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+.. -*- coding: utf-8; mode: rst -*-
+
+.. _VIDIOC_G_PRIORITY:
+
+******************************************
+ioctl VIDIOC_G_PRIORITY, VIDIOC_S_PRIORITY
+******************************************
+
+Name
+====
+
+VIDIOC_G_PRIORITY - VIDIOC_S_PRIORITY - Query or request the access priority associated with a file descriptor
+
+
+Synopsis
+========
+
+.. cpp:function:: int ioctl( int fd, int request, enum v4l2_priority *argp )
+
+.. cpp:function:: int ioctl( int fd, int request, const enum v4l2_priority *argp )
+
+
+Arguments
+=========
+
+``fd``
+    File descriptor returned by :ref:`open() <func-open>`.
+
+``request``
+    VIDIOC_G_PRIORITY, VIDIOC_S_PRIORITY
+
+``argp``
+    Pointer to an enum v4l2_priority type.
+
+
+Description
+===========
+
+To query the current access priority applications call the
+:ref:`VIDIOC_G_PRIORITY <VIDIOC_G_PRIORITY>` ioctl with a pointer to an enum v4l2_priority
+variable where the driver stores the current priority.
+
+To request an access priority applications store the desired priority in
+an enum v4l2_priority variable and call :ref:`VIDIOC_S_PRIORITY <VIDIOC_G_PRIORITY>` ioctl
+with a pointer to this variable.
+
+
+.. _v4l2-priority:
+
+.. flat-table:: enum v4l2_priority
+    :header-rows:  0
+    :stub-columns: 0
+    :widths:       3 1 4
+
+
+    -  .. row 1
+
+       -  ``V4L2_PRIORITY_UNSET``
+
+       -  0
+
+       -
+
+    -  .. row 2
+
+       -  ``V4L2_PRIORITY_BACKGROUND``
+
+       -  1
+
+       -  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.
+
+    -  .. row 3
+
+       -  ``V4L2_PRIORITY_INTERACTIVE``
+
+       -  2
+
+       -
+
+    -  .. row 4
+
+       -  ``V4L2_PRIORITY_DEFAULT``
+
+       -  2
+
+       -  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.
+
+    -  .. row 5
+
+       -  ``V4L2_PRIORITY_RECORD``
+
+       -  3
+
+       -  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.
+
+
+Return Value
+============
+
+On success 0 is returned, on error -1 and the ``errno`` variable is set
+appropriately. The generic error codes are described at the
+:ref:`Generic Error Codes <gen-errors>` chapter.
+
+EINVAL
+    The requested priority value is invalid.
+
+EBUSY
+    Another application already requested higher priority.