1 <refentry id="vidioc-enumaudio">
3 <refentrytitle>ioctl VIDIOC_ENUMAUDIO</refentrytitle>
8 <refname>VIDIOC_ENUMAUDIO</refname>
9 <refpurpose>Enumerate audio inputs</refpurpose>
15 <funcdef>int <function>ioctl</function></funcdef>
16 <paramdef>int <parameter>fd</parameter></paramdef>
17 <paramdef>int <parameter>request</parameter></paramdef>
18 <paramdef>struct v4l2_audio *<parameter>argp</parameter></paramdef>
24 <title>Arguments</title>
28 <term><parameter>fd</parameter></term>
34 <term><parameter>request</parameter></term>
36 <para>VIDIOC_ENUMAUDIO</para>
40 <term><parameter>argp</parameter></term>
49 <title>Description</title>
51 <para>To query the attributes of an audio input applications
52 initialize the <structfield>index</structfield> field and zero out the
53 <structfield>reserved</structfield> array of a &v4l2-audio;
54 and call the <constant>VIDIOC_ENUMAUDIO</constant> ioctl with a pointer
55 to this structure. Drivers fill the rest of the structure or return an
56 &EINVAL; when the index is out of bounds. To enumerate all audio
57 inputs applications shall begin at index zero, incrementing by one
58 until the driver returns <errorcode>EINVAL</errorcode>.</para>
60 <para>See <xref linkend="vidioc-g-audio" /> for a description of
69 <term><errorcode>EINVAL</errorcode></term>
71 <para>The number of the audio input is out of bounds.</para>