cvs-update is an interactive autoloaded compiled Lisp function in `pcvs.el'.

(cvs-update DIRECTORY FLAGS)

Run a `cvs update' in the current working DIRECTORY.
Feed the output to a *cvs* buffer and run `cvs-mode' on it.
With a C-u prefix argument, prompt for a directory to use.
A prefix arg >8 (ex: C-u C-u),
prevents reuse of an existing *cvs* buffer.
The prefix is also passed to `cvs-flags-query' to select the FLAGS
passed to cvs.