> On Tue, 05.01.10 07:39, David Henningsson (launchpad.web at epost.diwic.se) > wrote: > >> Hi, >> >> I'm trying to get RtKit for my application up and running, and in the >> lack >> of an rtkit mailing list I'm using this one as the closest I could find >> :-) >> >> I'm using the reference implementation almost unmodified and end up with >> an "org.freedesktop.DBus.Error.AccessDenied" - "Operation not permitted" >> error. It's the dbus_connection_send_with_reply_and_block that fails and >> I'm not sure whether it is coming from rtkit or from D-Bus itself. If >> I've >> done something wrong with setrlimit or sched_reset_on_fork, is that the >> error to expect? >> >> I know from the PulseAudio verbose log that PulseAudio itself manages to >> use RealTimeKit, it's just my app that fails. > > Hmm, maybe its a PK policy issue? > > Have you checked syslog? afair dbus-daemon writes something to syslog > if it denies access. > > Does the example "rtkit-test" work? Thanks for the pointers, they were most helpful. First, RtKit version is 0.4-0ubuntu2, OS is Ubuntu 10.04 (the development version). If that matters. I had trouble getting rtkit-test succeeding at first, and a long story short, I was likely affected by this bug: http://www.spinics.net/lists/linux-fsdevel/msg28757.html ...so I had to try an bleeding edge kernel, in which rtkit-test works. After some additional debugging, I found that my original problem was that the rt-priority I requested was too high for rtkit to accept. So the permission problem comes from rtkit, the process_set_realtime() call returns -EPERM. So an additional question: would it be possible to either detect that highest value rtkit can deliver, or say "hey, I want x, but if you only can give me y, do that instead of failing"? In worst case, I could do a binary search, but I'm glad if that could be avoided :-) The same would be nice for the maximum value of RLIMIT_RTTIME. This is one of the things I love most about Linux/FOSS, the ability to debug wherever you want. I ended up inserting some debug prints in rtkit-daemon to nail the problem down - had rtkit been a Windows system service delivered by Microsoft, I'd probably still be stuck! // David
