OSA A3

Q 3A: To study adding of users and also access rights.

->   Program:

while true

do

echo "1.Create group:";

echo "2.Create users:";

echo "3.Delete users:";

echo "4.Delete group"

echo "5.Display users and groups in the system"

echo "6.Exit";

echo "Enter your choice : ";

read ch;

case $ch in

1)

echo "Enter the group name  :"

read gname

groupadd $gname

system-config-users

;;                                              # to break first switch case

2)

echo "Enter the user name :";

read username

echo "Enter the group name :";

read gname

useradd $username -g $gname

system-config-users

;;

3)

echo "delete the user"

echo "enter the name of the user "

read username

userdel $username

system-config-users

;;

4)

echo "delete group"

echo "enter name of  a group "

read gname

groupdel $gname

system-config-users

;;

5)

echo "Dispaly users and groups from the system:"

system-config-users

;;

6)

exit;

;;

esac                                         # end of switch case

done

OUTPUT:-

[student@localhost ~]$ cd Documents/Assignments

[student@localhost Assignments]$ ls

A-1f.sh   A-2.sh   A-4.sh    Assign14B.zip     CpuInfo.java  file_name2

A-1f.sh~  A-2.sh~  A-5.sh    Assign2final.zip  debug.py      test1

A-1.sh    A-3.sh   A-6.sh    Assign6B.zip      debug.py~

A-1.sh~   A-3.sh~  Assign14  CpuInfo.class     file_name1

[student@localhost Assignments]$ ./A-3.sh

1.Create group:

2.Create users:

3.Delete users:

4.Delete group

5.Display users and groups in the system

6.Exit

Enter your choice :

1

Enter the group name  :

abc

./A-3.sh: line 20: /usr/sbin/groupadd: Permission denied

Error executing command as another user: Request dismissed

/*Group and user addition are functions which can only be carried on by the root user! Hence a normal user cannot create or delete users or groups. So we switch to the root user using the 'su' command! */

1.Create group:

2.Create users:

3.Delete users:

4.Delete group

5.Display users and groups in the system

6.Exit

Enter your choice :

6

[student@localhost Assignments]$ su

Password:

[root@localhost Assignments]# ./A-3.sh

1.Create group:

2.Create users:

3.Delete users:

4.Delete group

5.Display users and groups in the system

6.Exit

Enter your choice :

1

Enter the group name  :

clubs

[root@localhost Assignments]# ./A-3.sh

.Create group:

2.Create users:

3.Delete users:

4.Delete group

5.Display users and groups in the system

6.Exit

Enter your choice :

2

Enter the user name :

barcelona

Enter the group name :

clubs

1.Create group:

2.Create users:

3.Delete users:

4.Delete group

5.Display users and groups in the system

6.Exit

Enter your choice :

2

Enter the user name :

manchesterunited                               

Enter the group name :

clubs

1.Create group:

2.Create users:

3.Delete users:

4.Delete group

5.Display users and groups in the system

6.Exit

Enter your choice :

2

Enter the user name :

realmadrid

Enter the group name :

clubs

[root@localhost Assignments]# ./A-3.sh

1.Create group:

2.Create users:

3.Delete users:

4.Delete group

5.Display users and groups in the system

6.Exit

Enter your choice :

3

delete the user

enter the name of the user

test

userdel: user 'test' does not exist

1.Create group:

2.Create users:

3.Delete users:

4.Delete group

5.Display users and groups in the system

6.Exit

Enter your choice :

3

delete the user

enter the name of the user

manchesterunited

[root@localhost Assignments]# ./A-3.sh

1.Create group:

2.Create users:

3.Delete users:

4.Delete group

5.Display users and groups in the system

6.Exit

Enter your choice :

4

delete group

enter name of  a group

clubs

groupdel: cannot remove the primary group of user 'barcelona'

/*Clubs is the primary group of  Barcelona. We cannot delete a primary group of  any user!
Therefore, we couldn't delete group 'clubs' */

[root@localhost Assignments]# ./A-3.sh

1.Create group:

2.Create users:

3.Delete users:

4.Delete group

5.Display users and groups in the system

6.Exit

Enter your choice :

1

Enter the group name  :

clubs2

/* Here we created a new group and added Barcelona to it! Now let's try deleting clubs 2! */

1.Create group:

2.Create users:

3.Delete users:

4.Delete group

5.Display users and groups in the system

6.Exit

Enter your choice :

4

delete group

enter name of  a group

clubs2

/* Yes! We could succesfully delete 'clubs2' as it is not a primary group of any user. */

[root@localhost Assignments]# ./A-3.sh

1.Create group:

2.Create users:

3.Delete users:

4.Delete group

5.Display users and groups in the system

6.Exit

Enter your choice :

5

Dispaly users and groups from the system: