23.7.10 Customizing VC
The variable vc-handled-backends determines which version
control systems VC should handle. The default value is (RCS CVS
SVN SCCS Arch MCVS), so it contains all six version systems that are
currently supported. If you want VC to ignore one or more of these
systems, exclude its name from the list. To disable VC entirely, set
this variable to nil.
The order of systems in the list is significant: when you visit a file
registered in more than one system (see Local Version Control),
VC uses the system that comes first in vc-handled-backends by
default. The order is also significant when you register a file for
the first time, see Registering for details.
