Check if 32 or 64-bit Windows OS via registry [duplicate]

Possible Duplicate:
Detect Windows Server version 32/64-bit in CLI

Is there a way to check whether a user is running a 64-bit or 32-bit operating system by looking in the registry?

The following site makes some suggestions: http://www.maxi-pedia.com/32+Bit+or+64+Bit+Operating+System

But the suggestions of

HKLM\HARDWARE\DESCRIPTION\System\CentralProcessor\0

and

HKLM\SYSTEM\CurrentCongtrolSet\Control\Session Manager\Envirornment

do not appear to exist in my registry

The registry key

HKLM\SOFTWARE\Microsoft\Windows NT\CurrentVersion\BuildLabEx

should give you the required info