VS2022连接Linux操作pthread_rwlock_t等显示未定义标识符

使用VS2022社区版远程连接LInux(CentOS7)操作时,已经加入头文件#include的情况下,VS中使用pthread_rwlock_t 出现了未定义标识符的错误

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  • 这篇文章:C语言中的读写锁pthread_rwlock_t及使用方法介绍 也许能够解决你的问题,你可以看下
  • 除此之外, 这篇博客: Linux系统编程学习笔记中的 读写锁pthread_rwlock_t 部分也许能够解决你的问题, 你可以仔细阅读以下内容或跳转源博客中阅读:
  • 读写锁与互斥量类似, 但读写锁允许更高的并行性, 其特性为

    1. 写独占, 读共享
    2. 写锁优先级高(读写锁一起过来时)
    3. 锁只有一把

    读写锁只有一把, 但其具备两种状态:

    • 读模式下加锁状态(读锁)
    • 写模式下加锁状态(写锁)

    在这里插入图片描述
    当读线程远大于写线程, 可以调高访问效率

    读写锁操作函数:

    /*定义一个读写锁变量*/
    pthread_rwlock_t rwlock;
    
    int pthread_rwlock_init(&rwlock,NULL);
    int pthread_rwlock_destory(&rwlock);
    int pthread_rwlock_rdlock(&rwlock);
    int pthread_rwlock_wrlock(&rwlock);
    int pthread_rwlock_tryrdlock(&rwlock);
    int pthread_rwlock_trywrlock(&rwlock);
    int pthread_rwlock_unlock(&rwlock);
    

    都是成功返回0, 失败直接返回错误号

    读写锁代码示例:

    int cnt = 0;
    pthread_rwlock_t rwlock;
    
    void* writer(void* arg) {
    	long i = (long)arg;
    	while (1) {
    		pthread_rwlock_wrlock(&rwlock);
    		usleep(10000);
    		int t = cnt;
    		printf("I'm writer %ld, cnt = %d, ++cnt = %d\n", i, t, ++cnt);
    		pthread_rwlock_unlock(&rwlock);
    		usleep(100000);
    	}
    	return NULL;
    }
    
    void* reader(void* arg) {
    	long i = (long)arg;
    	while (1) {
    		pthread_rwlock_rdlock(&rwlock);
    		printf("I'm reader %ld, cnt = %d\n", i, cnt);
    		pthread_rwlock_unlock(&rwlock);
    		usleep(20000);
    	}
    	return NULL;
    }
    
    int main() {
    	pthread_rwlock_init(&rwlock, NULL);
    	pthread_t tid[8];
    	long i = 0;
    	for (; i < 3; ++i) {
    		pthread_create(tid + i, NULL, writer, (void*)i);
    	}
    	for (; i < 8; ++i) {
    		pthread_create(tid + 3 + i, NULL, reader, (void*)i);
    	}
    	for (i = 0; i < 8; ++i) {
    		pthread_join(tid[i], NULL);
    	}
    	pthread_rwlock_destroy(&rwlock);
    }
    

    现象:

    I'm writer 0, cnt = 0, ++cnt = 1
    I'm reader 3, cnt = 1
    I'm reader 4, cnt = 1
    I'm reader 5, cnt = 1
    I'm reader 6, cnt = 1
    I'm reader 7, cnt = 1
    I'm writer 1, cnt = 1, ++cnt = 2
    I'm writer 2, cnt = 2, ++cnt = 3
    I'm reader 6, cnt = 3
    I'm reader 3, cnt = 3
    I'm reader 5, cnt = 3
    I'm reader 4, cnt = 3
    I'm reader 7, cnt = 3
    I'm reader 3, cnt = 3
    I'm reader 5, cnt = 3
    I'm reader 6, cnt = 3
    I'm reader 4, cnt = 3
    I'm reader 7, cnt = 3
    I'm reader 6, cnt = 3
    I'm reader 5, cnt = 3
    I'm reader 4, cnt = 3
    I'm reader 3, cnt = 3
    I'm reader 7, cnt = 3
    I'm reader 4, cnt = 3
    I'm reader 5, cnt = 3
    I'm reader 3, cnt = 3
    I'm reader 6, cnt = 3
    I'm reader 7, cnt = 3
    I'm writer 0, cnt = 3, ++cnt = 4
    I'm reader 5, cnt = 4
    I'm reader 3, cnt = 4
    I'm reader 4, cnt = 4
    I'm reader 6, cnt = 4
    I'm reader 7, cnt = 4
    I'm writer 1, cnt = 4, ++cnt = 5
    I'm writer 2, cnt = 5, ++cnt = 6
    I'm reader 5, cnt = 6
    I'm reader 3, cnt = 6
    I'm reader 4, cnt = 6
    I'm reader 6, cnt = 6
    I'm reader 7, cnt = 6
    I'm reader 4, cnt = 6
    I'm reader 5, cnt = 6
    I'm reader 3, cnt = 6
    

    在这里插入图片描述