Sebastian Friebe wrote: > That's exactly my problem. > I know there are some pointers in the C++ structure pointing to the > data inside the structure. But I don't have an idea at all, how to > port it to Python. > > Could you give me an example of a very basic SCSI command, like the > TEST_UNIT_READY ? >
I'm afraid I can't. I write Windows drivers for a living, so I do an awful lot of DeviceIoControl calls, but so far we have managed to avoid working the disk arena. > I didn't know if it would work, so I > started with a very strait forward approach. > I extracted the content of the SCSI_PASS_THROUGH in my C++ example > into a array of bytes. > I included the byte stream I found into my byte_list. > e.g. > > SCSI_TEST_UNIT_READY=[0x2C,0x00,0x00,0x00,0x01,0x00,0x06,0x18,0x02,0x00,0x00,0x00,0x00,0x00,0x00,0x00,\ > > 0x02,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x30,0x00,0x00,0x00,0x00,0x00,0x00,0x00,\ > > 0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,\ > > 0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,0x00,\ > 0x00,0x00,0x00,0x00] > The length says 0x2C, which is 44 decimal, but unless I have miscounted, there are 0x44 bytes of data there, which is 64 decimal. > byte_list = SCSI_TEST_UNIT_READY > > If the basic functionality is proven, I planned to go for a more > object oriented approach like: > > class SCSI_PASS_THROUGH_DIRECT(object): > def __init__(self, cdbLength = 16, transfer_length, transfer_direction): > self.Length = 0 # USHORT Length; > self.ScsiStatus = 0 # UCHAR > ScsiStatus; > I'm afraid that you will end up battling against the language here. I have three possible suggestions for you. 1. Consider using ctypes. ctypes includes mechanisms where you can build up C structures in a Pythonic way, almost exactly like you have done here. 2. Consider using SWIG. Swig will allow you to build a C or C++ DLL that can be called directly from Python. You could hide the pointer ugliness inside the C code, and still wrap it with a Python class. Swig is extraordinarily powerful, although there is a bit of a learning curve if you need to do anything unusual. There are lots of good example, however. 3. Consider using boost.python. If you know C++, the Boost libraries include a very good set of template classes that let you build Python object in C++ in a more natural way. Like option 2, this would let you put the sticky parts in C++ and the fun parts in Python. -- Tim Roberts, [EMAIL PROTECTED] Providenza & Boekelheide, Inc. _______________________________________________ python-win32 mailing list python-win32@python.org http://mail.python.org/mailman/listinfo/python-win32
