On Sat, 2006-12-02 at 21:23 -0600, Jay Cliburn wrote: > I've seen references to this scattered about on the web, but no solutions. > > I installed FC6 on a Dell Inspiron 4000 laptop to use as a serial console for > debugging kernel problems. Whenever I start minicom on the laptop, however, I'm > greeted with a permission denied error to /dev/ttyS0. Sure enough, the perms on > ttyS0 are 0660 and I'm not a member of the uucp group: > > crw-rw---- 1 root uucp 4, 64 Dec 1 06:04 /dev/ttyS0 > crw-rw---- 1 root uucp 4, 65 Dec 1 06:03 /dev/ttyS1 > crw-rw---- 1 root uucp 4, 66 Dec 1 06:03 /dev/ttyS2 > crw-rw---- 1 root uucp 4, 67 Dec 1 06:03 /dev/ttyS3 > > No problem, I thought -- I'll just gin up a udev rule and set the perms to 0666. > Sorry; doesn't work. As a matter of fact, it gets worse: perms on ttyS0 go to > 0600 root:root as a result of my new local rule. > > Okay, not an ideal solution, but let's modify 50-udev.rules and set the default > rule for tty[A-Z]* to MODE="0666". Nope. Now they're *all* 0600 root:root. > > Here's the rule: > KERNEL=="ttyS0", NAME="%k", GROUP="uucp", MODE="0666" > > I had no problems with this under Debian Etch and Knoppix Live running on the > same laptop. Debian was running a 2.6.17 kernel, and for the life of me I can't > remember the Knoppix kernel version (the web site says 2.6.x -- big help), and I > don't have the CD here at home. > > The current workaround is to add non-root users to the uucp group. (Or maybe > this is the solution?) Any ideas why I can't get a udev rule to change the > perms to 0666 on /dev/ttyS0? > > Thanks, > Jay > > Why not solve the problem using the uucp group? It's the designed solution? - Gilboa
