"Jack O'Quin":
I've been thinking about ways to use this feature to improve and
simplify the current security situation for Linux audio. No
conclusions, but here are some thoughts for discussion:
(1) There should a simple way for the sysadmin to reliably disallow
realtime privileges. One way to allow (or prevent) access to
realtime privileges for any program is via a sysctl global variable.
Of course, loading the kernel extension is a privileged operation,
anyway. But, I prefer some positive means of blocking it.
(2) Using sysctl, set a group id (like `audio') for which realtime
privileges are automatically granted. Then, we could just install
realtime apps with `setgid audio'. This seems much better than
opening things up to *any* application. And, audio applications
would not need root privileges any more. This would be a rather big
improvement over the current jackstart/jackd situation.
(3) We could also define a default realtime group (gid 0 maybe),
since `audio' probably does not exist on many distributions. IIUC,
this is originally a Debian idea. I don't know how widely it has
been adopted. I like it and think it should become a universal
Linux convention, allowing access to the sound card as well as
realtime privileges.
What about this one:
(4) Let the user that is currently physical logged in to the machine
get realtime privileges.
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