Get-CMInstallPath.psm1

#region Get-CMInstallPath
function Get-CMInstallPath {
    function Split-CommandLine {
        [CmdletBinding()]
        Param
        (
            [Parameter(Mandatory = $false, ValueFromPipeline = $true, ValueFromPipelineByPropertyName = $true, Position = 0)]
            [ValidateNotNullOrEmpty()]
            [string]$CommandLine
        )

        Begin {
            $Kernel32Definition = @'
        [DllImport("kernel32")]
        public static extern IntPtr GetCommandLineW();
        [DllImport("kernel32")]
        public static extern IntPtr LocalFree(IntPtr hMem);
'@
            $Kernel32 = Add-Type -MemberDefinition $Kernel32Definition -Name 'Kernel32' -Namespace 'Win32' -PassThru

            $Shell32Definition = @'
        [DllImport("shell32.dll", SetLastError = true)]
        public static extern IntPtr CommandLineToArgvW(
            [MarshalAs(UnmanagedType.LPWStr)] string lpCmdLine,
            out int pNumArgs);
'@
            $Shell32 = Add-Type -MemberDefinition $Shell32Definition -Name 'Shell32' -Namespace 'Win32' -PassThru

            if (!$CommandLine) {
                $CommandLine = [System.Runtime.InteropServices.Marshal]::PtrToStringUni($Kernel32::GetCommandLineW())
            }
        }

        Process {
            $ParsedArgCount = 0
            $ParsedArgsPtr = $Shell32::CommandLineToArgvW($CommandLine, [ref]$ParsedArgCount)

            Try {
                $ParsedArgs = @();

                0..$ParsedArgCount | ForEach-Object {
                    $ParsedArgs += [System.Runtime.InteropServices.Marshal]::PtrToStringUni(
                        [System.Runtime.InteropServices.Marshal]::ReadIntPtr($ParsedArgsPtr, $_ * [IntPtr]::Size)
                    )
                }
            }
            Finally {
                $Kernel32::LocalFree($ParsedArgsPtr) | Out-Null
            }

            $ret = @()

            # -lt to skip the last item, which is a NULL ptr
            for ($i = 0; $i -lt $ParsedArgCount; $i += 1) {
                $ret += $ParsedArgs[$i]
            }

            return $ret
        }
    }
    $ServicePathName = Get-CimInstance -ClassName Win32_Service -Namespace root/CIMV2 -Filter "Name='CcmExec'" | Select-Object -ExpandProperty PathName
    $ServicePathName | Split-CommandLine | Split-Path -Parent
}
#endregion Get-CMInstallPath