int pthread_spin_init(pthread_spinlock_t *lock,int pshared)请求OS对*lock初始化,分配资源,flag设为已开锁,将它的线程等待队列置为NULL.pshared有两个可选值 ◼ PTHREAD_PROCESS_SHARED:对*lock执行“加锁”的线程与当前线 程可以分别属于不同的进程。 ◼ PTHREAD_PROCESS_PRIVATE:对*lock执行“加锁”的...
PTHREAD_SPINLOCK_INITIALIZER int pthread_spin_init (__pthread_spinlock_t *__lock, int __pshared); int pthread_spin_destroy (__pthread_spinlock_t *__lock); int pthread_spin_trylock (__pthread_spinlock_t *__lock); int pthread_spin_unlock (__pthread_spinlock_t *__lock); int pthread_s...
在子线程返回后,主线程会一直卡在acquire lock这里,不会success,说明在pthread_cond_wait里面确实有加锁的操作,此时如没有释放锁,其他线程获取锁将会进入死锁状态,所以在pthread_cond_wait使用前后,一定要使用pthread_mutex_lock和pthread_mutex_unlock。 pthread自旋锁(spinlock) 自旋锁与互斥锁比较类似,它们都是为了...
1.1 锁的创建 锁可以被动态或静态创建,可以用宏PTHREAD_MUTEX_INITIALIZER来静态的初始化锁,采用这种方式比较容易理解,互斥锁是pthread_mutex_t的结构体,而这个宏是一个结构常量,如下可以完成静态的初始化锁: pthread_mutex_t mutex =PTHREAD_MUTEX_INITIALIZER; 另外锁可以用pthread_mutex_init函数动态的创建,函数原型...
#define PTHREAD_COND_INITIALIZER ((pthread_cond_t)(size_t) -1) #define PTHREAD_RWLOCK_INITIALIZER ((pthread_rwlock_t)(size_t) -1) #define PTHREAD_SPINLOCK_INITIALIZER ((pthread_spinlock_t)(size_t) -1) /* * Mutex types. */ enum { /* Compatibility with LinuxThreads */ ...
#include<pthread.h>/* define and initialize a mutex named `mutex' */pthread_mutex_t mutex=PTHREAD_MUTEX_INITIALIZER;intpthread_mutex_init(pthread_mutex_t*restrict mutex,constpthread_mutexattr_t*restrict attr);intpthread_mutex_destroy(pthread_mutex_t*mutex);//Both return: 0 if OK, error numb...
#define PTHREAD_SPINLOCK_INITIALIZER 0 typedef long pthread_spinlock_t; static int pthread_spin_init(pthread_spinlock_t *l, int pshared) { (void) pshared; *l = 0; return 0; } static int pthread_spin_destroy(pthread_spinlock_t *l) { (void) l; return 0; } /* No-fair spinlock ...
int pthread_spin_unlock(pthread_spinlock_t *); int pthread_spin_trylock(pthread_spinlock_t *); 初始化时第二个参数指定: PTHREAD_PROCESS_SHARED:该自旋锁可以在多个进程中的线程之间共享。 PTHREAD_PROCESS_PRIVATE: 仅初始化本自旋锁的线程所在的进程内的线程才能够使用该自旋锁。
#define PTHREAD_COND_INITIALIZER ((pthread_cond_t) -1)#define PTHREAD_RWLOCK_INITIALIZER ((pthread_rwlock_t) -1)#define PTHREAD_SPINLOCK_INITIALIZER ((pthread_spinlock_t) -1)/* * Mutex types. */ enum { /* Compatibility with LinuxThreads */...
pthread_cond_t condition = PTHREAD_COND_INITIALIZER;//静态初始化条件变量 pthread_cond_wait(pthread_cond_t * cond, pthread_mutex_t * mutex);//该函数以阻塞方式执行。如果某个线程中的程序执行了该函数,那么这个线程就会以阻塞方式等待,直到收到pthread_cond_signal或者pthread_cond_broadcast函数发来的信号...