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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/media/uapi/fdl-appendix.rst.
-..
-.. TODO: replace it to GFDL-1.1-or-later WITH no-invariant-sections
-
-.. _VIDIOC_QUERYBUF:
-
-*********************
-ioctl VIDIOC_QUERYBUF
-*********************
-
-Name
-====
-
-VIDIOC_QUERYBUF - Query the status of a buffer
-
-
-Synopsis
-========
-
-.. c:function:: int ioctl( int fd, VIDIOC_QUERYBUF, struct v4l2_buffer *argp )
- :name: VIDIOC_QUERYBUF
-
-
-Arguments
-=========
-
-``fd``
- File descriptor returned by :ref:`open() <func-open>`.
-
-``argp``
- Pointer to struct :c:type:`v4l2_buffer`.
-
-
-Description
-===========
-
-This ioctl is part of the :ref:`streaming <mmap>` I/O method. It can
-be used to query the status of a buffer at any time after buffers have
-been allocated with the :ref:`VIDIOC_REQBUFS` ioctl.
-
-Applications set the ``type`` field of a struct
-:c:type:`v4l2_buffer` to the same buffer type as was
-previously used with struct :c:type:`v4l2_format` ``type``
-and struct :c:type:`v4l2_requestbuffers` ``type``,
-and the ``index`` field. Valid index numbers range from zero to the
-number of buffers allocated with
-:ref:`VIDIOC_REQBUFS` (struct
-:c:type:`v4l2_requestbuffers` ``count``) minus
-one. The ``reserved`` and ``reserved2`` fields must be set to 0. When
-using the :ref:`multi-planar API <planar-apis>`, the ``m.planes``
-field must contain a userspace pointer to an array of struct
-:c:type:`v4l2_plane` and the ``length`` field has to be set
-to the number of elements in that array. After calling
-:ref:`VIDIOC_QUERYBUF` with a pointer to this structure drivers return an
-error code or fill the rest of the structure.
-
-In the ``flags`` field the ``V4L2_BUF_FLAG_MAPPED``,
-``V4L2_BUF_FLAG_PREPARED``, ``V4L2_BUF_FLAG_QUEUED`` and
-``V4L2_BUF_FLAG_DONE`` flags will be valid. The ``memory`` field will be
-set to the current I/O method. For the single-planar API, the
-``m.offset`` contains the offset of the buffer from the start of the
-device memory, the ``length`` field its size. For the multi-planar API,
-fields ``m.mem_offset`` and ``length`` in the ``m.planes`` array
-elements will be used instead and the ``length`` field of struct
-:c:type:`v4l2_buffer` is set to the number of filled-in
-array elements. The driver may or may not set the remaining fields and
-flags, they are meaningless in this context.
-
-The struct :c:type:`v4l2_buffer` structure is specified in
-:ref:`buffer`.
-
-
-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 buffer ``type`` is not supported, or the ``index`` is out of
- bounds.