Can not get the io_service_t object representing the device driver.

Dear,All
I want to send scsi command to my usb mass storage device from user space on Mac OS X . I modified the code from \"simpleUserClient\" . It works well with my single Lun mass storage device . But I can not work on the muti luns storage device. I can not get the io_service_t object representing the device driver . Did any one tell me why ? Thanks you in advance.



ClassToMatch = IOServiceMatching(kMyDriversIOKitClassName);

if (ClassToMatch)
{
    serviceObject = IOServiceGetMatchingService(masterPort,ClassToMatch);

   // Can not get serviceObject  if the USB Mass Storage Device has muti luns.
  

自己解决了!原来驱动有问题(MUTI_LUN没注册服务).