PowerShell on macOS - Cheat Sheet & Quick Revision

Recall & Review

beginner

What is PowerShell on macOS?

PowerShell on macOS is a cross-platform command-line shell and scripting language that runs on macOS, allowing users to automate tasks and manage systems using PowerShell commands.

beginner

How do you install PowerShell on macOS?

You can install PowerShell on macOS using Homebrew with the command: brew install --cask powershell. After installation, start it by typing pwsh in the Terminal.

beginner

How do you start PowerShell on macOS after installation?

Open the Terminal app and type pwsh, then press Enter. This launches the PowerShell environment on macOS.

intermediate

Can PowerShell scripts written on Windows run on macOS without changes?

Many PowerShell scripts can run on macOS without changes, but scripts that use Windows-specific features or paths may need adjustments to work on macOS.

beginner

What is a simple PowerShell command to list files in the current directory on macOS?

Use Get-ChildItem or its alias ls to list files and folders in the current directory.

Which command installs PowerShell on macOS using Homebrew?

A brew install --cask powershell

B apt-get install powershell

C yum install powershell

D choco install powershell

Homebrew is the package manager for macOS, and the correct command to install PowerShell is brew install --cask powershell.

How do you start PowerShell in macOS Terminal after installation?

A powershell

B pwsh

C ps

D shell

The command to start PowerShell on macOS is pwsh.

Which command lists files in the current directory in PowerShell on macOS?

A dir

B ls

C Get-ChildItem

D Both B and D

Both ls and Get-ChildItem list files in the current directory in PowerShell.

What might cause a PowerShell script to fail when moved from Windows to macOS?

A Using variables

B Using PowerShell cmdlets

C Using Windows-specific paths or commands

D Using comments

Scripts using Windows-specific paths or commands may not work on macOS without changes.

Is PowerShell on macOS open source and cross-platform?

A Yes, it is open source and runs on multiple platforms

B No, it only runs on Windows

C It is open source but only runs on Windows

D It is proprietary and macOS only

PowerShell is open source and designed to run on Windows, macOS, and Linux.

Explain how to install and start PowerShell on macOS.

Think about the package manager on macOS and the command to launch PowerShell.

Describe one challenge when running PowerShell scripts from Windows on macOS and how to address it.

Consider differences in file paths and system commands.

Practice

1. Which command do you use to start PowerShell on macOS after installation?

easy

A. pwsh

B. powershell

C. ps

D. shell

Solution

1. Step 1: Recall the PowerShell command on macOS

   On macOS, PowerShell is started using the pwsh command, not powershell which is used on Windows.

2. Step 2: Identify the correct command

   Among the options, only pwsh is the correct command to launch PowerShell on macOS.

3. Final Answer:

   pwsh -> Option A

4. Quick Check:

   PowerShell on macOS starts with pwsh [OK]

Hint: Remember: macOS uses 'pwsh' to start PowerShell [OK]

Common Mistakes:

• Typing 'powershell' instead of 'pwsh' on macOS
• Using 'ps' which lists processes, not PowerShell
• Assuming 'shell' starts PowerShell

2. Which of the following is the correct syntax to run a PowerShell script named script.ps1 on macOS terminal?

easy

A. ./script.ps1

B. run script.ps1

C. pwsh script.ps1

D. powershell -file script.ps1

Solution

1. Step 1: Understand how to run scripts in PowerShell on macOS

   On macOS, you run PowerShell scripts by calling pwsh followed by the script name.

2. Step 2: Check each option

   ./script.ps1 tries to run the script directly, which may fail without execution permission and PowerShell context. powershell -file script.ps1 uses Windows syntax. run script.ps1 is invalid. pwsh script.ps1 correctly runs the script with PowerShell.

3. Final Answer:

   pwsh script.ps1 -> Option C

4. Quick Check:

   Run scripts with 'pwsh script.ps1' on macOS [OK]

Hint: Use 'pwsh script.ps1' to run scripts on macOS [OK]

Common Mistakes:

• Trying to run script directly without 'pwsh'
• Using Windows PowerShell syntax on macOS
• Using 'run' command which doesn't exist

3. What will be the output of this PowerShell command run on macOS terminal?

pwsh -Command "Write-Output 'Hello macOS'"

medium

A. Hello macOS

B. Write-Output 'Hello macOS'

C. pwsh: command not found

D. Error: Invalid command

Solution

1. Step 1: Understand the command structure

   The command uses pwsh -Command to run a PowerShell command inline, which outputs the string 'Hello macOS'.

2. Step 2: Predict the output

   The Write-Output cmdlet prints the string to the terminal, so the output will be exactly 'Hello macOS'.

3. Final Answer:

   Hello macOS -> Option A

4. Quick Check:

   Write-Output prints text to terminal [OK]

Hint: Write-Output prints text; expect exact string output [OK]

Common Mistakes:

• Confusing command string with output
• Assuming 'pwsh' is not installed
• Expecting error due to quotes

4. You try to run a PowerShell script on macOS with pwsh ./myscript.ps1 but get a permission denied error. What is the most likely fix?

medium

A. Use sudo pwsh ./myscript.ps1 to run as admin

B. Run chmod +x myscript.ps1 to add execute permission

C. Rename the script to myscript.sh

D. Reinstall PowerShell on macOS

Solution

1. Step 1: Identify cause of permission denied

   On macOS, scripts need execute permission to run. Without it, you get a permission denied error.

2. Step 2: Fix permission issue

   Using chmod +x myscript.ps1 adds execute permission, allowing the script to run.

3. Final Answer:

   Run chmod +x myscript.ps1 to add execute permission -> Option B

4. Quick Check:

   Permission denied? Add execute permission with chmod [OK]

Hint: Add execute permission with chmod +x before running script [OK]

Common Mistakes:

• Trying to run script without execute permission
• Renaming script to .sh which doesn't help PowerShell
• Using sudo unnecessarily
• Reinstalling PowerShell instead of fixing permissions

5. You want to automate listing all files in your Documents folder on macOS using PowerShell and save the output to a text file named files.txt. Which command correctly does this?

hard

A. Get-ChildItem ~/Documents > files.txt

B. ls ~/Documents > files.txt

C. pwsh -Command "ls" ~/Documents > files.txt

D. pwsh -Command "Get-ChildItem ~/Documents | Out-File files.txt"

Solution

1. Step 1: Use PowerShell cmdlet to list files

   Get-ChildItem lists files and folders in PowerShell. Using ~/Documents targets the Documents folder.

2. Step 2: Redirect output to a file in PowerShell

   PowerShell uses Out-File to save output to a file. The command runs inside pwsh -Command to execute from macOS terminal.

3. Final Answer:

   pwsh -Command "Get-ChildItem ~/Documents | Out-File files.txt" -> Option D

4. Quick Check:

   Use Get-ChildItem with Out-File inside pwsh [OK]

Hint: Use Get-ChildItem piped to Out-File inside pwsh command [OK]

Common Mistakes:

• Using shell redirection > inside PowerShell command incorrectly
• Using 'ls' which is not a PowerShell cmdlet
• Running PowerShell cmdlets outside pwsh context
• Omitting Out-File to save output