CHAPTER EIGHT

Answer 1

1. Username
2. Password placeholder (x)
3. User ID (UID) number for each user
4. Group ID (GID) primary group
5. Comment
6. Home directory - personal folder
7. Shell -command line environment used

Question 2

Command: su -

Answer 2

Become root user

Question 3

Command: useradd -m name

Answer 3

Create user or home folder

Question 4

Command: usermod -s/bin/bash name

Answer 4

Change shell

Question 5

Command: usermod -u 444 name

Answer 5

Change user id

Question 6

Command: usermod - - comment “tom cat” name

Answer 6

Add comment

Question 7

The skeleton folder

Answer 7

This folder contains default files and folders that are automatically copied into the home directory of any new user when they are created using the useradd -m command.

Question 8

Group

Answer 8

A group is a collection of users who share the same role or purpose. All groups have their info stored in the file/etc/group.

Answer 9

1. Group name
2. X group password
3. GID group id number
4. Stores usernames of the group members

Question 10

Command: usermod -aG cartoon name

Answer 10

Add one user

Question 11

Command: usermod -aG developer name

Answer 11

Add many users to a group

Question 12

Primary groups

Answer 12

Every user in Linux must be a member of a primary group. They are referred to as login groups. by default when a new user is created, a group is also created with the same name as the user.

Question 13

secondary groups

Answer 13

a user may or may not be a member of a secondary group. secondary groups are also sometimes referred to as supplementary groups. think of it as any group that a user is a member of aside from the user’s primary group

Question 14

check ownership

Answer 14

chown is - I filename

Question 15

change ownership and check ownership

Answer 15

chown user filename

Question 16

change just group ownership

Answer 16

chown :group filename

Question 17

premission types

Answer 17

r - read
w - write
x - execute

Question 18

permissions for a file

Answer 18

r - be able to view the contents
w - be able to edit the file contents
x - able to run file if executable

Question 19

Permissions for directory

Answer 19

r - be able to list the directory contents
w - be able to create and remove files in the directory
x - be able to change to the directory

Question 20

Command: chmod o+w filename

Answer 20

add write for others

Question 21

Command: chmod a+x filename

Answer 21

add execute for everyone

Question 22

command: chmod g=r filename

Answer 22

set read-only for group

Question 23

command: chmod ug=rwx filename

Answer 23

Give full r,w,x control

Question 24

Command: chmod a= filename

Answer 24

remove all permissions

Question 25

octal Notion

Answer 25

instead of the letters r, w and x you can used the numbers 4,2 and 1 to set file permissions

Question 26

three different streams of data

Answer 26

1. standard input =stdin 2. standard output = stdout 3. standard error = stderr

Question 27

file descriptor

Answer 27

is a number that uniquely identifies an open file in a computer's operating system.