According to /lib/udev/rules.d/85-usbmuxd.rules usbmuxd is started with /usr/sbin/usbmuxd -u -U usbmux and 'id usbmux' shows uid=113(usbmux) gid=85(usb) grupy=85(usb) Yet I still get libusb couldn't open USB device /dev/bus/usb/001/006: Permission denied. libusb requires write access to USB device nodes. If -U is changed to -U my_user or omitted, everything works just fine.
*** Bug 323119 has been marked as a duplicate of this bug. ***
The problem can be solved by adding 'usbmux' user to 'plugdev' group. The relevant ebuild's line is enewuser usbmux -1 -1 -1 "usb" but simply adding ",plugdev" here doesn't seem to work for an already existing user. (Thanks to 'toberonenz' from the Gentoo Forums)
>The problem can be solved by adding 'usbmux' user to 'plugdev' group. >The relevant ebuild's line is > enewuser usbmux -1 -1 -1 "usb" >but simply adding ",plugdev" here doesn't seem to work for an already existing >user. usbmux must also belong to the usb group. If added to both groups it works.
+ 29 Jul 2010; Pacho Ramos <pacho@gentoo.org> usbmuxd-1.0.4.ebuild, + metadata.xml: + usbmux user needs to be in plugdev group also as reported in bug #323329. + Chainsaw doesn't want to maintain this any longer. But systems where the user is already created will probably need to manually add it to plugdev and usb groups manually
