__register_atfork
extern status_t __register_atfork(void(*prepare)(void), void(*parent)(void),
extern int __register_atfork(void (*)(void), void(*)(void), void (*)(void), void *);
#define _ARC4_ATFORK(f) __register_atfork(NULL, NULL, (f), __dso_handle)
return __register_atfork(prepare, parent, child);
status_t status = __register_atfork(NULL, NULL, function);