Make call of os.getppid() conditional: it is not available on Windows.
diff --git a/Doc/library/multiprocessing.rst b/Doc/library/multiprocessing.rst
index 303cdbc..bac9cf0 100644
--- a/Doc/library/multiprocessing.rst
+++ b/Doc/library/multiprocessing.rst
@@ -81,7 +81,8 @@
     def info(title):
         print title
         print 'module name:', __name__
-        print 'parent process:', os.getppid()
+        if hasattr(os, 'getppid'):  # only available on Unix
+            print 'parent process:', os.getppid()
         print 'process id:', os.getpid()
 
     def f(name):