This one is new. $ fexit <program> args runs the program until exit or termination, and on that event dumps out a stack backtrace (and perhaps other information). Useful for stuff like: Running testProcMask(frysk.sys.TestSigSet) ...Aborted (core dumped) where, initially, I'd like to just get a stack-back-trace from that abort() call.
a.k.a. fedex?
Once this is basically working, state should change to suspended, and bugs against this made blockers to it.