In UNIX, a signal is a mechanism by which a process may be notified of an event or affected by an event occurring in the system. The access methods do not perform any type of signal processing. The only signal that might be expected is when a FIFO breaks, such as when the reader closes the file and a writer tries to write to it. This results in a signal (SIGPIPE) that is sent to the writer. The default action for the signal terminates the writer's task with an abend EC6-FF0D.