On Tuesday 02 May 2006 17:40, m. allan noah wrote: > i am confused by this- first you say that you need sane to look under > /sys or /dev for devices, then you say that you have to alter permissions > to get it working. which is it?
udev mounts the usbscanner under /sys In my case, under /sys/bus/usb/ and then a randomly variable point. However, given the relevant vendor and product IDs, it will automatically create a symlink in /dev and set all the relevant permissions. So for example, I can make it produce a /dev/usbscanner symlink that will always point to the scanner, wherever it may have appeared on the /sys/bus/usb/ directory, and have the right permissions. However, sane appears to be looking for the scanner under /proc/bus/usb/whatever, which udev cannot easily (as far as I can see) set the permissions. As in the /sys file system, it seems to be somewhat random where it pops up, from one reboot to the next, although the location does correspond to the location under /sys. Even hotplug was incapable of setting the permissions automatically, because although my scanner always appeared as /proc/bus/usb/002/002, hotplug *always* tried to set the permissions for /proc/bus /usb/001/002! This was a bug in hotplug that never got fixed! I bypassed it by adding chown root:users /proc/bus/usb/002/002 chmod 0660 /proc/bus/usb/002/002 to my rc.local file. However, this only works if the scanner always appears on /proc/bus/usb/002/002 Under udev alone, it doesn't. As often as not it appears as /proc/bus/usb/001/003 or even something else! I need to find some way of making sane use /dev/usbscanner to access the scanner rather than /proc/bus/usb/whatever. My understanding is that this is a very old way of doing things that only works with kernel scanner modules. Certainly my initial attempts in this area have met with total failure! -- Pete chri...@attglobal.net
