Default values for input in Bash Scripting - Interactive Code Practice

Practice - 5 Tasks

1fill in blank

easy

Complete the code to assign a default value 'guest' to the variable 'user' if no input is given.

Bash Scripting

user=${1:-[1]
echo "User is $user"

Drag options to blanks, or click blank then click option'

A$1

Bdefault

Cguest

Dinput

Attempts:

3 left

💡 Hint

Common Mistakes

Using $1 directly without default value syntax.

Using = instead of :- inside the braces.

The syntax ${1:-guest} assigns 'guest' if $1 is empty or unset.

2fill in blank

medium

Complete the code to assign '8080' as the default port if no argument is provided.

Bash Scripting

port=${1:-[1]
echo "Server will run on port $port"

Drag options to blanks, or click blank then click option'

A8080

B3000

C443

D80

Attempts:

3 left

💡 Hint

Common Mistakes

Forgetting to use the :- syntax for default values.

Using a port number that is not the intended default.

The default port 8080 is assigned if no input is given using ${1:-8080}.

3fill in blank

hard

Fix the error in the code to correctly assign 'default.txt' as the filename if no argument is given.

Bash Scripting

filename=${1[1]"default.txt"}
echo "Using file: $filename"

Drag options to blanks, or click blank then click option'

A:-

B:=

C=

D?

Attempts:

3 left

💡 Hint

Common Mistakes

Using '=' instead of ':-' causes wrong behavior when variable is empty.

Omitting the colon ':' changes the meaning.

The correct syntax for default value is ${var:-default}, so ':-' is needed.

4fill in blank

hard

Fill both blanks to assign 'admin' as default user and 'root' as default group if no inputs are given.

Bash Scripting

user=${1[1]"admin"}
group=${2[2]"root"}
echo "User: $user, Group: $group"

Drag options to blanks, or click blank then click option'

A:-

B:=

C-

D=

Attempts:

3 left

💡 Hint

Common Mistakes

Using '=' or ':=' which do not cover empty values.

Mixing different default value syntaxes for user and group.

Use ':-' to assign default if variable is unset or empty for both user and group.

5fill in blank

hard

Fill all three blanks to create a script that assigns default values: 'localhost' for host, '3306' for port, and 'root' for user if no inputs are given.

Bash Scripting

host=${1[1]"localhost"}
port=${2[2]"3306"}
user=${3[3]"root"}
echo "Connecting to $host on port $port as $user"

Drag options to blanks, or click blank then click option'

A:-

B:=

C-

D=

Attempts:

3 left

💡 Hint

Common Mistakes

Using '=' or ':=' which do not cover empty values.

Using '-' without colon which only covers unset variables.

The ':-' syntax is used for all three variables to assign defaults if unset or empty.