Chapter 3 (Using the Shell)

Question 1

A — is like a program or a macro

Answer 1

Script

Question 2

A — is essentially a list of commands stored in a text file.

Answer 2

Script

Question 3

The default shell for all Linux systems is —

Answer 3

Bash

Question 4

Changing to a new default shell is very easy using the — command.

Answer 4

usermod

Question 5

The – — records each command that you enter at the shell prompt.

Answer 5

Command History

Question 6

The — command displays the entire history list, which normally includes at least — commands

Answer 6

History, 1000

Question 7

A exclamation point is sometimes called a – in unix and Linux

Answer 7

bang

Question 8

The — script contains configuration information that applies to every user on the system.

Answer 8

/etc/profile

Question 9

Each users home directory can contain another start-up script called—

Answer 9

.profile

Question 10

The — script is executed each time the user starts a bash shell.

Answer 10

.bashrc

Question 11

(Bash Scripts)

— is executed each time a bash shell is started.

Answer 11

.bash_default

.bash_login

Question 12

(Bash Scripts)

— is executed each time a user closes a bash shell

Answer 12

.bash_logout

Question 13

A — is a string of characters that is substituted for another string of characters at the shell prompt.

Answer 13

Alias

Question 14

The — command lets you define how the shell will substitute one string of text for another string of text that you enter at a shell prompt.

Answer 14

Alias

Question 15

(Alias example)

Answer 15

alias muont=mount

Question 16

The — command writes text to the screen.

Answer 16

Echo

Question 17

As used in a Linux shell, is a name that can have a value assigned to it.

Answer 17

Shell variable

Question 18

(Note)

Variables are typically created using all uppercase letters, though they don’t have to be. `

Answer 18

|

Question 19

You can use the — command to start a program with an environment variable setting that is not part of your current environment.

Answer 19

env

Question 20

An — — is a variable that has typically been defined (assigned a value) as part of the process of initializing either the operating system or the particular shell in which a user is working.

Answer 20

Environment Variable

Question 21

The — command displays a list of all environment variables defined in your current environment.

Answer 21

set

Example $ set

Question 22

Channels of communication in Linux can be redirected, however, using — operators

Answer 22

Redirection

Question 23

When a program expects input such as a line of text, it reads that information from the standard — – – channel.

Answer 23

Standard Input channel (abbreviated STDIN)

Question 24

When a program generates output, it normally sends it to the — — —

Answer 24

Standard output channel (abbreviated STDOUT)

Question 25

A special tool for redirecting communication between programs is called a —

Answer 25

pipe

Question 26

A — connects the output channel of one command to the input channel of another command.

Answer 26

pipe

Question 27

$ ls /etc | sort

Answer 27

The result is that sort writes to the screen the lines from ls, sorted according to the first word in each line.

Question 28

The — command is used to display the number of characters words and lines in a text file.

Answer 28

wc

Question 29

> filename

Answer 29

Writes STDOUT output to the given file name.

(Example) ls -l > savelisting

Question 30

> > filename

Answer 30

Appends to STDOUT output to the given file name (adding it to the end of any existing file contents)
(Example) can newfile&raquo_space; existing_file

Question 31

<filename

Answer 31

Sends data from the given file name as the STDIN, rather than reading from the keyboard.
(Example) my_script<input_codes

Question 32

You can use the — command to write the contents of any file to the screen.

Answer 32

cat

Question 33

(Note) Using the append operator, you can add the small file to the end of the larger file.

Answer 33

(Example)

$ cat small_file&raquo_space; large_file

Question 34

The — command lets you redirect output to a file and also to the screen.

Answer 34

tee

Question 35

$ sort data_file | tee sorted_data

Answer 35

The following command displays the output of the sort command and also writes it to the file sorted_data

Question 36

$ sort data_file | tee -a sorted_data

Answer 36

You can have the tee command append data to the end of the named file by adding an -a option.