ioctl VIDIOC_DQEVENT
&manvol;
VIDIOC_DQEVENT
Dequeue event
int ioctl
int fd
int request
struct v4l2_event
*argp
Arguments
fd
&fd;
request
VIDIOC_DQEVENT
argp
Description
Dequeue an event from a video device. No input is required
for this ioctl. All the fields of the &v4l2-event; structure are
filled by the driver. The file handle will also receive exceptions
which the application may get by e.g. using the select system
call.
struct v4l2_event
&cs-str;
__u32
type
Type of the event.
union
u
&v4l2-event-vsync;
vsync
Event data for event V4L2_EVENT_VSYNC.
&v4l2-event-ctrl;
ctrl
Event data for event V4L2_EVENT_CTRL.
__u8
data[64]
Event data. Defined by the event type. The union
should be used to define easily accessible type for
events.
__u32
pending
Number of pending events excluding this one.
__u32
sequence
Event sequence number. The sequence number is
incremented for every subscribed event that takes place.
If sequence numbers are not contiguous it means that
events have been lost.
struct timespec
timestamp
Event timestamp.
u32
id
The ID associated with the event source. If the event does not
have an associated ID (this depends on the event type), then this
is 0.
__u32
reserved[8]
Reserved for future extensions. Drivers must set
the array to zero.
&return-value;