Re: audio sink RuntimeError: audio_oss_sink

Wow. I didn't expect such a quick response; thank you all.  I noticed an option in the /etc/sysconfig/sound file:  # Load OSS-emulation modules at boot-up? (yes/no)  # OSS-emulation modules are needed if you use OSS applications  # with ALSA drivers.  This option specifies whether these modules are  # loaded at boot-time.  #  LOAD_OSS_EMUL_MODULES="yes"    For shits and giggles, I enabled it and found /dsp and /audio directories appeared after I next restarted the system.  After this, /dsp, /audio and blank work in the device field of the audio sink. The audio sink now works as well as  pulse audio (so system not broken for general use). The KDE pulse audio controls work with the audio sink although  pavucontrol& does not (audio sink reports  error: "audio_oss_sink: /dev/audio: Device or resource busy"). I don't  require pavucontrol so long as the KDE audio controls work.  Running aplay -L shows no change from before.   So I am happy to consider this resolved and no long a diversion from other aspects of gnuradio.  Perhaps in a couple of months I will be able to contribute something useful to the project.    cheers,  Rick  

Date: Fri, 14 Aug 2020 13:50:51 +0200  From: Marcus Müller <mueller@kit.edu>  To: <discuss-gnuradio@gnu.org>  Subject: Re: audio sink RuntimeError: audio_oss_sink  Message-ID: <c1e99e0b-0146-a0b9-520f-243c9d8b2b3a@kit.edu>  Content-Type: text/plain; charset="utf-8"    Hi Rick,    does it work when you put nothing in the device field? (because that  should select the default audio architecture, ALSA in your case, and use  the default device, which would be Pulse Audio sitting behind "default".)  Using "sysdefault" can normally fail, since that might not be a  shareable device. "default" is really what you'd normally be going for.  A program I like to use to see which programs use Pulseaudio, natively  or through the "default" ALSA device, by the way, is `pavucontrol`.    Best regards,  Marcus    On 14.08.20 00:27, aardric wrote:  

Hail,        I am introducing myself to SDR technology and gnuradio through  whatever project documentation I find, dissecting the code and executing  simple experimental flow graphs to test understanding of concepts,  hoping to avoid forum queries (this is my first). Although the audio  sink is not critical to my ultimate use of gnuradio and a bit of a  diversion I will eventually start digging into it. However, I thought to  submit a query on whether there is something obvious I should try in  order to get it working. I am using gnu radio companion 3.8.1.0 (Python  3.6.10) and feeding the audio sink with a 1 kHz tone from the signal  source block.    (1) staring with:  :~> aplay -L  null       Discard all samples (playback) or generate zero samples (capture)  default       Default ALSA Output (currently PulseAudio Sound Server)  sysdefault:CARD=PCH       HDA Intel PCH, ALC892 Analog       Default Audio Device  front:CARD=PCH,DEV=0       HDA Intel PCH, ALC892 Analog       Front speakers  surround21:CARD=PCH,DEV=0       HDA Intel PCH, ALC892 Analog       2.1 Surround output to Front and Subwoofer speakers  (...)  hdmi:CARD=PCH,DEV=0       HDA Intel PCH, HDMI 0       HDMI Audio Output  hdmi:CARD=PCH,DEV=1       HDA Intel PCH, HDMI 1       HDMI Audio Output  hdmi:CARD=PCH,DEV=2       HDA Intel PCH, HDMI 2       HDMI Audio Output  hdmi:CARD=PCH,DEV=3       HDA Intel PCH, HDMI 3       HDMI Audio Output  hdmi:CARD=PCH,DEV=4       HDA Intel PCH, HDMI 4       HDMI Audio Output    (2) using sysdefault:CARD=PCH for the audio sink device name,  both 44.1 kS/s and 48 kS/s the following runtime error results:    (3)  gr::log :INFO: audio source - Audio sink arch: oss  audio_oss_sink: sysdefault:CARD=PCH: No such file or directory  Traceback (most recent call last):     File "/gnuradio/examples/audiotest.py", line 136, in <module>       main()     File "/gnuradio/examples/audiotest.py", line 112, in main       tb = top_block_cls()     File "/gnuradio/examples/audiotest.py", line 78, in __init__       self.audio_sink_0 = audio.sink(samp_rate, 'sysdefault:CARD=PCH', True)     File  "/usr/local/lib64/python3.6/site-packages/gnuradio/audio/audio_swig.py",  line 220, in make       return _audio_swig.sink_make(*args, **kwargs)  RuntimeError: audio_oss_sink     >>> Done (return code 1)    (4) Fixing this isn't critical and in time I will get to the bottom of  it; the forum query just removes the possibility of an obvious answer  that most everyone else knows about. My guess is that I have to disable  the Pulse audio server.      Rick