The virtual audio utility enables developers to interactively configure/control virtual audio devices, through the virtual_audio driver.
To add an input and an output device with default configurations in one call to virtual_audio:
$ virtual_audio --add --in --add --wait Executing `--add' command... Executing `--in' command... Executing `--add' command... Executing `--wait' command... Press Q to cancel, or any other key to continue...
The first --add adds an output device, then --in shifts to reference the configuration of an input device, then the second --add adds an input device.
Note: without --wait the utility exits upon completion, which drops all FIDL connections (thus closing all devices).
The --wait option can be used to execute commands one at a time, waiting for a key press before proceeding. This is useful for observing changes like plug/unplug, or clock rate changes, such as:
$ virtual_audio --domain=1 --add --wait --rate=1000 --wait Executing `--domain' command... Executing `--add' command... Executing `--wait' command... Press Q to cancel, or any other key to continue... Executing `--rate' command... Executing `--wait' command... Press Q to cancel, or any other key to continue... $ virtual_audio --domain=1 --add --wait --rate=1000 --wait --unplug --wait Executing `--domain' command... Executing `--add' command... Executing `--wait' command... Press Q to cancel, or any other key to continue... Executing `--rate' command... Executing `--wait' command... Press Q to cancel, or any other key to continue... Executing `--unplug' command... Executing `--wait' command... Press Q to cancel, or any other key to continue...