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Permanently Add Path to System PATH Environment Variable in PowerShell

param([Parameter(Mandatory = $true)] [string] $Path);
$FullPathOriginal = (gp "HKLM:\System\CurrentControlSet\Control\Session Manager\Environment").Path;
if (!($FullPathOriginal.split(";") | ?{ $_ -like $Path })) {
    sp "HKLM:\System\CurrentControlSet\Control\Session Manager\Environment" -name Path -value ($FullPathOriginal + ";" +
 $Path);
}

PowerShell Equivalents for JavaScript Array Functions

URI Percent-Encoding Ignorance Level 1 - Purpose

As a professional URI aficionado I deal with various levels of ignorance on URI percent-encoding (aka URI encoding, or URL escaping).

Worse than the lame blog comments hating on percent-encoding is the shipping code which can do actual damage. In one very large project I won't name, I've fixed code that decodes all percent-encoded octets in a URI in order to get rid of pesky percents before calling ShellExecute. An unnamed developer with similar intent but clearly much craftier did the same thing in a loop until the string's length stopped changing. As it turns out percent-encoding serves a purpose and can't just be removed arbitrarily.

Percent-encoding exists so that one can represent data in a URI that would otherwise not be allowed or would be interpretted as a delimiter instead of data. For example, the space character (U+0020) is not allowed in a URI and so must be percent-encoded in order to appear in a URI:

1. http://example.com/the%20path/
2. http://example.com/the path/

In the above the first is a valid URI while the second is not valid since a space appears directly in the URI. Depending on the context and the code through which the wannabe URI is run one may get unexpected failure.

For an additional example, the question mark delimits the path from the query. If one wanted the question mark to appear as part of the path rather than delimit the path from the query, it must be percent-encoded:

1. http://example.com/foo%3Fbar
2. http://example.com/foo?bar

In the second, the question mark appears plainly and so delimits the path "/foo" from the query "bar". And in the first, the querstion mark is percent-encoded and so the path is "/foo%3Fbar".

Command line for finding missing URLACTIONs

I wanted to ensure that my switch statement in my implementation of IInternetSecurityManager::ProcessURLAction had a case for every possible documented URLACTION. I wrote the following short command line sequence to see the list of all URLACTIONs in the SDK header file not found in my source file:

grep URLACTION urlmon.idl | sed 's/.*\(URLACTION[a-zA-Z0-9_]*\).*/\1/g;' | sort | uniq > allURLACTIONs.txt
grep URLACTION MySecurityManager.cpp | sed 's/.*\(URLACTION[a-zA-Z0-9_]*\).*/\1/g;' | sort | uniq > myURLACTIONs.txt
comm -23 allURLACTIONs.txt myURLACTIONs.txt

I'm not a sed expert so I had to read the sed documentation, and I heard about comm from Kris Kowal's blog which happilly was in the Win32 GNU tools pack I already run.

But in my effort to learn and use PowerShell I found the following similar command line:

diff 
(more urlmon.idl | %{ if ($_ -cmatch "URLACTION[a-zA-Z0-9_]*") { $matches[0] } } | sort -uniq) 
(more MySecurityManager.cpp | %{ if ($_ -cmatch "URLACTION[a-zA-Z0-9_]*") { $matches[0] } } | sort -uniq)

In the PowerShell version I can skip the temporary files which is nice. 'diff' is mapped to 'compare-object' which seems similar to comm but with no parameters to filter out the different streams (although this could be done more verbosely with the ?{ } filter syntax). In PowerShell uniq functionality is built into sort. The builtin -cmatch operator (c is for case sensitive) to do regexp is nice plus the side effect of generating the $matches variable with the regexp results.

clip.exe - Useful tool I didn't know shipped with Windows

When you run clip.exe, whatever comes into its standard input is put onto the clipboard. So when you need to move the result of something in your command window somewhere else you can pipe the result into clip.exe. Then you won't have to worry about the irritating way cmd.exe does block copy/pasting and you avoid having to manually fixup line breaks in wrapped lines. For instance, you can put the contents of a script into the clipboard with:

more cdo.cmd | clip

I've got a lot of stuff dumped in my bin folder that I sync across all my PCs so I didn't realize that clip.exe is a part of standard Windows installs.

Nice for avoiding the block copy in cmd.exe but I'd prefer to have the contents sort of tee'd into the clipboard and standard output. So TeeClip.ps1:

$input | tee -var teeclipout | clip;
$teeclipout;

PowerShell Script Batch File Wrapper

@echo off
if "%1"=="/?" goto help
if "%1"=="/h" goto help
if "%1"=="-?" goto help
if "%1"=="-h" goto help

%systemroot%\system32\windowspowershell\v1.0\powershell.exe -ExecutionPolicy RemoteSigned -Command . %~dpn0.ps1 %*
goto end

:help
%systemroot%\system32\windowspowershell\v1.0\powershell.exe -ExecutionPolicy RemoteSigned -Command help %~dpn0.ps1 -full
goto end

:end

@echo off
if "%1"=="/?" goto help
if "%1"=="/h" goto help
if "%1"=="-?" goto help
if "%1"=="-h" goto help

%systemroot%\system32\windowspowershell\v1.0\powershell.exe -ExecutionPolicy RemoteSigned -Command . %~dpn0.ps1 %*;(pwd).Path 1> %temp%\%~n0.tmp 2> nul
set /p newdir=

Windows 7 Accelerator Platform COM / C# Interop

For a new project I'm working on involving IE's installed Accelerators and OpenSearch search providers via the Windows 7 Accelerator Platform, I've created a C#/COM interop class for those APIs.

Download the osinterop.cs interop file here.

DVD Ripping and Viewing in Windows Media Center

I've just got a new media center PC connected directly to my television with lots of HD space and so I'm ripping a bunch of my DVDs to the PC so I don't have to fuss with the physical media. I'm ripping with DVD Rip, viewing the results in Windows 7's Windows Media Center after turning on the WMC DVD Library, and using a powershell script I wrote to copy over cover art and metadata.

My powershell script follows. To use it you must do the following:

1. Run Windows Media Center with the DVD in the drive and view the disc's metadata info.
2. Rip each DVD to its own subdirectory of a common directory.
3. The name of the subdirectory to which the DVD is ripped must have the same name as the DVD name in the metadata. An exception to this are characters that aren't allowed in Windows paths (e.g. <, >, ?, *, etc)
4. Run the script and pass the path to the common directory containing the DVD rips as the first parameter.

Running WMC and viewing the DVD's metadata forces WMC to copy the metadata off the Internet and cache it locally. After playing with Fiddler and reading this blog post on WMC metadata I made the following script that copies metadata and cover art from the WMC cache to the corresponding DVD rip directory.

Download copydvdinfo.ps1

TiMER

An excellent movie I'd never heard of. An entertaining and humorous sci-fi indie romance comedy. It stars Emma Caulfield (who I recognize as Anya from Buffy the Vampire Slayer) who obsesses over her timer, an implanted device that counts down to when she'll meet the love of her life. Thematically its similar to Eternal Sunshine of the Spotless Mind which similarly adds a scifi device to society in order to examine the value of failed relationships on a persons life.

Cheap Multiplayer Tricks for New Super Mario Bros. Wii

The New Super Mario Bros. Wii is a great game. Its the fun of old school Mario with the addition of great graphics and the kind of multiplayer I've wanted for Mario since playing the original as a child: its got up to four player simultaneous cooperative multiplayer. I recommend it to anyone who has enjoyed Mario in the past. Watch this amazing video of level 1-3 you can unlock in the game.

As noted elsewhere, multiple players attempting to navigate platforms, grab power ups, and throw turtle shells creates new challenges but along with that there's new ways to be incredibly cheap.

Jumping Higher

A second player means a head one can jump on to reach higher locations. Jump on your friend's head at the apex of their jump while holding down the jump button yourself for maximum jumping. In the game you can also grab other players and hold them over your head. This is useful for reaching the top of the flagpole at the end of levels. On that same line, if the player you grab has a flying cap you can now use them to fly in the same manner you would use a flying block which makes it easy to get two players to the top of the finish flagpole if only one of you has a flying cap.

Power-Ups

Normal power-up blocks now spawn enough power-ups for everyone. A mushroom is spawned for each small player and full power-ups for the rest, except in the case everyone is small: then one of the power-ups is a full power-up. If there's two players and you're both small, the full power-up always jumps out of the block to the right. Some hidden power-up blocks only give out one power-up and in that case its a mushroom or not based on the player who hits the block - so be sure that a big player hits that if you have one.

Death & Bubbles

When a player dies but at least one other player lives the dead player comes back in a limbo bubble from which they must be released before they may play again. Because of this, in a tough spot you can send one player in and leave a second behind. If the first dies you don't lose your place in the level and the first comes back in a bubble ready to try again. For instance, if you're trying to get the last star coin in 2-1 which sits just above the abyss, one player can just jump to their death for it and as long as another player lives you've collected the coin. However you need not sacrifice your life to do this: you can press down and 'a' to force yourself into a bubble saving yourself from death. This is true in general as long as you have enough time to see your death coming. This is also useful if one player runs ahead to the right. The screen will expand a bit but then it will just move to the right following the player in the lead. Players left behind walls or now forced into lava pits will die unless they use the bubble.

Misc.

• If all players hit the ground at the same time from a ground pound it acts like hitting a pow block, killing the enemies on the screen.
• If you hold a player who has a projectile power over your head they can still use their power.
• Bubbles can be popped by hitting them with your fire or ice projectiles as well as thrown shells or blocks.
• All players get the extra lives from anyone collecting 100 coins or finishing a level with more than 7 enemies on the screen.

PowerShell Scanning Script

I've hooked up the printer/scanner to the Media Center PC since I leave that on all the time anyway so we can have a networked printer. I wanted to hook up the scanner in a somewhat similar fashion but I didn't want to install HP's software (other than the drivers of course). So I've written my own script for scanning in PowerShell that does the following:

1. Scans using the Windows Image Acquisition APIs via COM
2. Runs OCR on the image using Microsoft Office Document Imaging via COM (which may already be on your PC if you have Office installed)
3. Converts the image to JPEG using .NET Image APIs
4. Stores the OCR text into the EXIF comment field using .NET Image APIs (which means Windows Search can index the image by the text in the image)
5. Moves the image to the public share

Here's the actual code from my scan.ps1 file:

param([Switch] $ShowProgress, [switch] $OpenCompletedResult)

$filePathTemplate = "C:\users\public\pictures\scanned\scan {0} {1}.{2}";
$time = get-date -uformat "%Y-%m-%d";

[void]([reflection.assembly]::loadfile( "C:\Windows\Microsoft.NET\Framework\v2.0.50727\System.Drawing.dll"))

$deviceManager = new-object -ComObject WIA.DeviceManager
$device = $deviceManager.DeviceInfos.Item(1).Connect();

foreach ($item in $device.Items) {
        $fileIdx = 0;
        while (test-path ($filePathTemplate -f $time,$fileIdx,"*")) {
                [void](++$fileIdx);
        }

        if ($ShowProgress) { "Scanning..." }

        $image = $item.Transfer();
        $fileName = ($filePathTemplate -f $time,$fileIdx,$image.FileExtension);
        $image.SaveFile($fileName);
        clear-variable image

        if ($ShowProgress) { "Running OCR..." }

        $modiDocument = new-object -comobject modi.document;
        $modiDocument.Create($fileName);
        $modiDocument.OCR();
        if ($modiDocument.Images.Count -gt 0) {
                $ocrText = $modiDocument.Images.Item(0).Layout.Text.ToString().Trim();
                $modiDocument.Close();
                clear-variable modiDocument

                if (!($ocrText.Equals(""))) {
                        $fileAsImage = New-Object -TypeName system.drawing.bitmap -ArgumentList $fileName
                        if (!($fileName.EndsWith(".jpg") -or $fileName.EndsWith(".jpeg"))) {
                                if ($ShowProgress) { "Converting to JPEG..." }

                                $newFileName = ($filePathTemplate -f $time,$fileIdx,"jpg");
                                $fileAsImage.Save($newFileName, [System.Drawing.Imaging.ImageFormat]::Jpeg);
                                $fileAsImage.Dispose();
                                del $fileName;

                                $fileAsImage = New-Object -TypeName system.drawing.bitmap -ArgumentList $newFileName 
                                $fileName = $newFileName
                        }

                        if ($ShowProgress) { "Saving OCR Text..." }

                        $property = $fileAsImage.PropertyItems[0];
                        $property.Id = 40092;
                        $property.Type = 1;
                        $property.Value = [system.text.encoding]::Unicode.GetBytes($ocrText);
                        $property.Len = $property.Value.Count;
                        $fileAsImage.SetPropertyItem($property);
                        $fileAsImage.Save(($fileName + ".new"));
                        $fileAsImage.Dispose();
                        del $fileName;
                        ren ($fileName + ".new") $fileName
                }
        }
        else {
                $modiDocument.Close();
                clear-variable modiDocument
        }

        if ($ShowProgress) { "Done." }

        if ($OpenCompletedResult) {
                . $fileName;
        }
        else {
                $result = dir $fileName;
                $result | add-member -membertype noteproperty -name OCRText -value $ocrText
                $result
        }
}

I ran into a few issues:

• MODI doesn't seem to be in the Office 2010 Technical Preview I installed first. Installing Office 2007 fixed that.
• The MODI.Document class, at least via PowerShell, can't be instantiated in a 64bit environment. To run the script on my 64bit OS I had to start powershell from the 32bit cmd.exe (C:\windows\syswow64\cmd.exe).
• I was planning to hook up my script to the scanner's 'Scan' button, but HP didn't get the button working for their Vista driver. Their workaround is "don't do that!".
• You must call Image.Dispose() to get .NET to release its reference to the corresponding image file.
• In trying to figure out how to store the text in the files comment, I ran into a dead-end trying to find the corresponding setter for GetDetailsOf which folks like James O'Neil use in PowerShell for interesting ends.

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