The stream handler device (SHD) messages are provided by a stream handler through a single entry point, SHDEntryPoint, to a physical device driver. For this interface, all pointers are 16:16 pointers; this enables the current 16-bit device-driver model to be used for stream handlers. There are two SHD messages. The message number must be used in the ulFunction field, of the parameter structure passed in the call, to indicate which message is being requested by the stream handler.
The following table lists the SHD messages:
┌────────┬────────────────────┬───────────────────────────────────┐ │Message │Message │Description │ │Number │ │ │ ├────────┼────────────────────┼───────────────────────────────────┤ │1L │SHD_REPORT_EVENT │Reports an event to the stream │ │ │ │handler. │ ├────────┼────────────────────┼───────────────────────────────────┤ │0L │SHD_REPORT_INT │Reports an interrupt from a device.│ └────────┴────────────────────┴───────────────────────────────────┘