Does this help?
Not so far
Been there a couple of times but I cannot find the info I am looking for unfortunately.
It is relatively easy to manage existing groups it seems ..... really all I need from that is to either make a user a member of a specific group or not, and when a member, the user is granted the privileges of that group.
I have yet to find what the privileges for the predefined system groups are.
The user groups created with each user are a different type of group, and affect access to and permissions of the specific files etc created by the owner. So if user A allowed user B to be a member of the user A group, user B would then have access to user A files, dependent on the specific permissions assigned to those files. (that is how I understand it presently)
But if one looks at the 'standard' groups which are preset in the system, they grant privileges to their members, to do things non-members are not allowed to do.
Somewhere there must be a file or such that specifies what privileges are granted to the members of each group.
Either I am completely missing what I am reading, or I have not read what I need to read .... either way I am still in the dark!
@uncleV ....... at the present state of my understanding I will refrain from commenting on your questions ....... maybe with more information (if I find it) things will be clearer. All I can say is that user groups and system groups are different.http://www.redhat.com/docs/manuals/linux/RHL-7.3-Manual/ref-guide/s1-users-groups-private-groups.html
That might help answer the questions
/etc/password and /etc/groups have some information but not what I am looking for unfortunately.
Onwards and upwards I guess