Issue #12326: document the recommended idiom for checking sys.platform on Unix systems.
Also, point to the various alternatives.
diff --git a/Doc/library/os.rst b/Doc/library/os.rst
index c412ee1..5c84e85 100644
--- a/Doc/library/os.rst
+++ b/Doc/library/os.rst
@@ -61,6 +61,13 @@
names have currently been registered: ``'posix'``, ``'nt'``, ``'mac'``,
``'os2'``, ``'ce'``, ``'java'``.
+ .. seealso::
+ :attr:`sys.platform` has a finer granularity. :func:`os.uname` gives
+ system-dependent version information.
+
+ The :mod:`platform` module provides detailed checks for the
+ system's identity.
+
.. _os-filenames:
diff --git a/Doc/library/sys.rst b/Doc/library/sys.rst
index ae2dbf3..95dc662 100644
--- a/Doc/library/sys.rst
+++ b/Doc/library/sys.rst
@@ -714,6 +714,12 @@
For Unix systems, this is the lowercased OS name as returned by ``uname -s``
with the first part of the version as returned by ``uname -r`` appended,
e.g. ``'sunos5'`` or ``'linux2'``, *at the time when Python was built*.
+ Unless you want to test for a specific system version, it is therefore
+ recommended to use the following idiom::
+
+ if sys.platform.startswith('linux'):
+ # Linux-specific code here...
+
For other systems, the values are:
================ ===========================
@@ -726,6 +732,12 @@
OS/2 EMX ``'os2emx'``
================ ===========================
+ .. seealso::
+ :attr:`os.name` has a coarser granularity. :func:`os.uname` gives
+ system-dependent version information.
+
+ The :mod:`platform` module provides detailed checks for the
+ system's identity.
.. data:: prefix