COM is from Component Object Model and the structured storage(SS) is based on it. Shortly SS is a file system within a file with two kind of objects: storage=>directory and stream=>file and COM defines how to treat that objects in a single file system. Some of the features are: simultaneous access to objects (or part of) from multiple applications, direct or transacted access and so on. In direct access the changes are made immediately, in transacted they are buffered and committed or reverted. There are some functions in OLE32.dll but the question is how to implement the full functionality of SS and call it from LV, may be in another dll...
