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Diffstat (limited to 'Documentation/DocBook/media/v4l/vidioc-g-priority.xml')
-rw-r--r-- | Documentation/DocBook/media/v4l/vidioc-g-priority.xml | 135 |
1 files changed, 0 insertions, 135 deletions
diff --git a/Documentation/DocBook/media/v4l/vidioc-g-priority.xml b/Documentation/DocBook/media/v4l/vidioc-g-priority.xml deleted file mode 100644 index 6a81b4fe9538..000000000000 --- a/Documentation/DocBook/media/v4l/vidioc-g-priority.xml +++ /dev/null @@ -1,135 +0,0 @@ -<refentry id="vidioc-g-priority"> - <refmeta> - <refentrytitle>ioctl VIDIOC_G_PRIORITY, VIDIOC_S_PRIORITY</refentrytitle> - &manvol; - </refmeta> - - <refnamediv> - <refname>VIDIOC_G_PRIORITY</refname> - <refname>VIDIOC_S_PRIORITY</refname> - <refpurpose>Query or request the access priority associated with a -file descriptor</refpurpose> - </refnamediv> - - <refsynopsisdiv> - <funcsynopsis> - <funcprototype> - <funcdef>int <function>ioctl</function></funcdef> - <paramdef>int <parameter>fd</parameter></paramdef> - <paramdef>int <parameter>request</parameter></paramdef> - <paramdef>enum v4l2_priority *<parameter>argp</parameter></paramdef> - </funcprototype> - </funcsynopsis> - <funcsynopsis> - <funcprototype> - <funcdef>int <function>ioctl</function></funcdef> - <paramdef>int <parameter>fd</parameter></paramdef> - <paramdef>int <parameter>request</parameter></paramdef> - <paramdef>const enum v4l2_priority *<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_PRIORITY, VIDIOC_S_PRIORITY</para> - </listitem> - </varlistentry> - <varlistentry> - <term><parameter>argp</parameter></term> - <listitem> - <para>Pointer to an enum v4l2_priority type.</para> - </listitem> - </varlistentry> - </variablelist> - </refsect1> - - <refsect1> - <title>Description</title> - - <para>To query the current access priority -applications call the <constant>VIDIOC_G_PRIORITY</constant> ioctl -with a pointer to an enum v4l2_priority variable where the driver stores -the current priority.</para> - - <para>To request an access priority applications store the -desired priority in an enum v4l2_priority variable and call -<constant>VIDIOC_S_PRIORITY</constant> ioctl with a pointer to this -variable.</para> - - <table frame="none" pgwide="1" id="v4l2-priority"> - <title>enum v4l2_priority</title> - <tgroup cols="3"> - &cs-def; - <tbody valign="top"> - <row> - <entry><constant>V4L2_PRIORITY_UNSET</constant></entry> - <entry>0</entry> - <entry></entry> - </row> - <row> - <entry><constant>V4L2_PRIORITY_BACKGROUND</constant></entry> - <entry>1</entry> - <entry>Lowest priority, usually applications running in -background, for example monitoring VBI transmissions. A proxy -application running in user space will be necessary if multiple -applications want to read from a device at this priority.</entry> - </row> - <row> - <entry><constant>V4L2_PRIORITY_INTERACTIVE</constant></entry> - <entry>2</entry> - <entry></entry> - </row> - <row> - <entry><constant>V4L2_PRIORITY_DEFAULT</constant></entry> - <entry>2</entry> - <entry>Medium priority, usually applications started and -interactively controlled by the user. For example TV viewers, Teletext -browsers, or just "panel" applications to change the channel or video -controls. This is the default priority unless an application requests -another.</entry> - </row> - <row> - <entry><constant>V4L2_PRIORITY_RECORD</constant></entry> - <entry>3</entry> - <entry>Highest priority. Only one file descriptor can have -this priority, it blocks any other fd from changing device properties. -Usually applications which must not be interrupted, like video -recording.</entry> - </row> - </tbody> - </tgroup> - </table> - </refsect1> - - <refsect1> - &return-value; - - <variablelist> - <varlistentry> - <term><errorcode>EINVAL</errorcode></term> - <listitem> - <para>The requested priority value is invalid.</para> - </listitem> - </varlistentry> - <varlistentry> - <term><errorcode>EBUSY</errorcode></term> - <listitem> - <para>Another application already requested higher -priority.</para> - </listitem> - </varlistentry> - </variablelist> - </refsect1> -</refentry> |