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When using COM, I typically rely on ATL smart pointers, like ATL::CComPtr and ATL::CComBSTR , for resource management. But some of the methods I'm calling use output parameters to return pointers to allocated storage that I have to free. For example: WCHAR *pszName = nullptr; if (SUCCEEDED(pShellItem->GetDisplayName(SIGDN_FILESYSPATH, &pszName))) { DoSomething(pszName); CoTaskMemFree(pszName); } Note that GetDisplayName allocates memory for the string and returns a pointer to it through the output parameter. It's the caller's responsibility to free that memory with CoTaskMemFree . If DoSomething throws an exception, then the above code will leak. I'd like to use some sort of smart pointer for pszName to avoid such leaks, but the API takes WCHAR** , so I don't see how I can pass anything but the address of a dumb pointer. Since I'm not the one allocating, I can't use RAII. I can use RRID if I can make a deleter like this: struct CoTaskMemDeleter { void operator()(void *p) { ::CoTaskMemFree(p); } }; And then immediately assign the returned pointer to a standard smart pointer like this: WCHAR *pszName = nullptr; if (SUCCEEDED(pShellItem->GetDisplayName(SIGDN_FILESYSPATH, &pszName))) { std::unique_ptr<WCHAR, CoTaskMemDeleter> guard(pszName); DoSomething(pszName); } That works, but it seems error-prone to introduce an extra guard variable. For example, this approach leaves pszName pointing at the released memory, so it would be easy to accidentally use it again. Is there a cleaner way to use a smart pointer or an RAII wrapper for COM-server allocated memory returned by output parameter? Am I missing some

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