How does an application recognize the death of the postmaster

How do folks handle the death of the postmaster in their applications?
Assuming the postmaster dies after an application has connected to the
database, but before it makes a request.  What should I look for?
Currently our application that's in development does not handle the
situation well.  What we want to do is gracefully (as possible) shutdown
the application.

--
Until later, Geoffrey

Any society that would give up a little liberty to gain a little
security will deserve neither and lose both.  - Benjamin Franklin