# :mod:sphinx.ext.oldcmarkup -- Compatibility extension for old C markup

This extension is a transition helper for projects that used the old (pre-domain) C markup, i.e. the directives like cfunction and roles like cfunc. Since the introduction of domains, they must be called by their fully-qualified name (c:function and c:func, respectively) or, with the default domain set to c, by their new name (function and func). (See :ref:c-domain for the details.)

If you activate this extension, it will register the old names, and you can use them like before Sphinx 1.0. The directives are:

• cfunction
• cmember
• cmacro
• ctype
• cvar

The roles are:

• cdata
• cfunc
• cmacro
• ctype

However, it is advised to migrate to the new markup -- this extension is a compatibility convenience and will disappear in a future version of Sphinx.