trap "exception" signals

[mathias]

So @twopoint718 actually suggested this: use trap to be able to capture and keep track of signals sent by something running inside an assertion.

http://tldp.org/LDP/Bash-Beginners-Guide/html/sect_12_02.html

[nwmcsween]

You would need a 'trap handler' as another test script could hook trap and the assert trap handler would stomp on it.