[Nut-upsdev] More information on USB bus

[Arjen de Korte]

When I plug in a device, the kernel will not only tell me to which USB
bus it is connected, but also the socket it is plugged into:

> Aug 31 22:06:07 miffy kernel: usb 1-1: new low speed USB device using uhci_hcd and address 31
> Aug 31 22:06:08 miffy kernel: usb 1-1: new device found, idVendor=0463, idProduct=ffff
> Aug 31 22:06:08 miffy kernel: usb 1-1: new device strings: Mfr=1, Product=2, SerialNumber=3
> Aug 31 22:06:08 miffy kernel: usb 1-1: Product: Evolution
> Aug 31 22:06:08 miffy kernel: usb 1-1: Manufacturer: MGE UPS SYSTEMS
> Aug 31 22:06:08 miffy kernel: usb 1-1: SerialNumber: AV1H2402G
> Aug 31 22:06:08 miffy kernel: usb 1-1: configuration #1 chosen from 1 choice

On USB bus 1, I have two sockets and it clearly makes a difference in
which I put the connector. The kernel will report either 'usb 1-1' or
'usb 1-2'. Is there a way to get to this information through libusb?