The same here. seems to me that pacman trys to extract an directory while there is an file with the same name.

I didn't see this problem when I upgraded. Arjan, can you reproduce?

This is definitely persistent:
when i uninstall libusb there is nothing in /usr/lib which has to do with libusb-1.4.0. but after reinstall the same problem comes up:

[root@osirook lib]# pacman -Rc libusb

Targets: libusb sane libgphoto2 kdegraphics

Do you want to remove these packages? [Y/n] Y
removing libusb... done.
removing sane...
warning: /etc/hotplug/usb/libusbscanner saved as /etc/hotplug/usb/libusbscanner.pacsave
warning: /etc/hotplug/usb/libsane.usermap saved as /etc/hotplug/usb/libsane.usermap.pacsave
done.
removing libgphoto2... done.
removing kdegraphics... done.
[root@osirook lib]# pacman -S kdegraphics

Targets: libusb-0.1.8-3 sane-1.0.14-4 libgphoto2-2.1.4-1 kdegraphics-3.2.3-1

Proceed with upgrade? [Y/n] Y

checking package integrity... done.
loading package data... done.
checking for file conflicts... done.
installing libusb...
could not extract usr/lib/libusb-0.1.4: No such file or directory
errors occurred while installing libusb
done.
installing sane... done.
NOTE
----
If you use a usb scanner and hotplug than add your user to group 'scanner'
or change the /etc/hotplug/usb/libusbscanner to your needs. If your scanner
is not listed in /etc/hotplug/usb/libsane.usermap add a line for it.

If your usb scanner was turned on before booting, you have to unplug and
replug to access it as non root user. Or, you may add a line to your
/etc/rc.local file granting permissions when your system boots. Use the
'sane-find-scanner' command to obtain the correct path in the usb
filesystem. For example,

# sane-find-scanner | grep libusb
libusb:001:003
# echo "chmod a+rw /proc/bus/usb/001/003" >> /etc/rc.local

installing libgphoto2... done.
installing kdegraphics... done.

[root@osirook lib]#

This is always the same. even with a new download of libusb package. maybe the package itself is corrupt?

Arjan, a rebuild seems to fix this.

the problem is in PKGBUILD, with:
ln $startdir/pkg/usr/lib/libusb-0.1.4 $startdir/pkg/usr/lib/libusb-0.1.so.4
isnt it better to do a symlink:
ln -s $startdir/pkg/usr/lib/libusb-0.1.4 $startdir/pkg/usr/lib/libusb-0.1.so.4
?

Then there is no problem while upgrading. Building without ln -s gives the errormessage

even better, do it this way:

build() {
cd $startdir/src/$pkgname-$pkgver
./configure --prefix=/usr --disable-build-docs
make || return 1
make prefix=$startdir/pkg/usr install
# ln $startdir/pkg/usr/lib/libusb-0.1.4 $startdir/pkg/usr/lib/libusb-0.1.so.4
cd $startdir/pkg/usr/lib/
ln -s libusb-0.1.4 libusb-0.1.so.4
}

actually the latter fix is not correct. the problem does indeed lie in the symlink line and the likely culprit is the fact that we are now on libusb v1.8 and not 1.4. if this link indeed must be made then further investigation of the proper symlink line is required