_ARC4_LOCK
#define _ARC4_LOCK() do {} while (0)
#define _ARC4_LOCK() \
#define _ARC4_LOCK() pthread_mutex_lock(&arc4random_mtx)
#define _ARC4_LOCK() pthread_mutex_lock(&arc4random_mtx)
#define _ARC4_LOCK() pthread_mutex_lock(&arc4random_mtx)
#define _ARC4_LOCK() pthread_mutex_lock(&arc4random_mtx)
#define _ARC4_LOCK() pthread_mutex_lock(&arc4random_mtx)
#define _ARC4_LOCK() pthread_mutex_lock(&arc4random_mtx)
#define _ARC4_LOCK() pthread_mutex_lock(&arc4random_mtx)
#define _ARC4_LOCK() { \