Application programming interface functions for supporting an improved message store for hand-held computers

摘要

A set of APIs is used in creating and maintaining hierarchical folder structure for the storage of electronic messages in a hand-held computer. Such a folder structure permits the creation of a folder hierarchy for each message service with which the user has an account. As a result, the hand-held message store can organize messages received from different services. The APIs provide the functions necessary for an application process to access messages in the hierarchical folder structure. This set of APIs also provides backwards compatibility with APIs utilized to create and maintain a flat folder structure organization of the message store. This backward compatibility permits a hand-held computer embodying the present invention to be used to execute application processes that were developed to interact with an earlier generation flat folder structure.