useconds_t
useconds_t Otto_pause = 55000;
useconds_t
ualarm(useconds_t, useconds_t);
int usleep(useconds_t);
useconds_t
ualarm(useconds_t usecs, useconds_t reload)
int __usleep(useconds_t);
__usleep(useconds_t useconds)
int ___usleep(useconds_t);
___usleep(useconds_t useconds)
extern int __usleep(useconds_t);