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+<refentry id="vidioc-g-input">
+ <refmeta>
+ <refentrytitle>ioctl VIDIOC_G_INPUT, VIDIOC_S_INPUT</refentrytitle>
+ &manvol;
+ </refmeta>
+
+ <refnamediv>
+ <refname>VIDIOC_G_INPUT</refname>
+ <refname>VIDIOC_S_INPUT</refname>
+ <refpurpose>Query or select the current video input</refpurpose>
+ </refnamediv>
+
+ <refsynopsisdiv>
+ <funcsynopsis>
+ <funcprototype>
+ <funcdef>int <function>ioctl</function></funcdef>
+ <paramdef>int <parameter>fd</parameter></paramdef>
+ <paramdef>int <parameter>request</parameter></paramdef>
+ <paramdef>int *<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_G_INPUT, VIDIOC_S_INPUT</para>
+ </listitem>
+ </varlistentry>
+ <varlistentry>
+ <term><parameter>argp</parameter></term>
+ <listitem>
+ <para></para>
+ </listitem>
+ </varlistentry>
+ </variablelist>
+ </refsect1>
+
+ <refsect1>
+ <title>Description</title>
+
+ <para>To query the current video input applications call the
+<constant>VIDIOC_G_INPUT</constant> ioctl with a pointer to an integer
+where the driver stores the number of the input, as in the
+&v4l2-input; <structfield>index</structfield> field. This ioctl will
+fail only when there are no video inputs, returning
+<errorcode>EINVAL</errorcode>.</para>
+
+ <para>To select a video input applications store the number of the
+desired input in an integer and call the
+<constant>VIDIOC_S_INPUT</constant> ioctl with a pointer to this
+integer. Side effects are possible. For example inputs may support
+different video standards, so the driver may implicitly switch the
+current standard. Because of these possible side effects applications
+must select an input before querying or negotiating any other parameters.</para>
+
+ <para>Information about video inputs is available using the
+&VIDIOC-ENUMINPUT; ioctl.</para>
+ </refsect1>
+
+ <refsect1>
+ &return-value;
+
+ <variablelist>
+ <varlistentry>
+ <term><errorcode>EINVAL</errorcode></term>
+ <listitem>
+ <para>The number of the video input is out of bounds.</para>
+ </listitem>
+ </varlistentry>
+ </variablelist>
+ </refsect1>
+</refentry>