[Python-Dev] linuxaudiodev test does nothing

[Charles G Waldman]

Jeremy Hylton writes:
 >   >> I can play the .au file and I use a variety of other audio tools
 >   >> regularly.  Is Peter still maintaining it or can someone else
 >   >> offer some assistance?

The Linux audio programming docs do clearly state:

>    There are three parameters which affect quality (and memory/bandwidth requirements) of sampled audio
>    data. These parameters are the following:		    
>
>           Sample format (sometimes called as number of bits) 
>           Number of channels (mono/stereo) 
>           Sampling rate (speed) 
>
>           NOTE!  
>              It is important to set these parameters always in the above order. Setting speed before
>              number of channels doesn't work with all devices.  

linuxaudiodev.c does this:
    ioctl(self->x_fd, SOUND_PCM_WRITE_RATE, &rate)
    ioctl(self->x_fd, SNDCTL_DSP_SAMPLESIZE, &ssize)
    ioctl(self->x_fd, SNDCTL_DSP_STEREO, &stereo)
    ioctl(self->x_fd, SNDCTL_DSP_SETFMT, &audio_types[n].a_fmt)

which is exactly the reverse order of what is recommended!

Alas, even after fixing this, I *still* can't get linuxaudiodev to
play the damned .au file.  It works fine for the .wav formats.

I'll continue hacking on this as time permits.