PowerShell on Linux - Interactive Code Practice

Practice - 5 Tasks

1fill in blank

easy

Complete the code to display the current directory in PowerShell on Linux.

PowerShell

Get-Location | Select-Object -ExpandProperty [1]

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

APath

BName

CLength

DMode

Attempts:

3 left

💡 Hint

Common Mistakes

Choosing 'Name' which only shows the folder name, not full path.

Using 'Length' or 'Mode' which are unrelated properties.

The Path property shows the full current directory path in PowerShell.

2fill in blank

medium

Complete the code to list all files in the current directory on Linux using PowerShell.

PowerShell

Get-ChildItem -File | Where-Object [1] { $_.Length -gt 0 }

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

A-Property

B-FilterScript

C-Filter

Attempts:

3 left

💡 Hint

Common Mistakes

Using '-Filter' which is a parameter for Get-ChildItem, not Where-Object.

Using '-Property' which is not valid for Where-Object.

The -FilterScript parameter is used with Where-Object to filter files by a script block.

3fill in blank

hard

Fix the error in the code to create a new directory named 'TestDir' on Linux using PowerShell.

PowerShell

New-Item -ItemType Directory -Name [1]

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

A'TestDir'

B-TestDir

CTestDir

D/TestDir

Attempts:

3 left

💡 Hint

Common Mistakes

Including quotes around the directory name.

Using a path starting with '/' which is not needed here.

On Linux PowerShell, the -Name parameter expects the directory name without quotes.

4fill in blank

hard

Fill both blanks to read the content of a file named 'log.txt' and display only lines containing 'error'.

PowerShell

Get-Content [1] | Where-Object { $_ [2] 'error' }

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

Alog.txt

B-like

C-match

Dlog

Attempts:

3 left

💡 Hint

Common Mistakes

Using '-like' which is for wildcard matching, not regex.

Using 'log' instead of the full file name.

Get-Content reads the file 'log.txt'. The -match operator filters lines containing 'error'.

5fill in blank

hard

Fill all three blanks to create a hashtable with file names as keys and their sizes as values for files larger than 1KB.

PowerShell

$files = Get-ChildItem -File | Where-Object { $_.Length [1] 1024 }
$sizes = @{}
foreach ($file in $files) { $sizes[[2]] = [3] }

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

A>

B$file.Name

C$file.Length

D<

Attempts:

3 left

💡 Hint

Common Mistakes

Using '<' instead of '>' causing wrong files to be selected.

Swapping keys and values in the hashtable.

The code filters files larger than 1024 bytes using >. The hashtable uses file.Name as keys and file.Length as values.

Practice

1. What command do you use to start PowerShell on a Linux system?

easy

A. pwsh

B. powershell.exe

C. start-ps

D. shellps

Solution

1. Step 1: Recall the PowerShell start command on Linux

   On Linux, PowerShell is started by typing pwsh in the terminal.

2. Step 2: Compare options with the known command

   powershell.exe, start-ps, and shellps are not valid commands to start PowerShell on Linux.

3. Final Answer:

   pwsh -> Option A

4. Quick Check:

   PowerShell start command on Linux = pwsh [OK]

Hint: Remember: 'pwsh' starts PowerShell on Linux terminals [OK]

Common Mistakes:

• Typing 'powershell.exe' which is for Windows only
• Using 'start-ps' which is not a valid command
• Confusing shell names

2. Which of the following is the correct syntax to run a Linux command inside PowerShell on Linux?

easy

A. Run-Command 'ls -l'

B. Invoke-Linux ls -l

C. ls -l

D. Start-Linux ls -l

Solution

1. Step 1: Understand how Linux commands run in PowerShell on Linux

   PowerShell on Linux allows running Linux commands directly by typing them as is, like ls -l.

2. Step 2: Evaluate each option

   Invoke-Linux ls -l, Run-Command 'ls -l', and Start-Linux ls -l are not valid syntax to run Linux commands.

3. Final Answer:

   ls -l -> Option C

4. Quick Check:

   Run Linux commands directly in PowerShell = ls -l [OK]

Hint: Run Linux commands directly without extra syntax in PowerShell [OK]

Common Mistakes:

• Adding unnecessary PowerShell cmdlets before Linux commands
• Using quotes incorrectly around Linux commands
• Assuming Linux commands need special wrappers

3. What will be the output of this PowerShell on Linux command sequence?

pwsh
$files = ls /etc | Where-Object { $_.Name -like '*.conf' }
$files.Count

medium

A. Always zero because filtering is incorrect

B. An error because ls is not recognized

C. The list of all files in /etc

D. The number of files in /etc ending with .conf

Solution

1. Step 1: Understand the command sequence

   The command ls /etc lists files in /etc. The Where-Object filters files whose names end with '.conf'.

2. Step 2: Determine the output of $files.Count

   $files stores the filtered list, so $files.Count returns the number of such files.

3. Final Answer:

   The number of files in /etc ending with .conf -> Option D

4. Quick Check:

   Count filtered files = number [OK]

Hint: Count filtered files with .Count property after Where-Object [OK]

Common Mistakes:

• Thinking ls is not recognized in PowerShell on Linux
• Assuming filtering syntax is invalid
• Confusing output with file list instead of count

4. You run this script in PowerShell on Linux:

pwsh
$process = Get-Process -Name "bash"
Write-Output $process.Id

But it returns an error: "Get-Process: The term 'Get-Process' is not recognized." What is the likely cause?

medium

A. PowerShell is not installed correctly on Linux

B. You are running the script in the Linux shell, not inside PowerShell

C. The process 'bash' does not exist

D. Get-Process cmdlet is not available on Linux PowerShell

Solution

1. Step 1: Analyze the error message

   The error says 'Get-Process' is not recognized, which usually means the command is run outside PowerShell.

2. Step 2: Understand environment context

   If you run PowerShell commands in the Linux shell (bash), they won't work. You must be inside PowerShell (started with pwsh) to run Get-Process.

3. Final Answer:

   You are running the script in the Linux shell, not inside PowerShell -> Option B

4. Quick Check:

   Run PowerShell cmdlets inside pwsh shell [OK]

Hint: Run PowerShell commands only inside pwsh shell, not bash [OK]

Common Mistakes:

• Assuming Get-Process is missing on Linux PowerShell
• Thinking the process 'bash' does not exist
• Not starting PowerShell before running commands

5. You want to write a PowerShell script on Linux that lists all running processes and filters only those owned by the current user. Which approach is correct?

hard

A. Get-Process | Where-Object { $_.UserName -eq $env:USER }

B. ps -u $USER | pwsh

C. Get-Process | Where-Object { $_.UserName -eq (whoami) }

D. Get-Process | Where-Object { $_.UserName -eq $env:USERNAME }

Solution

1. Step 1: Identify environment variable for current user in PowerShell on Linux

   PowerShell on Linux uses $env:USER to get the current user's name.

2. Step 2: Check filtering syntax for processes

   Filtering processes by Where-Object { $_.UserName -eq $env:USER } correctly compares the process owner to the current user.

3. Step 3: Evaluate other options

   ps -u $USER | pwsh mixes Linux command with PowerShell incorrectly. Get-Process | Where-Object { $_.UserName -eq (whoami) } uses command output that may not match precisely. Get-Process | Where-Object { $_.UserName -eq $env:USERNAME } uses $env:USERNAME which is typically not set on Linux.

4. Final Answer:

   Get-Process | Where-Object { $_.UserName -eq $env:USER } -> Option A

5. Quick Check:

   Use $env:USER for current user in PowerShell on Linux [OK]

Hint: Use $env:USER to get current user in PowerShell on Linux [OK]

Common Mistakes:

• Using $env:USERNAME which isn't set on Linux PowerShell
• Mixing Linux commands like 'ps -u $USER' with PowerShell incorrectly
• Using command output like (whoami) without precise matching