Windows x64 vs x86：硬件 vs. 操作系统 vs. 进程

Question

I'm having trouble with things breaking based on x86 vs x64 in Python 3 on Windows.

I need to know if my Python program is running:

• On x64 vs. x86 Hardware
• On a x64 vs. x86 Operating System
• In a x64 vs. x86 Process

They are not the same thing (at all!).

AMD64 architecture processors can run either 64 or 32 bit operating systems .

And 64 bit operating systems can run either 64 or 32 bit processes .

I know that:

• Python's platform.architecture() returns a string - but which of those 3 does it represent? (The documentation doesn't seem to say.)
• If (sys.maxsize > 2**32) then I'm in a 64 bit process. Fine; but if I'm in 32 bit process how can I tell if I'm on a 64 or 32 bit OS?

To forestall the inevitable "why do you care?" questions, it's because my Python program is automating configuration of Windows - things are in different places on x86 vs x64 Windows, but I don't know in advance if my program will be running on 32 or 64 bit Python.

So I need to figure that out.

Answer 1

So your actual question is whether the Windows you're running on is x64? :)

Riffing off this and this , how about

import os
arch = (
    os.environ.get("PROCESSOR_ARCHITEW6432") or 
    os.environ.get("PROCESSOR_ARCHITECTURE")
)
# `arch` should now reliably be `x64` if the system is 64-bit.

Answer 2

I believe this will work, but I haven't tested it on a 32-bit version of Windows:

import sys, os
x64_process = (sys.maxsize > 2**32)
x64_os = os.environ.get('ProgramW6432') is not None

And probably my most important use case - restarting explorer.exe after registry changes:

def restartExplorer():
    '''Restart explorer'''
    do(r'taskkill /f /im explorer.exe')
    if x64_os and not x64_process:
        do(os.environ['systemroot']+ r'\sysnative\cmd.exe /c start /B explorer.exe') # because this Python is in a 32 bit process
    else:
        do("start explorer.exe")

I won't give you the implementation of do() because it's pretty obvious. (But will if somebody asks.)