update to new C roles and directives
diff --git a/Doc/library/commands.rst b/Doc/library/commands.rst
index 916e4a5..46ff823 100644
--- a/Doc/library/commands.rst
+++ b/Doc/library/commands.rst
@@ -38,7 +38,7 @@
``(status, output)``. *cmd* is actually run as ``{ cmd ; } 2>&1``, so that the
returned output will contain output or error messages. A trailing newline is
stripped from the output. The exit status for the command can be interpreted
- according to the rules for the C function :cfunc:`wait`.
+ according to the rules for the C function :c:func:`wait`.
.. function:: getoutput(cmd)