Detecting 64bit vs. 32bit Linux

[Lawrence D'Oliveiro]

In article <mailman.7974.1152537684.27775.python-list at python.org>,
 Robin Becker <robin at reportlab.com> wrote:

>Michael Yanowitz wrote:
>......
>> 
>>> I need to detect whether the operating system I am running on (not the 
>>> Python version) is 64bit or 32bit. One requirement is that I need to 
>>> include support for non-Intel/AMD architectures.
>> 
>> The standard C way would be to check sizeof(void *).
>so on those old ARM RISC OSes with 32 bit arithmetic would I get sizeof(void 
>*) 
>== 4 when the address bus was 26 bits wide?

And the original 68000-based Macs where you would get the same 
sizeof(void *), but the address bus was only 24 bits wide. Nevertheless, 
you were supposed to pretend that addresses were a full 32 bits in size. 
The programs that didn't got into trouble later.