Is this PowerShell Session a 32-bit or a 64-bit?

How can one identify whether the current PowerShell process is running the 32-bit version (x86) or the 64-bit version of PowerShell? Well first, why would you care? You are right, normally I do not care, but if I need to execute VBscript with Invoke-Script, I need to know as that only works on 32-bit Windows.

I'm now running Vista x64 - and that is actually a pleasure. For the first time, I feel my PC is responsive enough when running many applications. If you are interested, my PC is a Dell D830 with 4 GB RAM and a Intel Turbo Channel module having 1 GB. OK specs and nice performance.

One of the minor problems I have encountered is that MSScriptControl.ScriptControl used by Invoke-Script cannot be started from 64-bit PowerShell. I simply does not exist :(

So I set off hunting a way of finding out how to differentiate, so I could do something clever.

First, I looked at the $host variable, but that seemed to return the same info. Next, I looked at the current process. The only difference I found was the image path, there does not seem to be any flag indicating the execution mode. Strange, I would have expected that.

Before jumping on a image path test, I looked as wmi32_process as well. This did not really help me, but at least win32_operatingSystem.OSArchitecture help me figuring out the platform.

This all added up in Get-Architecture.ps1 which contains -

param([switch]$CurrentProcess)

if ($CurrentProcess.ispresent) {
    $me=[diagnostics.process]::GetCurrentProcess()
    if ($me.path -match '\\syswow64\\') {
        32
    }
    else {
        64
    }
}
else {
    $os=Get-WMIObject win32_operatingsystem
    if ($os.OSArchitecture -eq "64-bit") {
        64
    }
    else {
        32
    }
}

Example -

PS> powershell -noprofile {get-architecture -currentprocess}
64
PS> C:\WINDOWS\syswow64\windowspowershell\v1.0\powershell.exe -noprofile {get-architecture -currentprocess}
32
PS>  powershell -noprofile {get-architecture}
64
PS> C:\WINDOWS\syswow64\windowspowershell\v1.0\powershell.exe -noprofile {get-architecture}
64
PS> powershell -noprofile {get-architecture -currentprocess}
64
PS> C:\WINDOWS\syswow64\windowspowershell\v1.0\powershell.exe -noprofile {get-architecture -currentprocess}
32

Suggestions for improvements are highly welcome!