I'm quitting cmd

Aug 5, 2020

Background

Regarding operating systems I prefer Linux over Windows. Even though in my job I'm forced to use Windows. To make my work on Windows more pleasant I've been using Command-line alongside with vim, grep, AWK and other Unix/Linux tools.

Using cmd before Windows 10 was not a very visual appealing experience. It suppose to be just a rectangle box with a text and somehow they made it hard to read and write text. In Windows 10 cmd was visually improved. It started to look modern and more like other Linux terminals.

For the last five years I've been using Command-line on Windows 10. So what suddenly have changed my mind? PowerShell.

I always have been conscious that PowerShell exists but I've never give it a try. Why? To be honest because of it's horrible default dark blue background color. Recently I've got a task to extend some PowerShell script and I found out it's a great tool! And also I've configured ConEmu to use PowerShell as a default shell with the same appearance as cmd (black background and white JetBrains mono). That was the beginning of new chapter of my life.

What is PowerShell?

PowerShell is a framework from Microsoft consisting of scripting language and command-line shell built on top of .NET CLR. In 2016 PowerShell was moved to .NET Core which made it cross-platform and moreover it was open-sourced in August 2016 (under name PowerShell Core).

So basically it's a better command-line (not only) for Windows. How better? Let's find out.

Benefits of PowerShell over cmd

Here I've selected top features of PowerShell which in my opinion make it superior to standard cmd.

Pipes

For me most pain from using cmd comes from absence of Unix-like pipes. Unix pipe is an operator "|" (ASCII 124) and it takes an output of the previous process and treats it as input to the current process. It's a basis of Unix philosophy of composing programs introduced and implemented by Douglas Mcllroy and Ken Thompson around 1973 in Bell Labs. PowerShell got them!


ls -Recurse *.txt | Get-Content | Measure -l -w -c

The example above get a list of all text files from all sub-catalogs, get their content and finally count number of lines, words and characters.

Object-based

In traditional shells usual output from program is just text which can be input to another program which will produce another text output and so on. In this environment very common is combination of programs like grep, AWK and sed to deal with those streams of text.

PowerShell on contrary is object-based. Output of standard PowerShell utilities are .NET objects. To access object's properties and methods dot notation is used.


$fileList = ls
$file5 = $fileList[5]
Write-Host "File" $file5.FullName "was created" $file5.CreationTime

In the above example we've created $fileList (dollar sign have to precede variable name) which is an array of objects representing files. It's not an array of strings. It's an array of actual objects representing files. Next we defined $file5 which is an object representing 6th element of ls. Formally $file5 is of type FileInfo and have about fifty properties and methods. For example FullName and CreationTime properties which we used to print custom message but also methods like $file5.Open() which returns System.IO.FileStream which is regular .NET object representing a file stream. For C#, F# or VB programmers it's a very good news.


ls -Recurse *.go | Where-Object {$_.CreationTime -ge '2020-07-25'}

Another example displays how expressive it can be. This particular example lists all of files with .go extension from all sub-catalogs which was created after 2020-07-25. Notation $_ represents current value in the pipeline.

Integration with .NET

PowerShell is built on top of .NET thus integration with .NET is natural. Why that matters? For instance we can use C# standard libraries from PowerShell:


$rand = [System.Random]::new()
$rand.Next(10, 100)

We just used standard C# System.Random.Random object to generate pseudorandom integers. How cool is that? In particular you can use your C# functionalities for scripting! Sometimes that might be useful.

Another point is that you can define your own PowerShell cmdlets written in C# or F#.

Tab completion

PowerShell have a very good tab completion in comparison to cmd.

Aliases

PowerShell on default configuration have a very broad set of aliases for native functionalities. We have already seen ls "command". In fact ls is just an alias for Get-ChildItem cmdlet. Besides ls it has predefined other aliases - gci and dir. So both Linux and Windows cmd users won't have trouble to get a list of elements in given location. We can easy add new aliases for existing cmdlets using Set-Alias cmdlet.

There is one more advantage of having full name cmdlets and their aliases. When you're writing a PowerShell script you can use full name to increase readability and when you're just fooling around in terminal you can just use aliases for compactness and laziness of typing.

A cmdlet is a lightweight command that is used in the PowerShell environment. The PowerShell runtime invokes these cmdlets within the context of automation scripts that are provided at the command line.
— Microsoft Docs

Transition to PowerShell

Transition from Windows Command-line to PowerShell was very easy! Taking into account aliases and rather good (better then cmd) built-in help I've replaced cmd with PowerShell in one day. Without any effort! All of programs I've been using in cmd works without any difference in PowerShell. And what is most important now I feel that Windows is under my control and not the other way. More like on Linux. I very like that.

I've basically just started my journey with PowerShell but I'm sure that it will continue as long as I'll be forced to use Windows.

Summary

If you're Windows user or you're forced to use Windows and you want to get near Linux-like experience using terminal then go for PowerShell. Transition is effortless and you can easily change horrible default dark blue background color. And final gain is massive, especially if you're already a .NET developer. I think it is already one of my better choices regarding tooling, right after vim and AWK (not mentioning git which is obligatory nowadays).