On Sun, Nov 18, 2018 at 09:42:35AM -0800, Andy Lutomirski wrote: > Now here's the kicker: if the "running program" calls execve(), it > goes away. The fd gets some sort of notification that this happened Type error, parser failed. Define "fd", please. If it's a "file descriptor", thank you do playing, you've lost. That's not going to work. If it's "opened file" (aka "file description" in horrible POSIXese), who's going to get notifications and what kind of exclusion are you going to use?