SetCurrentLibrary -- set current library number (V6.0, optional)
void SetCurrentLibrary(int n);
This function is optional and must only be implemented if the HWEXT_LIBRARY_MULTIPLE extension bit has been set. See Extension plugins for details. In that case, Hollywood will call SetCurrentLibrary() to tell your plugin whose library's commands, constants or base table you should return when Hollywood makes the next call to your GetBaseTable(), GetCommands() or GetConstants() functions. The library numbers passed by Hollywood are 0-based, so a value of 0 means the first library. Hollywood will call this function as many times as you've specified in your GetLibraryCount() implementation. See GetLibraryCount for details.

number of the current library (zero-based)

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