How do I give myself permission to use my modem in my machine? I am trying to use efax-cgt to send faxes and don't have permission to use the modem.
How can that be?
ted@ted-desktop:~$ id uid=1000(ted) gid=1000(ted) groups=1000(ted),4(adm),24(cdrom),27(sudo),30(dip),46(plugdev),108(lpadmin),124(sambashare) ted@ted-desktop:~$
Your modem device is probably registered as a TTY or ACM device. These can be found in /dev like this:
$ ls -l /dev/ttyS*
crw-rw---- 1 root dialout 4, 64 Nov 3 09:37 /dev/ttyS0
[...]
Notice the permissions set to root and the dialout group for the example listed. To be able to read/write to the device as a regular user, just make sure you're a member of this group. Several options to do this exist: through the user management in system settings or command line like this:
sudo adduser username dialout
Then log out of your Ubuntu session and log back in (or simply reboot) to make this change effective.
In case of trouble, check with id whether you're indeed a member and verify with ls -l on the device what permissions you need. In the unlikely case your modem driver doesn't use the regular ACM/serial driver interfacing, edit your question to include these details (we don't have this specific modem).
idrun from a terminal by [edit]ing your question. This should show to what groups you are a member of. – gertvdijk Nov 03 '14 at 12:58