The printer model I own is a Canon CX3200. because it is both a printer and a scanner, there are multiple conflicting udev rules for it. in the end udev rules change the permissions of /dev/usb/lp0 to crw-rw---- 1 root scanner which means that CUPS (or other non-root printing programs) cannot access the device. My personal fix was to change 99-libsane.rules thus: # EPSON CC-570L | EPSON Stylus CX3100 | EPSON Stylus CX3200 | Epson CX-3200 ATTRS{idVendor}=="04b8", ATTRS{idProduct}=="0802", MODE="666", GROUP="scanner" so the MODE is "666"6 instead of "660" I was unable to correct this with out changing udev rules. i even tried making lp a member of the scanner group. I am certain my model can't be the only one affected by this issue Reproducible: Always Steps to Reproduce: 1. plug in Multifunction Printer 2. check owner, group and permissions on /dev/usb/lp0 3. Try to print. CUPS can see the printer and reports it is ready, but no jobs ever get printed Actual Results: pterodactyl ~ # ls -l /dev/usb/lp0 crw-rw-rw- 1 root scanner 180, 0 2007-09-20 17:21 /dev/usb/lp0 CUPS never prints. Expected Results: either permission crw-rw-rw- OR owner root:lp crw-rw---- and cups able to print This bug make hardware that functions with CUPS nonfunctional as soon as you emerge any sane variant.
Please attach 1. udevinfo -a --name=/dev/usb/lp0 2. emerge --info 3. The version numbers of udev and libsane.
It looks like a SANE issue to me... CCing the SANE maintainer
Created attachment 131912 [details] the resuls of running udevinfo -a --name=/dev/usb/lp0
media-gfx/sane-backends-1.0.18-r4 media-gfx/xsane-0.994 sys-fs/udev-114 net-print/cups-1.2.10-r1
(In reply to comment #4) > media-gfx/sane-backends-1.0.18-r4 > media-gfx/xsane-0.994 > sys-fs/udev-114 > net-print/cups-1.2.10-r1 > Well, the rules sane-backends-1.0.18-r4 installs here begin like this: + ACTION!="add", GOTO="libsane_rules_end" This matches on add event. + SUBSYSTEMS=="scsi", ATTRS{type}=="6", MODE="660", GROUP="scanner" This does not match. + SUBSYSTEM!="usb|usb_device", GOTO="libsane_rules_end" This matches on our lp0 device, as it also has SUBSYSTEM==usb :( Looking at package iscan gives an idea how to solve this. Please add this rule after the SUBSYSTEM check: KERNEL=="lp[0-9]*", GOTO="libsane_rules_end"
Does this rule also work (instead of the one from Comment #5): SUBSYSTEM=="usb", ENV{DEVTYPE}!="usb_device", GOTO="libsane_rules_end"
inserted the line in comment 6 at the end of the other SUBSYSTEM rules. Works for me. pterodactyl daddio # ls -l /dev/usb total 0 crw-rw---- 1 root lp 180, 0 2007-09-29 08:01 lp0 Both CUPS and xsane work after running udevstart THANKS!
Added sane-backends-1.0.18-r5 that contains this fixed rule.
*** Bug 215241 has been marked as a duplicate of this bug. ***
As I pointed out in https://bugs.gentoo.org/show_bug.cgi?id=215241, it is also possible to add the line Group scanner in /etc/cups/cupsd.conf to force CUPS to send print jobs with the "right" permissions. If you want to wait for sane-backends-1.0.18-r5 to be marked as stable or don't want to edit udev rules, it is a very quick workaround.
As sane-backends-1.0.18-r6 is now marked sable, I report here that it works for me.
