POBJECT_NAME_INFORMATION oni = NULL;

oni= (POBJECT_NAME_INFORMATION)malloc(256*sizeof(WCHAR));
          status = ZwQueryObject(hFile,
                     ObjectNameInformation,
                     oni,
                     256*sizeof(WCHAR),
                     &rt);

        WCHAR obj_name[256] = {0};
        RtlCopyMemory(obj_name,oni->Name.Buffer,oni->Name.Length);
        printf("%S\n",obj_name);

------------------------------------
\Device\Harddisk0\DR0

呵呵，谢谢指教了，内存分配错误导致执行失败！现在修正了，感谢哦！
type
  PUNICODE_STRING = ^UNICODE_STRING;
  _UNICODE_STRING = record
    Length: Word;
    MaximumLength: Word;
    Buffer: PWideChar;
  end;
  UNICODE_STRING = _UNICODE_STRING;
  PCUNICODE_STRING = ^UNICODE_STRING;
  TUnicodeString = UNICODE_STRING;
  PUnicodeString = PUNICODE_STRING;

type
  _OBJECT_NAME_INFORMATION = record
    Name: UNICODE_STRING;
  end;
  OBJECT_NAME_INFORMATION = _OBJECT_NAME_INFORMATION;
  POBJECT_NAME_INFORMATION = ^OBJECT_NAME_INFORMATION;
  TObjectNameInformation = OBJECT_NAME_INFORMATION;
  PObjectNameInformation = ^OBJECT_NAME_INFORMATION;

type
  _OBJECT_INFORMATION_CLASS = (
    ObjectBasicInformation,
    ObjectNameInformation,
    ObjectTypeInformation,
    ObjectAllTypesInformation,
    ObjectHandleInformation);
  OBJECT_INFORMATION_CLASS = _OBJECT_INFORMATION_CLASS;
  TObjectInformationClass = OBJECT_INFORMATION_CLASS;

function  ZwQueryObject(ObjectHandle: THANDLE; ObjectInformationClass: OBJECT_INFORMATION_CLASS; ObjectInformation: Pointer; ObjectInformationLength: ULONG; ReturnLength: PULONG): DWORD; stdcall; external 'ntdll.dll';

function GetNameByHandle(hFile: THANDLE):string;
var
  st,rt:dword;
  fsi:POBJECT_NAME_INFORMATION;
begin
  result := '';
  fsi:=GetMemory(256*2);
  st:=ZwQueryObject(
    hFile,
    ObjectNameInformation,
    fsi,
    256*2,
    @rt
  );
  if st=0 then Result:=fsi.Name.Buffer;
  FreeMemory(fsi);
end;