How to retrieve iManufacturer/iProduct information from libusb20?

[Jack Twilley]

Hans Petter Selasky wrote:
> On Sunday 07 June 2009 04:45:20 Jack Twilley 
> wrote:
>> I have been looking through the source to 
> usbconfig and other tools
>> trying to figure out how to retrieve the 
> iManufacturer and iProduct
>> strings.  The libusb20 man page describes the
>> libusb20_dev_get_device_desc() function but 
> there's no useful
>> information on the struct it returns.  The 
> include file looks as if the
>> struct is automagically generated by macros 
> within macros which is too
>> complicated for me to figure out without 
> help.  Any ideas?  There's
>> gotta be a better way than using 
> LIBUSB20_DEVICE_DESC()...
> 
> After you find the string index, you can use the 
> following function to get strings:
> 
>      int
>      libusb20_dev_req_string_simple_sync(struct 
> libusb20_device *pdev,
>          uint8_t index, void *ptr, uint16_t len);

Finding the string index was harder than I expected, since I can't get 
anything useful out of what libusb20_dev_get_device_desc() returns. 
Heck, I even tried a short for loop from 0 to 15 just to see if the 
values I saw in usbconfig were magic values pointing to the string.

How do I find the string index?

> 
> 
> --HPS

Thanks!

Jack.