Scott Hanselman's ComputerZen.com

A number of people have mentioned to me that they didn't realize that Powershell is included by default in Windows 7. If you haven't yet jumped on the Powershell bandwagon, this is a good time. Powershell 2 includes a bunch of cool features like remoting (kind of like SSH) as well as a visual IDE for writing, editing and interactively debugging Powershell scripts.

Powershell great for system administration, but I mostly use it for quick and dirty "portable" apps that I don't feel like writing C#/VB for. Plus, I'm using .NET anyway, so it's all the same.

I wanted to download all my podcasts with Powershell, so I wrote this quick script in about 5 minutes. Other improvements I (or preferably you) could make to it could be: check the file size against the enclosure and re-download partials, rename the files to included a version of the title, include a progress bar.

Here's what I came up with. Perhaps you'll find it useful if you're not an iTunes/Zune person:

cd "C:\users\scottha\desktop\Hanselminutes Complete Download"
[Environment]::CurrentDirectory=(Get-Location -PSProvider FileSystem).ProviderPath
$a = ([xml](new-object net.webclient).downloadstring("http://feeds.feedburner.com/HanselminutesCompleteMP3"))
$a.rss.channel.item | foreach{  
    $url = New-Object System.Uri($_.enclosure.url)
    $file = $url.Segments[-1]
    $file
    if (!(test-path $file))
    {
        (New-Object System.Net.WebClient).DownloadFile($url, $file)
    }
}

Of course you'll want to change the first line and the RSS Feed URL as you like.

If you've never used Powershell before, note that it's locked down from running scripts be default. You'll need to run it as Administrator once and run

Set-ExecutionPolicy unrestricted

This opens it up to run scripts, but it's not only VBS, the scripts won't run if you double-click them. You need to run powershell then type the name of your script to run it:

.\myscript.ps1

You can always set the execution policy back if it bothers you.

Hope this primitive mass podcast enclosure downloader is useful.

I've got many many gigs of 640x480 video of the kids and family taken on my Flip Ultra and then HiDef video taken with a Creative Vado HD, my current favorite pocket video camera. There's also a bunch of random videos taken with whatever video-capable digital camera I might have had with me at the moment.

These are fantastic video cameras (especially the Vado) but unfortunately the output they produce aren't easily streamed to any Game Console like a PS3 or Xbox360.

There's a glorious open-source multi-platform video transcoder out there called HandBrake. There's also the more sophisticated Expression Encoder. I usually use these applications (both can be called from the command-line) when I need to encode videos.

I figured I'd just drag the whole folder over and magically these apps would happily encode these hundreds of files and all subdirectories. Both apps are fantastic for doing one file at a time, but when you want to do a thousand, things break down. I googled with Bing for a while then decided that the batch files and MacGyver solutions I was finding were silly. Why not make my own ridiculous solution that at least worked for me?

Even better, why not do it as a one line PowerShell script and see if it's useful to you, Dear Reader? Even better, perhaps you'll re-write it in the comments and one day it won't suck as deeply as it does now.

Regardless, this script is currently, happily chewing away at all my videos and even better, these versions are streamable to my Xbox360 from my Windows Home Server. Woot. The Wife is happy.

Here it is:

gci . *.avi -R | foreach-object { $newfile = $_.Path + $_.DirectoryName + "\" + $_.BaseName + "-convert" + $_.Extension; &"C:\Program Files (x86)\HandBrake\HandBrakeCLI.exe" -i "$_.FullName" -o "$newfile" --preset "Xbox 360" }

Eek! But what price my immortal soul?

You need PowerShell for this, if you don't already have it. If you have Windows 7, it's already installed!

This poorly written script takes every *.avi file in the current (.) folder, and all folders underneath it (-R), and for each of this files, creates a new filename with the word "-convert" inside. It then calls the HandBrake command line (yours may be in "C:\Program Files" so you might need to change that. It uses the Xbox360 preset.

After this runs, you'll end up with a whole pile of foo-convert.avi files that should/will stream from your machine to your Xbox360 if you are using the free Windows Media Sharing Services. You can also change that profile and convert all your phone for your phone, or whatever you like.

Here's a snapshot of a classic baby video shown on the big screen. Don't you want to come over for dinner now? You can watch slideshows of all our still videos and now hours of family movies. Woot! Works For Me.

PowerShell experts? I'm quite rusty, and I was just interested in the "Getterdone" version. How can we make it better? How about making it so it only updates files that haven't already been encoded?

My one-hundred-and-sixty-second podcast is up. Scott's at TechEd and bumps into Hal Rottenberg and Kirk Munro. Hal's a PowerShell IT guy and Kirk's a Powershell-focused Dev. What's new in PowerShell 2.0 and what's in it for the .NET developer or Windows power user?

Subscribe:

• Download: MP3 Full Show #162
• Play in your browser

Do also remember the complete archives are always up and they have PDF Transcripts, a little known feature that show up a few weeks after each show.

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As I've said before this show comes to you with the audio expertise and stewardship of Carl Franklin. The name comes from Travis Illig, but the goal of the show is simple. Avoid wasting the listener's time. (and make the commute less boring)

Enjoy. Who knows what'll happen in the next show?

In a few days the 2008 Scripting Games will come to an end. This is a yearly event that the Script Center does. There's a beginner and an advanced division and a bunch of deceptively hard problems. I was selected to be on of the "Guest Commentators (list here)" which really means they wanted me to solve one of the problems and provide the solution as an example. I'm not sure my solution is the best way, but it did solve the problem they assigned me.

My problem was Event 7: Play Ball! and I was to write a script that schedules all the games for a round-robin baseball tournament. The complete scenario is here, but in a nutshell:

"In a round-robin baseball tournament (or any kind of round-robin tournament, for that matter), every team plays each of the other teams in the tournament one time and one time only. For example, suppose we have a tournament with three teams (teams A, B, and C). In that case, the tournament would consist of the following set of games:

• A vs. B
• A vs. C
• B vs. C

See how that works? Team A plays Team B and Team C; Team B plays Team A and Team C; and Team C plays Teams A and B."

A few other wrinkles thrown in are that the games must be randomized, otherwise Team A will play too many in a row and you need to schedule six teams, A through F. Of course, to be clear, every team must pay every other team once and only once. Here's my solution, hacked together quickly.

#this only works with an even number of teams
cls
[array]$global:games = $nul
function rotateArray($a)
{
 $first, $rest = $a
 $a = $rest + $first
 return $a
}
function makeGames($a)
{
 $i = 0;
 while($i -lt $a.Length/2)
 {
  $global:games = $global:games + ($a[$i].ToString() + " vs. " + $a[$a.Length-1-$i].ToString())
  $i++
 }  
}
$a = "A","B","C","D","E","F"
$z = 0
while($z -lt $a.Length-1)
{
 makeGames($a)
 # hold on to the first one
 
 $first, $rest = $a
 #rotate the rest
 $rest = rotateArray($rest)
 $a = [array]$first + $rest
 $z++
}
#randomize games
$a = [collections.arraylist]$global:games
$r = $a.count..1 |% {$R = new-object random}{$R.next(0,$a.count) |%{$a[$_];$a.removeat($_)}}
$r

Doing this in PowerShell took my brain a while to get. Note the RotateArray method's use of multi-variable assignment to chop up he array into first and rest. That wasn't obvious to me as a C-guy for the last 15 years, but it made my solution simpler when I refactored and introduced it.

The solution (remember, it's randomized) will look something like this:

B vs. D
B vs. C
A vs. D
B vs. F
C vs. D
A vs. F
A vs. B
C vs. F
E vs. F
A vs. E
D vs. F
B vs. E
D vs. E
A vs. C
C vs. E

Enjoy. Here's the same solution in Perl from Jan Dubois and again in VBScript. Who wants to do the F# version and the Ruby version? What about just LINQ to Objects?

I was writing a PowerShell Script for the 2008 Window Scripting Games (are you in the games?) and I found writing a long complex script using only a text edit to be really tiring.

I blogged about a PowerShell IDE two years ago, but for whatever reason it didn't stick. I didn't start using it regularly and fell back to the command-line and notepad.

However, while I was writing scripts for the Games I got fed up with just the command-line. I went back to http://www.powershell.com and starting coding in the PowerShellPlus Editor. You can get it free. Schweet.

This IDE has come so far and it's a joy to use. It's got a debugger and intellisense and syntax highlighting. It's like SQL Analyzer, but for PowerShell. It's a great way to not only learn PowerShell but it's very powerful for advanced users. Seriously, go get it.

UPDATE with $50 off COUPON: From the comments: "So we have a special deal for loyal hanselman fans..For the next 2 weeks we will give $50 off our price of $129, giving you our PowerShell Suite for only $79.  However we've only set up the coupon code with google checkout, so you'll have to checkout through there. So basically add the item to your cart, and check out with Google checkout and use the coupon code: hanselman and you'll be on your way."

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