SafeArrayUnlock Function
Decrements the lock count of an array so it can be freed or resized.
HRESULT SafeArrayUnlock( SAFEARRAY *psa );
All public static members of the SAFEARRAY data type are thread safe. Instance members are not guaranteed to be thread safe.
For example, consider an application that uses the SafeArrayLock Function and SafeArrayUnlock functions. If these functions are called concurrently from different threads on the same SAFEARRAY data type instance, an inconsistent lock count may be created. This will eventually cause the SafeArrayUnlock function to return E_UNEXPECTED. You can prevent this by providing your own synchronization code.