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+.. Permission is granted to copy, distribute and/or modify this
+.. document under the terms of the GNU Free Documentation License,
+.. Version 1.1 or any later version published by the Free Software
+.. Foundation, with no Invariant Sections, no Front-Cover Texts
+.. and no Back-Cover Texts. A copy of the license is included at
+.. Documentation/userspace-api/media/fdl-appendix.rst.
+..
+.. TODO: replace it to GFDL-1.1-or-later WITH no-invariant-sections
+
+.. _VIDIOC_OVERLAY:
+
+********************
+ioctl VIDIOC_OVERLAY
+********************
+
+Name
+====
+
+VIDIOC_OVERLAY - Start or stop video overlay
+
+
+Synopsis
+========
+
+.. c:function:: int ioctl( int fd, VIDIOC_OVERLAY, const int *argp )
+    :name: VIDIOC_OVERLAY
+
+
+Arguments
+=========
+
+``fd``
+    File descriptor returned by :ref:`open() <func-open>`.
+
+``argp``
+    Pointer to an integer.
+
+
+Description
+===========
+
+This ioctl is part of the :ref:`video overlay <overlay>` I/O method.
+Applications call :ref:`VIDIOC_OVERLAY` to start or stop the overlay. It
+takes a pointer to an integer which must be set to zero by the
+application to stop overlay, to one to start.
+
+Drivers do not support :ref:`VIDIOC_STREAMON` or
+:ref:`VIDIOC_STREAMOFF <VIDIOC_STREAMON>` with
+``V4L2_BUF_TYPE_VIDEO_OVERLAY``.
+
+
+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 overlay parameters have not been set up. See :ref:`overlay`
+    for the necessary steps.