systemd is a suite of tools that run on a single host and manage functionality on a single host. That seems like the scale of any program on systemd would not be too crazy relative to an internet service, for example. Which makes me wonder: what benefit is any Linux specific API calls? Usually OS-specific API calls are for scaling reasons. What is systemd doing where it really need a LInux-specific API for an event loop?
Which makes me wonder: what benefit is any Linux specific API calls?
Linux-specific APIs are generally either much nicer to use, or there simply isn’t any cross-platform APIs for it.
In the case of epoll, however, other implementations of the same concept (kqueue) or abstractions (libevent) are arguably much nicer.