iokit/Kernel/IOUserClient.cpp

504                               void * messageArgument, vm_size_t argSize );
507                               void * messageArgument, vm_size_t argSize );
784                                             void * argument, vm_size_t argSize )
787                                 ref, messageType, provider, argument, argSize));
792                                     void * messageArgument, vm_size_t argSize )
808     if( argSize == 0)
812 	    argSize = sizeof(data->messageArgument[0]);
816 	    argSize = sizeof(uint32_t);
821         if( argSize > kIOUserNotifyMaxMessageSize)
822             argSize = kIOUserNotifyMaxMessageSize;
823         bcopy( messageArgument, data->messageArgument, argSize );
828         + argSize;