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-----BEGIN PGP SIGNED MESSAGE----- Hash: SHA256 On 2016-12-08 13:55, Dave Howorth wrote:
I'm trying to run an app in chromium to talk to an external device connected by serial over USB, as /dev/ttyUSB. And I'm failing.
I'm handicapped by knowing nothing about chromium and not much about ttys and groups in the modern world.
The app says it is trying to contact /dev/ttyUSB0 and then it says it is 'Not Found'.
I'm wondering if there is a permissions, or other security, issue?
Does chromium prevent apps trying to talk to external devices by default? (and if not why not?!)
No, it is not chromium, it is the system administrator, Mr Root. Or in this case, openSUSE install defaults.
If I look at the device: $ ls -l /dev/ttyUSB0 crw-rw---- 1 root dialout 188, 0 Dec 8 11:37 /dev/ttyUSB0
it seems like nothing should be able to talk to it unless they are either root or a member of the dialout group.
That is so.
I added my self to the dialout group using gpasswd. Some online stuff indicates I need to logout and then back in before it will take effect. That seems a fairly draconian thing to have to doo just to use a new group membership. Is there another way?
To my knowledge, no, the newgrp command Andrei mentioned is new to me.
I suppose I could change the group that the tty belongs to, but that seems like too big a bodge.
Not really. All those files are dynamic, created on boot, and on device connect. So a reboot would solve a disaster in there ;-) It is possible that disconnecting and connecting the serial port emulator hardware would recreate the device. - -- Cheers / Saludos, Carlos E. R. (from 13.1 x86_64 "Bottle" (Minas Tirith)) -----BEGIN PGP SIGNATURE----- Version: GnuPG v2.0.22 (GNU/Linux) iF4EAREIAAYFAlhKBaIACgkQja8UbcUWM1w0ngD/XleZ4jhkSLSE88FKqi8OGUYN qWNRhT2xWs11M7M42scA/Rz/hg5/bLjy0MjcF/+iG/kgJ9iZlAhWhP137XYo6+9g =tWj3 -----END PGP SIGNATURE----- -- To unsubscribe, e-mail: opensuse+unsubscribe@opensuse.org To contact the owner, e-mail: opensuse+owner@opensuse.org