[Lprof-users] usb device permissions

[Kai-Uwe B. <ku...@gm...>]

Hello,

I'd liked to profile a monitor with LProf, but had less success.
The attached error dialog poped up while accessing the measurement device.
My difficulty was not so much that permissions are not perfect. I had 
rather spent a lot of time to find out, which file in the system I have to 
chmod to 0666.
So frankly the location in the information window was useless to me:
usb:/bus/0/dev - where is this in the system?
After a while searching the archives and with the help of lsusb I found: 
/dev/bus/usb/002/009, umm.

I know that the linux usb/permission system is a pure mess. E.g. many 
devices are mapped to some file but then this file is not communicated 
correctly. But with a little more verbose message in LProf, I would have 
been able to circumvent that quickly. Something like
... usb:/bus/0/dev (file:///dev/bus/usb/002/009) ...


kind regards
Kai-Uwe Behrmann
-- 
developing for colour management 
www.behrmann.name + www.oyranos.org