7.11. ioctl VIDIOC_ENUMAUDIO¶
7.11.1. Name¶
VIDIOC_ENUMAUDIO - Enumerate audio inputs
7.11.3. Arguments¶
fd- File descriptor returned by
open(). argp- Pointer to struct
v4l2_audio.
7.11.4. Description¶
To query the attributes of an audio input applications initialize the
index field and zero out the reserved array of a struct
v4l2_audio and call the ioctl VIDIOC_ENUMAUDIO
ioctl with a pointer to this structure. Drivers fill the rest of the
structure or return an EINVAL error code when the index is out of
bounds. To enumerate all audio inputs applications shall begin at index
zero, incrementing by one until the driver returns EINVAL.
See VIDIOC_G_AUDIO for a description of struct
v4l2_audio.
7.11.5. Return Value¶
On success 0 is returned, on error -1 and the errno variable is set
appropriately. The generic error codes are described at the
Generic Error Codes chapter.
- EINVAL
- The number of the audio input is out of bounds.