summaryrefslogtreecommitdiffstats
path: root/Documentation/DocBook/v4l/vidioc-dqevent.xml
diff options
context:
space:
mode:
Diffstat (limited to 'Documentation/DocBook/v4l/vidioc-dqevent.xml')
-rw-r--r--Documentation/DocBook/v4l/vidioc-dqevent.xml131
1 files changed, 131 insertions, 0 deletions
diff --git a/Documentation/DocBook/v4l/vidioc-dqevent.xml b/Documentation/DocBook/v4l/vidioc-dqevent.xml
new file mode 100644
index 00000000000..4e0a7cc3081
--- /dev/null
+++ b/Documentation/DocBook/v4l/vidioc-dqevent.xml
@@ -0,0 +1,131 @@
+<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:
+-->