Use source reST role instead of file where it makes sense.
source generates a nifty link to the Mercurial web viewer.
diff --git a/Doc/howto/cporting.rst b/Doc/howto/cporting.rst
index 98db9dd..bea2153 100644
--- a/Doc/howto/cporting.rst
+++ b/Doc/howto/cporting.rst
@@ -261,8 +261,8 @@
copy as you see fit.)
You can find :file:`capsulethunk.h` in the Python source distribution
-in the :file:`Doc/includes` directory. We also include it here for
-your reference; here is :file:`capsulethunk.h`:
+as :source:`Doc/includes/capsulethunk.h`. We also include it here for
+your convenience:
.. literalinclude:: ../includes/capsulethunk.h