Lib/platform.py

Source:

cpython 3.14 @ ab2d84fe1023/Lib/platform.py ↗

platform provides a cross-platform interface for querying system information: OS name, version, machine architecture, processor type, Python version, and implementation. Most data is read from os.uname(), sys.version, and optional platform-specific APIs. Results are cached after first call.

Map

Lines	Symbol	Role
1-80	imports, constants	os, sys, struct
81-200	uname, uname_result	os.uname() wrapper with caching
201-350	system, node, release, version, machine, processor	Individual field accessors
351-450	architecture	Pointer size and linkage model
451-600	python_version, python_version_tuple, python_build, python_compiler, python_branch, python_revision, python_implementation	Python interpreter metadata
601-750	platform	Formatted one-line platform string
751-980	Windows/macOS/Linux-specific helpers	win32_ver, mac_ver, libc_ver, freedesktop_os_release

Reading

uname and caching

uname() returns a uname_result named tuple wrapping os.uname(). The result is cached in a module-level variable after the first call.

# CPython: Lib/platform.py:92 uname
_uname_cache = None

def uname():
    global _uname_cache
    if _uname_cache is not None:
        return _uname_cache
    ...
    _uname_cache = uname_result(system, node, release, version, machine, processor)
    return _uname_cache

architecture

# CPython: Lib/platform.py:380 architecture
def architecture(executable=sys.executable, bits='', linkage=''):
    ...
    size = struct.calcsize('P') * 8
    ...

Reads the pointer size (struct.calcsize('P') * 8) to determine 32-bit vs 64-bit. On some platforms it also reads the ELF header or Mach-O magic to detect the linkage model.

python_implementation

# CPython: Lib/platform.py:480 python_implementation
def python_implementation():
    return sys.implementation.name

Returns 'CPython' for the reference interpreter, 'PyPy' for PyPy, etc.

freedesktop_os_release (Linux)

Reads /etc/os-release or /usr/lib/os-release and returns a dict of key-value pairs following the freedesktop.org spec. This is the modern way to identify Linux distributions.

# CPython: Lib/platform.py:880 freedesktop_os_release
def freedesktop_os_release():
    ...
    with open('/etc/os-release', encoding='utf-8') as f:
        ...

gopy notes

Status: not yet ported. platform is a thin wrapper around os.uname(), sys.version, and sys.implementation. All data is available from Go's runtime package (runtime.GOOS, runtime.GOARCH) and os.Hostname(). The python_* family of functions should return gopy-specific values, e.g., python_implementation() returns 'gopy'.