Script_API question

What is the recommended way for a pre-dle-something script
to definitely cause the DLE to be aborted for the current run?
Will the DLE processing be aborted if the script exits != 0?
Or, is there a particular message format to stdout that will
have that effect?

There should be a way for a script to ensure that a bad backup
is not made, if the script did not succeed in doing whatever
it is meant to do, but the Script_API page is not explicit
about that.

-Chap