Read-only variables (readonly) in Bash Scripting - Interactive Code Practice

Practice - 5 Tasks

1fill in blank

easy

Complete the code to declare a read-only variable named MY_VAR with value 10.

Bash Scripting

readonly [1]=10

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

Avar1

Bmy_var

CMY_VAR

Dreadonly

Attempts:

3 left

💡 Hint

Common Mistakes

Using 'readonly' as the variable name.

Using lowercase variable names when uppercase is expected.

The readonly command followed by the variable name MY_VAR makes it read-only.

2fill in blank

medium

Complete the code to print the value of the read-only variable MY_VAR.

Bash Scripting

echo [1]

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

AMY_VAR

B$MY_VAR

CMY_VAR$

D${MY_VAR}

Attempts:

3 left

💡 Hint

Common Mistakes

Forgetting the dollar sign before the variable name.

Using variable name without braces which can cause errors in some contexts.

Use ${MY_VAR} to correctly reference the variable value in bash.

3fill in blank

hard

Fix the error in the code that tries to change a read-only variable MY_VAR to 20.

Bash Scripting

readonly MY_VAR=10
[1]
MY_VAR=20

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

Aunset MY_VAR

Breadonly MY_VAR

Cexport MY_VAR

DMY_VAR

Attempts:

3 left

💡 Hint

Common Mistakes

Trying to assign a new value directly to a readonly variable.

Using 'export' which does not remove readonly status.

You cannot assign a new value to a read-only variable. You must unset it first to remove the read-only attribute.

4fill in blank

hard

Fill both blanks to declare a read-only variable VAR with value 100 and then print it.

Bash Scripting

[1] VAR=100
[2] $VAR

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

Areadonly

Becho

Cprint

Dexport

Attempts:

3 left

💡 Hint

Common Mistakes

Using 'print' instead of 'echo' to display the value.

Using 'export' which does not make the variable read-only.

Use 'readonly' to declare the variable and 'echo' to print its value.

5fill in blank

hard

Fill all three blanks to declare a read-only variable NAME with value 'Alice', print it, and then try to change it (which should fail).

Bash Scripting

[1] NAME="Alice"
[2] $NAME
NAME=[3]

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

Areadonly

Becho

C"Bob"

Dprint

Attempts:

3 left

💡 Hint

Common Mistakes

Using 'print' instead of 'echo' to display the value.

Trying to change the readonly variable without unsetting it first.

Declare NAME as readonly, print it with echo, then attempt to assign a new value "Bob" which will fail.