Create a Custom Detection Script for Cygwin (PowerShell)

Microsoft Endpoint Manager Configuration Manager (MEMCM / SCCM) and Microsoft Intune use Detection Rules to determine the presence of Applications & Win32 Apps. The detection rules ensure that application installations only begin to run if the application is not already installed on the device. This article will serve as an informative guide and give you a clear understanding of how to create an updated custom detection script for each new version of the Cygwin using PowerShell.

How to Create a Custom Detection Script for Cygwin

Cygwin (File Detection Method)

• Install the version of Cygwin you want to deploy on a test box or VM
  • Check out the following posts for further details
    • Cygwin Silent Install (How-To Guide)
    • Cygwin Install and Uninstall (PowerShell)
• Open Windows PowerShell ISE by Right-Clicking on Windows PowerShell ISE and selecting Run as Administrator
• Copy the following code into the Windows PowerShell ISE

## Check for Cygwin (File Detection Method)
$CygwinExe = (Get-ChildItem -Path "C:\cygwin\bin\cygwin1.dll","C:\cygwin64\bin\cygwin1.dll" -ErrorAction SilentlyContinue)
$CygwinExe.FullName
$CygwinPath = $($CygwinExe.FullName).Replace("C:\","")
$FileVersion = (Get-Item -Path "$($CygwinExe.FullName)" -ErrorAction SilentlyContinue).VersionInfo.FileVersion

## Create Text File with Cygwin File Detection Method
$FilePath = "C:\Windows\Temp\Cygwin_Detection_Method.txt"
New-Item -Path "$FilePath" -Force
Set-Content -Path "$FilePath" -Value "If([String](Get-Item -Path `"`$Env:HomeDrive\$CygwinPath`" -ErrorAction SilentlyContinue).VersionInfo.FileVersion -ge `"$FileVersion`"){"
Add-Content -Path "$FilePath" -Value "Write-Host `"Installed`""
Add-Content -Path "$FilePath" -Value "Exit 0"
Add-Content -Path "$FilePath" -Value "}"
Add-Content -Path "$FilePath" -Value "else {"
Add-Content -Path "$FilePath" -Value "Exit 1"
Add-Content -Path "$FilePath" -Value "}"
Invoke-Item $FilePath

• Click Run Script (F5)
• A text file will open with the Cygwin Detection Method script required to detect the current version of Cygwin that is installed on the device you are running the script from.

Example:

If([String](Get-Item -Path "$Env:HomeDrive\cygwin64\bin\cygwin1.dll" -ErrorAction SilentlyContinue).VersionInfo.FileVersion -ge "3.3.5"){
Write-Host "Installed"
Exit 0
}
else {
Exit 1
}

• Copy the Cygwin Detection Method script content into the Custom Detection Rules (Script)
• Microsoft Endpoint Manager Configuration Manager (MEMCM / SCCM)
  • https://docs.microsoft.com/en-us/mem/configmgr/apps/deploy-use/create-applications#bkmk_detect-script
• Microsoft Intune
  • https://docs.microsoft.com/en-us/mem/intune/apps/apps-win32-add

Always make sure to test everything in a development environment prior to implementing anything into production. The information in this article is provided “As Is” without warranty of any kind.