Question

This could be a simple question, but I couldn’t find a proper answer.

How do you update the environment variables from within a current Windows PowerShell session without closing the current one?

Up to now, when I modify for example the PATH environment variable from Control Panel > System, I have to close current session and open a new one, so that variables are refreshed, or issue a SetEnviromentVariable which is cumbersome.

I’m coming from the Linux world, so I’m looking for something like source command.

Answer 1

The environment gets populated on process start-up which is why you’ll need to restart the process.

You can update the environment by reading it from the registry. Maybe with a script like the following:

function Update-Environment {
    $locations = 'HKLM:\SYSTEM\CurrentControlSet\Control\Session Manager\Environment',
                 'HKCU:\Environment'

    $locations | ForEach-Object {
        $k = Get-Item $_
        $k.GetValueNames() | ForEach-Object {
            $name  = $_
            $value = $k.GetValue($_)

            if ($userLocation -and $name -ieq 'PATH') {
                Env:\Path += ";$value"
            } else {
                Set-Item -Path Env:\$name -Value $value
            }
        }

        $userLocation = $true
    }
}

(untested)