7.44. ioctl VIDIOC_OVERLAY¶
VIDIOC_OVERLAY - Start or stop video overlay
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.