Merged revisions 83536,83546-83548,83550,83554-83555,83558,83563,83565,83571,83574-83575 via svnmerge from
svn+ssh://pythondev@svn.python.org/python/branches/py3k

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  r83536 | georg.brandl | 2010-08-02 19:49:25 +0200 (Mo, 02 Aug 2010) | 1 line

  #8578: mention danger of not incref'ing weak referenced object.
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  r83546 | georg.brandl | 2010-08-02 21:16:34 +0200 (Mo, 02 Aug 2010) | 1 line

  #7973: Fix distutils options spelling.
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  r83547 | georg.brandl | 2010-08-02 21:19:26 +0200 (Mo, 02 Aug 2010) | 1 line

  #7386: add example that shows that trailing path separators are stripped.
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  r83548 | georg.brandl | 2010-08-02 21:23:34 +0200 (Mo, 02 Aug 2010) | 1 line

  #8172: how does one use a property?
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  r83550 | georg.brandl | 2010-08-02 21:32:43 +0200 (Mo, 02 Aug 2010) | 1 line

  #9451: strengthen warning about __*__ special name usage.
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  r83554 | georg.brandl | 2010-08-02 21:43:05 +0200 (Mo, 02 Aug 2010) | 1 line

  #7280: note about nasmw.exe.
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  r83555 | georg.brandl | 2010-08-02 21:44:48 +0200 (Mo, 02 Aug 2010) | 1 line

  #8861: remove unused variable.
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  r83558 | georg.brandl | 2010-08-02 22:05:19 +0200 (Mo, 02 Aug 2010) | 1 line

  #8648: document UTF-7 codec functions.
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  r83563 | georg.brandl | 2010-08-02 22:21:21 +0200 (Mo, 02 Aug 2010) | 1 line

  #9037: add example how to raise custom exceptions from C code.
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  r83565 | georg.brandl | 2010-08-02 22:27:20 +0200 (Mo, 02 Aug 2010) | 1 line

  #9111: document that do_help() looks at docstrings.
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  r83571 | georg.brandl | 2010-08-02 22:44:34 +0200 (Mo, 02 Aug 2010) | 1 line

  Clarify that abs() is not a namespace.
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  r83574 | georg.brandl | 2010-08-02 22:47:56 +0200 (Mo, 02 Aug 2010) | 1 line

  #6867: epoll.register() returns None.
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  r83575 | georg.brandl | 2010-08-02 22:52:10 +0200 (Mo, 02 Aug 2010) | 1 line

  #9238: zipfile does handle archive comments.
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diff --git a/Doc/extending/extending.rst b/Doc/extending/extending.rst
index 5408b88..2d9594a 100644
--- a/Doc/extending/extending.rst
+++ b/Doc/extending/extending.rst
@@ -228,9 +228,28 @@
 become a dangling pointer. Should it become a dangling pointer, C code which
 raises the exception could cause a core dump or other unintended side effects.
 
-We discuss the use of PyMODINIT_FUNC as a function return type later in this
+We discuss the use of ``PyMODINIT_FUNC`` as a function return type later in this
 sample.
 
+The :exc:`spam.error` exception can be raised in your extension module using a
+call to :cfunc:`PyErr_SetString` as shown below::
+
+   static PyObject *
+   spam_system(PyObject *self, PyObject *args)
+   {
+       const char *command;
+       int sts;
+
+       if (!PyArg_ParseTuple(args, "s", &command))
+           return NULL;
+       sts = system(command);
+       if (sts < 0) {
+           PyErr_SetString(SpamError, "System command failed");
+           return NULL;
+       }
+       return PyLong_FromLong(sts);
+   }
+
 
 .. _backtoexample: