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Diffstat (limited to 'Documentation/DocBook/media/v4l/vidioc-enumaudioout.xml')
-rw-r--r-- | Documentation/DocBook/media/v4l/vidioc-enumaudioout.xml | 79 |
1 files changed, 79 insertions, 0 deletions
diff --git a/Documentation/DocBook/media/v4l/vidioc-enumaudioout.xml b/Documentation/DocBook/media/v4l/vidioc-enumaudioout.xml new file mode 100644 index 000000000..2e87cedb0 --- /dev/null +++ b/Documentation/DocBook/media/v4l/vidioc-enumaudioout.xml @@ -0,0 +1,79 @@ +<refentry id="vidioc-enumaudioout"> + <refmeta> + <refentrytitle>ioctl VIDIOC_ENUMAUDOUT</refentrytitle> + &manvol; + </refmeta> + + <refnamediv> + <refname>VIDIOC_ENUMAUDOUT</refname> + <refpurpose>Enumerate audio outputs</refpurpose> + </refnamediv> + + <refsynopsisdiv> + <funcsynopsis> + <funcprototype> + <funcdef>int <function>ioctl</function></funcdef> + <paramdef>int <parameter>fd</parameter></paramdef> + <paramdef>int <parameter>request</parameter></paramdef> + <paramdef>struct v4l2_audioout *<parameter>argp</parameter></paramdef> + </funcprototype> + </funcsynopsis> + </refsynopsisdiv> + + <refsect1> + <title>Arguments</title> + + <variablelist> + <varlistentry> + <term><parameter>fd</parameter></term> + <listitem> + <para>&fd;</para> + </listitem> + </varlistentry> + <varlistentry> + <term><parameter>request</parameter></term> + <listitem> + <para>VIDIOC_ENUMAUDOUT</para> + </listitem> + </varlistentry> + <varlistentry> + <term><parameter>argp</parameter></term> + <listitem> + <para></para> + </listitem> + </varlistentry> + </variablelist> + </refsect1> + + <refsect1> + <title>Description</title> + + <para>To query the attributes of an audio output applications +initialize the <structfield>index</structfield> field and zero out the +<structfield>reserved</structfield> array of a &v4l2-audioout; and +call the <constant>VIDIOC_G_AUDOUT</constant> 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 <errorcode>EINVAL</errorcode>.</para> + + <para>Note connectors on a TV card to loop back the received audio +signal to a sound card are not audio outputs in this sense.</para> + + <para>See <xref linkend="vidioc-g-audioout" /> for a description of +&v4l2-audioout;.</para> + </refsect1> + + <refsect1> + &return-value; + + <variablelist> + <varlistentry> + <term><errorcode>EINVAL</errorcode></term> + <listitem> + <para>The number of the audio output is out of bounds.</para> + </listitem> + </varlistentry> + </variablelist> + </refsect1> +</refentry> |