The I]explain_exit_on_exit function may be used to have the
calling program print an explanation of its exit status (the value
passed to I]exit(3) or the return value from I]main)
immediately before it terminates.
The I]explain_exit_on_error function may be used to have the
calling program print an explanation of its exit status immediately
before it terminates, if that exit status is not EXIT_SUCCESS.
The I]explain_exit_cancel function may be used to
cancel the effect of the I]explain_exit_on_exit or
These functions may be called multiple times, and in any order. The
last called has precedence. The explanation will never be printed more