failing to force-claim USB interface

[Martin F Krafft]

I am trying to make use of the usbfs USBDEVFS_DISCONNECT ioctl, and
I am failing. Here is the code:

  struct usb_device *dev;
  [...]
  sprintf(path, "/proc/bus/usb/%s/%s", dev->bus->dirname, dev->filename);
  int fd = open(path);
  struct usbdevfs_ioctl command = { 0, USBDEVFS_DISCONNECT, 0 };
  ioctl (fd, USBDEVFS_IOCTL, &command) < 0

However, the ioctl always fails. I am not sure whether I am using
the right values for the file descriptor passed to ioctl(), or what
the interface number (first parameter of usbdevfs_ioctl) is.

Maybe someone could offer me some advice or tell me to RTFM (but
please specify TM to FR).

Thanks,

-- 
Martin F. Krafft                Artificial Intelligence Laboratory
Ph.D. Student                   Department of Information Technology
Email: krafft@xxxxxxxx          University of Zurich
Tel: +41.(0)1.63-54323          Andreasstrasse 15, Office 2.20
http://ailab.ch/people/krafft   CH-8050 Zurich, Switzerland
 
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