File descriptor returned by
Applications set the
of a struct v4l2_buffer to the same buffer type as previously
type and struct v4l2_requestbuffers
type, and the
field. Valid index numbers range from zero
to the number of buffers allocated with
count) minus one.
VIDIOC_QUERYBUF with a pointer to
this structure drivers return an error code or fill the rest of
flags field the
V4L2_BUF_FLAG_DONE flags will be valid. The
memory field will be set to
contains the offset of the buffer from the start of the device memory,
length field its size. The driver may
or may not set the remaining fields and flags, they are meaningless in
v4l2_buffer structure is
specified in Section 3.5.
On success 0 is returned, on error -1 and the
errno variable is set appropriately:
type is not
supported, or the
index is out of bounds.