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author | Hans Verkuil <hverkuil@xs4all.nl> | 2009-01-18 13:00:12 +0100 |
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committer | Hans Verkuil <hverkuil@xs4all.nl> | 2009-01-18 13:00:12 +0100 |
commit | 8d4f9d241cdbd71a882a852c6e9285de279c0f87 (patch) | |
tree | 7f1fd2a5818e435c9dd920f60dc17244ef6e02e7 /v4l2-spec/vidioc-g-input.sgml | |
parent | b0fc8c78cb5fd9394d8d4ff3198bdc9390b96001 (diff) | |
download | mediapointer-dvb-s2-8d4f9d241cdbd71a882a852c6e9285de279c0f87.tar.gz mediapointer-dvb-s2-8d4f9d241cdbd71a882a852c6e9285de279c0f87.tar.bz2 |
v4l2spec: add version 0.24 of the spec
From: Hans Verkuil <hverkuil@xs4all.nl>
Priority: normal
Signed-off-by: Hans Verkuil <hverkuil@xs4all.nl>
Diffstat (limited to 'v4l2-spec/vidioc-g-input.sgml')
-rw-r--r-- | v4l2-spec/vidioc-g-input.sgml | 100 |
1 files changed, 100 insertions, 0 deletions
diff --git a/v4l2-spec/vidioc-g-input.sgml b/v4l2-spec/vidioc-g-input.sgml new file mode 100644 index 000000000..ed076e927 --- /dev/null +++ b/v4l2-spec/vidioc-g-input.sgml @@ -0,0 +1,100 @@ +<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. It is good practice to 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, or +there are no video inputs at all and this ioctl is not +supported.</para> + </listitem> + </varlistentry> + <varlistentry> + <term><errorcode>EBUSY</errorcode></term> + <listitem> + <para>I/O is in progress, the input cannot be +switched.</para> + </listitem> + </varlistentry> + </variablelist> + </refsect1> +</refentry> + +<!-- +Local Variables: +mode: sgml +sgml-parent-document: "v4l2.sgml" +indent-tabs-mode: nil +End: +--> |