SetIOOperationHandler
Sets the IOOperationHandler block on the device.
Declaration
kern_return_t SetIOOperationHandler(IOOperationHandler in_io_operation_block);Parameters
- in_io_operation_block:
The IOOperationHandler block to be called when the host performs an IO operation.
Return Value
kIOReturnSuccess if the IOOperationHandler block was successfuly set on the device
Discussion
The IOOperationHandler will be invoked when a IO operation is performed by the host. The handler will be called on a real time priority thread, so any work should only call real-time safe operations and never block. Many of the calls to various IOUserVideoObjects are syncrhonized against the work queue, so any necessary information to perform IO should be cached and captured in the block.