Python: What OS am I running on?

Question

What do I need to look at to see whether I\'m on Windows or Unix, etc?

Answer 1

This solution works for both python and jython.

module os_identify.py:

import platform
import os

# This module contains functions to determine the basic type of
# OS we are running on.
# Contrary to the functions in the `os` and `platform` modules,
# these allow to identify the actual basic OS,
# no matter whether running on the `python` or `jython` interpreter.

def is_linux():
    try:
        platform.linux_distribution()
        return True
    except:
        return False

def is_windows():
    try:
        platform.win32_ver()
        return True
    except:
        return False

def is_mac():
    try:
        platform.mac_ver()
        return True
    except:
        return False

def name():
    if is_linux():
        return "Linux"
    elif is_windows():
        return "Windows"
    elif is_mac():
        return "Mac"
    else:
        return "<unknown>" 

Use like this:

import os_identify

print "My OS: " + os_identify.name()

Answer 2

For the record here's the results on Mac:

>>> import os
>>> os.name
'posix'
>>> import platform
>>> platform.system()
'Darwin'
>>> platform.release()
'8.11.1'

Answer 3

You can also use sys.platform if you already have imported sys and you don't want to import another module

>>> import sys
>>> sys.platform
'linux2'

Answer 4

Short Story

Use platform.system(). It returns Windows, Linux or Darwin (for OSX).

Long Story

There are 3 ways to get OS in Python, each with its own pro and cons:

Method 1

>>> import sys
>>> sys.platform
'win32'  # could be 'linux', 'linux2, 'darwin', 'freebsd8' etc

How this works (source): Internally it calls OS APIs to get name of the OS as defined by OS. See here for various OS-specific values.

Pro: No magic, low level.

Con: OS version dependent, so best not to use directly.

Method 2

>>> import os
>>> os.name
'nt'  # for Linux and Mac it prints 'posix'

How this works (source): Internally it checks if python has OS-specific modules called posix or nt.

Pro: Simple to check if posix OS

Con: no differentiation between Linux or OSX.

Method 3

>>> import platform
>>> platform.system()
'Windows' # for Linux it prints 'Linux', Mac it prints `'Darwin'

How this works (source): Internally it will eventually call internal OS APIs, get OS version-specific name like 'win32' or 'win16' or 'linux1' and then normalize to more generic names like 'Windows' or 'Linux' or 'Darwin' by applying several heuristics.

Pro: Best portable way for Windows, OSX and Linux.

Con: Python folks must keep normalization heuristic up to date.

Summary

• If you want to check if OS is Windows or Linux or OSX then the most reliable way is platform.system().
• If you want to make OS-specific calls but via built-in Python modules posix or nt then use os.name.
• If you want to get raw OS name as supplied by OS itself then use sys.platform.

Answer 5

How about a simple Enum implementation like the following? No need for external libs!

import platform
from enum import Enum
class OS(Enum):
    def checkPlatform(osName):
        return osName.lower()== platform.system().lower()

    MAC = checkPlatform("darwin")
    LINUX = checkPlatform("linux")
    WINDOWS = checkPlatform("windows")  #I haven't test this one

Simply you can access with Enum value

if OS.LINUX.value:
    print("Cool it is Linux")

P.S It is python3

Answer 6

I started a bit more systematic listing of what values you can expect using the various modules (feel free to edit and add your system):

Linux (64bit) + WSL

os.name                     posix
sys.platform                linux
platform.system()           Linux
sysconfig.get_platform()    linux-x86_64
platform.machine()          x86_64
platform.architecture()     ('64bit', '')

• tried with archlinux and mint, got same results
• on python2 sys.platform is suffixed by kernel version, e.g. linux2, everything else stays identical
• same output on Windows Subsystem for Linux (tried with ubuntu 18.04 LTS), except platform.architecture() = ('64bit', 'ELF')

WINDOWS (64bit)

(with 32bit column running in the 32bit subsystem)

official python installer   64bit                     32bit
-------------------------   -----                     -----
os.name                     nt                        nt
sys.platform                win32                     win32
platform.system()           Windows                   Windows
sysconfig.get_platform()    win-amd64                 win32
platform.machine()          AMD64                     AMD64
platform.architecture()     ('64bit', 'WindowsPE')    ('64bit', 'WindowsPE')

msys2                       64bit                     32bit
-----                       -----                     -----
os.name                     posix                     posix
sys.platform                msys                      msys
platform.system()           MSYS_NT-10.0              MSYS_NT-10.0-WOW
sysconfig.get_platform()    msys-2.11.2-x86_64        msys-2.11.2-i686
platform.machine()          x86_64                    i686
platform.architecture()     ('64bit', 'WindowsPE')    ('32bit', 'WindowsPE')

msys2                       mingw-w64-x86_64-python3  mingw-w64-i686-python3
-----                       ------------------------  ----------------------
os.name                     nt                        nt
sys.platform                win32                     win32
platform.system()           Windows                   Windows
sysconfig.get_platform()    mingw                     mingw
platform.machine()          AMD64                     AMD64
platform.architecture()     ('64bit', 'WindowsPE')    ('32bit', 'WindowsPE')

cygwin                      64bit                     32bit
------                      -----                     -----
os.name                     posix                     posix
sys.platform                cygwin                    cygwin
platform.system()           CYGWIN_NT-10.0            CYGWIN_NT-10.0-WOW
sysconfig.get_platform()    cygwin-3.0.1-x86_64       cygwin-3.0.1-i686
platform.machine()          x86_64                    i686
platform.architecture()     ('64bit', 'WindowsPE')    ('32bit', 'WindowsPE')

Some remarks:

• there is also distutils.util.get_platform() which is identical to `sysconfig.get_platform
• anaconda on windows is same as official python windows installer
• I don't have a Mac nor a true 32bit system and was not motivated to do it online

To compare with your system, simply run this script (and please append results here if missing :)

from __future__ import print_function
import os
import sys
import platform
import sysconfig

print("os.name                      ",  os.name)
print("sys.platform                 ",  sys.platform)
print("platform.system()            ",  platform.system())
print("sysconfig.get_platform()     ",  sysconfig.get_platform())
print("platform.machine()           ",  platform.machine())
print("platform.architecture()      ",  platform.architecture())