cancel_safe_mutex_trylock
extern int cancel_safe_mutex_trylock(mutex_t *);
extern int cancel_safe_mutex_trylock(mutex_t *);
if (cancel_safe_mutex_trylock(lk) != 0)
if (cancel_safe_mutex_trylock(lk) != 0)
if (lk != NULL && cancel_safe_mutex_trylock(lk) != 0)