The premise is faulty. Subprocesses are fine, it is the POSIX shell that should be avoided. Or any interpreted language. Smallest tool for the job. Use exec* c

The premise is faulty. Subprocesses are fine, it is the POSIX shell that should be avoided. Or any interpreted language. Smallest tool for the job. Use exec* calls, right options for your process handling class and there is no problem. As a bonus feel free to spawn/fork your current application. Linking pipes and file descriptors is also not that hard. (Though they are a cruddy that may be nicer to wrap in something like 0mq.)