ioctl VIDIOC_ENUMAUDOUT
&manvol;

# VIDIOC_ENUMAUDOUT

Enumerate audio outputs

    	int ioctl
    	int fd
    	int request
    	struct v4l2_audioout *argp

## Arguments

`fd`

  &fd;

`request`

  VIDIOC_ENUMAUDOUT

`argp`

## Description

To query the attributes of an audio output applications initialize the index field and zero out the reserved array of a &v4l2-audioout; and call the `VIDIOC_G_AUDOUT` ioctl with a pointer to this structure. Drivers fill the rest of the structure or return an &EINVAL; when the index is out of bounds. To enumerate all audio outputs applications shall begin at index zero, incrementing by one until the driver returns EINVAL.

Note connectors on a TV card to loop back the received audio signal to a sound card are not audio outputs in this sense.

See for a description of &v4l2-audioout;.

&return-value;

EINVAL

  The number of the audio output is out of bounds, or there are no audio outputs at all and this ioctl is not supported.