如果有多个线程为了获得该mutex锁阻塞,调用pthread_mutex_unlock()将是该mutex可用,一定的调度策略将被用来决定哪个线程可以获得该mutex锁。(在mutex类型为PTHREAD_MUTEX_RECURSIVE的情况下,只有当lock count减为0并且调用线程在该mutex上已经没有锁的时候)(翻译到这里,才觉得我的这个锁概念是多么模糊) 如果一个线程在...
pthread_mutex_t mutex = PTHREAD_MUTEX_INITIALIZER; void * myThread(void *arg){ int id = *(int *)arg; int i; //printf("current thread is :%d\n",id); printf("child thread locked: %d\n",id); //线程操作前要加锁 pthread_mutex_lock(&mutex); printf("child thread unlocked: %d\n"...
如果调用方能够使状态保持一致,请针对该互斥锁调用pthread_mutex_consistent_np()并解除锁定该互斥锁。以后对pthread_mutex_lock()的调用都将正常进行。 如果调用方无法使状态保持一致,请勿针对该互斥锁调用pthread_mutex_init(),但要解除锁定该互斥锁。以后调用pthread_mutex_lock()时将无法获取该互斥锁,并且将返回错...
The mutex object referenced by mutex is locked by calling pthread_mutex_lock() . If the mutex is already locked, the calling thread blocks until the mutex becomes...
intpthread_mutex_lock(pthread_mutex_t*mutex); 1. 在Python中,我们可以使用ctypes库的CFUNCTYPE类来定义函数类型。下面是定义pthread_mutex_lock函数的代码: pthread_mutex_lock_prototype=ctypes.CFUNCTYPE(ctypes.c_int,ctypes.POINTER(pthread_mutex_t))defpthread_mutex_lock(mutex):# ... ...
pthread_mutex_t *mutex; int pthread_mutex_unlock (mutex) pthread_mutex_t *mutex; 描述 通过调用pthread_mutex_lock来锁定mutex参数引用的互斥对象。 如果互斥对象已锁定,那么调用线程将阻塞,直到互斥对象变为可用为止。 此操作将返回由处于锁定状态的mutex参数引用的互斥对象,调用线程作为其所有者。
futex全称是fast user-space locking,也就是快速用户空间锁,在linux下使用C语言写多线程程序时,在需要线程同步的地方会经常使用pthread_mutex_lock()函数对临界区进行加锁,如果加锁失败线程就会挂起,这就是互斥锁。但是pthread_mutex_lock并不是立即进行系统调用,而是首先在用户态进行CAS操作,判断其它线程是否已经获取...
{pthread_mutex_lock(&g_mutex);printf("producer get lock...\n");if(g_share.count<BUFFER_SIZE){g_share.buf[g_share.count++]=g_ch++;printf("produer got char [%c]\n",g_ch-1);if(g_share.count==BUFFER_SIZE){printf("Producer singaling full. \n");pthread_cond_signal(&g_cond)...
#define _UNIX03_THREADS #include <pthread.h> int pthread_mutex_lock(pthread_mutex_t *mutex); General description Locks a mutex object, which identifies a mutex. Mutexes are used to protect shared resources. If the mutex is already locked by another thread, the thread waits for the mutex to...