erc-netsplit-mode
erc-netsplit-mode is an interactive autoloaded compiled Lisp function in `erc-netsplit.el
'.
(erc-netsplit-mode &optional ARG)
Toggle ERC netsplit mode.
With a prefix argument ARG, enable netsplit if ARG is positive,
and disable it otherwise. If called from Lisp, enable the mode
if ARG is omitted or nil.
This mode hides quit/join messages if a netsplit occurs.