RecvResponse reads a response object from the given reader.

SendResponse conveys to the caller a given response object o.

SafeExitCode is a sync storage for the exit code of a process the initial value of nil cannot be reset after the first set.

SafeSignal is a goroutine safe signalling mechanism It can have multiple goroutines that trigger the signal without interfering with eachother (or crashing as using a channel would) Currently designed for a single waiter goroutine.