On 5/8/21 6:33 AM, Carlos E. R. wrote:
On 08/05/2021 08.43, -pj wrote:
Hi, I installed K3b on my 32 bit and 64 bit (TDE) computers and decided to test how the application performed.
Settings > Configure K3b > Devices > Displays the following error:
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Optical Devices
In order to give K3b full access to the writer device the current user needs be added to a group cdrom.
The Permission helper that could do this for you was not enabled during build.
Please rebuild the package with the Permission helper enabled or contact your distribution.
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K3b was able on both machines (32 and 64 bit TDE) to complete the burning of an .iso and verify without incident.
So, despite the error message (below), you were able to burn an iso? Then ignore the error message, it is just ancient and not real anymore.
I attached a screenshot of the error message here. > https://susepaste.org/26598876
1. How can I enable this permission helper that is spoke of?
No idea what that is. Anyway, you can't.
2. How should I go about adding a cdrom group? I am not seeing the capability in (YaST > Control Center > Security and Users > User and Group Management >) most likely I am missing something about how to use this particular module.
See the other reply. But you do not need that.
3. Do I need to uninstall K3b and reinstall again (once a group cdrom is added)?
No. Just log out, log in.
4. Will removing K3b and the dependencies of K3b through YaST Software Manager create potential dependency problems?
5. I was looking at this YaST CD-ROM Drives module page: > https://en.opensuse.org/YaST_CD-ROM_Drives
Most likely I am missing something in the YaST - User and Group Management section. Is there a preferred openSUSE Wiki Portal on this topic of adding groups and users through YaST?
I looked at this information briefly and it refers to a CD-ROM Drives module: > https://en.opensuse.org/YaST_CD-ROM_Drives < Seems to be not relevant most likely.
What are your thoughts on this matter?
The permissions for you to handle the cdrom were done via adding you to the cdrom group, years ago. But the current system doesn't need that; instead, the user "on the seat" gets the permission automatically.
cer@Telcontar:~> l /dev/cdrom lrwxrwxrwx 1 root root 3 May 4 19:49 /dev/cdrom -> sr0 cer@Telcontar:~> l /dev/sr0 brw-rw----+ 1 root cdrom 11, 0 May 4 19:49 /dev/sr0 cer@Telcontar:~>
Do you see the "+" in the permissions of the actual device? That indicates that there are more permissions as ACLS. So you have to do this to see them:
cer@Telcontar:~> getfacl /dev/sr0 getfacl: Removing leading '/' from absolute path names # file: dev/sr0 # owner: root # group: cdrom user::rw- user:cer:rw- group::rw- mask::rw- other::---
cer@Telcontar:~>
(see "man acl")
And you can see that user "cer" has "rw" permissions.
Great explanation on this. I can see this now and understand the link from: /dev/cdrom ->sr0 -to- /dev/sr0 -to- getfacl /dev/sr0 ACLS is something new to me most certainly. Noting the "+" in the permissions of the actual device makes alot more sense seeing the "getfacl" commands output. I see there is a man page for the getfacl command also. This answers my question as to why the K3b application worked..well with displaying the error listed above. The actual device is /dev/sr0 and user:username:rw- does have read and write permissions. Basically the entire output of getfacl /dev/sr0 comes together with #group: cdrom since /dev/cdrom -> has rwxrwxrwx permissions (any user can rwx). 1. Can I ask about the following possibly?: Prefixes in the /dev directory have l,c and b (which is the prefix for /dev/sr0). Is there a fairly quick explanation for these by chance. The excellent answers to my question here has really helped me to understand more that a software message does not necessarily mean that it knows exactly what it is trying to convey. I really appreciate the input. 2. I notice that /dev/cdrw -> sr0 is not listed in getfacl /dev/sr0 output though.
How is it done? Well, the "display manager" does that job when you login.
"In simple terms, a display manager is a program that provides graphical login capabilities for your Linux distribution. It controls the user sessions and manages user authentication. Display manager starts the display server and loads the desktop environment right after you enter your username and password.Dec 4, 2020"
<https://itsfoss.com/display-manager/>
gdm, wdm, kdm, sddm...
Thanks for adding this portion on display managers also.
The same technique is used to grant you permissions to use devices connected on the USB.
I think that "polkit" is also part of the system, but that's an area that I know little about. See "man polkit" perhaps.
Noted. I feel more comfortable now able to look over the warning displayed in K3b. The tip on polkit is interesting also. -Regards :|