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copied!<p>Your update is no better. If you want to do this in an RAII style then you need to work a bit harder. The key is that you need to separate the critical section object which is statically allocated, and the lock which is local to all blocks that need protection.</p> <p>The following is lifted from <a href="http://jrdodds.blogs.com/blog/2004/08/raii_in_c.html" rel="noreferrer">Jonathan Dodds</a> but it is a classic pattern.</p> <pre><code>class CriticalSection { public: CriticalSection() { ::InitializeCriticalSection(&m_rep); } ~CriticalSection() { ::DeleteCriticalSection(&m_rep); } void Enter() { ::EnterCriticalSection(&m_rep); } void Leave() { ::LeaveCriticalSection(&m_rep); } private: // copy ops are private to prevent copying CriticalSection(const CriticalSection&); CriticalSection& operator=(const CriticalSection&); CRITICAL_SECTION m_rep; }; </code></pre> <p>Whilst you could do this with inheritance of CRITICAL_SECTION, I feel encapsulation is more appropriate. </p> <p>Next the lock is defined:</p> <pre><code>class CSLock { public: CSLock(CriticalSection& a_section) : m_section(a_section) { m_section.Enter(); } ~CSLock() { m_section.Leave(); } private: // copy ops are private to prevent copying CSLock(const CSLock&); CSLock& operator=(const CSLock&); CriticalSection& m_section; }; </code></pre> <p>Finally, an example of usage:</p> <pre><code>class Example { public: bool Process( … ); … private: CriticalSection m_criticalsection; … }; bool Example::Process( … ) { CSLock lock(m_critsection); // do some stuff … } </code></pre> <p>The point is that there is a single instance of the critical section, shared across all threads. This is what makes a critical section work.</p> <p>In counterpoint, there may be many instances of <code>CSLock</code>, all taken on the same critical section, in simultaneous existence. This allows the <code>Process()</code> method to be called by many threads, but have its code is serialized over the lifetime of the <code>CSLock</code> instance taken on the single shared critical section.</p>

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