On 2012.05.22 10:14, Xiaofan Chen wrote: >> However, if Windows always considers a device with 0:0 in the device >> descriptor an error, then the Windows backend should discard them. > > I believe that Windows always considers a device with 0:0 in the device > descriptor as an error.
Yup. And the warning is how it indicates that the device is discarded. Oh and Peter, if you want to act like you want to provide insightful advice for libusbx users, the please try to bother looking at the code, as it would have answered your question. If you did, you'd have seen that a very explicit LIBUSB_ERROR_NO_DEVICE was returned when the warning occurs, meaning that any device that cannot obtain connection info is discarded. As to supporting devices with 0:0, I don't remember trying but I don't see much of any reason why it wouldn't work. The connection info error message is not a consequence of having a valid device with 0:0 as VID:PID, but rather the result of not having a device, with 0:0, that can actually be queried for its connection information By the way, we encountered the message over on libusb when we investigated the Renesas driver bug [1], which seemed to return an invalid device interface path (which also is the logical explanation for code 87, as the only parameter that can be invalid is the path). I'd be interested to see a full debug output to try to figure out when exactly this 0:0 device is generated. Regards, /Pete [1] http://marc.info/?l=libusb-devel&m=130934450111495&w=2 ------------------------------------------------------------------------------ Live Security Virtual Conference Exclusive live event will cover all the ways today's security and threat landscape has changed and how IT managers can respond. Discussions will include endpoint security, mobile security and the latest in malware threats. http://www.accelacomm.com/jaw/sfrnl04242012/114/50122263/ _______________________________________________ libusbx-devel mailing list libusbx-devel@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/libusbx-devel
