Re: [Libusb-devel] libusb-1.0 doesn't find usb devices

[Alan S. <st...@ro...>]

On Mon, 6 Apr 2009, Peter Stuge wrote:

> Hi,
> 
> Alan Stern wrote:
> > > > Why it is that libusb-1.0 can't find these files
> > > 
> > > The default mount point (and name) for usbfs has changed over time.
> > 
> > This is not true.  The default mount point has always been
> > /proc/bus/usb.  Some distributions may choose to mount a usbfs
> > filesystem somewhere else; that's their business.  If they do then
> > they should make the corresponding changes to the version of libusb
> > they distribute.
> 
> Yep. I was thinking about how the device nodes are created in
> /dev/bus/usb/ by udev these days, and confused that with usbfs.
> Thanks for clearing it up. (The major difference is that usbfs has a
> devices file with info about all devices, and /dev/bus/usb does not.)

That's exactly right.

To add to the confusion, the kernel's implementation of those device
nodes uses a lot of the same code as its implementation of the usbfs
device files (as you would expect, since the nodes and the files do
essentially the same things).  So to a kernel programmer, it all looks
like just plain usbfs!  :-)

Alan Stern