On Mon, 2010-06-07 at 11:28 -0700, David Anderson wrote: > Ubuntu creates /dev/ttyUSB0 for me when > I plug in the usb-to-serial-adapter. I have a > symbolic-link to /dev/ttyUSB0 from 'dosdevices/com1'. > What is new in 10.04 Ubuntu is that I have to sudo chmod o+r > and sudo chmod o+w on /dev/ttyUSB0 every time before I > start the app which uses that serial line. > ttyUSB0 goes away when > I unplug the serial adapter from the USB port or > shut down the laptop (with Ubuntu 10.04)! > This is expected behaviour with a modern kernel using UDEV rules to configure USB devices and set their access permissions. You can change this by (carefully!) altering the rules in /etc/udev/rules.d so the access permissions for /dev/ttyUSB* devices are set to 0666 (all users have read and write access). I can't be more specific because the UDEV rules are one place where Linux distros differ. Ask for help on the appropriate Ubuntu forum and remember to keep copies of your modified rules in a safe place because they can be overwritten in /etc/udev/rules.d by an upgrade or reinstall. Martin
