rcirc-activity-functions is a variable defined in `rcirc.el'.
Its value is
nil
This variable may be risky if used as a file-local variable.
Documentation:
Hook to be run when there is channel activity.
Functions are called with a single argument, the buffer with the
activity. Only run if the buffer is not visible and
`rcirc-ignore-buffer-activity-flag' is non-nil.