People say "signals" as if they're just one thing, but I find it more useful to break them into two categories: * process-directed signals such as SIGHUP, SIGI

People say "signals" as if they're just one thing, but I find it more useful to break them into two categories: * process-directed signals such as SIGHUP, SIGINT, SIGWINCH, SIGTERM, SIGQUIT, SIGCHLD. They come from outside the process, including the `kill` command, the init system, and the terminal. For these, a dedicated signal-handling thread is a common, practical approach. Even if your program is single-threaded before implementing signal handling, creating a new thread might be the best approach. Or you could integrate signal handling with an event loop via the self-pipe trick. * thread-directed signals such as SIGSEGV, SIGFPE, SIGBUS (the preceding are all machine exceptions), SIGPIPE, SIGPROF, or anything sent by pthread_kill / pthread_sigqueue. If you need to handle these signals (usually for diagnostics), by definition you have to do it in the thread in question. And you almost certainly need a traditional signal(2) / sigaction(2) style signal handler.