There’s a relatively well-known Easter egg in BSD’s shutdown.c: a function named die_you_gravy_sucking_pig_dog. It turns out that Apple doesn’t care to have such uncouth function names floating around, so they re-defined it:
#ifdef __APPLE__
void log_and_exec_reboot_or_halt(void);
#else
void die_you_gravy_sucking_pig_dog(void);
#endif
Sure, it does the same thing, but I don’t think log_and_exec_reboot_or_halt has the same panache.