USBIO Driver for Windows CE - Thesycon Systemsoftware ...

3 Programming Interface
CUsbIo::GetDescriptor
Get a descriptor from the device.
Definition
DWORD
GetDescriptor(
void* Buffer,
DWORD& ByteCount,
USBIO_REQUEST_RECIPIENT Recipient,
UCHAR DescriptorType,
UCHAR DescriptorIndex = 0,
USHORT LanguageId = 0
);
Parameters
Buffer
Pointer to a caller-provided buffer. The buffer receives the requested descriptor.
ByteCount
When the function is called ByteCount specifies the size, in bytes, of the buffer pointed to
by Buffer. After the function successfully returned ByteCount contains the number of
valid bytes returned in the buffer.
Recipient
Specifies the recipient of the request. Possible values are enumerated by
USBIO_REQUEST_RECIPIENT.
DescriptorType
The type of the descriptor to request. Values are defined by the USB specification, chapter 9.
DescriptorIndex
The index of the descriptor to request. Set to zero if an index is not used for the descriptor
type, e.g. for a device descriptor.
LanguageId
The language ID of the descriptor to request. Used for string descriptors only. Set to zero if
not used.
Return Value
The function returns 0 if successful, an USBIO error code otherwise.
Comments
If the size of the provided buffer is less than the total size of the requested descriptor then only
the specified number of bytes from the beginning of the descriptor is returned.
44 USBIO Driver for Windows CE