vc-cvs-append-to-ignore
vc-cvs-append-to-ignore is a compiled Lisp function in `vc-cvs.el
'.
(vc-cvs-append-to-ignore DIR STR &optional OLD-DIR)
In DIR, add STR to the .cvsignore file.
If OLD-DIR is non-nil, then this is a directory that we don't want
to hear about anymore.