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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-std">
2	  <refmeta>
3	    <refentrytitle>ioctl VIDIOC_G_STD, VIDIOC_S_STD</refentrytitle>
4	    &manvol;
5	  </refmeta>
6	
7	  <refnamediv>
8	    <refname>VIDIOC_G_STD</refname>
9	    <refname>VIDIOC_S_STD</refname>
10	    <refpurpose>Query or select the video standard of the current 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>v4l2_std_id
20	*<parameter>argp</parameter></paramdef>
21	      </funcprototype>
22	    </funcsynopsis>
23	    <funcsynopsis>
24	      <funcprototype>
25		<funcdef>int <function>ioctl</function></funcdef>
26		<paramdef>int <parameter>fd</parameter></paramdef>
27		<paramdef>int <parameter>request</parameter></paramdef>
28		<paramdef>const v4l2_std_id
29	*<parameter>argp</parameter></paramdef>
30	      </funcprototype>
31	    </funcsynopsis>
32	  </refsynopsisdiv>
33	
34	  <refsect1>
35	    <title>Arguments</title>
36	
37	    <variablelist>
38	      <varlistentry>
39		<term><parameter>fd</parameter></term>
40		<listitem>
41		  <para>&fd;</para>
42		</listitem>
43	      </varlistentry>
44	      <varlistentry>
45		<term><parameter>request</parameter></term>
46		<listitem>
47		  <para>VIDIOC_G_STD, VIDIOC_S_STD</para>
48		</listitem>
49	      </varlistentry>
50	      <varlistentry>
51		<term><parameter>argp</parameter></term>
52		<listitem>
53		  <para></para>
54		</listitem>
55	      </varlistentry>
56	    </variablelist>
57	  </refsect1>
58	
59	  <refsect1>
60	    <title>Description</title>
61	
62	    <para>To query and select the current video standard applications
63	use the <constant>VIDIOC_G_STD</constant> and <constant>VIDIOC_S_STD</constant> ioctls which take a pointer to a
64	&v4l2-std-id; type as argument. <constant>VIDIOC_G_STD</constant> can
65	return a single flag or a set of flags as in &v4l2-standard; field
66	<structfield>id</structfield>. The flags must be unambiguous such
67	that they appear in only one enumerated <structname>v4l2_standard</structname> structure.</para>
68	
69	    <para><constant>VIDIOC_S_STD</constant> accepts one or more
70	flags, being a write-only ioctl it does not return the actual new standard as
71	<constant>VIDIOC_G_STD</constant> does. When no flags are given or
72	the current input does not support the requested standard the driver
73	returns an &EINVAL;. When the standard set is ambiguous drivers may
74	return <errorcode>EINVAL</errorcode> or choose any of the requested
75	standards. If the current input or output does not support standard video timings (e.g. if
76	&VIDIOC-ENUMINPUT; does not set the <constant>V4L2_IN_CAP_STD</constant> flag), then
77	&ENODATA; is returned.</para>
78	  </refsect1>
79	
80	  <refsect1>
81	    &return-value;
82	
83	    <variablelist>
84	      <varlistentry>
85		<term><errorcode>EINVAL</errorcode></term>
86		<listitem>
87		  <para>The <constant>VIDIOC_S_STD</constant> parameter was unsuitable.</para>
88		</listitem>
89	      </varlistentry>
90	      <varlistentry>
91		<term><errorcode>ENODATA</errorcode></term>
92		<listitem>
93		  <para>Standard video timings are not supported for this input or output.</para>
94		</listitem>
95	      </varlistentry>
96	    </variablelist>
97	  </refsect1>
98	</refentry>
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