7.44. ioctl VIDIOC_OVERLAY¶
VIDIOC_OVERLAY - Start or stop video overlay
ioctl(int fd, VIDIOC_OVERLAY, const int *argp)¶
This ioctl is part of the video overlay I/O method. Applications call ioctl VIDIOC_OVERLAY to start or stop the overlay. It takes a pointer to an integer which must be set to zero by the application to stop overlay, to one to start.
Drivers do not support ioctl VIDIOC_STREAMON, VIDIOC_STREAMOFF or
7.44.5. 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
Generic Error Codes chapter.
- The overlay parameters have not been set up. See Video Overlay Interface for the necessary steps.