#!/usr/bin/env python3

""" This module tries to retrieve as much platform-identifying data as
 possible. It makes this information available via function APIs.

 If called from the command line, it prints the platform
 information concatenated as single string to stdout. The output
 format is useable as part of a filename.

"""
# This module is maintained by Marc-Andre Lemburg <mal@egenix.com>.
# If you find problems, please submit bug reports/patches via the
# Python bug tracker (http://bugs.python.org) and assign them to "lemburg".
#
# Still needed:
# * support for MS-DOS (PythonDX ?)
# * support for Amiga and other still unsupported platforms running Python
# * support for additional Linux distributions
#
# Many thanks to all those who helped adding platform-specific
# checks (in no particular order):
#
# Charles G Waldman, David Arnold, Gordon McMillan, Ben Darnell,
# Jeff Bauer, Cliff Crawford, Ivan Van Laningham, Josef
# Betancourt, Randall Hopper, Karl Putland, John Farrell, Greg
# Andruk, Just van Rossum, Thomas Heller, Mark R. Levinson, Mark
# Hammond, Bill Tutt, Hans Nowak, Uwe Zessin (OpenVMS support),
# Colin Kong, Trent Mick, Guido van Rossum, Anthony Baxter, Steve
# Dower
#
# History:
#
# <see CVS and SVN checkin messages for history>
#
# 1.0.8 - changed Windows support to read version from kernel32.dll
# 1.0.7 - added DEV_NULL
# 1.0.6 - added linux_distribution()
# 1.0.5 - fixed Java support to allow running the module on Jython
# 1.0.4 - added IronPython support
# 1.0.3 - added normalization of Windows system name
# 1.0.2 - added more Windows support
# 1.0.1 - reformatted to make doc.py happy
# 1.0.0 - reformatted a bit and checked into Python CVS
# 0.8.0 - added sys.version parser and various new access
# APIs (python_version(), python_compiler(), etc.)
# 0.7.2 - fixed architecture() to use sizeof(pointer) where available
# 0.7.1 - added support for Caldera OpenLinux
# 0.7.0 - some fixes for WinCE; untabified the source file
# 0.6.2 - support for OpenVMS - requires version 1.5.2-V006 or higher and
# vms_lib.getsyi() configured
# 0.6.1 - added code to prevent 'uname -p' on platforms which are
# known not to support it
# 0.6.0 - fixed win32_ver() to hopefully work on Win95,98,NT and Win2k;
# did some cleanup of the interfaces - some APIs have changed
# 0.5.5 - fixed another type in the MacOS code... should have
# used more coffee today ;-)
# 0.5.4 - fixed a few typos in the MacOS code
# 0.5.3 - added experimental MacOS support; added better popen()
# workarounds in _syscmd_ver() -- still not 100% elegant
# though
# 0.5.2 - fixed uname() to return '' instead of 'unknown' in all
# return values (the system uname command tends to return
# 'unknown' instead of just leaving the field empty)
# 0.5.1 - included code for slackware dist; added exception handlers
# to cover up situations where platforms don't have os.popen
# (e.g. Mac) or fail on socket.gethostname(); fixed libc
# detection RE
# 0.5.0 - changed the API names referring to system commands to *syscmd*;
# added java_ver(); made syscmd_ver() a private
# API (was system_ver() in previous versions) -- use uname()
# instead; extended the win32_ver() to also return processor
# type information
# 0.4.0 - added win32_ver() and modified the platform() output for WinXX
# 0.3.4 - fixed a bug in _follow_symlinks()
# 0.3.3 - fixed popen() and "file" command invocation bugs
# 0.3.2 - added architecture() API and support for it in platform()
# 0.3.1 - fixed syscmd_ver() RE to support Windows NT
# 0.3.0 - added system alias support
# 0.2.3 - removed 'wince' again... oh well.
# 0.2.2 - added 'wince' to syscmd_ver() supported platforms
# 0.2.1 - added cache logic and changed the platform string format
# 0.2.0 - changed the API to use functions instead of module globals
# since some action take too long to be run on module import
# 0.1.0 - first release
#
# You can always get the latest version of this module at:
#
# http://www.egenix.com/files/python/platform.py
#
# If that URL should fail, try contacting the author.

__copyright__ = """
 Copyright (c) 1999-2000, Marc-Andre Lemburg; mailto:mal@lemburg.com
 Copyright (c) 2000-2010, eGenix.com Software GmbH; mailto:info@egenix.com

 Permission to use, copy, modify, and distribute this software and its
 documentation for any purpose and without fee or royalty is hereby granted,
 provided that the above copyright notice appear in all copies and that
 both that copyright notice and this permission notice appear in
 supporting documentation or portions thereof, including modifications,
 that you make.

 EGENIX.COM SOFTWARE GMBH DISCLAIMS ALL WARRANTIES WITH REGARD TO
 THIS SOFTWARE, INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY AND
 FITNESS, IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY SPECIAL,
 INDIRECT OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING
 FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN ACTION OF CONTRACT,
 NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION
 WITH THE USE OR PERFORMANCE OF THIS SOFTWARE !

"""

__version__ = '1.0.8'

import collections
import os
import re
import sys

### Globals & Constants

# Helper for comparing two version number strings.
# Based on the description of the PHP's version_compare():
# http://php.net/manual/en/function.version-compare.php

_ver_stages = {
 # any string not found in this dict, will get 0 assigned
 'dev': 10,
 'alpha': 20, 'a': 20,
 'beta': 30, 'b': 30,
 'c': 40,
 'RC': 50, 'rc': 50,
 # number, will get 100 assigned
 'pl': 200, 'p': 200,
}

_component_re = re.compile(r'([0-9]+|[._+-])')

def _comparable_version(version):
 result = []
 for v in _component_re.split(version):
 if v not in '._+-':
 try:
 v = int(v, 10)
 t = 100
 except ValueError:
 t = _ver_stages.get(v, 0)
 result.extend((t, v))
 return result

### Platform specific APIs

_libc_search = re.compile(b'(__libc_init)'
 b'|'
 b'(GLIBC_([0-9.]+))'
 b'|'
 br'(libc(_\w+)?\.so(?:\.(\d[0-9.]*))?)', re.ASCII)

def libc_ver(executable=None, lib='', version='', chunksize=16384):

 """ Tries to determine the libc version that the file executable
 (which defaults to the Python interpreter) is linked against.

 Returns a tuple of strings (lib,version) which default to the
 given parameters in case the lookup fails.

 Note that the function has intimate knowledge of how different
 libc versions add symbols to the executable and thus is probably
 only useable for executables compiled using gcc.

 The file is read and scanned in chunks of chunksize bytes.

 """
 if executable is None:
 try:
 ver = os.confstr('CS_GNU_LIBC_VERSION')
 # parse 'glibc 2.28' as ('glibc', '2.28')
 parts = ver.split(maxsplit=1)
 if len(parts) == 2:
 return tuple(parts)
 except (AttributeError, ValueError, OSError):
 # os.confstr() or CS_GNU_LIBC_VERSION value not available
 pass

 executable = sys.executable

 V = _comparable_version
 if hasattr(os.path, 'realpath'):
 # Python 2.2 introduced os.path.realpath(); it is used
 # here to work around problems with Cygwin not being
 # able to open symlinks for reading
 executable = os.path.realpath(executable)
 with open(executable, 'rb') as f:
 binary = f.read(chunksize)
 pos = 0
 while pos < len(binary):
 if b'libc' in binary or b'GLIBC' in binary:
 m = _libc_search.search(binary, pos)
 else:
 m = None
 if not m or m.end() == len(binary):
 chunk = f.read(chunksize)
 if chunk:
 binary = binary[max(pos, len(binary) - 1000):] + chunk
 pos = 0
 continue
 if not m:
 break
 libcinit, glibc, glibcversion, so, threads, soversion = [
 s.decode('latin1') if s is not None else s
 for s in m.groups()]
 if libcinit and not lib:
 lib = 'libc'
 elif glibc:
 if lib != 'glibc':
 lib = 'glibc'
 version = glibcversion
 elif V(glibcversion) > V(version):
 version = glibcversion
 elif so:
 if lib != 'glibc':
 lib = 'libc'
 if soversion and (not version or V(soversion) > V(version)):
 version = soversion
 if threads and version[-len(threads):] != threads:
 version = version + threads
 pos = m.end()
 return lib, version

def _norm_version(version, build=''):

 """ Normalize the version and build strings and return a single
 version string using the format major.minor.build (or patchlevel).
 """
 l = version.split('.')
 if build:
 l.append(build)
 try:
 ints = map(int, l)
 except ValueError:
 strings = l
 else:
 strings = list(map(str, ints))
 version = '.'.join(strings[:3])
 return version

_ver_output = re.compile(r'(?:([\w ]+) ([\w.]+) '
 r'.*'
 r'\[.* ([\d.]+)\])')

# Examples of VER command output:
#
# Windows 2000: Microsoft Windows 2000 [Version 5.00.2195]
# Windows XP: Microsoft Windows XP [Version 5.1.2600]
# Windows Vista: Microsoft Windows [Version 6.0.6002]
#
# Note that the "Version" string gets localized on different
# Windows versions.

def _syscmd_ver(system='', release='', version='',

 supported_platforms=('win32', 'win16', 'dos')):

 """ Tries to figure out the OS version used and returns
 a tuple (system, release, version).

 It uses the "ver" shell command for this which is known
 to exists on Windows, DOS. XXX Others too ?

 In case this fails, the given parameters are used as
 defaults.

 """
 if sys.platform not in supported_platforms:
 return system, release, version

 # Try some common cmd strings
 import subprocess
 for cmd in ('ver', 'command /c ver', 'cmd /c ver'):
 try:
 info = subprocess.check_output(cmd,
 stderr=subprocess.DEVNULL,
 text=True,
 shell=True)
 except (OSError, subprocess.CalledProcessError) as why:
 #print('Command %s failed: %s' % (cmd, why))
 continue
 else:
 break
 else:
 return system, release, version

 # Parse the output
 info = info.strip()
 m = _ver_output.match(info)
 if m is not None:
 system, release, version = m.groups()
 # Strip trailing dots from version and release
 if release[-1] == '.':
 release = release[:-1]
 if version[-1] == '.':
 version = version[:-1]
 # Normalize the version and build strings (eliminating additional
 # zeros)
 version = _norm_version(version)
 return system, release, version

_WIN32_CLIENT_RELEASES = {
 (5, 0): "2000",
 (5, 1): "XP",
 # Strictly, 5.2 client is XP 64-bit, but platform.py historically
 # has always called it 2003 Server
 (5, 2): "2003Server",
 (5, None): "post2003",

 (6, 0): "Vista",
 (6, 1): "7",
 (6, 2): "8",
 (6, 3): "8.1",
 (6, None): "post8.1",

 (10, 0): "10",
 (10, None): "post10",
}

# Server release name lookup will default to client names if necessary
_WIN32_SERVER_RELEASES = {
 (5, 2): "2003Server",

 (6, 0): "2008Server",
 (6, 1): "2008ServerR2",
 (6, 2): "2012Server",
 (6, 3): "2012ServerR2",
 (6, None): "post2012ServerR2",
}

def win32_is_iot():
 return win32_edition() in ('IoTUAP', 'NanoServer', 'WindowsCoreHeadless', 'IoTEdgeOS')

def win32_edition():
 try:
 try:
 import winreg
 except ImportError:
 import _winreg as winreg
 except ImportError:
 pass
 else:
 try:
 cvkey = r'SOFTWARE\Microsoft\Windows NT\CurrentVersion'
 with winreg.OpenKeyEx(winreg.HKEY_LOCAL_MACHINE, cvkey) as key:
 return winreg.QueryValueEx(key, 'EditionId')[0]
 except OSError:
 pass

 return None

def win32_ver(release='', version='', csd='', ptype=''):
 try:
 from sys import getwindowsversion
 except ImportError:
 return release, version, csd, ptype

 winver = getwindowsversion()
 maj, min, build = winver.platform_version or winver[:3]
 version = '{0}.{1}.{2}'.format(maj, min, build)

 release = (_WIN32_CLIENT_RELEASES.get((maj, min)) or
 _WIN32_CLIENT_RELEASES.get((maj, None)) or
 release)

 # getwindowsversion() reflect the compatibility mode Python is
 # running under, and so the service pack value is only going to be
 # valid if the versions match.
 if winver[:2] == (maj, min):
 try:
 csd = 'SP{}'.format(winver.service_pack_major)
 except AttributeError:
 if csd[:13] == 'Service Pack ':
 csd = 'SP' + csd[13:]

 # VER_NT_SERVER = 3
 if getattr(winver, 'product_type', None) == 3:
 release = (_WIN32_SERVER_RELEASES.get((maj, min)) or
 _WIN32_SERVER_RELEASES.get((maj, None)) or
 release)

 try:
 try:
 import winreg
 except ImportError:
 import _winreg as winreg
 except ImportError:
 pass
 else:
 try:
 cvkey = r'SOFTWARE\Microsoft\Windows NT\CurrentVersion'
 with winreg.OpenKeyEx(HKEY_LOCAL_MACHINE, cvkey) as key:
 ptype = QueryValueEx(key, 'CurrentType')[0]
 except:
 pass

 return release, version, csd, ptype


def _mac_ver_xml():
 fn = '/System/Library/CoreServices/SystemVersion.plist'
 if not os.path.exists(fn):
 return None

 try:
 import plistlib
 except ImportError:
 return None

 with open(fn, 'rb') as f:
 pl = plistlib.load(f)
 release = pl['ProductVersion']
 versioninfo = ('', '', '')
 machine = os.uname().machine
 if machine in ('ppc', 'Power Macintosh'):
 # Canonical name
 machine = 'PowerPC'

 return release, versioninfo, machine


def mac_ver(release='', versioninfo=('', '', ''), machine=''):

 """ Get macOS version information and return it as tuple (release,
 versioninfo, machine) with versioninfo being a tuple (version,
 dev_stage, non_release_version).

 Entries which cannot be determined are set to the parameter values
 which default to ''. All tuple entries are strings.
 """

 # First try reading the information from an XML file which should
 # always be present
 info = _mac_ver_xml()
 if info is not None:
 return info

 # If that also doesn't work return the default values
 return release, versioninfo, machine

def _java_getprop(name, default):

 from java.lang import System
 try:
 value = System.getProperty(name)
 if value is None:
 return default
 return value
 except AttributeError:
 return default

def java_ver(release='', vendor='', vminfo=('', '', ''), osinfo=('', '', '')):

 """ Version interface for Jython.

 Returns a tuple (release, vendor, vminfo, osinfo) with vminfo being
 a tuple (vm_name, vm_release, vm_vendor) and osinfo being a
 tuple (os_name, os_version, os_arch).

 Values which cannot be determined are set to the defaults
 given as parameters (which all default to '').

 """
 # Import the needed APIs
 try:
 import java.lang
 except ImportError:
 return release, vendor, vminfo, osinfo

 vendor = _java_getprop('java.vendor', vendor)
 release = _java_getprop('java.version', release)
 vm_name, vm_release, vm_vendor = vminfo
 vm_name = _java_getprop('java.vm.name', vm_name)
 vm_vendor = _java_getprop('java.vm.vendor', vm_vendor)
 vm_release = _java_getprop('java.vm.version', vm_release)
 vminfo = vm_name, vm_release, vm_vendor
 os_name, os_version, os_arch = osinfo
 os_arch = _java_getprop('java.os.arch', os_arch)
 os_name = _java_getprop('java.os.name', os_name)
 os_version = _java_getprop('java.os.version', os_version)
 osinfo = os_name, os_version, os_arch

 return release, vendor, vminfo, osinfo

### System name aliasing

def system_alias(system, release, version):

 """ Returns (system, release, version) aliased to common
 marketing names used for some systems.

 It also does some reordering of the information in some cases
 where it would otherwise cause confusion.

 """
 if system == 'SunOS':
 # Sun's OS
 if release < '5':
 # These releases use the old name SunOS
 return system, release, version
 # Modify release (marketing release = SunOS release - 3)
 l = release.split('.')
 if l:
 try:
 major = int(l[0])
 except ValueError:
 pass
 else:
 major = major - 3
 l[0] = str(major)
 release = '.'.join(l)
 if release < '6':
 system = 'Solaris'
 else:
 # XXX Whatever the new SunOS marketing name is...
 system = 'Solaris'

 elif system == 'IRIX64':
 # IRIX reports IRIX64 on platforms with 64-bit support; yet it
 # is really a version and not a different platform, since 32-bit
 # apps are also supported..
 system = 'IRIX'
 if version:
 version = version + ' (64bit)'
 else:
 version = '64bit'

 elif system in ('win32', 'win16'):
 # In case one of the other tricks
 system = 'Windows'

 # bpo-35516: Don't replace Darwin with macOS since input release and
 # version arguments can be different than the currently running version.

 return system, release, version

### Various internal helpers

def _platform(*args):

 """ Helper to format the platform string in a filename
 compatible format e.g. "system-version-machine".
 """
 # Format the platform string
 platform = '-'.join(x.strip() for x in filter(len, args))

 # Cleanup some possible filename obstacles...
 platform = platform.replace(' ', '_')
 platform = platform.replace('/', '-')
 platform = platform.replace('\\', '-')
 platform = platform.replace(':', '-')
 platform = platform.replace(';', '-')
 platform = platform.replace('"', '-')
 platform = platform.replace('(', '-')
 platform = platform.replace(')', '-')

 # No need to report 'unknown' information...
 platform = platform.replace('unknown', '')

 # Fold '--'s and remove trailing '-'
 while 1:
 cleaned = platform.replace('--', '-')
 if cleaned == platform:
 break
 platform = cleaned
 while platform[-1] == '-':
 platform = platform[:-1]

 return platform

def _node(default=''):

 """ Helper to determine the node name of this machine.
 """
 try:
 import socket
 except ImportError:
 # No sockets...
 return default
 try:
 return socket.gethostname()
 except OSError:
 # Still not working...
 return default

def _follow_symlinks(filepath):

 """ In case filepath is a symlink, follow it until a
 real file is reached.
 """
 filepath = os.path.abspath(filepath)
 while os.path.islink(filepath):
 filepath = os.path.normpath(
 os.path.join(os.path.dirname(filepath), os.readlink(filepath)))
 return filepath

def _syscmd_uname(option, default=''):

 """ Interface to the system's uname command.
 """
 if sys.platform in ('dos', 'win32', 'win16'):
 # XXX Others too ?
 return default

 import subprocess
 try:
 output = subprocess.check_output(('uname', option),
 stderr=subprocess.DEVNULL,
 text=True)
 except (OSError, subprocess.CalledProcessError):
 return default
 return (output.strip() or default)

def _syscmd_file(target, default=''):

 """ Interface to the system's file command.

 The function uses the -b option of the file command to have it
 omit the filename in its output. Follow the symlinks. It returns
 default in case the command should fail.

 """
 if sys.platform in ('dos', 'win32', 'win16'):
 # XXX Others too ?
 return default

 import subprocess
 target = _follow_symlinks(target)
 # "file" output is locale dependent: force the usage of the C locale
 # to get deterministic behavior.
 env = dict(os.environ, LC_ALL='C')
 try:
 # -b: do not prepend filenames to output lines (brief mode)
 output = subprocess.check_output(['file', '-b', target],
 stderr=subprocess.DEVNULL,
 env=env)
 except (OSError, subprocess.CalledProcessError):
 return default
 if not output:
 return default
 # With the C locale, the output should be mostly ASCII-compatible.
 # Decode from Latin-1 to prevent Unicode decode error.
 return output.decode('latin-1')

### Information about the used architecture

# Default values for architecture; non-empty strings override the
# defaults given as parameters
_default_architecture = {
 'win32': ('', 'WindowsPE'),
 'win16': ('', 'Windows'),
 'dos': ('', 'MSDOS'),
}

def architecture(executable=sys.executable, bits='', linkage=''):

 """ Queries the given executable (defaults to the Python interpreter
 binary) for various architecture information.

 Returns a tuple (bits, linkage) which contains information about
 the bit architecture and the linkage format used for the
 executable. Both values are returned as strings.

 Values that cannot be determined are returned as given by the
 parameter presets. If bits is given as '', the sizeof(pointer)
 (or sizeof(long) on Python version < 1.5.2) is used as
 indicator for the supported pointer size.

 The function relies on the system's "file" command to do the
 actual work. This is available on most if not all Unix
 platforms. On some non-Unix platforms where the "file" command
 does not exist and the executable is set to the Python interpreter
 binary defaults from _default_architecture are used.

 """
 # Use the sizeof(pointer) as default number of bits if nothing
 # else is given as default.
 if not bits:
 import struct
 size = struct.calcsize('P')
 bits = str(size * 8) + 'bit'

 # Get data from the 'file' system command
 if executable:
 fileout = _syscmd_file(executable, '')
 else:
 fileout = ''

 if not fileout and \
 executable == sys.executable:
 # "file" command did not return anything; we'll try to provide
 # some sensible defaults then...
 if sys.platform in _default_architecture:
 b, l = _default_architecture[sys.platform]
 if b:
 bits = b
 if l:
 linkage = l
 return bits, linkage

 if 'executable' not in fileout and 'shared object' not in fileout:
 # Format not supported
 return bits, linkage

 # Bits
 if '32-bit' in fileout:
 bits = '32bit'
 elif 'N32' in fileout:
 # On Irix only
 bits = 'n32bit'
 elif '64-bit' in fileout:
 bits = '64bit'

 # Linkage
 if 'ELF' in fileout:
 linkage = 'ELF'
 elif 'PE' in fileout:
 # E.g. Windows uses this format
 if 'Windows' in fileout:
 linkage = 'WindowsPE'
 else:
 linkage = 'PE'
 elif 'COFF' in fileout:
 linkage = 'COFF'
 elif 'MS-DOS' in fileout:
 linkage = 'MSDOS'
 else:
 # XXX the A.OUT format also falls under this class...
 pass

 return bits, linkage

### Portable uname() interface

uname_result = collections.namedtuple("uname_result",
 "system node release version machine processor")

_uname_cache = None

def uname():

 """ Fairly portable uname interface. Returns a tuple
 of strings (system, node, release, version, machine, processor)
 identifying the underlying platform.

 Note that unlike the os.uname function this also returns
 possible processor information as an additional tuple entry.

 Entries which cannot be determined are set to ''.

 """
 global _uname_cache
 no_os_uname = 0

 if _uname_cache is not None:
 return _uname_cache

 processor = ''

 # Get some infos from the builtin os.uname API...
 try:
 system, node, release, version, machine = os.uname()
 except AttributeError:
 no_os_uname = 1

 if no_os_uname or not list(filter(None, (system, node, release, version, machine))):
 # Hmm, no there is either no uname or uname has returned
 #'unknowns'... we'll have to poke around the system then.
 if no_os_uname:
 system = sys.platform
 release = ''
 version = ''
 node = _node()
 machine = ''

 use_syscmd_ver = 1

 # Try win32_ver() on win32 platforms
 if system == 'win32':
 release, version, csd, ptype = win32_ver()
 if release and version:
 use_syscmd_ver = 0
 # Try to use the PROCESSOR_* environment variables
 # available on Win XP and later; see
 # http://support.microsoft.com/kb/888731 and
 # http://www.geocities.com/rick_lively/MANUALS/ENV/MSWIN/PROCESSI.HTM
 if not machine:
 # WOW64 processes mask the native architecture
 if "PROCESSOR_ARCHITEW6432" in os.environ:
 machine = os.environ.get("PROCESSOR_ARCHITEW6432", '')
 else:
 machine = os.environ.get('PROCESSOR_ARCHITECTURE', '')
 if not processor:
 processor = os.environ.get('PROCESSOR_IDENTIFIER', machine)

 # Try the 'ver' system command available on some
 # platforms
 if use_syscmd_ver:
 system, release, version = _syscmd_ver(system)
 # Normalize system to what win32_ver() normally returns
 # (_syscmd_ver() tends to return the vendor name as well)
 if system == 'Microsoft Windows':
 system = 'Windows'
 elif system == 'Microsoft' and release == 'Windows':
 # Under Windows Vista and Windows Server 2008,
 # Microsoft changed the output of the ver command. The
 # release is no longer printed. This causes the
 # system and release to be misidentified.
 system = 'Windows'
 if '6.0' == version[:3]:
 release = 'Vista'
 else:
 release = ''

 # In case we still don't know anything useful, we'll try to
 # help ourselves
 if system in ('win32', 'win16'):
 if not version:
 if system == 'win32':
 version = '32bit'
 else:
 version = '16bit'
 system = 'Windows'

 elif system[:4] == 'java':
 release, vendor, vminfo, osinfo = java_ver()
 system = 'Java'
 version = ', '.join(vminfo)
 if not version:
 version = vendor

 # System specific extensions
 if system == 'OpenVMS':
 # OpenVMS seems to have release and version mixed up
 if not release or release == '0':
 release = version
 version = ''
 # Get processor information
 try:
 import vms_lib
 except ImportError:
 pass
 else:
 csid, cpu_number = vms_lib.getsyi('SYI$_CPU', 0)
 if (cpu_number >= 128):
 processor = 'Alpha'
 else:
 processor = 'VAX'
 if not processor:
 # Get processor information from the uname system command
 processor = _syscmd_uname('-p', '')

 #If any unknowns still exist, replace them with ''s, which are more portable
 if system == 'unknown':
 system = ''
 if node == 'unknown':
 node = ''
 if release == 'unknown':
 release = ''
 if version == 'unknown':
 version = ''
 if machine == 'unknown':
 machine = ''
 if processor == 'unknown':
 processor = ''

 # normalize name
 if system == 'Microsoft' and release == 'Windows':
 system = 'Windows'
 release = 'Vista'

 _uname_cache = uname_result(system, node, release, version,
 machine, processor)
 return _uname_cache

### Direct interfaces to some of the uname() return values

def system():

 """ Returns the system/OS name, e.g. 'Linux', 'Windows' or 'Java'.

 An empty string is returned if the value cannot be determined.

 """
 return uname().system

def node():

 """ Returns the computer's network name (which may not be fully
 qualified)

 An empty string is returned if the value cannot be determined.

 """
 return uname().node

def release():

 """ Returns the system's release, e.g. '2.2.0' or 'NT'

 An empty string is returned if the value cannot be determined.

 """
 return uname().release

def version():

 """ Returns the system's release version, e.g. '#3 on degas'

 An empty string is returned if the value cannot be determined.

 """
 return uname().version

def machine():

 """ Returns the machine type, e.g. 'i386'

 An empty string is returned if the value cannot be determined.

 """
 return uname().machine

def processor():

 """ Returns the (true) processor name, e.g. 'amdk6'

 An empty string is returned if the value cannot be
 determined. Note that many platforms do not provide this
 information or simply return the same value as for machine(),
 e.g. NetBSD does this.

 """
 return uname().processor

### Various APIs for extracting information from sys.version

_sys_version_parser = re.compile(
 r'([\w.+]+)\s*' # "version<space>"
 r'\(#?([^,]+)' # "(#buildno"
 r'(?:,\s*([\w ]*)' # ", builddate"
 r'(?:,\s*([\w :]*))?)?\)\s*' # ", buildtime)<space>"
 r'\[([^\]]+)\]?', re.ASCII) # "[compiler]"

_ironpython_sys_version_parser = re.compile(
 r'IronPython\s*'
 r'([\d\.]+)'
 r'(?: \(([\d\.]+)\))?'
 r' on (.NET [\d\.]+)', re.ASCII)

# IronPython covering 2.6 and 2.7
_ironpython26_sys_version_parser = re.compile(
 r'([\d.]+)\s*'
 r'\(IronPython\s*'
 r'[\d.]+\s*'
 r'\(([\d.]+)\) on ([\w.]+ [\d.]+(?: \(\d+-bit\))?)\)'
)

_pypy_sys_version_parser = re.compile(
 r'([\w.+]+)\s*'
 r'\(#?([^,]+),\s*([\w ]+),\s*([\w :]+)\)\s*'
 r'\[PyPy [^\]]+\]?')

_sys_version_cache = {}

def _sys_version(sys_version=None):

 """ Returns a parsed version of Python's sys.version as tuple
 (name, version, branch, revision, buildno, builddate, compiler)
 referring to the Python implementation name, version, branch,
 revision, build number, build date/time as string and the compiler
 identification string.

 Note that unlike the Python sys.version, the returned value
 for the Python version will always include the patchlevel (it
 defaults to '.0').

 The function returns empty strings for tuple entries that
 cannot be determined.

 sys_version may be given to parse an alternative version
 string, e.g. if the version was read from a different Python
 interpreter.

 """
 # Get the Python version
 if sys_version is None:
 sys_version = sys.version

 # Try the cache first
 result = _sys_version_cache.get(sys_version, None)
 if result is not None:
 return result

 # Parse it
 if 'IronPython' in sys_version:
 # IronPython
 name = 'IronPython'
 if sys_version.startswith('IronPython'):
 match = _ironpython_sys_version_parser.match(sys_version)
 else:
 match = _ironpython26_sys_version_parser.match(sys_version)

 if match is None:
 raise ValueError(
 'failed to parse IronPython sys.version: %s' %
 repr(sys_version))

 version, alt_version, compiler = match.groups()
 buildno = ''
 builddate = ''

 elif sys.platform.startswith('java'):
 # Jython
 name = 'Jython'
 match = _sys_version_parser.match(sys_version)
 if match is None:
 raise ValueError(
 'failed to parse Jython sys.version: %s' %
 repr(sys_version))
 version, buildno, builddate, buildtime, _ = match.groups()
 if builddate is None:
 builddate = ''
 compiler = sys.platform

 elif "PyPy" in sys_version:
 # PyPy
 name = "PyPy"
 match = _pypy_sys_version_parser.match(sys_version)
 if match is None:
 raise ValueError("failed to parse PyPy sys.version: %s" %
 repr(sys_version))
 version, buildno, builddate, buildtime = match.groups()
 compiler = ""

 else:
 # CPython
 match = _sys_version_parser.match(sys_version)
 if match is None:
 raise ValueError(
 'failed to parse CPython sys.version: %s' %
 repr(sys_version))
 version, buildno, builddate, buildtime, compiler = \
 match.groups()
 name = 'CPython'
 if builddate is None:
 builddate = ''
 elif buildtime:
 builddate = builddate + ' ' + buildtime

 if hasattr(sys, '_git'):
 _, branch, revision = sys._git
 elif hasattr(sys, '_mercurial'):
 _, branch, revision = sys._mercurial
 else:
 branch = ''
 revision = ''

 # Add the patchlevel version if missing
 l = version.split('.')
 if len(l) == 2:
 l.append('0')
 version = '.'.join(l)

 # Build and cache the result
 result = (name, version, branch, revision, buildno, builddate, compiler)
 _sys_version_cache[sys_version] = result
 return result

def python_implementation():

 """ Returns a string identifying the Python implementation.

 Currently, the following implementations are identified:
 'CPython' (C implementation of Python),
 'IronPython' (.NET implementation of Python),
 'Jython' (Java implementation of Python),
 'PyPy' (Python implementation of Python).

 """
 return _sys_version()[0]

def python_version():

 """ Returns the Python version as string 'major.minor.patchlevel'

 Note that unlike the Python sys.version, the returned value
 will always include the patchlevel (it defaults to 0).

 """
 return _sys_version()[1]

def python_version_tuple():

 """ Returns the Python version as tuple (major, minor, patchlevel)
 of strings.

 Note that unlike the Python sys.version, the returned value
 will always include the patchlevel (it defaults to 0).

 """
 return tuple(_sys_version()[1].split('.'))

def python_branch():

 """ Returns a string identifying the Python implementation
 branch.

 For CPython this is the SCM branch from which the
 Python binary was built.

 If not available, an empty string is returned.

 """

 return _sys_version()[2]

def python_revision():

 """ Returns a string identifying the Python implementation
 revision.

 For CPython this is the SCM revision from which the
 Python binary was built.

 If not available, an empty string is returned.

 """
 return _sys_version()[3]

def python_build():

 """ Returns a tuple (buildno, builddate) stating the Python
 build number and date as strings.

 """
 return _sys_version()[4:6]

def python_compiler():

 """ Returns a string identifying the compiler used for compiling
 Python.

 """
 return _sys_version()[6]

### The Opus Magnum of platform strings :-)

_platform_cache = {}

def platform(aliased=0, terse=0):

 """ Returns a single string identifying the underlying platform
 with as much useful information as possible (but no more :).

 The output is intended to be human readable rather than
 machine parseable. It may look different on different
 platforms and this is intended.

 If "aliased" is true, the function will use aliases for
 various platforms that report system names which differ from
 their common names, e.g. SunOS will be reported as
 Solaris. The system_alias() function is used to implement
 this.

 Setting terse to true causes the function to return only the
 absolute minimum information needed to identify the platform.

 """
 result = _platform_cache.get((aliased, terse), None)
 if result is not None:
 return result

 # Get uname information and then apply platform specific cosmetics
 # to it...
 system, node, release, version, machine, processor = uname()
 if machine == processor:
 processor = ''
 if aliased:
 system, release, version = system_alias(system, release, version)

 if system == 'Darwin':
 # macOS (darwin kernel)
 macos_release = mac_ver()[0]
 if macos_release:
 system = 'macOS'
 release = macos_release

 if system == 'Windows':
 # MS platforms
 rel, vers, csd, ptype = win32_ver(version)
 if terse:
 platform = _platform(system, release)
 else:
 platform = _platform(system, release, version, csd)

 elif system in ('Linux',):
 # check for libc vs. glibc
 libcname, libcversion = libc_ver(sys.executable)
 platform = _platform(system, release, machine, processor,
 'with',
 libcname+libcversion)
 elif system == 'Java':
 # Java platforms
 r, v, vminfo, (os_name, os_version, os_arch) = java_ver()
 if terse or not os_name:
 platform = _platform(system, release, version)
 else:
 platform = _platform(system, release, version,
 'on',
 os_name, os_version, os_arch)

 else:
 # Generic handler
 if terse:
 platform = _platform(system, release)
 else:
 bits, linkage = architecture(sys.executable)
 platform = _platform(system, release, machine,
 processor, bits, linkage)

 _platform_cache[(aliased, terse)] = platform
 return platform

### Command line interface

if __name__ == '__main__':
 # Default is to print the aliased verbose platform string
 terse = ('terse' in sys.argv or '--terse' in sys.argv)
 aliased = (not 'nonaliased' in sys.argv and not '--nonaliased' in sys.argv)
 print(platform(aliased, terse))
 sys.exit(0)