Lee Holmes - PowerShell Pocket Reference, 3rd Edition

• 2021-04-22: First Release

PowerShell has revolutionized the world of system management and command-line shells. From its object-based pipelines to its administrator focus to its enormous reach into other Microsoft management technologies, PowerShell drastically improves the productivity of administrators and power users alike.

When youre learning a new technology, its natural to feel bewildered at first by all the unfamiliar features and functionality. This perhaps rings especially true for users new to PowerShell because it may be their first experience with a fully featured command-line shell. Or worse, theyve heard stories of PowerShells fantastic integrated scripting capabilities and fear being forced into a world of programming that theyve actively avoided until now.

Fortunately, these fears are entirely misguided; PowerShell is a shell that both grows with you and grows on you. Lets take a tour to see what it is capable of:

• PowerShell works with standard Windows commands and applications. You dont have to throw away what you already know and use.

• PowerShell introduces a powerful new type of command. PowerShell commands (called cmdlets) share a common Verb-Noun syntax and offer many usability improvements over standard commands.

• PowerShell understands objects. Working directly with richly structured objects makes working with (and combining) PowerShell commands immensely easier than working in the plain-text world of traditional shells.

• PowerShell caters to administrators. Even with all its advances, PowerShell focuses strongly on its use as an interactive shell: the experience of entering commands in a running PowerShell application.

• PowerShell supports discovery. Using three simple commands, you can learn and discover almost anything PowerShell has to offer.

• PowerShell enables ubiquitous scripting. With a fully fledged scripting language that works directly from the command line, PowerShell lets you automate tasks with ease.

• PowerShell bridges many technologies. By letting you work with .NET, COM, WMI, XML, and Active Directory, PowerShell makes working with these previously isolated technologies easier than ever before.

• PowerShell simplifies management of data stores. Through its provider model, PowerShell lets you manage data stores using the same techniques you already use to manage files and folders.

Well explore each of these pillars in this introductory tour of PowerShell. If youre running any supported version of Windows (Windows 7 or later, or Windows 2012 R2 or later), Windows PowerShell is already installed. That said, a significant step up from this default installation is the open source PowerShellCore.

An Interactive Shell

At its core, PowerShell is first and foremost an interactive shell. While it supports scripting and other powerful features, its focus as a shell underpins everything.

Getting started in PowerShell is a simple matter of launching PowerShell.exe rather than cmd.exethe shells begin to diverge as you explore the intermediate and advanced functionality, but you can be productive in PowerShell immediately.

To launch PowerShell, click Start and then type PowerShell (or pwsh if youve jumped ahead!).

A PowerShell prompt window opens thats nearly identical to the traditional command prompt of its ancestors. The PS C:\Users\Lee> prompt indicates that PowerShell is ready for input, as shown in .

Figure P-1. Windows PowerShell, ready for input

. In this example, we use the pushd, cd, dir, pwd, and popd commands to store the current location, navigate around the filesystem, list items in the current directory, and then return to the original location. Try it!

Example P-1. Entering many standard DOS- and Unix-style file manipulation commands produces the same results you get when you use them with any other Windows shell

PS C:\Users\Lee> function prompt { "PS > " }PS > pushd .PS > cd \PS > dir Directory: C:\Mode LastWriteTime Length Name---- ------------- ------ ----d---- 5/8/2007 8:37 PM Blurparkd---- 5/15/2016 4:32 PM Chocolateyd---- 3/8/2020 12:45 PM DXLabd---- 4/30/2020 7:00 AM God---- 4/2/2016 3:05 PM Inteld-r-- 12/15/2020 1:41 PM Program Filesd-r-- 11/28/2020 5:06 PM Program Files (x86)d---- 5/12/2019 6:37 PM Python27d---- 3/25/2018 1:11 PM Strawberryd---- 12/16/2020 8:13 AM tempd-r-- 8/11/2020 5:02 PM Usersda--- 12/16/2020 10:51 AM WindowsPS > popdPS > pwdPath----C:\Users\Lee

In this example, our first command customizes the prompt. In cmd.exe, customizing the prompt looks like prompt $P$G. In Bash, it looks like PS1="[\h] \w> ". In PowerShell, you define a function that returns whatever you want displayed.

The pushd command is an alternative name (alias) to the much more descriptively named PowerShell command Push-Location . Likewise, the cd, dir, popd, and pwd