Linux下的C语言编程有多种线程同步机制,最典型的是条件变量(condition variable)。pthread_cond_init用来创建一个条件变量,其函数原型为: pthread_cond_init (pthread_cond_t*cond,constpthread_condattr_t*attr); pthread_cond_wait和pthread_cond_timedwait
也就是说如果pthread_cond_wait()被取消,mutex是保持锁定状态的,因而需要定义退出回调函数来为其解锁。 EXAMPLE Consider two shared variables x and y, protected by the mutex mut, and a condition variable cond that is to be signaled whenever x becomes greater than y. int x,y; pthread_mutex_t mu...
问pthread_cond_t与std::condition_variable的差异EN我最近正在测试std::condition_variable，并且在测试后...
Some implementations, particularly on a multi-processor, may sometimes cause multiple threads to wake up when the condition variable is signaled simultaneously on different processors. In general, whenever a condition wait returns, the thread has to re-evaluate the predicate associated with the conditio...
(pm)#definepthread_cond_t CONDITION_VARIABLE#definepthread_cond_init(pc, a) InitializeConditionVariable(pc)#definepthread_cond_wait(pc, pm) SleepConditionVariableCS(pc, pm, INFINITE)#definepthread_cond_signal(pc) WakeConditionVariable(pc)#definepthread_cond_broadcast(pc) WakeAllConditionVariable(pc...
编译需求:使用pthread_cond_timedwait64函数需要long long数据类型。 有关如何使long long数据类型可用的更多信息,请参阅z/OS XL C/C++ Language Reference。 一般描述 允许线程在条件变量上等待,直到满足或发生指定的时间为止。pthread_cond_timedwait()与pthread_cond_wait()相同,但如果abstime指定的...
attrによって参照された属性を使用して、condによって 参照された条件変数を初期設定します。attrが NULL の場合には、デフォルト条件変数属性が使用されます。 戻り値 正常に実行された場合、pthread_cond_init() は 0 を戻します。 正常に実行されなかった場合、pthread_cond_init() は -1 を戻し...
A condition variable can be statically initialized by assigningPTHREAD_COND_INITIALIZERin its definition, as follows: pthread_cond_t def_cond = PTHREAD_COND_INITIALIZER; A condition variable must be initialized (either by callingpthread_cond_init(), or statically) before it may be used in any ot...
无论哪种等待方式,都必须和一个互斥锁配合,以防止多个线程同时请求pthread_cond_wait()(或pthread_cond_timedwait(),下同)的竞争条件(Race Condition)。mutex互斥锁必须是普通锁(PTHREAD_MUTEX_TIMED_NP)或者适应锁(PTHREAD_MUTEX_ADAPTIVE_NP),且在调用pthread_cond_wait()前必须由本线程加锁(pthread_mutex_lock...
Each of the three major classes of routines in the Pthreads API are then covered: Thread Management, Mutex Variables, and Condition Variables. Example codes are used throughout to demonstrate how to use most of the Pthreads routines needed by a new Pthreads programmer. The tutorial concludes ...