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Based on kernel version 3.15.4. Page generated on 2014-07-07 09:02 EST.

1	<refentry id="vidioc-g-input">
2	  <refmeta>
3	    <refentrytitle>ioctl VIDIOC_G_INPUT, VIDIOC_S_INPUT</refentrytitle>
4	    &manvol;
5	  </refmeta>
6	
7	  <refnamediv>
8	    <refname>VIDIOC_G_INPUT</refname>
9	    <refname>VIDIOC_S_INPUT</refname>
10	    <refpurpose>Query or select the current video input</refpurpose>
11	  </refnamediv>
12	
13	  <refsynopsisdiv>
14	    <funcsynopsis>
15	      <funcprototype>
16		<funcdef>int <function>ioctl</function></funcdef>
17		<paramdef>int <parameter>fd</parameter></paramdef>
18		<paramdef>int <parameter>request</parameter></paramdef>
19		<paramdef>int *<parameter>argp</parameter></paramdef>
20	      </funcprototype>
21	    </funcsynopsis>
22	  </refsynopsisdiv>
23	
24	  <refsect1>
25	    <title>Arguments</title>
26	
27	    <variablelist>
28	      <varlistentry>
29		<term><parameter>fd</parameter></term>
30		<listitem>
31		  <para>&fd;</para>
32		</listitem>
33	      </varlistentry>
34	      <varlistentry>
35		<term><parameter>request</parameter></term>
36		<listitem>
37		  <para>VIDIOC_G_INPUT, VIDIOC_S_INPUT</para>
38		</listitem>
39	      </varlistentry>
40	      <varlistentry>
41		<term><parameter>argp</parameter></term>
42		<listitem>
43		  <para></para>
44		</listitem>
45	      </varlistentry>
46	    </variablelist>
47	  </refsect1>
48	
49	  <refsect1>
50	    <title>Description</title>
51	
52	    <para>To query the current video input applications call the
53	<constant>VIDIOC_G_INPUT</constant> ioctl with a pointer to an integer
54	where the driver stores the number of the input, as in the
55	&v4l2-input; <structfield>index</structfield> field. This ioctl will
56	fail only when there are no video inputs, returning
57	<errorcode>EINVAL</errorcode>.</para>
58	
59	    <para>To select a video input applications store the number of the
60	desired input in an integer and call the
61	<constant>VIDIOC_S_INPUT</constant> ioctl with a pointer to this
62	integer. Side effects are possible. For example inputs may support
63	different video standards, so the driver may implicitly switch the
64	current standard. Because of these possible side effects applications
65	must select an input before querying or negotiating any other parameters.</para>
66	
67	    <para>Information about video inputs is available using the
68	&VIDIOC-ENUMINPUT; ioctl.</para>
69	  </refsect1>
70	
71	  <refsect1>
72	    &return-value;
73	
74	    <variablelist>
75	      <varlistentry>
76		<term><errorcode>EINVAL</errorcode></term>
77		<listitem>
78		  <para>The number of the video input is out of bounds.</para>
79		</listitem>
80	      </varlistentry>
81	    </variablelist>
82	  </refsect1>
83	</refentry>
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