Each attribute in this option names an apcupsd event and the string value it contains will be executed in a shell, in response to that event (prior to the default action). See “man apccontrol” for the list of events and what they represent. A hook script can stop apccontrol from doing its default action by exiting with value 99. Do not do this unless you know what you’re doing.

{ }

{
  doshutdown = "# shell commands to notify that the computer is shutting down";
}