erc-server-INVITE-functions is a variable defined in `erc-backend.el'.
Its value is
erc-server-INVITE
This variable may be risky if used as a file-local variable.
Documentation:
Hook called upon receiving a INVITE server response.
Each function is called with two arguments, the process associated
with the response and the parsed response. If the function returns
non-nil, stop processing the hook. Otherwise, continue.
See also `erc-server-INVITE'.