Write a standard lock plus "double check" to create a critical section around a variable access.

写一个标准的lock，在访问变量的前后创建临界区，要有“双重检查”。

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To ensure that you receive valid data, and don't write bad information to the XML, you access the parameters and set the ok variable accordingly.

要确保能够接收到有效的数据，并且避免将错误信息写入XML，我们可以访问其参数并相应地设置ok变量。

youdao

To ensure that you receive valid data, and don't write bad information to the XML, you access the parameters and set the ok variable accordingly.

要确保能够接收到有效的数据，并且避免将错误信息写入XML，我们可以访问其参数并相应地设置ok变量。

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