Category Archives: windows

verifying an md5 or sha-256 file hash with just PowerShell

Tools
You see this possibility for a lot of software downloads but if you’re like me you hardly ever end up doing it: verifying an installation file’s MD5 or SHA-something hash.
For Open Source software this is however recommended if you aren’t downloaded from the official mirror (and even then) and certainly if it’s anything related to security (like Keepass for example).

But to verify that MD5 hash you probably need to install yet another piece of software you’re hardly going to need, so you end up not bothering at all.

Hold on a second.

If you have a recent Windows system with PowerShell installed, you probably have all you need to verify that MD5 hash.

Try this in the PowerShell command prompt:

Get-FileHash .\KeePass-2.30-Setup.exe -Algorithm md5

It should print out something like this:

Algorithm       Hash
---------       ----
MD5             CD430EB0F108BB192D2155C68EB7BB48

Which happens to be exactly the MD5 hash code listed on the site for that version of the Keepass installer. Yay!
Without that -Algorithm parameter it prints out the SHA-256 hash by default, but that’s longer and harder to compare visually even though it’s more precise. You can also specify other types of hashes like SHA1, SHA512, MACTripleDES and RIPEMD160.

That was easy and required no additional software.
Pretty damn sweet.

Photo by Julien Dumont, cc-licensed.

how to move an unreachable window on windows 7, 8 or 10

arrowsOn the “good” old XP this required some trickery and knowledge of window specific shortcuts, but on more recent version of Windows this has become really easy to do.

So if you run into a situation where an application’s window is outside your visible area, because you disconnected a second screen for example and the app doesn’t automatically snap to the only screen left, simply do this:

  • Keep the Windows key pressed and hit the cursor key left or right.

Your window will simply snap back to your current screen and all is well.
Using it with the up & down arrow will maximize or minimize the active window. Always handy to know those shortcuts if you have both hands on the keyboard anyway.

If this doesn’t work because the window cannot be resized, you can also try this, but it’s a bit more tricky:

  • Activate the application by clicking it in the taskbar.
  • Hold the Alt key, and press the space bar.
    A context menu will pop up now, where the first option is to move the window.
  • Navigate down 1 entry by using pressing the down cursor-key once.
  • Hit Enter.
  • Now you can move the Window with the cursor keys left, right, up & down.
    As soon as you use a cursor key to move the window, your mouse locks on to it as well. So you can now use the mouse as well to move it back into visual range.

If this doesn’t seem to work straight away, try it out on an application like Notepad first, so you get the hang of it.

Photo by Dean Hochman, cc-licensed.

find and delete duplicate files with just Powershell

... analog computer!

Consider this. You have the same files with different file names spread out over a bunch of folders. If you are on a recent Windows machine, Powershell is all you need to get out of that mess and delete the duplicates.
This also means you get to do this from the command line which makes it extra l33t.

Cool. Let’s get started.

ls *.* -recurse | get-filehash | group -property hash | where { $_.count -gt 1 } 
| % { $_.group | select -skip 1 } | del

Bam!
You’re done.

Alright. Here’s what going on in detail:

ls *.* -recurse             # get all files in the current folder and all subfolders
get-filehash                # calculate the file hash for all files
group -property hash        # group them by the hash value
where { $_.count -gt 1 }    # select those groups with more than 1 item
% {                         # for all groups
    $_.group |              # output the group content, which are the files
    select -skip 1          # select all but the first file 
   }                        # (we don't want to delete all of them right?)
del                         # delete the file

If you want to experiment with this I’d recommend you to change the last del command with something safer, like echo which just prints out the file or by adding the -WhatIf parameter so simulate a delete.

Oh yeah, **DISCLAIMER**. Don’t just randomly copy past Powershell code and execute it on your machine if you don’t know what you are doing. Certainly if it’s deleting files like the example above. You might end up deleting more than you bargained for.  :)

Photo by James Vaughan, cc-licensed.

how to get code from tfs from the command line

Green blurry command line shots are so cyber.

Ever wanted to pull an update from the TFS server for all workspaces you have without having to start up the Visual Studio? Well I did. Visual Studio is rather slow in starting up and then you have to navigate to the TFS explorer (clicky clicky) and manually update the workspaces (clicky clicky) and then wait till the whole thing is done and VS becomes responsive again (waity waity).

You have the tf.exe command which you can use from a command prompt, but that requires you to use the VS command line because the right paths are set there. You could set the paths so they are available in all your shells, but that’s not very handy either.

I just wanted a batch script that I could run from any shell, that would just update my workspaces for me. Nice and easy.
Like when I press CTRL-R in Windows (Run) and type getfoo.cmd<enter>, it just makes it all happen for me.

So here’s how I did that:

@echo off

cls

:: Importing VS 2012 command line variables so we can run TF.exe
if exist "C:\Program Files (x86)\Microsoft Visual Studio 11.0\Common7\Tools\VsDevCmd.bat" (
echo Importing VS 2012 environment variables...
setlocal
call "C:\Program Files (x86)\Microsoft Visual Studio 11.0\Common7\Tools\VsDevCmd.bat"
)

echo.
echo *** Updating TFS workspaces ***
echo.

:: Repeat this for all workspaces you want to update.
d:
cd D:\WS\pathtosolutionfiles\

tf get . /version:T /recursive

echo.
echo *** Workspace updated. ***
echo.