IRP Function Codes
Microsoft Windows use I/O Request Packets (IRPs) to send messages to device drivers. An IRP is a data structure that contains specific information used to convey the status of an event. For more information about the IRP data structure, see IRP.
Your driver can use System-Supplied Driver Interfaces to send IRPs to other drivers.
In addition to the Standard IRP Codes, there are three additional types of IRPs for specific technologies:
Plug and Play IRPs
Power Management IRPs
Windows Management Instrumentation (WMI) IRPs
Build date: 12/5/2013