How do I stop testing in Python unittest tearDown()?

I've got a large number of tests written using Python unittest (Python 2.7.8) as a large TestSuite. Many of these tests invoke other programs. Sometimes these other programs dump core. When they do, I want to discover that and ensure the test fails. If some number of cores are dumped, I want to abort the entire test environment and exit rather than continuing: my total test suite has >6000 tests and if everything is dumping core it's useless (and dangerous: disk space etc.) to continue.

In order to ensure we look for coredumps after every test (so I have the best possible idea of what program/invocation dumped core) I decided to look for cores in tearDown(), which I am doing successfully. If I find a core, I can run an assert variant in tearDown() to specify that the test failed.

But I can't figure out how to just give up on all my testing completely from within tearDown() if I find too many cores. I even tried to run sys.exit("too many cores"), but unittest case.py catches every exception thrown by tearDown() except KeyboardInterrupt (if I try to raise that by hand my script hangs until I do a real ^C).

I thought about trying to call stop(), but this is a method on the result and I can't find any way to get access to the result object from within tearDown() (!).

So far my only option seems to be to invoke os._exit() which is really annoying because it keeps any results from being reported at all!

Is there really no facility in Python unittest.TestCase to tell the test environment to just stop right now, generate what results you have but don't run anything else?