I need to create an asynchronous sub-process that will run until terminated or will terminate automatically when the parent process terminates. Will a subprocess behave that way? Is it OK to have dangling sub-processes (i.e. a subprocess with no actions defined afterwards)?
Yes, you can have the dangling process. The parent process will not complete until the subprocess completes. If you delete or cancel the parent process, the child process will also be deleted or canceled.