I am using an app called efax-gtk and it needs to access my modem. I am getting permission errors
efax-0.9a: 12:57:53 Error: can't open serial port /dev/ttyACM0: Permission denied
And the dev tells me:
“find out what group it belongs to with
ls -l /dev/ttyACM0 and add yourself to the group.”
How to do that? I see my user name, “shmuel”, in the output, but I still get the error.
ls -l /dev/ttyACM0
crw------- 1 uucp shmuel 166, 0 Aug 11 12:52 /dev/ttyACM0
I added shmuel to uucp
sudo gpasswd -a shmuel uucp
[sudo] password for shmuel:
Adding user shmuel to group uucp
but I still get the error.
Does it require reboot?
(I’m in the middle of video editing…)
nice … a modem? i would like to be able to use such device fot fax… but ISP here do not provide real telefon lines
From the wiki page you just read:
post the output:
Reboot, but log out log in should do guess.
edit: @jonathon beat me to it
Good, so I added myself to the group, but by default the group has no access rights to this file. I can change the rights manually to read and write, but it doesn’t survive a reboot.
What are the default permissions?
The default permissions are as in screenshot. I change them by opening the directory in root Thunar, right-click, then permissions tab.
Hmm. You might need to tweak the udev rule for the modem so it adds
MODE="0660" for group read-write permissions, https://wiki.archlinux.org/title/Udev.
sudo chmod ug=rw /dev/ttyACM0 do it?
Perhaps that is what you said?
It would fix it for the current session, but will reset when you reboot. So kind of.
In contrast, a udev rule will trigger whenever the hardware is connected, so will “fix” it forever.
I see. I shall be studying the link you posted. Thanks!
Thanks to all for the wise comments. I am finding that Efax-gtk is buggy in many ways, so I am not even going to put more effort into it.
I did finally get Hylafax to work, after joining the appropriate group at SourceForge, and the dev sorted out my issues. So I don’t really need efax.