[6.1 什么是线程安全](6.1%E4%BB%80%E4%B9%88%E6%98%AF%E7%BA%BF%E7%A8%8B%E5%AE%89%E5%85%A8.md) [6.2 线程安全资源管理器](6.2%E7%BA%BF%E7%A8%8B%E5%AE%89%E5%85%A8%E8%B5%84%E6%BA%90%E7%AE%A1%E7%90%86%E5%99%A8.md)