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+.. SPDX-License-Identifier: GFDL-1.1-no-invariants-or-later
+.. c:namespace:: V4L
+
+.. _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
+========
+
+.. c:macro:: VIDIOC_G_PRIORITY
+
+``int ioctl(int fd, VIDIOC_G_PRIORITY, enum v4l2_priority *argp)``
+
+.. c:macro:: VIDIOC_S_PRIORITY
+
+``int ioctl(int fd, VIDIOC_S_PRIORITY, const enum v4l2_priority *argp)``
+
+Arguments
+=========
+
+``fd``
+    File descriptor returned by :c:func:`open()`.
+
+``argp``
+    Pointer to an enum :c:type:`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.
+
+.. c:type:: v4l2_priority
+
+.. tabularcolumns:: |p{6.6cm}|p{2.2cm}|p{8.7cm}|
+
+.. flat-table:: enum v4l2_priority
+    :header-rows:  0
+    :stub-columns: 0
+    :widths:       3 1 4
+
+    * - ``V4L2_PRIORITY_UNSET``
+      - 0
+      -
+    * - ``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.
+    * - ``V4L2_PRIORITY_INTERACTIVE``
+      - 2
+      -
+    * - ``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.
+    * - ``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.