Module 7

Question 1

What is Git?

• Another name for Gigabit
• Version control software
• Configuration management software
• Open source malware

Answer 1

• Version control software

Question 2

Which numeric variable test expressions work? (Select two)

• (($A == $B))
• ((! $A -eq $D))
• (($A != $C))
• ((! $A = $D))

Answer 2

• (($A == $B))

- (($A != $C))

Question 3

What does export a variable mean?

• Allow the variable to become accessible by child processes
• Allow the variable to become accessible by parent process
• Send the variable to a file
• Send the variable to foreign countries

Answer 3

• Allow the variable to become accessible by child processes

Question 4

Which command will display the following information?

The number of different shells being used on a Linux system

• $ cat /etc/passwd | cut -d: -f7 | uniq | sort | wc -l
• $ cat /etc/passwd | cut -d: -f7 | wc -l | sort | uniq
• $ cat /etc/passwd | cut -d: -f7 | sort | wc -l | uniq
• $ cat /etc/passwd | cut -d: -f7 | sort | uniq | wc -l

Answer 4

• $ cat /etc/passwd | cut -d: -f7 | sort | uniq | wc -l

Question 5

! /bin/bash

What will be displayed? Assume the script has the execution bit set.

$ cat myscript.sh

echo “$0 $@ $1 $2”
$ ./myscript.sh Hello World!

• Nothing
• Hello World!
• ./myscript.sh Hello World!
• ./myscript.sh Hello World! Hello World!

Answer 5

• ./myscript.sh Hello World! Hello World!

Question 6

Which outputs are a result of the following command? (Choose all that apply) Assume each original name started with a capitalized letter followed by lower-case letters.

$ tr [h-z][H-Z] < names

• DONaLd DUcK
• MIcKeY MOUSe
• WaLT DiSNey
• WiNNie THe POOH

Answer 6

• DONaLd DUcK

- MIcKeY MOUSe

Question 7

What will be displayed? Assume the script has the execution bit set.

$ cat myscript.sh

#! /bin/bash
function print_positional_params () {
echo "$3 $1 $2"
}
print_positional_params "$3" "$2" "$1"
#./myscript.sh one two three

• one two three
• one three two
• two three two
• three one two

Answer 7

• one three two

Question 8

Find the match.

[ A = B ]
[ A -eq B ]
[ -d A ]
[ -f A ]

Strings A is equal to String B
A is numerically equal to B
A is a directory that exists
A is a file that exists

Answer 8

[ A = B ] Strings A is equal to String B

[ A -eq B ] A is numerically equal to B

[ -d A ] A is a directory that exists

[ -f A ] A is a file that exists

Question 9

Which command will display the following information?

The number of users who use BASH shell

• $ cat /etc/passwd | cut -d: -f7 | sort | grep bash
• $ cat /etc/passwd | cut -d: -f7 | sort | wc -l
• $ cat /etc/passwd | cut -d: -f7 | wc -l | grep bash
• $ cat /etc/passwd | cut -d: -f7 | grep bash | wc -l

Answer 9

• $ cat /etc/passwd | cut -d: -f7 | grep bash | wc -l

Question 10

How do you run a shell script? (Select three)

Assume the file has the execute bit set . PATH is not set to the current directory.

• myscript.sh
• ./myscript.sh
• . ./myscript.sh
• source ./myscript.sh

Answer 10

• ./myscript.sh
• . ./myscript.sh
• source ./myscript.sh

Question 11

Before a user-defined variable can be used by processes that run in subshells, that variable must be __________.

• imported
• Falsevalidated by running the env command
• exported
• redirected to the BASH shell

Answer 11

• exported

Question 12

Which of the following will display the message welcome home if the cd /home/user1 command is successfully executed?

• cd /home/user1 && echo “welcome home”
• cat “welcome home” || cd /home/user1
• cd /home/user1 || cat “welcome home”
• echo “welcome home” && cd /home/user1

Answer 12

• cd /home/user1 && echo “welcome home”

Question 13

How do you indicate a comment line in a shell script?

• There are no comment lines in a shell script.
• Begin the line with #!.
• Begin the line with !.
• Begin the line with #.

Answer 13

• Begin the line with #.

Question 14

Consider the following shell script:
echo -e “What is your favorite color?--> \c”
read REPLY
if [ $REPLY = “red” -o $REPLY = “blue” ]
then
echo “The answer is red or blue.”
else
echo “The answer is not red nor blue.”
fi

What would be displayed if a user executes this shell script and answers Blue when prompted?

• The answer is red or blue.
• The answer is not red nor blue.
• The code would cause an error.
• The answer is red or blue. The answer is not red nor blue.

Answer 14

• The answer is not red nor blue.

Question 15

The sed and awk commands are filter commands commonly used to format data within a pipe. True or False?

True

False

Answer 15

• True

Question 16

Which of the following variables could access the value “/etc” within the sample shell script, if the sample shell script was executed using the bash sample /var /etc /bin command?

• $0
• $1
• $2
• $3

Answer 16

• $2

Question 17

Both aliases and functions can be used to store commands that can be executed, but functions can also accept positional parameters. True or False?

True
False

Answer 17

• True

Question 18

What would be the effect of using the alias command to make an alias for the date command named cat in honor of your favorite pet?

• It cannot be done as there already is an environment variable cat associated with the cat command.
• It cannot be done because there already is a command cat on the system.
• When you use the cat command at the command prompt with the intention of viewing a text file, the date appears instead.
• There is no effect until the alias is imported because it is a user-declared variable.

Answer 18

• When you use the cat command at the command prompt with the intention of viewing a text file, the date appears instead.

Question 19

Which of the following lines can be used to perform command substitution within a shell script? (Choose all that apply.)

• command
• ${command}
• ${!command}
• $(command)

Answer 19

• command

- $(command)

Question 20

Which of the following operators reverses the meaning of a test statement?

• # !
• -o
• -a
• !

Answer 20

• !