The code in PosixPlatform.cpp:

    //TODO Use waitpid instead of wait
#ifdef LINUX
    wait();
#endif
#ifdef MAC
    wpid = wait(&status);
#endif

would be more correct to be using waitpid instead of wait. I didn't have good luck using waitpid and there is no good reason at the moment to spin up two processes so wait works, however waitpid is more correct.