Issue4064: architecture string for universal builds on OSX
diff --git a/Doc/distutils/apiref.rst b/Doc/distutils/apiref.rst
index a8f7461..a932fbd 100644
--- a/Doc/distutils/apiref.rst
+++ b/Doc/distutils/apiref.rst
@@ -1100,6 +1100,23 @@
For non-POSIX platforms, currently just returns ``sys.platform``.
+ For MacOS X systems the OS version reflects the minimal version on which
+ binaries will run (that is, the value of ``MACOSX_DEPLOYMENT_TARGET``
+ during the build of Python), not the OS version of the current system.
+
+ For universal binary builds on MacOS X the architecture value reflects
+ the univeral binary status instead of the architecture of the current
+ processor. For 32-bit universal binaries the architecture is ``fat``,
+ for 4-way universal binaries the architecture is ``universal``.
+
+ Examples of returned values on MacOS X:
+
+ * ``macosx-10.3-ppc``
+
+ * ``macosx-10.3-fat``
+
+ * ``macosx-10.5-universal``
+
.. % XXX isn't this also provided by some other non-distutils module?