105.1 Customize and Use the Shell Environment

Question 1

Describe the Interactive Login Shell

Answer 1

1. Created when you log into a console

2. Created when logged in remotely via SSH

Question 2

Describe the interactive Non-Login Shell

Answer 2

Created when a terminal application such as GNOME Terminal is started

Question 3

/etc/profile

Answer 3

The first file read on a login session. Sets up system-wide environment variables, unmask values, Bash history controls, etc.

Question 4

/etc/profile.d/

Answer 4

The directory that contains extra script configuration files for Bash. The /etc/profile file will read in the contents of this directory

Question 5

/etc/bashrc

Answer 5

You can configure system-wide functions and aliases here

Question 6

/etc/skel

Answer 6

The directory that contains the default .bash_profile, .bashrc, and other files that are added to a users home directory when an account is created on the system.

Question 7

~/.bash_profile

Answer 7

This file can contain a users modified PATH environment variable and will source the ~/.bashrc file.This file can also be named ~/.profile on some distributions.

Question 8

~/.bashrc

Answer 8

Local user command aliases and functions are defined here. This file sources the /etc/bashrc file.

Question 9

~/.bash_logout

Answer 9

This file gets called on a user logout and can be used to shut down applications, display a message, or to perform other environment cleanup tasks.

Question 10

~/.bash_login

Answer 10

This file gets called on a user login. Typically,.bash_profile and .bashrc are used instead of this file

Question 11

What does the command env do

Answer 11

Command used to view environment variables for the current shell

Question 12

What doe the command export do

Answer 12

Command used to allow child shell sessions to use an environment variable

Question 13

What does the set command do

Answer 13

By itself, displays all Bash shell settings, variables and functions. Can also be sued to enable and disable Bash settings

Question 14

What does the unset command do

Answer 14

Used to remove an environment variable and its value

Question 15

What does the alias command do

Answer 15

used to create a shortcut to a longer command, typically with options

Question 16

What does the function command do

Answer 16

A bash keyword is used to indicate that a new Bash function follows. A Bash function is any custom command that a user can use in a Bash shell.

Question 17

what do the . (dot) command do

Answer 17

Used to source or apply functions from a file into the current Bash session or a shell script

Question 18

What does the command source do

Answer 18

The same as the . (dot) command where it is sed to source or apply functions from a file into the current Bash session or a shell script