On Thu, 2009-03-26 at 10:04 -0500, sv1cdn wrote: > vitamin wrote: > > Check permissions on /dev/ttyS0. One of the latest updates had something to do with HAL(dbus) default permissions. > > Thank you! Could you help me a bit more, I am kind of new. In /dev/ you want me to get an ls -la for ttyS0 ? > The following has been tested for Fedora 8 but should also work with any Linux distro that uses udev to manage devices or runs the contents of the /etc/rc.d/rc.local script during the boot process. The problem was that the standard serial ports /dev/ttyS* and the USB serial ports /dev/ttyUSB* are owned by root and by default only give read and write access to their owner and the 'uucp' group. This means that a normal user can't run programs that access them. I know two solutions: 1) The kludge. Add the command chmod uga+rw /dev/tty[A-Z]* into /etc/rd.d/rc.local By default this script is run as part of the boot process but contains nothing except comments saying when it is run and what it is for. 2) A cleaner solution. Add an overriding rule to the UDEV rules set. These are run at boot time to set up the device files in /dev. Add the following file to /etc/udev/rules.d and make sure it is owned by root.root and has "rw-r--r--" permissions. Here's the file: =========== /etc/udev/rules.d/51-local.rules ========================== # # Locally defined rules. # # # Give world read/write access to ttyS* and ttyUSB* serial devices # KERNEL=="tty[A-Z]*", GROUP="uucp", MODE="0666" ======================================================================= You may need to change the file name, which must not overwrite or modify an existing file and MUST follow the file containing a rule that sets the serial ports mode to "0660". Run grep 'KERNEL=="tty[A-Z]*"' /etc/udev/rules.d/* to check which file that is. In my system its in /etc/udev/rules.d/50-udev-default.rules but other distros may differ. Your new file must start with a number that's higher than that of the file containing the default rule. Martin
