Well, it's not exactly what you describe (which does sound kind of intriguing), but Linux does offer the signalfd(2) syscall, which allows you to read signals f

Well, it's not exactly what you describe (which does sound kind of intriguing), but Linux does offer the signalfd(2) syscall, which allows you to read signals from a file descriptor. Doesn't do much for the sender of said signals, however.