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Hi Team

I just came across this script in tech gallery and wanted to understand one specific thing

https://gallery.technet.microsoft.com/scriptcenter/Windows-Service-Compare-51eeb1ec#content

if (!(Test-Path .$XmlNameBefore)) {
Write-Host "(BEFORE)" -ForegroundColor Green -NoNewline
Write-Host " Connecting to $Computer..." -NoNewline

        try {
            get-wmiobject win32_service -ComputerName $Computer -ErrorAction Ignore | select SystemName,Name,DisplayName,State,StartMode | sort StartMode | Export-Clixml .\$XmlNameBefore
                if ($?) {Write-Host "Success" -ForegroundColor Green}
                else {
                    Write-Host "WMI connection failed" -ForegroundColor Red 
                    Remove-Item .\$XmlNameBefore -recurse
                    }

I understand most of the code but except 1 thing.

if ($?) {Write-Host "Success" -ForegroundColor Green}

What is "$?" here referring to in the above if statement?
can some one please help me understand this "$?"

@Vj-Sriram ,

$? is one of the automatic variables in PowerShell. They store state information and are created and maintained by PowerShell. There are several of them and can be very useful. You've probably used $_, which represents the current pipeline object, or $HOME which contains the full path of the user's home directory.

$? contains the success / failure status of the last command that was executed. It will be either True or False

So in this script, the previous command is
get-wmiobject win32_service -ComputerName $Computer -ErrorAction Ignore | select SystemName,Name,DisplayName,State,StartMode | sort StartMode | Export-Clixml .\$XmlNameBefore

If this command is successful, $? will contain True, and will write "Success" to the host, if the command fails, $? will contain False and write "WMI connection failed" to the host.

For more information about automatic variables, check out About Automatic Variables

Hi Mike

Thank you for the explanation