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Based on kernel version 3.0.4. Page generated on 2011-10-03 22:07 EST.

1	<refentry id="vidioc-querystd">
2	  <refmeta>
3	    <refentrytitle>ioctl VIDIOC_QUERYSTD</refentrytitle>
4	    &manvol;
5	  </refmeta>
6	
7	  <refnamediv>
8	    <refname>VIDIOC_QUERYSTD</refname>
9	    <refpurpose>Sense the video standard received by the current
10	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 *<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_QUERYSTD</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>The hardware may be able to detect the current video
53	standard automatically. To do so, applications call <constant>
54	VIDIOC_QUERYSTD</constant> with a pointer to a &v4l2-std-id; type. The
55	driver stores here a set of candidates, this can be a single flag or a
56	set of supported standards if for example the hardware can only
57	distinguish between 50 and 60 Hz systems. When detection is not
58	possible or fails, the set must contain all standards supported by the
59	current video input or output.</para>
60	
61	  </refsect1>
62	
63	  <refsect1>
64	    &return-value;
65	
66	    <variablelist>
67	      <varlistentry>
68		<term><errorcode>EINVAL</errorcode></term>
69		<listitem>
70		  <para>This ioctl is not supported.</para>
71		</listitem>
72	      </varlistentry>
73	      <varlistentry>
74		<term><errorcode>EBUSY</errorcode></term>
75		<listitem>
76		  <para>The device is busy and therefore can not detect the standard</para>
77		</listitem>
78	      </varlistentry>
79	    </variablelist>
80	  </refsect1>
81	</refentry>
82	
83	<!--
84	Local Variables:
85	mode: sgml
86	sgml-parent-document: "v4l2.sgml"
87	indent-tabs-mode: nil
88	End:
89	-->
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