Contents



Pre-Requisite Knowledge

  • Typing skills
  • Text editing skills
  • Basic Windows Navigation skills
  • Basic screen reading skills
  • Basic knowledge of what a computer operating system is and its features (ie file/folders/applications/shortcuts/file extenstions/etc.)
  • Basic knowledge of computer hardware (hard drive/usb and other peripheral ports/cloud vs local storage)
  • Basic understanding of variables and parameters
  • Basic internet navigation skills and (URL structure)
  • Getting started Lesson for Power Shell


Lesson Overview

Now that you under stand some basic navigational concepts in the powershell we will now cover the basics of data manipulation using powershell commands, namely making folders, moving files and folders, renaming files and folders, copying files and folders, and deleting files and folders. Just a reminder any time you see a command you should have a Power Shell open and should be typing it into the Power Shell!

Copying, Moving, Creating, and Removing Files and Folders

Use commands like mv, cp, mkdir, rm, and rmdir to manipulate files and folders. Be cautious when using these commands, as they can delete data permanently. For instance try out the following:

Making Directories

Let’s start in the user’s home directory and change into the “Documents” folder. cd ~ cd Documents

To create a new directory use the mkdir command it stands for make directory. This command takes an argument of a folder name or a path to a folder name. Now that you are in your documents you can make a directory called “sample_folder” mkdir sample_folder

When you create a directory the contents of the directory will be empty type: ls .\sample_folder

Quick Quiz!

Can you navigate into the sample folder and list the files and subfolders (there should be none) inside it?

You can also give the mkdir command a path. For instance change back to your home directory and then make a directory in your documents folder called another_folder that way you don’t have to change into your documents directory saves you a command. Remember you can do auto complete by hitting tab when typing in paths, type the first few letters of the path for instance ~/doc and hit tab and let the computer do the work for you! cd ~/ mkdir ~/Document/another_folder

Also notice you can do cd ~/ or cd ~ the slash separates sub-directories or files in your path and if there is nothing following it the computer will just ignore it.

Copying Files and Directories

To copy a directory we use the cp command, which stands for… you guessed it copy! cp takes an argument of two paths. First comes the path of the file(s) or folder(s) you want to copy, ie the source or sources and then the path of where you want to copy it to, ie the destination.

Copy a file from downloads

If you have a file in downloads you can use it or you can []click here to download this blank_file.txt file and Windows should put it in your downloads folder.

  1. Copy blank file from your downloads to your documents using absolute paths cp ~/Downloads/blank_file.txt ~/Documents
  2. Copy blank file from your downloads to your another_folder in the documents folders using a relative path for the source and an absolute path for the destination cd ~/Downloads cp ./blank_file.txt ~/Documents/another_folder
  3. Check and make sure it copied using the list command with a relative path! cd ~/Documents/another_folder ls -n . you could also type ls -n powershell will default to thinking you mean the current directory if you do not type a path.

Copy a directory using the -r option

You can copy a folder similarly to how you copy a file, however you will need to include the -r option, also known as the -r flag, or the recurse flag. The recurse flag will copy the directory and all the files and folders that may be in the directory too. You can not copy just a directory but not the files and folders in the directory, you have to copy it all! Not using the -r flag may work, but it is good practice to use it as other shells like Linux and Mac OS terminal require it.

  1. Copy your another_folder into your Downloads using absolute paths. cp -r ~/Documents/another_folder ~/Downloads
  2. Copy your sample_folder from your Documents into your Downloads folder using relative paths. cd ~/Documents cp -r ./sample_folder ~/Downloads

Copying multiple files and folders

You can use the copy command to copy multiple files and folders. The way the command is structured is the same you can separate multiple source paths with spaces. For instance to copy another_folder and the blank_file.txt to the sample_folder in your documents enter the command: cp ~/Documents/another_folder ~/Downloads/blank_file.txt ~/Documents/sample_folder

Moving files and folders

You can use the mv command to move files and folders. The move takes a source (or sources) path to the files and folders you want to move and also takes a destination path, ie where you want to move them to. The mv command will overwrite any files in the destination that are named the same as the source file and you can not recover this data if you accidentally overwrote an important file. The mv command can also be risky as unlike the cp the mv command does not copy the original file it moves it. Just like copy move can take multiple source paths if you want to move multiple files or folders at once. Unlike copy the mv command does not require the recurse flag, -r, to work with folders!

  1. Move the file blank_file.txt from your Downloads into your sample_folder in your Documents. There will no longer be a blank_file.txt in your Downloads you can list the files in your Downloads directory to confirm as it is now in your Documents/sample_folder. This move command will also overwrite the file you copied previously into sample_folder as they are the same you won’t really notice anything changed. mv ~/Downloads/blank_file.txt ~/Documents/sample_folder ls -n ~/Downloads ls -n ~/Documents/sample_folder
  2. List the contents of the subfolder sample_folder in your Documents. You should have a subfolder another_folder and the blank_file.txt in it. ls -n ~/Documents/sample_folder
  3. Move the copied sample_folder and the copied another_folder from your downloads to your Documents. Notice that as we already have a sample_folder and another_folder in our documents these got over written. If your sample_folder in your downloads had nothing in it then you should have an empty sample_folder in your Documents now. mv ~/Downloads/sample_folder ~/Downloads/another_folder ~/Documents ls -n ~/Documents/sample_folder

Renaming files and folders with mv and copy

In order to rename files and folders using the powershell you can use the move command. It works the same way except you can just use the current directory as the destination path and include the new file name as part of the path, if you do not include a new file name it will default to just moving it to the path you specified.

  1. Rename blank_file.txt in Documents/sample_folder to empty_file.txt Using relative paths: cd ~/Documents/sample_folder mv ./blank_file.txt ./empty_file.txt Using absolute paths: mv ~/Documents/sample_folder/blank_file.txt ~/Documents/sample_folder/empty_file.txt

You can also copy files and rename them at the same time too! In order to do that include an new file name at the end of your destination path. For instance… Rename a copy of empty_file.txt to null_file.txt: cp ./empty_file.txt ./null_file.txt


Deleting files with the rm command

In order to delete folders or files with the Power Shell you can use the rm command the rm command takes an argument that is the path to the file or folder you want to delete. If you want to delete a file in your current directory, type rm file_name where file_name is the file you want to delete. If you want to delete a file in another directory we type the path to the file you are deleting. If you want to delete a folder the command is the same and the argument is the path to the folder you want to delete, but you also must use the recursive option for instance: rm -r folder_name

Important Note Deleting files is a permanent operation it is not like deleting a file in the GUI where it goes to your recycling bin it is not possible (or rather very, very difficult) to recover a file or folder that you’ve deleted with the rm command. For this reason make sure that you have typed the right command! You would not want to accidentally delete all the files on your computer. That said don’t let this intimidate you or scare you away from using the rm command or other Power Shell commands. As Spiderman’s uncle once said, “With great power comes great responsibility.” So just be mindful and knowledgeable of what your commands are doing before you hit enter!


Autocompletion and Glob Patterns (wildcards)

As we learning in the getting started lesson power shell supporting autocompletion using the tab key. Pressing tab will cycle through the files in the directory you are located in based upon what you type. It will also add quotes around paths to files that have spaces. You can also use a wildcard symbol like * (matching zero or more characters) for pattern-based searching. These symbols are known as glob patterns there are more of them you can reads about online, but the one that is most often used is the * or asterisks symbol. It is very powerful, using the * we can list all of a specific file type in a directory for instance ls -n *.jpg will list all jpg files (a type of image file) in you current directory or you could list all folders or files that start with the prefix “computer” For instance if you typed ls -n computer* anything that started with computer would be output to the terminal. You can also use the * with other commands for instance deleting all files in directory would be rm *.* translating that into plain language would be something like: remove anything that starts with zero or more of any character then has a period in it and then ends with zero or more of any character. Things like wildcards are where one starts to really see the power of the command line shell.


Checks for Understanding

  1. Create a new folder in your documents.
  2. Rename that folder and move it up into your home directory in one command.
  3. Copy that folder from your home directory into your Downloads.
  4. Delete the folder you copied into Downloads in one command (no cd allowed!).
  5. Copy a file from you downloads folder and rename it and put it into your documents all in one command.
  6. Delete the file you just copied without changing directories to it.
  7. Make two folders in your Desktop folder name them this_folder_1 and that_folder_2 .
  8. Delete both of the folders using one rm command with one argument that uses the * wildcard.

NEXT STEPS

  • cat
  • echo

  • and » (redirection and append operator)

  • piping (command chaining)
  • running other applications from powershell

Additional Resources

For more in-depth learning and advanced usage of PowerShell, consider exploring the following helpful resources: