or to be less chatty on the wire, something like:

```rb
def wait(*channels)
  command = []
  channels.each do |chan|
    command.push('LISTEN "' + chan + '"')
  end
  execute(%|LISTEN "#{command.join(';')}"|)
  wait_for_notify(WAIT_TIME)
  channels.each do |chan|
    execute('UNLISTEN *')
  end
  drain_notify
end
```