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Diffstat (limited to 'Documentation/media/uapi/v4l/mmap.rst')
| -rw-r--r-- | Documentation/media/uapi/v4l/mmap.rst | 31 |
1 files changed, 19 insertions, 12 deletions
diff --git a/Documentation/media/uapi/v4l/mmap.rst b/Documentation/media/uapi/v4l/mmap.rst index 670596c1a4f7..c47708bf2c87 100644 --- a/Documentation/media/uapi/v4l/mmap.rst +++ b/Documentation/media/uapi/v4l/mmap.rst @@ -1,4 +1,11 @@ -.. -*- coding: utf-8; mode: rst -*- +.. 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/media/uapi/fdl-appendix.rst. +.. +.. TODO: replace it to GFDL-1.1-or-later WITH no-invariant-sections .. _mmap: @@ -231,17 +238,17 @@ up the output is started with :ref:`VIDIOC_STREAMON <VIDIOC_STREAMON>`. In the write loop, when the application runs out of free buffers, it must wait until an empty buffer can be dequeued and reused. -To enqueue and dequeue a buffer applications use the :ref:`VIDIOC_QBUF` -and :ref:`VIDIOC_DQBUF <VIDIOC_QBUF>` ioctl. The status of a buffer -being mapped, enqueued, full or empty can be determined at any time -using the :ref:`VIDIOC_QUERYBUF` ioctl. Two methods exist to suspend -execution of the application until one or more buffers can be dequeued. -By default :ref:`VIDIOC_DQBUF <VIDIOC_QBUF>` blocks when no buffer is -in the outgoing queue. When the ``O_NONBLOCK`` flag was given to the -:ref:`open() <func-open>` function, :ref:`VIDIOC_DQBUF <VIDIOC_QBUF>` -returns immediately with an ``EAGAIN`` error code when no buffer is -available. The :ref:`select() <func-select>` or :ref:`poll() -<func-poll>` functions are always available. +To enqueue and dequeue a buffer applications use the +:ref:`VIVIOC_QBUF <VIDIOC_QBUF>` and :ref:`VIDIOC_DQBUF <VIDIOC_QBUF>` +ioctl. The status of a buffer being mapped, enqueued, full or empty can +be determined at any time using the :ref:`VIDIOC_QUERYBUF` ioctl. Two +methods exist to suspend execution of the application until one or more +buffers can be dequeued. By default :ref:`VIDIOC_DQBUF <VIDIOC_QBUF>` +blocks when no buffer is in the outgoing queue. When the ``O_NONBLOCK`` +flag was given to the :ref:`open() <func-open>` function, +:ref:`VIDIOC_DQBUF <VIDIOC_QBUF>` returns immediately with an ``EAGAIN`` +error code when no buffer is available. The :ref:`select() <func-select>` +or :ref:`poll() <func-poll>` functions are always available. To start and stop capturing or output applications call the :ref:`VIDIOC_STREAMON <VIDIOC_STREAMON>` and :ref:`VIDIOC_STREAMOFF |