Sakari Ailus | dd96608 | 2010-03-27 10:58:24 -0300 | [diff] [blame] | 1 | <refentry id="vidioc-dqevent"> |
| 2 | <refmeta> |
| 3 | <refentrytitle>ioctl VIDIOC_DQEVENT</refentrytitle> |
| 4 | &manvol; |
| 5 | </refmeta> |
| 6 | |
| 7 | <refnamediv> |
| 8 | <refname>VIDIOC_DQEVENT</refname> |
| 9 | <refpurpose>Dequeue event</refpurpose> |
| 10 | </refnamediv> |
| 11 | |
| 12 | <refsynopsisdiv> |
| 13 | <funcsynopsis> |
| 14 | <funcprototype> |
| 15 | <funcdef>int <function>ioctl</function></funcdef> |
| 16 | <paramdef>int <parameter>fd</parameter></paramdef> |
| 17 | <paramdef>int <parameter>request</parameter></paramdef> |
| 18 | <paramdef>struct v4l2_event |
| 19 | *<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_DQEVENT</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>Dequeue an event from a video device. No input is required |
| 53 | for this ioctl. All the fields of the &v4l2-event; structure are |
| 54 | filled by the driver. The file handle will also receive exceptions |
| 55 | which the application may get by e.g. using the select system |
| 56 | call.</para> |
| 57 | |
| 58 | <table frame="none" pgwide="1" id="v4l2-event"> |
| 59 | <title>struct <structname>v4l2_event</structname></title> |
| 60 | <tgroup cols="4"> |
| 61 | &cs-str; |
| 62 | <tbody valign="top"> |
| 63 | <row> |
| 64 | <entry>__u32</entry> |
| 65 | <entry><structfield>type</structfield></entry> |
| 66 | <entry></entry> |
| 67 | <entry>Type of the event.</entry> |
| 68 | </row> |
| 69 | <row> |
| 70 | <entry>union</entry> |
| 71 | <entry><structfield>u</structfield></entry> |
| 72 | <entry></entry> |
| 73 | <entry></entry> |
| 74 | </row> |
| 75 | <row> |
| 76 | <entry></entry> |
Hans Verkuil | 0e1de38 | 2010-03-27 14:10:57 -0300 | [diff] [blame] | 77 | <entry>&v4l2-event-vsync;</entry> |
| 78 | <entry><structfield>vsync</structfield></entry> |
| 79 | <entry>Event data for event V4L2_EVENT_VSYNC. |
| 80 | </entry> |
| 81 | </row> |
| 82 | <row> |
| 83 | <entry></entry> |
Sakari Ailus | dd96608 | 2010-03-27 10:58:24 -0300 | [diff] [blame] | 84 | <entry>__u8</entry> |
| 85 | <entry><structfield>data</structfield>[64]</entry> |
| 86 | <entry>Event data. Defined by the event type. The union |
| 87 | should be used to define easily accessible type for |
| 88 | events.</entry> |
| 89 | </row> |
| 90 | <row> |
| 91 | <entry>__u32</entry> |
| 92 | <entry><structfield>pending</structfield></entry> |
| 93 | <entry></entry> |
| 94 | <entry>Number of pending events excluding this one.</entry> |
| 95 | </row> |
| 96 | <row> |
| 97 | <entry>__u32</entry> |
| 98 | <entry><structfield>sequence</structfield></entry> |
| 99 | <entry></entry> |
| 100 | <entry>Event sequence number. The sequence number is |
| 101 | incremented for every subscribed event that takes place. |
| 102 | If sequence numbers are not contiguous it means that |
| 103 | events have been lost. |
| 104 | </entry> |
| 105 | </row> |
| 106 | <row> |
Hans Verkuil | 0e1de38 | 2010-03-27 14:10:57 -0300 | [diff] [blame] | 107 | <entry>struct timespec</entry> |
Sakari Ailus | dd96608 | 2010-03-27 10:58:24 -0300 | [diff] [blame] | 108 | <entry><structfield>timestamp</structfield></entry> |
| 109 | <entry></entry> |
| 110 | <entry>Event timestamp.</entry> |
| 111 | </row> |
| 112 | <row> |
| 113 | <entry>__u32</entry> |
| 114 | <entry><structfield>reserved</structfield>[9]</entry> |
| 115 | <entry></entry> |
| 116 | <entry>Reserved for future extensions. Drivers must set |
| 117 | the array to zero.</entry> |
| 118 | </row> |
| 119 | </tbody> |
| 120 | </tgroup> |
| 121 | </table> |
| 122 | |
| 123 | </refsect1> |
| 124 | </refentry> |
| 125 | <!-- |
| 126 | Local Variables: |
| 127 | mode: sgml |
| 128 | sgml-parent-document: "v4l2.sgml" |
| 129 | indent-tabs-mode: nil |
| 130 | End: |
| 131 | --> |