63 lines
1.5 KiB
ReStructuredText
63 lines
1.5 KiB
ReStructuredText
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.. -*- coding: utf-8; mode: rst -*-
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.. _vidioc-overlay:
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********************
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ioctl VIDIOC_OVERLAY
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********************
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*man VIDIOC_OVERLAY(2)*
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Start or stop video overlay
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Synopsis
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========
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.. c:function:: int ioctl( int fd, int request, const int *argp )
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Arguments
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=========
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``fd``
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File descriptor returned by :ref:`open() <func-open>`.
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``request``
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VIDIOC_OVERLAY
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``argp``
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Description
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===========
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This ioctl is part of the :ref:`video overlay <overlay>` I/O method.
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Applications call ``VIDIOC_OVERLAY`` to start or stop the overlay. It
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takes a pointer to an integer which must be set to zero by the
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application to stop overlay, to one to start.
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Drivers do not support :ref:`VIDIOC_STREAMON <vidioc-streamon>` or
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:ref:`VIDIOC_STREAMOFF <vidioc-streamon>` with
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``V4L2_BUF_TYPE_VIDEO_OVERLAY``.
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Return Value
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============
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On success 0 is returned, on error -1 and the ``errno`` variable is set
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appropriately. The generic error codes are described at the
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:ref:`Generic Error Codes <gen-errors>` chapter.
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EINVAL
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The overlay parameters have not been set up. See :ref:`overlay`
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for the necessary steps.
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.. ------------------------------------------------------------------------------
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.. This file was automatically converted from DocBook-XML with the dbxml
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.. library (https://github.com/return42/sphkerneldoc). The origin XML comes
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.. from the linux kernel, refer to:
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..
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.. * https://github.com/torvalds/linux/tree/master/Documentation/DocBook
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.. ------------------------------------------------------------------------------
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