In order to write a script, you first have to change your system security settings.

More subtly, because it's comparatively new it's not very dogfooded and there isn't a rich source of examples. UNIX systems usually have lots of shell scripts in /etc for you to learn from.

If the UNIX designers had chosen some other lowest common denominator, all of these diverse utilities would be communicating over that protocol instead of ASCII. The choice to use "text" came first and the ecosystem came afterward.

"Text" makes a good lowest common denominator because it's low. Everything, including humans looking at it, can deal with text. Essentially all programming languages on all platforms provide basic primitives analogous to getline(), find_first_of(), substr(), etc. You can take text from Unix and easily do something useful with it on any arbitrary platform.

MSIL assumes an entire infrastructure that isn't universally available. You can't take MSIL from Windows and easily do something useful with it on any arbitrary platform. It requires you to have a solid .NET virtual machine for your operating system, an API for dealing with MSIL, bindings for that API in every language you want to use, etc.

There is nothing analogous to convert MSIL to. EBCDIC and ASCII both have a representation for 'A'. Only .NET has "Microsoft.Win32.Registry.CurrentUser.CreateSubKey()".

In Linux/Unix I can also pipe audio to /dev/audio for example. And image processing through a sequence of steps by pipes is quite often done. Are these objects coming with default metaparameters to make piping easier? Or are there other things implemented that might be cool?

In UNIX, you have bytes, and the underlying system doesn't know what they represent. Most tools assume they're ASCII or UTF-8 (or whatever) encoded text, but that's all they agree on. In practice, you're working almost always working with structured data - tables or lists or mappings - but you have to remember that for the output of this program, you want to cut on '=' and take -f4, and first you need to pipe it through head and tail to clean up some junk output[1], and this other thing for that program, and whatever.

[1] This is a way to get the `time` field from the output of `ping`.

That's because the object pipeline is functionally analogous to function chaining within a single runtime like in Python or Ruby, not streaming data between arbitrary executables like in Unix pipelines.

This would be a lot clearer if PowerShell advocates compared it to things that it's actually functionally analogous to, but they are trying to position it as a Unix shell competitor.

No it is not. See my response below.

The fact stands, cmdlets can be implemented as .NET classes, but they can also be implemented through script (i.e. not .NET classes) or through manifests where cmdlets are generated for WMI/CIM classes.

I don't know why you continue to ignore this, or even why it is important. I point out that you are incorrect and point to a authoritative source that demonstrate the point.

The relevant section of the PowerShell section:

--- ... A module can contain one or more module members, which are commands (such as cmdlets and functions) and items (such as variables and aliases). The names of these members can be kept private to the module or they may be exported to the session into which the module is imported. There are three different module types: manifest, script, and binary. A manifest module is a file that contains information about a module, and controls certain aspects of that module's use. A script module is a PowerShell script file with a file extension of ".psm1" instead of ".ps1". A binary module contains class types that define cmdlets and providers. Unlike script modules, binary modules are written in compiled languages. Binary modules are not covered by this specification. Windows PowerShell: A binary module is a .NET assembly (i.e.; a DLL) that was compiled against the PowerShell libraries. ---

I will point out when your claims about PowerShell are incorrect. It's an opportunity to learn something. Please address the topic, not the poster.

Nope. The problem is that you searched for confirmation that cmdlets was "just" .NET classes (I really don't get why that is important), and then you dive into documentation for C# programmers and point out how the documentation for C# programmers is telling the C# programmer that if he wants to create a cmdlet he can do it with a C# class. D-oh!

When I point to the PowerShell specification and demonstrates how it does not claim that cmdlets are .NET classes you ignore it.

I point out how it enumerates the 3 different ways to make cmdlet modules: Binary, script and manifest, of which only the binary module variety implement cmdlets as classes.

You could equally well claim that Web Services are just MVC Controllers, because in the documentation for MVC I can find out how to implement web services using MVC controllers.

> ... and they exist within the .NET runtime, which is the relevant issue

Why? If the .NET runtime has become sediment to the point where the OS is always distributed with the runtime, where important OS functions (like troubleshooting) is implemented using the runtime, where remote administration is based on the runtime, at what point do you accept the runtime as part of the OS?

.NET IS part of Windows now, has been since Windows 7 SP1 (IIRC). Troubleshooting packs, guides etc. are written using PowerShell. When your network gets the hiccups, and Windows proactively offers to troubleshoot the network connection, it is PowerShell that is running underneath. The new PackageManager is PowerShell based.

> Thank you, however, for providing yet another demonstration of how PowerShell advocates consistently resort to handwaving, obfuscation, and false claims in order to try to pretend PowerShell is functionally different than it actually is.

No need for snide remarks. I stand by all of my claims. It is you who selectively quote C# programmers documentation out of context. All you have proven is that if a C# programmer wants to create a cmdlet using C#, he must implement it using a class.

Pipelines in Unix shells use OS-level functionality to connect standard streams of data, often encoded as text, between arbitrary executables written in any language.

The reason this is confusing is because one of the main tactics used in PowerShell promotion is to disingenuously compare PowerShell's "object pipeline" to Unix pipelines in order to try to make it appear to be more novel than it is, when they should be comparing it to what it's functionally equivalent to, which is function chaining within a single runtime.

If PowerShells pipelines are merely equivalent to function chaining, then you should have no problem replicating the following very simple pipeline with function chaining in Ruby, Python or JavaScript:

    cat log.txt -wait | sls "error"

But I am curious: Why is it important whether the pipelines could be implemented using function chaining or not? PowerShell is a shell where I interact with the system through commands. Yes - those commands are not the typical Unix executables - but they act as commands within the shell

Is your problem that it is not a Unix shell? You could equally well say that Unix shell pipelines are just processes connected by file descriptors. That is factually correct but does not represent the true utility of pipelines.

PowerShell pipelines are not file descriptors. PowerShell commands do not execute in separate processes. But PowerShell commands are versatile and can be combined in a way analogous to Unix shell pipelines where the output of one command is consumed and acted upon by the next command.

The object of a operating system command line shell is to expose the operating system features to the user of the shell. Why does it matter whether it uses Unix file descriptors. Even if PowerShell pipelines were equivalent to "just" chained functions, why does it matter?

I get the point that you need the .NET runtime to run PowerShell, because it is implemented using .NET. At what point do we consider a runtime part of the operating system. When it is intrinsically distributed with the operating system and cannot be uninstalled?

Of course, this kind of piping is present in nice languages that precede the PowerShell.

A one page Lisp macro will give you a left-to-right syntactic sugar for filtering. Clojure has a threading operator, Ruby has cascades of dots: object.{ blah }.foo().bar() ... and so on.

Non-ASCII has been supported for a long time.

I used "ASCII" instead of "text" to stress that "text" is just a protocol like anything else. The UNIX I'm running is set to use UTF8.

PowerShell's object pipeline is functionally analogous to function chaining in languages like Ruby, Python, and JavaScript, not Unix pipelines. PowerShell's object pipeline does not exist outside of the .NET runtime and you can not stream objects between arbitrary executables outside of the .NET runtime.

You can't compare an apple to an orange and say one is "objectively better," no matter how hard PowerShell advertisers try to pretend their apple is an orange.

No, in those languages function results are bound upon returning from the function. PowerShell's pipeline would be more like function chaining where each function is a co-routine that can yield partial results, which would make it considerable more complicated.

So your attempt at trivializing PowerShell fails from the start.

For your information, here is roughly how a PowerShell pipeline is set up, processed and torn down:

1. BeginProcess is invoked for each command in the pipeline, starting with the last command of the pipeline, working towards the first. When each command is initialized this way, it can start receiving objects from preceding command on the pipeline. Each command may start produce objects already during this phase, as all subsequent commands are ready to process them. If it produces objects, ProcessRecord of the subsequent command is invoked immediately. 2. ProcessRecord is invoked on the first command of the pipeline. If it yields objects, ProcessRecord of the subsequent command is invoked for each object, thus "pushing" objects through 3. EndProcess is invoked for the first command of the pipeline. It it yields objects, ProcessRecord of the subsequent command is invoked for each object. When EndProcess completes for the first command of the pipeline, EndProcess is invoked for the subsequent command and so forth until EndProcess has been invoked for all commands of the pipeline.

As you can see, each cmdlet has 3 phases: initialization, processing and completion. All cmdlets (functions?) become active at the same time, with the control flow passing to each command (function?) multiple times during each phase. This can be implemented in any turing complete language, but function chaining is a lame attempt at trivializing it. Throw in reactive sequences and it may get closer.

Consider how Sort-Object (alias sort) is implemented: It does nothing during BeginProcess, during ProcessRecord it adds to an internal collection but does not yield any objects (yet), during EndProcess it sorts and yields all of the collected records. This is clearly analogous to how sort in byte/text stream is implemented: When the process starts it does nothing but initialize and starts listening on stdin, for each "line" on stdin it adds to an internal collection, and when stdin is closed it sorts the collection and writes the "lines" to stdout. 3 phases.

Even so, it doesn't really matter how it is implemented, a shell is inherently about how you interact with the shell.

> PowerShell's object pipeline does not exist outside of the .NET runtime and you can not stream objects between arbitrary executables outside of the .NET runtime.

You are locked in the Unix view of the world and is unable to consider that long standing assumptions about "the way to do it" may need a refresh. If you want to leverage objects for system management then yes, you need a system-wide object model. Unix was not built with an object model. Windows was sort-of build with an object model (handles) but it is not versatile enough as a system-wide management model.

However, the good thing about objects is that they are abstractions which can easily wrap existing operating system concepts, such as files, processes, access control lists, drivers, users, groups, network connections etc. .NET is a mature object model and with a lot of tooling. Building PowerShell so that the abstractions over network adapters, users etc become represented by .NET classes enable a lot of tooling and infrastructure right from the beginning.

No matter how much you want to try to talk around it, PowerShell is a .NET CLI, the object pipeline exists within its .NET runtime, and the commands are instances of .NET classes. Unix shells work primarily with arbitrary executables outside of the shell runtime using OS system calls to create pipelines with standard streams.

Here's the cold hard fact stated yet again: PowerShell's object pipeline is functionally analogous to function chaining in languages like Ruby, Python, and JavaScript, not Unix pipelines.

Ok, what then is the functionally analogous function chaining of Ruby, Python or JavaScript to the following:

    cat log.txt -wait | sls "error"

They are honestly too long.

I haven't used inforno-shell, es or rc, so can't comment on them directly. That said, if they are easily comparable to bash, ksh, etc, then you probably owe it to yourself to see what powershell is about and why it's fundamentally different.

I specifically contrasted them against Bourne or C-like shells, so I thought that much was clear that they are not.

I have tried PowerShell. I think this comment summarizes it well: https://lobste.rs/s/vzjalp/why_i_dislike_systemd/comments/sh...

If you want to run a script simultaneously on a number of hosts, you use the Invoke-Command cmdlet (or it's alias icm).

If you want to stop a process, you use Stop-Process (or it's alias kill).

To copy files or directories you use the Copy-Item cmdlet (or one of it's aliases cp and copy).

Hence, to stop WINWORD on a host1, host2 and host3 and then copy a directory from host0 to each of them, you would write:

    icm host1,host2,host3 {kill -name WINWORD; cp \\host0\C$\source C:\dest }

The commenter is correct that you cannot start an application in another session from remote. However, this is a security restriction that prevents cross-session contamination and shatter attacks. It is a (security) limitation of Windows, not of PowerShell.

Under Windows, all services run in session 0, the interactive user run in session 1, and if more users log on (e.g. remotely through PowerShell) they are each created in their own session. Windows put severe restrictions on what programs can do cross-session - even if the processes run under the same user account: They cannot send messages, interact with the desktop windows, inject code, start threads etc.

The commenter also alludes to other security settings that you'll encounter when you first start using PowerShell: - Execution of script files are disabled by default. You need to use the Set-ExecutionPolicy cmdlet to allow script execution, and for desktop editions you need to enable remote management. Both has secure-by-default values.

To enable script execution:

    Set-ExecutionPolicy RemoteSigned LocalMachine

To enable remote management run this command:

    Enable-PSRemoting

By asking if inferno-shell and friends were easily comparable with C-like shells I was attempting to determine if they were additionally hard to compare with powershell, and infer from that your unfamiliarity with powershell. That, obviously, was a stretch.