37 lines
740 B
Markdown
37 lines
740 B
Markdown
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# ReadWriteLock::ReadLock
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```cpp
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void ReadLock()
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```
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获取读锁。如果有写者持有锁或正在等待写锁，当前线程将阻塞，直到所有写者完成。
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**参数：** 无
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**返回：** 无
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**复杂度：** 平均 O(1)
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**注意：**
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- 多个读者可以同时持有读锁。
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- 写锁具有优先权——正在等待的写者会阻塞新的读者，防止写者饥饿。
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- 读锁不可重入，同一线程不可嵌套持有读锁（会导致死锁）。
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**示例：**
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```cpp
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ReadWriteLock rwLock;
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int sharedValue = 0;
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int ReadValue() {
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rwLock.ReadLock();
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int value = sharedValue;
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rwLock.ReadUnlock();
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return value;
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}
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```
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## 相关文档
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- [ReadWriteLock 总览](readwritelock.md) - 返回类总览
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