Monitoring of Work
The groupadd Command is used to create a new working group and the groupdel command is used to delete an existing working group.The gpasswd command is used to add or remove a user to a particular working group.
- "gpasswd -a
" adds user to the group - "gpasswd -d
" removes user from the group
It is possible for the user to use the id and groups programs to query the active user and group IDs.
The newgrp program must be used to change the active group.
- id - print real and effective user and group IDs
- groups - print the groups a user is in
- newgrp
- allows the user to change the active group identity to another group that he or she is a member of. - newgrp - allows the user to change the active group identity as his or her main group.
The user is able to monitor the working user and group identity and change the active group membership via the id and newgrp commands.
It was previously stated that the UNIX operating system is a multi-user system. There are several commands in UNIX to monitor other users who are actively using the system at any given time.
who - lists the users working on the system, along with the system entry times.
w - lists the users running on the system and which programs they are running.
whoami - shows you which user ID you are using and when you log in.
In all command outputs, PTSs mean pseudo terminals (virtual terminals). This indicates that the user is not using a cable-connected terminal directly. pts/0 is the first virtual terminal and pts/1 is the second virtual terminal.
Password and shell change
The user changes his/her password with the "passwd" program. If the password is not complicated enough, "passwd" will alert the user. For security reasons, the old password is asked once and the new password is asked twice.The user can change the used shell with the "chsh" program. The list of existing shells is also written in the file "/etc/shells". With "chsh", only the shells written in this file are allowed to be used. User is asked for password for security reasons before shell change.
To read my previous article: User Concept and User Groups
