百度试题 结果1 题目:pthread_rwlock_rdlock是对读写锁进行___操作。 A. 加锁 B. 解锁 C. 加读琐 D. 加写锁 相关知识点: 试题来源: 解析 C 反馈 收藏
一个线程可能在 rwlock 上持有多个并发读锁定 (即,成功调用 pthread_rwlock_rdlock 函数n 次)。 如果是这样,那么线程必须执行匹配的解锁 (即,它必须调用 pthread_rwlock_unlock 函数n 次)。 函数pthread_rwlock_tryrdlock 会像在 pthread_rwlock_rdlock 函数中一样应用读锁定,但如果任何线程在 rwlock 上持有写锁定...
pthread_rwlock_rdlock () 函数将读锁定应用于rwlock引用的读或写锁定。 如果写程序未持有该锁,并且该锁上没有被阻止的写程序,那么调用线程将获取读锁。 在z/OS UNIX中,当写程序未持有该锁定并且有写程序等待该锁定时,调用线程不会获取该锁定,除非该线程已持有rwlock以供读取。 它将阻塞并等待直到没有写程序挂...
pthread_rwlock_rdlock(&rwlock); printf("Read Thread(%x) counter=%d\n", (int)pthread_self(), counter); pthread_rwlock_unlock(&rwlock); usleep(100); } }intmain() {inti; pthread_t tid[8]; pthread_rwlock_init(&rwlock, NULL);for(i=0; i<3; i++) pthread_create(&tid[i], NULL, ...
A thread may hold multiple concurrent read locks on rwlock (that is, successfully call the pthread_rwlock_rdlock() function n times). If so, the thread must perform matching unlocks (that is, it must call the pthread_rwlock_unlock() function n times). The function pthread_rwlock_tryrdlock...
Return Value If successful,pthread_rwlock_rdlock()returns zero. Otherwise, an error number is returned to indicate the error. EINVAL The value specified byattrorrwlockis invalid.
pthread_rwlock_rdlock pthread_rwlock_wrlock pthread_rwlock_tryrdlock pthread_rwlock_trywrlock pthread_rwlock_unlock ⽰例代码：#include <pthread.h> #include <stdio.h> #include <unistd.h> static int counter;static pthread_rwlock_t rwlock;void *th_write(void *arg){ int t, i;for (i=0; i<...
pthread_rwlock_rdlock和“No such file or directory”调用pthread_rwlock_rdlock时,如果失败报错“pthread_rwlock_rdlock”,则可能是因为对同一把锁先加了写锁,再加读锁时就报这个错误了。...
undefined reference to `pthread_rwlock_destroy' /home/cathal/torch-cl/install/lib/libclBLAS.so: undefined reference to `pthread_rwlock_rdlock' /home/cathal/torch-cl/install/lib/libclBLAS.so: undefined reference to `pthread_rwlock_init' /home/cathal/torch-cl/install/lib/libclBLAS.so: undefined...
If successful, pthread_rwlock_rdlock() returns 0. If unsuccessful, pthread_rwlock_rdlock() returns -1 and sets errno to one of the following values: Error Code Description EAGAIN The read lock could not be acquired because the maximum number of read locks forrwlockhas been exceeded. T...