VIDIOC_DQEVENT — Dequeue event
int ioctl( | int fd, |
| int request, | |
struct v4l2_event
*argp); |
Dequeue an event from a video device. No input is required for this ioctl. All the fields of the struct 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.
Table A.10. struct v4l2_event
| __u32 | type | Type of the event. | |
| union | u | ||
| struct v4l2_event_vsync | vsync | Event data for event V4L2_EVENT_VSYNC. | |
| __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 | reserved[9] | Reserved for future extensions. Drivers must set the array to zero. |