全局变量:
int REGISTRATION_SIZE = 10;
我想将全局变量(REGISTRATION_SIZE)作为方法参数传递给 wait_for_avaliable 方法,例如 wait_for_avaliable(int size)。我怎样才能做到这一点?
void wait_for_available_resource(struct Patient *p, pthread_mutex_t *registration_mutex, pthread_cond_t *register_cond){
int rnd_wait_time;
pthread_mutex_lock(registration_mutex);
while(REGISTRATION_SIZE == 0){
rnd_wait_time = generate_rnd_numb(WAIT_TIME) + 1;
printf("Patient[%d] is waiting for an availabe desk.\n",p->thread_num);
sleepForMs(rnd_wait_time);
increase_meters(p);
checkForRestOrCafe(p);
pthread_cond_wait(register_cond,registration_mutex);
}
REGISTRATION_SIZE--;
printf("Registration size:%d\n",REGISTRATION_SIZE);
pthread_mutex_unlock(registration_mutex);
}
我尝试过这种方式,但它不起作用:
void wait_for_available_resource(struct Patient *p, pthread_mutex_t *registration_mutex, pthread_cond_t *register_cond, int *size){
int rnd_wait_time;
pthread_mutex_lock(registration_mutex);
while(size == 0){
rnd_wait_time = generate_rnd_numb(WAIT_TIME) + 1;
printf("Patient[%d] is waiting for an availabe desk.\n",p->thread_num);
sleepForMs(rnd_wait_time);
increase_meters(p);
checkForRestOrCafe(p);
pthread_cond_wait(register_cond,registration_mutex);
}
size--;
printf("Registration size:%d\n",size);
pthread_mutex_unlock(registration_mutex);
}