to create a virtual OSS stack and give that to
 > the jail?
 > How would you solve this problem?
 > 
 > Also, is it possible to give the jail a mixer device that can only read
 > mixer settings but not alter them?
 > 
 > Thanks,
 > Lu?s

Sorry about charset mapping ..

I suggest asking this (interesting) question in either or both of
freebsd-jail@freebsd.org and freebsd-multimedia@freebsd.org .

I'm vaguely wondering if you could use port audio/jack for this, but 
I've only used that on Linux, and that with ALSA .. but I expect you 
should find some help from the habitual denizens of those lists.

cheers, Ian