132 строки
3.4 KiB
XML
132 строки
3.4 KiB
XML
<refentry id="vidioc-dqevent">
|
|
<refmeta>
|
|
<refentrytitle>ioctl VIDIOC_DQEVENT</refentrytitle>
|
|
&manvol;
|
|
</refmeta>
|
|
|
|
<refnamediv>
|
|
<refname>VIDIOC_DQEVENT</refname>
|
|
<refpurpose>Dequeue event</refpurpose>
|
|
</refnamediv>
|
|
|
|
<refsynopsisdiv>
|
|
<funcsynopsis>
|
|
<funcprototype>
|
|
<funcdef>int <function>ioctl</function></funcdef>
|
|
<paramdef>int <parameter>fd</parameter></paramdef>
|
|
<paramdef>int <parameter>request</parameter></paramdef>
|
|
<paramdef>struct v4l2_event
|
|
*<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_DQEVENT</para>
|
|
</listitem>
|
|
</varlistentry>
|
|
<varlistentry>
|
|
<term><parameter>argp</parameter></term>
|
|
<listitem>
|
|
<para></para>
|
|
</listitem>
|
|
</varlistentry>
|
|
</variablelist>
|
|
</refsect1>
|
|
|
|
<refsect1>
|
|
<title>Description</title>
|
|
|
|
<para>Dequeue an event from a video device. No input is required
|
|
for this ioctl. All the fields of the &v4l2-event; structure are
|
|
filled by the driver. The file handle will also receive exceptions
|
|
which the application may get by e.g. using the select system
|
|
call.</para>
|
|
|
|
<table frame="none" pgwide="1" id="v4l2-event">
|
|
<title>struct <structname>v4l2_event</structname></title>
|
|
<tgroup cols="4">
|
|
&cs-str;
|
|
<tbody valign="top">
|
|
<row>
|
|
<entry>__u32</entry>
|
|
<entry><structfield>type</structfield></entry>
|
|
<entry></entry>
|
|
<entry>Type of the event.</entry>
|
|
</row>
|
|
<row>
|
|
<entry>union</entry>
|
|
<entry><structfield>u</structfield></entry>
|
|
<entry></entry>
|
|
<entry></entry>
|
|
</row>
|
|
<row>
|
|
<entry></entry>
|
|
<entry>&v4l2-event-vsync;</entry>
|
|
<entry><structfield>vsync</structfield></entry>
|
|
<entry>Event data for event V4L2_EVENT_VSYNC.
|
|
</entry>
|
|
</row>
|
|
<row>
|
|
<entry></entry>
|
|
<entry>__u8</entry>
|
|
<entry><structfield>data</structfield>[64]</entry>
|
|
<entry>Event data. Defined by the event type. The union
|
|
should be used to define easily accessible type for
|
|
events.</entry>
|
|
</row>
|
|
<row>
|
|
<entry>__u32</entry>
|
|
<entry><structfield>pending</structfield></entry>
|
|
<entry></entry>
|
|
<entry>Number of pending events excluding this one.</entry>
|
|
</row>
|
|
<row>
|
|
<entry>__u32</entry>
|
|
<entry><structfield>sequence</structfield></entry>
|
|
<entry></entry>
|
|
<entry>Event sequence number. The sequence number is
|
|
incremented for every subscribed event that takes place.
|
|
If sequence numbers are not contiguous it means that
|
|
events have been lost.
|
|
</entry>
|
|
</row>
|
|
<row>
|
|
<entry>struct timespec</entry>
|
|
<entry><structfield>timestamp</structfield></entry>
|
|
<entry></entry>
|
|
<entry>Event timestamp.</entry>
|
|
</row>
|
|
<row>
|
|
<entry>__u32</entry>
|
|
<entry><structfield>reserved</structfield>[9]</entry>
|
|
<entry></entry>
|
|
<entry>Reserved for future extensions. Drivers must set
|
|
the array to zero.</entry>
|
|
</row>
|
|
</tbody>
|
|
</tgroup>
|
|
</table>
|
|
|
|
</refsect1>
|
|
</refentry>
|
|
<!--
|
|
Local Variables:
|
|
mode: sgml
|
|
sgml-parent-document: "v4l2.sgml"
|
|
indent-tabs-mode: nil
|
|
End:
|
|
-->
|