Why do such a thing? Well, if you’ve created your own aliases for commands and you try to give someone your ps1 script file, it will not run because they have not got the same aliases defined as you. Also, scripts that use fully-resolved names like “Get-ChildItem” are more readable for a newcomer to PowerShell than one that is using the unix-like “ls" alias for example. "Get-ChildItem" leads quite directly to the MSDN documentation, but "ls" might lead you anywhere. Before you publish a script online somewhere for the world to use, it’s important that you try to remove any aliases and replace them with the native command names.

Doing this kind of thing has been talked about before but it was always a very difficult thing to do with PowerShell v1.0, what with the lack of BNF documentation describing the grammar etc. Thankfully, it's a lot easier to do with PowerShell v2.0 (currently at release CTP2) because the team has exposed the Tokenizer for use in scripts. There's been suprisingly little use of it so far, so I figured I'd start the ball rolling with a series of articles based around it. So, let's look at an example script that uses aliases and put it through the meat grinder:

As you can see, it spits out the expanded script to the output stream. The informational messages are written to the host, so they won't interfere if you redirect the output to a file like: .\resolve-aliases.ps1 in.ps1 > out.ps1

Here's the Resolve-Aliases.ps1 script itself:

Of course, this requires PowerShell v2.0 CTP2. Next in the series, I'll give you a script to check your ps1 scripts for backwards compatibility against PowerShell 1.0. That should be handy for those naughty admins out there who despite all the warnings have installed v2 in production.

Someone on a private mailing list I'm on lamented the problem with powershell's '>' redirection operator defaulting inflexibly to use unicode for encoding the output file. This is not very compatible for NT's ancient console subsystem which works best with ASCII data. Fortunately, there's an easy workaround to fix this:

Due to the magic of command discovery and the fact that > really does use out-file, you can "fix" this by placing the following in your $profile:

function out-file($FilePath, $Encoding, [switch]$Append) {
$input | microsoft.powershell.utility\out-file $filepath -encoding ascii `
     -append:$append
}

From now on, > will be forced to use ASCII encoding. This works because functions have higher precedence than built-in commands in powershell's command discovery search.

UPDATE: Rather annoyingly, I'm informed that this particular workaround doesn't work on v1.0 of PowerShell. I tested the above on v2.0CTP2 only. Doh.

Just another quick-fix post for any readers’ benefit. I have been using MOSS on Windows 2008 Server on VMWare for a while now and the display has always been sluggish and choppy even though VMWare tools is up-to-date and installed. I decided to take a quick peek at the display properties to see if perhaps hardware acceleration is off or something like that and I noticed that the display driver was “Standard VGA Display.” I thought to myself, “Shouldn’t that be a VMWare display driver?” so I clicked properties and drilled down to the “Update Driver…” dialog. Clickety-click and hey presto, it finds a newer driver, namely “VMWare SVGA II” and installs it. Display is now much better. On other guest OS’s like Win 2003 etc, VMWare tools installation updated the driver for you, but this time it didn’t. Not sure why.

One remaining problem I have is that the mouse is dodgy and sometimes the host mouse pointer gets de-synced with the guest’s. Anyone got that problem?  Fixed by starting device manager and going through nearly the same drill as the display driver. I manually chose “VMWare Pointing Device” and rebooted, replacing the default ps/2 mouse driver.

Update:

After I rebooted, it was still a little sluggish. Then I remembered that by default, hardware acceleration is only at one notch up. So, push it up to full!

MoW poked at me, so I guess I can’t let the crazy dutchman down:

How old were you when you started using computers?

10 or 11

What was your first machine?

An Amstrad CPC 464 with Green screen.

What was the first real script you wrote?

I vaguely remember being delighted at having a rocket (Chr$(239)) ascend the Amstrad’s screen when I figured out that STEP –1 was the key in getting a for/next loop to count backwards.

What languages have you used?

• Powershell, VBScript, JavaScript, Tcl, Perl, Batch/4NT
• Z80A, 8088/8086 (NECv20/v30) assembler
• Basic, Turbo Pascal, Turbo C, C++, Java, C#, VB.NET

I’m a bit of a jack-of-all-trades when it comes to development. The list above is just what I can remember

What was your first professional Sysadmin Developer gig?

After helping out a friend’s dad put together a training course for Visual Basic 3.0, I then managed to blag a job coding Ireland’s first ever major e-commerce site using MS Merchant Server 1.0 (which predated ASP 1.0) for a leading ISP.

If you knew then what you know now, would you have started in IT?

I might have started a little bit earlier even!

If there is one thing you learned along the way that you would tell new Sysadmins (or Devs), what would it be?

Just one thing? Learn Regular Expressions as it will pay you back ten-fold for whatever time you put into it.

What is the most fun you have had scripting?

There’s only one answer here: writing extensions for PowerShell.

This particular branch of the meme ends here as I don’t think I can tag anyone who hasn’t been tagged already.

Just a quick one for the frustrated searchers out there. If you've recently installed the SP1 beta for Visual Studio 2008 (or just the 3.5 sp1 beta alone), and you find that you have serious difficulty using SharePoint Designer 2007 against a remote instance of SharePoint running in a VM (or a physical machine) that doesn't have the SP1 Beta bits, you know what to do. My SPD would refuse to load the master page from my virtualized SharePoint instance until I had installed .NET 3.5 SP1 Beta onto the virtual machine also. Just so you know!

In the spirit of "tidying things up," and pushing out nearly-there projects, I turned my attention to http://www.codeplex.com/PSMobile. I have a number of seriously annoying (to myself and people around me) habits, one of which is having a hard time finding the motivation to get that last 1% bit of work done. I am trying to kill bludgeon that habit, and this is fruit number #2 of that attempt at self-correction. I have some other important out of band work that I need to complete, but I find I cannot concentrate on that until these personal projects that have been niggling me for ages are dealt with. Anyway, lets dispel a couple of questions with a screenshot:

Requirements

• ActiveSync 4.2 or higher (or Windows Mobile Device Centre 6.0+ on Vista) Download
• A Windows Mobile device (PocketPC/SmartPhone 2002, 2003, 2003SE, Windows Mobile 5, 6 or 6.1)
• Windows PowerShell 1.0 or 2.0 (CTP) Download

Features

• Copy, Move, Delete items between folders on your device (including Storage Card) with standard PowerShell Cmdlets
• Move/Copy files to/from your device and your desktop with ConvertTo-WMFile and ConvertFrom-WMFile
• Get device information and manipulate and explore the registry with a rich device object returned from Get-WMDevice
• Invoke-Item against remote items to or execute or trigger their associated applications
• Invoke-Item with -Local switch to attempt to execute a remote file in the context of your local desktop (e.g. office docs or images/videos)
• New "Mode" attributes specific to Windows Mobile file attributes: (I)nRom, Rom(M)odule
• File/Folder objects' attributes can be modified with .Attributes properties just like FileInfos etc.
• Tab completion with MoW's PowerTab Download

File Manipulation

A picture's worth a thousand words.

Cmdlets and Definitions

Here's a table of the syntax for the included Cmdlets.

* These Cmdlets that accept a path will bind to pipeline input via PSPath property name.

If you've got any problems, suggestions or ideas, please post into the discussions board on the web site. Have fun!

I took a few hours yesterday to "tidy up my room" so to speak, so I built a nice MSI installer, updated the help, CodePlex Wiki and examples and closed all bugs. This is probably the final release now that PowerShell 2.0 CTP2 has introduced support for eventing, so thanks for all the support.

New Features

• Multiple named queue support and default queue with -QueueName parameter
• Better COM support, window message pumping etc.
• NoFlush / Peek parameter support for queue reading
• Get-EventQueue command added for viewing queues and their message counts.

Cmdlet Name Changes

• Get-Event -> Read-Event
• Connect-EventListener -> Connect-Event
• Disconnect-EventListener -> Disconnect-Event

Additionally, several niggling bugs closed (including the one where read-event -wait would return immediately with no events).

http://www.codeplex.com/pseventing

For an advanced example: Foreground / Background Swappable Downloads In PowerShell.

UPDATE May 26th: You must run PowerShell v2.0 CTP in STA mode for this to work. Start the shell, then run "powershell -sta" from the command line to start a new version of the shell in "single thread apartment" mode (STA). This is required for WPF to work correctly.

That is a bit of a mouthful of a title for this post but it's the best I could come up with. This post takes some of James' scripty bits and Jaykul's scripty bits and shows you how to create a countdown timer written in PowerShell script that runs in the background without blocking input. Just like Jaykul's original clock, you can drag it around and right-clicking it will close it. His version was the current time and it also showed some system resources. I changed it into a countdown and removed the other nested graphs. When it hits 00:00:00 it turns red. Here's what it looks like:

Here's the source of invoke-background.ps1:

Next, here's the modified clock script:

...and finally the modified clock.xaml file:

Important: you'll need to save all files into the same directory and fix up the path to the clock.xaml file in the start-countdown.ps1 script.

Have fun!

This question has been asked in various ways over the last few years and I don't believe an answer that suits everyone has been proffered yet. I think this is part of a broader problem space that needs to be solved, one that I (and many others) have spent a bit thinking about -- for me personally, it's been mostly in the pub strangely enough, usually with a pint in hand -- and while I don't profess to have the answer, I do spent most of my powershell time tinkering with providers and have some views on this

Firstly, if you haven't seen this suggestion I've raised on connect (Allow providers other than the filesystem provider to surface commands) then take a gander at it now. It suggests allowing providers other than the FileSystemProvider to surface commands by using a new ProviderCapabilities flag. For those not able to read this suggestion, the bottom line is that currently one can execute a command on the filesystem by using the following syntax:

ps c:\> .\test.bat
hello, world

However, if you had another provider that linked into a mobile device, the amazon s3 service or MSL skydrive (when are they going to release an API?) for example, you would allow execution of commands with the same syntax, e.g.

ps skydrive:\> cd ppts
ps skydrive:\ppts> .\mydemo.ppt
The term '.\mydemo.ppt' is not recognized as a cmdlet, function, operable program, or script file. Verify the term and try again.
At line:1 char:8
+ .\mydemo.ppt <<<<

As you can see, this doesn't work.

What's important is having the same experience with similarly capable providers; e.g. those that can host executable content. Yes, you can implement support for invoke-item, but it's a bit discordant. One of the nicest features of powershell (and sometimes the most confusing) is that all providers - variable, function, environment, filesystem etc all hook into the same framework. There are some philosophically irksome differences like the fact that the  variable drive is the "default" provider, since dollar-qualified expressions are assumed to point there if not qualified with a drive name:

ps c:\> $host
Name             : ConsoleHost
Version          : 1.0.0.0
InstanceId       : 9d8a29bf-3d84-4ce6-8651-e0c72afb404b
UI               : System.Management.Automation.Internal.Host.InternalHostUserInterface
CurrentCulture   : en-CA
CurrentUICulture : en-US
PrivateData      : Microsoft.PowerShell.ConsoleHost+ConsoleColorProxy

so let's give a drive name this time:

ps c:\> ${c:test.bat}
@echo hello, world

This is a lot easier to understand once you realise that the '$' prefix is a grammatical shortcut into the IContentReader/IContentWriter interfaces on every provider; Much easier than just blindly committing to memory the method to read a variable and the method to read a file (imho). Once you introduce this capability into other providers, you then have to address ye olde $env:path variable. Currently this variable is imported from the system environment. The system, aka Windows, knows nothing about powershell and its drives. When using Get-Command, the search order for discovering commands is:

Aliases, Functions, Cmdlets, Scripts, Commands located in the directories specified by the Path environment variable, External scripts.

As we can see, Commands (5) are discovered via the $env:path variable. The other items (apart from 3 - cmdlets) all live in a flat namespace, so there's no path involved there.  I'd love if somehow it were possible to add any powershell path to this variable, even if they were limited to drive-qualified paths:

ps c:\> $env:path
c:\windows; c:\windows\system32; ...; s3:\utilities; "mobile:\storage card"; ...

Perhaps this information could be persisted inside PowerShell only so when the shell is exited, the path environment variable remains unchanged when viewed from the external windows system. This might mean that PowerShell paths would have to be appended in your profile at each load, but this isn't a bad thing either, IMO. So finally, on to the crux of the matter: disambiguation of identically named Cmdlets. Ultimately I don't believe there is a magic answer. This is solved in Windows by using the path variable, and so I believe it isn't such a bad idea to solve it with a path variable in powershell too. Behold $env:cmdletpath

ps c:\> $env:cmdletpath
Microsoft.PowerShell.Core; Microsoft.PowerShell.Host; Microsoft.PowerShell.Management; Microsoft.PowerShell.Security; Microsoft.PowerShell.Utility; VMWare.Commands.Utility

It's simple. It's optional. Snap-in qualified commands would continue to work, overriding the cmdlet search path. Instead of having to alias multiple commands when using a snapin that replaces a suite of built-in cmdlets, you can just re-jig the search path. Done. It's not the answer to everything, but it sure would make life a bit easier, no?