IOUSBHostInterestHandler
The callback that handles underlying service-state changes.
Declaration
typealias IOUSBHostInterestHandler = (IOUSBHostObject, UInt32, UnsafeMutableRawPointer?) -> VoidParameters
- hostObject:
The Iousbhostobject of the interest notification.
- messageType:
A
messageTypeenumeration thatIOKit/IOMessage.hor the Ioservice family defines. - messageArgument:
An argument for the message, dependent on the message type. If the message data is larger than
sizeof(void*),messageArgumentcontains a pointer to the message data; otherwise,messageArgumentcontains the message data.
Discussion
This is the block for the kIOGeneralInterest handler, and handles underlying service-state changes, such as termination. See IOServiceInterestCallback in IOKit for more details. An internal serial queue separate from the input/output queue services all notifications.