From: Walton Hoops <walton@...>
Date: 2010-01-16T05:20:58+09:00
Subject: Re: How to know the OS architecture (32 or 64 bits)?

On 1/15/2010 1:07 PM, Phillip Gawlowski wrote:
> On 15.01.2010 20:56, Walton Hoops wrote:
>
>> My main concern with that though:
>> Would RbConfig::CONFIG['host_cpu'] return "x86_64" if I'm running 32-bit
>> Linux on a 64-bit CPU?
>
> No. If the OS isn't 64 bits itself, it'll run on an x86_64 
> architecture, but the CPU is in 32 bit mode. The only thing you can 
> really test, is the bit-ness of the OS, not the CPU.
>
> After all, how should a 32 bit OS deal with a 64 bit memory address?
>
> -- 
> Phillip Gawlowski
>
Makes sense, but I don't know enough about low-level OS/hardware to be 
sure that there isn't a CPU flag exposed that would still allow for an 
app or the OS to determine the bittedness of the CPU.  So I asked and 
was answered :-)