Hello,

I apologize if this has already been discussed.  The
sourceforge page with the archive for this mailing list
seems to be down.

Apparently libusb silently ignores at least some permission
errors, and there is nothing in the API which allows such
errors to be reported back to applications.  As a result
applications, like lsusb, which report on usb devices must be
run as root lest some devices be silently omitted from
the report.

I can understand having some devices be entirely invisible,
as are files in a directory to which the user has no
permissions, but that is not the case here.  The devices
are visible in the /proc or /dev filesystems, presumably
because the usb bus itself, which plays a role similar
to a directory, is always readable.  Applications should
be able to deliver informative error messages regarding
permissions rather than behaving as if the device
does not exist.

I understand that this is not a problem which can be
immediately resolved.  I write to be sure that t
his problem is not forever unnoticed
and unresolved.  Whatever design is chosen it would be nice
if it was consistent with the pci bus interface.  (FYI,
lspci(8) says:

       Access  to  some  parts of the PCI
       configuration space is restricted to
       root on many operating systems, so
       the features of lspci  available  to
       normal  users  are limited. However,
       lspci tries its best to display as
       much as available and mark all other
       information with  <access  denied>
       text.
)

See Debian Bug #440763 for more detail than is comfortable.
http://bugs.debian.org/cgi-bin/bugreport.cgi?bug=440763

Regards,

Karl <[EMAIL PROTECTED]>
Free Software:  "You don't pay back, you pay forward."
                 -- Robert A. Heinlein


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