akuma: Embeddable daemonization library -
This library also lets you write a multi-process network server that listens on the same TCP/IP port. By forking multiple processes, you improve the robustness of your server --- a single destroyed process will not interrupt the service as other worker processes will take over the processing.
This is how Unix daemons have been traditionally written, such as Apache, yet it was impossible to do this in Java because it doesn't provide an API to let file descriptors to be inherited into children.