[alsa-devel] snd_ctl_elem_list

Newbie. Trying to discover information about the audio hardware. Specifically about a USB microphone ( Audio-Technia AT2020USB ) and whether it has a volume control. Writing in Ada just to be difficult. Not having any problems with that though.

After doing a malloc and a snd_ctl_elem_list I can use ctl_elem_list_count to get the number of elements. This number is non-zero ( 2 for the AT2020, 34 for the on-board Intel audio chip ).

Then I can use ctl_elem_to get the number of used. That number is zero and prevents me from trying to access the element list.

How can I find out information about the elements in the list? How do these elements become used? Is this even the correct path to try to discover the volume control?

Thanks,

Paul I